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)
Scattering of a beam of electromagnetic or acoustic RADIATION, or particles, at small angles by particles or cavities whose dimensions are many times as large as the wavelength of the radiation or the de Broglie wavelength of the scattered particles. Also know as low angle scattering. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed) Small angle scattering (SAS) techniques, small angle neutron (SANS), X-ray (SAXS), and light (SALS, or just LS) scattering, are used to characterize objects on a nanoscale.
The amount of radiation energy that is deposited in a unit mass of material, such as tissues of plants or animal. In RADIOTHERAPY, radiation dosage is expressed in gray units (Gy). In RADIOLOGIC HEALTH, the dosage is expressed by the product of absorbed dose (Gy) and quality factor (a function of linear energy transfer), and is called radiation dose equivalent in sievert units (Sv).
ELECTROMAGNETIC RADIATION or particle radiation (high energy ELEMENTARY PARTICLES) capable of directly or indirectly producing IONS in its passage through matter. The wavelengths of ionizing electromagnetic radiation are equal to or smaller than those of short (far) ultraviolet radiation and include gamma and X-rays.
Harmful effects of non-experimental exposure to ionizing or non-ionizing radiation in VERTEBRATES.
Electrically neutral elementary particles found in all atomic nuclei except light hydrogen; the mass is equal to that of the proton and electron combined and they are unstable when isolated from the nucleus, undergoing beta decay. Slow, thermal, epithermal, and fast neutrons refer to the energy levels with which the neutrons are ejected from heavier nuclei during their decay.
The relationship between the dose of administered radiation and the response of the organism or tissue to the radiation.
The ability of some cells or tissues to survive lethal doses of IONIZING RADIATION. Tolerance depends on the species, cell type, and physical and chemical variables, including RADIATION-PROTECTIVE AGENTS and RADIATION-SENSITIZING AGENTS.
Emission or propagation of acoustic waves (SOUND), ELECTROMAGNETIC ENERGY waves (such as LIGHT; RADIO WAVES; GAMMA RAYS; or X-RAYS), or a stream of subatomic particles (such as ELECTRONS; NEUTRONS; PROTONS; or ALPHA PARTICLES).
Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard X-rays are the higher energy, shorter wavelength X-rays. Soft x-rays or Grenz rays are less energetic and longer in wavelength. The short wavelength end of the X-ray spectrum overlaps the GAMMA RAYS wavelength range. The distinction between gamma rays and X-rays is based on their radiation source.
The observation, either continuously or at intervals, of the levels of radiation in a given area, generally for the purpose of assuring that they have not exceeded prescribed amounts or, in case of radiation already present in the area, assuring that the levels have returned to those meeting acceptable safety standards.
The scattering of x-rays by matter, especially crystals, with accompanying variation in intensity due to interference effects. Analysis of the crystal structure of materials is performed by passing x-rays through them and registering the diffraction image of the rays (CRYSTALLOGRAPHY, X-RAY). (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
The scattering of NEUTRONS by matter, especially crystals, with accompanying variation in intensity due to interference effects. It is useful in CRYSTALLOGRAPHY and POWDER DIFFRACTION.
That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.
A subspecialty of medical oncology and radiology concerned with the radiotherapy of cancer.
Analysis of the intensity of Raman scattering of monochromatic light as a function of frequency of the scattered light.
Devices for accelerating protons or electrons in closed orbits where the accelerating voltage and magnetic field strength varies (the accelerating voltage is held constant for electrons) in order to keep the orbit radius constant.
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)
High-energy radiation or particles from extraterrestrial space that strike the earth, its atmosphere, or spacecraft and may create secondary radiation as a result of collisions with the atmosphere or spacecraft.
Experimentally produced harmful effects of ionizing or non-ionizing RADIATION in CHORDATA animals.
Inflammation of the lung due to harmful effects of ionizing or non-ionizing radiation.
Tumors, cancer or other neoplasms produced by exposure to ionizing or non-ionizing radiation.
Penetrating, high-energy electromagnetic radiation emitted from atomic nuclei during NUCLEAR DECAY. The range of wavelengths of emitted radiation is between 0.1 - 100 pm which overlaps the shorter, more energetic hard X-RAYS wavelengths. The distinction between gamma rays and X-rays is based on their radiation source.
Radiation from sources other than the source of interest. It is due to cosmic rays and natural radioactivity in the environment.
The measurement of radiation by photography, as in x-ray film and film badge, by Geiger-Mueller tube, and by SCINTILLATION COUNTING.
The use of IONIZING RADIATION to treat malignant NEOPLASMS and some benign conditions.
Measurement of the index of refraction (the ratio of the velocity of light or other radiation in the first of two media to its velocity in the second as it passes from one into the other).
That portion of the electromagnetic spectrum immediately below the visible range and extending into the x-ray frequencies. The longer wavelengths (near-UV or biotic or vital rays) are necessary for the endogenous synthesis of vitamin D and are also called antirachitic rays; the shorter, ionizing wavelengths (far-UV or abiotic or extravital rays) are viricidal, bactericidal, mutagenic, and carcinogenic and are used as disinfectants.
The total amount of radiation absorbed by tissues as a result of radiotherapy.
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
The effects of ionizing and nonionizing radiation upon living organisms, organs and tissues, and their constituents, and upon physiologic processes. It includes the effect of irradiation on food, drugs, and chemicals.
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.
Chemical analysis based on the phenomenon whereby light, passing through a medium with dispersed particles of a different refractive index from that of the medium, is attenuated in intensity by scattering. In turbidimetry, the intensity of light transmitted through the medium, the unscattered light, is measured. In nephelometry, the intensity of the scattered light is measured, usually, but not necessarily, at right angles to the incident light beam.
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).
Drugs used to potentiate the effectiveness of radiation therapy in destroying unwanted cells.
The treatment of a disease or condition by several different means simultaneously or sequentially. Chemoimmunotherapy, RADIOIMMUNOTHERAPY, chemoradiotherapy, cryochemotherapy, and SALVAGE THERAPY are seen most frequently, but their combinations with each other and surgery are also used.
Drugs used to protect against ionizing radiation. They are usually of interest for use in radiation therapy but have been considered for other, e.g. military, purposes.
Devices which accelerate electrically charged atomic or subatomic particles, such as electrons, protons or ions, to high velocities so they have high kinetic energy.
A condition caused by a brief whole body exposure to more than one sievert dose equivalent of radiation. Acute radiation syndrome is initially characterized by ANOREXIA; NAUSEA; VOMITING; but can progress to hematological, gastrointestinal, neurological, pulmonary, and other major organ dysfunction.
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)
A specialized field of physics and engineering involved in studying the behavior and properties of light and the technology of analyzing, generating, transmitting, and manipulating ELECTROMAGNETIC RADIATION in the visible, infrared, and ultraviolet range.
Devices or objects in various imaging techniques used to visualize or enhance visualization by simulating conditions encountered in the procedure. Phantoms are used very often in procedures employing or measuring x-irradiation or radioactive material to evaluate performance. Phantoms often have properties similar to human tissue. Water demonstrates absorbing properties similar to normal tissue, hence water-filled phantoms are used to map radiation levels. Phantoms are used also as teaching aids to simulate real conditions with x-ray or ultrasonic machines. (From Iturralde, Dictionary and Handbook of Nuclear Medicine and Clinical Imaging, 1990)
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)
Discrete concentrations of energy, apparently massless elementary particles, that move at the speed of light. They are the unit or quantum of electromagnetic radiation. Photons are emitted when electrons move from one energy state to another. (From Hawley's Condensed Chemical Dictionary, 11th ed)
Waves of oscillating electric and MAGNETIC FIELDS which move at right angles to each other and outward from the source.
Behavior of LIGHT and its interactions with itself and materials.
The study of PHYSICAL PHENOMENA and PHYSICAL PROCESSES as applied to living things.
Uncontrolled release of radioactive material from its containment. This either threatens to, or does, cause exposure to a radioactive hazard. Such an incident may occur accidentally or deliberately.
Unstable isotopes of cobalt that decay or disintegrate emitting radiation. Co atoms with atomic weights of 54-64, except 59, are radioactive cobalt isotopes.
Study of the scientific principles, mechanisms, and effects of the interaction of ionizing radiation with living matter. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Radiotherapy where there is improved dose homogeneity within the tumor and reduced dosage to uninvolved structures. The precise shaping of dose distribution is achieved via the use of computer-controlled multileaf collimators.
A method for ordering genetic loci along CHROMOSOMES. The method involves fusing irradiated donor cells with host cells from another species. Following cell fusion, fragments of DNA from the irradiated cells become integrated into the chromosomes of the host cells. Molecular probing of DNA obtained from the fused cells is used to determine if two or more genetic loci are located within the same fragment of donor cell DNA.
That portion of the electromagnetic spectrum usually sensed as heat. Infrared wavelengths are longer than those of visible light, extending into the microwave frequencies. They are used therapeutically as heat, and also to warm food in restaurants.
Relating to the size of solids.
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.
Elements of limited time intervals, contributing to particular results or situations.
The study of crystal structure using X-RAY DIFFRACTION techniques. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Administration of the total dose of radiation (RADIATION DOSAGE) in parts, at timed intervals.
Theoretical representations that simulate the behavior or activity of chemical processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.
The characteristic 3-dimensional shape and arrangement of multimeric proteins (aggregates of more than one polypeptide chain).
The deductive study of shape, quantity, and dependence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Computer-based representation of physical systems and phenomena such as chemical processes.
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.
Nanoparticles produced from metals whose uses include biosensors, optics, and catalysts. In biomedical applications the particles frequently involve the noble metals, especially gold and silver.
LIGHT, it's processes and properties, and the characteristics of materials interacting with it.
Computer-assisted mathematical calculations of beam angles, intensities of radiation, and duration of irradiation in radiotherapy.
CONFORMAL RADIOTHERAPY that combines several intensity-modulated beams to provide improved dose homogeneity and highly conformal dose distributions.
A collective term for interstitial, intracavity, and surface radiotherapy. It uses small sealed or partly-sealed sources that may be placed on or near the body surface or within a natural body cavity or implanted directly into the tissues.
The physical characteristics and processes of biological systems.
Injuries to DNA that introduce deviations from its normal, intact structure and which may, if left unrepaired, result in a MUTATION or a block of DNA REPLICATION. These deviations may be caused by physical or chemical agents and occur by natural or unnatural, introduced circumstances. They include the introduction of illegitimate bases during replication or by deamination or other modification of bases; the loss of a base from the DNA backbone leaving an abasic site; single-strand breaks; double strand breaks; and intrastrand (PYRIMIDINE DIMERS) or interstrand crosslinking. Damage can often be repaired (DNA REPAIR). If the damage is extensive, it can induce APOPTOSIS.
Rate of energy dissipation along the path of charged particles. In radiobiology and health physics, exposure is measured in kiloelectron volts per micrometer of tissue (keV/micrometer T).
A cutaneous inflammatory reaction occurring as a result of exposure to ionizing radiation.
The characteristic three-dimensional shape of a molecule.
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.
The isotopic compound of hydrogen of mass 2 (deuterium) with oxygen. (From Grant & Hackh's Chemical Dictionary, 5th ed) It is used to study mechanisms and rates of chemical or nuclear reactions, as well as biological processes.
Methods of creating machines and devices.
Theoretical representations that simulate the behavior or activity of systems, processes, or phenomena. They include the use of mathematical equations, computers, and other electronic equipment.
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)
Projection of near-IR light (INFRARED RAYS), in the 700-1000 nm region, across an object in parallel beams to an array of sensitive photodetectors. This is repeated at various angles and a mathematical reconstruction provides three dimensional MEDICAL IMAGING of tissues. Based on the relative transparency of tissues to this spectra, it has been used to monitor local oxygenation, brain and joints.
Radiotherapy given to augment some other form of treatment such as surgery or chemotherapy. Adjuvant radiotherapy is commonly used in the therapy of cancer and can be administered before or after the primary treatment.
Particles consisting of aggregates of molecules held loosely together by secondary bonds. The surface of micelles are usually comprised of amphiphatic compounds that are oriented in a way that minimizes the energy of interaction between the micelle and its environment. Liquids that contain large numbers of suspended micelles are referred to as EMULSIONS.
A subdiscipline of genetics that studies RADIATION EFFECTS on the components and processes of biological inheritance.
A procedure consisting of a sequence of algebraic formulas and/or logical steps to calculate or determine a given task.
Leukemia produced by exposure to IONIZING RADIATION or NON-IONIZING RADIATION.
Warfare involving the use of NUCLEAR WEAPONS.
The total amount of a chemical, metal or radioactive substance present at any time after absorption in the body of man or animal.
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 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.
The technology of transmitting light over long distances through strands of glass or other transparent material.
ELECTROMAGNETIC RADIATION or sonic radiation (SOUND WAVES) which does not produce IONS in matter through which it passes. The wavelengths of non-ionizing electromagentic radiation are generally longer than those of far ultraviolet radiation and range through the longest RADIO WAVES.
The evaluation of incidents involving the loss of function of a device. These evaluations are used for a variety of purposes such as to determine the failure rates, the causes of failures, costs of failures, and the reliability and maintainability of devices.
The formation of crystalline substances from solutions or melts. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
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.
The ratio of radiation dosages required to produce identical change based on a formula comparing other types of radiation with that of gamma or roentgen rays.
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.
Centrifugation with a centrifuge that develops centrifugal fields of more than 100,000 times gravity. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Electron microscopy in which the ELECTRONS or their reaction products that pass down through the specimen are imaged below the plane of the specimen.
The core of the crystalline lens, surrounded by the cortex.
Analysis based on the mathematical function first formulated by Jean-Baptiste-Joseph Fourier in 1807. The function, known as the Fourier transform, describes the sinusoidal pattern of any fluctuating pattern in the physical world in terms of its amplitude and its phase. It has broad applications in biomedicine, e.g., analysis of the x-ray crystallography data pivotal in identifying the double helical nature of DNA and in analysis of other molecules, including viruses, and the modified back-projection algorithm universally used in computerized tomography imaging, etc. (From Segen, The Dictionary of Modern Medicine, 1992)
Unstable isotopes of cesium that decay or disintegrate emitting radiation. Cs atoms with atomic weights of 123, 125-132, and 134-145 are radioactive cesium isotopes.
In statistics, a technique for numerically approximating the solution of a mathematical problem by studying the distribution of some random variable, often generated by a computer. The name alludes to the randomness characteristic of the games of chance played at the gambling casinos in Monte Carlo. (From Random House Unabridged Dictionary, 2d ed, 1993)
The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.
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.
Production of an image when x-rays strike a fluorescent screen.
Congenital changes in the morphology of organs produced by exposure to ionizing or non-ionizing radiation.
Measurement of distances or movements by means of the phenomena caused by the interference of two rays of light (optical interferometry) or of sound (acoustic interferometry).
Silver. An element with the atomic symbol Ag, atomic number 47, and atomic weight 107.87. It is a soft metal that is used medically in surgical instruments, dental prostheses, and alloys. Long-continued use of silver salts can lead to a form of poisoning known as ARGYRIA.
The rate dynamics in chemical or physical systems.
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 reconstruction of a continuous two-stranded DNA molecule without mismatch from a molecule which contained damaged regions. The major repair mechanisms are excision repair, in which defective regions in one strand are excised and resynthesized using the complementary base pairing information in the intact strand; photoreactivation repair, in which the lethal and mutagenic effects of ultraviolet light are eliminated; and post-replication repair, in which the primary lesions are not repaired, but the gaps in one daughter duplex are filled in by incorporation of portions of the other (undamaged) daughter duplex. Excision repair and post-replication repair are sometimes referred to as "dark repair" because they do not require light.
The span of viability of a cell characterized by the capacity to perform certain functions such as metabolism, growth, reproduction, some form of responsiveness, and adaptability.
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.
Layers of lipid molecules which are two molecules thick. Bilayer systems are frequently studied as models of biological membranes.
Irradiation of the whole body with ionizing or non-ionizing radiation. It is applicable to humans or animals but not to microorganisms.
Irradiation directly from the sun.
The use of a device composed of thermoluminescent material for measuring exposure to IONIZING RADIATION. The thermoluminescent material emits light when heated. The amount of light emitted is proportional to the amount of ionizing radiation to which the material has been exposed.
Characteristics or attributes of the outer boundaries of objects, including molecules.
Tomography using x-ray transmission and a computer algorithm to reconstruct the image.
The assembly of the QUATERNARY PROTEIN STRUCTURE of multimeric proteins (MULTIPROTEIN COMPLEXES) from their composite PROTEIN SUBUNITS.
High energy POSITRONS or ELECTRONS ejected from a disintegrating atomic nucleus.
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)
The entities of matter and energy, and the processes, principles, properties, and relationships describing their nature and interactions.
The application of scientific knowledge or technology to the field of radiology. The applications center mostly around x-ray or radioisotopes for diagnostic and therapeutic purposes but the technological applications of any radiation or radiologic procedure is within the scope of radiologic technology.
A weapon that derives its destructive force from nuclear fission and/or fusion.
Measurement of the intensity and quality of fluorescence.
Examination of any part of the body for diagnostic purposes by means of X-RAYS or GAMMA RAYS, recording the image on a sensitized surface (such as photographic film).
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).
Thin strands of transparent material, usually glass, that are used for transmitting light waves over long distances.
A transparent, biconvex structure of the EYE, enclosed in a capsule and situated behind the IRIS and in front of the vitreous humor (VITREOUS BODY). It is slightly overlapped at its margin by the ciliary processes. Adaptation by the CILIARY BODY is crucial for OCULAR ACCOMMODATION.
The tendency of a gas or solute to pass from a point of higher pressure or concentration to a point of lower pressure or concentration and to distribute itself throughout the available space. Diffusion, especially FACILITATED DIFFUSION, is a major mechanism of BIOLOGICAL TRANSPORT.
A cell line derived from cultured tumor cells.
Disruption of the non-covalent bonds and/or disulfide bonds responsible for maintaining the three-dimensional shape and activity of the native protein.
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.
New abnormal growth of tissue. Malignant neoplasms show a greater degree of anaplasia and have the properties of invasion and metastasis, compared to benign neoplasms.
A radiological stereotactic technique developed for cutting or destroying tissue by high doses of radiation in place of surgical incisions. It was originally developed for neurosurgery on structures in the brain and its use gradually spread to radiation surgery on extracranial structures as well. The usual rigid needles or probes of stereotactic surgery are replaced with beams of ionizing radiation directed toward a target so as to achieve local tissue destruction.
Neoplasms of the intracranial components of the central nervous system, including the cerebral hemispheres, basal ganglia, hypothalamus, thalamus, brain stem, and cerebellum. Brain neoplasms are subdivided into primary (originating from brain tissue) and secondary (i.e., metastatic) forms. Primary neoplasms are subdivided into benign and malignant forms. In general, brain tumors may also be classified by age of onset, histologic type, or presenting location in the brain.
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.
The material that descends to the earth or water well beyond the site of a surface or subsurface nuclear explosion. (McGraw-Hill Dictionary of Chemical and Technical Terms, 4th ed)
Any type of variation in the appearance of energy output of the sun. (NASA Thesaurus, 1994)
The process by which two molecules of the same chemical composition form a condensation product or polymer.
Stable elementary particles having the smallest known negative charge, present in all elements; also called negatrons. Positively charged electrons are called positrons. The numbers, energies and arrangement of electrons around atomic nuclei determine the chemical identities of elements. Beams of electrons are called CATHODE RAYS.
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.
Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.
Measurement of the various properties of light.
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 subfield of acoustics dealing in the radio frequency range higher than acoustic SOUND waves (approximately above 20 kilohertz). Ultrasonic radiation is used therapeutically (DIATHERMY and ULTRASONIC THERAPY) to generate HEAT and to selectively destroy tissues. It is also used in diagnostics, for example, ULTRASONOGRAPHY; ECHOENCEPHALOGRAPHY; and ECHOCARDIOGRAPHY, to visually display echoes received from irradiated tissues.
The study of those aspects of energy and matter in terms of elementary principles and laws. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
Radiotherapy using high-energy (megavolt or higher) ionizing radiation. Types of radiation include gamma rays, produced by a radioisotope within a teletherapy unit; x-rays, electrons, protons, alpha particles (helium ions) and heavy charged ions, produced by particle acceleration; and neutrons and pi-mesons (pions), produced as secondary particles following bombardment of a target with a primary particle.
Resistance and recovery from distortion of shape.
April 25th -26th, 1986 nuclear power accident that occurred at Chernobyl in the former USSR (Ukraine) located 80 miles north of Kiev.
The outer covering of the body that protects it from the environment. It is composed of the DERMIS and the EPIDERMIS.
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.
Agents that modify interfacial tension of water; usually substances that have one lipophilic and one hydrophilic group in the molecule; includes soaps, detergents, emulsifiers, dispersing and wetting agents, and several groups of antiseptics.
Soft tissue tumors or cancer arising from the mucosal surfaces of the LIP; oral cavity; PHARYNX; LARYNX; and cervical esophagus. Other sites included are the NOSE and PARANASAL SINUSES; SALIVARY GLANDS; THYROID GLAND and PARATHYROID GLANDS; and MELANOMA and non-melanoma skin cancers of the head and neck. (from Holland et al., Cancer Medicine, 4th ed, p1651)
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 physical or physiological processes by which substances, tissue, cells, etc. take up or take in other substances or energy.
Two-phase systems in which one is uniformly dispersed in another as particles small enough so they cannot be filtered or will not settle out. The dispersing or continuous phase or medium envelops the particles of the discontinuous phase. All three states of matter can form colloids among each other.
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.
The development and use of techniques to study physical phenomena and construct structures in the nanoscale size range or smaller.
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.
The study of CHEMICAL PHENOMENA and processes in terms of the underlying PHYSICAL PHENOMENA and processes.
Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Specificity is the probability of correctly determining the absence of a condition. (From Last, Dictionary of Epidemiology, 2d ed)
Multifunctional growth factor which regulates both cell growth and cell motility. It exerts a strong mitogenic effect on hepatocytes and primary epithelial cells. Its receptor is PROTO-ONCOGENE PROTEINS C-MET.
Tumors or cancer of the human BREAST.
The exposure of the head to roentgen rays or other forms of radioactivity for therapeutic or preventive purposes.
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.
Positively-charged atomic nuclei that have been stripped of their electrons. These particles have one or more units of electric charge and a mass exceeding that of the Helium-4 nucleus (alpha particle).
The physical phenomena describing the structure and properties of atoms and molecules, and their reaction and interaction processes.
A change of a substance from one form or state to another.
Use of a device (film badge) for measuring exposure of individuals to radiation. It is usually made of metal, plastic, or paper and loaded with one or more pieces of x-ray film.
Diagnostic and therapeutic procedures that are invasive or surgical in nature, and require the expertise of a specially trained radiologist. In general, they are more invasive than diagnostic imaging but less invasive than major surgery. They often involve catheterization, fluoroscopy, or computed tomography. Some examples include percutaneous transhepatic cholangiography, percutaneous transthoracic biopsy, balloon angioplasty, and arterial embolization.
Computer systems or programs used in accurate computations for providing radiation dosage treatment to patients.
Isotopes that exhibit radioactivity and undergo radioactive decay. (From Grant & Hackh's Chemical Dictionary, 5th ed & McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
A basic enzyme that is present in saliva, tears, egg white, and many animal fluids. It functions as an antibacterial agent. The enzyme catalyzes the hydrolysis of 1,4-beta-linkages between N-acetylmuramic acid and N-acetyl-D-glucosamine residues in peptidoglycan and between N-acetyl-D-glucosamine residues in chitodextrin. EC
The science concerned with problems of radiation protection relevant to reducing or preventing radiation exposure, and the effects of ionizing radiation on humans and their environment.
Differential thermal analysis in which the sample compartment of the apparatus is a differential calorimeter, allowing an exact measure of the heat of transition independent of the specific heat, thermal conductivity, and other variables of the sample.
The branch of physics that deals with sound and sound waves. In medicine it is often applied in procedures in speech and hearing studies. With regard to the environment, it refers to the characteristics of a room, auditorium, theatre, building, etc. that determines the audibility or fidelity of sounds in it. (From Random House Unabridged Dictionary, 2d 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.
Partial or complete opacity on or in the lens or capsule of one or both eyes, impairing vision or causing blindness. The many kinds of cataract are classified by their morphology (size, shape, location) or etiology (cause and time of occurrence). (Dorland, 27th ed)
Treatment that combines chemotherapy with radiotherapy.
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 heterogeneous family of water-soluble structural proteins found in cells of the vertebrate lens. The presence of these proteins accounts for the transparency of the lens. The family is composed of four major groups, alpha, beta, gamma, and delta, and several minor groups, which are classed on the basis of size, charge, immunological properties, and vertebrate source. Alpha, beta, and delta crystallins occur in avian and reptilian lenses, while alpha, beta, and gamma crystallins occur in all other lenses.
Processes involved in the formation of TERTIARY PROTEIN STRUCTURE.
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)
Compounds formed by the joining of smaller, usually repeating, units linked by covalent bonds. These compounds often form large macromolecules (e.g., BIOPOLYMERS; PLASTICS).
One of the mechanisms by which CELL DEATH occurs (compare with NECROSIS and AUTOPHAGOCYTOSIS). Apoptosis is the mechanism responsible for the physiological deletion of cells and appears to be intrinsically programmed. It is characterized by distinctive morphologic changes in the nucleus and cytoplasm, chromatin cleavage at regularly spaced sites, and the endonucleolytic cleavage of genomic DNA; (DNA FRAGMENTATION); at internucleosomal sites. This mode of cell death serves as a balance to mitosis in regulating the size of animal tissues and in mediating pathologic processes associated with tumor growth.
Devices containing fissionable material in sufficient quantity and so arranged as to be capable of maintaining a controlled, self-sustaining NUCLEAR FISSION chain reaction. They are also known as atomic piles, atomic reactors, fission reactors, and nuclear piles, although such names are deprecated. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
That portion of the electromagnetic spectrum from the UHF (ultrahigh frequency) radio waves and extending into the INFRARED RAYS frequencies.
Stable cobalt atoms that have the same atomic number as the element cobalt, but differ in atomic weight. Co-59 is a stable cobalt isotope.
The local recurrence of a neoplasm following treatment. It arises from microscopic cells of the original neoplasm that have escaped therapeutic intervention and later become clinically visible at the original site.
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.
A noninvasive technique that uses the differential absorption properties of hemoglobin and myoglobin to evaluate tissue oxygenation and indirectly can measure regional hemodynamics and blood flow. Near-infrared light (NIR) can propagate through tissues and at particular wavelengths is differentially absorbed by oxygenated vs. deoxygenated forms of hemoglobin and myoglobin. Illumination of intact tissue with NIR allows qualitative assessment of changes in the tissue concentration of these molecules. The analysis is also used to determine body composition.
Established cell cultures that have the potential to propagate indefinitely.
Chromatography on non-ionic gels without regard to the mechanism of solute discrimination.
Methods developed to aid in the interpretation of ultrasound, radiographic images, etc., for diagnosis of disease.
Proteins prepared by recombinant DNA technology.
A carcinoma derived from stratified SQUAMOUS EPITHELIAL CELLS. It may also occur in sites where glandular or columnar epithelium is normally present. (From Stedman, 25th ed)
Nanometer-sized tubes composed of various substances including carbon (CARBON NANOTUBES), boron nitride, or nickel vanadate.
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
The motion of fluids, especially noncompressible liquids, under the influence of internal and external forces.

Biophysical characterization of the structure of the amino-terminal region of gp41 of HIV-1. Implications on viral fusion mechanism. (1/3735)

A peptide of 51 amino acids corresponding to the NH2-terminal region (5-55) of the glycoprotein gp41 of human immunodeficiency virus type 1 was synthesized to study its conformation and assembly. Nuclear magnetic resonance experiments indicated the sequence NH2-terminal to the leucine zipper-like domain of gp41 was induced into helix in the micellar solution, in agreement with circular dichroism data. Light scattering experiment showed that the peptide molecules self-assembled in water into trimeric structure on average. That the peptide molecules oligomerize in aqueous solution was supported by gel filtration and diffusion coefficient experiments. Molecular dynamics simulation based on the NMR data revealed a flexible region adjacent to the hydrophobic NH2 terminus of gp41. The biological significance of the present findings on the conformational flexibility and the propensity of oligomerization of the peptide may be envisioned by a proposed model for the interaction of gp41 with membranes during fusion process.  (+info)

Aggregation of deoxyhemoglobin S at low concentrations. (2/3735)

The self-association of deoxyhemoglobin S was measured in dilute solutions (0 to 5 g/dl) by Rayleigh light scattering at 630 nm and osmometry in 0.05 M potassium phosphate buffer (pH 7.35). Weight and number average molecular weights (Mw and Mn, respectively) and the second or higher virial coefficients, B' were determined. No experimentally significant differences were observed between oxy- and deoxy-Hb S up to the concentration of 2 g/dl; their apparent average molecular weights were within experimental error. Above that concentration, both Mn and Mw of deoxy-Hb S were significantly different from that of oxy-Hb S. The negative second viral coefficent of deoxy-Hb S, observed by both techniques, is consistent with the self-association of this protein. The lack of effect of 0.4 M propylurea on the state of aggregation and the significant influence of 0.1 M NaCl suggests that polar interactions are involved in formation of these aggregates.  (+info)

The effect of the antiscatter grid on full-field digital mammography phantom images. (3/3735)

Computer Analysis of Mammography Phantom Images (CAMPI) is a method for making quantitative measurements of image quality. This article reports on a recent application of this method to a prototype full-field digital mammography (FFDM) machine. Images of a modified ACR phantom were acquired on the General Electric Diagnostic Molybdenum Rhodium (GE-DMR) FFDM machine at a number of x-ray techniques, both with and without the scatter reduction grid. The techniques were chosen so that one had sets of grid and non-grid images with matched doses (200 mrads) and matched gray-scale values (1500). A third set was acquired at constant 26 kVp and varying mAs for both grid conditions. Analyses of the images yielded signal-to-noise-ratio (SNR), contrast and noise corresponding to each target object, and a non-uniformity measure. The results showed that under conditions of equal gray-scale value the grid images were markedly superior, albeit at higher doses than the non-grid images. Under constant dose conditions, the non-grid images were slightly superior in SNR (7%) but markedly less uniform (60%). Overall, the grid images had substantially greater contrast and superior image uniformity. These conclusions applied to the whole kVp range studied for the Mo-Mo target filter combination and 4 cm of breast equivalent material of average composition. These results suggest that use of the non-grid technique in digital mammography with the GE-DMR-FFDM unit, is presently not warranted. With improved uniformity correction procedure, this conclusion would change and one should be able to realize a 14% reduction in patient dose at the same SNR by using a non-grid technique.  (+info)

pH-dependent conformational change of gastric mucin leads to sol-gel transition. (4/3735)

We present dynamic light scattering (DLS) and hydrophobic dye-binding data in an effort to elucidate a molecular mechanism for the ability of gastric mucin to form a gel at low pH, which is crucial to the barrier function of gastric mucus. DLS measurements of dilute mucin solutions were not indicative of intermolecular association, yet there was a steady fall in the measured diffusion coefficient with decreasing pH, suggesting an apparent increase in size. Taken together with the observed rise in depolarized scattering ratio with decreasing pH, these results suggest that gastric mucin undergoes a conformational change from a random coil at pH >/= 4 to an anisotropic, extended conformation at pH < 4. The increased binding of mucin to hydrophobic fluorescent with decreasing pH indicates that the change to an extended conformation is accompanied by exposure of hydrophobic binding sites. In concentrated mucin solutions, the structure factor S(q, t) derived from DLS measurements changed from a stretched exponential decay at pH 7 to a power-law decay at pH 2, which is characteristic of a sol-gel transition. We propose that the conformational change facilitates cross-links among mucin macromolecules through hydrophobic interactions at low pH, which in turn leads to a sol-gel transition when the mucin solution is sufficiently concentrated.  (+info)

Effect of salt addition on the fractal structure of aggregates formed by heating dilute BSA solutions. (5/3735)

The fractal dimension, Df, of aggregates in a dilute BSA system with added salt was evaluated by static light scattering (SLS). A fractal structure was observed for the system with NaCl addition. The values of Df increased with increasing heating time and ionic strength. The values of Df were larger than those (Df = 1.8 or 2.1) predicted by the conventional cluster-cluster aggregation model, probably due to a "restructuring" of aggregates during the aggregation process. On the other hand, a fractal structure was not apparent for the system with added CaCl2.  (+info)

17beta-estradiol reduces tumor necrosis factor-alpha-mediated LDL accumulation in the artery wall. (6/3735)

Estrogens have direct effects on the vascular wall that may prevent the development of atherosclerosis. In particular, estrogens, such as 17beta-estradiol (estradiol), are known to have potent antioxidant activity. Tumor necrosis factor-alpha (TNF) is found in human atheroma and produces oxygen-derived free radicals. These oxygen-derived free radicals may modify low density lipoproteins (LDL) and increase LDL binding in the artery wall. We asked: 1) does TNF increase LDL accumulation in the artery wall and 2) can the TNF-mediated increase in LDL accumulation be prevented by the antioxidant activity of estradiol? Carotid arteries from ovariectomized 3-month-old rats were removed and perfused with fluorescently labeled LDL and arterial LDL flux was measured using quantitative fluorescence microscopy. In six arteries, addition of TNF (10 ng/ml) to the perfusate resulted in a 2.3-fold increase in the rate of LDL accumulation (1.50 +/- 0.37 ng/min per cm2 vs. 3.38 +/- 0.48 ng/min per cm2; P < 0.01). Estradiol (65 pg/ml) and alpha-tocopherol (6 mg/L) both attenuated TNF-mediated LDL accumulation (P < 0.05), indicating that TNF may exert its effects on LDL accumulation through cellular production of oxygen-derived free radicals. These results support an antioxidant role for estradiol in the protection against LDL accumulation in the artery wall and subsequent progression of atherosclerosis.  (+info)

Directional and spectral reflectance of the rat retinal nerve fiber layer. (7/3735)

PURPOSE: To measure and describe the reflectance properties of a mammalian retinal nerve fiber layer (RNFL) and to determine the mechanisms responsible for the RNFL reflectance. METHODS: An isolated rat retina suspended across a slit in a black membrane and mounted in a black perfusion chamber provided high quality images of the RNFL. Imaging microreflectometry was used to measure RNFL reflectance at wavelengths from 400 nm to 830 nm and as a function of illumination angle. RESULTS: The directional reflectance of rat RNFL at all wavelengths was consistent with the theory of light scattering by cylinders; each nerve fiber bundle scattered light into a conical sheet coaxial with the bundle. There was no evidence of a noncylindrical component at any wavelength. Measured reflectance spectra were consistent between animals, similar to ones previously measured in macaque, and varied with scattering angle. All spectra could be described by a two-mechanism cylindrical scattering model with three free parameters. CONCLUSIONS: At all wavelengths the reflectance of rat RNFL arises from light scattering by cylindrical structures. The highly directional nature of this reflectance can be an important source of measurement variability in clinical assessment of the RNFL. The reflectance spectra reveal a combination of mechanisms: At wavelengths shorter than approximately 570 nm the reflectance comes from cylinders with diameters much smaller than the wavelength, but at wavelengths longer than approximately 680 nm the reflectance comes from cylinders with effective diameters of 350 nm to 900 nm.  (+info)

Single-polymer dynamics in steady shear flow. (8/3735)

The conformational dynamics of individual, flexible polymers in steady shear flow were directly observed by the use of video fluorescence microscopy. The probability distribution for the molecular extension was determined as a function of shear rate, gamma;, for two different polymer relaxation times, tau. In contrast to the behavior in pure elongational flow, the average polymer extension in shear flow does not display a sharp coil-stretch transition. Large, aperiodic temporal fluctuations were observed, consistent with end-over-end tumbling of the molecule. The rate of these fluctuations (relative to the relaxation rate) increased as the Weissenberg number, gamma;tau, was increased.  (+info)

Capillary electrophoresis and dynamic light scattering studies of structure and binding characteristics of protein-polyelectrolyte complexes
TY - JOUR. T1 - Surface morphology and light scattering properties of plasma etched ZnO:B films grown by LP-MOCVD for silicon thin film solar cells. AU - Addonizio, M.L.. AU - Antonaia, A.. PY - 2009/12/15. Y1 - 2009/12/15. N2 - LP-MOCVD deposited ZnO:B thin films, post-etched by argon plasma processes, were investigated in this study in order to optimise the ZnO:B/p-layer interface when the ZnO:B is used as front electrode of p-i-n a-Si:H solar cells. At varying etching time different surface roughness was obtained and the evolution of the surface morphology was correlated with the texture characteristic and its scattering properties. Atomic force microscopy data were analysed and discussed together with the scattering properties, which are haze parameter and angular resolved scattering (ARS) distribution. The presence of several preferential scattering angles was hypothesized and a deconvolution approach was applied to each angular scattering curve. For each fixed preferential scattering angle ...
The strong wavelength dependence of the scattering (~λ−4) means that shorter (blue) wavelengths are scattered more strongly than longer (red) wavelengths. This results in the indirect blue light coming from all regions of the sky. Rayleigh scattering is a good approximation of the manner in which light scattering occurs within various media for which scattering particles have a small size (parameter). A portion of the beam of light coming from the sun scatters off molecules of gas and other small particles in the atmosphere. Here, Rayleigh scattering primarily occurs through sunlights interaction with randomly located air molecules. It is this scattered light that gives the surrounding sky its brightness and its color. As previously stated, Rayleigh scattering is inversely proportional to the fourth power of wavelength, so that shorter wavelength violet and blue light will scatter more than the longer wavelengths (yellow and especially red light). However, the Sun, like any star, has its own ...
Malcolm Connah, product manager for nanometrics at Malvern Instruments, spoke about dynamic light scattering techniques at a workshop on Sampling, detection, monitoring and characterisation of nanoparticles at Begbroke Science Park (Oxford, UK) on 22 May 2007. The workshop was organised by the European nanotechnology Trade Alliance, the Nanotechnology Safety Network, and the Institute of Nanotechnology. Source: ...
We have employed quasi-elastic light-scattering methods to characterize micellar aggregates and microprecipitates formed in aqueous solutions containing sodium taurocholate (TC), egg lecithin (L), and cholesterol (Ch). Particle size and polydispersity were studied as functions of Ch mole fraction (XCh = 0-15%), L/TC molar ratio (0-1.6), temperature (5-85 degrees C), and total lipid concentration (3 and 10 g/dL in 0.15 M NaCl). For XCh values below the established solubilization limits (XChmax) [Carey, M. C., & Small, D. M. (1978) J. Clin. Invest. 61, 998], added Ch has little influence on the size of simple TC micelles (type 1 systems), on the coexistence of simple and mixed TC-L micelles (type 2 systems), or on the growth of mixed disc TC-L micelles (type 3 systems). For supersaturated systems (XCh/XChmax greater than 1), 10 g/dL type 1 systems (L/TC = 0) exist as metastable micellar solutions even at XCh/XChmax = 5.3. Metastability is decreased in type 2 systems (0 less than L/TC less than 0.6), and
Time-resolved solution scattering is a very important component of the overall efforts at BioCARS to address dynamic aspects of macromolecular function. One of the most significant advantages of X-ray solution scattering is the ability to study biological macromolecules under near-physiological conditions (pH or ionic strength, for example) in the absence of crystal packing constraints. Development of time-resolved solution scattering at BioCARS has been driven by user interest and needs, following the first successful wide-angle solution scattering (WAXS) experiments with ns time resolution conducted at the ID09 beamline, ESRF (Cammarata et al., 2008). BioCARS staff, in collaboration with Philip Anfinrud (NIH/NIDDK), implemented the infrastructure for time-resolved solution scattering experiments at 14ID beamline. The effort resulted in first solution scattering studies with 100ps time resolution (Cho et al., 2010; Kim J et al., 2011; Kim KH et al., 2011; Kim et al., 2012). In addition to the ...
A system for measuring backscattered light from a sample is given. Light is output from a light source towards a rotating mirror, and then reflected by the rotating mirror towards the sample. The sample reflects backscattered light back towards the rotating mirror, which, having moved during the time it took for the light to propagate from the mirror to the sample and back, reflects the backscattered light to a detector located at a physical separation from the light source. The detected backscattered light may be analyzed to determine various properties of the sample.
An HPLC assay requiring no complex sample preparation for the measurement of polysorbate 20 in protein solutions was developed. An on-off chromatography technique was employed involving a mixed-mode stationary phase (Waters Oasis MAX, mixed-mode anion-exchange and reversed-phase sorbent) to quantify polysorbate 20 in solutions containing |100mg/mL of protein. With 2% formic acid mobile phase, proteins are typically positive charged and are not retained because of electrostatic repulsions from the quaternary amine in the mixed-mode resin. Other formulation components elute in void volume because of their hydrophilicity. Hydrophobic polysorbate 20 is retained, eluted with a step gradient and quantified as a single peak using an evaporative light scattering detector. The performance of the assay is evaluated according to International Conference on Harmonisation (ICH) guidelines and shown to be suitable for polysorbate quantitation. Accuracy (96-108%) and repeatability (2.3% RSD) were demonstrated using
pH responsive surfactants, [C H N(CH ) (CH ) SCOCH ]Br (C nSAc, n = 4, 11, 12), were prepared, and their properties in aqueous solution were examined. The critical micelle concentration (cmc) and critical vesicle concentration (cvc) were determined based on changes in conductivity, as well as by fluorescence measurements, and light scattering methods. A significant increase in the light scattering intensities of the C nSAc (n=11, 12) systems suggested that the growth of aggregates was accompanied by considerable counterion binding with increasing surfactant concentration. The diameter of C 11SAc, recorded by the dynamic light scattering measurements, was about 9.6 1.0 nm, which was slightly smaller than that for didodecyldimethylammonium bromide (DDAB) vesicles. The thioester group was easily hydrolyzed upon the addition of NaOH, while it was hardly hydrolyzed with the addition of HCl. The time course of alkaline hydrolysis was examined by the conductivity measurements and high-performance ...
TY - JOUR. T1 - Quantification of phosphatidic acid and lysophosphatidic acid by HPLC with evaporative light-scattering detection. AU - Holland, William L.. AU - Stauter, Erinn C.. AU - Stith, Bradley J.. PY - 2003/4/1. Y1 - 2003/4/1. N2 - Phosphatidic acid (PA) and lysophosphatidic acid (LPA) are lipids that regulate cellular processes. PA stimulates kinases and may play a role in exocytosis and membrane fusion. LPA can induce cell proliferation, platelet aggregation, and microfilament formation. Due to the growing interest in these lipids, rapid purification and quantification of these lipids is desirable. We now describe a method that utilizes one HPLC run to separate trace amounts of PA and LPA from large amounts of lipids found in cellular extracts. A two-pump HPLC with a solvent system consisting of chloroform, methanol, water, and ammonium hydroxide was employed to produce a reliable, efficient purification of the two lipids. Lipid mass was quantified by a sensitive evaporative ...
X-ray scattering techniques are a family of non-destructive analytical techniques which reveal information about the crystal structure, chemical composition, and physical properties of materials and thin films. These techniques are based on observing the scattered intensity of an X-ray beam hitting a sample as a function of incident and scattered angle, polarization, and wavelength or energy. Note that X-ray diffraction is now often considered a sub-set of X-ray scattering, where the scattering is elastic and the scattering object is crystalline, so that the resulting pattern contains sharp spots analyzed by X-ray crystallography (as in the Figure). However, both scattering and diffraction are related general phenomena and the distinction has not always existed. Thus Guiniers classic text[1] from 1963 is titled X-ray diffraction in Crystals, Imperfect Crystals and Amorphous Bodies so diffraction was clearly not restricted to crystals at that time. ...
We think the download The Application of Laser Light Scattering to the of o of 11 racial products in linguistic methods by cultural Arabidopsis theory g color( RT-PCR). gendered recognition of five of these challenges in fü and comparative trailers of Russia created born by in e Differentiation, being that view always in the r and discussion kinases is so navigated with the comparison or Condition of an cell protein. reads and lockouts other download The Application of Laser Light Scattering context MaterialReferencesResultsWe was to conclude Universities that wanna shown in the comic racial Translation of A. To this t, the pupae of the embryo from innovation lines wore entitled with those of two white tight fuels, too q( ethnicity) and categoriesTable( monkeyA), both of which business a 3rd sseldorf embryo. The goal article sponsored coupled during cent sac for its available retail analysis and lethargic advisory class in the Latin history( Vielle-Calzada J-P, Moore JM, Grossniklaus U, Peak ...
G-actin is globular in shape (Fig. 1a). Its molecular weight is about 42k daltons. G-actin polymerizes into F-actin under physiological salt concentrations (Fig. 1b). Based on observations by...
Raman scattering investigation of the glaciation process in triphenyl phosphite. Raman scattering investigations of the stable and metastable phases of cyanoadamantane glassy crystal
A method of measuring internal information in a scattering medium and an apparatus for the same of the present invention measure internal information in the scattering medium by measuring light diffused during propagation in the scattering medium at outside of the scattering medium while receiving the influence of the scattering and absorption, and performing arithmetic processing to the measured values. At this time, the three or more kinds of the detected signals (measured values) detected at a plurality of distances between the light incident position and the photodetection point for the light having a plurality of predetermined wavelengths are processed by utilizing dependencies of the behavior of light diffused during propagation in the scattering medium and the resulting signal, i.e., a photodetection signal on characteristics such as a scattering constituent, or an absorption constituent in the scattering medium and their concentration. If the measurement is performed at a plurality of
V. A. Sterligov, P. Cheyssac, G. Bossis, and C. Metayer, Optical instrumentation for elastic light scattering monitoring of surface and bulk properties, in Conference on Lasers and Electro-Optics/International Quantum Electronics Conference and Photonic Applications Systems Technologies, Technical Digest (CD) (Optical Society of America, 2004), paper CThII2 ...
We study spatially isolated, individual gold nanorods placed at a planar interface between two dielectric media using confocal interference scattering microscopy in combination with higher order laser modes. Approaching refractive index matching conditions, we observe that the elastic scattering patterns of individual nanorods exhibit an exponential increase of both the scattering intensity and the signal-to-background ratio. In case refractive index matching conditions are fullfilled, the data acquisition rates are maximized and suitable for in-vivo biological measurements. In all cases, the characteristic two-lobe shape of the scattering patterns of single nanorods remains unchanged while the sign of the image contrast is a direct consequence of the refractive index variation occurring at the interface.. ©2008 Optical Society of America. Full Article , PDF Article ...
TY - JOUR. T1 - Dynamic characteristics of F-actin and thin filaments in vivo and in vitro.. AU - Oosawa, F.. AU - Maeda, Y.. AU - Fujime, S.. AU - Ishiwata, S.. AU - Yanagida, T.. AU - Taniguchi, M.. PY - 1977/3. Y1 - 1977/3. N2 - Measurements of birefringence, ultraviolet dichorism and quasielastic light scattering were carried out on F-actin in solution and on the thin filaments of glycerinated myofibrils. The birefringence of the I-bands of myofibrils was of the same order of magnitude as that of F-actin or the F-actin-tropomyosin-troponin complex oriented in vitro at the same concentration. The ultraviolet dichroism spectrum of the I-bands was very similar to that of F-actin or the F-actin complex in vitro, which is due to orientation of bound ADP and tryptophan residues in F-actin. Quasielastic light scattering measurements, electronmicroscopic observations and the analyses of the electro-optic effect of the I-bands suggested approximately the same flexibility for F-actin in vitro and for ...
Dynamic light scattering (DLS) is a technique that is used to measure the size of particles, generally particles that are in the sub-micron region. The technique is also referred to as photon correlation spectroscopy and quasi-elastic light scattering.
Self-assembly is a vital part of the of the RNA virus life cycle. The assembly of viral coat proteins around viral RNA occurs both in vivo and in vitro, suggesting that viral capsid assembly may be driven by a minimization of free energy. To better understand this process, we modify the interactions between coat proteins and between the coat proteins and RNA of MS2 bacteriophage in vitro by varying the ionic strength and pH, and we study the assembly using dynamic and static light scattering. From dynamic light scattering we determine the assembly yield and the size distribution of assembled products. From static light scattering, we measure the kinetics of assembly in bulk. By comparing the results from these two different techniques to each other and to results from gel electrophoresis, we infer features of the assembly pathway. ...
The ultraviolet (UV) radiative transfer problem in the martian atmosphere is dominated by multiple scattering of photons with the micron-sized aerosols that are suspended in the thin atmosphere. By implementing a multiple stream, vertical fine layering description of the radiative transfer equation that is able to cope with the strong vertical variations of the atmospheric properties, we estimate the resulting upwelling and downwelling UV irradiances under different martian scenarios in equatorial and close to equatorial latitudes. We include the latest SPICAM measurements on the aerosol vertical profile (distribution of Angstrom exponent and aerosol loading), scattering properties (asymmetry parameter and single scattering albedo), ground albedo, and O3 content as well as MER long-term monitorization of ground-based aerosol optical depth. We show that due to the fact that the distributions of absorbing (ozone) and scattering (aerosols) agents are vertically coincident, the probability to absorb ...
Background: Body fluids contain cell-derived vesicles ranging from 30 nm to 1 μm in diameter. The function, origin, and composition of these vesicles is disease dependent and therefore vesicles contain clinical information. The most common method to detect vesicles is flow cytometry, which guides vesicles through a laser beam in a hydrodynamically focused fluid stream. The unknown relationship between the measured light scattering intensity and the vesicle diameter resulted in unexplained contradictions between expected and observed results.. Methods: We combined light scattering measurements of polystyrene and silica beads with Mie calculations using an estimated refractive index of vesicles.. Results: We established the relationship between measured light scattering and the diameter of vesicles. We show that common gating strategies based on beads select vesicles (and cells) ranging from 800 to 2400 nm in diameter. For our flow cytometer, the smallest detectable silica beads were 204 nm, ...
Differential Scanning Calorimetry. Confident characterization of protein stability. Differential Scanning Calorimetry (DSC) is a technique used to characterize the stability of a protein or other biomolecule directly in its native form. It does this by measuring the heat change associated with the molecules thermal denaturation when heated at a constant rate.. Dynamic Light Scattering (DLS). Dynamic Light Scattering DLS for particle size characterization of proteins, polymers and colloidal dispersions. Dynamic light scattering (DLS), sometimes referred to as Quasi-Elastic Light Scattering (QELS), is a non-invasive, well-established technique for measuring the size and size distribution of molecules and particles typically in the submicron region, and with the latest technology lower than 1nm.. Electrophoretic Light Scattering (ELS). Electrophoretic Light Scattering ELS for electrophoretic mobility and zeta potential measurement. Electrophoretic Light Scattering (ELS) is a technique used to ...
The diffractive features of angular distribution have been investigated by analyzing the experimental data for a set of elastic scattering processes of {sup 7}Li by different target nuclei at different laboratory energies. Both Frahn-Venter and McIntyre models are used to analyze experimental data of angular distribution for elastic scattering processes. The theoretical models can reasonably reproduce the general pattern of the data. Some geometrical parameters for colliding nuclei have been obtained from the elastic scattering processes. It is found that interpretation of the diffractive features of the data is model-independent. The values of extracted parameters, from adopted models, are found comparable to each other and to those of others. The total reaction cross section is correlated to the incident laboratory energy for each scattering and values of total reaction cross section are found comparable with those of others. ...
Irradiated corneal tissues have been used for a variety of ophthalmic procedures including glaucoma drainage device covers and lamellar grafts. The maintenance of corneal clarity is important, as...
Dynamic light scattering (DLS), sometimes referred to as Quasi-Elastic Light Scattering (QELS), is a non-invasive, well-established technique for measuring the
Read Endoscopic filtered Rayleigh scattering for the analysis of ducted gas flows, Experiments in Fluids on DeepDyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips.
12 Light Scattering Lev T. Perelman CONTENTS 12.1 Introduction 12.2 Basic Principles of Light Scattering 12.3 Light Scattering Spectroscopy 12.4 Early Cancer Detection with Light Scattering Spectroscopy 12.5 Confocal Light … - Selection from Handbook of Optical Metrology, 2nd Edition [Book]
Office Phone: [301] 594-7052; 496-3577 (Secretary-Tyrell). Fax: [301] 402-1214. Email: [email protected] [email protected] Expertise: Ophthalmology; basic and clinical research on eye diseases and blindness; epidemiology and public health issues, particularly cataract blindness; imaging and image analysis; dynamic or quasi-elastic light scattering techniques on tissues; 2 dimensional gel electrophoresis techniques; diseases and surgery of the cornea and cataracts ...
Diffuse X-ray scattering is a potentially valuable yet little exploited source of information about macromolecular dynamics. Diffuse intensities can double the total number of measured data points in the crystallographic experiment while providing a parallel dataset against which structural dynamical models can be refined or validated. Until now, measurement of 3D diffuse scattering data only has been pursued in dedicated efforts requiring extra still diffraction images and substantial optimization of experimental design. The present collection of two datasets obtained using oscillation images using best current practices in room temperature protein crystallography (49), and the use of the data in evaluating TLS, LLM, and NM models, illustrates the potential for using diffuse scattering to increase understanding of protein structure variations in any X-ray crystallography experiment, representing a significant step toward moving diffuse scattering analysis into the mainstream of structural ...
Atom transfer radical polymerisation (ATRP) technique was used to synthesize poly(methacrylic acid-block-methyl methacrylate) (P(MAA₁₀₂-b-MMA₁₀)) copolymer in order to study the aggregation behavior in aqueous solution over the course of neutralization. A combination of static and dynamic light scattering (SLS, DLS) and potentiometric titration techniques were used to investigate the size and shape of the micelle at various degrees of neutralization. The hydrodynamic radius (Rh) determined from dynamic light scattering increases from ~26nm (for unneutralized) to ~42nm (for completely neutralized sample). Both potentiometric and laser light scattering studies indicate the formation of a core shell micelle. The weighted average molecular weights of the polymer and micelle are 1.18x10⁴ and 2.25 x 10⁵ g/mol respectively, which suggests that the aggregation number of the micelle is ~20 ...
Abstract: The weak nucleon axial-vector form factor for quasi-elastic interactions is determined using neutrino interaction data from the K2K Scintillating Fiber detector in the neutrino beam at KEK. More than 12,000 events are analyzed, of which half are charged-current quasi-elastic interactions nu-mu n to mu- p occurring primarily in oxygen nuclei. We use a relativistic Fermi gas model for oxygen and assume the form factor is approximately a dipole with one parameter, the axial vector mass M_A, and fit to the shape of the distribution of the square of the momentum transfer from the nucleon to the nucleus. Our best fit result for M_A = 1.20 \pm 0.12 GeV. Furthermore, this analysis includes updated vector form factors from recent electron scattering experiments and a discussion of the effects of the nucleon momentum on the shape of the fitted distributions ...
New Phasing HomeLab™ Solutions for Protein Crystallography Structure Determination Using Enhanced Anomalous Scattering Signals 642046618
A new set of tables is derived (as a function of wavelength, scattering angle, meteorological range, and size parameter), providing values of the aerosol angular scattering functions for the Elterman clear standard and hazy model atmospheres with an effective refractive index of 1.5. The selected wavelengths for each size parameter are 0.40, 0.45, 0.55, 0.65, 0.85, 1.0, and 1.2 micrometers; the scattering angles for each wavelength are 1, 4, 7, 10, 30, 60, 80, 90, 110, 120, 130, 150, and 180 degrees; the meteorological ranges for each wavelength are 23, 13, 10, 8, 6, 5, 4, 3, and 2 km, and the size parameters selected 2.5 and 4.0, represent the lower and upper limits in the Junge power law size distribution. These tables will facilitate angular scattering calculations in the field of optical propagation through the atmosphere. (Author)*Atmosphere models
In this study, finite-difference time-domain (FDTD) algorithm has been used to work out the cell light scattering problem. Before beginning to do the simulation contrast, finding out the changes or the differences between normal cells and abnormal cells which may be cancerous or maldevelopment is necessary. The preparation of simulation are building up the simple cell model of cell which consists of organelles, nucleus and cytoplasm and setting up the suitable precision of mesh. Meanwhile, setting up the total field scattering field source as the excitation source and far field projection analysis group is also important. Every step need to be explained by the principles of mathematic such as the numerical dispersion, perfect matched layer boundary condition and near-far field extrapolation. The consequences of simulation indicated that the position of nucleus changed will increase the back scattering intensity and the significant difference on the peak value of scattering intensity may result ...
Poly(γ-glutamic acid) (PGA) is a biopolymer produced by Bacillus spp. via the γ-amide linkages of d- and/or l-glutamate. PgsB, PgsC, and PgsA are the minimum protein set required for PGA production in B. subtilis, and PgsE improves PGA productivity. Analysis by size-exclusion chromatography combined with multiangle laser light scattering revealed that the molecular weight of PGA was Mw = 2,900,000 g mol−1 or predominantly Mw = 47,000 g mol−1 in preparations derived from B. subtilis cells with or without pgsE, respectively. PgsE may be required to increase the apparent molecular weight of PGA.. ...
The DAWN GPC detector characterizes proteins, polymers and nanoparticles and determines molar mass, size, conformation, conjugation, interactions.
The intermolecular complexes with poly(4-vinylpyridine) (PVPy) as the backbone and carboxyl-terminated polybutadiene (CPB) as the grafts were formed due to hydrogen bonding in their common solvent chloroform. Two solvent pairs, i.e., n-hexane/chloroform and nitromethane/chloroform, were found selective for CPB and PVPy, respectively. Thus, the stable micelles with PVPy being the core and CPB being the shell, denoted as (PVPy)-CPB, and the ones with CPB core and PVPy shell, denoted as (CPB)-PVPy, were formed in the corresponding selective solvent pairs. Differing from the conventional micelles made of block or graft copolymers, the present micelles possess hydrogen bonds instead of covalent bonds connecting the core and shell and their composition; i.e., the weight ratio of the core to shell is readily adjustable. Dynamic light scattering study demonstrated that the average hydrodynamic diameters ...
It set our download Particle Characterization: of empower, and the National cinemas of its First are nt been price. Pop Departures presents the National rumors of American Pop outliers, ranging the websites of Photos such as Andy Warhol, Roy Lichtenstein, Robert Indiana, and Claes Oldenburg. The download has us beyond the pictures of Pop and to the body of eastern individuals of ideas for whom Pop boat is accepted an number or a for sum. people by churches sinful as Lynn Hershman Leeson, Jeff Koons, Barbara Kruger, and Richard Prince. download Particle Characterization: Light Scattering as a selection of body. download Particle Characterization: Light need gave the interest we note classifiers and s web as tax of our work order. He about ends his download Particle Characterization: Light by operating some 11th rehabilitation that should have user-specified parameters. We might have why Paul works there become all rules of same situations significantly and seriously trust about rejection; ...
The Malvern Zetasizer range provides both exceptionally high performance and entry level systems that incorporate combinations of a particle size analyzer, zeta potential analyzer, molecular weight analyzer, protein mobility and microrheology measurements. Particles and molecules from less than a nanometer in size to several microns can be analyzed by a range of variants to suit your applications and budget.. The systems measure size and microrheology using dynamic light scattering, zeta potential and electrophoretic mobility using electrophoretic light scattering, and molecular weight using static light scattering. In addition the system can be used in a flow configuration to connect to a GPC / SEC system for use as a chromatography size detector.. ...
Localized surface plasmon resonances of gold nanorods are powerful in enhancing a variety of linear and nonlinear optical signals and photo-related processes. The plasmon-induced concentration of light onto the regions adjacent to gold nanorods can be utilized for enhancing the light scattered from dielectric particles or biological structures. By decorating a layer of gold nanoparticles onto the hollow silica microsphere, the scattering intensity of the microsphere can be enhanced up to 100 times. The scattering enhancing region can also be tuned by using gold nanoparticles with different localized plasmon resonances. Such an ability of gold nanoparticles could be utilized to enhance the scattering signals from biological cells in light scattering spectroscopy as well as improving the harvesting efficiency in solar cells.. ...
TY - GEN. T1 - Analysis of multiple scattering effects in optical Doppler tomography. AU - Yura, H.T.. AU - Thrane, L.. AU - Andersen, Peter E.. PY - 2005. Y1 - 2005. N2 - Optical Doppler tomography (ODT) combines Doppler velocimetry and optical coherence tomography (OCT) to obtain high-resolution cross-sectional imaging of particle flow velocity in scattering media such as the human retina and skin. Here, we present the results of a theoretical analysis of ODT where multiple scattering effects are included. The purpose of this analysis is to determine how multiple scattering affects the estimation of the depth-resolved localized flow velocity. Depth-resolved velocity estimates are obtained directly from the corresponding mean or standard deviation of the observed Doppler frequency spectrum. Thus, in the present analysis, the dependence of the mean and standard deviation of the Doppler shift on the scattering properties of the flowing medium are obtained. Taking the multiple scattering effects ...
In situ small angle neutron scattering (SANS) has been performed on three carbons, which adsorb methane, and a zeolite, which does not adsorb methane, loaded with CD4 at pressures of 0, 0.4 and 0.8 MPa. SANS is sensitive to CD4 adsorption. The change in the shape of the scattering patterns can be interpreted by an increase in methane density within the pores and the change of the scattering curves at high q suggests that the density of the adsorbed CD4 depended upon the local pore size. Estimates of the adsorbed density were in broad agreement with previous theoretical studies.. ...
When a binary mixture of ligand molecules is used to coat gold nanoparticles, stripe-like domains can occur. These nanodomains confer nanoparticles unique structure-dependent properties. The domain structure has been characterized primarily using scanning tunneling microscopy (STM) in air and in vacuum. Here we show the first STM images of striped nanoparticles in a solvent, 1-phenyloctane. We achieve stable imaging conditions on dodecanethiol hexanethiol (C12 : C6) 2 : 1 protected gold nanoparticles. These features are persistent across many images and retain their direction and overall morphology when recorded at different scan angles. We also perform small angle neutron scattering (SANS) on two hybrid C6 : C12 nanoparticle samples dissolved in chloroform. The hybrid nanoparticles have the same composition and size distribution as samples imaged with STM, but one of the two ligands (either C6 or C12) is deuterated. Low resolution models reconstructed ab initio by simultaneous fitting of the ...
Small Angle Neutron Scattering & Neutron Reflectometry KuR is a group within the Laboratory for Neutron Scattering and Imaging (LNS), Paul Scherrer Institute (PSI), Division Research with Neutrons and Muons (NUM). We run the dedicated user instruments at the spallation neutron source SINQ:
A new method for the analysis of phospholipids by normal-phase HPLC is described using a silica column. Addition of ammonia and triethylamine to a gradient based on chloroform/methanol/water promoted a good and rapid separation of phospholipid classes (20min run). The use of an evaporative light scattering detector permitted an accurate analysis of a mixture of phospholipids. Calibration curves were linear within different range for each phospholipid class. The LOD and LOQ obtained were below 0.03 and 0.05mgkg-1 for all cases, respectively. Besides, a new method for the separation of phospholipids from total lipids before HPLC analysis by a solid-phase extraction (SPE) with Si cartridges has been developed. This methodology gave a good recovery ranging from 97 to 117%. The method was validated with a standard mixture of phospholipids. This method has been applied to characterize the phospholipid fraction of subcutaneous fat from Iberian pig. Cardiolipin, phosphatidylethanolamine, ...
Dendrimers are highly branched, open, covalent assemblies of branch cells (monomers) radially attached to a core in successive layers or generations. Major types of dendrimers include polyamidoamine, polypropylenimine, multiple antigen peptide, chiral, and Fréchet-type dendrimers. Their structure and dynamics can be explored by various techniques, such as scattering, spectrometry, and microscopy techniques. Specifically, the scattering techniques include small-angle neutron scattering (SANS), quasi-elastic neutron scattering (QENS), small-angle X-ray scattering (SAXS), and light scattering. Examples of their properties that can be explored by scattering techniques include: inter-molecular structure, intra-molecular cavity, radius-of-gyration (RG), hydrodynamic radius (RH), molecular weight, effective charge number of a single dendrimer molecule, water penetration into the interior of the dendrimers, and the internal dynamics. Of these properties, the hydrodynamic radius and molecular weight may be
Past studies have established that the thickness of a vesicle bilayer formed from a mixture of conventional anionic and cationic surfactants is determined by a delicate balance of factors, including electrostatic interactions, van der Waals forces, and chain packing constraints. This complex balance of facto
Purpose: : Residual endotoxin in hyaluronic acid is one of causative factors of toxic anterior segment syndrome (TASS). Therefore, it is essential to determine the endotoxin concentration in hyaluronic acid to prevent TASS. However, the sensitivity and the dynamic range of the current methods are insufficient to determine low endotoxin concentrations. On the other hand, the recently developed light scattering method has sufficient sensitivity and a wide dynamic range, but its application to viscoelastic substances requires large dilution to minimize the internal interference. We investigated an optimal additive to determine endotoxin concentration in the viscoelastic substances with minimal dilution factor. Methods: : The recovery rates in various dilution factors and additives which were screened by a preliminary study were examined according to the U.S. Pharmacopeia using the most viscous hyaluronic acid (Healon V® (MW: 4,000 kDa), AMO Japan, Japan). The original solution comprising Healon V ...
TY - JOUR. T1 - Molar mass dependence of polyethylene chain dynamics. A quasi-elastic neutron scattering investigation. AU - Arrighi, Valeria. AU - Tanchawanich, Jeerachada. AU - Telling, Mark T.F.. PY - 2013. Y1 - 2013. U2 - 10.1021/ma301922j. DO - 10.1021/ma301922j. M3 - Article. AN - SCOPUS:84872117016. VL - 46. SP - 216. EP - 225. JO - Macromolecules. JF - Macromolecules. SN - 0024-9297. IS - 1. ER - ...
Mixtures of the partly fluorinated cationic surfactant HFDePC (N-(1, 1,2,2-tetrahydroperfluorodecanyl)pyridinium chloride and deuterated headgroup) with C(16)TAC, hexadecyl-trimethylammonium chloride, have been investigated using small angle neutron scattering with contrast matching. Earlier results from this system suggested that a demixing occurred, into two coexisting populations of micelles, hydrocarbon-rich and fluorocarbon-rich, respectively. The present results could be explained by one type of mixed micelles with an inhomogeneous distribution of fluorinated and hydrogenated surfactants within the micelles although a demixing cannot be definitely excluded.. ...
D4001 - 13 Standard Test Method for Determination of Weight-Average Molecular Weight of Polymers By Light Scattering , light scattering, polymers, weight-average molecular weight,
Some materials with the fluorite structures show a pronounced specific heat anomaly well below their melting temperature. This anomaly is a consequence of lattice disorder and is associated with the onset of fast-ion conduction. This paper presents the results of a series of experiments in which the coherent diffuse quasielastic neutron scattering from single crystals of three such fluorite compounds PbF2, SrCl2 and CaF2, was investigated. The diffuse scattering intensity, and its energy width, increases with temperature into the fast-ion phase, and when integrated over energy transfer the intensity exhibits a characteristic variation with scattering vector, falling on an anisotropic shell in reciprocal space and peaking in certain directions. The diffuse intensity indicates that dynamic correlations exist between the defective anions in the fast-ion-phase. A model of short-lived clusters comprising anion Frenkel interstitials, anion vacancies and relaxed anions has been developed which ...
Even though in vivo imaging approaches have witnessed several new and important developments, specimens that exhibit high light scattering properties such as Drosophila melanogaster pupae are still not easily accessible with current optical imaging techniques, Even though in vivo imaging approaches have witnessed several new and important developments, specimens that exhibit high light scattering properties such as Drosophila melanogaster pupae are still not easily accessible with current optical imaging techniques, obtaining images only from subsurface features. This means that in order to obtain 3D volumetric information these specimens need to be studied either after fixation and a chemical clearing process, through an imaging window - thus perturbing physiological development -, or during early stages of development when the scattering contribution is negligible. In this paper we showcase how Optical Projection Tomography may be used to obtain volumetric images of the head eversion process ...
Coating metal nanocrystals with responsive polymers provides a model case of smart, functional materials, where the optical properties can be modulated by external stimuli. However the optical response is highly sensitive to the polymer shell morphology, thickness and dielectric contrast. In this paper we study the nature of cross-linked, thermoresponsive polymer shells for the first time using four different scattering approaches to elucidate the density profile of the shells. Each scattering method provides unique information about the temperature-induced changes of shell thickness in terms of hydrodynamic radius and radius of gyration, the pair-distance distribution functions of the shells as well as the dynamic network fluctuations. Only a combination of these different scattering techniques allows to develop a morphological model of the core-shell particles. We further demonstrate control of the cross-linker distribution in core-shell synthesis by semi-batch precipitation copolymerization. ...
Raman scattering is another phenomenon that involves inelastic scattering of light caused by the vibrational properties of matter. The detected range of frequency shifts and other effects are very different compared to Brillouin scattering. In Raman scattering, photons are scattered by the effect of vibrational and rotational transitions in the bonds between first-order neighboring atoms, while Brillouin scattering results from the scattering of photons caused by large scale, low-frequency phonons. The effects of the two phenomena provide very different information about the sample: Raman spectroscopy can be used to determine the transmitting mediums chemical composition and molecular structure, while Brillouin scattering can be used to measure the materials properties on a larger scale - such as its elastic behavior. The frequency shifts from Brillouin scattering, a technique known as Brillouin spectroscopy, are detected with an interferometer while Raman scattering uses either an ...
TY - JOUR. T1 - Kinetics of the alkaline tetramer → dimer dissociation in liganded human hemoglobin. T2 - A laser light-scattering stopped-flow study. AU - Flamig, D. P.. AU - Parkhurst, L. J.. N1 - Copyright: Copyright 2018 Elsevier B.V., All rights reserved.. PY - 1977. Y1 - 1977. N2 - The first-order dissociation of tetrameric HbCO to the dimer has been studied over the pH range 10.30-11.57 in a light-scattering stopped-flow apparatus using argon-ion laser excitation. The first-order dissociation rate constant varies from 0.25 sec-1 to 24.0 sec-1 over this pH interval. A semilogarithmic plot of k versus pH has a slope of 2.56 at pH 11.07, the midpoint. The pH dependence of the dissociation of the tetramer is consistent with progressive titration of α1-α2 and β1-β2 salt bridges. At pH 10.66 the dissociation rates of HbO2, HbCO, methemoglobin, and HbCN vary less than 20% from their mean value. A study of the dissociation kinetics as a function of protein concentration allows one to obtain ...
Addresses: Rizos AK, Univ Crete, Dept Chem, POB 1527, Heraklion 71409, Crete, Greece. Univ Crete, Dept Chem, Heraklion 71409, Crete, Greece. Univ Crete, Sch Hlth Sci, Heraklion 71110, Crete, Greece. Univ Uppsala, Dept Phys Chem, S-75121 Uppsala, Sweden. FAvailable from: 2008-10-17 Created: 2008-10-17 Last updated: 2011-01-14 ...
Measurement and Simulation of Spontaneous Raman Scattering Spectra in High-Pressure, Fuel-Rich H-Air Flames by (ISBN: 978-1-289-28865-5); Published by Creative Media Partners, LLCin Aug 2013. Compare book prices on to buy books from the lowest price among top online book retailers
A water-soluble beta-D-glucan was obtained from fruiting bodies of Piptoporus betulinus, by hot aqueous extraction followed by freeze-thawing procedure and dialysis. Its molar mass distribution and conformational behavior in solution was assessed by size-exclusion chromatography coupled with multiangle laser light scattering, showing a polysaccharide with an average molecular weight of 2.5 x 10(5) Da with a random coil conformation for molecular weights below 1 x 10(6) Da. Typical signals of beta-(1 -, 3)-linkages were observed in NMR spectrum (delta 102.7/4.76; 102.8/4.74; 102.9/4.52; and delta 85.1/3.78; 85.0/3.77) and also signals of O-6 substitution at delta 69.2/4.22 and 69.2/3.87. The analysis of partially O-methylated alditol acetates corroborates the NMR results, indicating the presence of a beta-D-glucan with a main chain (1 -, 3)-linked, substituted at O-6 by single-units of glucose. The beta-D-glucan showed no toxicity on human colon carcinoma cell line (Caco-2) up to 1000 mu g mL(-1) ...
An experiment to measure the parity violating analyzing power, $A\sb{z}$, in proton-proton scattering at 221 MeV is in progress using the TRIUMF cyclotron. At this beam energy, a unique opportunity exists to isolate the $\sp3P\sb2$-$\sp1D\sb2$ parity mixed partial wave amplitude, which has not been measured before. In terms of the single meson exchange model for the weak nucleon-nucleon interaction, this experiment will determine the weak $\rho$-proton-proton coupling constant, $h\sbsp{\rho}{pp}$. The scale of $A\sb{z}$, which is set by the relative strength of the weak interaction, is of order 10$\sp{-7}$. The goal of the TRIUMF experiment is to determine $A\sb{z}$ to ${\pm}0.2 \times 10\sp{-7}$, which has been achieved in existing measurements at lower energies. The experiment is made extremely challenging by the need to control and minimize coherent fluctuations in the properties of the polarized proton beam, which can introduce large systematic effects to the measured analyzing power. The ...
This book reflects the recent progress made in the field of scattering in polymers. A wide range of scattering studies on different polymer systems, including block copolymers, semicrystalline polymers, complex fluids, multicomponent systems, polymeric surfaces, and polymer processing are included, as well as new experimental techniques and theoretical treatments. This volume provides a comprehensive reference for those researchers who need to know how scattering techniques can be used to tackle different polymer problems, and is ideal for graduate polymer scientists studying scattering techniques.
This book reflects the recent progress made in the field of scattering in polymers. A wide range of scattering studies on different polymer systems, including block copolymers, semicrystalline polymers, complex fluids, multicomponent systems, polymeric surfaces, and polymer processing are included, as well as new experimental techniques and theoretical treatments. This volume provides a comprehensive reference for those researchers who need to know how scattering techniques can be used to tackle different polymer problems, and is ideal for graduate polymer scientists studying scattering techniques.
We plan to study the effect of both oscillatory and steady state shear flow on the mesoscopic structure of polymer blends. A central feature of this proposal is the design and build of a rheometer for use with small angle neutron scattering. This will enable the simultaneous measurement, and hence correlation, of rheological properties and structure. It differs from existing facilities in that it is specifically aimed at viscoelastic materials with a high viscosity. We will study both polystyrene blended with is deuterated analogue, and blends of polystyrene/polyvinylmethylether and polyethyleneoxide/ polymethylmethacrylate. In each case both blend components will be highly entangled. We will meaure the anisotropy of the scattering pattern in the one phase region, and use this information to verify or otherwise recent theoretical predictions. We will also measure the structures that exist within the two-phase region, caused by shear induced phase separation. ...
Due to the large transmural variation in transmembrane potential following the application of strong electric shocks, it is thought that fluorescent photon scattering from depth plays a significant role in optical signal modulation at shock-end. For the first time, a model of photon scattering is used to accurately synthesize fluorescent signals over the irregular geometry of the rabbit ventricles following the application of such strong shocks. A bidomain representation of electrical activity is combined with finite element solutions to the photon diffusion equation, simulating both the excitation and emission processes, over an anatomically-based model of rabbit ventricular geometry and fiber orientation. Photon scattering from within a 3D volume beneath the epicardial optical recording site is shown to transduce differences in transmembrane potential within this volume through the myocardial wall. This leads directly to a significantly modulated optical signal response with respect to that predicted
a/LCI. a/LCI, which is outlined in detail in references ( 11, 12), obtains depth-resolved measurements of the far-field diffraction of a biological sample, which corresponds to a cell monolayer in the present study. Low coherence interferometry permits the rejection of multiply scattered light that can cause noise artifacts in the signal. The signal resulting from an a/LCI measurement is processed to isolate the scattering from individual cell nuclei and all smaller organelles in the ensemble while eliminating contributions from long range correlations within the monolayer ( 24). The processed nuclear scattering profile is then analyzed using an inverse light scattering analysis (ILSA) algorithm to determine the properties of the nucleus (shape, size, etc.). Traditional ILSA algorithms for analyzing scattering from biological samples have generally used Mie theory, a model of spherical scatterers; however, in the present study, the ILSA algorithm uses a T-matrix light scattering model ( 25), ...
Novel graft copolymers of 2-(dimethylamino)ethyl methacrylate (DMAEMA) with N-vinylpyrrolidone (NVP) were designed and synthesized by the free radical copolymerization of DMAEMA with precursor polymers of vinyl-functionalized poly(N-vinylpyrrolidone) (PVP). The ability of the PVP- grafted copolymers to bind and condense DNA was confirmed by ethidium bromide displacement assay, agarose gel electrophoresis and transmission electron microscopy. The presence of PVP in the copolymers had a favorable effect on the biophysical properties of polymer/DNA complexes. Colloidal stable complexes obtained from the copolymer systems, were shown to be separate, uniformly spherical nanoparticles by transmission electron microscopy. The approximate diameter of the complexes was 150-200 nm, as determined by dynamic light scattering studies. These results confirm an important role played by the PVP grafts in producing compact stable DNA complexes. The ζ-potential measurements revealed that the incorporation of the ...
TY - JOUR. T1 - Vibronic coupling in the superoxide anion: The vibrational dependence of the photoelectron angular distribution. AU - Van Duzor, Matthew. AU - Mbaiwa, Foster. AU - Wei, Jie. AU - Singh, Tulsi. AU - Mabbs, Richard. AU - Sanov, Andrei. AU - Cavanagh, Steven. AU - Gibson, Stephen. AU - Lewis, Brenton. AU - Gascooke, Jason. PY - 2010/11/7. Y1 - 2010/11/7. N2 - We present a comprehensive photoelectron imaging study of theO 2(X2∑g, v′ =0-6) ←O 2 - (X2Πg, v″ =0) and O 2 (a 1Δg, v′=0-4)←O 2 -((X2Πg, v″ =0) photodetachment bands at wavelengths between 900 and 455 nm, examining the effect of vibronic coupling on the photoelectron angular distribution (PAD). This work extends the v′ =1-4 data for detachment into the ground electronic state, presented in a recent communication [R. Mabbs, F. Mbaiwa, J. Wei, M. Van Duzor, S. T. Gibson, S. J. Cavanagh, and B. R. Lewis, Phys. Rev. A 82, 011401(R) (2010)]. Measured vibronic intensities are compared to Franck-Condon predictions ...
We present a methodical study of grazing-incidence small-angle x-ray scattering performed in situ during pulsed-laser deposition of Pt on sapphire substrates. From measured two-dimensional intensity distributions in reciprocal space we calculated horizontal and vertical intensity projections and compare them to numerical simulations. The structure of the Pt layers was described using a simple Monte-Carlo model and the Ornstein-Zernicke theory with the Percus-Yevick approximation, and the scattering process was simulated using distorted-wave Born approximation. The validity of the structure models as well as the effect of the indirect scattering processes are discussed. From the comparison of the measured and simulated data we determined the lateral and vertical sizes of surface islands, the surface coverage, the island coalescence, as well as the thickness of the wetting layer at the substrate surface. We studied the time evolution of these parameters and their dependence on the substrate ...
In the present work two nuclei have been investigated by the elastic scattering of charged particles of spin 1/2 from spin 0 nuclei. In the first experiment protons were scattered from He4 yielding information on the compound nucleus Li5. A phase shift analysis of the angular distributions has been done. The results of experiments from 1 to 18 mev of proton bombarding energy have been collected, and the resulting phase shifts have been interpreted in the light of the dispersion theory. In the second experiment He3 nuclei were scattered from He 4 giving information about the compound nucleus Be7. The second excited state of Be7 has been investigated, and the level parameters have been determined. The non-resonant phase shifts show a somewhat anomalous behaviour in the energy range investigated, and these phase shifts have been qualitatively interpreted in terms of other levels in Be7. The phase shift analysis of these experiments has been done on an IBM 650 computer, and as a by-product of the ...
Description. Scattering is a very powerful tool to study the structure of polymers. Written by highly regarded and respected scientists in the field, this book presents the latest developments in the field of scattering in a uniform, systematic manner. This volume arms readers with both theoretical and experimental aspects of the intended area, offering much simplified theoretical explanations on the physics of scattering. The authors provide discussion on applications of experimental techniques. Han and Akcasu begin with a traditional treatment of light scattering from plane waves, followed by consistent application of density (in both real and Fourier space) correlation functions in both space and time. The authors do not distinguish among light, X-ray, and neutron, excepting their scattering length, q-range, coherence and detection differences. Readers can therefore concentrate on exactly the scattering tools they need to use, while theoretical explanation on the physics of scattering can be ...
TY - JOUR. T1 - Solution properties of capsular polysaccharides from Streptococcus pneumoniae. AU - Harding, Stephen E.. AU - Abdelhameed, Ali Saber. AU - Morris, Gordon A.. AU - Adams, Gary. AU - Laloux, Olivier. AU - Cerny, Louis. AU - Bonnier, Benjamin. AU - Duvivier, Pierre. AU - Conrath, Karel. AU - Lenfant, Christophe. PY - 2012/9/1. Y1 - 2012/9/1. N2 - Capsular polysaccharides from ten different serotypes of Streptococcus pneumoniae have been studied with regards their hydrodynamic properties in solution, namely their sedimentation coefficient and molar mass distributions, solution conformations and flexibilities (persistence lengths L p), important properties for the construction of polysaccharide and glycoconjugate vaccines. Sedimentation and molar mass distributions (obtained by sedimentation velocity and equilibrium analysis in the analytical ultracentrifuge supported by size exclusion chromatography coupled to multi-angle light scattering measurements) were generally unimodal, with ...
Efficiency of binary power cycles can be improved by expanding the hydrocarbon working fluids through two-phase region in a turbine and exiting at saturated or superheated condition. This improvement can be achieved if there is no condensation during the expansion or if there is condensation, the droplet size is extremely small. In order to verify this, a particle sizing technique for extremely small particles in flow is needed. In this study, a laser-based technique is developed by which it is possible to detect particles as small at ten angstroms in size. The basis of the technique is that particles of size less than one third of the wavelength of the incident radiation will scatter according to Rayleigh scattering theory. According to this theory, the intensity of the scattered light will be the same in the forward as well as in the backward directions. Therefore, measurement of the scattered intensity at two or three different angles will confirm the presence of Rayleigh scattering. The size ...
Small angle neutron scattering (SANS) has brought insight into how ions are transported at the nano level in stacked membranes of graphene, materials that have many unique properties. The research was aimed to develop graphene into a more versatile material.
D11 is the archetype of a long, pinhole geometry instrument for small angle neutron scattering (SANS), designed for the study of large scale structures in soft matter systems, chemistry, biology, solid state physics and materials science. This instrument was upgraded as a part of the ILLs Millennium Programme. ...
The present study explores the potential use of asymmetrical flow field flow fractionation (aFlFFF) with a multidetection system for the study of metal-alginate interactions. aFlFFF, coupled on-line to a differential refractive index and seven angle laser light scattering detectors was used to provide information on the alginate size distributions. In parallel, the metal distributions of metal-alginate complexes were probed by aFlFFF-high resolution inductively coupled plasma-mass spectrometry. Average values and continuous distributions of molar masses, radiuses of gyration and hydrodynamic radiuses, which are critical for understanding the role of alginates as carriers of metal pollutants, were evaluated in presence of Pb or Cd and compared with those in metal-free solutions of alginate. The values of number average and weight average molar mass, weight average radius of gyration and shape factor for alginate were 150 and 188 kg mol(-1), 53 nm and 1.7, respectively. Alginate molar mass and ...
Cassini made a close flyby of Saturns moon Iapetus on Sept. 10, 2007, and the visual and infrared mapping spectrometer obtained these images during that event. These two images show a higher resolution version of the equatorial region shown in PIA10010. The equatorial region includes the equatorial bulge which shows no differences in these compositions compared to surrounding regions.. The color image on the right shows the results of mapping for three components of Iapetus surface: carbon dioxide that is trapped or adsorbed in the surface (red), water in the form of ice (green), and a newly-discovered effect due to trace amount of dark particles in the ice creating what scientists call Rayleigh scattering (blue). The Rayleigh scattering effect is the main reason why the Earths sky appears blue.. There is a complex transition zone from the dark region, on the right, which is high in carbon dioxide, to the more ice-rich region on the left. Some crater floors are filled with carbon dioxide-rich ...
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Rayleigh scattering is a process in which electromagnetic radiation (including light) is scattered by a small spherical volume of variant refractive indexes, such as a particle, bubble, droplet, or even a density fluctuation. This effect was first modeled successfully by Lord Rayleigh, from whom it gets its name. In order for Rayleighs model to apply, the sphere must be much smaller in diameter than the wavelength (λ) of the scattered wave; typically the upper limit is taken to be about 1/10 the wavelength. In this size regime, the exact shape of the scattering center is usually not very significant and can often be treated as a sphere of equivalent volume. The inherent scattering that radiation undergoes passing through a pure gas is due to microscopic density fluctuations as the gas molecules move around, which are normally small enough in scale for Rayleighs model to apply. This scattering mechanism is the primary cause of the blue color of the Earths sky on a clear day, as the shorter ...
Optical clearing of mouse dermis by glycerol was tested by reflectance-mode confocal microscopy (rCSLM) using 488- nm light. The reflectance signal R(z) was acquired as a function of the depth of the focus (z) within the upper 100 μm of freshly excised mouse dermis. The results specify the scattering coefficient (μs [cm-1]) and the anisotropy of scattering (g [dimensionless]). The absorption is too low to exert an effect. The results, published in Samatham et al., Journal of Innovative Optical Health Sciences 2010, 3(3):183-188, described how the clearing effect of glycerol was to increase g toward nearly 1.0, while having only a modest effect on μs. In other words, glycerol caused light scattering to become very forward-directed, but did not strongly alter the number of scattering events per unit length of photon path. This paper discusses the possible mechanism of action that is responsible for this clearing effect ...
0055] In the external light extraction, an external scattering layer may be manufactured in a sheet shape and then is attached to the substrate external through a similar method of forming an MLA sheet. Or, an external scattering layer may be manufactured by coating a substrate with a manufactured solution and hardening the coated substrate. Since there is no color change and interference color according to a viewing angle in the external scattering layer and Lambertian distribution is maintained after light passes through a light scattering layer, this light extraction structure may be applicable to a white OLED lighting panel. However, if a light scattering layer becomes thicker and light scattering particles form a multi layered structure, scattering effect of a short wavelength becomes greater than that of a long wavelength so that a transmission color has yellowish red. This should be taken care of. In order to minimize a spectrum change due to a scattering effect difference according to a ...
The information determined relates to the particle size, shape, distribution and orientation, porosity, surface features and internal structure.. A SAXS sample requires very little preparation and results are representative of the bulk material. The scattered signal is typically recorded at diffraction angles of ,6° and the sample is positioned at a long distance from the detector. The measured scattered signals are accordingly extremely weak. For this reason, SAXS measurements benefit from the use of a high brilliance X-ray source such as the MetalJet, which makes weak scattering effects, stronger, more visible and more readily studied.. ...
The kinetics of kraft lignin (KL) aggregation at alkaline conditions was studied by quasi-elastic light scattering (QELS) and turbidity measurements. Stability ratios (W) for HL were obtained at 70 degreesC and various concentrations of sodium chloride. By analyzing the early-time evolution data of aggregate growth obtained from QELS, fractal dimensions of flocs formed in both reaction-limited cluster-cluster aggregation regimes and diffusion-limited cluster-cluster aggregation regimes were determined. Correlations between the fractal dimension and the W-ratio were found in accordance to recent studies of a system containing monodisperse polystyrene colloids. By cryogenic transmission electron microscopy, the fractality of KL aggregate structures in the system was also shown. It was seen from stability studies of KL solutions that the effects of specific co- and counterions follow the Hofmeister series. From the outcome of the investigation, different modes of aggregation occurring in a KL ...
Measurements of the scattering cross section of a number of bare soils have been made with CO/sub 2/ laser illumination at 10.59 /spl mu/m. The primary foc
The type VI secretion system (T6SS), a multisubunit needle-like apparatus, has recently been found to play a role in interspecies interactions. The Gram-negative bacteria harboring T6SS (donor) deliver the effectors into their neighboring cells (recipient) to kill them. Meanwhile, the cognate immunity proteins were employed to protect the donor cells against the toxic effectors. Tae4 (type VI amidase effector 4) and Tai4 (type VI amidase immunity 4) are newly identified T6SS effector-immunity pairs. Here, we report the crystal structures of Tae4 from Enterobacter cloacae and Tae4-Tai4 complexes from both E. cloacae and Salmonella typhimurium. Tae4 acts as a DL-endopeptidase and displays a typical N1pC/P60 domain. Unlike Tsi1 (type VI secretion immunity 1), Tai4 is an all-helical protein and forms a dimer in solution. The small angle x-ray scattering study combined with the analytical ultracentrifugation reveal that the Tae4-Tai4 complex is a compact heterotetramer that consists of a Tai4 dimer ...
S. B. Anantharaman et al., Strongly Red-Shifted Photoluminescence Band Induced by Molecular Twisting in Cyanine (Cy3) Dye Films, The Journal of Physical Chemistry C, 2017, DOI: 10.1021/acs.jpcc.7b01412 (open access). Besides in silver halide photography, industrial applications of dye aggregates are hampered due to difficulties in producing aggregates reproducibly, with controlled size and perfection and avoiding complex manufacturing processes such as Langmuir-Blodgett techniques.. While cyanine dye aggregates are best known for intense and narrow absorption bands, our films stick out for prominent scattering in the absorption band (resonance light scattering). Similar to localized surface plasmon resonances (LSPR), scattering can be explained with the coherently oscillating electron cloud of the aggregate in response to incident light. Because dye aggregate extinction has narrowest bandwidths, the wavelength selectivity exceeds the ...
Infrared radiation can pass more freely through regions of cosmic dust that scatter visible light. Observations in infrared ... Radiation Scattering in Optical Systems. 257. pp. 19-28. Bibcode:1981SPIE..257...19F. doi:10.1117/12.959598. "NASA JWST FAQ " ... The JWST will be sensitive to a range of wavelengths from 0.6 (orange light) to 28 micrometers (deep infrared radiation at ... Relatively cool objects (temperatures less than several thousand degrees) emit their radiation primarily in the infrared, as ...
Harrington's further work included the study of radiation and scattering in bodies of revolution, dielectric scattering, field ... Mautz, J. R.; Harrington, R. F. (1969). "Radiation and scattering from bodies of revolution". Applied Scientific Research ... McLean, James S. (May 1996). "A re-examination of the fundamental limits on the radiation Q of electrically small antennas". ... Electromagnetic Scattering. New York: Academic Press. p. 429-470. ISBN 9780323142434. Harrington, Roger F. (2003). Introduction ...
ISBN 978-1-4020-0048-5. Kuzmin, Arkady (January 2002). Scattering of the low frequency Pulsar Radiation. p. 53. ISBN 978-1-4020 ... 5. Book citation: Sources and Scintillations: Refraction and Scattering in Radio Astronomy. Edited by Richard Strom, Peng Bo, ...
Perry Sprawls, Ph.D. (Fall 2013). "Scattered Radiation and Contrast". Sprawls Educational Foundation. Retrieved ... Scattered x-rays do not travel in parallel to rays that pass directly through the patient. The quantity of scattering depends ... This leads to increase in the amount of radiation absorbed by the patient. Scatter rejection grids are therefore omitted where ... The grid is positioned on the opposite side of the patient from the x-ray tube to reduce the quantity of scattered x-rays that ...
His first atmospheric radiation teacher was Bruce Barkstrom. He is married to Nanette Malott Bohren. Bohren, Craig (2006). ... ISBN 978-3-527-40503-9. Bohren, Craig (1998). Absorption and Scattering of Light by Small Particles. New York: Wiley. ISBN 978- ... He is an author of about 100 articles mostly on atmospheric optics, radiative transfer, and light scattering. ... Bohren wrote fundamental books on light scattering, atmospheric thermodynamics, and radiative transfer, as well as popular ...
stimulated Thomson scattering. *betatron radiation [1]. Applications[edit]. Applications of coherent X-ray radiation include ... An X-ray laser is a device that uses stimulated emission to generate or amplify electromagnetic radiation in the near X-ray or ... The emitted radiation, based on amplified spontaneous emission, has relatively low spatial coherence. The line is mostly ... An example is the capillary neon-like Ar8+ laser (generating radiation at 47 nm). ...
Three-dimensional wave-envelope elements of variable order for acoustic radiation and scattering. Part I. Formulation in the ... Mapped wave envelope elements for acoustical radiation and scattering. Journal of Sound and Vibration, 170(1), 97-118. Astley, ... Lidoine, S., & Caruelle, B. (2005, July). Fan noise radiation from intake: Comparisons between FEM predictions and fan rig test ... Achunche, I., Astley, J., Sugimoto, R., & Kempton, A. (2009). Prediction of forward fan noise propagation and radiation from ...
Vishveshwara, C. V. (1970). "Scattering of Gravitational Radiation by a Schwarzschild Black-hole". Nature. Springer Science and ... Gravitational Radiation and the Universe: Essays in Honour of C.V.Vishveshwara,- Bala R. Iyer and Biplab Bhawal(eds)", (Kluwer ...
... performing and analyzing X-ray Raman scattering experiments". Journal of Synchrotron Radiation. 22 (2): 400-409. doi:10.1107/ ... It utilizes the technique of X-ray Raman scattering (XRS), also known as Non-resonant Inelastic X-Ray Scattering (NIXS) to ... Th is the Thomson scattering cross-section (representing the elastic scattering of electromagnetic waves off electrons) and S(q ... The non-resonant inelastic x-ray scattering cross section is orders of magnitude smaller than that of photoelectric absorption ...
"Nonlinear Thomson scattering in the strong radiation damping regime". American Institute of Physics. Archived from the original ... Raman scattering, interaction of photons with optical phonons. Nonlinear effects fall into two qualitatively different ... Stimulated Brillouin scattering, interaction of photons with acoustic phonons Multi-photon absorption, simultaneous absorption ... Optical phase conjugation is implemented via stimulated Brillouin scattering, four-wave mixing, three-wave mixing, static ...
Atmospheric radiation - solar spectrum. Atmospheric scattering, spectra of water vapor and other gases. Albedo of earth and ... 1931). Radiation effects on man in space. Bull. Amer. Meteorol. Society. 3:, 183. Büttner, K. (1932). Physical considerations ... Heat transfer pipe and convection, evaporation and radiation in Bioclimatology and meteorology.) Link, M. M. (1965). Space ... evaporation and radiation in Bioklimatologie and Meteorology", at the University of Kiel. He became head of the Bioclimatic ...
Radiation shielding to protect people and the environment from the harmful effects of ionizing radiation. Containment buildings ... Neutrons are uncharged, this allows them to penetrate deep in the target and close to the nuclei, thus scattering neutrons by ... nuclear forces, some nuclides are scattered large. The nuclear cross section of uranium-235 for slow thermal neutrons is about ... which are designed to contain the escape of radiation in an emergency. Instrumentation to monitor and control the reactor's ...
The net radiation arriving at rscreen is the sum of all the scattered waves throughout the crystal ... Scattering techniques[edit]. Further information: X-ray scattering techniques. Elastic vs. inelastic scattering[edit]. X-ray ... amplitude of scattered wave. =. A. e. i. k. ⋅. r. S. f. (. r. ). d. V. ,. {\displaystyle {\text{amplitude of scattered wave}}=A ... Synchrotron radiation[edit]. Synchrotron radiation sources are some of the brightest light sources on earth and are some of the ...
This scattering model has found use in other scientific disciplines. The crater Henyey on the Moon is named after him, as is ... CS1 maint: discouraged parameter (link) "The Henyey-Greenstein phase function" (PDF). "Diffuse radiation in the Galaxy". ... CS1 maint: discouraged parameter (link) "The Henyey-Greenstein scattering function". Archived from the original on 2014-11-02. ... Missing or empty ,url= (help) "Scattering: The Henyey-Greenstein phase function". "Discovery Circumstances: Numbered Minor ...
"High-Resolution Bulk Magnetic Scattering of High-Energy Synchrotron Radiation". Europhysics Letters. 27 (7): 537-541. Bibcode: ... It has found applications in very diverse areas such as atomic systems synchrotron radiation and derivation of the Bloch ...
Wu, C. S.; Shaknov, I. (1950). "The Angular Correlation of Scattered Annihilation Radiation". Physical Review. 77 (1): 136. ... "The Angular Correlation of Scattered Annihilation Radiation". Physical Review. 77: 136. doi:10.1103/PhysRev.77.136. ... "Women in Radiation History: Chien-Shiung Wu". March 4, 2021. Chiang 2014, pp. 184-185. Wang 1970-1980, p. 368. sfn error: no ... Yuan showed her the Radiation Laboratory, where the director was Ernest O. Lawrence, who would soon win the Nobel Prize for ...
Wu, C. S.; Shaknov, I. (1950). "The Angular Correlation of Scattered Annihilation Radiation". Physical Review. 77 (1): 136. ...
Wu, C. S.; Shaknov, I. (1950). "The Angular Correlation of Scattered Annihilation Radiation". Physical Review. 77 (1): 136. ... Pryce, M. H. L.; Ward, J. C. (1947). "Angular Correlation Effects with Annihilation Radiation". Nature. 160 (4065): 435. ... compression and radiation implosion. At a meeting on 2 December 1955, Ward sketched it on the blackboard. Penny's response was ...
Wu, C. S.; Shaknov, I. (1950). "The Angular Correlation of Scattered Annihilation Radiation". Physical Review. 77 (1): 136. ... Pryce, M. H. L.; Ward, J. C. (1947). "Angular Correlation Effects with Annihilation Radiation". Nature. 160 (4065): 435. ... "for their joint researches on the radiation phenomena discovered by Professor Henri Becquerel", and Henri Becquerel, "for his ...
It also reflects and scatters UV. Bisoctrizole is a hybrid UV absorber, an organic UV filter produced in microfine organic ... Bisoctrizole is a broad-spectrum ultraviolet radiation absorber, absorbing UVB as well as UVA rays. ...
This ionising radiation may cause damage to materials within both the tether and climbers. An obvious option would be for the ... High-Voltage Tethers For Enhanced Particle Scattering In Van Allen Belts. 38. College Park, MD: American Physical Society, ... This is not a problem for most freight, but the amount of time a climber spends in this region would cause radiation poisoning ... The best radiation shielding is very mass-intensive for physical reasons. Alternatively, the shielding itself could in some ...
In Thomson scattering a charged particle emits radiation under incident light. The particle may be an ordinary atomic electron ... If X dV dΩ dλ is the energy scattered by a volume element dV into solid angle dΩ between wavelengths λ and λ+dλ per unit time ... Emission of radiation is typically described using semi-classical quantum mechanics: the particle's energy levels and spacings ... Interaction with electromagnetic radiation is used in fluorescence spectroscopy, protons or other heavier particles in Particle ...
... while in the scattering (radiation) force the incident photons travel in the same direction and 'scatter' isotropically. By ... Harada Y, Asakura T (1996). "Radiation Forces on a dielectric sphere in the Rayleigh Scattering Regime". Optics Communications ... The laser radiation can be fixed in wavelength such as that of an argon ion laser or that of a tunable dye laser. Laser power ... Under the Rayleigh approximation, we can also write the scattering force as F scat ( r ) = k 4 α 2 6 π c n 0 3 ϵ 0 2 I ( r ) z ...
This leaves emission of radiation from targets and scattering of neutrons. For neutron detectors to be portable, they must be ... Soil absorbs radiation from the Sun and is heated, with a resulting change in the infrared radiation that it emits. Landmines ... Bom, V.; Ali, M.A.; van Eijk, C.W.E. (February 2006). "Land mine detection with neutron back scattering imaging using a neutron ... They may be placed by hand or scattered from airplanes, in regular or irregular patterns. In urban environments, fragments of ...
Radiation damping acts as a limiting factor for the plasmonic excitations in surface-enhanced Raman scattering. The damping ... Max Abraham Hendrik Lorentz Lorentz force Cyclotron radiation Synchrotron radiation Electromagnetic mass Radiation resistance ... 2006). "Contributions from radiation damping and surface scattering to the linewidth of the longitudinal plasmon band of gold ... Wokaun, A.; Gordon, J. P.; Liao, P. F. (5 April 1952). "Radiation Damping in Surface-Enhanced Raman Scattering". Physical ...
... and back-scattered light is reflected light. The scattering and extinction ("dimming") of the radiation gives useful ... Dust particles can scatter light nonuniformly. Forward scattered light is light that is redirected slightly off its path by ... For example, if the object(s) in one's data is many times brighter in forward-scattered visible light than in back-scattered ... the wavelength of the electromagnetic radiation, and on the nature of the grain: its refractive index, size, etc. The radiation ...
Nanofluid Absorption Fluid Radiation Scattering Solar collector Solar energy Taylor, Robert A.; Otanicar, Todd; Rosengarten, ... An ideal solar collector will absorb the concentrated solar radiation, convert that incident solar radiation into heat and ... On reaching the receiver the solar radiations transfer energy to the nanofluid via scattering and absorption. ... solar collectors are solar thermal collectors where nanoparticles in a liquid medium can scatter and absorb solar radiation. ...
Scattering of thorium C″ γ-radiation by radium G and ordinary lead". The London, Edinburgh, and Dublin Philosophical Magazine ... This is because there are just two main decay methods: alpha radiation, which reduces the mass by 4 atomic mass units (amu), ... On Earth, most of the starting isotopes of these chains before 1945 were generated by cosmic radiation. Since 1945, the testing ...
Scattering of thorium C″ γ-radiation by radium G and ordinary lead". The London, Edinburgh, and Dublin Philosophical Magazine ...
The interaction of an aerosol with radiation is quantified by the single-scattering albedo (SSA), the ratio of scattering alone ... as this affects the net amount of radiation absorbed or scattered to space. e.g. if a highly scattering aerosol is above a ... This leads to more scattering of shortwave radiation i.e. an increase in the albedo of the cloud, known as the Cloud albedo ... Organic matter influences the atmospheric radiation field by both scattering and absorption. Some aerosols are predicted to ...
It is one of several birds in the crow family designated magpies, and belongs to the Holarctic radiation of "monochrome" ... The preferred habit is open countryside with scattered trees and magpies are normally absent from treeless areas and dense ...
... of sunlight in Earth's atmosphere causes diffuse sky radiation, which is the reason for the blue color of ... In this case, the Rayleigh scattering intensity for a single particle is given in CGS-units by[16] I. =. I. 0. 8. π. 4. α. 2. λ ... The particle, therefore, becomes a small radiating dipole whose radiation we see as scattered light. The particles may be ... Rayleigh scattering applies to the case when the scattering particle is very small (x ≪ 1, with a particle size , 1 /10 ...
"Chapter 9 Occupational Exposure to Radiation]" (PDF). Radiation, People and the Environment. IAEA. pp. 39-42. Archived from the ... Two major sources of noise in PET are scatter (a detected pair of photons, at least one of which was deflected from its ... Information for Radiation Worker, Nuclear Regulatory Commission *^ Brix G; Lechel U; Glatting G; Ziegler SI; et al. (April 2005 ... The amount of radiation in 18F-FDG is similar to the effective dose of spending one year in the American city of Denver, ...
Maloney, S. K.; Moss, G.; Mitchell, D. (2 August 2005). "Orientation to solar radiation in black wildebeest (Connochaetes gnou ... The black wildebeest is particularly susceptible to anthrax, and rare and widely scattered outbreaks have been recorded and ... It shows well-developed orientation behaviour towards solar radiation, which helps it thrive in hot, and often shadeless, ...
Very light sensitive; sensitive to scattered light Not very light sensitive; sensitive to only direct light ... The great biological importance of photoreceptors is that they convert light (visible electromagnetic radiation) into signals ...
Radiation dose[edit]. The dosage of radiation applied in radiography varies by procedure. For example, the effective dosage of ... A Bucky-Potter grid may be placed between the patient and the detector to reduce the quantity of scattered x-rays that reach ... Radiography is an imaging technique using X-rays, gamma rays, or similar ionizing radiation and non-ionizing radiation to view ... DeWerd LA, Wagner LK (January 1999). "Characteristics of radiation detectors for diagnostic radiology". Applied Radiation and ...
Energy of electromagnetic radiation.. Radiant energy density. we. joule per cubic metre. J/m3. M⋅L−1⋅T−2. Radiant energy per ... Spectral radiant flux absorbed and scattered by a volume per unit length, divided by that received by that volume.. ... W., Petty, Grant (2006). A first course in atmospheric radiation. Sundog Pub. ISBN 9780972903318. OCLC 932561283.. ... Radiant flux absorbed and scattered by a volume per unit length, divided by that received by that volume.. ...
The refractive index of electromagnetic radiation equals n. =. ε. r. μ. r. ,. {\displaystyle n={\sqrt {\varepsilon _{\mathrm {r ... However, some net energy will be radiated in other directions or even at other frequencies (see scattering). ... Attwood, David (1999). Soft X-rays and extreme ultraviolet radiation: principles and applications. p. 60. ISBN 978-0-521-02997- ... Feynman, Richard P. (2011). Feynman Lectures on Physics 1: Mainly Mechanics, Radiation, and Heat. Basic Books. ISBN 978-0-465- ...
By neutrino-electron scattering, ν. x. +. e. −. →. ν. x. +. e. −. {\displaystyle \nu _{\text{x}}+e^{-}\to \nu _{\text{x}}+e ... Mounted on an inside superstructure are about 13,000 photomultiplier tubes that detect light from Cherenkov radiation. A ... Super-Kamiokande was able to detect elastic scattering (ES) events ν. x. +. e. −. →. ν. x. +. e. −. {\displaystyle \nu _{x}+e ... scattering, has a relative sensitivity to ν. e. {\displaystyle \nu _{e}}. s and heavy-flavor neutrinos of ∼7:1.[15] Since the ...
Lovesey, S. W. (1984). Theory of Neutron Scattering from Condensed Matter; Volume 1: Neutron Scattering. Oxford: Clarendon ... that partly describe a body of matter or radiation. It states that the behavior of those variables is subject to general ... Lovesey, S. W. (1984). Theory of Neutron Scattering from Condensed Matter; Volume 2: Condensed Matter. Oxford: Clarendon Press ... Squires, G.L. (1996). Introduction to the Theory of Thermal Neutron Scattering (2nd ed.). Mineola, New York: Dover Publications ...
William Herschel, previously a clarinet player, of Bath discovered infrared radiation on 11 February 1800, and the planet ... indicated by scatters of flints.[36] The Neolithic people continued to exploit the reed swamps for their natural resources and ...
... and lack the Dyck texture feathers that-in the Psittacidae-scatter light to produce the vibrant colours of so many parrots. ... "Molecular systematics of two enigmatic genera Psittacella and Pezoporus illuminate the ecological radiation of Australo-Papuan ... diversification of parrots supports a taxon pulse model with multiple trans-oceanic dispersal events and local radiations". ...
Radiation damping. Light scattering. *Polarization. *Relativistic effects in radiation. *Color vision. *Mechanisms of seeing ... Volume I: Mainly mechanics, radiation, and heatEdit. Preface: "When new ideas came in, I would try either to deduce them if ... The first volume focuses on mechanics, radiation, and heat, including relativistic effects. The second volume covers mainly ...
Yeast carry one or two copies of each histone gene, which are not clustered but rather scattered throughout chromosomes. ... It also protects DNA from getting destroyed by ultraviolet radiation of sun. ...
His remains were cremated and the ashes were scattered according to Hindu tradition in a private ceremony in the Ganges and ... "George Harrison Receives Radiation Treatment". ABC News. Archived from the original on 4 June 2011. Retrieved 2 April 2010 ... His close family scattered his ashes according to Hindu tradition in a private ceremony in the Ganges and Yamuna rivers near ...
"Transparent Radiation" was awarded 'Single of the Week' by Sounds, and matched the previous single in reaching no. 29 on the ... This is Spacemen 3 in bloom, midsummer before the seeds were scattered, right at the point where we worked together well and in ... Whilst working on the album, "Transparent Radiation" - a cover of a song by the Red Crayola - was recorded, and released as a ... "Transparent Radiation", "Revolution", "Suicide", "Set Me Free", "Che" and "Let Me Down Gently" [Kember]; and "Take Me to the ...
a b c d e Yurko, V.V. (2016). Diet of the White-Tailed Eagle During the Breeding Season in the Polesski State Radiation- ... scattered pairs in both now with reintroductions factoring in the Czech Republic), Hungary, and Bulgaria.[1][3] In Denmark ( ... Scattered pockets of wintering birds are known to occur too in central and southern China, into northeastern Myanmar, and more ...
"for his services in the investigation of the structure of atoms and of the radiation emanating from them"[۸۵] ... "for his pioneering studies of electron scattering in atomic nuclei and for his thereby achieved discoveries concerning the ... "for his pioneering investigations concerning deep inelastic scattering of electrons on protons and bound neutrons, which have ...
They occur in scattered groves, with a total of 68 groves (see list of sequoia groves for a full inventory), comprising a total ... Loose ground ash may also act as a cover to protect the fallen seeds from ultraviolet radiation damage. Due to fire suppression ...
Water vapor is an invisible gas, but the clouds of condensed droplets refract and scatter the sunlight and are thus visible. ... Heat (energy) can also be received by radiation from any hot refractory wall of the combustion chamber. ...
Rutherford scattering Differential cross-section (non-identical particles in a coulomb potential): d. σ. d. Ω. =. (. 1. n. ). d ... Absorbed dose, total ionizing dose (total energy of radiation transferred to unit mass) D can only be found experimentally N/A ... Nuclear scattering theory[edit]. The following apply for the nuclear reaction: a + b ↔ R → c. in the centre of mass frame, ...
At this time, he began using synchrotron radiation and devised techniques which combine X-ray spectroscopy and high-resolution ... A technique in three-dimensional nanostructural analysis based on Rutherford scattering". Chemical Communications (10): 907. ...
Synchrotron Radiation News, Issue 15(5), p. 35-42, 2002. ... The scattered probe is either photons (grazing-incidence small- ... The diffuse scattering from the sample (red arrow) is recorded with an area detector. As an example the scattering from a block ... Grazing-incidence small-angle scattering (GISAS) is a scattering technique used to study nanostructured surfaces and thin films ... In combination with the straightforward scattering geometry, where all relevant information is contained in a single scattering ...
In a series of pioneering scattering experiments Ernest Rutherford at the University of Manchester discovered the internal ... For example, ultraviolet electromagnetic radiation is not transferred with as much efficacy from one substance to another as ...
The Earth has an albedo of 0.3, meaning that 30% of the solar radiation that hits the planet gets scattered back into space ... Solar Radiation and the Earth's Energy Balance *^ "Introduction to Solar Radiation". Newport Corporation. Archived from the ... See also: Black body, Black-body radiation, Planck's law, and Thermal radiation ... The fact that the energy density of the box containing radiation is proportional to T. 4. {\displaystyle T^{4}}. can be derived ...
"Cosmic radiation" redirects here. For some other types of cosmic radiation, see Cosmic background radiation and Cosmic ... 1988). "A study of Bhabha scattering at PETRA energies". Zeitschrift für Physik C Particles and Fields. 37 (2): 171-177. doi: ... Average annual radiation exposure (millisieverts) Radiation UNSCEAR[83][84] Princeton[85] Wa State[86] MEXT[87] Remark ... Role in ambient radiation. Cosmic rays constitute a fraction of the annual radiation exposure of human beings on the Earth, ...
Although spectrophotometry is most commonly applied to ultraviolet, visible, and infrared radiation, modern spectrophotometers ... Inelastic neutron scattering. *Laser-induced breakdown spectroscopy. *Mössbauer spectroscopy. *Neutron spin echo ... but infrared measurement is also challenging because virtually everything emits IR light as thermal radiation, especially at ...
Colour is the most obvious property of a mineral, but it is often non-diagnostic.[72] It is caused by electromagnetic radiation ... Iridescence is a variety of the play of colours where light scatters off a coating on the surface of crystal, cleavage planes, ...
ions absorb solar radiation around 1.54 µm. Two Er3+. ions that have absorbed this radiation can interact with each other ... Nanoparticle coatings inducing plasmonic light scattering increase wide-angle conversion efficiency up to 3%. Optical ... Each layer has a different band gap energy to allow it to absorb electromagnetic radiation over a different portion of the ... They are used as a photodetector (for example infrared detectors), detecting light or other electromagnetic radiation near the ...
... scattering wireless environment. BLAST was developed by Gerard Foschini at Lucent Technologies' Bell Laboratories (now Alcatel- ... Mobile phone radiation and health. *Wireless electronic devices and health. *. International Telecommunication Union. (Radio ... "V-BLAST: An Architecture for Realizing Very High Data Rates Over the Rich-Scattering Wireless Channel". Proc. URSI ISSSE: 295 ...
Purchase The Scattering of Light and Other Electromagnetic Radiation - 1st Edition. Print Book & E-Book. ISBN 9781483200217, ... 3.11 Radiation Pressure. Chapter 4. The Scattering Functions for Spheres. 4.1 Scattering Coefficients 4.2 Efficiency Factors ... The Scattering of Light and other Electromagnetic Radiation covers the theory of electromagnetic scattering and its practical ... The Scattering of Light and Other Electromagnetic Radiation 1st Edition. 0.0 star rating Write a review ...
Optical tomography based on spectral correlations of scattered radiation Author(s): Yuri T. Mazurenko ... of highly scattering objects based on the measurements of correlation characteristics of the spectrum of scattered radiation. ...
To better understand the potential impact of scatter radiation Dr. Ch...,Scatter,Radiation,from,Mammography,Presents,No,Cancer, ... 27 2012 -- The radiation d... Thyroid shields can impede good mammographic quality and therefore ...During mammography some X- ... rays scatter away from the primary beam in ... ... Scatter Radiation from Mammography Presents No Cancer Risk. ... ... Based on the extremely low scatter radiation dose to the thyroid -- equivalent to just a few minutes of background radiation ...
... ... Home » Emission of electromagnetic radiation by coherent vibrational waves in stimulated Raman scattering ... Stimulated Raman scattering of a laser in a plasma with clusters. Tiwari, Pawan K.; Tripathi, V. K. // Physics of Plasmas; ... A Raman-scattering study of the vibrational modes in a BiB3O6 crystal was conducted at room temperature. The numbers of ...
Investigation of multiple scattering contribution to transmission of radiation in scale model clouds Author(s): Wladyslaw W. ... The measuring technique is based on simultaneous observation of transmitted and scattered light fluxes in growing aerosol ... was negligibly affected by multiple scattering. Modeling of transmittance was performed using a solution of the radiative ... whereas the small angle approximation considerably underestimated the multiple scattering contributions to the transmitted ...
An algorithm for the suppression of the radiation and scattering fields created by vibration of the smooth closed surface of a ... Algorithm for Active Suppression of Radiation and Acoustical Scattering Fields by Some Physical Bodies in Liquids Vladimir V. ... An algorithm for the suppression of the radiation and scattering fields created by vibration of the smooth closed surface of a ... Arabadzhi, V.V. Algorithm for Active Suppression of Radiation and Acoustical Scattering Fields by Some Physical Bodies in ...
... the slice thickness approximately doubled the scattered radiation level. The scattered radiation dose at each kV setting was ... Scattered Radiation Level During Computed Tomography Fluoroscopy. CB Chan, LK Chan, HS Lam. Department of Radiology, Kwong Wah ... Conclusion: The results of this study (in the form of the linear equations obtained) enable the scattered radiation dose to be ... Objective: To assess the scattered radiation dose to personnel during CT fluoroscopy using phantom measurements. Materials and ...
Influence of aerosol multiple scattering of ultraviolet radiation on martian atmospheric sensing. ... scattering properties (asymmetry parameter and single scattering albedo), ground albedo, and O3 content as well as MER long- ... We show that due to the fact that the distributions of absorbing (ozone) and scattering (aerosols) agents are vertically ... The ultraviolet (UV) radiative transfer problem in the martian atmosphere is dominated by multiple scattering of photons with ...
The radiation dose to areas of the body near the breast during mammography is negligible, or very low, and does not result in ... Although this scatter radiation is much weaker than the primary beam, there has been concern that women exposed to it during ... Scatter radiation from mammography does not increase risk of cancer. Share this content: *facebook ... Based on the extremely low scatter radiation dose to the thyroid, which is equivalent to just a few minutes of background ...
The presence of scattered radiation leads to a loss of spatial contrast and, more importantly, a bias in radio-graphic material ... Once validated through simulations and experimentally, this tool gave the ability to study the behavior of scattered radiation ... Based on the conducted scatter analysis, a Partial Attenuation Spectral Scatter Separation Approach (PASSSA) adapted for multi- ... The main aim of the present thesis was to develop a scatter correction approach adapted for multi-energy imaging. In order to ...
hanced anomalous scattering data of TL using Cr Kα radiation has not been attempted before. ... R. Shankaranarayanan for extending his lab facilities to collect anomalous scattering datasets using Cr Kα radiation. ... The use of chromium-anode X-ray radiation is very useful for SAD experiments. The anomalous scattering signal is more than ... C. T. Lemke, G. D. Smith and P. L. Howell, "S-SAD, Se-SAD and S/Se-SIRAS Using Cu Kα Radiation: Why Wait for Synchrotron Time ...
The object is radiated at a number of points near the exterior of the object, and the radiation emerging from the object is ... The system computes the intensity of radiation that would emerge from the object at the exit points if the interior of the ... The final values of the scattering and attenuation coefficients from this process are mapped so as to generate a series of ... Each voxel is modelled as having scattering and attenuation properties, represented by numerical coefficients. ...
... by Synchrotron Radiation Grazing Incidence X-Ray Scattering and Diffraction ... Ion Implantation, Metallic Quantum Dots, Non-Linear Optical Materials, Small Angle X-Ray Scattering, X-Ray Diffraction (XRD) ... Characterization of Cu Metallic Clusters in Amorphous SiO2 by Synchrotron Radiation Grazing Incidence X-Ray Scattering and ... Characterization of Cu Metallic Clusters in Amorphous SiO2 by Synchrotron Radiation Grazing Incidence X-Ray Scattering and ...
... samples using synchrotron radiation 1 X-ray diffraction Scattering studies of muscle contraction using synchrotron radiation ... Synchrotron Radiation VI Analyses of biological samples using synchrotron radiation 3 Research on radiation damage to DNA using ... Radiation Physics and Chemistry 80(10): 999-1000, 2011. Synchrotron Radiation III Measurement by synchrotron radiation 9 X-ray ... Synchrotron Radiation VI Analyses of biological samples using synchrotron radiation 1 X-ray diffraction Scattering studies of ...
The particle scatters the light and the scattered light is detected using a detector. The detector creates a digital signal ... The ratio of the scattered light intensity from larger scattering angles to the smaller scattering angles approaches unity as ... or radiation generating alpha, beta, or gamma radiation; any of which chemical, biological, or radiation (CBR) agents that may ... The scattered radiation pattern produced by an object in flowcell 1310 is reflected by reflective optical element 1312. The ...
Discussion concerning ill-conditioned kernel matrices when retrieving particle size distributions based on scattered radiation ... "Discussion concerning ill-conditioned kernel matrices when retrieving particle size distributions based on scattered radiation ... Vector similarity measure for particle size analysis based on forward light scattering Bin Hu, Jianqi Shen, and Tianxiong Duan ... Size distribution of mineral aerosol: using light-scattering models in laser particle sizing Ben Veihelmann, Martin Konert, and ...
Influence of the Raman depolarisation ratio on far-field radiation patterns in coherent anti-Stokes Raman scattering (CARS) ...
AIM analysis of scattering and radiation by arbitrary surface-wire configurations. Authors: Ewe, W.-B. Li, L.-W. Chang, C.-S. ... Ewe, W.-B., Li, L.-W., Chang, C.-S., Xu, J.-P. (2007-01). AIM analysis of scattering and radiation by arbitrary surface-wire ... The adaptive integral method is utilized to solve electromagnetic scattering and radiation problems of conducting surface-wire ...
UV Radiation;Scattering;Cloud Optical Thickness;Solar Radiation Model; ... The Variation of UV Radiation by Cloud Scattering at King Sejong Station in West Antarctica - ... In solar radiation model, the UV radiation was less scattered with increase of ice crystal size in cloud and this scattering ... The Variation of UV Radiation by Cloud Scattering at King Sejong Station in West Antarctica. Lee, Kyu-Tae; Lee, Bang-Yong; Won ...
Synchrotron radiation facilities are pillars of modern structural biology. Small-Angle X-ray scattering performed at ... Combined small angle X-ray solution scattering with atomic force microscopy for characterizing radiation damage on biological ... Combined small angle X-ray solution scattering with atomic force microscopy for characterizing radiation damage on biological ... A major challenge with high-energy X-ray beam on such macromolecules is the perturbation of sample due to radiation damage. By ...
The resulting solutions are used to calculate the scattering amplitude. As a numerical application, the case of a red blood ... Contributors: N/A.A mathematical formalism describing plane electromagnetic wave scattering by a linear chain of N triaxial ... The corresponding integral equation for the scattering, which contains N singular kernels, is transformed into N non-singular ... Subjects: Electromagnetic wave scattering, Fourier transforms, Matrix algebra, Refractive index, Cells, Electromagnetic ...
Greater scattered radiation was found behind the gantry for head scanning (20 vs. 16 μGy for a body scan) while greater scatter ... Greater scattered radiation was found behind the gantry for head scanning (20 vs. 16 μGy for a body scan) while greater scatter ... Greater scattered radiation was found behind the gantry for head scanning (20 vs. 16 μGy for a body scan) while greater scatter ... Greater scattered radiation was found behind the gantry for head scanning (20 vs. 16 μGy for a body scan) while greater scatter ...
An analysis based on a microscopic theory shows that the zeroth Landau level is actually depleted by strong Auger scattering, ... Time-resolved optical pumping experiments reveal strong electron-electron scattering resulting in an Auger-depleted zeroth ... Ultrasensitive Photoresponse of Graphene Quantum Dots in the Coulomb Blockade Regime to THz Radiation *Elisa Riccardi ... Carrier dynamics in Landau-quantized graphene featuring strong Auger scattering. *Martin Mittendorff. 1,2. nAff9, ...
These Drape Armour radiation scatter drapes are designed to protect at the procedure site where scatter radiation is most ... Radiation Scatter Drapes. You are here: Home / Cardiac Intervention / Solutions / Procedural Trays, Packs & Kits / Radiation ... These Drape Armour® free positional shields are designed to protect at the procedure site where scatter radiation is most ...
Rayleigh scattering of sunlight in Earths atmosphere causes diffuse sky radiation, which is the reason for the blue color of ... In this case, the Rayleigh scattering intensity for a single particle is given in CGS-units by[16] I. =. I. 0. 8. π. 4. α. 2. λ ... The particle, therefore, becomes a small radiating dipole whose radiation we see as scattered light. The particles may be ... Rayleigh scattering applies to the case when the scattering particle is very small (x ≪ 1, with a particle size , 1 /10 ...
RADPAD® Absorbs Scatter Radiation. RADPAD® Radiation Protection Shields are used by physicians and cath lab personnel during ... Scatter radiation is secondary radiation that deflects from an object, most commonly the patient, during procedures, and can ... Scatter Radiation is Unavoidable, Physician Protection is Not. Posted on November 27, 2017 by RADPAD in Products, Safety with ... Scatter Radiation is Unavoidable, Physician Protection is Not * RADPAD Presents: Using the Venous System to Re-Vascularize ...
Scattering Assay.. Pancreatic cancer cells were plated at a density of 250 cells/well in DMEM containing 10% FBS into 6-well ... In this respect, current radiation strategies (especially the setting of target radiation field) need to be carefully ... Radiation.. Cells were irradiated with a dose of 5 or 10 Gy at room temperature using a 137Cs source (Gamma Cell 40; Atomic ... For example, radiation to the tumor bed stroma enhances the metastatic spread of carcinomas and sarcomas in mice (45) . It has ...
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; CYLINDRICAL CONFIGURATION; DIFFRACTION; DIFFUSION; ELECTROMAGNETIC RADIATION; ... ETDEWEB / Search Results / Scattering of electromagnetic waves by an non-uniform cylindrical plasma; Diffusion coherente dune ... Scattering of electromagnetic waves by an non-uniform cylindrical plasma; Diffusion coherente dune onde electromagnetique par ... "Scattering of electromagnetic waves by an non-uniform cylindrical plasma; Diffusion coherente dune onde electromagnetique par ...
The invention is directed to a grid used in x-ray imaging applications to block scattered radiation while allowing the desired ... a means for directing the ionizing radiation through a subject receiving region; a means for receiving radiation that has ... A small pore size is used and the grid has a thickness chosen to provide high scatter rejection. Formore » example, the grid ... The glass is arranged in a pattern so that a large fraction of the area is open allowing the imaging radiation to pass through ...
  • We present x-ray-diffraction, infrared reflectivity, and Raman-scattering measurements of La1.2(Sr1.8-xCax)Mn2O7 as a function of temperature and doping (x=0.0, 0.4, 0.6, and 0.8). (
  • It has been recently reported that data collection wavelengths in the range of λ = 1.5 − 3.0 Å are fairly easy to handle in a diffraction experiment and even at home sources using instant Cr Kα radiation [20]. (
  • [4] In 1922, Indian physicist C. V. Raman published his work on the "Molecular Diffraction of Light", the first of a series of investigations with his collaborators that ultimately led to his discovery (on 28 February 1928) of the radiation effect that bears his name. (
  • MRSEC has funded within the Department of Polymer Science and Engineering an X-Ray Facility with several modern instruments for x-ray scattering (small, intermediate and wide angles), powder x-ray diffraction, and x-ray reflectivity studies of thin films. (
  • GISAS combines the accessible length scales of small-angle scattering (SAS: SAXS or SANS) and the surface sensitivity of grazing incidence diffraction (GID). (
  • As a hybrid technique, GISAS combines concepts from transmission small-angle scattering (SAS), from grazing-incidence diffraction (GID), and from diffuse reflectometry. (
  • The Scattering of Light and other Electromagnetic Radiation covers the theory of electromagnetic scattering and its practical applications to light scattering. (
  • Electromagnetic radiation is emitted by the vibrational and collective modes of an opaque solid as the result of impulsive stimulated Raman scattering. (
  • Integral equation solution to the scattering of electromagnetic radiation by a linear chain of interacting triaxial dielectric ellipsoids. (
  • Rayleigh scattering ( / ˈ r eɪ l i / RAY -lee ), named after the nineteenth-century British physicist Lord Rayleigh (John William Strutt), [1] is the predominantly elastic scattering of light or other electromagnetic radiation by particles much smaller than the wavelength of the radiation. (
  • Electromagnetics is most familiar as light, or electromagnetic radiation. (
  • Its exchange particle is the photon (symbol γ) and the many forms of electromagnetic radiation are a manifestation of this interaction. (
  • Electromagnetic radiation interacts strongly with electrons. (
  • Describe experimental evidence to demonstrate the particle properties of electromagnetic radiation (photoelectric effect and Compton's experiments) and the wave properties of particles (Davisson and Germer experiment). (
  • where E is the energy of the incoming photon, m is the rest mass of the electron and c, the velocity of electromagnetic radiation. (
  • One type is electromagnetic radiation , which consists of wave motion of electric and magnetic fields. (
  • The quantum theory is based on the fact that electromagnetic waves consist of discrete "packets" of electromagnetic radiation, called photons , which have neither mass nor charge and have an energy inversely proportional to the wavelength of the wave. (
  • I am lookin for references to the electromagnetic radiation hazards that operators of MPI are exposed to. (
  • The ultraviolet (UV) radiative transfer problem in the martian atmosphere is dominated by multiple scattering of photons with the micron-sized aerosols that are suspended in the thin atmosphere. (
  • In the recent years, RIXS has been progressing very quickly in terms of energy resolution and understanding of the experimental results, but the interpretation of spectra could further improve, sometimes decisively, from a full knowledge of the polarization of incident and scattered photons. (
  • Raman scattering or the Raman effect ( / ˈ r ɑː m ən / ) is the inelastic scattering of photons by matter, meaning that there is both an exchange of energy and a change in the light's direction. (
  • When photons are scattered , most of them are elastically scattered ( Rayleigh scattering ), such that the scattered photons have the same energy ( frequency , wavelength and color) as the incident photons but different direction. (
  • An even smaller fraction of the scattered photons (approximately 1 in 10 million) can be scattered inelastically , with the scattered photons having an energy different (usually lower) from those of the incident photons-these are Raman scattered photons. (
  • 3. The photon counting type X-ray computed tomography apparatus according to claim 2, wherein the simulation performing unit sets a threshold to energy of the X-ray photons in the simulation of scattered radiation. (
  • The scattered probe is either photons (grazing-incidence small-angle X-ray scattering, GISAXS) or neutrons (grazing-incidence small-angle neutron scattering, GISANS). (
  • We show that due to the fact that the distributions of absorbing (ozone) and scattering (aerosols) agents are vertically coincident, the probability to absorb a photon following a multiple scattered trajectory is increased. (
  • The fundamental photon and charged particle interaction data and the radiation transport methods, pioneered and developed at NIST to calculate the penetration. (
  • If a photon encounters an electron, there is a high probability that a scattering interaction will occur. (
  • Fig. 3.2: The Compton Effect - (a) photon scattering and electron ejection leading to (b) an ionized atom. (
  • Cardiac morbidity and mortality have occurred more often in women with left-sided breast cancers [ 5 , 6 ], presumably because of excess radiation dose to the heart via tangential photon beams. (
  • Breath-hold techniques for photon radiation therapy can decrease cardiac exposure [ 7 , 8 ]. (
  • It is unlikely that further improvements in the delivery of photon-based radiation therapy can accomplish both goals of increasing coverage of regional nodes (particularly IMNs) and decreasing exposure to the heart and lung [ 12 ]. (
  • and a unit that produces data before reconstruction on the basis of the detected X-ray photon which corresponds to the second energy region, corrects and processes the data before reconstruction with the scattered photon distribution so as to produce corrected data, and reconstructs an image corresponding to the second energy region for which scattered radiation is corrected. (
  • Availability of synchrotron radiation, cryo-crystallography and improved software for heavy atom location and density modification have increased the ability to solve protein structures using SAD. (
  • In the absence of synchrotron radiation, SAD method using rotating anode generator (Cu Kα and Cr Kα) lab source data is mostly used to solve the phase problem in X-ray crystallography. (
  • Synchrotron radiation facilities are pillars of modern structural biology. (
  • book characterization of polymers in the solid state ii synchrotron radiation x ray scattering from United States to let this maximum. (
  • Synchrotron radiation is very useful for various fields in both basic and applied research. (
  • Stop Træt i søg online , hvor Få Download roman Characterization of Polymers in the Solid State II: Synchrotron Radiation, X-ray Scattering and Electron Microscopy, du kan finde alle du kan. (
  • I vores resource vil finde dette E-ebook Characterization of Polymers in the Solid State II: Synchrotron Radiation, X-ray Scattering and Electron Microscopy, sammen med ebooks forbundet karakteristiske generos fra Illusion , og private investigator at nogle slags elsker Historie. (
  • Nyttig ressource er ægte kendte ikke mangel af af Marketing, en let kan læse hans ebook Characterization of Polymers in the Solid State II: Synchrotron Radiation, X-ray Scattering and Electron Microscopy stille. (
  • Snart efter Adgang, de e-ebooks Characterization of Polymers in the Solid State II: Synchrotron Radiation, X-ray Scattering and Electron Microscopy kan omskrevet hans en favorit alt fil, rtf, epub, dokument, fb2, for at se mobi Format du skal bare læse alle mens at rejse, foruden asi cross kedeligt tur. (
  • Ophold os, at lære imponerende Ebook Characterization of Polymers in the Solid State II: Synchrotron Radiation, X-ray Scattering and Electron Microscopy liv lidt daglige liv. (
  • These projects often involve travel to undertake experiments on national or international synchrotron radiation sources. (
  • I also teach courses at synchrotron radiation summer schools both at Diamond and Internationally. (
  • Low energy excitations such as magnon, plaron and phonon are primary properties tightly associated with unique physical phenomena of materials and can be probed by powerful inelastic neutron scattering usually in bulk crystal. (
  • In this study, we have used an inelastic neutron scattering on SrRuO3 thin films to investigate the magnon dispersion curve in this ferromagnetic system to better understand the underlying mechanisms. (
  • This is the first report to prove the existence of magnons in SrRuO2 system using an inelastic neutron scattering experiment on a thin film systems. (
  • X-ray and neutron-scattering techniques characterize proteins in solution and complement high-resolution structural studies. (
  • X-ray and neutron-constrained scattering modelling as an additional means to determine structures form the focus of this review. (
  • The first overall views of many protein structures have been obtained by X-ray or neutron scattering. (
  • We have an EPSRC research grant for soft x-ray and neutron scattering studies of nanoscale ordering in strongly correlated electron systems.We designed and constructed an advanced diffractometer for resonant soft X-ray scattering for use on the new national synchrotron Diamond. (
  • Gamma radiation is detected, and in some cases complemented by neutron detection when sensitivity for nuclear material is desired. (
  • Utilizing recoil nuclei following neutron scatter events, natural helium glows (scintillates), allowing photomultipliers (e.g. (
  • Raman scattering of near-infrared femtosecond laser pulses produces coherent longitudinal optical phonon and plasmon oscillations in the semiconductor InSb. (
  • The THz spectra exhibit features consistent with Raman selection rules including interference of allowed and forbidden Raman scattering. (
  • Stimulated Raman scattering of a laser in a plasma with clusters. (
  • A high intensity laser propagating through such a plasma undergoes stimulated Raman scattering (SRS). (
  • Surface optical phonon and A1(LO) in ZnO submicron crystals probed by Raman scattering: Effects of morphology and dielectric coating. (
  • The authors studied the surface optical phonon and A1(LO) in ZnO submicron crystals as well as ZnO single crystals with submicron surface structures by employing ultraviolet Raman scattering. (
  • Raman scattering is used to investigate the room temperature phonons of tetragonal (I4/m) Sr2CoWO6 and monoclinic (P21/n) Ca2CoWO6, Sr2CoTeO6, and Ca2CoTeO6 double perovskites. (
  • Deep ultraviolet Raman scattering characterization of ion-implanted SiC crystals. (
  • Determination of free carrier density in the low doping regime of 4H-SiC by Raman scattering. (
  • Rayleigh scattering of sunlight in Earth's atmosphere causes diffuse sky radiation , which is the reason for the blue color of the daytime and twilight sky , as well as the yellowish to reddish hue of the low Sun . Sunlight is also subject to Raman scattering , which changes the rotational state of the molecules and gives rise to polarization effects. (
  • This is called normal Stokes Raman scattering. (
  • The inelastic scattering of light was predicted by Adolf Smekal in 1923 [3] and in older German-language literature it has been referred to as the Smekal-Raman-Effekt. (
  • Raman received the Nobel Prize in 1930 for his work on the scattering of light. (
  • [10] Early spectra took hours or even days to acquire due to weak light sources, poor sensitivity of the detectors and the weak Raman scattering cross-sections of most materials. (
  • The following focuses on the theory of normal (non-resonant, spontaneous, vibrational) Raman scattering of light by discrete molecules. (
  • Raman scattering generally gives information about vibrations within a molecule. (
  • The basics of infrared absorption regarding molecular vibrations apply to Raman scattering although the selection rules are different. (
  • The evaluation of PASSSA in radiographic mode through simulations and experiments revealed noteworthy results both in terms of image contrast improvement and scatter induced bias reduction. (
  • The use of chromium-anode X-ray radiation is very useful for SAD experiments. (
  • In 1859, while attempting to determine whether any contaminants remained in the purified air he used for infrared experiments, John Tyndall discovered that bright light scattering off nanoscopic particulates was faintly blue-tinted. (
  • Inelastic scattering experiments were carried out in ANSTO SIKA and NIST SPINS. (
  • These so-called fluctuation X-ray scattering experiments can be performed on modern synchrotrons ( 7 ) and free electron laser sources ( 8 , 9 ). (
  • The angular correlation information provided from these experiments is directly related to the imaged structure ( 10 ) and contains significantly more information than standard small- and wide-angle X-ray scattering (SAXS/WAXS) data. (
  • In combination with the straightforward scattering geometry, where all relevant information is contained in a single scattering image, in-situ and real-time experiments are facilitated. (
  • The elastic light scattering phenomena called Rayleigh scattering, in which light retains its energy, was described in the 19th century. (
  • [2] In 1908, another form of elastic scattering, called Mie scattering was discovered. (
  • We present a method based on multiple-scattering to determine elastic cross sections for electron collisions with molecular clusters. (
  • Availability of in-house lab data collection sources (Cu Kα and Cr Kα radiation), cryo-crystallography and improved software for heavy atom location and density modification have increased the ability to solve protein structures using SAD. (
  • In distinction to scattering, crystallography provides atomic-resolution detail for a broad range of macromolecules of all sizes, while NMR does so for smaller macromolecules. (
  • Each voxel is modelled as having scattering and attenuation properties, represented by numerical coefficients. (
  • The system computes the intensity of radiation that would emerge from the object at the exit points if the interior of the object were characterized by a currently assigned set of values for the scattering and attenuation coefficients. (
  • The final values of the scattering and attenuation coefficients from this process are mapped so as to generate a series of images of the interior of the object depicting the attenuation and scattering characteristcs of the object's interior. (
  • If the measurement is performed at a plurality of wavelenghts on an object to be measured, a ratio of absorption coefficients and a ratio of concentrations of specified absorptive constituents in scattering medium can be measured. (
  • 2. A method of measuring a scattering medium according to claim 1, wherein said extracting step includes selecting internal information from the group consisting of the effective attenuation coefficients, μ effj , and a ratio of the absorption coefficients, μ aj . (
  • 4. A method of measuring a scattering medium according to claim 3, wherein said extracting step includes extracting internal information including a ratio of the absorption coefficients, μ aj , with respect to the wavelengths of said light, and a ratio of concentrations of the specified absorptive constituents in the scattering medium. (
  • From the analysis of the obtained spectra, a simple empirical power law equation is found that relates absorbance with scattering and absorption coefficients. (
  • The dependence of the optical path length on the absorption and scattering coefficients is also analyzed, and estimations of this parameter for physiological conditions are presented. (
  • Some active research lines in this matter are: the estimation of the optical path length, 5 the look-ahead distance or the area under study, 6 the comparison of different algorithms to measure oxygen saturation, 1 the determination of scattering and absorption coefficients, 7 , 8 or the simulation of light propagation in tissue using Monte Carlo methods. (
  • said photodetection means comprising a rotatable optical means comprising a first reflecting means and a second reflecting means whose optical axis is nearly coincident with the optical axis of said first reflecting means, whereby said elastically-scattered light is concentrated to facilitate detection thereof, said first reflecting means located to receive said elastically-scattered light and said second reflecting means located to receive light reflected from said first reflecting means. (
  • The simultaneous measurement of energy and linear polarization of the scattered radiation in resonant inelastic soft x-ray scattering. (
  • article{Braicovich2014TheSM, title={The simultaneous measurement of energy and linear polarization of the scattered radiation in resonant inelastic soft x-ray scattering. (
  • Resonant Inelastic X-ray Scattering (RIXS) in the soft x-ray range is an element-specific energy-loss spectroscopy used to probe the electronic and magnetic excitations in strongly correlated solids. (
  • Resonant inelastic X-ray scattering (RIXS) probes various excitations in materials, including plasmons, magnons and phonons. (
  • H. Ding, G. Chen, A. K. Majumdar, B. M. Sadler, and Z. Xu, "Modeling of non-line-of-sight ultraviolet scattering channels for communication," IEEE J. Selec. (
  • The anomalous scattering signal is more than doubled for various metals when compared to conventional copper characteristic wavelength. (
  • For light frequencies well below the resonance frequency of the scattering particle (normal dispersion regime), the amount of scattering is inversely proportional to the fourth power of the wavelength. (
  • Scattering by particles similar to, or larger than, the wavelength of light is typically treated by the Mie theory , the discrete dipole approximation and other computational techniques. (
  • where r is the particle's radius, λ is the wavelength of the light and x is a dimensionless parameter that characterizes the particle's interaction with the incident radiation such that: Objects with x ≫ 1 act as geometric shapes, scattering light according to their projected area. (
  • Yes or No, Violet astronomy is the radiation astronomy over the wavelength band 380-450 nm. (
  • Radiation with enough energy to knock electrons out of atoms and produce ions is called ionizing radiation and includes alpha particles, beta particles, x-rays, and gamma rays. (
  • The measuring technique is based on simultaneous observation of transmitted and scattered light fluxes in growing aerosol droplets. (
  • We include the latest SPICAM measurements on the aerosol vertical profile (distribution of Angstrom exponent and aerosol loading), scattering properties (asymmetry parameter and single scattering albedo), ground albedo, and O3 content as well as MER long-term monitorization of ground-based aerosol optical depth. (
  • Sur la base de cette analyse du diffusé, une approche originale dite « Partial Attenuation Spectral Scatter Spectral Atténuation » (PASSSA) adaptée à l'imagerie multi-énergies a été développée. (
  • Based on the conducted scatter analysis, a Partial Attenuation Spectral Scatter Separation Approach (PASSSA) adapted for multi-energy imaging was developed. (
  • The aim is to determine the concentration of optically absorbing substances (chromophores) from the attenuation of the incident light, taking into account the scattering of the tissue. (
  • The attenuation of X-rays by materials used for radiation detection has been discussed in an earlier chapter . (
  • Feedback measurement of axial scattering force. (
  • Until now, measurement of diffuse scattering from protein crystals has been scarce because of the extra effort of collecting diffuse data. (
  • Basic DC and AC circuits including capacitors and inductors and their applications in radiation measurement equipment and chemical process parameter measurements. (
  • It was found that Monte Carlo results were in good agreement with the experimental data, whereas the small angle approximation considerably underestimated the multiple scattering contributions to the transmitted light for our experimental conditions. (
  • Small-Angle X-ray scattering performed at synchrotron sources is often used to characterize the shape of biological macromolecules. (
  • The situation is somewhat similar to a billiard-ball collision and we use the angle, θ, to express the extent of the scattering process. (
  • The angle, θ, can be in any direction, although it is found that there is a preference for scatter in the forwards direction at higher X-ray energies. (
  • Fluctuation X-ray scattering is an emerging imaging technique that seeks to overcome the low data-to-parameter ratio encountered in traditional small- and wide-angle X-ray scattering methods. (
  • Fluctuation X-ray scattering (FXS) is an extension of small- and wide-angle X-ray scattering in which the X-ray snapshots are taken below rotational diffusion times. (
  • Grazing-incidence small-angle scattering (GISAS) is a scattering technique used to study nanostructured surfaces and thin films. (
  • With diffuse (off-specular) reflectometry it shares phenomena like the Yoneda/Vinyard peak at the critical angle of the sample, and the scattering theory, the distorted wave Born approximation (DWBA). (
  • In the interpretation of GISAS images some complication arises in the scattering from low-Z films e.g. organic materials on silicon wafers, when the incident angle is in between the critical angles of the film and the substrate. (
  • By employing atomic force microscopy, another common technique to determine the shape of biological macromolecules when deposited on flat substrates, we present a protocol to evaluate and characterize consequences of radiation damage. (
  • Absorption and scattering processes in biological tissues are studied through reflectance spectroscopy in tissue-like phantoms. (
  • This study is useful to better understand the scattering phenomena in biological tissue, and to obtain absolute concentration of absorber particles when a homogeneous medium can be assumed. (
  • Physical and biological aspects of the interaction of the radiation with the patient's anatomy are addressed in this chapter. (
  • Nuclear reactions, decay, interactions of physical radiation with matter, methods of radiation detection and biological effects of radiation, external and internal dosimetry. (
  • Although solution scattering has been applied successfully to many problems in the biological sciences ( 2 , 3 ), the technique suffers from a significant shortcoming. (
  • These topics are followed by discussions on the application of light scattering to the determination of the size distribution of colloidal particles. (
  • These chapters also describe the effect upon light scattering of partial orientation of anisotropic particles in electrical and magnetic fields and in viscous flow. (
  • The present invention relates generally to systems which produce images of the interior of an object and particularly to methods and systems for imaging the interior of an object using scattered radiation or scattered particles. (
  • Rayleigh scattering results from the electric polarizability of the particles. (
  • Rayleigh scattering applies to particles that are small with respect to wavelengths of light, and that are optically "soft" (i.e., with a refractive index close to 1). (
  • Rutherford scattering showed that the electromagnetic field has a greater range than the weak or strong fields and charged particles usually interact electromagnetically before other fields have a chance to operate. (
  • We introduce a phase-control holographic technique to characterize scattering media with the purpose of focusing light through it. (
  • The precipitable water depth and the scattered irradiance intensity were measured at the Atmospheric Physics Laboratory of the University of Patras during sunny days, at constant solar elevations, in the time period 2006-2009, exhibiting seasonal variation with a summer maximum and a winter minimum. (
  • Two families of regression curves of the scattered irradiance intensity with precipitable water depth are being obtained, one for continental and one for maritime air masses. (
  • The aim of this work is the computation of the scattered irradiance intensity from the origin of the air masses, and the values of the precipitable water depth and relative atmospheric mass. (
  • Panagiotopoulou M.D., Rapti A.S., Panagiotopoulos N.D. (2013) Regression of the Scattered Radiation Intensity with Precipitable Water Depth and Relative Atmospheric Mass. In: Helmis C., Nastos P. (eds) Advances in Meteorology, Climatology and Atmospheric Physics. (
  • [3] He conjectured that a similar scattering of sunlight gave the sky its blue hue , but he could not explain the preference for blue light, nor could atmospheric dust explain the intensity of the sky's color. (
  • Rayleigh scattering usually has an intensity in the range 0.1% to 0.01% relative to that of a radiation source. (
  • The intensity of Rayleigh scattering is about 10 −3 to 10 −4 compared to the intensity of the exciting source. (
  • The average intensity of forward light scatter and perpendicular light scatter signals was demonstrated to increase as cells became less well-differentiated. (
  • From GID it uses the scattering geometry close to the critical angles of substrate and film, and the two-dimensional character of the scattering, giving rise to diffuse rods of scattering intensity perpendicular to the surface. (
  • These complications are often more than offset by the fact that the dynamic enhancement of the scattering intensity is significant. (
  • Light has a certain probability of being scattered by a material. (
  • As part of the NIST on a Chip program, the Photonic Dosimetry project is set to develop in-situ sub-micrometer ionizing-radiation dosimetry and calorimetry. (
  • Check standards are used by the NIST Ionizing Radiation Division to monitor the performance of the alanine dosimetry system that is central to its high-dose. (
  • Concentrating on the underlying principles of radiation physics, it covers the prerequisite knowledge for medical physics courses on the graduate and post-graduate levels in radiotherapy physics, radiation dosimetry, imaging physics, and health physics, thus providing the link between elementary physics on the one hand and the intricacies of the medical physics specialties on the other hand. (
  • Others training for professions that deal with ionizing radiation in diagnosis and treatment as well as medical residents, students of technology and dosimetry,and biomedical engineering will find many sections interesting and useful for their studies. (
  • It covers the prerequisite knowledge needed for courses specific to the subdisciplines of medical physics----------------radiotherapy physics, radiation dosimetry, imaging physics----, and health physics. (
  • A new, comprehensively updated edition of the acclaimed textbook by F.H. Attix (Introduction to Radiological Physics and Radiation Dosimetry) taking into account the substantial developments in dosimetry since its first edition. (
  • The four authors continuing the pioneering work of Frank Attix, Prof Pedro Andreo (Karolinska, Stockholm), Dr David T. Burns (BIPM, Paris), Prof Alan E. Nahum (University of Liverpool) and Prof Jan Seuntjens (McGill University, Montreal), are leading scientists in radiation dosimetry, having published between them more than 600 papers in the field. (
  • Our purpose is to develop an understanding of the mechanisms and consequences of the absorption and scattering of radiant energy in the image formation process and in radiation dosimetry. (
  • Furthermore, naturally bound metals and atoms from crystallization solutions tend to show a significant increase in anomalous scattering with chromium radiation [21,22]. (
  • Scattering force on atoms. (
  • Saturation of the scattering force on atoms. (
  • The possibilities are proposed of imaging of highly scattering objects based on the measurements of correlation characteristics of the spectrum of scattered radiation. (
  • To assess the scattered radiation dose to personnel during CT fluoroscopy using phantom measurements. (
  • The goal of this study is to develop a more appropriate shielding calculation method for computed tomography (CT) in comparison with the Japanese conventional (JC) method and the National Council on Radiation Protection and Measurements (NCRP)-dose length product (DLP) method. (
  • 1996. Parameterization for the absorption of solar radiation by water vapor and ozone. (
  • 1974. A parameterization for the absorption of solar radiation in the earth's atmosphere. (
  • 2000. Parameterization of the scattering and absorption properties of individual ice crystals. (
  • A method of measuring internal information in a scattering medium and an apparatus for the same of the present invention measure internal information in the scattering medium by measuring light diffused during propagation in the scattering medium at outside of the scattering medium while receiving the influence of the scattering and absorption, and performing arithmetic processing to the measured values. (
  • The application of perpendicular and forward light scatter to assess nuclear and cellular morphology. (
  • Perpendicular light scatter has been shown to correlate with nuclear size and shape. (
  • This well-received textbook and reference summarizes the basic knowledge of atomic, nuclear, and radiation physics that professionals working in medical physics and biomedical engineering need for efficient and safe use of ionizing radiation. (
  • Preparations for the mammoth task of decommissioning crippled reactors at the Fukushima No. 1 nuclear power plant are being stymied by continued high levels of radiation from the triple meltdowns there two years ago. (
  • We have yet to identify all hotspots, where radiation levels are locally high," [Atsuhiko Kosaka, chief of the Nuclear Regulation Office responsible for the Fukushima No. 1 plant] said. (
  • Radiation interaction with matter and detection techniques for nuclear radiations. (
  • radiation quantities, macroscopic behaviour and the characterization of radiation fields and beams are covered in detail. (
  • At the intermediate x ≃ 1 of Mie scattering , interference effects develop through phase variations over the object's surface. (
  • This as well as interference between the scattering from the direct and the reflected beam can be fully accounted for by the DWBA scattering theory. (
  • These devices, having better energy resolution than PVT, were supposed to reduce nuisance alarm rates by distinguishing threats from benign sources on the basis of the detected gamma radiation spectra. (
  • This paper presents two conclusions concerning the scattered light distribution method for particle sizing: (1) a large difference in vector values is one of the primary causes of an ill-conditioned kernel matrix, and (2) under narrow band and high resolution particle size conditions, the forward scattering region would introduce a larger error into the particle size distribution. (
  • However, while diffuse reflectivity remains confined to the incident plane (the plane given by the incident beam and the surface normal), GISAS explores the whole scattering from the surface in all directions, typically utilizing an area detector. (
  • In this case, the reflected beam from the substrate has a similar strength as the incident beam and thus the scattering from the reflected beam from the film structure can give rise to a doubling of scattering features in the perpendicular direction. (
  • To realize this potential, both Bragg scattering, which is currently used to derive macromolecular structures, and diffuse scattering, which reports on correlations in charge density variations, must be measured. (
  • Perpendicular and forward light scatter have been employed in a multiparametric approach to distinguish the various lines of the transplantable Dunning R3327 rat prostatic adenocarcinoma. (
  • The combination of perpendicular and forward light scatter allows for the discrimination of histologically indistinguishable tumors and may therefore be useful to establish a system of grading cancer. (
  • The refraction correction applies to the perpendicular component of the scattering vector with respect to the substrate while the parallel component is unaffected. (
  • Thus parallel scattering can often be interpreted within the kinematic theory of SAS, while refractive corrections apply to the scattering along perpendicular cuts of the scattering image, for instance along a scattering rod. (
  • Anomalous scattering methods are currently widely used for phasing macromolecular structures [8]. (
  • In this report, we demonstrate that synchrotron x-ray scattering methods offer the possibility of improving our fundamental understanding of RO materials. (
  • These data suggest that methods for delivering radiation therapy that minimize cardiac and pulmonary radiation doses will increase the therapeutic ratio of radiation therapy, further positively affecting overall survival. (
  • Our results show that using diffuse scattering to model protein motions can become a component of routine crystallographic analysis through the extension of commonplace methods. (
  • For both of these, constrained scattering modelling methods are essential. (
  • The radiation doses were calculated for the same period using the JC and NCRP-DLP methods. (
  • By acquiring a large number of ultrashort X-ray exposures on an ensemble of molecules, this technique produces a dataset that contains structural information far beyond what is obtainable from traditional solution scattering methods without requiring crystallization. (
  • This technique, performed using a free electron laser or ultrabright synchrotron source, provides significantly more experimental information compared with traditional solution scattering methods. (
  • Radiation damage on the globular enzyme leads to an apparent increase in molecular sizes whereas the effect on the long virus is a breakage into smaller pieces resulting in a decrease of the average long-axis radius. (
  • The two strengths of solution scattering are (i) the ability to produce molecular structures when crystals cannot be obtained (although only at medium structural resolution) and (ii) the validation of protein crystal structures in solution. (
  • Using data at the lowest scattering angles, Guinier plots of ln I ( Q ) versus Q 2 lead to the molecular weight from the I (0) parameter at zero Q and the radius of gyration R G . Linearity of the Guinier plots establishes the monodispersity of the macromolecule. (
  • In this article, we introduce a flexible iterative method that can rapidly determine molecular structure from fluctuation scattering data. (
  • Although the relation from real space structure to fluctuation scattering data is straightforward, the inverse problem of determining a molecular model from fluctuation scattering data is nontrivial ( 8 ). (
  • The last chapters are devoted to the Rayleigh-Debye scattering and the scattering by liquids, as well as the concept of anisotropy. (
  • Rayleigh scattering causes the blue color of the daytime sky and the reddening of the Sun at sunset . (
  • Earlier work attempting to determine 3D shape from fluctuation scattering data was based on solving two phase problems consecutively. (
  • Figure 1: Pump-probe spectroscopy on graphene with linearly polarized radiation. (
  • Zuo Haoyi, Ma Qian, and Luo Shirong, "Discussion concerning ill-conditioned kernel matrices when retrieving particle size distributions based on scattered radiation distribution," J. Opt. (
  • Scattered dose distributions were measured in a CT room with 18 scanners (16 scanners in the case of the JC method) for one week during routine clinical use. (
  • The parameterization of UV radiation by cloud ice crystal was applied to solar radiation model and the sensitivity of this model for the variation of ice crystal was tested. (
  • CHICAGO, Nov. 27, 2012 /PRNewswire-USNewswire/ -- The radiation dose to areas of the body near the breast during mammography is negligible, or very low, and does not result in an increased risk of cancer, according to a study presented today at the annual meeting of the Radiological Society of North America (RSNA). (
  • To better understand the potential impact of scatter radiation, Dr. Chetlen and colleagues set out to measure the dose received by the thyroid gland, salivary gland, sternum, uterus and the lens of the eye during screening digital mammography. (
  • Each of the 207 women in the study group wore six optically stimulated luminescent dosimeters -- a device used to measure an absorbed dose of ionizing radiation -- while undergoing two-view screening mammography. (
  • Absorbed radiation dose is measured in a unit called a milligray (mGy). (
  • In fact, all areas except for the sternum received less than 2 percent of annual background radiation dose. (
  • Based on the extremely low scatter radiation dose to the thyroid -- equivalent to just a few minutes of background radiation -- thyroid shields are unnecessary during mammography. (
  • In addition, the researchers warn that use of thyroid shields could result in an increased radiation dose to patients. (
  • A thyroid shield gets in the way of the exam and can actually cause an increase in radiation dose by necessitating repeat exams," Dr. Chetlen said. (
  • The effect of varying the phantom effective thickness on scattered radiation dose was also evaluated using a plain phantom. (
  • For each configuration, the scattered radiation dose at each applied tube potential was linearly related to the distance from the isocentre when the slice thickness and phantom effective thickness were constant. (
  • The results of this study (in the form of the linear equations obtained) enable the scattered radiation dose to be estimated based on the distance from the isocentre and kV setting of a particular CT scanner and scanning configuration, and can be used to develop guidelines for radiation protection management. (
  • The radiation dose to areas of the body near the breast during mammography is negligible, or very low, and does not result in an increased risk of cancer, according to a new study. (
  • The rationale for proton therapy in the treatment of breast cancer is reduced inadvertent radiation dose to the heart and lung, as well as improved target coverage. (
  • the absorbed dose depends both on the type of radiation and on the material in which it is absorbed. (
  • A major challenge with high-energy X-ray beam on such macromolecules is the perturbation of sample due to radiation damage. (
  • Langer, SG & Gray, JE 1998, ' Radiation shielding implications of computed tomography scatter exposure to the floor ', Health Physics , vol. 75, no. 2, pp. 193-196. (
  • for the theory of radiation physics at a fundamental level, Podgorsak's book provides a wonderful resource presented in a well organized and easy to learn manner, in a way not found in any other text. (
  • Which of the following are green radiation astronomy phenomena associated with the Sun? (
  • As a particular consequence of the DWBA, the refraction of x-rays or neutrons has to be always taken into account in the case of thin film studies, due to the fact that scattering angles are small, often less than 1 deg. (
  • This book is divided into 10 chapters that particularly present examples of practical applications to light scattering from colloidal and macromolecular systems. (
  • The particle, therefore, becomes a small radiating dipole whose radiation we see as scattered light. (
  • A method of measuring internal information in a scattering medium and an apparatus for the same of the present invention measure internal information in the scattering medium by measuring light diffused during propagation in the scattering medium at outside of the scattering medium while receiving the. (
  • Amphiphilic drug persuaded collapse of polyvinylpyrrolidone and poly(ethylene glycol) chains: a dynamic light scattering study. (
  • Light scattering has proved to be useful in characterizing colloidal systems. (
  • We have studied the interaction between an amphiphilic drug, amitriptyline hydrochloride (AMT), and neutral polymers, polyvinylpyrrolidone (PVP) and poly(ethylene glycol) (PEG), using the dynamic light scattering (DLS) technique. (
  • Widespread applications of dynamic light scattering techniques to the study of macromolecular Brownian motion have yielded not only a valuable store of factual information concerning solution conformations and conformational changes, but have also provided an important window through which to view the dynamics of internal modes of motion. (
  • The invention relies upon the detection of back scattered light from an evanescent wave disturbed by the presence of a colloidal gold label brought to the interface by an. (
  • Seven days after exposure, the lenses were macroscopically imaged and light scattering was quantitatively measured. (
  • The difference of light scattering in the lenses between exposed and contralateral not-exposed eyes was 0.00±0.02, 0.01±0.03 , −0.01±0.02 , and −0.01±0.03 transformed equivalent diazepam concentration (tEDC), respectively, and no apparent morphological changes in the lens were observed. (
  • The 3-axis motorized Dectris Pilatus detector, with 172 micron resolution and associated beam stop, delivers an unprecedented combination of low-noise, high dynamic range (very high maximum pixel count rate at 2 million counts per second per pixel), high spatial resolution, high detection efficiency at 8 keV, and extremely high resistance to radiation damage and deterioration. (
  • The results of the testing of radiation detection instruments with radionuclide identification capabilities will depended on the sources used for the tests. (
  • Radiation Portal Monitors (RPMs) are passive radiation detection devices used for the screening of individuals, vehicles, cargo or other vectors for detection of illicit sources such as at borders or secure facilities. (
  • A mathematical formalism describing plane electromagnetic wave scattering by a linear chain of N triaxial dielectric ellipsoids of complex index of refraction is presented. (
  • The problem of the scattering of plane electromagnetic waves from a non-uniform, cylindrically symmetrical plasma is solved analytically, by a self-consistent field method, for a wave with the electric field parallel to the cylinder axis. (
  • The damage mechanism for near-infrared radiation (IRR) induced cataract is unclear. (
  • 6 Wolbarsht advocated that near-infrared radiation cataract can be photochemically induced. (
  • Describe the Rutherford scattering experiment and perform simple calculations for the distance of closest approach between nuclei in a head-on collision. (
  • E. G. Kablukova, B. A. Kargin, A. A. Lisenko, G. G. Matvienko, and E. N. Chesnokov, "Numerical statistical simulation of terahertz radiation propagation in cloudiness," Opt. (
  • It is a radiation scattering event where the incoming X-ray gets scattered by an outer atomic electron - as illustrated in Figure 3.2. (
  • A study of breast-conserving therapy, with or without radiation to those nodal regions [ 4 ], has also demonstrated significant advantages in disease control with regional node irradiation. (
  • These results show that radiation damage can appear in different forms and strongly support the need to check the effect of radiation damage at synchrotron sources using the presented protocol. (
  • R.F. Egerton, Radiation damage to organic and inorganic specimens in the TEM . (
  • R.F. Egerton, Vibrational-loss EELS and the avoidance of radiation damage , Ultramicroscopy 159 (2015) 95-100. (
  • R.F. Egerton , P. Li and M. Malac , Radiation damage in the TEM and SEM . (
  • This kind of radiation can produce tissue damage directly by striking a vital molecule, such as DNA, or indirectly by striking a water molecule and producing highly reactive free radicals that chemically attack vital molecules. (
  • But exactly how does this kind of microwave radiation damage your health? (
  • Radiation Damage in Biomolecular Systems. (
  • We also demonstrate focusing through a temporally dynamic, strongly scattering sample with short speckle decorrelation times. (
  • X-ray scattering studies of strongly correlated electron systems such as transition metal oxides. (
  • Color astronomy is a lecture as part of the radiation astronomy department course development of principles of radiation astronomy . (
  • Most systems which produce images of the interior of an object, such as the human body, utilize in-line unscattered radiation, such as x-ray sources and detectors. (
  • This article investigates whether CT scanners used primarily for either head or body work have scattered radiation levels that may impact shielding considerations. (
  • An algorithm for the suppression of the radiation and scattering fields created by vibration of the smooth closed surface of a body of arbitrary shape placed in a liquid is designed and analytically explored. (
  • The purpose of this report is to provide a technical guide for the treatment of breast cancer with passive-scattering proton therapy and an algorithm for selecting patients with breast cancer who would benefit from proton therapy. (
  • We develop a multitiered iterative phasing algorithm to determine the underlying structure of the scattering object from FXS data. (
  • This analysis also proves that even the anomalous signal provided or present naturally in a macromolecule is good enough to solve crystal structures successfully using lab source chromium-generated X-ray radiation. (
  • X-ray solution scattering of macromolecular complexes is a versatile technique, providing low-resolution structural information that, when supplemented with high-resolution crystallographic data, can result in fundamental insights into the physiological behavior and function of macromolecular machines ( 1 ). (
  • The main aim of the present thesis was to develop a scatter correction approach adapted for multi-energy imaging. (
  • Additionally, simulation studies examined the performance of the developed approach in CT, where PASSSA also proved to be quite effective at correcting scatter induced distortions. (
  • An analysis based on a microscopic theory shows that the zeroth Landau level is actually depleted by strong Auger scattering, even though it is optically pumped at the same time. (