A type of scanning probe microscopy in which a probe systematically rides across the surface of a sample being scanned in a raster pattern. The vertical position is recorded as a spring attached to the probe rises and falls in response to peaks and valleys on the surface. These deflections produce a topographic map of the sample.
The use of instrumentation and techniques for visualizing material and details that cannot be seen by the unaided eye. It is usually done by enlarging images, transmitted by light or electron beams, with optical or magnetic lenses that magnify the entire image field. With scanning microscopy, images are generated by collecting output from the specimen in a point-by-point fashion, on a magnified scale, as it is scanned by a narrow beam of light or electrons, a laser, a conductive probe, or a topographical probe.
Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.
Microscopy in which the object is examined directly by an electron beam scanning the specimen point-by-point. The image is constructed by detecting the products of specimen interactions that are projected above the plane of the sample, such as backscattered electrons. Although SCANNING TRANSMISSION ELECTRON MICROSCOPY also scans the specimen point by point with the electron beam, the image is constructed by detecting the electrons, or their interaction products that are transmitted through the sample plane, so that is a form of TRANSMISSION ELECTRON MICROSCOPY.
Any of the numerous types of clay which contain varying proportions of Al2O3 and SiO2. They are made synthetically by heating aluminum fluoride at 1000-2000 degrees C with silica and water vapor. (From Hawley's Condensed Chemical Dictionary, 11th ed)
A light microscopic technique in which only a small spot is illuminated and observed at a time. An image is constructed through point-by-point scanning of the field in this manner. Light sources may be conventional or laser, and fluorescence or transmitted observations are possible.
Microscopy of specimens stained with fluorescent dye (usually fluorescein isothiocyanate) or of naturally fluorescent materials, which emit light when exposed to ultraviolet or blue light. Immunofluorescence microscopy utilizes antibodies that are labeled with fluorescent dye.
A type of scanning probe microscopy in which a very sharp conducting needle is swept just a few angstroms above the surface of a sample. The tiny tunneling current that flows between the sample and the needle tip is measured, and from this are produced three-dimensional topographs. Due to the poor electron conductivity of most biological samples, thin metal coatings are deposited on the sample.
Characteristics or attributes of the outer boundaries of objects, including molecules.
Electron microscopy in which the ELECTRONS or their reaction products that pass down through the specimen are imaged below the plane of the specimen.
Resistance and recovery from distortion of shape.
The development and use of techniques to study physical phenomena and construct structures in the nanoscale size range or smaller.
The properties, processes, and behavior of biological systems under the action of mechanical forces.
Materials which have structured components with at least one dimension in the range of 1 to 100 nanometers. These include NANOCOMPOSITES; NANOPARTICLES; NANOTUBES; and NANOWIRES.
The study of PHYSICAL PHENOMENA and PHYSICAL PROCESSES as applied to living things.
Numerical expression indicating the measure of stiffness in a material. It is defined by the ratio of stress in a unit area of substance to the resulting deformation (strain). This allows the behavior of a material under load (such as bone) to be calculated.
Microscopy in which the samples are first stained immunocytochemically and then examined using an electron microscope. Immunoelectron microscopy is used extensively in diagnostic virology as part of very sensitive immunoassays.
Layers of lipid molecules which are two molecules thick. Bilayer systems are frequently studied as models of biological membranes.
The performance of dissections, injections, surgery, etc., by the use of micromanipulators (attachments to a microscope) that manipulate tiny instruments.
The behaviors of materials under force.
The physical characteristics and processes of biological systems.
Electron microscopy involving rapid freezing of the samples. The imaging of frozen-hydrated molecules and organelles permits the best possible resolution closest to the living state, free of chemical fixatives or stains.
Scanning microscopy in which a very sharp probe is employed in close proximity to a surface, exploiting a particular surface-related property. When this property is local topography, the method is atomic force microscopy (MICROSCOPY, ATOMIC FORCE), and when it is local conductivity, the method is scanning tunneling microscopy (MICROSCOPY, SCANNING TUNNELING).
Functionally and structurally differentiated, purple-pigmented regions of the cytoplasmic membrane of some strains of Halobacterium halobium. The membrane develops under anaerobic conditions and is made almost entirely of the purple pigment BACTERIORHODOPSINS. (From Singleton & Sainsbury Dictionary of Microbiology and Molecular Biology, 2d ed)
The force applied by the masticatory muscles in dental occlusion.
Fluorescence microscopy utilizing multiple low-energy photons to produce the excitation event of the fluorophore. Multiphoton microscopes have a simplified optical path in the emission side due to the lack of an emission pinhole, which is necessary with normal confocal microscopes. Ultimately this allows spatial isolation of the excitation event, enabling deeper imaging into optically thick tissue, while restricting photobleaching and phototoxicity to the area being imaged.
The adhesion of gases, liquids, or dissolved solids onto a surface. It includes adsorptive phenomena of bacteria and viruses onto surfaces as well. ABSORPTION into the substance may follow but not necessarily.
A type of TRANSMISSION ELECTRON MICROSCOPY in which the object is examined directly by an extremely narrow electron beam scanning the specimen point-by-point and using the reactions of the electrons that are transmitted through the specimen to create the image. It should not be confused with SCANNING ELECTRON MICROSCOPY.
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
Microscopy in which television cameras are used to brighten magnified images that are otherwise too dark to be seen with the naked eye. It is used frequently in TELEPATHOLOGY.
Relating to the size of solids.
The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.
A giant elastic protein of molecular mass ranging from 2,993 kDa (cardiac), 3,300 kDa (psoas), to 3,700 kDa (soleus) having a kinase domain. The amino- terminal is involved in a Z line binding, and the carboxy-terminal region is bound to the myosin filament with an overlap between the counter-connectin filaments at the M line.
The study of the energy of electrons ejected from matter by the photoelectric effect, i.e., as a direct result of absorption of energy from electromagnetic radiation. As the energies of the electrons are characteristic of a specific element, the measurement of the energy of these electrons is a technique used to determine the chemical composition of surfaces.
Synthetic phospholipid used in liposomes and lipid bilayers to study biological membranes. It is also a major constituent of PULMONARY SURFACTANTS.
The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.
A purely physical condition which exists within any material because of strain or deformation by external forces or by non-uniform thermal expansion; expressed quantitatively in units of force per unit area.
The characteristic three-dimensional shape of a molecule.
Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.
The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).
The science and application of a double-beam transmission interference microscope in which the illuminating light beam is split into two paths. One beam passes through the specimen while the other beam reflects off a reference mirror before joining and interfering with the other. The observed optical path difference between the two beams can be measured and used to discriminate minute differences in thickness and refraction of non-stained transparent specimens, such as living cells in culture.
A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).
The resistance that a gaseous or liquid system offers to flow when it is subjected to shear stress. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
A form of interference microscopy in which variations of the refracting index in the object are converted into variations of intensity in the image. This is achieved by the action of a phase plate.
A property of the surface of an object that makes it stick to another surface.
Compounds formed by the joining of smaller, usually repeating, units linked by covalent bonds. These compounds often form large macromolecules (e.g., BIOPOLYMERS; PLASTICS).
The motion of phospholipid molecules within the lipid bilayer, dependent on the classes of phospholipids present, their fatty acid composition and degree of unsaturation of the acyl chains, the cholesterol concentration, and temperature.
A yellow metallic element with the atomic symbol Au, atomic number 79, and atomic weight 197. It is used in jewelry, goldplating of other metals, as currency, and in dental restoration. Many of its clinical applications, such as ANTIRHEUMATIC AGENTS, are in the form of its salts.
Microscopy using polarized light in which phenomena due to the preferential orientation of optical properties with respect to the vibration plane of the polarized light are made visible and correlated parameters are made measurable.
Artificially produced membranes, such as semipermeable membranes used in artificial kidney dialysis (RENAL DIALYSIS), monomolecular and bimolecular membranes used as models to simulate biological CELL MEMBRANES. These membranes are also used in the process of GUIDED TISSUE REGENERATION.
The assembly of the QUATERNARY PROTEIN STRUCTURE of multimeric proteins (MULTIPROTEIN COMPLEXES) from their composite PROTEIN SUBUNITS.
The branch of physics which deals with the motions of material bodies, including kinematics, dynamics, and statics. When the laws of mechanics are applied to living structures, as to the locomotor system, it is referred to as BIOMECHANICAL PHENOMENA. (From Dorland, 28th ed)
Elements of limited time intervals, contributing to particular results or situations.
The testing of materials and devices, especially those used for PROSTHESES AND IMPLANTS; SUTURES; TISSUE ADHESIVES; etc., for hardness, strength, durability, safety, efficacy, and biocompatibility.
An allotropic form of carbon that is used in pencils, as a lubricant, and in matches and explosives. It is obtained by mining and its dust can cause lung irritation.
Agents that emit light after excitation by light. The wave length of the emitted light is usually longer than that of the incident light. Fluorochromes are substances that cause fluorescence in other substances, i.e., dyes used to mark or label other compounds with fluorescent tags.
A fibrous protein complex that consists of proteins folded into a specific cross beta-pleated sheet structure. This fibrillar structure has been found as an alternative folding pattern for a variety of functional proteins. Deposits of amyloid in the form of AMYLOID PLAQUES are associated with a variety of degenerative diseases. The amyloid structure has also been found in a number of functional proteins that are unrelated to disease.
Computer-based representation of physical systems and phenomena such as chemical processes.
Hard, amorphous, brittle, inorganic, usually transparent, polymerous silicate of basic oxides, usually potassium or sodium. It is used in the form of hard sheets, vessels, tubing, fibers, ceramics, beads, etc.
Filamentous proteins that are the main constituent of the thin filaments of muscle fibers. The filaments (known also as filamentous or F-actin) can be dissociated into their globular subunits; each subunit is composed of a single polypeptide 375 amino acids long. This is known as globular or G-actin. In conjunction with MYOSINS, actin is responsible for the contraction and relaxation of muscle.
The homogeneous mixtures formed by the mixing of a solid, liquid, or gaseous substance (solute) with a liquid (the solvent), from which the dissolved substances can be recovered by physical processes. (From Grant & Hackh's Chemical Dictionary, 5th ed)
Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.
A technique that uses LASERS to trap, image, and manipulate small objects (biomolecules, supramolecular assembles, DENDRIMERS) in three dimensional space. (From Glossary of Biotechnology and Nanobiotechnology Terms, 4th ed.)
A technique of inputting two-dimensional images into a computer and then enhancing or analyzing the imagery into a form that is more useful to the human observer.
Adherence of cells to surfaces or to other cells.
The network of filaments, tubules, and interconnecting filamentous bridges which give shape, structure, and organization to the cytoplasm.
The formation of crystalline substances from solutions or melts. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Nanometer-sized particles that are nanoscale in three dimensions. They include nanocrystaline materials; NANOCAPSULES; METAL NANOPARTICLES; DENDRIMERS, and QUANTUM DOTS. The uses of nanoparticles include DRUG DELIVERY SYSTEMS and cancer targeting and imaging.
The spatial arrangement of the atoms of a nucleic acid or polynucleotide that results in its characteristic 3-dimensional shape.
The properties and processes of materials that affect their behavior under force.
The process by which cells convert mechanical stimuli into a chemical response. It can occur in both cells specialized for sensing mechanical cues such as MECHANORECEPTORS, and in parenchymal cells whose primary function is not mechanosensory.
A peptide which is a homopolymer of lysine.
A process leading to shortening and/or development of tension in muscle tissue. Muscle contraction occurs by a sliding filament mechanism whereby actin filaments slide inward among the myosin filaments.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
A trace element that constitutes about 27.6% of the earth's crust in the form of SILICON DIOXIDE. It does not occur free in nature. Silicon has the atomic symbol Si, atomic number 14, and atomic weight [28.084; 28.086].
Conformational transitions of the shape of a protein to various unfolded states.
The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.
Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.
A test to determine the relative hardness of a metal, mineral, or other material according to one of several scales, such as Brinell, Mohs, Rockwell, Vickers, or Shore. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
A 60-kDa extracellular protein of Streptomyces avidinii with four high-affinity biotin binding sites. Unlike AVIDIN, streptavidin has a near neutral isoelectric point and is free of carbohydrate side chains.
The measurement of the amplitude of the components of a complex waveform throughout the frequency range of the waveform. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
The rate dynamics in chemical or physical systems.
The mechanical property of material that determines its resistance to force. HARDNESS TESTS measure this property.
A change of a substance from one form or state to another.
A clear, odorless, tasteless liquid that is essential for most animal and plant life and is an excellent solvent for many substances. The chemical formula is hydrogen oxide (H2O). (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
A spectroscopic technique in which a range of wavelengths is presented simultaneously with an interferometer and the spectrum is mathematically derived from the pattern thus obtained.
Detergent-insoluble CELL MEMBRANE components. They are enriched in SPHINGOLIPIDS and CHOLESTEROL and clustered with glycosyl-phosphatidylinositol (GPI)-anchored proteins.
The level of protein structure in which regular hydrogen-bond interactions within contiguous stretches of polypeptide chain give rise to alpha helices, beta strands (which align to form beta sheets) or other types of coils. This is the first folding level of protein conformation.
The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
The accumulation of an electric charge on a object
Surface resistance to the relative motion of one body against the rubbing, sliding, rolling, or flowing of another with which it is in contact.
The characteristic 3-dimensional shape and arrangement of multimeric proteins (aggregates of more than one polypeptide chain).
Established cell cultures that have the potential to propagate indefinitely.
A rigorously mathematical analysis of energy relationships (heat, work, temperature, and equilibrium). It describes systems whose states are determined by thermal parameters, such as temperature, in addition to mechanical and electromagnetic parameters. (From Hawley's Condensed Chemical Dictionary, 12th ed)
Proteins found in any species of bacterium.
The maximum stress a material subjected to a stretching load can withstand without tearing. (McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed, p2001)
Polymerized forms of styrene used as a biocompatible material, especially in dentistry. They are thermoplastic and are used as insulators, for injection molding and casting, as sheets, plates, rods, rigid forms and beads.
A generic term for all substances having the properties of stretching under tension, high tensile strength, retracting rapidly, and recovering their original dimensions fully. They are generally POLYMERS.
Fibers composed of MICROFILAMENT PROTEINS, which are predominately ACTIN. They are the smallest of the cytoskeletal filaments.
The diversion of RADIATION (thermal, electromagnetic, or nuclear) from its original path as a result of interactions or collisions with atoms, molecules, or larger particles in the atmosphere or other media. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Derivatives of phosphatidic acids in which the phosphoric acid is bound in ester linkage to a choline moiety. Complete hydrolysis yields 1 mole of glycerol, phosphoric acid and choline and 2 moles of fatty acids.
A subtype of striated muscle, attached by TENDONS to the SKELETON. Skeletal muscles are innervated and their movement can be consciously controlled. They are also called voluntary muscles.
Methods of creating machines and devices.
The mixture of gases present in the earth's atmosphere consisting of oxygen, nitrogen, carbon dioxide, and small amounts of other gases.
Processes involved in the formation of TERTIARY PROTEIN STRUCTURE.
Physical motion, i.e., a change in position of a body or subject as a result of an external force. It is distinguished from MOVEMENT, a process resulting from biological activity.
Any of a variety of procedures which use biomolecular probes to measure the presence or concentration of biological molecules, biological structures, microorganisms, etc., by translating a biochemical interaction at the probe surface into a quantifiable physical signal.
Linear POLYPEPTIDES that are synthesized on RIBOSOMES and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of AMINO ACIDS determines the shape the polypeptide will take, during PROTEIN FOLDING, and the function of the protein.
One of the protein CROSS-LINKING REAGENTS that is used as a disinfectant for sterilization of heat-sensitive equipment and as a laboratory reagent, especially as a fixative.
Colloids with a solid continuous phase and liquid as the dispersed phase; gels may be unstable when, due to temperature or other cause, the solid phase liquefies; the resulting colloid is called a sol.
The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
The marking of biological material with a dye or other reagent for the purpose of identifying and quantitating components of tissues, cells or their extracts.
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
Proteins that are chemically bound to a substrate material which renders their location fixed. The immobilization of proteins allows their use in chemical reactions without being diluted by solvent.
The fundamental, structural, and functional units or subunits of living organisms. They are composed of CYTOPLASM containing various ORGANELLES and a CELL MEMBRANE boundary.
Physicochemical property of fimbriated (FIMBRIAE, BACTERIAL) and non-fimbriated bacteria of attaching to cells, tissue, and nonbiological surfaces. It is a factor in bacterial colonization and pathogenicity.
The process of generating three-dimensional images by electronic, photographic, or other methods. For example, three-dimensional images can be generated by assembling multiple tomographic images with the aid of a computer, while photographic 3-D images (HOLOGRAPHY) can be made by exposing film to the interference pattern created when two laser light sources shine on an object.
The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.
A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.
A family of structurally related collagens that form the characteristic collagen fibril bundles seen in CONNECTIVE TISSUE.
Compounds and molecular complexes that consist of very large numbers of atoms and are generally over 500 kDa in size. In biological systems macromolecular substances usually can be visualized using ELECTRON MICROSCOPY and are distinguished from ORGANELLES by the lack of a membrane structure.
A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
An optical source that emits photons in a coherent beam. Light Amplification by Stimulated Emission of Radiation (LASER) is brought about using devices that transform light of varying frequencies into a single intense, nearly nondivergent beam of monochromatic radiation. Lasers operate in the infrared, visible, ultraviolet, or X-ray regions of the spectrum.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
A dark-gray, metallic element of widespread distribution but occurring in small amounts; atomic number, 22; atomic weight, 47.90; symbol, Ti; specific gravity, 4.5; used for fixation of fractures. (Dorland, 28th ed)
The study of the deformation and flow of matter, usually liquids or fluids, and of the plastic flow of solids. The concept covers consistency, dilatancy, liquefaction, resistance to flow, shearing, thixotrophy, and VISCOSITY.
The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.
Inorganic compounds that contain silicon as an integral part of the molecule.
Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.
Spherical particles of nanometer dimensions.
A computer simulation developed to study the motion of molecules over a period of time.
Protein analogs and derivatives of the Aequorea victoria green fluorescent protein that emit light (FLUORESCENCE) when excited with ULTRAVIOLET RAYS. They are used in REPORTER GENES in doing GENETIC TECHNIQUES. Numerous mutants have been made to emit other colors or be sensitive to pH.
The quality or state of being wettable or the degree to which something can be wet. This is also the ability of any solid surface to be wetted when in contact with a liquid whose surface tension is reduced so that the liquid spreads over the surface of the solid.
The thermodynamic interaction between a substance and WATER.
Synthetic or natural materials, other than DRUGS, that are used to replace or repair any body TISSUES or bodily function.
A genus of gram-negative bacteria widely distributed in fresh water as well as marine and hypersaline habitats.
Artificial, single or multilaminar vesicles (made from lecithins or other lipids) that are used for the delivery of a variety of biological molecules or molecular complexes to cells, for example, drug delivery and gene transfer. They are also used to study membranes and membrane proteins.
A chemical system that functions to control the levels of specific ions in solution. When the level of hydrogen ion in solution is controlled the system is called a pH buffer.
The quantity of volume or surface area of CELLS.
The study of MAGNETIC PHENOMENA.
Materials fabricated by BIOMIMETICS techniques, i.e., based on natural processes found in biological systems.
A meshwork-like substance found within the extracellular space and in association with the basement membrane of the cell surface. It promotes cellular proliferation and provides a supporting structure to which cells or cell lysates in culture dishes adhere.
A scientific tool based on ULTRASONOGRAPHY and used not only for the observation of microstructure in metalwork but also in living tissue. In biomedical application, the acoustic propagation speed in normal and abnormal tissues can be quantified to distinguish their tissue elasticity and other properties.
Disruption of the non-covalent bonds and/or disulfide bonds responsible for maintaining the three-dimensional shape and activity of the native protein.
Lipids containing one or more phosphate groups, particularly those derived from either glycerol (phosphoglycerides see GLYCEROPHOSPHOLIPIDS) or sphingosine (SPHINGOLIPIDS). They are polar lipids that are of great importance for the structure and function of cell membranes and are the most abundant of membrane lipids, although not stored in large amounts in the system.
Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.
The quality of surface form or outline of CELLS.
Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.
Small uniformly-sized spherical particles, of micrometer dimensions, frequently labeled with radioisotopes or various reagents acting as tags or markers.
The branch of science that deals with the geometric description of crystals and their internal arrangement. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Determination, by measurement or comparison with a standard, of the correct value of each scale reading on a meter or other measuring instrument; or determination of the settings of a control device that correspond to particular values of voltage, current, frequency or other output.
Coating with a metal or alloy by electrolysis.
Manufacturing technology for making microscopic devices in the micrometer range (typically 1-100 micrometers), such as integrated circuits or MEMS. The process usually involves replication and parallel fabrication of hundreds or millions of identical structures using various thin film deposition techniques and carried out in environmentally-controlled clean rooms.
The part of a cell that contains the CYTOSOL and small structures excluding the CELL NUCLEUS; MITOCHONDRIA; and large VACUOLES. (Glick, Glossary of Biochemistry and Molecular Biology, 1990)
A change from planar to elliptic polarization when an initially plane-polarized light wave traverses an optically active medium. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Force exerted when gripping or grasping.
The parts of a macromolecule that directly participate in its specific combination with another molecule.
The process by which two molecules of the same chemical composition form a condensation product or polymer.
The use of molecularly targeted imaging probes to localize and/or monitor biochemical and cellular processes via various imaging modalities that include RADIONUCLIDE IMAGING; ULTRASONOGRAPHY; MAGNETIC RESONANCE IMAGING; FLUORESCENCE IMAGING; and MICROSCOPY.
Slender, cylindrical filaments found in the cytoskeleton of plant and animal cells. They are composed of the protein TUBULIN and are influenced by TUBULIN MODULATORS.
The technique of spraying a tissue specimen with a thin coat of a heavy metal such as platinum. The specimen is sprayed from an oblique angle, which results in the uneven deposition of the coating. The varying thicknesses create a shadow effect and give a three-dimensional appearance to the specimen.

Ligand substitution of receptor targeted DNA complexes affects gene transfer into hepatoma cells. (1/3462)

We have targeted the serpin enzyme complex receptor for gene transfer in human hepatoma cell lines using peptides < 30 amino acids in length which contain the five amino acid recognition sequence for this receptor, coupled to poly K of average chain length 100 K, using the heterobifunctional coupling reagent sulfo-LC SPDP. The number of sulfo-LC SPDP modified poly-L-lysine residues, as well as the degree of peptide substitution was assessed by nuclear magnetic resonance spectroscopy. Conjugates were prepared in which 3.5%, 7.8% or 26% of the lysine residues contained the sulfo-LC SPDP moiety. Each of these conjugates was then coupled with ligand peptides so that one in 370, one in 1039, or one in 5882 lysines were substituted with receptor ligand. Electron microscopy and atomic force microscopy were used to assess complex structure and size. HuH7 human hepatoma cells were transfected with complexes of these conjugates with the plasmid pGL3 and luciferase expression measured 2 to 16 days after treatment. All the protein conjugates in which 26% of the K residues were modified with sulfo-LC SPDP were poor gene transfer reagents. Complexes containing less substituted poly K, averaged 17 +/- 0.5 nm in diameter and gave peak transgene expression of 3-4 x 10(6) ILU/mg which persisted (> 7 x 10(5) ILU) at 16 days. Of these, more substituted polymers condensed DNA into complexes averaging 20 +/- 0.7 nm in diameter and gave five-fold less luciferase than complexes containing less substituted conjugates. As few as eight to 11 ligands per complex are optimal for DNA delivery via the SEC receptor. The extent of substitution of receptor-mediated gene transfer complexes affects the size of the complexes, as well as the intensity and duration of transgene expression. These observations may permit tailoring of complex construction for the usage required.  (+info)

Electrically excitable normal rat kidney fibroblasts: A new model system for cell-semiconductor hybrids. (2/3462)

In testing various designs of cell-semiconductor hybrids, the choice of a suitable type of electrically excitable cell is crucial. Here normal rat kidney (NRK) fibroblasts are presented as a cell line, easily maintained in culture, that may substitute for heart or nerve cells in many experiments. Like heart muscle cells, NRK fibroblasts form electrically coupled confluent cell layers, in which propagating action potentials are spontaneously generated. These, however, are not associated with mechanical disturbances. Here we compare heart muscle cells and NRK fibroblasts with respect to action potential waveform, morphology, and substrate adhesion profile, using the whole-cell variant of the patch-clamp technique, atomic force microscopy (AFM), and reflection interference contrast microscopy (RICM), respectively. Our results clearly demonstrate that NRK fibroblasts should provide a highly suitable test system for investigating the signal transfer between electrically excitable cells and extracellular detectors, available at a minimum cost and effort for the experimenters.  (+info)

The vacuolating toxin from Helicobacter pylori forms hexameric pores in lipid bilayers at low pH. (3/3462)

Pathogenic strains of Helicobacter pylori secrete a cytotoxin, VacA, that in the presence of weak bases, causes osmotic swelling of acidic intracellular compartments enriched in markers for late endosomes and lysosomes. The molecular mechanisms by which VacA causes this vacuolation remain largely unknown. At neutral pH, VacA is predominantly a water-soluble dodecamer formed by two apposing hexamers. In this report, we show by using atomic force microscopy that below pH approximately 5, VacA associates with anionic lipid bilayers to form hexameric membrane-associated complexes. We propose that water-soluble dodecameric VacA proteins disassemble at low pH and reassemble into membrane-spanning hexamers. The surface contour of the membrane-bound hexamer is strikingly similar to the outer surface of the soluble dodecamer, suggesting that the VacA surface in contact with the membrane is buried within the dodecamer before protonation. In addition, electrophysiological measurements indicate that, under the conditions determined by atomic force microscopy for membrane association, VacA forms pores across planar lipid bilayers. This low pH-triggered pore formation is likely a critical step in VacA activity.  (+info)

Atomic force microscopy: a forceful way with single molecules. (4/3462)

The atomic force microscope (AFM) now routinely provides images that reveal subnanometer surface structures of biomolecules. The sensitivity and precision of AFM provide new opportunities for studying the mechanical properties of biomolecules and their interactions in their native environment.  (+info)

In situ atomic force microscopy study of Alzheimer's beta-amyloid peptide on different substrates: new insights into mechanism of beta-sheet formation. (5/3462)

We have applied in situ atomic force microscopy to directly observe the aggregation of Alzheimer's beta-amyloid peptide (Abeta) in contact with two model solid surfaces: hydrophilic mica and hydrophobic graphite. The time course of aggregation was followed by continuous imaging of surfaces remaining in contact with 10-500 microM solutions of Abeta in PBS (pH 7.4). Visualization of fragile nanoscale aggregates of Abeta was made possible by the application of a tapping mode of imaging, which minimizes the lateral forces between the probe tip and the sample. The size and the shape of Abeta aggregates, as well as the kinetics of their formation, exhibited pronounced dependence on the physicochemical nature of the surface. On hydrophilic mica, Abeta formed particulate, pseudomicellar aggregates, which at higher Abeta concentration had the tendency to form linear assemblies, reminiscent of protofibrillar species described recently in the literature. In contrast, on hydrophobic graphite Abeta formed uniform, elongated sheets. The dimensions of those sheets were consistent with the dimensions of beta-sheets with extended peptide chains perpendicular to the long axis of the aggregate. The sheets of Abeta were oriented along three directions at 120 degrees to each other, resembling the crystallographic symmetry of a graphite surface. Such substrate-templated self-assembly may be the distinguishing feature of beta-sheets in comparison with alpha-helices. These studies show that in situ atomic force microscopy enables direct assessment of amyloid aggregation in physiological fluids and suggest that Abeta fibril formation may be driven by interactions at the interface of aqueous solutions and hydrophobic substrates, as occurs in membranes and lipoprotein particles in vivo.  (+info)

Mechanical and chemical unfolding of a single protein: a comparison. (6/3462)

Is the mechanical unraveling of protein domains by atomic force microscopy (AFM) just a technological feat or a true measurement of their unfolding? By engineering a protein made of tandem repeats of identical Ig modules, we were able to get explicit AFM data on the unfolding rate of a single protein domain that can be accurately extrapolated to zero force. We compare this with chemical unfolding rates for untethered modules extrapolated to 0 M denaturant. The unfolding rates obtained by the two methods are the same. Furthermore, the transition state for unfolding appears at the same position on the folding pathway when assessed by either method. These results indicate that mechanical unfolding of a single protein by AFM does indeed reflect the same event that is observed in traditional unfolding experiments. The way is now open for the extensive use of AFM to measure folding reactions at the single-molecule level. Single-molecule AFM recordings have the added advantage that they define the reaction coordinate and expose rare unfolding events that cannot be observed in the absence of chemical denaturants.  (+info)

Probing the Saccharomyces cerevisiae centromeric DNA (CEN DNA)-binding factor 3 (CBF3) kinetochore complex by using atomic force microscopy. (7/3462)

Yeast centromeric DNA (CEN DNA) binding factor 3 (CBF3) is a multisubunit protein complex that binds to the essential CDEIII element in CEN DNA. The four CBF3 proteins are required for accurate chromosome segregation and are considered to be core components of the yeast kinetochore. We have examined the structure of the CBF3-CEN DNA complex by atomic force microscopy. Assembly of CBF3-CEN DNA complexes was performed by combining purified CBF3 proteins with a DNA fragment that includes the CEN region from yeast chromosome III. Atomic force microscopy images showed DNA molecules with attached globular bodies. The contour length of the DNA containing the complex is approximately 9% shorter than the DNA alone, suggesting some winding of DNA within the complex. The measured location of the single binding site indicates that the complex is located asymmetrically to the right of CDEIII extending away from CDEI and CDEII, which is consistent with previous data. The CEN DNA is bent approximately 55 degrees at the site of complex formation. A significant fraction of the complexes are linked in pairs, showing three to four DNA arms, with molecular volumes approximately three times the mean volumes of two-armed complexes. These multi-armed complexes indicate that CBF3 can bind two DNA molecules together in vitro and, thus, may be involved in holding together chromatid pairs during mitosis.  (+info)

Ethanol-induced structural transitions of DNA on mica. (8/3462)

The effect of ethanol on the structure of DNA confined to mica in the presence of Mg2+was examined by varying the ethanol concentration and imaging the DNA by atomic force microscopy. Contour length measurements of the DNA show a transition from all-B-form at 0% ethanol to all-A-form at >25% ethanol. At intermediate ethanol concentrations, contour lengths suggest that individual molecules of air-dried DNA are trapped with mixed compositions of A-form and B-form. The relative composition depends on the ethanol concentration. Fitting the length distributions at intermediate ethanol concentrations to a simple binomial model results in an upper bound estimate for the A-form and B-form domains of approximately 54 bp in the individual molecules. In addition to length changes, the apparent persistence length of DNA decreases with increasing ethanol concentration. At high concentrations of ethanol (>20%), DNA formed several higher order structures, including flower shaped condensates and toroids.  (+info)

Atomic Force Microscopy (AFM) is a type of microscopy that allows visualization and measurement of surfaces at the atomic level. It works by using a sharp probe, called a tip, that is mounted on a flexible cantilever. The tip is brought very close to the surface of the sample and as the sample is scanned, the forces between the tip and the sample cause the cantilever to deflect. This deflection is measured and used to generate a topographic map of the surface with extremely high resolution, often on the order of fractions of a nanometer. AFM can be used to study both conductive and non-conductive samples, and can operate in various environments, including air and liquid. It has applications in fields such as materials science, biology, and chemistry.

Microscopy is a technical field in medicine that involves the use of microscopes to observe structures and phenomena that are too small to be seen by the naked eye. It allows for the examination of samples such as tissues, cells, and microorganisms at high magnifications, enabling the detection and analysis of various medical conditions, including infections, diseases, and cellular abnormalities.

There are several types of microscopy used in medicine, including:

1. Light Microscopy: This is the most common type of microscopy, which uses visible light to illuminate and magnify samples. It can be used to examine a wide range of biological specimens, such as tissue sections, blood smears, and bacteria.
2. Electron Microscopy: This type of microscopy uses a beam of electrons instead of light to produce highly detailed images of samples. It is often used in research settings to study the ultrastructure of cells and tissues.
3. Fluorescence Microscopy: This technique involves labeling specific molecules within a sample with fluorescent dyes, allowing for their visualization under a microscope. It can be used to study protein interactions, gene expression, and cell signaling pathways.
4. Confocal Microscopy: This type of microscopy uses a laser beam to scan a sample point by point, producing high-resolution images with reduced background noise. It is often used in medical research to study the structure and function of cells and tissues.
5. Scanning Probe Microscopy: This technique involves scanning a sample with a physical probe, allowing for the measurement of topography, mechanical properties, and other characteristics at the nanoscale. It can be used in medical research to study the structure and function of individual molecules and cells.

Electron microscopy (EM) is a type of microscopy that uses a beam of electrons to create an image of the sample being examined, resulting in much higher magnification and resolution than light microscopy. There are several types of electron microscopy, including transmission electron microscopy (TEM), scanning electron microscopy (SEM), and reflection electron microscopy (REM).

In TEM, a beam of electrons is transmitted through a thin slice of the sample, and the electrons that pass through the sample are focused to form an image. This technique can provide detailed information about the internal structure of cells, viruses, and other biological specimens, as well as the composition and structure of materials at the atomic level.

In SEM, a beam of electrons is scanned across the surface of the sample, and the electrons that are scattered back from the surface are detected to create an image. This technique can provide information about the topography and composition of surfaces, as well as the structure of materials at the microscopic level.

REM is a variation of SEM in which the beam of electrons is reflected off the surface of the sample, rather than scattered back from it. This technique can provide information about the surface chemistry and composition of materials.

Electron microscopy has a wide range of applications in biology, medicine, and materials science, including the study of cellular structure and function, disease diagnosis, and the development of new materials and technologies.

Scanning electron microscopy (SEM) is a type of electron microscopy that uses a focused beam of electrons to scan the surface of a sample and produce a high-resolution image. In SEM, a beam of electrons is scanned across the surface of a specimen, and secondary electrons are emitted from the sample due to interactions between the electrons and the atoms in the sample. These secondary electrons are then detected by a detector and used to create an image of the sample's surface topography. SEM can provide detailed images of the surface of a wide range of materials, including metals, polymers, ceramics, and biological samples. It is commonly used in materials science, biology, and electronics for the examination and analysis of surfaces at the micro- and nanoscale.

Aluminum silicates are a type of mineral compound that consist of aluminum, silicon, and oxygen in their chemical structure. They are often found in nature and can be categorized into several groups, including kaolinite, illite, montmorillonite, and bentonite. These minerals have various industrial and commercial uses, including as fillers and extenders in products like paper, paint, and rubber. In the medical field, certain types of aluminum silicates (like bentonite) have been used in some medicinal and therapeutic applications, such as detoxification and gastrointestinal disorders. However, it's important to note that the use of these minerals in medical treatments is not widely accepted or supported by extensive scientific evidence.

Confocal microscopy is a powerful imaging technique used in medical and biological research to obtain high-resolution, contrast-rich images of thick samples. This super-resolution technology provides detailed visualization of cellular structures and processes at various depths within a specimen.

In confocal microscopy, a laser beam focused through a pinhole illuminates a small spot within the sample. The emitted fluorescence or reflected light from this spot is then collected by a detector, passing through a second pinhole that ensures only light from the focal plane reaches the detector. This process eliminates out-of-focus light, resulting in sharp images with improved contrast compared to conventional widefield microscopy.

By scanning the laser beam across the sample in a raster pattern and collecting fluorescence at each point, confocal microscopy generates optical sections of the specimen. These sections can be combined to create three-dimensional reconstructions, allowing researchers to study cellular architecture and interactions within complex tissues.

Confocal microscopy has numerous applications in medical research, including studying protein localization, tracking intracellular dynamics, analyzing cell morphology, and investigating disease mechanisms at the cellular level. Additionally, it is widely used in clinical settings for diagnostic purposes, such as analyzing skin lesions or detecting pathogens in patient samples.

Fluorescence microscopy is a type of microscopy that uses fluorescent dyes or proteins to highlight and visualize specific components within a sample. In this technique, the sample is illuminated with high-energy light, typically ultraviolet (UV) or blue light, which excites the fluorescent molecules causing them to emit lower-energy, longer-wavelength light, usually visible light in the form of various colors. This emitted light is then collected by the microscope and detected to produce an image.

Fluorescence microscopy has several advantages over traditional brightfield microscopy, including the ability to visualize specific structures or molecules within a complex sample, increased sensitivity, and the potential for quantitative analysis. It is widely used in various fields of biology and medicine, such as cell biology, neuroscience, and pathology, to study the structure, function, and interactions of cells and proteins.

There are several types of fluorescence microscopy techniques, including widefield fluorescence microscopy, confocal microscopy, two-photon microscopy, and total internal reflection fluorescence (TIRF) microscopy, each with its own strengths and limitations. These techniques can provide valuable insights into the behavior of cells and proteins in health and disease.

Scanning Tunneling Microscopy (STM) is not strictly a medical definition, but it is a type of microscopy used in some areas of scientific research including biophysics and nanotechnology. However, I can provide a general definition:

Scanning Tunneling Microscopy (STM) is a type of microscopy that uses quantum tunneling to form an image of a sample surface at the atomic level. In this process, a sharp conductive tip is brought very close to the surface of the sample, and a voltage bias is applied between the two. Electrons can tunnel through the vacuum gap between the tip and the sample, and the resulting current is measured and used to form an image of the surface topography with atomic resolution. It's worth noting that STM is not commonly used in medical diagnosis or treatment, but it has been used in some research applications related to medicine, such as studying the structure of individual molecules or investigating the properties of biomaterials at the nanoscale.

Surface properties in the context of medical science refer to the characteristics and features of the outermost layer or surface of a biological material or structure, such as cells, tissues, organs, or medical devices. These properties can include physical attributes like roughness, smoothness, hydrophobicity or hydrophilicity, and electrical conductivity, as well as chemical properties like charge, reactivity, and composition.

In the field of biomaterials science, understanding surface properties is crucial for designing medical implants, devices, and drug delivery systems that can interact safely and effectively with biological tissues and fluids. Surface modifications, such as coatings or chemical treatments, can be used to alter surface properties and enhance biocompatibility, improve lubricity, reduce fouling, or promote specific cellular responses like adhesion, proliferation, or differentiation.

Similarly, in the field of cell biology, understanding surface properties is essential for studying cell-cell interactions, cell signaling, and cell behavior. Cells can sense and respond to changes in their environment, including variations in surface properties, which can influence cell shape, motility, and function. Therefore, characterizing and manipulating surface properties can provide valuable insights into the mechanisms of cellular processes and offer new strategies for developing therapies and treatments for various diseases.

Transmission electron microscopy (TEM) is a type of microscopy in which an electron beam is transmitted through a ultra-thin specimen, interacting with it as it passes through. An image is formed from the interaction of the electrons with the specimen; the image is then magnified and visualized on a fluorescent screen or recorded on an electronic detector (or photographic film in older models).

TEM can provide high-resolution, high-magnification images that can reveal the internal structure of specimens including cells, viruses, and even molecules. It is widely used in biological and materials science research to investigate the ultrastructure of cells, tissues and materials. In medicine, TEM is used for diagnostic purposes in fields such as virology and bacteriology.

It's important to note that preparing a sample for TEM is a complex process, requiring specialized techniques to create thin (50-100 nm) specimens. These include cutting ultrathin sections of embedded samples using an ultramicrotome, staining with heavy metal salts, and positive staining or negative staining methods.

In medicine, elasticity refers to the ability of a tissue or organ to return to its original shape after being stretched or deformed. This property is due to the presence of elastic fibers in the extracellular matrix of the tissue, which can stretch and recoil like rubber bands.

Elasticity is an important characteristic of many tissues, particularly those that are subjected to repeated stretching or compression, such as blood vessels, lungs, and skin. For example, the elasticity of the lungs allows them to expand and contract during breathing, while the elasticity of blood vessels helps maintain normal blood pressure by allowing them to expand and constrict in response to changes in blood flow.

In addition to its role in normal physiology, elasticity is also an important factor in the diagnosis and treatment of various medical conditions. For example, decreased elasticity in the lungs can be a sign of lung disease, while increased elasticity in the skin can be a sign of aging or certain genetic disorders. Medical professionals may use techniques such as pulmonary function tests or skin biopsies to assess elasticity and help diagnose these conditions.

Nanotechnology is not a medical term per se, but it is a field of study with potential applications in medicine. According to the National Nanotechnology Initiative, nanotechnology is defined as "the understanding and control of matter at the nanoscale, at dimensions between approximately 1 and 100 nanometers, where unique phenomena enable novel applications."

In the context of medicine, nanotechnology has the potential to revolutionize the way we diagnose, treat, and prevent diseases. Nanomedicine involves the use of nanoscale materials, devices, or systems for medical applications. These can include drug delivery systems that target specific cells or tissues, diagnostic tools that detect biomarkers at the molecular level, and tissue engineering strategies that promote regeneration and repair.

While nanotechnology holds great promise for medicine, it is still a relatively new field with many challenges to overcome, including issues related to safety, regulation, and scalability.

Biomechanics is the application of mechanical laws to living structures and systems, particularly in the field of medicine and healthcare. A biomechanical phenomenon refers to a observable event or occurrence that involves the interaction of biological tissues or systems with mechanical forces. These phenomena can be studied at various levels, from the molecular and cellular level to the tissue, organ, and whole-body level.

Examples of biomechanical phenomena include:

1. The way that bones and muscles work together to produce movement (known as joint kinematics).
2. The mechanical behavior of biological tissues such as bone, cartilage, tendons, and ligaments under various loads and stresses.
3. The response of cells and tissues to mechanical stimuli, such as the way that bone tissue adapts to changes in loading conditions (known as Wolff's law).
4. The biomechanics of injury and disease processes, such as the mechanisms of joint injury or the development of osteoarthritis.
5. The use of mechanical devices and interventions to treat medical conditions, such as orthopedic implants or assistive devices for mobility impairments.

Understanding biomechanical phenomena is essential for developing effective treatments and prevention strategies for a wide range of medical conditions, from musculoskeletal injuries to neurological disorders.

Nanostructures, in the context of medical and biomedical research, refer to materials or devices with structural features that have at least one dimension ranging between 1-100 nanometers (nm). At this size scale, the properties of these structures can differ significantly from bulk materials, exhibiting unique phenomena that are often influenced by quantum effects.

Nanostructures have attracted considerable interest in biomedicine due to their potential applications in various areas such as drug delivery, diagnostics, regenerative medicine, and tissue engineering. They can be fabricated from a wide range of materials including metals, polymers, ceramics, and carbon-based materials.

Some examples of nanostructures used in biomedicine include:

1. Nanoparticles: These are tiny particles with at least one dimension in the nanoscale range. They can be made from various materials like metals, polymers, or lipids and have applications in drug delivery, imaging, and diagnostics.
2. Quantum dots: These are semiconductor nanocrystals that exhibit unique optical properties due to quantum confinement effects. They are used as fluorescent labels for bioimaging and biosensing applications.
3. Carbon nanotubes: These are hollow, cylindrical structures made of carbon atoms arranged in a hexagonal lattice. They have exceptional mechanical strength, electrical conductivity, and thermal stability, making them suitable for various biomedical applications such as drug delivery, tissue engineering, and biosensors.
4. Nanofibers: These are elongated nanostructures with high aspect ratios (length much greater than width). They can be fabricated from various materials like polymers, ceramics, or composites and have applications in tissue engineering, wound healing, and drug delivery.
5. Dendrimers: These are highly branched, nanoscale polymers with a well-defined structure and narrow size distribution. They can be used as drug carriers, gene delivery vehicles, and diagnostic agents.
6. Nanoshells: These are hollow, spherical nanoparticles consisting of a dielectric core covered by a thin metallic shell. They exhibit unique optical properties that make them suitable for applications such as photothermal therapy, biosensing, and imaging.

Biophysics is a interdisciplinary field that combines the principles and methods of physics with those of biology to study biological systems and phenomena. It involves the use of physical theories, models, and techniques to understand and explain the properties, functions, and behaviors of living organisms and their constituents, such as cells, proteins, and DNA.

Biophysics can be applied to various areas of biology, including molecular biology, cell biology, neuroscience, and physiology. It can help elucidate the mechanisms of biological processes at the molecular and cellular levels, such as protein folding, ion transport, enzyme kinetics, gene expression, and signal transduction. Biophysical methods can also be used to develop diagnostic and therapeutic tools for medical applications, such as medical imaging, drug delivery, and gene therapy.

Examples of biophysical techniques include X-ray crystallography, nuclear magnetic resonance (NMR) spectroscopy, electron microscopy, fluorescence microscopy, atomic force microscopy, and computational modeling. These methods allow researchers to probe the structure, dynamics, and interactions of biological molecules and systems with high precision and resolution, providing insights into their functions and behaviors.

The Elastic Modulus, also known as Young's modulus, is a measure of the stiffness of a material. It is defined as the ratio of stress (force per unit area) to strain (partial deformation or change in length per unit length) in the elastic range of deformation of a material. In other words, it measures how much a material will deform (change in length or size) when subjected to a given amount of force. A higher elastic modulus indicates that a material is stiffer and less likely to deform, while a lower elastic modulus indicates that a material is more flexible and will deform more easily. The elastic modulus is typically expressed in units of Pascals (Pa) or Gigapascals (GPa).

Immunoelectron microscopy (IEM) is a specialized type of electron microscopy that combines the principles of immunochemistry and electron microscopy to detect and localize specific antigens within cells or tissues at the ultrastructural level. This technique allows for the visualization and identification of specific proteins, viruses, or other antigenic structures with a high degree of resolution and specificity.

In IEM, samples are first fixed, embedded, and sectioned to prepare them for electron microscopy. The sections are then treated with specific antibodies that have been labeled with electron-dense markers, such as gold particles or ferritin. These labeled antibodies bind to the target antigens in the sample, allowing for their visualization under an electron microscope.

There are several different methods of IEM, including pre-embedding and post-embedding techniques. Pre-embedding involves labeling the antigens before embedding the sample in resin, while post-embedding involves labeling the antigens after embedding. Post-embedding techniques are generally more commonly used because they allow for better preservation of ultrastructure and higher resolution.

IEM is a valuable tool in many areas of research, including virology, bacteriology, immunology, and cell biology. It can be used to study the structure and function of viruses, bacteria, and other microorganisms, as well as the distribution and localization of specific proteins and antigens within cells and tissues.

A lipid bilayer is a thin membrane made up of two layers of lipid molecules, primarily phospholipids. The hydrophilic (water-loving) heads of the lipids face outwards, coming into contact with watery environments on both sides, while the hydrophobic (water-fearing) tails point inward, away from the aqueous surroundings. This unique structure allows lipid bilayers to form a stable barrier that controls the movement of molecules and ions in and out of cells and organelles, thus playing a crucial role in maintaining cellular compartmentalization and homeostasis.

Micromanipulation is a term used in the field of medicine, specifically in assisted reproductive technologies (ARTs) such as in vitro fertilization (IVF). It refers to a technique that involves the manipulation of oocytes (human eggs), sperm, and/or embryos under a microscope using micromanipulative tools and equipment.

The most common form of micromanipulation is intracytoplasmic sperm injection (ICSI), where a single sperm is selected and injected directly into the cytoplasm of an oocyte to facilitate fertilization. Other forms of micromanipulation include assisted hatching (AH), where a small opening is made in the zona pellucida (the protective layer surrounding the embryo) to help the embryo hatch and implant into the uterus, and embryo biopsy, which involves removing one or more cells from an embryo for genetic testing.

Micromanipulation requires specialized training and equipment and is typically performed in IVF laboratories by experienced embryologists. The goal of micromanipulation is to improve the chances of successful fertilization, implantation, and pregnancy, particularly in cases where conventional methods have been unsuccessful or when there are specific fertility issues, such as male factor infertility or genetic disorders.

I'm sorry for any confusion, but "mechanical processes" is not a specific medical term. However, in a broader scientific context, mechanical processes refer to actions or events that involve forces and the movement or conversion of energy. This could include physical movements or manipulations of the body or bodily systems, such as surgical procedures, or the functioning of mechanical medical devices like pacemakers. If you have a more specific context in mind, I'd be happy to help further!

Biophysical phenomena refer to the observable events and processes that occur in living organisms, which can be explained and studied using the principles and methods of physics. These phenomena can include a wide range of biological processes at various levels of organization, from molecular interactions to whole-organism behaviors. Examples of biophysical phenomena include the mechanics of muscle contraction, the electrical activity of neurons, the transport of molecules across cell membranes, and the optical properties of biological tissues. By applying physical theories and techniques to the study of living systems, biophysicists seek to better understand the fundamental principles that govern life and to develop new approaches for diagnosing and treating diseases.

Cryo-electron microscopy (Cryo-EM) is a type of electron microscopy where the sample is studied at cryogenic temperatures, typically liquid nitrogen temperatures. This technique is used to investigate the structure and shape of biological molecules and complexes, viruses, and other nanoscale particles.

In Cryo-EM, the sample is rapidly frozen to preserve its natural structure and then imaged using a beam of electrons. The images are collected at different angles and then computationally combined to generate a 3D reconstruction of the sample. This technique allows researchers to visualize biological structures in their native environment with near-atomic resolution, providing valuable insights into their function and behavior.

Cryo-EM has become an increasingly popular tool in structural biology due to its ability to image large and complex structures that are difficult or impossible to crystallize for X-ray crystallography. It has been used to determine the structures of many important biological molecules, including membrane proteins, ribosomes, viruses, and protein complexes involved in various cellular processes.

Scanning probe microscopy (SPM) is a type of microscopy that uses a physical probe to scan the surface of a sample and gather information about its topography and other properties. In SPM, a sharp tip attached to a flexible cantilever is brought very close to the sample surface, and as the tip scans across the surface, interactions between the tip and the sample cause the cantilever to deflect. This deflection is measured and used to generate an image of the sample's surface topography.

There are several types of SPM, including atomic force microscopy (AFM), scanning tunneling microscopy (STM), and near-field scanning optical microscopy (NSOM). These techniques can provide very high resolution images of surfaces at the atomic or molecular level, making them useful for studying a wide range of materials, from biological samples to semiconductors.

In summary, scanning probe microscopy is a powerful tool in materials science and biology that allows researchers to visualize and measure the properties of surfaces with very high resolution.

The term "Purple Membrane" is used in the context of medical research and biochemistry to refer to a specific structure within certain types of cells. It's not a commonly used term in general clinical medicine, but it does have significance in specific areas of study.

In a medical definition, Purple Membrane refers to a specialized portion of the cell membrane found in certain halobacteria (salt-loving bacteria). This membrane is called "purple" because it contains a light-absorbing pigment-protein complex called bacteriorhodopsin, which appears purple. Bacteriorhodopsin plays a crucial role in energy production for the cell by converting light energy into chemical energy through a process called chemiosmosis.

It's important to note that this term is highly specialized and not something that would typically come up in routine medical practice or patient care.

Bite force refers to the amount of force or pressure that can be exerted by the teeth and jaw when biting down or clenching together. It is a measure of an individual's maximum biting strength, typically expressed in units such as pounds (lb) or newtons (N). Bite force is an important factor in various biological and medical contexts, including oral health, nutrition, and the study of animal behavior and evolution.

In humans, bite force can vary widely depending on factors such as age, sex, muscle strength, and dental health. On average, a healthy adult human male may have a maximum bite force of around 150-200 pounds (670-890 newtons), while an adult female may have a bite force of around 100-130 pounds (445-578 newtons). However, these values can vary significantly from person to person.

Abnormalities in bite force can be indicative of various medical conditions or injuries, such as temporomandibular joint disorders (TMD), muscle weakness, or neurological disorders affecting the facial muscles. Assessing and measuring bite force may also be useful in evaluating the effectiveness of dental treatments or appliances, such as dentures or orthodontic devices.

Fluorescence microscopy is a type of optical microscopy that uses fluorescent probes to highlight and visualize specific components or structures within a sample. When these probes are excited by light of a specific wavelength, they emit light at longer wavelengths, creating a bright contrast against the dark background. This allows for high-resolution imaging of cells, tissues, and subcellular structures.

Multiphoton microscopy is a type of fluorescence microscopy that uses multiple photons of lower energy to excite the fluorophores, rather than a single high-energy photon. This technique offers several advantages over traditional fluorescence microscopy, including reduced photodamage and improved depth penetration in thick samples. Additionally, multiphoton microscopy can be used for techniques such as second harmonic generation (SHG) and third harmonic generation (THG), which provide additional contrast mechanisms for imaging.

In summary, fluorescence multiphoton microscopy is a powerful tool for high-resolution imaging of biological samples, offering improved depth penetration, reduced photodamage, and additional contrast mechanisms compared to traditional fluorescence microscopy.

Adsorption is a process in which atoms, ions, or molecules from a gas, liquid, or dissolved solid accumulate on the surface of a material. This occurs because the particles in the adsorbate (the substance being adsorbed) have forces that attract them to the surface of the adsorbent (the material that the adsorbate is adhering to).

In medical terms, adsorption can refer to the use of materials with adsorptive properties to remove harmful substances from the body. For example, activated charcoal is sometimes used in the treatment of poisoning because it can adsorb a variety of toxic substances and prevent them from being absorbed into the bloodstream.

It's important to note that adsorption is different from absorption, which refers to the process by which a substance is taken up and distributed throughout a material or tissue.

Scanning transmission electron microscopy (STEM) is a type of electron microscopy that uses a focused beam of electrons to transmit through a specimen and create an image based on the interactions between the electrons and the sample. In STEM, the electron beam is scanned across the sample in a raster pattern, similar to how a television or computer monitor displays an image. As the electrons pass through the sample, they interact with the atoms in the material, causing scattering and energy loss. By detecting these scattered and energy-loss electrons, a high-resolution image of the sample can be created.

Scanning transmission electron microscopy is particularly useful for imaging thin specimens with high resolution, making it an important tool in materials science, biology, and other fields where detailed information about the structure and composition of materials is needed. The technique can provide information about the crystal structure, chemical composition, and electronic properties of materials at the atomic level.

Overall, scanning transmission electron microscopy is a powerful tool for characterizing materials and understanding their properties at the nanoscale and atomic level.

Molecular models are three-dimensional representations of molecular structures that are used in the field of molecular biology and chemistry to visualize and understand the spatial arrangement of atoms and bonds within a molecule. These models can be physical or computer-generated and allow researchers to study the shape, size, and behavior of molecules, which is crucial for understanding their function and interactions with other molecules.

Physical molecular models are often made up of balls (representing atoms) connected by rods or sticks (representing bonds). These models can be constructed manually using materials such as plastic or wooden balls and rods, or they can be created using 3D printing technology.

Computer-generated molecular models, on the other hand, are created using specialized software that allows researchers to visualize and manipulate molecular structures in three dimensions. These models can be used to simulate molecular interactions, predict molecular behavior, and design new drugs or chemicals with specific properties. Overall, molecular models play a critical role in advancing our understanding of molecular structures and their functions.

Video microscopy is a medical technique that involves the use of a microscope equipped with a video camera to capture and display real-time images of specimens on a monitor. This allows for the observation and documentation of dynamic processes, such as cell movement or chemical reactions, at a level of detail that would be difficult or impossible to achieve with the naked eye. Video microscopy can also be used in conjunction with image analysis software to measure various parameters, such as size, shape, and motion, of individual cells or structures within the specimen.

There are several types of video microscopy, including brightfield, darkfield, phase contrast, fluorescence, and differential interference contrast (DIC) microscopy. Each type uses different optical techniques to enhance contrast and reveal specific features of the specimen. For example, fluorescence microscopy uses fluorescent dyes or proteins to label specific structures within the specimen, allowing them to be visualized against a dark background.

Video microscopy is used in various fields of medicine, including pathology, microbiology, and neuroscience. It can help researchers and clinicians diagnose diseases, study disease mechanisms, develop new therapies, and understand fundamental biological processes at the cellular and molecular level.

In the context of medical and health sciences, particle size generally refers to the diameter or dimension of particles, which can be in the form of solid particles, droplets, or aerosols. These particles may include airborne pollutants, pharmaceutical drugs, or medical devices such as nanoparticles used in drug delivery systems.

Particle size is an important factor to consider in various medical applications because it can affect the behavior and interactions of particles with biological systems. For example, smaller particle sizes can lead to greater absorption and distribution throughout the body, while larger particle sizes may be filtered out by the body's natural defense mechanisms. Therefore, understanding particle size and its implications is crucial for optimizing the safety and efficacy of medical treatments and interventions.

A cell membrane, also known as the plasma membrane, is a thin semi-permeable phospholipid bilayer that surrounds all cells in animals, plants, and microorganisms. It functions as a barrier to control the movement of substances in and out of the cell, allowing necessary molecules such as nutrients, oxygen, and signaling molecules to enter while keeping out harmful substances and waste products. The cell membrane is composed mainly of phospholipids, which have hydrophilic (water-loving) heads and hydrophobic (water-fearing) tails. This unique structure allows the membrane to be flexible and fluid, yet selectively permeable. Additionally, various proteins are embedded in the membrane that serve as channels, pumps, receptors, and enzymes, contributing to the cell's overall functionality and communication with its environment.

Connectin is also known as titin, which is a giant protein that plays a crucial role in the elasticity and stiffness of muscle fibers. It is the largest protein in humans, spanning half the length of a muscle cell's sarcomere, the basic unit of muscle contraction. Connectin/titin has several domains with different functions, including binding to other proteins, regulating muscle contraction, and signaling within the muscle cell. Mutations in the connectin/titin gene have been associated with various forms of muscular dystrophy and cardiomyopathy.

Photoelectron Spectroscopy (PES) is not typically considered a medical definition, but it is a term used in physical and analytical chemistry. However, I can provide a definition for you:

Photoelectron Spectroscopy (PES) is a technique used to study the electronic structure of atoms, molecules, and solids by irradiating them with photons (usually from a laser or a synchrotron light source) and measuring the kinetic energy of the ejected electrons. The technique provides information about the energy levels of the electrons in the sample, which can be used to determine its chemical composition, bonding, and electronic structure. PES is a valuable tool in surface science, materials research, and environmental analysis.

1,2-Dipalmitoylphosphatidylcholine (DPPC) is a type of phospholipid molecule that is a major component of the lipid bilayer in biological membranes, particularly in lung surfactant. It is composed of two palmitic acid chains attached to a glycerol backbone, which is linked to a phosphate group and a choline headgroup. The chemical formula for DPPC is C44H86NO8P.

In the body, DPPC plays an important role in maintaining the structure and function of cell membranes, as well as reducing surface tension in the lungs. It is also used in research and medical settings as a component of liposomes, which are used for drug delivery and other biomedical applications.

Protein binding, in the context of medical and biological sciences, refers to the interaction between a protein and another molecule (known as the ligand) that results in a stable complex. This process is often reversible and can be influenced by various factors such as pH, temperature, and concentration of the involved molecules.

In clinical chemistry, protein binding is particularly important when it comes to drugs, as many of them bind to proteins (especially albumin) in the bloodstream. The degree of protein binding can affect a drug's distribution, metabolism, and excretion, which in turn influence its therapeutic effectiveness and potential side effects.

Protein-bound drugs may be less available for interaction with their target tissues, as only the unbound or "free" fraction of the drug is active. Therefore, understanding protein binding can help optimize dosing regimens and minimize adverse reactions.

Mechanical stress, in the context of physiology and medicine, refers to any type of force that is applied to body tissues or organs, which can cause deformation or displacement of those structures. Mechanical stress can be either external, such as forces exerted on the body during physical activity or trauma, or internal, such as the pressure changes that occur within blood vessels or other hollow organs.

Mechanical stress can have a variety of effects on the body, depending on the type, duration, and magnitude of the force applied. For example, prolonged exposure to mechanical stress can lead to tissue damage, inflammation, and chronic pain. Additionally, abnormal or excessive mechanical stress can contribute to the development of various musculoskeletal disorders, such as tendinitis, osteoarthritis, and herniated discs.

In order to mitigate the negative effects of mechanical stress, the body has a number of adaptive responses that help to distribute forces more evenly across tissues and maintain structural integrity. These responses include changes in muscle tone, joint positioning, and connective tissue stiffness, as well as the remodeling of bone and other tissues over time. However, when these adaptive mechanisms are overwhelmed or impaired, mechanical stress can become a significant factor in the development of various pathological conditions.

Molecular conformation, also known as spatial arrangement or configuration, refers to the specific three-dimensional shape and orientation of atoms that make up a molecule. It describes the precise manner in which bonds between atoms are arranged around a molecular framework, taking into account factors such as bond lengths, bond angles, and torsional angles.

Conformational isomers, or conformers, are different spatial arrangements of the same molecule that can interconvert without breaking chemical bonds. These isomers may have varying energies, stability, and reactivity, which can significantly impact a molecule's biological activity and function. Understanding molecular conformation is crucial in fields such as drug design, where small changes in conformation can lead to substantial differences in how a drug interacts with its target.

Biological models, also known as physiological models or organismal models, are simplified representations of biological systems, processes, or mechanisms that are used to understand and explain the underlying principles and relationships. These models can be theoretical (conceptual or mathematical) or physical (such as anatomical models, cell cultures, or animal models). They are widely used in biomedical research to study various phenomena, including disease pathophysiology, drug action, and therapeutic interventions.

Examples of biological models include:

1. Mathematical models: These use mathematical equations and formulas to describe complex biological systems or processes, such as population dynamics, metabolic pathways, or gene regulation networks. They can help predict the behavior of these systems under different conditions and test hypotheses about their underlying mechanisms.
2. Cell cultures: These are collections of cells grown in a controlled environment, typically in a laboratory dish or flask. They can be used to study cellular processes, such as signal transduction, gene expression, or metabolism, and to test the effects of drugs or other treatments on these processes.
3. Animal models: These are living organisms, usually vertebrates like mice, rats, or non-human primates, that are used to study various aspects of human biology and disease. They can provide valuable insights into the pathophysiology of diseases, the mechanisms of drug action, and the safety and efficacy of new therapies.
4. Anatomical models: These are physical representations of biological structures or systems, such as plastic models of organs or tissues, that can be used for educational purposes or to plan surgical procedures. They can also serve as a basis for developing more sophisticated models, such as computer simulations or 3D-printed replicas.

Overall, biological models play a crucial role in advancing our understanding of biology and medicine, helping to identify new targets for therapeutic intervention, develop novel drugs and treatments, and improve human health.

Protein conformation refers to the specific three-dimensional shape that a protein molecule assumes due to the spatial arrangement of its constituent amino acid residues and their associated chemical groups. This complex structure is determined by several factors, including covalent bonds (disulfide bridges), hydrogen bonds, van der Waals forces, and ionic bonds, which help stabilize the protein's unique conformation.

Protein conformations can be broadly classified into two categories: primary, secondary, tertiary, and quaternary structures. The primary structure represents the linear sequence of amino acids in a polypeptide chain. The secondary structure arises from local interactions between adjacent amino acid residues, leading to the formation of recurring motifs such as α-helices and β-sheets. Tertiary structure refers to the overall three-dimensional folding pattern of a single polypeptide chain, while quaternary structure describes the spatial arrangement of multiple folded polypeptide chains (subunits) that interact to form a functional protein complex.

Understanding protein conformation is crucial for elucidating protein function, as the specific three-dimensional shape of a protein directly influences its ability to interact with other molecules, such as ligands, nucleic acids, or other proteins. Any alterations in protein conformation due to genetic mutations, environmental factors, or chemical modifications can lead to loss of function, misfolding, aggregation, and disease states like neurodegenerative disorders and cancer.

Interference microscopy is a type of microscopy that uses the interference of light waves to enhance contrast and visualize details in a specimen. It is often used to measure thin transparent samples, such as cells or tissues, with very high precision. One common method of interference microscopy is phase contrast microscopy, which converts differences in the optical path length of light passing through the sample into changes in amplitude and/or phase of the transmitted light. This results in enhanced contrast and visibility of details that may be difficult to see using other forms of microscopy. Other types of interference microscopy include differential interference contrast (DIC) microscopy, which uses polarized light to enhance contrast, and holographic microscopy, which records and reconstructs the wavefront of light passing through the sample to create a 3D image.

Deoxyribonucleic acid (DNA) is the genetic material present in the cells of organisms where it is responsible for the storage and transmission of hereditary information. DNA is a long molecule that consists of two strands coiled together to form a double helix. Each strand is made up of a series of four nucleotide bases - adenine (A), guanine (G), cytosine (C), and thymine (T) - that are linked together by phosphate and sugar groups. The sequence of these bases along the length of the molecule encodes genetic information, with A always pairing with T and C always pairing with G. This base-pairing allows for the replication and transcription of DNA, which are essential processes in the functioning and reproduction of all living organisms.

Viscosity is a physical property of a fluid that describes its resistance to flow. In medical terms, viscosity is often discussed in relation to bodily fluids such as blood or synovial fluid (found in joints). The unit of measurement for viscosity is the poise, although it is more commonly expressed in millipascals-second (mPa.s) in SI units. Highly viscous fluids flow more slowly than less viscous fluids. Changes in the viscosity of bodily fluids can have significant implications for health and disease; for example, increased blood viscosity has been associated with cardiovascular diseases, while decreased synovial fluid viscosity can contribute to joint pain and inflammation in conditions like osteoarthritis.

Phase-contrast microscopy is a type of optical microscopy that allows visualization of transparent or translucent specimens, such as living cells and their organelles, by increasing the contrast between areas with different refractive indices within the sample. This technique works by converting phase shifts in light passing through the sample into changes in amplitude, which can then be observed as differences in brightness and contrast.

In a phase-contrast microscope, a special condenser and objective are used to create an optical path difference between the direct and diffracted light rays coming from the specimen. The condenser introduces a phase shift for the diffracted light, while the objective contains a phase ring that compensates for this shift in the direct light. This results in the direct light appearing brighter than the diffracted light, creating contrast between areas with different refractive indices within the sample.

Phase-contrast microscopy is particularly useful for observing unstained living cells and their dynamic processes, such as cell division, motility, and secretion, without the need for stains or dyes that might affect their viability or behavior.

'Adhesiveness' is a term used in medicine and biology to describe the ability of two surfaces to stick or adhere to each other. In medical terms, it often refers to the property of tissues or cells to adhere to one another, as in the case of scar tissue formation where healing tissue adheres to adjacent structures.

In the context of microbiology, adhesiveness can refer to the ability of bacteria or other microorganisms to attach themselves to surfaces, such as medical devices or human tissues, which can lead to infection and other health problems. Adhesives used in medical devices, such as bandages or wound dressings, also have adhesiveness properties that allow them to stick to the skin or other surfaces.

Overall, adhesiveness is an important property in many areas of medicine and biology, with implications for wound healing, infection control, and the design and function of medical devices.

In the context of medical definitions, polymers are large molecules composed of repeating subunits called monomers. These long chains of monomers can have various structures and properties, depending on the type of monomer units and how they are linked together. In medicine, polymers are used in a wide range of applications, including drug delivery systems, medical devices, and tissue engineering scaffolds. Some examples of polymers used in medicine include polyethylene, polypropylene, polystyrene, polyvinyl chloride (PVC), and biodegradable polymers such as polylactic acid (PLA) and polycaprolactone (PCL).

Membrane fluidity, in the context of cell biology, refers to the ability of the phospholipid bilayer that makes up the cell membrane to change its structure and organization in response to various factors. The membrane is not a static structure but rather a dynamic one, with its lipids constantly moving and changing position.

Membrane fluidity is determined by the fatty acid composition of the phospholipids that make up the bilayer. Lipids with unsaturated fatty acids have kinks in their hydrocarbon chains, which prevent them from packing closely together and increase membrane fluidity. In contrast, lipids with saturated fatty acids can pack closely together, reducing membrane fluidity.

Membrane fluidity is important for various cellular processes, including the movement of proteins within the membrane, the fusion of vesicles with the membrane during exocytosis and endocytosis, and the ability of the membrane to respond to changes in temperature and other environmental factors. Abnormalities in membrane fluidity have been linked to various diseases, including cancer, neurological disorders, and infectious diseases.

I believe there may be some confusion in your question. Gold is typically a chemical element with the symbol Au and atomic number 79. It is a dense, soft, malleable, and ductile metal. It is one of the least reactive chemical elements and is solid under standard conditions.

However, if you are referring to "Gold" in the context of medical terminology, it may refer to:

1. Gold salts: These are a group of compounds that contain gold and are used in medicine for their anti-inflammatory properties. They have been used in the treatment of rheumatoid arthritis, although they have largely been replaced by newer drugs with fewer side effects.
2. Gold implants: In some cases, a small amount of gold may be surgically implanted into the eye to treat conditions such as age-related macular degeneration or diabetic retinopathy. The gold helps to hold the retina in place and can improve vision in some patients.
3. Gold thread embedment: This is an alternative therapy used in traditional Chinese medicine, where gold threads are embedded into the skin or acupuncture points for therapeutic purposes. However, there is limited scientific evidence to support its effectiveness.

I hope this information helps! If you have any further questions, please let me know.

Polarized light microscopy is a type of microscopy that uses polarized light to enhance contrast and reveal unique optical properties in specimens. In this technique, a polarizing filter is placed under the light source, which polarizes the light as it passes through. The specimen is then illuminated with this linearly polarized light. As the light travels through the specimen, its plane of polarization may be altered due to birefringence, a property of certain materials that causes the light to split into two separate rays with different refractive indices.

A second polarizing filter, called an analyzer, is placed in the light path between the objective and the eyepiece. The orientation of this filter can be adjusted to either allow or block the transmission of light through the microscope. When the polarizer and analyzer are aligned perpendicularly, no light will pass through if the specimen does not exhibit birefringence. However, if the specimen has birefringent properties, it will cause the plane of polarization to rotate, allowing some light to pass through the analyzer and create a contrasting image.

Polarized light microscopy is particularly useful for observing structures in minerals, crystals, and certain biological materials like collagen fibers, muscle proteins, and starch granules. It can also be used to study stress patterns in plastics and other synthetic materials.

Artificial membranes are synthetic or man-made materials that possess properties similar to natural biological membranes, such as selective permeability and barrier functions. These membranes can be designed to control the movement of molecules, ions, or cells across them, making them useful in various medical and biotechnological applications.

Examples of artificial membranes include:

1. Dialysis membranes: Used in hemodialysis for patients with renal failure, these semi-permeable membranes filter waste products and excess fluids from the blood while retaining essential proteins and cells.
2. Hemofiltration membranes: Utilized in extracorporeal circuits to remove larger molecules, such as cytokines or inflammatory mediators, from the blood during critical illnesses or sepsis.
3. Drug delivery systems: Artificial membranes can be used to encapsulate drugs, allowing for controlled release and targeted drug delivery in specific tissues or cells.
4. Tissue engineering: Synthetic membranes serve as scaffolds for cell growth and tissue regeneration, guiding the formation of new functional tissues.
5. Biosensors: Artificial membranes can be integrated into biosensing devices to selectively detect and quantify biomolecules, such as proteins or nucleic acids, in diagnostic applications.
6. Microfluidics: Artificial membranes are used in microfluidic systems for lab-on-a-chip applications, enabling the manipulation and analysis of small volumes of fluids for various medical and biological purposes.

Protein multimerization refers to the process where multiple protein subunits assemble together to form a complex, repetitive structure called a multimer or oligomer. This can involve the association of identical or similar protein subunits through non-covalent interactions such as hydrogen bonding, ionic bonding, and van der Waals forces. The resulting multimeric structures can have various shapes, sizes, and functions, including enzymatic activity, transport, or structural support. Protein multimerization plays a crucial role in many biological processes and is often necessary for the proper functioning of proteins within cells.

In the context of medicine, "mechanics" is not typically used as a standalone term with a widely accepted or specific definition. However, in certain areas such as biomechanics or orthopedic mechanics, it generally refers to the application of mechanical principles and laws to biological systems, tissues, or organs. This can include studying the forces, movements, and deformations that occur within these systems, as well as designing medical devices or treatments based on an understanding of these mechanical properties.

In the field of medicine, "time factors" refer to the duration of symptoms or time elapsed since the onset of a medical condition, which can have significant implications for diagnosis and treatment. Understanding time factors is crucial in determining the progression of a disease, evaluating the effectiveness of treatments, and making critical decisions regarding patient care.

For example, in stroke management, "time is brain," meaning that rapid intervention within a specific time frame (usually within 4.5 hours) is essential to administering tissue plasminogen activator (tPA), a clot-busting drug that can minimize brain damage and improve patient outcomes. Similarly, in trauma care, the "golden hour" concept emphasizes the importance of providing definitive care within the first 60 minutes after injury to increase survival rates and reduce morbidity.

Time factors also play a role in monitoring the progression of chronic conditions like diabetes or heart disease, where regular follow-ups and assessments help determine appropriate treatment adjustments and prevent complications. In infectious diseases, time factors are crucial for initiating antibiotic therapy and identifying potential outbreaks to control their spread.

Overall, "time factors" encompass the significance of recognizing and acting promptly in various medical scenarios to optimize patient outcomes and provide effective care.

I'm happy to help! However, I must clarify that "materials testing" is not a medical term per se. It is a term used in various fields, including engineering and materials science, to describe the process of subjecting materials to different tests to evaluate their properties and performance under various conditions.

In the context of medical devices or implants, materials testing may refer to the evaluation of the physical and mechanical properties of materials used in their construction. These tests can include assessments of strength, durability, biocompatibility, and other factors that are critical to ensuring the safety and efficacy of medical devices.

Medical device manufacturers must comply with regulatory standards for materials testing to ensure that their products meet specific requirements for performance, safety, and quality. These standards may vary depending on the type of device, its intended use, and the country or region in which it will be marketed and sold.

I'm sorry for any confusion, but "graphite" is not a medical term. It is a mineral form of carbon that is used in various applications, such as pencils, lubricants, and batteries. If you have any medical questions or terms you would like defined, I'd be happy to help!

Fluorescent dyes are substances that emit light upon excitation by absorbing light of a shorter wavelength. In a medical context, these dyes are often used in various diagnostic tests and procedures to highlight or mark certain structures or substances within the body. For example, fluorescent dyes may be used in imaging techniques such as fluorescence microscopy or fluorescence angiography to help visualize cells, tissues, or blood vessels. These dyes can also be used in flow cytometry to identify and sort specific types of cells. The choice of fluorescent dye depends on the specific application and the desired properties, such as excitation and emission spectra, quantum yield, and photostability.

Amyloid is a term used in medicine to describe abnormally folded protein deposits that can accumulate in various tissues and organs of the body. These misfolded proteins can form aggregates known as amyloid fibrils, which have a characteristic beta-pleated sheet structure. Amyloid deposits can be composed of different types of proteins, depending on the specific disease associated with the deposit.

In some cases, amyloid deposits can cause damage to organs and tissues, leading to various clinical symptoms. Some examples of diseases associated with amyloidosis include Alzheimer's disease (where amyloid-beta protein accumulates in the brain), systemic amyloidosis (where amyloid fibrils deposit in various organs such as the heart, kidneys, and liver), and type 2 diabetes (where amyloid deposits form in the pancreas).

It's important to note that not all amyloid deposits are harmful or associated with disease. However, when they do cause problems, treatment typically involves managing the underlying condition that is leading to the abnormal protein accumulation.

A computer simulation is a process that involves creating a model of a real-world system or phenomenon on a computer and then using that model to run experiments and make predictions about how the system will behave under different conditions. In the medical field, computer simulations are used for a variety of purposes, including:

1. Training and education: Computer simulations can be used to create realistic virtual environments where medical students and professionals can practice their skills and learn new procedures without risk to actual patients. For example, surgeons may use simulation software to practice complex surgical techniques before performing them on real patients.
2. Research and development: Computer simulations can help medical researchers study the behavior of biological systems at a level of detail that would be difficult or impossible to achieve through experimental methods alone. By creating detailed models of cells, tissues, organs, or even entire organisms, researchers can use simulation software to explore how these systems function and how they respond to different stimuli.
3. Drug discovery and development: Computer simulations are an essential tool in modern drug discovery and development. By modeling the behavior of drugs at a molecular level, researchers can predict how they will interact with their targets in the body and identify potential side effects or toxicities. This information can help guide the design of new drugs and reduce the need for expensive and time-consuming clinical trials.
4. Personalized medicine: Computer simulations can be used to create personalized models of individual patients based on their unique genetic, physiological, and environmental characteristics. These models can then be used to predict how a patient will respond to different treatments and identify the most effective therapy for their specific condition.

Overall, computer simulations are a powerful tool in modern medicine, enabling researchers and clinicians to study complex systems and make predictions about how they will behave under a wide range of conditions. By providing insights into the behavior of biological systems at a level of detail that would be difficult or impossible to achieve through experimental methods alone, computer simulations are helping to advance our understanding of human health and disease.

I'm sorry for any confusion, but "Glass" is not a medical term. Glass is a non-crystalline amorphous solid that is often transparent and has various uses in everyday life, including medical devices and equipment. If you have any questions related to medical terminology or concepts, please provide them, and I'll be happy to help.

Actin is a type of protein that forms part of the contractile apparatus in muscle cells, and is also found in various other cell types. It is a globular protein that polymerizes to form long filaments, which are important for many cellular processes such as cell division, cell motility, and the maintenance of cell shape. In muscle cells, actin filaments interact with another type of protein called myosin to enable muscle contraction. Actins can be further divided into different subtypes, including alpha-actin, beta-actin, and gamma-actin, which have distinct functions and expression patterns in the body.

In the context of medical terminology, "solutions" refers to a homogeneous mixture of two or more substances, in which one substance (the solute) is uniformly distributed within another substance (the solvent). The solvent is typically the greater component of the solution and is capable of dissolving the solute.

Solutions can be classified based on the physical state of the solvent and solute. For instance, a solution in which both the solvent and solute are liquids is called a liquid solution or simply a solution. A solid solution is one where the solvent is a solid and the solute is either a gas, liquid, or solid. Similarly, a gas solution refers to a mixture where the solvent is a gas and the solute can be a gas, liquid, or solid.

In medical applications, solutions are often used as vehicles for administering medications, such as intravenous (IV) fluids, oral rehydration solutions, eye drops, and topical creams or ointments. The composition of these solutions is carefully controlled to ensure the appropriate concentration and delivery of the active ingredients.

A chemical model is a simplified representation or description of a chemical system, based on the laws of chemistry and physics. It is used to explain and predict the behavior of chemicals and chemical reactions. Chemical models can take many forms, including mathematical equations, diagrams, and computer simulations. They are often used in research, education, and industry to understand complex chemical processes and develop new products and technologies.

For example, a chemical model might be used to describe the way that atoms and molecules interact in a particular reaction, or to predict the properties of a new material. Chemical models can also be used to study the behavior of chemicals at the molecular level, such as how they bind to each other or how they are affected by changes in temperature or pressure.

It is important to note that chemical models are simplifications of reality and may not always accurately represent every aspect of a chemical system. They should be used with caution and validated against experimental data whenever possible.

Optical tweezers, also known as optical traps or laser tweezers, refer to a scientific instrument that uses highly focused laser beams to manipulate and trap microscopic particles, typically smaller than a micron in diameter. The principle behind optical tweezers is the transfer of momentum between photons (light particles) and the particle being manipulated. When a laser beam is focused through a high numerical aperture objective lens, it creates an intense gradient force that attracts and holds the particle at the focus point, allowing researchers to precisely move and apply forces to the particle in three dimensions.

Optical tweezers have become an essential tool in various fields of biology, physics, and engineering due to their ability to manipulate and measure microscopic objects with high precision and non-invasively. In the medical field, optical tweezers are used for studying cell mechanics, molecular motors, DNA manipulation, protein folding, and other biological processes at the single-molecule level. Additionally, they have potential applications in diagnostics, therapeutics, and drug development by enabling the analysis of individual cells or biomolecules with unprecedented accuracy.

Computer-assisted image processing is a medical term that refers to the use of computer systems and specialized software to improve, analyze, and interpret medical images obtained through various imaging techniques such as X-ray, CT (computed tomography), MRI (magnetic resonance imaging), ultrasound, and others.

The process typically involves several steps, including image acquisition, enhancement, segmentation, restoration, and analysis. Image processing algorithms can be used to enhance the quality of medical images by adjusting contrast, brightness, and sharpness, as well as removing noise and artifacts that may interfere with accurate diagnosis. Segmentation techniques can be used to isolate specific regions or structures of interest within an image, allowing for more detailed analysis.

Computer-assisted image processing has numerous applications in medical imaging, including detection and characterization of lesions, tumors, and other abnormalities; assessment of organ function and morphology; and guidance of interventional procedures such as biopsies and surgeries. By automating and standardizing image analysis tasks, computer-assisted image processing can help to improve diagnostic accuracy, efficiency, and consistency, while reducing the potential for human error.

Cell adhesion refers to the binding of cells to extracellular matrices or to other cells, a process that is fundamental to the development, function, and maintenance of multicellular organisms. Cell adhesion is mediated by various cell surface receptors, such as integrins, cadherins, and immunoglobulin-like cell adhesion molecules (Ig-CAMs), which interact with specific ligands in the extracellular environment. These interactions lead to the formation of specialized junctions, such as tight junctions, adherens junctions, and desmosomes, that help to maintain tissue architecture and regulate various cellular processes, including proliferation, differentiation, migration, and survival. Disruptions in cell adhesion can contribute to a variety of diseases, including cancer, inflammation, and degenerative disorders.

The cytoskeleton is a complex network of various protein filaments that provides structural support, shape, and stability to the cell. It plays a crucial role in maintaining cellular integrity, intracellular organization, and enabling cell movement. The cytoskeleton is composed of three major types of protein fibers: microfilaments (actin filaments), intermediate filaments, and microtubules. These filaments work together to provide mechanical support, participate in cell division, intracellular transport, and help maintain the cell's architecture. The dynamic nature of the cytoskeleton allows cells to adapt to changing environmental conditions and respond to various stimuli.

Crystallization is a process in which a substance transitions from a liquid or dissolved state to a solid state, forming a crystal lattice. In the medical context, crystallization can refer to the formation of crystals within the body, which can occur under certain conditions such as changes in pH, temperature, or concentration of solutes. These crystals can deposit in various tissues and organs, leading to the formation of crystal-induced diseases or disorders.

For example, in patients with gout, uric acid crystals can accumulate in joints, causing inflammation, pain, and swelling. Similarly, in nephrolithiasis (kidney stones), minerals in the urine can crystallize and form stones that can obstruct the urinary tract. Crystallization can also occur in other medical contexts, such as in the formation of dental calculus or plaque, and in the development of cataracts in the eye.

Nanoparticles are defined in the field of medicine as tiny particles that have at least one dimension between 1 to 100 nanometers (nm). They are increasingly being used in various medical applications such as drug delivery, diagnostics, and therapeutics. Due to their small size, nanoparticles can penetrate cells, tissues, and organs more efficiently than larger particles, making them ideal for targeted drug delivery and imaging.

Nanoparticles can be made from a variety of materials including metals, polymers, lipids, and dendrimers. The physical and chemical properties of nanoparticles, such as size, shape, charge, and surface chemistry, can greatly affect their behavior in biological systems and their potential medical applications.

It is important to note that the use of nanoparticles in medicine is still a relatively new field, and there are ongoing studies to better understand their safety and efficacy.

Nucleic acid conformation refers to the three-dimensional structure that nucleic acids (DNA and RNA) adopt as a result of the bonding patterns between the atoms within the molecule. The primary structure of nucleic acids is determined by the sequence of nucleotides, while the conformation is influenced by factors such as the sugar-phosphate backbone, base stacking, and hydrogen bonding.

Two common conformations of DNA are the B-form and the A-form. The B-form is a right-handed helix with a diameter of about 20 Å and a pitch of 34 Å, while the A-form has a smaller diameter (about 18 Å) and a shorter pitch (about 25 Å). RNA typically adopts an A-form conformation.

The conformation of nucleic acids can have significant implications for their function, as it can affect their ability to interact with other molecules such as proteins or drugs. Understanding the conformational properties of nucleic acids is therefore an important area of research in molecular biology and medicine.

I'm sorry for any confusion, but "mechanical phenomena" is not a standard medical term. The term "mechanical phenomenon" is more commonly used in the fields of physics and engineering to refer to events or processes that involve physical forces and movements, such as the movement of a lever or the flow of a fluid due to pressure differences.

If you have any questions about a specific medical concept or condition, I would be happy to try to help you with that instead!

Cellular mechanotransduction is the process by which cells convert mechanical stimuli into biochemical signals, resulting in changes in cell behavior and function. This complex process involves various molecular components, including transmembrane receptors, ion channels, cytoskeletal proteins, and signaling molecules. Mechanical forces such as tension, compression, or fluid flow can activate these components, leading to alterations in gene expression, protein synthesis, and cell shape or movement. Cellular mechanotransduction plays a crucial role in various physiological processes, including tissue development, homeostasis, and repair, as well as in pathological conditions such as fibrosis and cancer progression.

Polylysine is not a medical term per se, but it is a term used in biochemistry and medicine. Polylysine refers to a synthetic polymer of the amino acid lysine, which is linked together by peptide bonds to form a long, unbranched chain. It is often used in laboratory settings as a tool for scientific research, particularly in the study of protein-protein interactions and cellular uptake mechanisms.

In medicine, polylysine has been explored as a potential drug delivery vehicle, as it can be chemically modified to carry drugs or other therapeutic agents into cells. However, its use in clinical settings is not yet widespread. It's important to note that the term 'polylysine' itself does not have a specific medical definition, but rather refers to a class of biochemical compounds with certain properties.

Muscle contraction is the physiological process in which muscle fibers shorten and generate force, leading to movement or stability of a body part. This process involves the sliding filament theory where thick and thin filaments within the sarcomeres (the functional units of muscles) slide past each other, facilitated by the interaction between myosin heads and actin filaments. The energy required for this action is provided by the hydrolysis of adenosine triphosphate (ATP). Muscle contractions can be voluntary or involuntary, and they play a crucial role in various bodily functions such as locomotion, circulation, respiration, and posture maintenance.

"Cells, cultured" is a medical term that refers to cells that have been removed from an organism and grown in controlled laboratory conditions outside of the body. This process is called cell culture and it allows scientists to study cells in a more controlled and accessible environment than they would have inside the body. Cultured cells can be derived from a variety of sources, including tissues, organs, or fluids from humans, animals, or cell lines that have been previously established in the laboratory.

Cell culture involves several steps, including isolation of the cells from the tissue, purification and characterization of the cells, and maintenance of the cells in appropriate growth conditions. The cells are typically grown in specialized media that contain nutrients, growth factors, and other components necessary for their survival and proliferation. Cultured cells can be used for a variety of purposes, including basic research, drug development and testing, and production of biological products such as vaccines and gene therapies.

It is important to note that cultured cells may behave differently than they do in the body, and results obtained from cell culture studies may not always translate directly to human physiology or disease. Therefore, it is essential to validate findings from cell culture experiments using additional models and ultimately in clinical trials involving human subjects.

I'm sorry for any confusion, but "Silicon" does not have a specific medical definition. Silicon is a chemical element with the symbol Si and atomic number 14. It is a metalloid, which means it has properties of both metals and nonmetals. In the human body, silicon is not considered an essential nutrient, although it is found in trace amounts in various tissues. Some research suggests that silicon might play a role in collagen synthesis and bone health, but more studies are needed to confirm these findings and establish recommended intake levels.

Protein unfolding, also known as protein denaturation, refers to the loss of a protein's native structure, leading to a random or disordered conformation. Proteins are complex molecules that fold into specific three-dimensional shapes, allowing them to perform their biological functions. Various factors, such as heat, changes in pH, chemical denaturants, or mechanical forces, can disrupt the delicate balance of interactions that maintain this folded structure, causing the protein to unfold. Unfolded proteins may lose their functionality and can aggregate, forming insoluble aggregates, which can be harmful to cells and contribute to various diseases, including neurodegenerative disorders.

Tertiary protein structure refers to the three-dimensional arrangement of all the elements (polypeptide chains) of a single protein molecule. It is the highest level of structural organization and results from interactions between various side chains (R groups) of the amino acids that make up the protein. These interactions, which include hydrogen bonds, ionic bonds, van der Waals forces, and disulfide bridges, give the protein its unique shape and stability, which in turn determines its function. The tertiary structure of a protein can be stabilized by various factors such as temperature, pH, and the presence of certain ions. Any changes in these factors can lead to denaturation, where the protein loses its tertiary structure and thus its function.

"Cattle" is a term used in the agricultural and veterinary fields to refer to domesticated animals of the genus *Bos*, primarily *Bos taurus* (European cattle) and *Bos indicus* (Zebu). These animals are often raised for meat, milk, leather, and labor. They are also known as bovines or cows (for females), bulls (intact males), and steers/bullocks (castrated males). However, in a strict medical definition, "cattle" does not apply to humans or other animals.

A hardness test is a quantitative measure of a material's resistance to deformation, typically defined as the penetration of an indenter with a specific shape and load into the surface of the material being tested. There are several types of hardness tests, including Rockwell, Vickers, Brinell, and Knoop, each with their own specific methods and applications. The resulting hardness value is used to evaluate the material's properties, such as wear resistance, durability, and suitability for various industrial or manufacturing processes. Hardness tests are widely used in materials science, engineering, and quality control to ensure the consistency and reliability of materials and components.

Streptavidin is not a medical term per se, but rather a biochemical term used in the field of medicine and laboratory research. Streptavidin is a protein that is derived from the bacterium Streptomyces avidinii. It has a unique ability to bind very strongly and specifically to another molecule called biotin, with an association constant that is one of the strongest non-covalent interactions known in nature.

This property makes streptavidin a valuable tool in various medical and research applications such as immunoassays, histology, molecular biology, and drug delivery systems. For example, biotinylated molecules (such as antibodies, DNA, or enzymes) can be linked to streptavidin for detection, purification, or targeting purposes.

In summary, streptavidin is a bacterial protein that binds strongly and specifically to biotin, which is used in various medical and research applications as a tool for detection, purification, or targeting purposes.

I'm sorry for any confusion, but "spectrum analysis" is not a commonly used medical term. Spectrum analysis is a term that is more frequently used in the fields of physics, mathematics, and engineering to describe the process of breaking down a signal or a wave into its different frequencies and amplitudes, creating a visual representation called a spectrum.

If you have any concerns about a medical issue, I would recommend consulting with a healthcare professional for accurate information and guidance.

In the context of medicine and pharmacology, "kinetics" refers to the study of how a drug moves throughout the body, including its absorption, distribution, metabolism, and excretion (often abbreviated as ADME). This field is called "pharmacokinetics."

1. Absorption: This is the process of a drug moving from its site of administration into the bloodstream. Factors such as the route of administration (e.g., oral, intravenous, etc.), formulation, and individual physiological differences can affect absorption.

2. Distribution: Once a drug is in the bloodstream, it gets distributed throughout the body to various tissues and organs. This process is influenced by factors like blood flow, protein binding, and lipid solubility of the drug.

3. Metabolism: Drugs are often chemically modified in the body, typically in the liver, through processes known as metabolism. These changes can lead to the formation of active or inactive metabolites, which may then be further distributed, excreted, or undergo additional metabolic transformations.

4. Excretion: This is the process by which drugs and their metabolites are eliminated from the body, primarily through the kidneys (urine) and the liver (bile).

Understanding the kinetics of a drug is crucial for determining its optimal dosing regimen, potential interactions with other medications or foods, and any necessary adjustments for special populations like pediatric or geriatric patients, or those with impaired renal or hepatic function.

In the context of medical terminology, "hardness" is not a term that has a specific or standardized definition. It may be used in various ways to describe the firmness or consistency of a tissue, such as the hardness of an artery or tumor, but it does not have a single authoritative medical definition.

In some cases, healthcare professionals may use subjective terms like "hard," "firm," or "soft" to describe their tactile perception during a physical examination. For example, they might describe the hardness of an enlarged liver or spleen by comparing it to the feel of their knuckles when gently pressed against the abdomen.

However, in other contexts, healthcare professionals may use more objective measures of tissue stiffness or elasticity, such as palpation durometry or shear wave elastography, which provide quantitative assessments of tissue hardness. These techniques can be useful for diagnosing and monitoring conditions that affect the mechanical properties of tissues, such as liver fibrosis or cancer.

Therefore, while "hardness" may be a term used in medical contexts to describe certain physical characteristics of tissues, it does not have a single, universally accepted definition.

A phase transition in the context of medicine and physiology often refers to the transformation of a substance or matter from one state to another within the body, typically in relation to temperature or pressure changes. However, I couldn't find a widely accepted medical definition for "phase transition."

In physics and chemistry, a phase transition is a process where a thermodynamic system changes from one phase or state of matter to another, such as:

1. Solid to liquid (melting)
2. Liquid to gas (vaporization)
3. Gas to liquid (condensation)
4. Solid to gas (sublimation)
5. Changes between different crystalline structures of the same substance (polymorphic phase transitions)

While not a direct medical definition, these concepts are relevant in various biochemical and physiological processes, such as protein folding, cell membrane fluidity, and temperature regulation in the body.

Medical definitions of water generally describe it as a colorless, odorless, tasteless liquid that is essential for all forms of life. It is a universal solvent, making it an excellent medium for transporting nutrients and waste products within the body. Water constitutes about 50-70% of an individual's body weight, depending on factors such as age, sex, and muscle mass.

In medical terms, water has several important functions in the human body:

1. Regulation of body temperature through perspiration and respiration.
2. Acting as a lubricant for joints and tissues.
3. Facilitating digestion by helping to break down food particles.
4. Transporting nutrients, oxygen, and waste products throughout the body.
5. Helping to maintain healthy skin and mucous membranes.
6. Assisting in the regulation of various bodily functions, such as blood pressure and heart rate.

Dehydration can occur when an individual does not consume enough water or loses too much fluid due to illness, exercise, or other factors. This can lead to a variety of symptoms, including dry mouth, fatigue, dizziness, and confusion. Severe dehydration can be life-threatening if left untreated.

Fourier Transform Infrared (FTIR) spectroscopy is a type of infrared spectroscopy that uses the Fourier transform mathematical technique to convert the raw data obtained from an interferometer into a more interpretable spectrum. This technique allows for the simultaneous collection of a wide range of wavelengths, resulting in increased sensitivity and speed compared to traditional dispersive infrared spectroscopy.

FTIR spectroscopy measures the absorption or transmission of infrared radiation by a sample as a function of frequency, providing information about the vibrational modes of the molecules present in the sample. This can be used for identification and quantification of chemical compounds, analysis of molecular structure, and investigation of chemical interactions and reactions.

In summary, FTIR spectroscopy is a powerful analytical technique that uses infrared radiation to study the vibrational properties of molecules, with increased sensitivity and speed due to the use of Fourier transform mathematical techniques and an interferometer.

Membrane microdomains, also known as lipid rafts, are specialized microenvironments within the cell membrane. They are characterized by the presence of sphingolipids, cholesterol, and specific proteins that cluster together, forming dynamic, heterogeneous, and highly organized domains. These microdomains are involved in various cellular processes such as signal transduction, membrane trafficking, and pathogen entry. However, it's important to note that the existence and function of membrane microdomains are still subjects of ongoing research and debate within the scientific community.

Secondary protein structure refers to the local spatial arrangement of amino acid chains in a protein, typically described as regular repeating patterns held together by hydrogen bonds. The two most common types of secondary structures are the alpha-helix (α-helix) and the beta-pleated sheet (β-sheet). In an α-helix, the polypeptide chain twists around itself in a helical shape, with each backbone atom forming a hydrogen bond with the fourth amino acid residue along the chain. This forms a rigid rod-like structure that is resistant to bending or twisting forces. In β-sheets, adjacent segments of the polypeptide chain run parallel or antiparallel to each other and are connected by hydrogen bonds, forming a pleated sheet-like arrangement. These secondary structures provide the foundation for the formation of tertiary and quaternary protein structures, which determine the overall three-dimensional shape and function of the protein.

Temperature, in a medical context, is a measure of the degree of hotness or coldness of a body or environment. It is usually measured using a thermometer and reported in degrees Celsius (°C), degrees Fahrenheit (°F), or kelvin (K). In the human body, normal core temperature ranges from about 36.5-37.5°C (97.7-99.5°F) when measured rectally, and can vary slightly depending on factors such as time of day, physical activity, and menstrual cycle. Elevated body temperature is a common sign of infection or inflammation, while abnormally low body temperature can indicate hypothermia or other medical conditions.

Molecular sequence data refers to the specific arrangement of molecules, most commonly nucleotides in DNA or RNA, or amino acids in proteins, that make up a biological macromolecule. This data is generated through laboratory techniques such as sequencing, and provides information about the exact order of the constituent molecules. This data is crucial in various fields of biology, including genetics, evolution, and molecular biology, allowing for comparisons between different organisms, identification of genetic variations, and studies of gene function and regulation.

I'm sorry for any confusion, but static electricity is not a term that has a specific medical definition. Static electricity is an electrical charge that builds up on the surface of objects. This occurs when there is an imbalance of electric charges within or on the surface of a material. It can be caused by certain conditions, such as friction, which can build up an electric charge.

While not a medical term, static electricity can have various effects in different settings, including medical ones. For instance, it can cause issues with electronic equipment used in healthcare settings. Additionally, some people may experience a shock or spark when they touch a conductive object that has been charged with static electricity. However, these occurrences are not typically considered medical conditions or issues.

I'm sorry for any confusion, but "friction" is not a term that has a specific medical definition. Friction is a physical concept that describes the force that resists the sliding of one surface over another. It is commonly described as the "roughness" between two surfaces. While friction can have effects on various biological processes and medical devices, it does not have a unique medical meaning in and of itself.

Quaternary protein structure refers to the arrangement and interaction of multiple folded protein molecules in a multi-subunit complex. These subunits can be identical or different forms of the same protein or distinctly different proteins that associate to form a functional complex. The quaternary structure is held together by non-covalent interactions, such as hydrogen bonds, ionic bonds, and van der Waals forces. Understanding quaternary structure is crucial for comprehending the function, regulation, and assembly of many protein complexes involved in various cellular processes.

A cell line is a culture of cells that are grown in a laboratory for use in research. These cells are usually taken from a single cell or group of cells, and they are able to divide and grow continuously in the lab. Cell lines can come from many different sources, including animals, plants, and humans. They are often used in scientific research to study cellular processes, disease mechanisms, and to test new drugs or treatments. Some common types of human cell lines include HeLa cells (which come from a cancer patient named Henrietta Lacks), HEK293 cells (which come from embryonic kidney cells), and HUVEC cells (which come from umbilical vein endothelial cells). It is important to note that cell lines are not the same as primary cells, which are cells that are taken directly from a living organism and have not been grown in the lab.

I'm sorry for any confusion, but "thermodynamics" is not a term that has a specific medical definition. It is a branch of physics that deals with the relationships between heat and other forms of energy. However, the principles of thermodynamics can be applied to biological systems, including those in the human body, such as in the study of metabolism or muscle function. But in a medical context, "thermodynamics" would not be a term used independently as a diagnosis, treatment, or any medical condition.

Bacterial proteins are a type of protein that are produced by bacteria as part of their structural or functional components. These proteins can be involved in various cellular processes, such as metabolism, DNA replication, transcription, and translation. They can also play a role in bacterial pathogenesis, helping the bacteria to evade the host's immune system, acquire nutrients, and multiply within the host.

Bacterial proteins can be classified into different categories based on their function, such as:

1. Enzymes: Proteins that catalyze chemical reactions in the bacterial cell.
2. Structural proteins: Proteins that provide structural support and maintain the shape of the bacterial cell.
3. Signaling proteins: Proteins that help bacteria to communicate with each other and coordinate their behavior.
4. Transport proteins: Proteins that facilitate the movement of molecules across the bacterial cell membrane.
5. Toxins: Proteins that are produced by pathogenic bacteria to damage host cells and promote infection.
6. Surface proteins: Proteins that are located on the surface of the bacterial cell and interact with the environment or host cells.

Understanding the structure and function of bacterial proteins is important for developing new antibiotics, vaccines, and other therapeutic strategies to combat bacterial infections.

Tensile strength is a material property that measures the maximum amount of tensile (pulling) stress that a material can withstand before failure, such as breaking or fracturing. It is usually measured in units of force per unit area, such as pounds per square inch (psi) or pascals (Pa). In the context of medical devices or biomaterials, tensile strength may be used to describe the mechanical properties of materials used in implants, surgical tools, or other medical equipment. High tensile strength is often desirable in these applications to ensure that the material can withstand the stresses and forces it will encounter during use.

I'm sorry for any confusion, but "Polystyrenes" is not a medical term. Polystyrene is a type of synthetic aromatic hydrocarbon polymer that is used in a variety of commercial and industrial products, such as packaging materials, insulation, and disposable cutlery. It's important to note that some polystyrene products may contain potentially harmful chemicals, such as styrene, which can leach out into food or drink, posing potential health risks. However, the medical community primarily deals with the health effects of exposure to these chemicals rather than defining the material itself.

Elastomers are a type of polymeric material that exhibit elastic behavior when subjected to deforming forces. They have the ability to return to their original shape and size after being stretched or compressed, making them ideal for use in applications where flexibility, resilience, and durability are required.

Elastomers are composed of long chains of repeating molecular units called monomers, which are cross-linked together to form a three-dimensional network. This cross-linking gives elastomers their unique properties, such as high elasticity, low compression set, and resistance to heat, chemicals, and weathering.

Some common examples of elastomers include natural rubber, silicone rubber, neoprene, nitrile rubber, and polyurethane. These materials are used in a wide range of applications, from automotive parts and medical devices to footwear and clothing.

The actin cytoskeleton is a complex, dynamic network of filamentous (threadlike) proteins that provides structural support and shape to cells, allows for cell movement and division, and plays a role in intracellular transport. Actin filaments are composed of actin monomers that polymerize to form long, thin fibers. These filaments can be organized into different structures, such as stress fibers, which provide tension and support, or lamellipodia and filopodia, which are involved in cell motility. The actin cytoskeleton is constantly remodeling in response to various intracellular and extracellular signals, allowing for changes in cell shape and behavior.

Radiation scattering is a physical process in which radiation particles or waves deviate from their original direction due to interaction with matter. This phenomenon can occur through various mechanisms such as:

1. Elastic Scattering: Also known as Thomson scattering or Rayleigh scattering, it occurs when the energy of the scattered particle or wave remains unchanged after the collision. In the case of electromagnetic radiation (e.g., light), this results in a change of direction without any loss of energy.
2. Inelastic Scattering: This type of scattering involves an exchange of energy between the scattered particle and the target medium, leading to a change in both direction and energy of the scattered particle or wave. An example is Compton scattering, where high-energy photons (e.g., X-rays or gamma rays) interact with charged particles (usually electrons), resulting in a decrease in photon energy and an increase in electron kinetic energy.
3. Coherent Scattering: In this process, the scattered radiation maintains its phase relationship with the incident radiation, leading to constructive and destructive interference patterns. An example is Bragg scattering, which occurs when X-rays interact with a crystal lattice, resulting in diffraction patterns that reveal information about the crystal structure.

In medical contexts, radiation scattering can have both beneficial and harmful effects. For instance, in diagnostic imaging techniques like computed tomography (CT) scans, radiation scattering contributes to image noise and reduces contrast resolution. However, in radiation therapy for cancer treatment, controlled scattering of therapeutic radiation beams can help ensure that the tumor receives a uniform dose while minimizing exposure to healthy tissues.

Phosphatidylcholines (PtdCho) are a type of phospholipids that are essential components of cell membranes in living organisms. They are composed of a hydrophilic head group, which contains a choline moiety, and two hydrophobic fatty acid chains. Phosphatidylcholines are crucial for maintaining the structural integrity and function of cell membranes, and they also serve as important precursors for the synthesis of signaling molecules such as acetylcholine. They can be found in various tissues and biological fluids, including blood, and are abundant in foods such as soybeans, eggs, and meat. Phosphatidylcholines have been studied for their potential health benefits, including their role in maintaining healthy lipid metabolism and reducing the risk of cardiovascular disease.

Skeletal muscle, also known as striated or voluntary muscle, is a type of muscle that is attached to bones by tendons or aponeuroses and functions to produce movements and support the posture of the body. It is composed of long, multinucleated fibers that are arranged in parallel bundles and are characterized by alternating light and dark bands, giving them a striped appearance under a microscope. Skeletal muscle is under voluntary control, meaning that it is consciously activated through signals from the nervous system. It is responsible for activities such as walking, running, jumping, and lifting objects.

Equipment design, in the medical context, refers to the process of creating and developing medical equipment and devices, such as surgical instruments, diagnostic machines, or assistive technologies. This process involves several stages, including:

1. Identifying user needs and requirements
2. Concept development and brainstorming
3. Prototyping and testing
4. Design for manufacturing and assembly
5. Safety and regulatory compliance
6. Verification and validation
7. Training and support

The goal of equipment design is to create safe, effective, and efficient medical devices that meet the needs of healthcare providers and patients while complying with relevant regulations and standards. The design process typically involves a multidisciplinary team of engineers, clinicians, designers, and researchers who work together to develop innovative solutions that improve patient care and outcomes.

In medical terms, 'air' is defined as the mixture of gases that make up the Earth's atmosphere. It primarily consists of nitrogen (78%), oxygen (21%), and small amounts of other gases such as argon, carbon dioxide, and trace amounts of neon, helium, and methane.

Air is essential for human life, as it provides the oxygen that our bodies need to produce energy through respiration. We inhale air into our lungs, where oxygen is absorbed into the bloodstream and transported to cells throughout the body. At the same time, carbon dioxide, a waste product of cellular metabolism, is exhaled out of the body through the lungs and back into the atmosphere.

In addition to its role in respiration, air also plays a critical role in regulating the Earth's climate and weather patterns, as well as serving as a medium for sound waves and other forms of energy transfer.

Protein folding is the process by which a protein molecule naturally folds into its three-dimensional structure, following the synthesis of its amino acid chain. This complex process is determined by the sequence and properties of the amino acids, as well as various environmental factors such as temperature, pH, and the presence of molecular chaperones. The final folded conformation of a protein is crucial for its proper function, as it enables the formation of specific interactions between different parts of the molecule, which in turn define its biological activity. Protein misfolding can lead to various diseases, including neurodegenerative disorders such as Alzheimer's and Parkinson's disease.

In the context of medical terminology, "motion" generally refers to the act or process of moving or changing position. It can also refer to the range of movement of a body part or joint. However, there is no single specific medical definition for the term "motion." The meaning may vary depending on the context in which it is used.

Biosensing techniques refer to the methods and technologies used to detect and measure biological molecules or processes, typically through the use of a physical device or sensor. These techniques often involve the conversion of a biological response into an electrical signal that can be measured and analyzed. Examples of biosensing techniques include electrochemical biosensors, optical biosensors, and piezoelectric biosensors.

Electrochemical biosensors measure the electrical current or potential generated by a biochemical reaction at an electrode surface. This type of biosensor typically consists of a biological recognition element, such as an enzyme or antibody, that is immobilized on the electrode surface and interacts with the target analyte to produce an electrical signal.

Optical biosensors measure changes in light intensity or wavelength that occur when a biochemical reaction takes place. This type of biosensor can be based on various optical principles, such as absorbance, fluorescence, or surface plasmon resonance (SPR).

Piezoelectric biosensors measure changes in mass or frequency that occur when a biomolecule binds to the surface of a piezoelectric crystal. This type of biosensor is based on the principle that piezoelectric materials generate an electrical charge when subjected to mechanical stress, and this charge can be used to detect changes in mass or frequency that are proportional to the amount of biomolecule bound to the surface.

Biosensing techniques have a wide range of applications in fields such as medicine, environmental monitoring, food safety, and biodefense. They can be used to detect and measure a variety of biological molecules, including proteins, nucleic acids, hormones, and small molecules, as well as to monitor biological processes such as cell growth or metabolism.

Proteins are complex, large molecules that play critical roles in the body's functions. They are made up of amino acids, which are organic compounds that are the building blocks of proteins. Proteins are required for the structure, function, and regulation of the body's tissues and organs. They are essential for the growth, repair, and maintenance of body tissues, and they play a crucial role in many biological processes, including metabolism, immune response, and cellular signaling. Proteins can be classified into different types based on their structure and function, such as enzymes, hormones, antibodies, and structural proteins. They are found in various foods, especially animal-derived products like meat, dairy, and eggs, as well as plant-based sources like beans, nuts, and grains.

I believe there might be a misunderstanding in your question. "Glutaral" does not seem to be a recognized medical term or abbreviation in healthcare and biomedical sciences. It is possible that you may be looking for information on "glutaraldehyde," which is a disinfectant and sterilizing agent used in medical settings.

Glutaraldehyde is a chemical compound with the formula C5H8O2, and it's often used as a 2% solution. It's an effective agent against bacteria, viruses, and fungi, making it useful for sterilizing medical equipment. However, glutaraldehyde can cause respiratory issues and skin irritation in some individuals, so proper handling and use are essential to minimize exposure.

If you meant to ask about a different term or if this answer does not address your question, please provide more context or clarify your request, and I will be happy to help further.

In medical terms, "gels" are semi-solid colloidal systems in which a solid phase is dispersed in a liquid medium. They have a viscous consistency and can be described as a cross between a solid and a liquid. The solid particles, called the gel network, absorb and swell with the liquid component, creating a system that has properties of both solids and liquids.

Gels are widely used in medical applications such as wound dressings, drug delivery systems, and tissue engineering due to their unique properties. They can provide a moist environment for wounds to heal, control the release of drugs over time, and mimic the mechanical properties of natural tissues.

Hydrogen-ion concentration, also known as pH, is a measure of the acidity or basicity of a solution. It is defined as the negative logarithm (to the base 10) of the hydrogen ion activity in a solution. The standard unit of measurement is the pH unit. A pH of 7 is neutral, less than 7 is acidic, and greater than 7 is basic.

In medical terms, hydrogen-ion concentration is important for maintaining homeostasis within the body. For example, in the stomach, a high hydrogen-ion concentration (low pH) is necessary for the digestion of food. However, in other parts of the body such as blood, a high hydrogen-ion concentration can be harmful and lead to acidosis. Conversely, a low hydrogen-ion concentration (high pH) in the blood can lead to alkalosis. Both acidosis and alkalosis can have serious consequences on various organ systems if not corrected.

'Staining and labeling' are techniques commonly used in pathology, histology, cytology, and molecular biology to highlight or identify specific components or structures within tissues, cells, or molecules. These methods enable researchers and medical professionals to visualize and analyze the distribution, localization, and interaction of biological entities, contributing to a better understanding of diseases, cellular processes, and potential therapeutic targets.

Medical definitions for 'staining' and 'labeling' are as follows:

1. Staining: A process that involves applying dyes or stains to tissues, cells, or molecules to enhance their contrast and reveal specific structures or components. Stains can be categorized into basic stains (which highlight acidic structures) and acidic stains (which highlight basic structures). Common staining techniques include Hematoxylin and Eosin (H&E), which differentiates cell nuclei from the surrounding cytoplasm and extracellular matrix; special stains, such as PAS (Periodic Acid-Schiff) for carbohydrates or Masson's trichrome for collagen fibers; and immunostains, which use antibodies to target specific proteins.
2. Labeling: A process that involves attaching a detectable marker or tag to a molecule of interest, allowing its identification, quantification, or tracking within a biological system. Labels can be direct, where the marker is directly conjugated to the targeting molecule, or indirect, where an intermediate linker molecule is used to attach the label to the target. Common labeling techniques include fluorescent labels (such as FITC, TRITC, or Alexa Fluor), enzymatic labels (such as horseradish peroxidase or alkaline phosphatase), and radioactive labels (such as ³²P or ¹⁴C). Labeling is often used in conjunction with staining techniques to enhance the specificity and sensitivity of detection.

Together, staining and labeling provide valuable tools for medical research, diagnostics, and therapeutic development, offering insights into cellular and molecular processes that underlie health and disease.

'Escherichia coli' (E. coli) is a type of gram-negative, facultatively anaerobic, rod-shaped bacterium that commonly inhabits the intestinal tract of humans and warm-blooded animals. It is a member of the family Enterobacteriaceae and one of the most well-studied prokaryotic model organisms in molecular biology.

While most E. coli strains are harmless and even beneficial to their hosts, some serotypes can cause various forms of gastrointestinal and extraintestinal illnesses in humans and animals. These pathogenic strains possess virulence factors that enable them to colonize and damage host tissues, leading to diseases such as diarrhea, urinary tract infections, pneumonia, and sepsis.

E. coli is a versatile organism with remarkable genetic diversity, which allows it to adapt to various environmental niches. It can be found in water, soil, food, and various man-made environments, making it an essential indicator of fecal contamination and a common cause of foodborne illnesses. The study of E. coli has contributed significantly to our understanding of fundamental biological processes, including DNA replication, gene regulation, and protein synthesis.

"Immobilized proteins" refer to proteins that have been fixed or attached to a solid support or matrix, such as beads, resins, membranes, or electrodes. This immobilization can be achieved through various methods including physical adsorption, covalent attachment, cross-linking, or entrapment within the matrix.

Immobilized proteins retain their biological activity and can be used in a variety of applications, such as affinity chromatography, biosensors, enzyme catalysis, and drug delivery systems. The immobilization process allows for the repeated use of the protein, increased stability, and easier separation from reaction mixtures. Additionally, the orientation and density of the immobilized proteins can be controlled to optimize their activity and specificity in these applications.

A cell is the basic structural and functional unit of all living organisms, excluding certain viruses. Cells are typically membrane-bound entities that contain genetic material (DNA or RNA), ribosomes, and other organelles that carry out various metabolic functions necessary for the survival and reproduction of the organism.

Cells can vary in size, shape, and complexity depending on the type of organism they belong to. In multicellular organisms, different cells specialize in performing specific functions, leading to a high degree of organization and cooperation within tissues and organs.

There are two main types of cells: prokaryotic cells (such as bacteria) and eukaryotic cells (such as those found in plants, animals, and fungi). Prokaryotic cells are simpler in structure and lack membrane-bound organelles, while eukaryotic cells have a more complex organization and contain various specialized structures enclosed within membranes.

Understanding the properties and behaviors of cells is crucial for understanding life at its most fundamental level and has important implications for fields such as medicine, biotechnology, and agriculture.

Bacterial adhesion is the initial and crucial step in the process of bacterial colonization, where bacteria attach themselves to a surface or tissue. This process involves specific interactions between bacterial adhesins (proteins, fimbriae, or pili) and host receptors (glycoproteins, glycolipids, or extracellular matrix components). The attachment can be either reversible or irreversible, depending on the strength of interaction. Bacterial adhesion is a significant factor in initiating biofilm formation, which can lead to various infectious diseases and medical device-associated infections.

Three-dimensional (3D) imaging in medicine refers to the use of technologies and techniques that generate a 3D representation of internal body structures, organs, or tissues. This is achieved by acquiring and processing data from various imaging modalities such as X-ray computed tomography (CT), magnetic resonance imaging (MRI), ultrasound, or confocal microscopy. The resulting 3D images offer a more detailed visualization of the anatomy and pathology compared to traditional 2D imaging techniques, allowing for improved diagnostic accuracy, surgical planning, and minimally invasive interventions.

In 3D imaging, specialized software is used to reconstruct the acquired data into a volumetric model, which can be manipulated and viewed from different angles and perspectives. This enables healthcare professionals to better understand complex anatomical relationships, detect abnormalities, assess disease progression, and monitor treatment response. Common applications of 3D imaging include neuroimaging, orthopedic surgery planning, cancer staging, dental and maxillofacial reconstruction, and interventional radiology procedures.

I believe there may be some confusion in your question. "Rabbits" is a common name used to refer to the Lagomorpha species, particularly members of the family Leporidae. They are small mammals known for their long ears, strong legs, and quick reproduction.

However, if you're referring to "rabbits" in a medical context, there is a term called "rabbit syndrome," which is a rare movement disorder characterized by repetitive, involuntary movements of the fingers, resembling those of a rabbit chewing. It is also known as "finger-chewing chorea." This condition is usually associated with certain medications, particularly antipsychotics, and typically resolves when the medication is stopped or adjusted.

Calcium is an essential mineral that is vital for various physiological processes in the human body. The medical definition of calcium is as follows:

Calcium (Ca2+) is a crucial cation and the most abundant mineral in the human body, with approximately 99% of it found in bones and teeth. It plays a vital role in maintaining structural integrity, nerve impulse transmission, muscle contraction, hormonal secretion, blood coagulation, and enzyme activation.

Calcium homeostasis is tightly regulated through the interplay of several hormones, including parathyroid hormone (PTH), calcitonin, and vitamin D. Dietary calcium intake, absorption, and excretion are also critical factors in maintaining optimal calcium levels in the body.

Hypocalcemia refers to low serum calcium levels, while hypercalcemia indicates high serum calcium levels. Both conditions can have detrimental effects on various organ systems and require medical intervention to correct.

Fibrillar collagens are a type of collagen that form rope-like fibrils in the extracellular matrix of connective tissues. They are composed of three polypeptide chains, called alpha chains, which are coiled together in a triple helix structure. The most common types of fibrillar collagens are Type I, II, III, V, and XI. These collagens provide strength and support to tissues such as tendons, ligaments, skin, and bones. They also play important roles in the regulation of cell behavior and tissue development. Mutations in genes encoding fibrillar collagens can lead to a variety of connective tissue disorders, including osteogenesis imperfecta, Ehlers-Danlos syndrome, and Marfan syndrome.

Macromolecular substances, also known as macromolecules, are large, complex molecules made up of repeating subunits called monomers. These substances are formed through polymerization, a process in which many small molecules combine to form a larger one. Macromolecular substances can be naturally occurring, such as proteins, DNA, and carbohydrates, or synthetic, such as plastics and synthetic fibers.

In the context of medicine, macromolecular substances are often used in the development of drugs and medical devices. For example, some drugs are designed to bind to specific macromolecules in the body, such as proteins or DNA, in order to alter their function and produce a therapeutic effect. Additionally, macromolecular substances may be used in the creation of medical implants, such as artificial joints and heart valves, due to their strength and durability.

It is important for healthcare professionals to have an understanding of macromolecular substances and how they function in the body, as this knowledge can inform the development and use of medical treatments.

In medical terms, pressure is defined as the force applied per unit area on an object or body surface. It is often measured in millimeters of mercury (mmHg) in clinical settings. For example, blood pressure is the force exerted by circulating blood on the walls of the arteries and is recorded as two numbers: systolic pressure (when the heart beats and pushes blood out) and diastolic pressure (when the heart rests between beats).

Pressure can also refer to the pressure exerted on a wound or incision to help control bleeding, or the pressure inside the skull or spinal canal. High or low pressure in different body systems can indicate various medical conditions and require appropriate treatment.

A laser is not a medical term per se, but a physical concept that has important applications in medicine. The term "LASER" stands for "Light Amplification by Stimulated Emission of Radiation." It refers to a device that produces and amplifies light with specific characteristics, such as monochromaticity (single wavelength), coherence (all waves moving in the same direction), and high intensity.

In medicine, lasers are used for various therapeutic and diagnostic purposes, including surgery, dermatology, ophthalmology, and dentistry. They can be used to cut, coagulate, or vaporize tissues with great precision, minimizing damage to surrounding structures. Additionally, lasers can be used to detect and measure physiological parameters, such as blood flow and oxygen saturation.

It's important to note that while lasers are powerful tools in medicine, they must be used by trained professionals to ensure safe and effective treatment.

An amino acid sequence is the specific order of amino acids in a protein or peptide molecule, formed by the linking of the amino group (-NH2) of one amino acid to the carboxyl group (-COOH) of another amino acid through a peptide bond. The sequence is determined by the genetic code and is unique to each type of protein or peptide. It plays a crucial role in determining the three-dimensional structure and function of proteins.

Titanium is not a medical term, but rather a chemical element (symbol Ti, atomic number 22) that is widely used in the medical field due to its unique properties. Medically, it is often referred to as a biocompatible material used in various medical applications such as:

1. Orthopedic implants: Titanium and its alloys are used for making joint replacements (hips, knees, shoulders), bone plates, screws, and rods due to their high strength-to-weight ratio, excellent corrosion resistance, and biocompatibility.
2. Dental implants: Titanium is also commonly used in dental applications like implants, crowns, and bridges because of its ability to osseointegrate, or fuse directly with bone tissue, providing a stable foundation for replacement teeth.
3. Cardiovascular devices: Titanium alloys are used in the construction of heart valves, pacemakers, and other cardiovascular implants due to their non-magnetic properties, which prevent interference with magnetic resonance imaging (MRI) scans.
4. Medical instruments: Due to its resistance to corrosion and high strength, titanium is used in the manufacturing of various medical instruments such as surgical tools, needles, and catheters.

In summary, Titanium is a chemical element with unique properties that make it an ideal material for various medical applications, including orthopedic and dental implants, cardiovascular devices, and medical instruments.

Rheology is not a term that is specific to medicine, but rather it is a term used in the field of physics to describe the flow and deformation of matter. It specifically refers to the study of how materials flow or deform under various stresses or strains. This concept can be applied to various medical fields such as studying the flow properties of blood (hematology), understanding the movement of tissues and organs during surgical procedures, or analyzing the mechanical behavior of biological materials like bones and cartilages.

Molecular structure, in the context of biochemistry and molecular biology, refers to the arrangement and organization of atoms and chemical bonds within a molecule. It describes the three-dimensional layout of the constituent elements, including their spatial relationships, bond lengths, and angles. Understanding molecular structure is crucial for elucidating the functions and reactivities of biological macromolecules such as proteins, nucleic acids, lipids, and carbohydrates. Various experimental techniques, like X-ray crystallography, nuclear magnetic resonance (NMR) spectroscopy, and cryo-electron microscopy (cryo-EM), are employed to determine molecular structures at atomic resolution, providing valuable insights into their biological roles and potential therapeutic targets.

Silicon compounds refer to chemical substances that contain the element silicon (Si) combined with other elements. Silicon is a Group 14 semimetal in the periodic table, and it often forms compounds through covalent bonding. The most common silicon compound is silicon dioxide (SiO2), also known as silica, which is found in nature as quartz, sand, and other minerals.

Silicon can form compounds with many other elements, including hydrogen, oxygen, halogens, sulfur, nitrogen, and carbon. For example:

* Silanes (SiHn) are a series of silicon-hydrogen compounds where n ranges from 1 to 6.
* Silicones are synthetic polymers made up of alternating silicon and oxygen atoms with organic groups attached to the silicon atoms.
* Silicates are a class of minerals that contain silicon, oxygen, and one or more metal cations. They have a wide range of structures and uses, including as building materials, ceramics, and glass.
* Siloxanes are a group of compounds containing alternating silicon-oxygen bonds with organic groups attached to the silicon atoms.

Silicon compounds have various applications in industry, medicine, and daily life. For instance, silicones are used in medical devices such as breast implants, contact lenses, and catheters due to their biocompatibility and flexibility. Silicates are found in pharmaceuticals, cosmetics, and food additives. Silicon-based materials are also used in dental restorations, bone cement, and drug delivery systems.

Peptides are short chains of amino acid residues linked by covalent bonds, known as peptide bonds. They are formed when two or more amino acids are joined together through a condensation reaction, which results in the elimination of a water molecule and the formation of an amide bond between the carboxyl group of one amino acid and the amino group of another.

Peptides can vary in length from two to about fifty amino acids, and they are often classified based on their size. For example, dipeptides contain two amino acids, tripeptides contain three, and so on. Oligopeptides typically contain up to ten amino acids, while polypeptides can contain dozens or even hundreds of amino acids.

Peptides play many important roles in the body, including serving as hormones, neurotransmitters, enzymes, and antibiotics. They are also used in medical research and therapeutic applications, such as drug delivery and tissue engineering.

Nanospheres are defined in the medical context as tiny, spherical particles that have a diameter in the nanometer range (typically between 1 to 1000 nm). They can be made up of various materials such as polymers, lipids, metals or ceramics. Nanospheres have unique properties due to their small size and large surface area, making them useful for a variety of medical applications including drug delivery, diagnostic imaging, and tissue engineering.

In the field of drug delivery, nanospheres can be used to encapsulate drugs and deliver them to specific sites in the body, improving the efficacy and safety of treatments. They can also be designed to target certain cell types or release their cargo in response to specific stimuli. Additionally, nanospheres can be used as contrast agents for medical imaging techniques such as magnetic resonance imaging (MRI) and computed tomography (CT).

Overall, nanospheres are a promising tool in the development of new medical technologies and therapies.

Molecular Dynamics (MD) simulation is a computational method used in the field of molecular modeling and molecular physics. It involves simulating the motions and interactions of atoms and molecules over time, based on classical mechanics or quantum mechanics. In MD simulations, the equations of motion for each atom are repeatedly solved, allowing researchers to study the dynamic behavior of molecular systems, such as protein folding, ligand-protein binding, and chemical reactions. These simulations provide valuable insights into the structural and functional properties of biological macromolecules at the atomic level, and have become an essential tool in modern drug discovery and development.

Green Fluorescent Protein (GFP) is not a medical term per se, but a scientific term used in the field of molecular biology. GFP is a protein that exhibits bright green fluorescence when exposed to light, particularly blue or ultraviolet light. It was originally discovered in the jellyfish Aequorea victoria.

In medical and biological research, scientists often use recombinant DNA technology to introduce the gene for GFP into other organisms, including bacteria, plants, and animals, including humans. This allows them to track the expression and localization of specific genes or proteins of interest in living cells, tissues, or even whole organisms.

The ability to visualize specific cellular structures or processes in real-time has proven invaluable for a wide range of research areas, from studying the development and function of organs and organ systems to understanding the mechanisms of diseases and the effects of therapeutic interventions.

"Wettability" is not a term that has a specific medical definition. It is a term that is more commonly used in the fields of chemistry, physics, and materials science to describe how well a liquid spreads on a solid surface. In other words, it refers to the ability of a liquid to maintain contact with a solid surface, which can have implications for various medical applications such as the design of medical devices or the study of biological surfaces. However, it is not a term that would typically be used in a clinical medical context.

Hydrophobic interactions: These are the interactions that occur between non-polar molecules or groups of atoms in an aqueous environment, leading to their association or aggregation. The term "hydrophobic" means "water-fearing" and describes the tendency of non-polar substances to repel water. When non-polar molecules or groups are placed in water, they tend to clump together to minimize contact with the polar water molecules. These interactions are primarily driven by the entropy increase of the system as a whole, rather than energy minimization. Hydrophobic interactions play crucial roles in various biological processes, such as protein folding, membrane formation, and molecular self-assembly.

Hydrophilic interactions: These are the interactions that occur between polar molecules or groups of atoms and water molecules. The term "hydrophilic" means "water-loving" and describes the attraction of polar substances to water. When polar molecules or groups are placed in water, they can form hydrogen bonds with the surrounding water molecules, which helps solvate them. Hydrophilic interactions contribute to the stability and functionality of various biological systems, such as protein structure, ion transport across membranes, and enzyme catalysis.

Biocompatible materials are non-toxic and non-reacting substances that can be used in medical devices, tissue engineering, and drug delivery systems without causing harm or adverse reactions to living tissues or organs. These materials are designed to mimic the properties of natural tissues and are able to integrate with biological systems without being rejected by the body's immune system.

Biocompatible materials can be made from a variety of substances, including metals, ceramics, polymers, and composites. The specific properties of these materials, such as their mechanical strength, flexibility, and biodegradability, are carefully selected to meet the requirements of their intended medical application.

Examples of biocompatible materials include titanium used in dental implants and joint replacements, polyethylene used in artificial hips, and hydrogels used in contact lenses and drug delivery systems. The use of biocompatible materials has revolutionized modern medicine by enabling the development of advanced medical technologies that can improve patient outcomes and quality of life.

Rhodobacter is not a medical term, but a genus of bacteria found in the environment. It is commonly found in aquatic environments and can perform photosynthesis, although it is not classified as a plant. Some species of Rhodobacter are capable of fixing nitrogen gas from the atmosphere, making them important contributors to the global nitrogen cycle.

While there may be some medical research into the potential uses or impacts of certain species of Rhodobacter, there is no widely recognized medical definition for this term. If you have any specific concerns about bacteria or infections, it's best to consult with a healthcare professional for accurate information and advice.

Liposomes are artificially prepared, small, spherical vesicles composed of one or more lipid bilayers that enclose an aqueous compartment. They can encapsulate both hydrophilic and hydrophobic drugs, making them useful for drug delivery applications in the medical field. The lipid bilayer structure of liposomes is similar to that of biological membranes, which allows them to merge with and deliver their contents into cells. This property makes liposomes a valuable tool in delivering drugs directly to targeted sites within the body, improving drug efficacy while minimizing side effects.

A buffer in the context of physiology and medicine refers to a substance or system that helps to maintain stable or neutral conditions, particularly in relation to pH levels, within the body or biological fluids.

Buffers are weak acids or bases that can react with strong acids or bases to minimize changes in the pH level. They do this by taking up excess hydrogen ions (H+) when acidity increases or releasing hydrogen ions when alkalinity increases, thereby maintaining a relatively constant pH.

In the human body, some of the key buffer systems include:

1. Bicarbonate buffer system: This is the major buffer in blood and extracellular fluids. It consists of bicarbonate ions (HCO3-) and carbonic acid (H2CO3). When there is an increase in acidity, the bicarbonate ion accepts a hydrogen ion to form carbonic acid, which then dissociates into water and carbon dioxide. The carbon dioxide can be exhaled, helping to remove excess acid from the body.
2. Phosphate buffer system: This is primarily found within cells. It consists of dihydrogen phosphate (H2PO4-) and monohydrogen phosphate (HPO42-) ions. When there is an increase in alkalinity, the dihydrogen phosphate ion donates a hydrogen ion to form monohydrogen phosphate, helping to neutralize the excess base.
3. Protein buffer system: Proteins, particularly histidine-rich proteins, can also act as buffers due to the presence of ionizable groups on their surfaces. These groups can bind or release hydrogen ions in response to changes in pH, thus maintaining a stable environment within cells and organelles.

Maintaining appropriate pH levels is crucial for various biological processes, including enzyme function, cell membrane stability, and overall homeostasis. Buffers play a vital role in preserving these balanced conditions despite internal or external challenges that might disrupt them.

Cell size refers to the volume or spatial dimensions of a cell, which can vary widely depending on the type and function of the cell. In general, eukaryotic cells (cells with a true nucleus) tend to be larger than prokaryotic cells (cells without a true nucleus). The size of a cell is determined by various factors such as genetic makeup, the cell's role in the organism, and its environment.

The study of cell size and its relationship to cell function is an active area of research in biology, with implications for our understanding of cellular processes, evolution, and disease. For example, changes in cell size have been linked to various pathological conditions, including cancer and neurodegenerative disorders. Therefore, measuring and analyzing cell size can provide valuable insights into the health and function of cells and tissues.

I'm sorry for any confusion, but "magnetics" is not a term that is commonly used in medical definitions. It is a term more frequently used in physics and engineering to refer to things related to magnets or magnetic fields. If you have any questions about medical terminology or concepts, I would be happy to try to help with those!

Biomimetic materials are synthetic or natural substances that mimic the chemical, physical, and biological properties of living systems or tissues. These materials are designed to interact with cells, tissues, and organs in ways that resemble the body's own structures and processes. They can be used in a variety of medical applications, including tissue engineering, drug delivery, and medical devices.

Biomimetic materials may be composed of polymers, ceramics, metals, or composites, and they can be designed to have specific properties such as mechanical strength, biocompatibility, and degradability. They may also incorporate bioactive molecules, such as growth factors or drugs, to promote healing or prevent infection.

The goal of using biomimetic materials is to create medical solutions that are more effective, safer, and more compatible with the body than traditional synthetic materials. By mimicking the body's own structures and processes, these materials can help to reduce inflammation, promote tissue regeneration, and improve overall patient outcomes.

The extracellular matrix (ECM) is a complex network of biomolecules that provides structural and biochemical support to cells in tissues and organs. It is composed of various proteins, glycoproteins, and polysaccharides, such as collagens, elastin, fibronectin, laminin, and proteoglycans. The ECM plays crucial roles in maintaining tissue architecture, regulating cell behavior, and facilitating communication between cells. It provides a scaffold for cell attachment, migration, and differentiation, and helps to maintain the structural integrity of tissues by resisting mechanical stresses. Additionally, the ECM contains various growth factors, cytokines, and chemokines that can influence cellular processes such as proliferation, survival, and differentiation. Overall, the extracellular matrix is essential for the normal functioning of tissues and organs, and its dysregulation can contribute to various pathological conditions, including fibrosis, cancer, and degenerative diseases.

Acoustic microscopy is a non-invasive imaging technique that uses sound waves to visualize and analyze the structure and properties of various materials, including biological samples. In the context of medical diagnostics and research, acoustic microscopy can be used to examine tissues, cells, and cellular components with high resolution, providing valuable information about their mechanical and physical properties.

In acoustic microscopy, high-frequency sound waves are focused onto a sample using a transducer. The interaction between the sound waves and the sample generates echoes, which contain information about the sample's internal structure and properties. These echoes are then recorded and processed to create an image of the sample.

Acoustic microscopy offers several advantages over other imaging techniques, such as optical microscopy or electron microscopy. For example, it does not require staining or labeling of samples, which can be time-consuming and potentially damaging. Additionally, acoustic microscopy can provide high-resolution images of samples in their native state, allowing researchers to study the effects of various treatments or interventions on living cells and tissues.

In summary, acoustic microscopy is a non-invasive imaging technique that uses sound waves to visualize and analyze the structure and properties of biological samples with high resolution, providing valuable information for medical diagnostics and research.

Protein denaturation is a process in which the native structure of a protein is altered, leading to loss of its biological activity. This can be caused by various factors such as changes in temperature, pH, or exposure to chemicals or radiation. The three-dimensional shape of a protein is crucial for its function, and denaturation causes the protein to lose this shape, resulting in impaired or complete loss of function. Denaturation is often irreversible and can lead to the aggregation of proteins, which can have negative effects on cellular function and can contribute to diseases such as Alzheimer's and Parkinson's.

Phospholipids are a major class of lipids that consist of a hydrophilic (water-attracting) head and two hydrophobic (water-repelling) tails. The head is composed of a phosphate group, which is often bound to an organic molecule such as choline, ethanolamine, serine or inositol. The tails are made up of two fatty acid chains.

Phospholipids are a key component of cell membranes and play a crucial role in maintaining the structural integrity and function of the cell. They form a lipid bilayer, with the hydrophilic heads facing outwards and the hydrophobic tails facing inwards, creating a barrier that separates the interior of the cell from the outside environment.

Phospholipids are also involved in various cellular processes such as signal transduction, intracellular trafficking, and protein function regulation. Additionally, they serve as emulsifiers in the digestive system, helping to break down fats in the diet.

A plasmid is a small, circular, double-stranded DNA molecule that is separate from the chromosomal DNA of a bacterium or other organism. Plasmids are typically not essential for the survival of the organism, but they can confer beneficial traits such as antibiotic resistance or the ability to degrade certain types of pollutants.

Plasmids are capable of replicating independently of the chromosomal DNA and can be transferred between bacteria through a process called conjugation. They often contain genes that provide resistance to antibiotics, heavy metals, and other environmental stressors. Plasmids have also been engineered for use in molecular biology as cloning vectors, allowing scientists to replicate and manipulate specific DNA sequences.

Plasmids are important tools in genetic engineering and biotechnology because they can be easily manipulated and transferred between organisms. They have been used to produce vaccines, diagnostic tests, and genetically modified organisms (GMOs) for various applications, including agriculture, medicine, and industry.

Cell shape refers to the physical form or configuration of a cell, which is determined by the cytoskeleton (the internal framework of the cell) and the extracellular matrix (the external environment surrounding the cell). The shape of a cell can vary widely depending on its type and function. For example, some cells are spherical, such as red blood cells, while others are elongated or irregularly shaped. Changes in cell shape can be indicative of various physiological or pathological processes, including development, differentiation, migration, and disease.

Membrane proteins are a type of protein that are embedded in the lipid bilayer of biological membranes, such as the plasma membrane of cells or the inner membrane of mitochondria. These proteins play crucial roles in various cellular processes, including:

1. Cell-cell recognition and signaling
2. Transport of molecules across the membrane (selective permeability)
3. Enzymatic reactions at the membrane surface
4. Energy transduction and conversion
5. Mechanosensation and signal transduction

Membrane proteins can be classified into two main categories: integral membrane proteins, which are permanently associated with the lipid bilayer, and peripheral membrane proteins, which are temporarily or loosely attached to the membrane surface. Integral membrane proteins can further be divided into three subcategories based on their topology:

1. Transmembrane proteins, which span the entire width of the lipid bilayer with one or more alpha-helices or beta-barrels.
2. Lipid-anchored proteins, which are covalently attached to lipids in the membrane via a glycosylphosphatidylinositol (GPI) anchor or other lipid modifications.
3. Monotopic proteins, which are partially embedded in the membrane and have one or more domains exposed to either side of the bilayer.

Membrane proteins are essential for maintaining cellular homeostasis and are targets for various therapeutic interventions, including drug development and gene therapy. However, their structural complexity and hydrophobicity make them challenging to study using traditional biochemical methods, requiring specialized techniques such as X-ray crystallography, nuclear magnetic resonance (NMR) spectroscopy, and single-particle cryo-electron microscopy (cryo-EM).

Microspheres are tiny, spherical particles that range in size from 1 to 1000 micrometers in diameter. They are made of biocompatible and biodegradable materials such as polymers, glass, or ceramics. In medical terms, microspheres have various applications, including drug delivery systems, medical imaging, and tissue engineering.

In drug delivery, microspheres can be used to encapsulate drugs and release them slowly over time, improving the efficacy of the treatment while reducing side effects. They can also be used for targeted drug delivery, where the microspheres are designed to accumulate in specific tissues or organs.

In medical imaging, microspheres can be labeled with radioactive isotopes or magnetic materials and used as contrast agents to enhance the visibility of tissues or organs during imaging procedures such as X-ray, CT, MRI, or PET scans.

In tissue engineering, microspheres can serve as a scaffold for cell growth and differentiation, promoting the regeneration of damaged tissues or organs. Overall, microspheres have great potential in various medical applications due to their unique properties and versatility.

Crystallography is a branch of science that deals with the geometric properties, internal arrangement, and formation of crystals. It involves the study of the arrangement of atoms, molecules, or ions in a crystal lattice and the physical properties that result from this arrangement. Crystallographers use techniques such as X-ray diffraction to determine the structure of crystals at the atomic level. This information is important for understanding the properties of various materials and can be used in fields such as materials science, chemistry, and biology.

In the context of medicine and medical devices, calibration refers to the process of checking, adjusting, or confirming the accuracy of a measurement instrument or system. This is typically done by comparing the measurements taken by the device being calibrated to those taken by a reference standard of known accuracy. The goal of calibration is to ensure that the medical device is providing accurate and reliable measurements, which is critical for making proper diagnoses and delivering effective treatment. Regular calibration is an important part of quality assurance and helps to maintain the overall performance and safety of medical devices.

Electroplating is not a medical term, but rather a process used in the industrial field. It refers to the process of coating an electrically conductive object with a thin layer of metal through the use of an electrical current. This process involves immersing the object in a solution containing dissolved ions of the metal to be deposited, and then passing an electric current through the solution. The object serves as the cathode, and the metal ions are reduced at its surface, forming a thin layer of pure metal.

While electroplating is not directly related to medicine, it does have some medical applications. For example, medical devices such as pacemakers or implantable defibrillators may be coated with gold or other metals through electroplating to improve their biocompatibility and reduce the risk of corrosion or rejection by the body. Similarly, dental restorations may be electroplated with precious metals to enhance their strength and durability.

I'm sorry for any confusion, but "Microtechnology" is not a term that has a specific medical definition. Microtechnology generally refers to the development and application of technologies on a microscopic or tiny scale. It is used in various fields including engineering, physics, electronics, and materials science.

In the context of medicine, microtechnologies can be used in the development of medical devices, diagnostic tools, drug delivery systems, and other healthcare applications. For example, microfabrication techniques are used to create microfluidic devices for lab-on-a-chip applications, which can perform complex biochemical analyses for disease diagnosis or drug screening.

However, it's important to note that the application of microtechnologies in medicine is constantly evolving, and new developments and techniques are being explored all the time.

Cytoplasm is the material within a eukaryotic cell (a cell with a true nucleus) that lies between the nuclear membrane and the cell membrane. It is composed of an aqueous solution called cytosol, in which various organelles such as mitochondria, ribosomes, endoplasmic reticulum, Golgi apparatus, lysosomes, and vacuoles are suspended. Cytoplasm also contains a variety of dissolved nutrients, metabolites, ions, and enzymes that are involved in various cellular processes such as metabolism, signaling, and transport. It is where most of the cell's metabolic activities take place, and it plays a crucial role in maintaining the structure and function of the cell.

Circular dichroism (CD) is a technique used in physics and chemistry to study the structure of molecules, particularly large biological molecules such as proteins and nucleic acids. It measures the difference in absorption of left-handed and right-handed circularly polarized light by a sample. This difference in absorption can provide information about the three-dimensional structure of the molecule, including its chirality or "handedness."

In more technical terms, CD is a form of spectroscopy that measures the differential absorption of left and right circularly polarized light as a function of wavelength. The CD signal is measured in units of millidegrees (mdeg) and can be positive or negative, depending on the type of chromophore and its orientation within the molecule.

CD spectra can provide valuable information about the secondary and tertiary structure of proteins, as well as the conformation of nucleic acids. For example, alpha-helical proteins typically exhibit a strong positive band near 190 nm and two negative bands at around 208 nm and 222 nm, while beta-sheet proteins show a strong positive band near 195 nm and two negative bands at around 217 nm and 175 nm.

CD spectroscopy is a powerful tool for studying the structural changes that occur in biological molecules under different conditions, such as temperature, pH, or the presence of ligands or other molecules. It can also be used to monitor the folding and unfolding of proteins, as well as the binding of drugs or other small molecules to their targets.

Hand strength refers to the measure of force or power that an individual can generate using the muscles of the hand and forearm. It is often assessed through various tests, such as grip strength dynamometry, which measures the maximum force exerted by the hand when squeezing a device called a handgrip dynanometer. Hand strength is important for performing daily activities, maintaining independence, and can be indicative of overall health and well-being. Reduced hand strength may be associated with conditions such as neuromuscular disorders, arthritis, or injuries.

In the context of medical and biological sciences, a "binding site" refers to a specific location on a protein, molecule, or cell where another molecule can attach or bind. This binding interaction can lead to various functional changes in the original protein or molecule. The other molecule that binds to the binding site is often referred to as a ligand, which can be a small molecule, ion, or even another protein.

The binding between a ligand and its target binding site can be specific and selective, meaning that only certain ligands can bind to particular binding sites with high affinity. This specificity plays a crucial role in various biological processes, such as signal transduction, enzyme catalysis, or drug action.

In the case of drug development, understanding the location and properties of binding sites on target proteins is essential for designing drugs that can selectively bind to these sites and modulate protein function. This knowledge can help create more effective and safer therapeutic options for various diseases.

Dimerization is a process in which two molecules, usually proteins or similar structures, bind together to form a larger complex. This can occur through various mechanisms, such as the formation of disulfide bonds, hydrogen bonding, or other non-covalent interactions. Dimerization can play important roles in cell signaling, enzyme function, and the regulation of gene expression.

In the context of medical research and therapy, dimerization is often studied in relation to specific proteins that are involved in diseases such as cancer. For example, some drugs have been developed to target and inhibit the dimerization of certain proteins, with the goal of disrupting their function and slowing or stopping the progression of the disease.

Molecular imaging is a type of medical imaging that provides detailed pictures of what is happening at the molecular and cellular level in the body. It involves the use of specialized imaging devices and radiopharmaceuticals (radiotracers) to visualize and measure biological processes, such as gene expression, protein expression, or metabolic activity, within cells and tissues. This information can be used to detect disease at its earliest stages, monitor response to therapy, and guide the development of new treatments.

Molecular imaging techniques include positron emission tomography (PET), single-photon emission computed tomography (SPECT), magnetic resonance imaging (MRI), and computed tomography (CT). These techniques differ in their ability to provide functional, anatomical, or molecular information about the body.

Overall, molecular imaging is a powerful tool for non-invasively visualizing and understanding biological processes at the molecular level, which can lead to improved diagnosis, treatment planning, and patient outcomes.

Microtubules are hollow, cylindrical structures composed of tubulin proteins in the cytoskeleton of eukaryotic cells. They play crucial roles in various cellular processes such as maintaining cell shape, intracellular transport, and cell division (mitosis and meiosis). Microtubules are dynamic, undergoing continuous assembly and disassembly, which allows them to rapidly reorganize in response to cellular needs. They also form part of important cellular structures like centrioles, basal bodies, and cilia/flagella.

... (AFM) or scanning force microscopy (SFM) is a very-high-resolution type of scanning probe microscopy ( ... Atomic force microscopy (AFM) is a type of scanning probe microscopy (SPM), with demonstrated resolution on the order of ... electrostatic forces, magnetic forces (see magnetic force microscope, MFM), Casimir forces, solvation forces, etc. Along with ... The major difference between atomic force microscopy and competing technologies such as optical microscopy and electron ...
Ultrasonic force microscopy, ultrasonic atomic force microscopy, scanning acoustic force microscopy and AFAM all come under the ... Atomic force acoustic microscopy (AFAM) is a type of scanning probe microscopy (SPM). It is a combination of acoustics and ... Scanning tunneling microscopy Ultrasonic force microscopy Scanning near-field ultrasound holography Scanning probe microscopy ... "Acoustic microscopy by atomic force microscopy". Applied Physics Letters. AIP Publishing. 64 (12): 1493-1495. doi:10.1063/ ...
... conductive atomic force microscopy (C-AFM) or current sensing atomic force microscopy (CS-AFM) is a mode in atomic force ... Lanza, Mario (2017). Conductive Atomic Force Microscopy. Berlin, Germany: Wiley-VCH. p. 400. ISBN 978-3-527-34091-0. "PeakForce ... "Spatially resolved electrical measurements of SiO2 gate oxides using atomic force microscopy". Applied Physics Letters. 62 (7 ... conductive scanning probe microscopy (C-SPM) or conductive scanning force microscopy (C-SFM), although CAFM is the most ...
... (bimodal AFM) is an advanced atomic force microscopy technique characterized by generating high ... "Subatomic-scale force vector mapping above a Ge(001) dimer using bimodal atomic force microscopy". Nature Physics. 13 (7): 663- ... Martinez, N. F.; Patil, S.; Lozano, J. R.; Garcia, R. (2006). "Enhanced compositional sensitivity in atomic force microscopy by ... Rodrı́guez, Tomás R.; Garcı́a, Ricardo (2004). "Compositional mapping of surfaces in atomic force microscopy by excitation of ...
... (PC-AFM) is a variant of atomic force microscopy that measures photoconductivity in ... The fundamental principles of photoconductive atomic force microscopy (pc-AFM) are based on those of traditional atomic force ... Until recently, microscopy methods used in the characterization of these OPVs consisted of atomic force microscopy (AFM), ... while scanning tunneling microscopy (STM) and conductive atomic force microscopy (c-AFM) have been used to investigate electron ...
... (nc-AFM), also known as dynamic force microscopy (DFM), is a mode of atomic force ... Giessibl, Franz J. (2000). "Atomic resolution on Si(111)-(7×7) by noncontact atomic force microscopy with a force sensor based ... Giessibl, Franz (1997). "Forces and frequency shifts in atomic-resolution dynamic-force microscopy". Physical Review B. 56 (24 ... of the KolibriSensor to combined atomic-resolution scanning tunneling microscopy and noncontact atomic-force microscopy imaging ...
... chemical force microscopy C-AFM, conductive atomic force microscopy EFM, electrostatic force microscopy KPFM, kelvin probe ... force microscopy MIM, microwave impedance microscopy MFM, magnetic force microscopy PFM, piezoresponse force microscopy PTMS, ... fluidic force microscopy FOSPM, feature-oriented scanning probe microscopy< MRFM, magnetic resonance force microscopy NSOM, ... scanning gate microscopy SQDM, scanning quantum dot microscopy SVM, scanning voltage microscopy FMM, force modulation ...
Atomic force microscopy. High vacuum enables high Q factors on the cantilever oscillation. Scanning tunneling microscopy. High ... Field emission microscopy and Field ion microscopy Atom Probe Tomography (APT) UHV is necessary for these applications to ... Atomic physics experiments which use cold atoms, such as ion trapping or making Bose-Einstein condensates. While not compulsory ... atomic layer deposition (ALD) and UHV pulsed laser deposition (PLD) Angle resolved photoemission spectroscopy (ARPES) ...
Atomic force microscopy (AFM) is an excellent method for obtaining high spatial resolution images of membrane proteins, but it ... Li, G, Y; Xi, N; Wang, D, H (2006). "Probing membrane proteins using atomic force micrsocopy". Journal of Cellular Biochemistry ... Fluorescence-based microscopy (FLM) can be used to study the interactions of membrane proteins in individual cells but it ... SPR microscopy (SPRM) makes possible to simultaneously optical and fluorescence imaging of the same sample, which prove to get ...
Atomic force microscopy is an interaction between a tip attached to a flexible cantilever and the molecule on a cell surface. ... Trache, Andreea; Meininger, Gerald A. (February 2008). "Atomic Force Microscopy (AFM)". Current Protocols in Microbiology. 8 (1 ... Passive methods are methods that sense mechanical forces and do not apply any external forces to the cell. ... The relative deformation of the cell and the tip can be used to estimate how much force was applied and how stiff the cell is. ...
... whereas atomic force microscopy (AFM) and scanning electron microscopy (SEM) are being frequently utilised to observe surface ... Giessibl FJ (2003-07-29). "Advances in atomic force microscopy". Reviews of Modern Physics. 75 (3): 949-983. arXiv:cond-mat/ ... How Atomic Layer Deposition (ALD) works on YouTube Leskelä M, Ritala M (April 2002). "Atomic layer deposition (ALD): from ... "Atomic Layer Deposition Process Development - 10 steps to successfully develop, optimize and characterize ALD recipes - Atomic ...
Atomic force microscopy (AFM), a type of scanning force microscopy, was developed for mapping three-dimensional topographical ... atomic force microscopy uses laser beam deflection to measure the variations in atomic surfaces. The method does not rely on ... Atomic Force Microscopy, NanoScience Instruments. 2011 http://www.nanoscience.com/education/afm.html Balazs, D. J. "Surface ... In these cases, the surface characteristics of the polymer and material, and the resulting forces between them largely ...
In materials science, chemical force microscopy (CFM) is a variation of atomic force microscopy (AFM) which has become a ... Zlatanova, J.; Lindsay, S. M.; Leuba, S. H. (2000). "Single molecule force spectroscopy using the atomic force microscope". ... Noy, A.; Vezenov, D. V.; Lieber, C. M. (1997). "Chemical Force Microscopy". Annu. Rev. Mater. Sci. 27: 381. Bibcode:1997AnRMS.. ... Capillary force is a major problem in tensile force measurements since it effectively strengthens the tip-surface interaction. ...
Klapetek, P.; Valtr, M.; Nečas, D.; Salyk, O.; Dzik, P. (2011). "Atomic force microscopy analysis of nanoparticles in non-ideal ... Frederix, P. L. T. M.; Bosshart, P. D.; Engel, A. (2009). "Atomic Force Microscopy of Biological Membranes". Biophysical ... AFM probes and accessories distributed by NanoAndMore are used for Atomic Force Microscopy in material science, physics, ... cited as a supplier in research papers and is therefore considered an important source of products for Atomic Force Microscopy ...
"Science: Microscope reveals molecules at work". Atomic Force Microscopy in Cell Biology. 2002-05-30. ISBN 9780080549446. "DNA ... In the late 1980s, Hansma then worked on the development of atomic force microscopes and their use in research. This included ... He is also the inventor of Scanning Ion Conductance Microscopy. Hansma is the namesake of the Paul Hansma Research Group at the ... researching the use of probe microscopy and its use in a variety of different fields. As a part of this work, he co-developed ...
For example, high-resolution fluorescence microscopy and atomic force microscopy are both being used to show just how ... Dufrêne, YF (Sep 2008). "Towards nanomicrobiology using atomic force microscopy". Nat Rev Microbiol. 6 (9): 674-80. doi:10.1038 ...
Techniques such as transmission electron microscopy (TEM), scanning electron microscopy (SEM), atomic force microscopy (AFM), ... Polarized Light and Atomic Force Microscopy". Materials. 8 (11): 7873-7888. Bibcode:2015Mate....8.7873G. doi:10.3390/ma8115427 ... When the shearing forces are removed the gel regains much of its original state. The fibrils are isolated from any cellulose ... Chinga-Carrasco, G.; Yu, Y.; Diserud, O. (21 July 2011). "Quantitative Electron Microscopy of Cellulose Nanofibril Structures ...
Atomic force microscopy of nanofiltration membranes: Effect of imaging mode and environment, J. Membr. Sci. 389 (2012) 486-498 ... direct measurement of biological adhesion using an atomic force microscope, J. Membr. Sci. 154(2) (1999) 205-212. Atomic force ... Atomic Force Microscopy and Process Engineering. ISBN 9781856175173. Nutrients and Coloured Compounds in Wastewater. ISBN ... Direct measurement of the force of adhesion of a single biological cell using an atomic force microscope, Colloids and Surfaces ...
1995). "Thermal detection of device failure by atomic force microscopy". IEEE Electron Device Letters. 16 (7): 312-315. Bibcode ... Sub-Ambient Atomic Force Microscopy and Dynamic Mechanical Analysis to the Study of Frozen Aqueous Trehalose Solutions". ... Scanning thermal microscopy (SThM) is a type of scanning probe microscopy that maps the local temperature and thermal ... Majumdar A. Scanning thermal microscopy. Annu. Rev. Mater. Sci. (1999). "Scanning thermal microscopy". Annual Review of ...
Hexa-peri-hexabenzocoronene has been imaged by atomic force microscopy (AFM) providing the first example of a molecule in which ... "Bond-Order Discrimination by Atomic Force Microscopy". Science. 337 (6100): 1326-9. doi:10.1126/science.1225621. PMID 22984067 ...
She evaluated the use of atomic force microscopy and single-molecule force spectroscopy to study the structure of spider ... Atomic force microscopy and single-molecule force spectroscopy". Proceedings of the National Academy of Sciences. 99 (suppl_2 ... "Atomic Force Microscopy of Biomaterials, Mica, and the Origins of Life". Hansma, Helen Greenwood (January 25, 2009). "Could ... "Atomic force microscopy of DNA in aqueous solutions - Nucleic Acids Research - Oxford Academic". Bezanilla, Magdalena; Manne, ...
Kuznetsov YG, Malkin AJ, Lucas RW, Plomp M, McPherson A (September 2001). "Imaging of viruses by atomic force microscopy". The ... The capsid and entire virus structure can be mechanically (physically) probed through atomic force microscopy. In general, ... When infected, a host cell is often forced to rapidly produce thousands of copies of the original virus. When not inside an ... When infected, the host cell is forced to rapidly produce thousands of copies of the original virus. Their life cycle differs ...
... scanning electron microscopy, microprobing, X-ray photoelectron spectroscopy, atomic-force microscopy, and mass spectroscopy.: ... Chernoff; Sherman (2010). "Resurrecting dirty atomic force microscopy calibration standards". Journal of Vacuum Science & ... 270 The effectiveness of carbon dioxide snow cleaning has been demonstrated via light microscopy, particle counting, ...
The recent application of atomic force microscopy, confocal microscopy, Raman spectroscopy, and other sophisticated analytic ... Kempe, A.; Schopf, J. W.; Altermann, W.; Kudryavtsev, A. B.; Heckl, W. M. (2002). "Atomic force microscopy of Precambrian ... Schopf, J. William; Kudryavtsev, Anatoliy B.; Sergeev, Vladimir N. (2010). "Confocal laser scanning microscopy and Raman ...
Recent application of atomic force microscopy, confocal microscopy, Raman spectroscopy, and other analytic techniques to the ... Kempe, A.; Schopf, J. W.; Altermann, W.; Kudryavtsev, A. B.; Heckl, W. M. (2002). "Atomic force microscopy of Precambrian ... The organisms have been better understood as improvements in microscopy facilitated the study of their fine structure, and it ... Schopf, J. William; Kudryavtsev, Anatoliy B.; Sergeev, Vladimir N. (2010). "Confocal laser scanning microscopy and Raman ...
Quate is known for his work on acoustic and atomic force microscopy. The scanning acoustic microscope, invented with a ... Giessibl, Franz J.; Quate, Calvin F. (2006). "Exploring the nanoworld with atomic force microscopy". Physics Today. 59 (12): 44 ... Binnig, Quate and Gerber were rewarded with the Kavli Prize in 2016 for developing the Atomic Force Microscope. Quate was a ... Calvin Forrest Quate (December 7, 1923 - July 6, 2019) was one of the inventors of the atomic force microscope. He was a ...
... for forces. SGMs were developed in the late 1990s from atomic force microscopes. Most importantly, these had to be adapted for ... Scanning gate microscopy (SGM) is a scanning probe microscopy technique with an electrically conductive tip used as a movable ... This is in contrast to other microscopy techniques where the tip is used as a sensor, e.g., ... "On the imaging of electron transport in semiconductor quantum structures by scanning-gate microscopy: successes and limitations ...
This is called Atomic Force Microscopy or AFM. The purpose is to not cause permanent damage to the cell or provoke cellular ... The force plate is arranged to measure the force actually applied to the injection chip (that is, not including the stiffness ... The magnitude of the force is measured using a force plate on a small number of injections to obtain an estimate of the manual ... A manual force is applied to a center fixture of the injection device, moving the lances through cell membranes and into the ...
Humphris, A. D. L.; Miles, M. J.; Hobbs, J. K. (17 January 2005). "A mechanical microscope: High-speed atomic force microscopy ... Atomic Force Microscopy for Biologists(Imperial College Press, 1999). (Microscopes, Scientific techniques). ... D. Sarid, Scanning Force Microscopy, (Oxford Series in Optical and Imaging Sciences, Oxford University Press, New York, 1991). ... This idea was enhanced to create the atomic force microscope (AFM), which is a very high-resolution type of scanning probe ...
... and atomic force microscopy (AFM). The atomic force microscope (AFM) is the defining instrument for the whole field of ... Its AFM probes cover the full range of atomic force microscopy and Scanning probe microscopy applications. NanoWorld AFM probes ... Lee, D.; Lee, H.; Lee, N. S.; Kim, K. B.; Seo, Y. (2012). "High-Speed Atomic Force Microscopy with Phase-detection". Current ... Braunsmann, C.; Schäffer, T. E. (2010). "High-speed atomic force microscopy for large scan sizes using small cantilevers". ...

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