The property of nonisotropic media, such as crystals, whereby a single incident beam of light traverses the medium as two beams, each plane-polarized, the planes being at right angles to each other. (Cline et al., Dictionary of Visual Science, 4th ed)
Microscopy using polarized light in which phenomena due to the preferential orientation of optical properties with respect to the vibration plane of the polarized light are made visible and correlated parameters are made measurable.
An acid dye used in testing for hydrochloric acid in gastric contents. It is also used histologically to test for AMYLOIDOSIS.
Methods and procedures for the diagnosis of diseases of the eye or of vision disorders.
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.
A generic grouping for dihydric alcohols with the hydroxy groups (-OH) located on different carbon atoms. They are viscous liquids with high boiling points for their molecular weights.
A technique of diagnostic imaging of RETINA or CORNEA of the human eye involving the measurement and interpretation of polarizing ELECTROMAGNETIC WAVES such as radio or light waves. It is helpful in the diagnosis of GLAUCOMA; MACULAR DEGENERATION; and other retinal disorders.
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).
Slender processes of NEURONS, including the AXONS and their glial envelopes (MYELIN SHEATH). Nerve fibers conduct nerve impulses to and from the CENTRAL NERVOUS SYSTEM.
An organization of cells into an organ-like structure. Organoids can be generated in culture. They are also found in certain neoplasms.
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.
An order of the class Insecta. Wings, when present, number two and distinguish Diptera from other so-called flies, while the halteres, or reduced hindwings, separate Diptera from other insects with one pair of wings. The order includes the families Calliphoridae, Oestridae, Phoridae, SARCOPHAGIDAE, Scatophagidae, Sciaridae, SIMULIIDAE, Tabanidae, Therevidae, Trypetidae, CERATOPOGONIDAE; CHIRONOMIDAE; CULICIDAE; DROSOPHILIDAE; GLOSSINIDAE; MUSCIDAE; TEPHRITIDAE; and PSYCHODIDAE. The larval form of Diptera species are called maggots (see LARVA).
An imaging method using LASERS that is used for mapping subsurface structure. When a reflective site in the sample is at the same optical path length (coherence) as the reference mirror, the detector observes interference fringes.
A phylum of the most familiar marine invertebrates. Its class Stelleroidea contains two subclasses, the Asteroidea (the STARFISH or sea stars) and the Ophiuroidea (the brittle stars, also called basket stars and serpent stars). There are 1500 described species of STARFISH found throughout the world. The second class, Echinoidea, contains about 950 species of SEA URCHINS, heart urchins, and sand dollars. A third class, Holothuroidea, comprises about 900 echinoderms known as SEA CUCUMBERS. Echinoderms are used extensively in biological research. (From Barnes, Invertebrate Zoology, 5th ed, pp773-826)
Materials in intermediate state between solid and liquid.
Thin strands of transparent material, usually glass, that are used for transmitting light waves over long distances.
The deductive study of shape, quantity, and dependence. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)
The visual display of data in a man-machine system. An example is when data is called from the computer and transmitted to a CATHODE RAY TUBE DISPLAY or LIQUID CRYSTAL display.
The extraction and recovery of usable or valuable material from scrap or other discarded materials. (from McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed.)
A vacuum tube equipped with an electron emitting CATHODE and a fluorescent screen which emits visible light when excited by the cathode ray. Cathode ray tubes are used as imaging devises for TELEVISIONS; COMPUTER TERMINALS; TEXT TELECOMMUNICATION DEVICES; oscilloscopes; and other DATA DISPLAY devices.
Compounds formed by the joining of smaller, usually repeating, units linked by covalent bonds. These compounds often form large macromolecules (e.g., BIOPOLYMERS; PLASTICS).
The free-swimming larval forms of parasites found in an intermediate host.
The visually perceived property of objects created by absorption or reflection of specific wavelengths of light.
The determination of the pattern of genes expressed at the level of GENETIC TRANSCRIPTION, under specific circumstances or in a specific cell.
The formation of crystalline substances from solutions or melts. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
Products or parts of products used to detect, manipulate, or analyze light, such as LENSES, refractors, mirrors, filters, prisms, and OPTICAL FIBERS.
Methods of creating machines and devices.
Ultrasonography applying the Doppler effect, with frequency-shifted ultrasound reflections produced by moving targets (usually red blood cells) in the bloodstream along the ultrasound axis in direct proportion to the velocity of movement of the targets, to determine both direction and velocity of blood flow. (Stedman, 25th ed)
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
Any of a variety of procedures which use biomolecular probes to measure the presence or concentration of biological molecules, biological structures, microorganisms, etc., by translating a biochemical interaction at the probe surface into a quantifiable physical signal.
A group (or phylum) of unicellular EUKARYOTA (or algae) possessing CHLOROPLASTS and FLAGELLA.
A plant subclass of the class Liliopsida (monocotyledons) in the Chronquist classification system. This is equivalent to the Alismatales order in the APG classification system. It is a primitive group of more or less aquatic plants.
Carbonic acid calcium salt (CaCO3). An odorless, tasteless powder or crystal that occurs in nature. It is used therapeutically as a phosphate buffer in hemodialysis patients and as a calcium supplement.
A great expanse of continuous bodies of salt water which together cover more than 70 percent of the earth's surface. Seas may be partially or entirely enclosed by land, and are smaller than the five oceans (Atlantic, Pacific, Indian, Arctic, and Antarctic).
A measure of the total greenhouse gas emissions produced by an individual, organization, event, or product. It is measured in units of equivalent kilograms of CARBON DIOXIDE generated in a given time frame.
The sum of the weight of all the atoms in a molecule.
Production of a radiographic image of a small or very thin object on fine-grained photographic film under conditions which permit subsequent microscopic examination or enlargement of the radiograph at linear magnifications of up to several hundred and with a resolution approaching the resolving power of the photographic emulsion (about 1000 lines per millimeter).
Neodymium. An element of the rare earth family of metals. It has the atomic symbol Nd, atomic number 60, and atomic weight 144.24, and is used in industrial applications.
Erbium. An element of the rare earth family of metals. It has the atomic symbol Er, atomic number 68, and atomic weight 167.26.
A procedure consisting of a sequence of algebraic formulas and/or logical steps to calculate or determine a given task.
Tomography using x-ray transmission and a computer algorithm to reconstruct the image.
Screens which absorb the energy in the x-ray beam that has penetrated the patient and convert this energy into a light pattern which has as nearly as possible the same information as the original x-ray beam. The more light a screen produces for a given input of x-radiation, the less x-ray exposure and thus shorter exposure time are needed to expose the film. In most film-screen systems, the film is sandwiched between two screens in a cassette so that the emulsion on each side is exposed to the light from its contiguous screen.
A trace element that constitutes about 27.6% of the earth's crust in the form of SILICON DIOXIDE. It does not occur free in nature. Silicon has the atomic symbol Si, atomic number 14, and atomic weight [28.084; 28.086].
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 study of the energy of electrons ejected from matter by the photoelectric effect, i.e., as a direct result of absorption of energy from electromagnetic radiation. As the energies of the electrons are characteristic of a specific element, the measurement of the energy of these electrons is a technique used to determine the chemical composition of surfaces.
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)
Lanthanum. The prototypical element in the rare earth family of metals. It has the atomic symbol La, atomic number 57, and atomic weight 138.91. Lanthanide ion is used in experimental biology as a calcium antagonist; lanthanum oxide improves the optical properties of glass.
Characteristics or attributes of the outer boundaries of objects, including molecules.
A property of the surface of an object that makes it stick to another surface.
In horses, cattle, and other quadrupeds, the joint between the femur and the tibia, corresponding to the human knee.
A protective layer of firm, flexible cartilage over the articulating ends of bones. It provides a smooth surface for joint movement, protecting the ends of long bones from wear at points of contact.
An activity in which the body is propelled by moving the legs rapidly. Running is performed at a moderate to rapid pace and should be differentiated from JOGGING, which is performed at a much slower pace.
A synovial hinge connection formed between the bones of the FEMUR; TIBIA; and PATELLA.
A non-vascular form of connective tissue composed of CHONDROCYTES embedded in a matrix that includes CHONDROITIN SULFATE and various types of FIBRILLAR COLLAGEN. There are three major types: HYALINE CARTILAGE; FIBROCARTILAGE; and ELASTIC CARTILAGE.
A polypeptide substance comprising about one third of the total protein in mammalian organisms. It is the main constituent of SKIN; CONNECTIVE TISSUE; and the organic substance of bones (BONE AND BONES) and teeth (TOOTH).

Gamma-Actinin, a new regulatory protein from rabbit skeletal muscle. I. Purification and characterization. (1/338)

A new regulatory protein which we have designated as gamma-actinin has been isolated from native thin filaments of rabbit skeletal muscle. Depolymerized native thin filaments were fractionated by salting out with ammonium sulfate, and the precipitates obtained at 40--60% ammonium sulfate saturation were further subjected to DEAE-Sephadex and Sephadex G-200 column chromatography. The purified gamma-actinin was shown to have a chain weight of 35,000 daltons and had a strong inhibitory action on the polymerization of G-actin. The results of amino acid analysis indicated a unique amino acid composition of gamma-actinin as compared with other structural proteins of muscle. Non-polar and neutral amino acid residues were abundant. One cysteine residue was contained per one molecule of gamma-actinin and played a critical role in the maintenance of the inhibitory activity. Pelleting of gamma-actinin with F-actin showed that gamma-actinin binds to F-action.  (+info)

Single-polymer dynamics in steady shear flow. (2/338)

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)

Electric birefringence of recombinant spectrin segments 14, 14-15, 14-16, and 14-17 from Drosophila alpha-spectrin. (3/338)

Members of the spectrin protein family can be found in many different cells and organisms. In all cases studied, the major functional role of these proteins is believed to be structural rather than enzymatic. All spectrin proteins are highly elongated and consist mainly of homologous repeats that constitute rigid segments connected in tandem. It is commonly believed that the details of the spectrin function depend critically on the flexibility of the links between the segments. Here we report on a work addressing this question by studying the transient electric birefringence of recombinant spectrin fragments consisting of segments 14, 14-15, 14-16, and 14-17, respectively, from Drosophila alpha-spectrin. Transient electric birefringence depends sharply on both molecular length and flexibility. We found that the birefringence relaxation time of segment 14 measured at 4 degrees C, but scaled to what is expected at 20 degrees C, equals 16 ns (+/-15%) at pH 7.5 and ionic strength 6 mM. This is consistent with this single segment being rigid, 5 nm long and having an axial ratio equal to about two. Under the same conditions, segments 14-15, 14-16 and 14-17 show relaxation times of 45, 39 and 164 ns (all +/-20%), respectively, scaled to what is expected at 20 degrees C. When the temperature is increased to 37 degrees C the main relaxation time for each of these multisegment fragments, scaled to what is expected at 20 degrees C, increased to 46, 80, and 229 ns (all +/-20%), respectively. When the ionic strength and the Debye shielding is low, the dynamics of these short fragments even at physiological temperature is nearly the same as for fully extended weakly bending rods with the same lengths and axial ratios. When the ionic strength is increased to 85 mM, the main relaxation time for each of these multisegment fragments is reduced 20-50% which suggests that at physiological salt and temperature conditions the links in 2-4-segment-long fragments exhibit significant thermally induced flexing. Provided that the recombinant spectrin fragments can serve as a model for native spectrin, this implies that, at physiological conditions, the overall conformational dynamics of a native spectrin protein containing 20-40 segments equals that of a flexible polymer.  (+info)

Designing conditions for in vitro formation of amyloid protofilaments and fibrils. (4/338)

We have been able to convert a small alpha/beta protein, acylphosphatase, from its soluble and native form into insoluble amyloid fibrils of the type observed in a range of pathological conditions. This was achieved by allowing slow growth in a solution containing moderate concentrations of trifluoroethanol. When analyzed with electron microscopy, the protein aggregate present in the sample after long incubation times consisted of extended, unbranched filaments of 30-50 A in width that assemble subsequently into higher order structures. This fibrillar material possesses extensive beta-sheet structure as revealed by far-UV CD and IR spectroscopy. Furthermore, the fibrils exhibit Congo red birefringence, increased fluorescence with thioflavine T and cause a red-shift of the Congo red absorption spectrum. All of these characteristics are typical of amyloid fibrils. The results indicate that formation of amyloid occurs when the native fold of a protein is destabilized under conditions in which noncovalent interactions, and in particular hydrogen bonding, within the polypeptide chain remain favorable. We suggest that amyloid formation is not restricted to a small number of protein sequences but is a property common to many, if not all, natural polypeptide chains under appropriate conditions.  (+info)

Electric field-induced transient birefringence and light scattering of synthetic liposomes. (5/338)

The dynamics of electric field-induced transient birefringence Deltan(t) and light scattering (detected as turbidity) of 190 nm diameter unilamellar vesicles of dioleoylphosphatidylcholine are investigated as a function of applied field strength E, length of the square pulse Deltat, lipid concentration, mean hydrodynamic diameter , ionic strength, and temperature. Generally, induced birefringence exclusively is observed at low lipid concentration and below certain threshold values of E and Deltat, whereas concomitant induced turbidity appears at high lipid concentration and above thresholds values of E and Deltat. Turbidity is monitored through the change in transmitted intensity DeltaS parallel(t) and DeltaS perpendicular(t) of light polarized parallel and perpendicular to the applied field E. The field-induced structural changes are reflected in double-exponential forward relaxation and triple-exponential reverse relaxation of the positive birefringence, and in non-exponential relaxations of DeltaS parallel (t) and DeltaS perpendicular(t). Under the field, the associated physical events are interpreted as elongation of the spherical bilayer shells in the direction of E, linear chain formation (pearling) of the induced dipolar liposomes parallel to E, and partial fusion of adjoining vesicles within the chains. Under conditions where electroporation can be detected, pore opening succeeds the elongation of the vesicles. After termination of the field, the vesicles return to their original time average spherical shape, the oriented chains randomize and disintegrate, and the fused structures are converted either to unilamellar or multilamellar vesicles.  (+info)

Biomechanical, histological and immunohistological studies of patellar cartilage in an ovine model of osteoarthritis induced by lateral meniscectomy. (6/338)

OBJECTIVE: To evaluate the biomechanical, histological and immunohistochemical changes induced in patellar articular cartilage (AC) in ovine stifle joints 3 months after bilateral lateral meniscectomy, a procedure known to induce experimental osteoarthritis (OA) in the femoro-tibial joint (FTJ). METHODOLOGY: Fifteen mature adult Merino female sheep were used in this study. Ten were subjected to bilateral-lateral meniscectomy, while the remaining five were used as 'non-operated controls' (NOC). All animals were killed 3 months post-surgery. Topographical biomechanical indentation tests were performed on each patellae using a UMIS-2000 micro-indentation system. Initial load, relaxed and unload shear moduli were determined using an elastic analytical model, while the permeability was assessed by comparing the indentation response to a simulated indentation test conducted using a poroelastic finite element model. Immunohistochemical, normal and polarized histological studies were performed on each specimen after biomechanical testing. RESULTS: Patellar AC from meniscectomized joints exhibited an overall decrease in initial (-34%), relaxed (-32%) and unload shear modulus (-22%), and an increase in the permeability (+72%) relative to NOC cartilage (P< 0.01). The most significant differences in mechanical properties occurred on the lateral and central aspects of the patellae. There were no significant histological difference in staining between sections from NOC and meniscectomized joint AC using Toluidine Blue, a dye which binds to proteoglycans. However immunohistochemical staining with monoclonal antibody MAb 3B3(-), a putative marker of early OA change in PGs, demonstrated increased binding in the lateral and central regions of patellar sections from meniscectomized joints relative to the same regions of NOC AC. Moreover polarized light microscopy of Picro Sirius red stained sections revealed a significant decrease in birefringence intensity in the superficial-middle zones of the lateral and central regions of the patellar cartilage derived from the meniscectomized joints. CONCLUSION: This study has demonstrated that lateral meniscectomy is a procedure which was known to induce classical OA like changes in AC and subchondral bone of the FTJ also produced an early pathological response in the patellar AC.  (+info)

Calculation of protein form birefringence using the finite element method. (7/338)

An approach based on the finite element method (FEM) is employed to calculate the optical properties of macromolecules, specifically form birefringence. Macromolecules are treated as arbitrarily shaped particles suspended in a solvent of refraction index n1. The form birefringence of the solution is calculated as the difference in its refractive index when all the particles of refractive index n2 are either parallel to or normal to the direction of the polarization of light. Since the particles of interest are small compared to the wavelength of light, a quasi-static approximation for the refractive index is used, i.e., that it is equal to the square root of the dielectric constant of the suspension. The average dielectric constant of the mixture is calculated using the finite element method. This approach has been tested for ellipsoidal particles and a good agreement with theoretical results has been obtained. Also, numerical results for the motor domains of ncd and kinesin, small arbitrarily shaped proteins with known x-ray structures, show reasonable agreement with the experimental data obtained from transient electric birefringence experiments.  (+info)

The effects of increasing the reverse curve of Spee in a lower archwire examined using a dynamic photo-elastic gelatine model. (8/338)

This paper describes the development and testing of a dynamic in vitro photo-elastic model for evaluating the effects of orthodontic mechanics on an entire arch of teeth. A model of a mandibular arch was made and the teeth were embedded in a gelatine material with a high level of mechanical creep which permitted tooth movement in response to orthodontic forces. The excellent photo-elastic properties of this material also facilitated the analysis of the stress distribution around the roots of the teeth. The model of a mandibular arch was used to investigate the tooth movements and stress distributions produced by increasing the reverse curve of Spee in a 0.018 x 0.025-inch stainless steel archwire. The results revealed that a 1-mm reverse curve of Spee increased the arch length by 1.6 mm, but increasing the reverse curve of Spee to 5 mm did not increase arch length further. Photo-elastic analysis showed an increased stress distribution around the roots of the incisors and molars as the reverse curve of Spee was increased in the archwire.  (+info)

Abstract: : Purpose: To determine the wavelength dependence of corneal birefringence. Methods: A corneal polarimeter described previously (ARVO 2001; IOVS 2002;43:82-86) was modified to incorporate a multi-spectral light source and a video detector. Corneal birefringence was measured by using a variable retarder to null the fourth Purkinje image viewed through crossed polarizers. The corneas of five eyes of five normal subjects were measured three times at each of several wavelengths from 440 to 700 nm. Results: Corneal axis did not vary significantly with wavelength. Corneal retardance ranged from 85-143 nm in the five subjects. Pooling variances across subjects, the within wavelength s.d. was 10.2 nm and the between wavelength s.d. was 5.3 nm. Conclusion: Corneal birefringence was constant across visible wavelengths. This is consistent with the frequently assumed mechanism of form birefringence, i.e., birefringence due to oriented collagen fibrils in the corneal stroma. ...
Corneal birefringence affects polarization-sensitive optical measurements of the eye. Recent literature supports the idea that corneal birefringence is biaxial, although with some disagreement among reports and without considering corneas with very low values of central retardance. This study measured corneal retardation in eyes with a wide range of central corneal retardance by means of scanning laser polarimetry (GDx-VCC™, Carl Zeiss Meditec, Inc.), which computes the retardance and slow axis of the cornea from images of the bow tie pattern formed by the radial birefringence of the macula. Measurements were obtained at many points on the cornea by translating the instrument. Data were compared to calculations of the retardation produced by a curved biaxial material between two spherical surfaces. Most corneas showed one or two small areas of zero retardance where the refracted ray within the cornea aligned with an optical axis of the material. The retardation patterns in these corneas could ...
Photoreceptors in the central macula are prone to damage in many progressive sight threatening diseases, including AMD. Direct assessment of these photoreceptors is difficult in the aging eye, making indirect techniques particularly valuable. Indirect techniques must utilize unique optical signatures to isolate structures of interest and permit quantitative metrics for comparison. As a complementary technique for assessing the central macula, SLP imaging can utilize the phase retardation signal generated by the photoreceptor axons of the HFL, the only known birefringent structure in the central macula, to selectively study the central macular photoreceptor density and regularity. Similar to the nerve fiber layer (NFL), the magnitude of the phase retardation signal in the central macula would be proportional to the number of axons that make up the Henle fiber layer at any given eccentricity. These central photoreceptor axons splay out in a well-organized, radially symmetric pattern,18 suggesting ...
The |i|Journal of Biomedical Optics|/i| (JBO) publishes peer-reviewed papers on the use of novel optical systems and techniques for improved health care and biomedical research.
The Faraday rotation is discriminated from linear birefringence in fiber current sensor by a time multiplexing of two different states of polarization at the input of the fiber. In this way an accurate current measurement can be carried out whatever the magnitude of the linear birefringence may be. A polarization multiplexing system using two identical laser diodes is presented. The experimental results and a method of compensating the imperfections of the optical components are also discussed ...
Nearly all circular dichroism (CD) and linear dichroism (LD) spectrometers use a photoelastic modulator (PEM) in which an optical element is stressed using a high-tension voltage (HT) signal to induce birefringence. The birefringence consequently produces a phase difference between perpendicular polarization states of light passing through the PEM that is appropriate to CD or LD measurements. However, even without external stress (i.e., at zero HT) the PEM exhibits an inherent static birefringence. This article discusses the characterization of the static birefringence inherent to a PEM and its effect on the measurement of CD and LD, as well as the development and implementation of a novel model that accommodates for the presence of static birefringence. The model is validated with CD and LD experiments using purely chiral or linearly structured molecules (camphorsulfonic acid and chrysazin).. PDF Article ...
In this dissertation, liquid crystal (LC) materials and devices are investigated in order to meet the challenges for photonics and displays applications. We have studied three kinds of liquid crystal materials: positive dielectric anisotropic LCs, negative dielectric anisotropic LCs, and dual- frequency LCs. For the positive dielectric anisotropic LCs, we have developed some high birefringence isothiocyanato tolane LC compounds with birefringence ~0.4, and super high birefringence isothiocyanato biphenyl-bistolane LC compounds with birefringence as high as ~0.7. Moreover, we have studied the photostability of several high birefringence LC compounds, mixtures, and LC alignment layers in order to determine the failure mechanism concerning the lifetime of LC devices. Although cyano and isothiocyanato LC compounds have similar absorption peaks, the isothiocyanato compounds are more stable than their cyano counterparts under the same illumination conditions. This ultraviolet-durable performance of
We report an optical film with electrically tunable birefringence in which the liquid crystals (LCs), mixed with the host polymer, form longrange ordering. The film was prepared through polymerization without phase separation between the LCs and polymers. Driving voltage below 30 V for full switching of birefringence is achieved in a 6 μm-thick film. Electro-optical investigations for the film suggest that the long-range ordering of the LCs mixed in the film caused by polymerization lead to rotations of the LCs as well as optical anisotropy in the film. These films with electrically tunable birefringence could have applications as flexible light modulators and phase retardation films for 2D-3D image switching. © 2014 Optical Society of America. ...
The |i|Journal of Biomedical Optics|/i| (JBO) publishes peer-reviewed papers on the use of modern optical technology for improved health care and research.
Poly-3-hexylthiophene (P3HT) nanofibers are 1D crystalline semiconducting nanostructures, which are known for their application in photovoltaics. Due to the internal arrangement, P3HT nanofibers possess optical anisotropy, which can be enhanced on a macroscale if nanofibers are aligned. Alternating electric field, applied to a solution with dispersed nanofibers, causes their alignment and serves as a method to produce solid layers with ordered nanofibers. The transmission ellipsometry measurements demonstrate the dichroic absorption and birefringence of ordered nanofibers in a wide spectral range of 400-1700 nm. Moreover, the length of nanofibers has a crucial impact on their degree of alignment. Using electric birefringence technique, it is shown that external electric field applied to the solution with P3HT nanofibers can cause direct birefringence modulation. Dynamic alignment of dispersed nanofibers changes the refractive index of the solution and, therefore, the polarization of transmitted ...
Sex chromosomes in crane-fly spermatocytes move polewards at anaphase after the autosomes have reached the poles. In Nephrotoma abbreviate the sex chromosomes are 8 μm long by 3.5 μm wide and have two orientations when they move: the long axis of the sex chromosome is either perpendicular or parallel to the spindle axis. We assume (1) that when a sex chromosome is perpendicular to the spindle axis it has a chromosomal spindle fibre to each pole, one from each kinetochore, as in other species; and (2) that when a sex chromosome is parallel to the spindle axis each kinetochore has spindle fibres to both poles, i.e. that the latter sex chromosomes are maloriented.. We irradiated one kinetochore of one sex chromosome using an ultraviolet microbeam. When both sex chromosomes were normally oriented, irradiation of a single kinetochore permanently blocked movement of both sex chromosomes. Irradiation of non-kinetochore chromosomal regions or of spindle fibres did not block movement, or blocked ...
Over the past twenty years our understanding of polymer solutions has undergone a dramatic evolution. New methods and concepts have extended the frontier of the theory from dilute solutions in which polymers move independently of each other, to concentrated solutions where many polymersentangle with each other. This book provides a comprehensive account of the modern theory for the dynamical properties of polymer solutions. This includes viscoelasticity, diffusion, dynamic light scattering and flow and electric birefringence. Nonlinear viscoelasticity is discussed in detail on thebasis of molecular dynamical models. The book fills a gap between classical theory and modern developments and constructs a consistent picture for the dynamics of polymer solutions over the entire concentration range.
Cascadability and simplicity of design and operation are primary attributes of a novel electrooptic polarization transformer for reset-free endless polarization control that allows general polarization transformations from any arbitrarily varying input and into any arbitrarily varying output polarization by producing adjustment elliptical birefringence of constant total phase retardation in a single-mode waveguide. Here, a particular transformation is obtained by adjusting the azimuth of linear birefringence and the ratio of linear to circular birefringence. In this integrated-optic realization, the endless polarization transformer includes at least one cascadable transformer section comprising a first TE←→TM mode converter followed by a first TE/TM phase shifter followed by a second TE←→TM mode converter and a second TE/TM phase shifter. The sections are formed over a birefringent waveguide capable of supporting propagation of TE and TM optical signal modes.
TY - JOUR. T1 - Inverse Thermoreversible Mechanical Stiffening and Birefringence in a Methylcellulose/Cellulose Nanocrystal Hydrogel. AU - Hynninen, Ville. AU - Hietala, Sami. AU - McKee, Jason R.. AU - Murtomäki, Lasse. AU - Rojas Gaona, Orlando. AU - Ikkala, Olli. AU - Nonappa, Nonappa. PY - 2018/5/7. Y1 - 2018/5/7. N2 - We show that composite hydrogels comprising methyl cellulose (MC) and cellulose nanocrystal (CNC) colloidal rods display a reversible and enhanced rheological storage modulus and optical birefringence upon heating, i.e., inverse thermoreversibility. Dynamic rheology, quantitative polarized optical microscopy, isothermal titration calorimetry (ITC), circular dichroism (CD), and scanning and transmission electron microscopy (SEM and TEM) were used for characterization. The concentration of CNCs in aqueous media was varied up to 3.5 wt % (i.e, keeping the concentration below the critical aq concentration) while maintaining the MC aq concentration at 1.0 wt %. At 20 °C, MC/CNC ...
Polydisperse fiber networks are the basis of many natural and manufactured structures, ranging from high-performance biobased materials to components of living cells and tissues. The formation and behavior of such networks are given by fiber properties such as length and stiffness as well as the number density and fiber-fiber interactions. Studies of fiber network behavior, such as connectivity or rigidity thresholds, typically assume monodisperse fiber lengths and isotropic fiber orientation distributions, specifically for nano scale fibers, where the methods providing time-resolved measurements are limited. Using birefringence measurements in a microfluidic flow-focusing channel combined with a flow stop procedure, we here propose a methodology allowing investigations of length-dependent rotational dynamics of nanoscale polydisperse fiber suspensions, including the effects of initial nonisotropic orientation distributions. Transition from rotational mobility to rigidity at entanglement ...
Birefringent materials have a wide range of optical applications. Single crystals of calcium carbonate and barium borate have been well known as inorganic birefringent materials. Organic single crystals such as urea have also been known to show birefringence. Since birefringence is related to crystal structures, studies on molecular structures and packing in a crystal are important. In 1957, birefringence of tetrakis(4-phenylphenyl)silane was reported (Hinch & Krc, 1957). Recently, birefringence of single crystals of phenyl-substituted linear oligosilanes and their application to polarizers have been reported (Matsumoto & Tanaka, 2008). From these results, crystals of phenyl-substituted silicon compounds seem interesting as potential optical materials. We report herein the synthesis and X-ray crystal analysis of a phenyl-substituted cyclotetrasilane.. The coupling of 1,3-dibromo-1,1,3,3-tetra-tert-butyl-2,2-diphenyltrisilane and dichlorodiisopropylsilane with lithium in tetrahydrofuran (THF) ...
The results of optical modeling of biological tissues polycrystalline multilayer networks have been presented. Algorithms of reconstruction of parameter distributions were determined that describe the linear and circular birefringence. For the separation of the manifestations of these mechanisms we propose a method of space-frequency filtering. Criteria for differentiation of benign and malignant tissues of the women reproductive sphere were found ...
The processing of optical polymers in the production of liquid crystal displays (LCDs) and lenses tends to produce birefringence in the materials. Man
Roshe4282-Shoes Roshe Trainers Women Yellow Gray,birefringence threshold on the molecular weight ,In finance, portfolio performance assessment is an important area of research. The two popular indices of performance are the Jensens alpha and the Sharpe index. However there are a number of shortcomings of the above measures that have been highlighted in the literature. We propose a new measure of performance
An electrically dimmable rear-view mirror for motor vehicles of simple and robust construction, suitable for use as an outside mirror or as an interior mirror possessing a transmission layer which is composed of a PLZT ceramic, on which a linear birefringence can be imposed by means of a controlling electric field. The transmission layer is located between a linear polarizer and a reflective layer, the latter being designed as a dielectric multilayer arrangement. Suitable comb-type electrodes are located on that side of the reflective layer which faces away from the transmission layer and, if appropriate, on that side of the polarizer which faces the transmission layer, the function of these comb-type electrodes being to generate the controlling field. The polarizer defines the direction of polarization, which is inclined at 45 with respect to the field direction and/or the optical axis of the transmission layer. The strength of the electric field controlling the dimming effect is regulated in a manner
O. Mykhaylyk. Soft Matter Analytical Laboratory, Department of Chemistry, The University of Sheffield, Sheffield, S3 7HF, UK. Since polymeric liquids subjected to an external field (flow) often respond with a related anisotropy of their refractive index and stress, flow birefringence is commonly used for structural characterization of these materials. In this respect, rotational geometries are well suited for visual observations of the flow and, consequently, mechano-optical rheology of polymeric liquids. New applications of a rheo-optical method based on a combination of rotational rheology and a recently developed optical technique - shear-induced polarized light imaging (SIPLI) are presented [1]. Simultaneous rheo-optical studies using rheo-SIPLI have already been successfully used for characterization of self-assembled copolymers and liquid crystals [1, 2]. The proposed rheo-optical method is also effective for studying flow-induced crystallization of semi-crystalline polymers (FIC) [3]. ...
Equipment in the colloidal and particle technology laboratories includes an atomic force microscope, a dynamic light scattering apparatus, a flow birefringence system, an imaging ellipsometer, a Brewster angle microscope, Langmuir troughs for BAM analysis and spectroscopic analysis of monolayers at liquid/vapor and liquid/liquid interfaces, Sensadyne bubble tensiometer, Cahn dynamic contact angle system, an image analysis system for sessile and pendant drop analysis, HPLC with evaporative mass and UV detectors, particle size analyzers, various testers for powder flow and mechanics, and turbulent flow heat transfer and drag reduction circulation loops.. ...
waveplate, Phase retardation plate, Phase plates, compensator, retarder, Zo Order, Lo Order, Zero Order, Low Order, Crystal, Quartz, shifter, polarization rotators, birefringence, electro-optic High, Energy, Waveplates
Abstract: Gravitational waves (GWs) provide an excellent opportunity to test the gravity in the strong gravitational fields. In this article, we calculate the waveform of GWs, produced by the coalescence of compact binaries, in an extension of the Chern-Simons gravity by including higher derivatives of the coupling scalar field. By comparing the two circular polarization modes, we find the effects of amplitude birefringence and velocity birefringence of GWs in their propagation caused by the parity violation in gravity, which are explicitly presented in the GW waveforms by the amplitude and phase modifications respectively. Combining the two modes, we obtain the GW waveforms in the Fourier domain, and find that the deviations from those in General Relativity are dominated by effects of velocity birefringence of GWs. In addition, we also map the effects of the parity violation on the waveform onto the parameterized post-Einsteinian (PPE) framework and identify explicitly the PPE parameters ...
We have several instruments for determining the polarization properties of materials. All of them are based on Mueller matrix measurements. Among the measurements we can provide: Birefringence mappingBirefringence imagingReal-time (video rate) birefringence imagingMueller matrix microscopyMueller ma...
Faint levels of circular polarization (Stokes V) have been detected in several relativistic jets. While typically less than a few percent, circular polarization can give us critical insight into the underlying nature of the jet plasma. Circular polarization can be produced through a process known as linear birefringence, in which initially linearly polarized emission produced in one region of the jet is altered by Faraday rotation as it propagates through other regions of the jet with distinct magnetic field orientations. Recently, Marscher has developed the Turbulent Extreme Multi-Zone (TEMZ) model for blazar emission, in which turbulent plasma crossing a standing shock in the jet is represented by a collection of thousands of individual plasma cells, each with distinct magnetic field orientation. In order to test whether the TEMZ model can reproduce circularly polarized radiation at levels comparable to those observed in blazars, I have developed a numerical algorithm to solve the full Stokes
Ammonium dihydrogen phosphate (ADP), also and better known as monoammonium phosphate (MAP) in order not to confuse it with adenosine diphosphate (ADP), with formula NH4H2PO4, is formed when a solution of phosphoric acid is added to ammonia until the solution is distinctly acidic. It crystallizes in tetragonal prisms. Monoammonium phosphate is often used in the blending of dry agricultural fertilizers. It supplies soil with the elements nitrogen and phosphorus in a form usable by plants. The compound is also a component of the ABC powder in some dry chemical fire extinguishers. This substance is also supplied in an emerald green, amethyst, aquamarine and any other color available, crystal growing box kit for children. Solid monoammonium phosphate shows a dissociation pressure of ammonia of 0.05 mm Hg at 125 °C based on the decomposition reaction as follows: NH4H2PO4(s) ⇌ NH3(g) + H3PO4(l) ADP is a widely used crystal in the field of optics due to its birefringence properties. As a result of ...
Among the signs of activity in excitable membranes, the action current (electrical spike) has been extensively studied. Recently, a new approach with optical methods has been rewarding. In nerves, a transient, rapid change of light scattering, birefringence and induced fluorescence can be observed during the passage of the action current. These optical effects are synchronous with the electrical spike and are therefore called the optical spikes. Birefringence decreases during excitation in the giant axon of the squid, the walking nerves of Maia, the vagus nerve of the rabbit, but it increases in the olfactory nerve of the pike, which contains 4 million nonmedullated nerve fibres. Light scattering increases or decreases depending on the angle of observation. Vitally stained nerves with fluorescent probes show an increase and a shift in the wavelength distribution of the fluorescent spike. ...
In previous papers on the micellar organization of the nerve fibre, attention has been directed almost entirely to the lipoid-containing sheaths. Polarized light and X-ray diffraction studies have emphasized the similarity of the architecture of these structures over a wide range of animal forms, from the highly myelinated nerves of vertebrates to the so-called non-medullated fibres of invertebrates (Schmitt, Bear and Clark 1935; see preceding paper for other references). To date little more than a beginning has been made with analysis of the ultrastructure of the axoplasm. This has been due largely to technical difficulties arising from the small size and weak birefringence of the axons so far studied, from the unfavourable position of the axis cylinder within more or less complex sheaths, and from the extreme sensitivity of this colloid to the action of reagents. Valentin (1861), Klebs (1865), v. Ebner (1882), and Friedlaender (1889), found no birefringence in the fresh axis cylinder, although ...
0229] Using the two active and one passive dithering systems of the optical display system 640 is it possible to obtain eight copies of the original image, if desired, namely that provided at pixel 660, for example. Such eight copies may be obtained for every field for every frame, if desired and, thus, provide a macro pixel effectively about eight times the size of the pixel 660. In another embodiment, the data picked off the incoming analog signal or other video signal that operates the pixel 660, e.g., to turn it on or off, may be selected at the appropriate time to drive the pixel 660; and subsequently the pixel 661 may be operated as a function of information picked off the incoming video or analog signal representing the desired operation of the pixel 661 for interlaced fields operation of a conventional NTS or PAL system. However, additionally, if desired, the information from the incoming signal also could be picked off to represent the on/off or intensity effect of a pixel presented at ...
In between stress and strain, which one is the more fundamental physical quantity? Or is it the case that each is defined independent of the other and so nothing can be said about their order? Is this the case? To begin with these questions, consider the fact that first we have to apply a force to an object and it is only then that the object is observed to have been deformed or strained. Accordingly, one may say that forces produce strains, and therefore, it seems that stress has to be more fundamental. If so, how come stress cannot be measured directly? This is the paradox I would like to address here. Of course, to begin with, my position is that you can never directly measure stress. I have read somewhere an argument (and forgot exactly where!) that even in photoelasticity what you really measure is strain. The argument, essentially, is this: Birefringence arises because the molecular chains in the photoelastic polymer get stretched. (In case of crystals, stress-induced birefringence ...
In between stress and strain, which one is the more fundamental physical quantity? Or is it the case that each is defined independent of the other and so nothing can be said about their order? Is this the case? To begin with these questions, consider the fact that first we have to apply a force to an object and it is only then that the object is observed to have been deformed or strained. Accordingly, one may say that forces produce strains, and therefore, it seems that stress has to be more fundamental. If so, how come stress cannot be measured directly? This is the paradox I would like to address here. Of course, to begin with, my position is that you can never directly measure stress. I have read somewhere an argument (and forgot exactly where!) that even in photoelasticity what you really measure is strain. The argument, essentially, is this: Birefringence arises because the molecular chains in the photoelastic polymer get stretched. (In case of crystals, stress-induced birefringence ...
We theoretically propose a method to enhance dramatically a magnetochiral (MC) effect by using the photonic crystals composed of a multiferroic material. The MC effect, the directional birefringence even for unpolarized light, is so small that it has been difficult to observe experimentally. Two kinds of periodic structures are investigated: (a) a multilayer and (b) a stripe composed of a magnetochiral material and air. In both cases, the difference in reflectivity between different magnetization directions is enhanced by a factor of hundreds compared with a bulk material ...
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A reflective polarizer and a dichroic polarizer are combined to provide an improved optical polarizer. The dichroic and reflective polarizers are typically in close proximity to each other, and are preferably bonded together to eliminate the air gap between the polarizers. The combination of the two polarizers provides a high reflectivity of one polarization and high transmission for the perpendicular polarization from the reflective polarizer side of the combined polarizer, and high absorption and transmission for light of orthogonal polarization from the dichroic polarizer side. The combination also reduces iridescence as seen in transmission and when viewed in reflection from the dichroic polarizer side. The increased extinction ratio and low reflectivity of the optical polarizer allows use of a lower extinction ratio dichroic polarizer in applications requiring a given extinction ratio and high transmission.
MARIN SANTIBANEZ, B.M. et al. Qualitative analysis of the capillary flow stability of spurting materials by using transmitted light intensity measurements. Rev. mex. fis. [online]. 2004, vol.50, n.6, pp.562-568. ISSN 0035-001X.. The stability in the capillary flow of spurting materials was analyzed by following the temporal variation of their average birefringence. Two different fluids were analyzed, a high-density polyethylene melt, and an aqueous micellar solution of Cetylpyridinium Chloride and Sodium Salicylate. Birefringence changes were detected through measurements of the transmitted light intensity and video images of the flow channel. Transmitted light intensity measurements were more sensitive and provided better information about the flow stability than pressure ones. An unstable flow region was present in the micellar solution before the onset of spurt. Also, there were periodic changes in the optical properties of both fluids, in the spurt region and at higher shear rates, which ...
The two independent refractive indices of anisotropic crystals are quantified in terms of their birefringence, a measure of the difference in refractive index.
The authors demonstrate a high performance electrically controlled birefringence (ECB) mode with solution-derived La{sub 2}O{sub 3} films at various molar concentrations. Uniform and homogeneous liquid crystal (LC) alignment was spontaneously achieved on the La{sub 2}O{sub 3} films for lanthanum concentrations at ratios greater than and equal to 0.2. A preferred orientation of LC molecules appeared along the filling direction, and the LC alignment was maintained via van der Waals force by nanocrystals of the La{sub 2}O{sub 3} films. The LC alignment mechanism was confirmed by x-ray photoelectron spectroscopy and high-resolution transmission electron microscopy analysis. Superior electro-optical characteristics of the ECB cells constructed with solution-derived La{sub 2}O{sub 3} films were observed, which suggests that the proposed solution-derived La{sub 2}O{sub 3} films have strong potential for use in the production of advanced LC displays. ...
The export of the calcitic platelets (coccoliths) of coccolithophores to the sea floor acts as a long-term sink of carbon. In order to understand the effects of current ocean acidification on coccolithophore calcification, it is important to estimate the amount of calcite that is bound in single coccoliths, which - due to their minuteness (1-10 μm) - cannot be individually weighed. To estimate single coccolith weights, this study takes advantage of the birefringence method (Beaufort, 2005), which links the interference color of calcite under polarized light with calcite thickness. Two similar techniques, one using crossed-polarized light (XPL) and one using circular polarized light (CPL), were tested to compare coccolith weight estimates of cultured single clones of Gephyrocapsa oceanica, which - in a previous study (Rickaby et al., 2010) - were grown in increasing concentrations of dissolved inorganic carbon (DIC) but constant pH-levels (~8.1) to reflect long-term buffering of the ocean. In ...
Looking for online definition of Spindle fibers in the Medical Dictionary? Spindle fibers explanation free. What is Spindle fibers? Meaning of Spindle fibers medical term. What does Spindle fibers mean?
Our results identify a dmd morpholino cocktail that induces a high penetrance of muscle lesions and strongly resembles the zebrafish dmd mutant phenotype. We also show that the HDAC inhibitor TSA rescues both dmd-MO and dmd mutant muscle lesions. By comparing different approaches to scoring muscle lesions, our study confirms a previous report 13 that simple assessment of the muscle birefringence pattern in whole larvae, using a stereomicroscope, is a reliable approach to scoring the dmd-MO or dmd mutant phenotype following chemical treatment. Thus, our work identifies optimal morpholino and phenotypic scoring approaches for dystrophic zebrafish, further enhancing the zebrafish dmd model for rapid and cost-effective small molecule screening.. Our work provides additional support for using cocktails of non-overlapping morpholinos targeted against a single gene in order to provide more robust knock down and reduce non-specific morpholino toxicity than by using individual morpholinos 26,29,30,31. We ...
!%Carl Zeiss MicroImaging Inc.s%! Axio Scope.A1 offers polarization microscopy. With minimal effort, six versions of the microscope can be specifical
TY - JOUR. T1 - Measurement of circular dichroism of ferroelectric fresnoite Ba 2Si2TiO8. AU - Asahi, Toni. AU - Osaka, Tetsuya. AU - Abrahamsb, Sidney C.. AU - Matsuki, Ryo. AU - Asai, Hiroshi. AU - Nanamatsu, Satoshi. AU - Kobayashi, Jinzo. PY - 2003/12/1. Y1 - 2003/12/1. N2 - The urgent goal of the optical polarimetry of solids is simultaneous and accurate measurements of circular dichroism together with circular birefringence. Needless to say, measurements of circular phenomena are extremely difficult compared with those of linear ones. As for circular birefringence, 170 years elapsed since its discovery by Arago until the development of the HAUP method, by which the accurate measurements of the gyration tensor components of a solid became possible for the first time. Subsequent to appearance of the HAUP method, attempts to extend the HAUP theory to being applicable for measurements of circular dichroism of crystals were followed by several authors. However any applications to real crystal ...
This study evaluated the effect of short bouts of stretching on the soleus muscle after immobilization, by measuring the birefringence of the intramuscular connective tissue (ICT) and the muscle fiber area. Thirty rats were divided into five groups: the left soleus was immobilized in the shortened position; after immobilization the animals remained free; after immobilization, the soleus was stretched daily (10 stretches of 60 sec followed by 30 sec rest); after immobilization, the soleus was stretched 3 times a week; control. Immobilization caused a loss of birefringence of the ICT and of muscle fiber area and only daily stretching increased both compared with the control (p , 0.01). In conclusion, short daily bouts of stretching after immobilization induced molecular reorganization of the collagen bundles and muscle fiber hypertrophy in the rat soleus ...
Optically birefringent microstructures are formed within fluoride films that are produced on uranium dioxide by hydrofluorination. The positive molar volume change of the reaction produces nonuniform tensile and compressive stresses around sites of surface roughness which result in optical double refraction.
Mueller matrix polarimetry is the examination of how a sample transforms the polarization state of light. This requires probing the sample with input light of a variety of generated polarization states and analyzing the resulting output states, using a total of at least sixteen irradiance measurements. This allows one to calculate the Mueller matrix, which provides insight into the microstructure of the sample. In imaging applications this can yield additional contrast between different types of materials. Examination of the human retina has the potential to reveal not only ocular conditions, but also neurological disorders due to the fact that the retina is made up of neural tissue. Deposits of amyloid-beta in the brain are a standard biomarker for Alzheimers disease. Similar deposits have been identified in the retina. By studying ex vivo human retinae, members of Campbell Labs have shown that these deposits can be imaged label-free using Mueller matrix polarimetry, and that their number ...
A projection system includes a light source producing illumination light, an imager disposed to receive the illumination light, and a projection lens disposed to receive the illumination light from the imager. The imager includes an intrinsic polarizer. The intrinsic polarizer can be an intrinsic polarizer stack including a U.V. curable adhesive.
Toy or novelty including a first polarizer and a second polarizer movable relative to the first polarizer. In a first mode, the first and second polarizers interact to be reflective, and in a second mode, the first and second polarizers is transmissive. The toy may further include an object or image located adjacent the second polarizer, wherein the object or image is viewable through the first and second polarizers in the second mode.
Look at Figure 1, for example; this is a 30 µm thick rock thin-section as viewed between crossed polarizers using a 4X objective for a visual magnification of 40X. The individual mineral grains that make up this rock section are all lying at different orientations, and showing many shades of white and gray. When I view this figure filling up my monitor screen, I can go from grain to grain and name off colors: snow white, off- white, bone, ivory, cream, steel gray, bluish gray, greenish gray, light gray, medium gray, dark gray, charcoal, blue-green gray, olive gray, slate gray, gun metal, mushroom, etc. What I need, however, are not these often-creative verbal descriptions, but a value in nanometers, that the color I am looking at corresponds to; this is why I prefer a Michel-Lévy Interference Color Chart with colors printed as accurately as possible, but with the names of the colors as well. Only with an accurate determination of interference color can I obtain the characteristic birefringence ...
PANDA Polarization Maintaining (PM) fibers are designed with high performance properties including excellent birefringence and low attenuation. Corning offers the broadest portfolio of PANDA PM fibers from wavelengths of 400-1550nm and designs such as High NA and Flame Retardant coatings.
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The colours in the image are the result of birefringence and relate to the residual strain in the polystyrene. The pattern of strain is indicative of the flow of material during the injection process and it highlights the injection point (known as a sprue) which can also be identified by a small lump on the surface; the molecular alignment is greatest near this point. Towards the edges of the ruler and along its length, the material becomes more relaxed and as the molecular alignment falls, the retardation of light is less. If heated above the glass transition temperature of polystyrene (about 100 °C), the material will tend to relax, particularly near the sprue. This will result in a wrinkling of the component ...
Video articles in JoVE about muscular dystrophies include Isometric and Eccentric Force Generation Assessment of Skeletal Muscles Isolated from Murine Models of Muscular Dystrophies, Quantitative Magnetic Resonance Imaging of Skeletal Muscle Disease, Analysis of Zebrafish Larvae Skeletal Muscle Integrity with Evans Blue Dye, Transplantation of Induced Pluripotent Stem Cell-derived Mesoangioblast-like Myogenic Progenitors in Mouse Models of Muscle Regeneration, In Situ Immunofluorescent Staining of Autophagy in Muscle Stem Cells, In Vivo Modeling of the Morbid Human Genome using Danio rerio, Analysis of Skeletal Muscle Defects in Larval Zebrafish by Birefringence and Touch-evoke Escape Response Assays, Isolation and Immortalization of Patient-derived Cell Lines from Muscle Biopsy for Disease Modeling, Dos and Donts in the Preparation of Muscle Cryosections for Histological Analysis, Analysis of Embryonic and Larval Zebrafish Skeletal Myofibers from Dissociated Preparations,
Electronic, Birefringence, Electron, Report, Charge, X-ray, Absorption, Potassium, Refractive Indices, Magnetic, Vanadium, Anisotropy, Theoretical Study, Art, Laser, Theoretical Studies, Yag Laser, Rotation, Cations, Temperature
If you have a question about this talk, please contact Duncan Johnstone.. The lecture will highlight three experimental strategies that we have developed for exploring crystallization pathways and structural properties of solids: (i) in-situ solid-state NMR techniques for understanding the time-evolution of crystallization processes, (ii) the study of X-ray birefringence for spatially resolved mapping of the distribution of molecular orientations in materials, and (iii) structure determination of organic materials when single crystals cannot be prepared.. Our in-situ solid-state NMR technique [1-3] for studying crystallization pathways exploits the ability of NMR to selectively detect the solid phase in heterogeneous solid/liquid systems of the type that exist during crystallization from solution. We have shown that this technique can establish the sequence of solid phases formed during crystallization processes [1] and can be exploited in the discovery of new polymorphs [2]. Our most recent ...
B Kahr, ed. Optically Anomalous Crystals. English language edition of Nauka publication by A. Shtukenberg and Y. O. Punin Springer Series in Solid State Science, Springer, Dordrecht, 2007. T Bullard, J Freudenthal, S Avagyan, B Kahr. Test of Cairns-Smiths crystals-as-genes hypothesis Faraday Discussions, 2007, 136, 231-245 See also: Chemical Sciences, 2007, 4, C60. D Cohen, JB Benedict, B Morland, D Chiu, B Kahr. Dyeing polymorphs: The MALDI host 2,5-dihydroxybenzoic acid Cryst. Growth Des. 2007, 7, 492-495. C Isborn, K Claborn, B Kahr. The optical rotatory power of water J. Phys. Chem. A, 2007, 111, 7800-7804. KL Wustholz, ED Bott, CM Isborn, X Li, B Kahr, PJ. Reid. Dispersive kinetics from single molecules oriented in single crystals of potassium acid phthalate J. Phys. Chem. C, 2007, 111, 9146-9156. W Kaminsky, E Gunn, R Sours, B Kahr. Simultaneous false-color imaging of birefringence, extinction, and transmittance at camera speed J. Microscopy, 2007, 228, 153-164. B Kahr, K Claborn The ...
Five monomers 5-[4-(5-cyano-4,5-dihydroisoxazol-3-yl)phenoxy]undecyl acrylate (7a); n-alkyl 3-{4-[5-(acryloyloxyundecyl) oxyphenyl]}-4,5-dihydroisoxazole-5-carboxylate (7b,c for n-butyl and n-hexyl, respectively); 3-{4-[5-(acryloyloxyundecyl) oxyphenyl]}-4,5-dihydroisoxazole-5-carboxylic acid (7d) and (1R,2S,5R)-2-isopropyl-5-methylcyclohexyl acrylate (9) and the corresponding copolymers 10a-d, 11 and homopolymers 12 from 7a and 13 from 9 were designed and synthesized. Except for acrylate 9 which is derived from (-)-menthol, all of the monomers belong to the series containing the isoxazoline ring linked to the acrylate unit by a flexible spacer chain of eleven methylene units. They presented low glass temperature and despite birefringence behavior, these copolymers showed no mesomorphic properties ...
Roids, estrogens, digoxin, iron, and opioids. Treatment acute onset of the lymphatics is often exacerbated by stress and from tropical waters around the sinus of valsalva aneurysms. Bolla m, collette l, blank l, et al: The results of the dermis is homogenized. The first postoperative day. Hrqol data are lacking. There was no dif- strated that resistance used the wells the optimal times be helpful in may outlast the fever is prolonged. Vwf also has been associated with urinary endoscopy usually within responses have been reported.11,185 long-term use of abdominal atheroscle- quency of attacks in hyperkalemic periodic alpha subunit of calcium pyrophos- phate crystals (positive birefringence) in the previous 4 months for bcg ver- bcg. Iiv inactivated influenza vaccine preparations are approved for the postoperative recovery period. The presentation is renal tumors. The middle 24 cm of the muscularis propria. Breast relative with bilateral breast cancer. Oral estrogen replacement lower risk than ...
As I mentioned yesterday, I originally ordered 2 and loved them so much I had to go back and get the other two. The original order was for Birefringence and My Little Glacier. After wearing each of those colors for like, an hour, I realized I had made a grave mistake not ordering the rest of the set. Im hemmed and hawed over it because I knew Id have to have them shipped to me before we left Texas. Finally on the Tuesday before we left, I broke down and placed my order in the morning. I sent an inquiry email to make sure I had selected the proper shipping type to make sure the polishes would get to me on time. Within an hour, I had a very lovely email back from Barbra saying that Id managed to catch her just before she went to the post office, and that she would make sure my order went out that day! I was over the moon on that one. So often when you order things online, youre never sure how long its going to take before they process and ship your order (born pretty store, Im looking at ...
Histones are basic nuclear proteins that are responsible for the nucleosome structure of the chromosomal fiber in eukaryotes. Two molecules of each of…
Dimethyl-Histone H3-K14 Antibody is a Rabbit Polyclonal antibody against Dimethyl-Histone H3-K14. Histones are basic nuclear proteins that are responsible for the nucleosome structure of the chromosomal fiber in eukaryotes. Nucleosomes consist of approxim
H4/e Lysate, 0.1 mg. Histones are basic nuclear proteins that are responsible for the nucleosome structure of the chromosomal fiber in eukaryotes.
Polarcor is a keystone optical element in polarization-dependent isolators, optical modulators, polarimetry systems, ellipsometers, shutters and many other polarization-based devices.
An intrinsic polarizer, including a sheet of PVA-type matrix that includes vinylene polymer blocks, the sheet defining a pass polarization axis and a block polarization axis perpendicular to the pass polarization axis, light having an electrical vector parallel to the pass polarization axis being substantially transmitted through the sheet and light having an electrical vector parallel to the block polarization axis being substantially absorbed by the vinylene blocks, the sheet exhibiting a dichroic ratio of more than 100.
A projection display apparatus (10) uses a modulation optical system (200) that includes a liquid crystal device (210) in combination with a wire grid polarization beamsplitter (240), a wire grid polarization analyzer (270) and a projection lens (285) to form an image. In order to achieve high contrast and maintain high brightness levels, a compensator (260) is provided for minimizing leakage light for pixels in the black (OFF) state. A number of configurations are possible, such as with the compensator (260) disposed in the optical path between the liquid crystal device (210) and the wire grid polarization beamsplitter (240) and with a secondary compensator (265) disposed between wire grid polarization analyzer (270) and the wire grid polarization beamsplitter (240).
Our polarizer mounts take advantage of superior opto-mechanical design with precision machined surfaces, securely held optics, and fine adjustment screws.
In my last post, I discussed what a heart scan score, or coronary calcium score, means. You may recall that coronary calcium serves as an indirect gauge, a
S3-WXG-4 - Manual Polarimeter by S3 Instruments. Application: Polarimeter is an instrument which measures the optical rotation of substances. It can be used in ...
GeniCity.com: Innovations Start Here; Shop for Innovative Research Tools - Hardware, Software, and Reagents in Science & Technology - Directly from the Original Manufacturer.
BioTek Product Accessory, Part Number: 8040562, for use with Cytation 5 自動化影像系統暨多功能光學檢測儀, Cytation 多功能微量盤檢測儀, Cytation 1自動化影像系統暨多功能光學檢測儀 and Synergy H1 多功能微量盤檢測儀
X-ray Polarimetry: A new window in astrophysics, Ed by Ronaldo Bellazzini et al, Published by Cambridge University Press, Cambridge, p 83-87,(proceedings of The Coming of Age of X-ray Polarimetry, Rome, Italy, April 27-30, 2009) ...
A change in birefringence alters the polarization and thereby the fraction of light that is transmitted through the second ... In gemology a different type of refractometer is used to measure index of refraction and birefringence of gemstones. The gem is ... R. Paschotta, article on birefringence Archived 2015-07-03 at the Wayback Machine in the Encyclopedia of Laser Physics and ... In the simplest form, uniaxial birefringence, there is only one special direction in the material. This axis is known as the ...
The birefringence is around 0.06 in the visible light region of the spectrum, but increases sharply in the UV t 0.093 at 200 nm ... The birefringence is 0.070 at 1084 nm increasing to 0.075 at 400 nm. The ultraviolet cutoff limit is below 180 nm. BaB5O8F·xH2O ... birefringence. The transparency deep into the ultraviolet corresponds to a large band gap, whereby it takes a lot of energy to ... Birefringence is 0.0685 at 1064 nm (NIR) to 0.0737 at 400 nm. The band gap is 5.23. Li2Na0.9K0.1B5O8F2 contains a two ...
These crystals exhibit birefringence. Birefringence. ...
S2CID 6452268.CS1 maint: multiple names: authors list (link) Inoué, S.; A. Bajer (1961). "Birefringence in endosperm mitosis". ...
Its birefringence is .0340. Kochite is found in the alkaline igneous complex of East Greenland and is named after Danish ...
Weisstein, Eric W. "Birefringence". scienceworld.wolfram.com, Wolfram Research, 1996-2007. Retrieved 15 August 2013. "What Is A ... as the stress will induce birefringence in the quartz and affect measurements. Fingerprints and droplets of water disrupt light ...
... illustrates weak birefringence; birefringence is directly dependent on the material being anistropic, so since ... sewardite is weakly anistropic, it exhibits weak birefringence. Sewardite has only been found at three locations, in the Tsumeb ...
It is anisotropic and has high birefringence. Its crystal system is monoclinic. The green, chromium-rich variety is called ...
Birefringence. none. Pleochroism. none. Dispersion. .028. Ultraviolet fluorescence. near colorless to light green - inert to ...
Birefringence. δ = 0.009 - 0.010. Pleochroism. Visible. Melting point. Decompose before. Fusibility. Decompose before. ...
Birefringence. δ = 0.033 - 0.037. Pleochroism. Strong: X= colorless, Y= blue, Z= darker blue. ...
Birefringence. δ = 0.076. Pleochroism. Weak; X = bluish green to pale green; Y = yellowish green; Z = deep bluish green to blue ...
Birefringence. None. Pleochroism. None. Dispersion. 0.044. Melting point. Pressure dependent. References. [1][2]. ...
Birefringence. δ = 0.020. Other characteristics. piezoelectric and pyroelectric. References. [1][2]. Major varieties. ...
Birefringence. None. Pleochroism. None. Carbonado, commonly known as black diamond, is one of the toughest forms of natural ...
Birefringence. δ = 0.003. Pleochroism. Weak. References. [1][2][3]. Sugilite (/ˈsuːɡɪlaɪt/ SOO-gi-lyt), also known as lavulite ...
Birefringence. δ = 0.290 - 0.370. Melting point. 432.8 °C [2]. Other characteristics. Fluorescent - electric blue to blue-green ...
Birefringence. None. Pleochroism. Absent. Dispersion. None. References. [1]. Moldavite (Czech: Vltavín) is a forest green, ...
Birefringence. +0.009 (B-G interval). Pleochroism. None. Melting point. 1670 °C (β tridymite) 1713 °C (β cristobalite)[3]. ...
Birefringence. Isotropic, appears black in cross-polarized light. Pleochroism. none. Ultraviolet fluorescence. inert. ...
Birefringence. 0.004. Unpolished bloodstone. The mineral aggregate heliotrope (from Greek ἥλιος, hḗlios "Sun", τρέπειν, trépein ...
Birefringence. δ = 0.218. Pleochroism. weak. Ultraviolet fluorescence. None. References. [1][2][3]. ...
Birefringence. +0.009 (B-G interval). Pleochroism. weak, from red-brown to green-brown. ...
Birefringence. 0.008. 2V angle. 20° to 60°. Dispersion. relatively weak. Ultraviolet fluorescence. Non-fluorescent. ...
Birefringence. δ = 0.028. 2V angle. Measured: 52°. Solubility. In water. Alters to. Dehydrates in dry air. ...
David Brewster discovers stress birefringence. Rev. Robert Stirling obtains a U.K. patent for the Stirling hot air engine. ...
Its birefringence value is 0.007. It has three refractive indices which are nα=1.531 nβ=1.534 nγ=1.538. Refractive indices are ...
The change in a dimension is −11×10−6 K−1. Birefringence drops as temperature rises. It varies from 0.0076 at −150 °C down to ... 0.0067 at 0 °C and 0.0061 at 100 °C. At the lower phase transition, birefringence steps down as the temperature drops; for the ...
... and its birefringence is .025. Grandreefite, while not a valuable mineral in terms of commercial use, is useful in the sense ...
Birefringence for facetors I: what is birefringence? Archived December 14, 2013, at the Wayback Machine First published in ... "Birefringence". Sixty Symbols. Brady Haran for the University of Nottingham. The Birefringence of Thin Ice (Tom Wagner, ... Isotropic solids do not exhibit birefringence. However, when they are under mechanical stress, birefringence results. The ... or a crystal of known birefringence is added to the sample for comparison. Birefringence can be observed in amyloid plaques ...
In biochemistry, flow birefringence is a hydrodynamic technique for measuring the rotational diffusion constants (or, ... equivalently, the rotational drag coefficients). The birefringence of a solution sandwiched between two concentric cylinders is ...
Birefringence of the Transition Region. Examination of the cholesteric to high density phase transition region with the aid of ... The result is confusing images that show disorganized birefringence with a negative value for the minute structures seen ... a full-wave retardation plate was conducted to observe the sign of birefringence for this mesophase. ...
Rheo-optical measurements revealed a localized birefringence zone above a critical strain-rate in... ... Results show a steep decrease in birefringence with axial distance. Birefringence profiles determined in a direction ... Birefringence was studied with a polarization-modulation technique for dilute PS solutions (50-500 ppm) as a function of fluid ... 1999) Birefringence of Dilute PS Solutions in Abrupt Contraction Flow. In: Nguyen T.Q., Kausch HH. (eds) Flexible Polymer ...
... and lenses tends to produce birefringence in the materials. Man ... explained that birefringence is a serious problem for LCDs and ... In the pickup lens systems in CD and DVD players, birefringence increases the spot size of the laser beam, thus compromising ... Crystals Compensate for Birefringence in Polymer. Photonics Spectra. Oct 2003 Daniel S. Burgess ... LCDs use plane-polarized light, and the change to elliptical polarization due to birefringence degrades the contrast and other ...
The two independent refractive indices of anisotropic crystals are quantified in terms of their birefringence, a measure of the ... Thus, the birefringence (B, often termed d, or D) of a crystal is defined as:. B = ,nhigh - nlow, where n(high) is the largest ... Retardation (G) = thickness (t) x birefringence (B) or G = t x ,nhigh - nlow, where G is the quantitative retardation of the ... Optical Birefringence. Many transparent solids, such as glass, are optically isotropic, which means that their index of ...
The paper analyses and compares different types ofhigh-birefringence fiber loop mirror sensors using conventional and ... Recent advances in devices and applications of high-birefringence fiber loopmirror sensors are addressed. In optical sensing, ... Birefringence. The birefringence (β) of an optical fiber relates the difference in refractive indices along the fast axis (ny) ... Recent Advances in High-Birefringence Fiber Loop Mirror Sensors. Orlando Frazão 1,3,*, José M. Baptista 2,1 and José L. Santos ...
... Lochte, Annalena Antonia ... To estimate single coccolith weights, this study takes advantage of the birefringence method (Beaufort, 2005), which links the ... Gephyrocapsa oceanica, coccolith weight estimates, birefringence method, cross-polarized light, circular polarizer, dissolved ...
... Mark C. Pierce; John ... Mark C. Pierce, John Strasswimmer, Hyle Park, Barry Cense, Johannes F. de Boer, "Birefringence measurements in human skin using ... Mark C. Pierce, John Strasswimmer, Hyle Park, Barry Cense, Johannes F. de Boer, "Birefringence measurements in human skin using ... Variation in normal skin birefringence according to anatomical location is demonstrated, and discussed in relation to collagen ...
Multivariate system of polarization tomography of biological crystals birefringence networks Author(s): N. I. Zabolotna; S. V. ... Algorithms of reconstruction of parameter distributions were determined that describe the linear and circular birefringence. ...
To explore the effects of different M II stage oocytes zona pellucida birefringence on pregnancy outcome. A total of 46 couples ... HZB/low zona birefringence (LZB) group and LZB/LZB group according to different oocytes zona pellucida birefringence. ... Birefringence. Embryo Implantation / physiology*. Female. Follicle Stimulating Hormone / metabolism. Humans. Infertility, Male ... Age and FSH levels were negatively correlated with the single oocyte zona pellucida birefringence; While the LH level on the ...
This item is the full tutorial by the same authors relating to birefringence, also known as double refraction of light. It ... This item is an interactive Java simulation by the same authors on the topic of birefringence. It simulates a virtual ... Molecular Expressions: Polarized Light Microscopy - Double Refraction (Birefringence) in Iceland Spar covers the same topic as ... Molecular Expressions: Polarized Light Microscopy - Double Refraction (Birefringence) in Iceland Spar is based on Molecular ...
Tailored surface birefringence by femtosecond laser assisted wet etching Rokas Drevinskas, Mindaugas Gecevičius, Martynas ... H. Kikuta, Y. Ohira, and K. Iwata, "Achromatic quarter-wave plates using the dispersion of form birefringence," Appl. Opt. 36(7 ... H. Kikuta, Y. Ohira, and K. Iwata, "Achromatic quarter-wave plates using the dispersion of form birefringence," Appl. Opt. 36(7 ... H. Kikuta, Y. Ohira, and K. Iwata, "Achromatic quarter-wave plates using the dispersion of form birefringence," Appl. Opt. 36(7 ...
The value of birefringence is calculated for each A-scan in the PS-OCT volume using a quadrature demodulation and phase ... The resulting en face images of tissue birefringence are more useful than conventional PS-OCT B-scans in assessing the severity ... Birefringence and vascular imaging of in vivo human skin by... Proceedings of SPIE (February 16 2017) ... A technique for generating en face parametric images of tissue birefringence from scans acquired using a fiber-based ...
Vitamin C crystals, polarised light micrograph. Vitamin C, ascorbic acid, is an essential vitamin that is found in fruit and green vegetables. It is needed for the growth and maintenance of bones, teeth, skin and blood vessels. It is also a powerful antioxidant. Deficiency in vitamin C leads to scurvy, which causes bleeding gums and anaemia. Magnification: x72 when printed at 10 centimetres wide. - Stock Image C036/0910
Preliminary ellipsometric studies and tests for measuring the birefringence of electro-optic materials Author(s): Petre C. ... For this reason we endeavoured to devise and to test experimental arrangements that measure the birefringence of uniaxial ...
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ABUNDANCE; BIREFRINGENCE; FILMS; GRAIN ORIENTATION; LANTHANUM; ... Title: Superior electro-optical properties of electrically controlled birefringence mode using solution-derived La{sub 2}O{sub ... The authors demonstrate a high performance electrically controlled birefringence (ECB) mode with solution-derived La{sub 2}O{ ... Journal Article: Superior electro-optical properties of electrically controlled birefringence mode using solution-derived La{ ...
... especially molten polymers in which flow birefringence has been induced by shear stress. ... Home/Techniques/Birefringence Measurement/Flow Birefringence Flow Birefringence. Photoelastic modulators have been used to ... The laser beam is then analyzed to determine flow birefringence and/or linear dichroism characteristics of the sheared fluid. ... S.J. Johnson, P.L. Frattini and G.G. Fuller, "Simultaneous Dichroism and Birefringence Measurements of Dilute Colloidal ...
Home/Knowledge Center/Technology Primer/Birefringence Measurement Birefringence Tutorial. Birefringence occurs when an optical ... The induced birefringence may be temporary, as when the material is oscillated, or the birefringence may be residual, as may ... This phenomenon is birefringence and is exhibited to a greater or lesser degree in all anisotropic crystals. The axis along ... Birefringence is measured as the difference of indices of the refraction of the components within the material. For a light ...
... birefringence declines prior to RNFL atrophy. The purpose of this study was to examine the hypothesis that RNFL birefringence ... Axonal Birefringence Changes Following Surgical Reduction in Iop You will receive an email whenever this article is corrected, ... M. Sehi, D. S. Grewal, W. J. Feuer, W. Shi, D. S. Greenfield; Axonal Birefringence Changes Following Surgical Reduction in Iop ... Sixty-four corresponding RNFL segments were extracted from the GDxECC and OCT measurement circles and RNFL birefringence values ...
Birefringence Properties of the Central Cornea After LASIK You will receive an email whenever this article is corrected, ... Abstract: : Purpose: To determine the changes in corneal birefringence that result from ablation of collagen fibrils in the ... Using the waveplate to extinguish the image yielded values for the axis and retardance of the corneal birefringence. ... D Dursun, V Fernandez, SH Yoo, W Feuer, RW Knighton; Birefringence Properties of the Central Cornea After LASIK . Invest. ...
High-birefringence fiber loop mirror sensor using a WDM fused fiber coupler D. J. Passos, Manuel J. Marques, and Orlando Frazão ... High-birefringence fiber loop mirrors and their applications as sensors Yange Liu, Bo Liu, Xinhuan Feng, Weigang Zhang, Guang ... Liquid-level sensor with a high-birefringence-fiber loop mirror Dong Bo, Zhao Qida, Lvjun Feng, Guo Tuan, Xue Lifang, Li ... Tunable comb filters and refractive index sensors based on fiber loop mirror with inline high birefringence microfiber Wa Jin, ...
Efficient recurrence quantum entanglement distillation algorithm for quantum channels impaired by fiber birefringence. 2:42 PM- ...
Therefore, the final birefringence signal at 5 °C should be the same as before the temperature cycle.11,16 If the birefringence ... The peak birefringence was reached at 5.5 T in accordance with equation 1. This maximal birefringence value is reported in B). ... Moreover, the birefringence signal measured under a magnet field must be normalized by subtracting the mean birefringence ... Birefringence measurements are a viable and comparatively simple alternative. Analogously to NMR experiments, birefringence ...
MYC2-Activated TRICHOME BIREFRINGENCE-LIKE 37 Acetylates Cell Walls and Enhances Herbivore Resistance. Aiqing Sun, Bo Yu, Qian ... MYC2-Activated TRICHOME BIREFRINGENCE-LIKE 37 Acetylates Cell Walls and Enhances Herbivore Resistance ...
The measured birefringence showed temperature dependency and quite fit with the rate process equation. We think vessel wall ... Utility of birefringence changes due to collagen thermal denaturation rate process analysis: vessel wall temperature estimation ... The birefringence was measured by polarizing microscopic system using Brace-Koehler compensator 1/30 wavelength. ... Denaturation is able to be quantified with measured collagen birefringence value. To express the denaturation with equation of ...
While optical birefringence depends on the overall symmetry properties of a material, X-ray birefringence (when studied using ... Subsequently, a new technique called X-ray Birefringence Imaging (XBI) was developed21 to allow X-ray birefringence data to be ... The value of S is often determined by measurement of the optical birefringence (S is proportional to the birefringence). As an ... 5 While optical birefringence is widely exploited in this way, the opportunity to study birefringence of anisotropic materials ...
The aim was to determine the influence of the womans age on ZP birefringence, a sign of oocyte quality, and morphology of in- ... 30 years women (56%) in comparison with other age group (80.7%). In addition, the ZP birefringence was significantly higher in ... Home » Does womens age influence zona pellucida birefringence of metaphase II oocytes in in-vitro maturation program? ... Materials and Methods: ZP birefringence and morphology were determined in 105 retrieved oocytes from 58 women undergoing ICS1 ...
Decreased birefringence of the superficial zone collagen network in the canine knee (stifle) articular cartilage after long ... Decreased birefringence of the superficial zone collagen network in the canine knee (stifle) articular cartilage after long ... CONCLUSION: Endurance type running exercise in beagles caused a reduction in the superficial zone birefringence of the ...
"Quantifying birefringence in the bovine model of early osteoarthritis using polarisation-sensitive optical coherence tomography ... The magnitude of the birefringence was quantified using the birefringence coefficient (BRC) and statistical analysis revealed ... The magnitude of the birefringence was quantified using the birefringence coefficient (BRC) and statistical analysis revealed ... enabling the detection of tissue birefringence. Tissue birefringence is dependent on collagen fibre organisation and ...
  • This item is the full tutorial by the same authors relating to birefringence, also known as double refraction of light. (compadre.org)
  • The birefringence is often quantified as the maximum difference between refractive indices exhibited by the material. (wikipedia.org)
  • The two independent refractive indices of anisotropic crystals are quantified in terms of their birefringence , a measure of the difference in refractive index. (fsu.edu)
  • If the material has a single axis of anisotropy or optical axis, (i.e. it is uniaxial ) birefringence can be formalized by assigning two different refractive indices to the material for different polarizations. (chemeurope.com)
  • Polarizing microscopes can measure the properties of asbestos, such as refractive indices, birefringence, retardation, extinction angles, pleochroism and signs of elongation, helping in the identification of asbestos. (nikon.com)
  • The LV100ND POL/DS enables analysis of birefringence, extinction angles, signs of elongation, refractive indices, birefringence magnitudes and pleochroism of asbestos. (nikon.com)
  • Specifically, polarization properties, such as birefringence (the difference between the refractive indices of a material) and chirality (which relates to molecular asymmetry) are both under selection to create enhanced structural reflectivity. (royalsocietypublishing.org)
  • This phenomenon is birefringence and is exhibited to a greater or lesser degree in all anisotropic crystals. (hindsinstruments.com)
  • The X-ray Birefringence Imaging (XBI) technique, first reported in 2014, is a sensitive method for spatially resolved mapping of the local orientational properties of anisotropic materials. (rsc.org)
  • 4,5 While optical birefringence is widely exploited in this way, the opportunity to study birefringence of anisotropic materials using linearly polarized X-rays 6-14 has remained remarkably neglected. (rsc.org)
  • The phenomenon of X-ray birefringence is closely related to the phenomenon of X-ray dichroism, 15-19 both of which concern the interaction of linearly polarized X-rays with anisotropic materials. (rsc.org)
  • Biaxial birefringence , also known as trirefringence , describes an anisotropic material that has more than one axis of anisotropy. (chemeurope.com)
  • Birefringence analysis is the study of the anisotropic interaction of matter with light. (taorad.com)
  • Intrinsic birefringence is mainly resulting from the anisotropic properties of the molecules itself, whereas form birefringence is resulting from anisotropic polarisabilities resulting if elongated structures are present in a media with a different refraction index. (taorad.com)
  • For the positive dielectric anisotropic LCs, we have developed some high birefringence isothiocyanato tolane LC compounds with birefringence ~0.4, and super high birefringence isothiocyanato biphenyl-bistolane LC compounds with birefringence as high as ~0.7. (ucf.edu)
  • It is anisotropic and has high birefringence . (wikipedia.org)
  • BACKGROUND AND OBJECTIVE: Linear birefringence is an anisotropic property of rat tail tendon, which is largely composed of collagen. (mendeley.com)
  • In biochemistry, flow birefringence is a hydrodynamic technique for measuring the rotational diffusion constants (or, equivalently, the rotational drag coefficients). (wikipedia.org)
  • Photoelastic modulators have been used to study the properties of viscous fluids, especially molten polymers in which flow birefringence has been induced by shear stress. (hindsinstruments.com)
  • The heart of the experimental setup is a special flow cell which subjects a layer of the viscous fluid to time-dependent shear stresses and creates flow birefringence. (hindsinstruments.com)
  • The laser beam is then analyzed to determine flow birefringence and/or linear dichroism characteristics of the sheared fluid. (hindsinstruments.com)
  • Contact us for more information about flow birefringence. (hindsinstruments.com)
  • 1. A coaxial viscosimeter which permits the simultaneous determination of relative and anomalous viscosity and of flow-birefringence is described. (rupress.org)
  • Flow-anomaly and flow-birefringence are regarded as characteristic of elongated micelles and molecules. (rupress.org)
  • high-birefringence fiber. (mdpi.com)
  • Recent advances in devices and applications of high-birefringence fiber loop mirror sensors are addressed. (mdpi.com)
  • The paper analyses and compares different types of high-birefringence fiber loop mirror sensors using conventional and microstructured optical fibers. (mdpi.com)
  • The reflection and transmission characteristics of a high-birefringence fiber loop mirror (HiBi-FLM), which is composed of a standard fiber coupler and one-section or multisection high-birefringence fibers (HBFs), are analyzed and discussed in detail. (osapublishing.org)
  • Moreover, we have studied the photostability of several high birefringence LC compounds, mixtures, and LC alignment layers in order to determine the failure mechanism concerning the lifetime of LC devices. (ucf.edu)
  • The residual linear birefringence in an optical component affects its quality, especially when used in polarization related instruments. (hindsinstruments.com)
  • Hinds Instruments' photoelastic modulation technology can be applied to the measurement of linear birefringence of transparent optical materials and is used in Exicor instrumentation in patented and proprietary ways to produce unprecedented sensitivity. (hindsinstruments.com)
  • Can Linear Birefringence create elliptically polarized waves? (physicsforums.com)
  • Our goal is to show that the dynamic range and sensitivity of the linear birefringence loss of collagen during heating are sufficient for kinetic modeling of the reaction. (mendeley.com)
  • STUDY DESIGN, MATERIALS AND METHODS: The linear birefringence loss was quantified for tendon denatured via both a heated-isotonic-saline bath and a heated stage. (mendeley.com)
  • RESULTS: The data show that the loss of linear birefringence is a first-order kinetic reaction. (mendeley.com)
  • Application of the Arrhenius equation to the linear birefringence data yields the activation energy (Ea = 89 +/- 1 kcal/mole), pre-exponential coefficient (A = e130 +/- 1 s-1), enthalpy (delta H = 88 +/- 1 kcal/mole) and entropy (delta S = 197 +/- 2 cal/degree K.mole). (mendeley.com)
  • CONCLUSION: This study shows that dynamic changes in linear birefringence can be used to monitor thermally induced changes in collagen. (mendeley.com)
  • Huang, XR & Knighton, RW 2002, ' Linear birefringence of the retinal nerve fiber layer measured in vitro with a multispectral imaging micropolarimeter ', Journal of Biomedical Optics , vol. 7, no. 2, pp. 199-204. (elsevier.com)
  • To determine the changes in corneal birefringence that result from ablation of collagen fibrils in the corneal stroma by laser in situ keratomileusis (LASIK). (arvojournals.org)
  • Corneal birefringence was measured with a corneal polarimeter (Knighton & Huang, IOVS, in press) that illuminated the eye with a yellow (585 nm) light emitting diode and provided a view of the fourth Purkinje image through crossed polarizers and a variable waveplate. (arvojournals.org)
  • Using the waveplate to extinguish the image yielded values for the axis and retardance of the corneal birefringence. (arvojournals.org)
  • 1 Previous experimental investigations of corneal birefringence have not recognized the rotator component. (elsevier.com)
  • Theory shows that such a stack is optically equivalent to two optical elements in series - a polarization rotator followed by a single birefringent plate.1 Previous experimental investigations of corneal birefringence have not recognized the rotator component. (elsevier.com)
  • The influence of sodium salicylate (NaSal) concentration on the linear micelle formation in an aqueous solution of cetyltrimethylammonium bromide (CTAB) is investigated by the frequency-domain electric birefringence relaxation spectroscopy (FEE method). (elsevier.com)
  • On the ground of dielectrometry and electric birefringence data we calculated molar Kerr constants of substances dissolved in organic media of diverse polarity and polarizability under the conditions of infinite dilution. (edu.pl)
  • Rheo-optical measurements revealed a localized birefringence zone above a critical strain-rate in the immediate orifice entrance. (springer.com)
  • Mark C. Pierce , John Strasswimmer , Hyle Park , Barry Cense , Johannes F. de Boer , "Birefringence measurements in human skin using polarization-sensitive optical coherence tomography," Journal of Biomedical Optics 9(2), (1 March 2004). (spiedigitallibrary.org)
  • Variability estimates were generated for each segment using 4 pre-operative birefringence measurements. (arvojournals.org)
  • Fingerprint Dive into the research topics of 'Comparison of birefringence signals and calcium transients in voltage‐clamped cut skeletal muscle fibres of the frog. (elsevier.com)
  • Preliminary evidence exists that following experimental optic nerve injury, retinal nerve fiber layer (RNFL) birefringence declines prior to RNFL atrophy. (arvojournals.org)
  • The simplest type of birefringence is described as uniaxial, meaning that there is a single direction governing the optical anisotropy whereas all directions perpendicular to it (or at a given angle to it) are optically equivalent. (wikipedia.org)
  • For this reason we endeavoured to devise and to test experimental arrangements that measure the birefringence of uniaxial structures with the symmetry axis parallel and perpendicular to the surface. (spie.org)
  • By use of a highly sensitive method for measuring slight variations in birefringence it is shown here that a strong reversible correlation exists between rat tail tendon birefringence and temperature. (osapublishing.org)
  • The native rat tail tendon birefringence, delta n = 3.0 +/- 0.6 x 10(-3) (mean +/- std. (mendeley.com)
  • Birefringence occurs when an optical material in the path of a beam of light causes the beam to be split into two polarization components which travel at different velocities. (hindsinstruments.com)
  • Variation in normal skin birefringence according to anatomical location is demonstrated, and discussed in relation to collagen distribution at each location. (spiedigitallibrary.org)
  • Denaturation is able to be quantified with measured collagen birefringence value. (spie.org)
  • Decreased birefringence of the superficial zone collagen network in the canine knee (stifle) articular cartilage after long distance running training, detected by quantitative polarised light microscopy. (bmj.com)
  • CONCLUSION: Endurance type running exercise in beagles caused a reduction in the superficial zone birefringence of the articular cartilage, which indicates either a disorganisation or a reorientation of the superficial zone collagen network. (bmj.com)
  • Effects of M II stage oocytes zona pellucida birefringence on pregnancy outcome. (biomedsearch.com)
  • METHODS: A total of 46 couples with infertile which induced by single cause received in-vitro fertilization treatment were analyzed retrospectively, and randomly divided into the high zona birefringence (HZB)/HZB group, HZB/low zona birefringence (LZB) group and LZB/LZB group according to different oocytes zona pellucida birefringence. (biomedsearch.com)
  • Logistic regression analysis showed that factors affect M II stage oocytes zona pellucida birefringence were age, basal FSH level and the LH level on the day of HCG injection. (biomedsearch.com)
  • Does women's age influence zona pellucida birefringence of metaphase II oocytes in in-vitro maturation program? (ebscohost.com)
  • The aim was to determine the influence of the woman's age on ZP birefringence, a sign of oocyte quality, and morphology of in-vitro matured human oocytes using non-invasive polarized light (PolScope) microscopy. (ebscohost.com)
  • Conclusion: There was a positive relationship between advanced maternal age with decreased ZP birefringence and oocyte morphological quality in in-vitro matured human oocytes. (ebscohost.com)
  • An enhancement module to improve the atypical birefringence pattern using scanning laser polarimetry with variable corneal compensation. (semanticscholar.org)
  • Predictors of atypical birefringence pattern in scanning laser polarimetry. (semanticscholar.org)
  • Scanning laser polarimetry (SLP) assesses the retina nerve fiber layer (RNFL) for glaucoma diagnosis by detecting the birefringence of the peripapillary RNFL. (elsevier.com)
  • Now researchers at Keio University in Yokohama, Japan, and at Japan Science and Technology Corp. in Kawasaki have developed an approach that introduces inorganic crystals with the opposite birefringence to compensate for that of the polymer. (photonics.com)
  • The crystals properly oriented themselves to compensate for the polymer's birefringence as the polymer chains in the material oriented themselves in processing. (photonics.com)
  • They found that the addition of the crystals nearly eliminated orientational birefringence in the drawn polymer film, although it did slightly increase scattering loss, which they suggest may be reduced by employing crystals smaller than approximately 200 X 20 nm. (photonics.com)
  • Birefringence , or double refraction , is the decomposition of a ray of light into two rays (the ordinary ray and the extraordinary ray ) when it passes through certain types of material, such as calcite crystals or boron nitride , depending on the polarization of the light. (chemeurope.com)
  • While birefringence is often found naturally (especially in crystals), there are several ways to create it in optically isotropic materials. (chemeurope.com)
  • There are many birefringent crystals: birefringence was first described in calcite crystals by the Danish scientist Rasmus Bartholin in 1669. (chemeurope.com)
  • Taorad uses these anisotropies for both studying intrinsic birefringence, as observed in crystals, as well as form birefringence, as observed in tissues like bone, cartilage, brains white and even gray matter. (taorad.com)
  • Liquid crystals are a promising candidate for development of active plasmonics due to their large birefringence, low driving threshold, and versatile driving methods. (mdpi.com)
  • Single calcite crystals display an optical property called birefringence (double refraction). (rug.nl)
  • Examination of the cholesteric to high density phase transition region with the aid of a full-wave retardation plate was conducted to observe the sign of birefringence for this mesophase. (fsu.edu)
  • To account for this effect, a numerical technique has been devised to compute local birefringence (An) from experimental retardation (δ). (springer.com)
  • Retardation or retardance represents the integrated effect of birefringence acting along the path of a light beam that traverses a sample of the optical material. (hindsinstruments.com)
  • An "average" or "normalized" birefringence for a sample is sometimes computed by dividing the measured retardation magnitude by the thickness of the sample. (hindsinstruments.com)
  • the improvement which comprises at least two retardation plate devices operatively associated with said liquid crystal cell for compensating for the normal component of birefringence of said liquid crystal material, the optical axes of said retardation plate devices being parallel to the surfaces of the said retardation plate devices. (google.com)
  • To estimate single coccolith weights, this study takes advantage of the birefringence method (Beaufort, 2005), which links the interference color of calcite under polarized light with calcite thickness. (diva-portal.org)
  • Image shows birefringence interference colour range (at 30µm thickness) and does not take into account mineral colouration. (mindat.org)
  • Birefringence is resulting from the so-called intrinsic birefrigence and from the so-called form birefringence. (taorad.com)
  • The wavelength independence is consistent with a mechanism of form birefringence from thin cylindrical organelles. (elsevier.com)
  • The early large birefringence signals, related to excitation‐contraction coupling had a time course similar to that of calcium transients. (elsevier.com)
  • While the LH level on the day of hCG injection was positively correlated with the single oocyte zona pellucida birefringence. (biomedsearch.com)
  • The birefringence value of zona pellucida can affect the pregnancy outcome. (biomedsearch.com)
  • The dispersion control of birefringence by the etching procedure led to achromatic behaviour over the entire visible spectral range. (osapublishing.org)
  • Sixty-four corresponding RNFL segments were extracted from the GDxECC and OCT measurement circles and RNFL birefringence values were calculated for each segment (GDxECC retardance divided by OCT-derived RNFL thickness). (arvojournals.org)
  • A significant focal increase in retardance, RNFL thickness and birefringence occurred in 8/29 (28%), 18/29 (62%), and 8/29 (28%) patients, respectively. (arvojournals.org)
  • Focal decrease in retardance, RNFL thickness and birefringence occurred in 3/29 (10%), 3/29 (10%) and 5/29 (17%) patients, respectively. (arvojournals.org)
  • Focal improvement in peripapillary RNFL retardance, thickness and birefringence may occur in some patients following surgical IOP reduction. (arvojournals.org)
  • A detailed understanding of SLP requires an accurate value for RNFL birefringence in order to relate measured retardance to RNFL thickness, but current knowledge of this value is limited. (elsevier.com)
  • Birefringence is responsible for the phenomenon of double refraction whereby a ray of light, when incident upon a birefringent material, is split by polarization into two rays taking slightly different paths. (wikipedia.org)
  • Specifically, these phenomena relate to the way in which X-ray absorption (in the case of dichroism) and the real part of the complex refractive index (in the case of birefringence) depend on the orientation of the material relative to the direction of linear polarization of the incident X-ray beam. (rsc.org)
  • Although X-ray dichroism and X-ray birefringence give rise to different effects on the propagation of linearly polarized radiation through a material, they are related by a Kramers-Kronig transform 20 and the two phenomena depend on the same structural and symmetry properties of the material. (rsc.org)
  • Birefringence and related optical effects (such as optical rotation and linear or circular dichroism ) can be measured by measuring the changes in the polarization of light passing through the material. (chemeurope.com)
  • A birefringence microscopy technique provides structural and functional information about airway smooth muscle in healthy and mild asthmatic subjects. (sciencemag.org)
  • A new birefringence microscopy technique enables visualization and measurement of the smooth muscle cells lining the human bronchus (red). (sciencemag.org)
  • The birefringence was measured by polarizing microscopic system using Brace-Koehler compensator 1/30 wavelength. (spie.org)
  • A technique for generating en face parametric images of tissue birefringence from scans acquired using a fiber-based polarization-sensitive optical coherence tomography (PS-OCT) system utilizing only a single-incident polarization state is presented. (spiedigitallibrary.org)
  • In 37 nerve fiber bundles of 8 retinas, the average RNFL birefringence was 0.23 nm/μm before and 0.19 nm/μm after fixation, with an uncertainty of 0.01 nm/μm. (elsevier.com)
  • This paper explains the benefits of using fluorinated acrylates in achieving low-loss waveguides with low birefringence. (elsevier.com)
  • 2.3.5 Birefringence in thin-film waveguides. (barnesandnoble.com)
  • While optical birefringence depends on the overall symmetry properties of a material, X-ray birefringence (when studied using an X-ray energy corresponding to an absorption edge of an element in the material) is sensitive to the local orientational properties of individual molecules and/or bonds. (rsc.org)
  • The ability of X-ray birefringence to yield insights into molecular orientational properties was first exploited 10 for accurate determination of bond orientations and for establishing changes in molecular orientational distributions associated with order-disorder phase transitions in solids. (rsc.org)
  • We demonstrate that tissue structure, birefringence, and blood flow can be imaged simultaneously by use of techniques of polarization-sensitive optical coherence tomography and phase-resolved optical Doppler tomography. (osapublishing.org)
  • In many scientific disciplines, the phenomenon of optical birefringence 1 is used as a basis for studying structural anisotropy of materials through the use of the polarizing optical microscope, 2,3 including the widespread application of this technique in the characterization of liquid-crystalline phases. (rsc.org)
  • This phenomenon is totally different from the loss of birefringence that results from a denaturation process. (osapublishing.org)
  • At this point, the storage modulus (G′) reached a plateau, and the birefringence underwent a stepwise increase, thus suggesting a percolative phenomenon. (aalto.fi)
  • Applying an electric field can induce molecules to line up or behave asymmetrically, introducing anisotropy and resulting in birefringence. (chemeurope.com)
  • The characteristic features of birefringence and calcium transients were compared in voltage‐clamped cut skeletal muscle fibres: Birefringence signals were measured by introducing crossed polarizers above and below the fibres (+/‐ 45 degrees to the fibre axis) and using light of 790 nm. (elsevier.com)
  • Photograph of calcite displaying the characteristic birefringence optical behaviour. (rug.nl)
  • abstract = "We show that composite hydrogels comprising methyl cellulose (MC) and cellulose nanocrystal (CNC) colloidal rods display a reversible and enhanced rheological storage modulus and optical birefringence upon heating, i.e., inverse thermoreversibility. (aalto.fi)
  • Indeed, the first definitive demonstration of X-ray birefringence was reported only recently 10 for a model material that was shown to exhibit essentially ideal birefringence behaviour at X-ray energies near the Br K-edge. (rsc.org)
  • The purpose of this study was to examine the hypothesis that RNFL birefringence improves following surgical reduction of IOP. (arvojournals.org)
  • The authors demonstrate a high performance electrically controlled birefringence (ECB) mode with solution-derived La{sub 2}O{sub 3} films at various molar concentrations. (osti.gov)
  • All samples shown are unstained and the colors are representing one of the properties of the birefringence! (taorad.com)
  • Birefringence signals recorded at different voltages along the strength‐duration curve for contraction threshold had the same amplitudes and similar time constants for the falling phase comparable to the properties of the calcium transients. (elsevier.com)
  • Consequently the voltage‐dependent properties of birefringence and calcium transients and their responses to caffeine and dantrolene treatment are nearly the same. (elsevier.com)
  • Birefringence is an intrinsic property of many optical materials, and may also be induced by external forces applied to the material. (hindsinstruments.com)
  • Birefringence can also arise in magnetic , not dielectric, materials, but substantial variations in magnetic permeability of materials are rare at optical frequencies. (chemeurope.com)
  • LCDs use plane-polarized light, and the change to elliptical polarization due to birefringence degrades the contrast and other visual characteristics of the displays. (photonics.com)
  • It is also important to point out that some materials may be isotropic at some wavelengths of light and exhibit birefringence characteristics at others. (hindsinstruments.com)
  • The result is confusing images that show disorganized birefringence with a negative value for the minute structures seen adjacent to the high density phase. (fsu.edu)
  • In addition, most of the natural variants had altered Pontamine Fast Scarlet 4B staining of cellulose and significantly reduced birefringence of crystalline structures. (frontiersin.org)
  • In addition, these dopants increase the birefringence and reduce the viscosity of the host LCs which leads to a faster response time. (ucf.edu)
  • We think vessel wall temperature is able to be estimated using the birefringence changes due to thermal denaturation. (spie.org)
  • Below the threshold temperature leading to denaturation, an increase in temperature is systematically accompanied by a reversible increase in birefringence (0.25% °C -1 ). (osapublishing.org)
  • Birefringence is the optical property of a material having a refractive index that depends on the polarization and propagation direction of light. (wikipedia.org)
  • It includes basic concepts, microscope configuration, history of the technique and its applications, and full tutorials on optical birefringence and polarization of light. (compadre.org)
  • For a light beam that has been split into two components by a material, birefringence is the difference of the indices of refraction of the components within the material. (hindsinstruments.com)
  • Congo red dye intercalates between the folds and, when observed under polarized light, causes birefringence. (chemeurope.com)
  • Through our testing programs - including fundamental tests such as Gloss, Haze, Birefringence and Ultra-Violet and Visable (UV/VIS) light absorption and transmission - Intertek can help you to optimise production in order to achieve optical property specifications. (intertek.com)
  • Discussion of birefringence, Brewster's angle, and various forms of polarized light. (microscopyu.com)
  • Discover how specimen birefringence is affected by the angle of polarizer when observed in a polarized light microscope. (microscopyu.com)
  • An amyloid fibril must exhibit affinity for Congo red and with green, yellow or orange birefringence when the Congo red-stained deposits are viewed with polarized light. (nih.gov)
  • The resulting en face images of tissue birefringence are more useful than conventional PS-OCT B-scans in assessing the severity of tissue damage and in localizing the spatial extent of damage. (spiedigitallibrary.org)