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Gourlay J - - 1993
The Hadamard transform is an example of a matrix transform that allows images to be represented in terms of orthogonal basis functions with binary-valued matrix elements. Such basis functions can be displayed on binary amplitude modulating ferroelectric-liquid-crystal-over-silicon spatial light modulators, permitting novel, real-time, and high-speed implementation of the transform on ...
Thorsrud B A - - 1993
A micro-fiberoptic methodology has been developed for non-invasive, real time measurement of endogenous pyridine nucleotide fluorescence from the surface of the visceral yolk sac (VYS) in intact, viable rat conceptuses. Gestational day (GD) 10-12 conceptuses are maintained in a customized perifusion system, which allows for control of oxygenation, as well ...
Conway P J - - 1993
The purpose of this study was to measure the forces exerted during spinal manipulative therapy of the thoracic spine simultaneously with corresponding cavitation signals. Forces were measured using a thin, flexible pressure mat which was placed on patients over the contact area between doctor and patient. Cavitation signals were measured ...
Lakowicz J R - - 1993
The technique of 10 GHz frequency-domain fluorometry was used to resolve the complex picosecond intensity and anisotropy decays of the tyrosyl emission of [Leu5] enkephalin. Enhanced resolution of anisotropy decay was obtained by using acrylamide quenching of the tyrosyl fluorescence and global analysis of the frequency-domain anisotropy data obtained with ...
Grissom C B - - 1993
Glycerol stabilizes cyanocob(III)alamin (vitamin B12) against anaerobic photolysis by a high-intensity UV light source or a low-intensity fluorescent light source. The likely mechanism for stabilization by viscosigens is a decrease in diffusion and an enhancement of radical-pair recombination. Glycerol (25% or greater) stabilizes therapeutic doses of vitamin B12 in single-dose ...
Harris G. C. - - 1993
When spinach (Spinacia oleracea) leaf discs were incubated in a dark anaerobic environment, the chlorophyll fluorescence yield was much increased relative to the aerobic control. Occasionally, the fluorescence yield of the darkened anaerobic samples approached 80% of the maximum fluorescence. The anaerobic incubation period also induced in a leaf disc ...
Boshouwers F M - - 1993
1. The influence of fluorescent and incandescent artificial lighting in a 16L:8D day/night schedule on number and intensity of movements, and on total, resting and activity-related energy expenditure was investigated. 2. Fluorescent light showed the same positive correlation between light intensity and physical activity at all activity levels as was ...
Wirth M J - - 1993
Frequency-domain fluorometry relies on the measurement of the phase and amplitudes of the Fourier components of the time-dependent fluorescence signal. Experimental results that show that a conventional photomultiplier is subject to intensity-dependent phase shifts are presented. The measurements indicate that this is a problem well below the maximum linear current ...
Broglia M - - 1993
Remote sensing of the health status of vegetation should be possible by using UV laser-induced fluorescence; nevertheless, the molecular origin of the leaf blue-green fluorescence emission is still unknown. In order to investigate possible relations of this fluorescence to the photosynthetic apparatus, we looked for its intensity changes after the ...
Wilson D A - - 1993
The effect of light spectral quality on the growth of in vitro nodal cuttings of potato (Solanum tuberosum L.) cultivars Norland, Superior, Kennebec, and Denali were examined. The different light spectra were provided by Vita-Lite fluorescent (VF) (a white light control), blue fluorescent (BF), red fluorescent (RF), low-pressure sodium (LPS), ...
Srinivas S P - - 1992
A microscope has been modified to a confocal spatially scanning fluorometer so that the concentration profile of a fluorophore across an isolated cornea can be measured. A slit of light is focused through one half of the objective to excite fluorescence. A confocal slit is placed at the image-plane of ...
Wang P M - - 1992
In anesthetized, paralyzed, supine rabbits (3-4 kg) during apnea, we injected fluorescent dye or fluorescent microspheres (2 or 6 microns diam) into the dependent pleural space and observed the arrival and movement of the dye or microspheres at superior regions. Injection was through a rib capsule located in the dependent ...
Kent P F - - 1992
1. Fluorescence changes in the dye (WW 781) were monitored at 100 contiguous sites in a 10 x 10-pixel array on the bullfrog and salamander olfactory mucosas every 10 ms in response to odorous stimuli. The odorants were d-limonene, butanol, and amyl acetate, each presented at two concentrations with a ...
Brolin S E - - 1992
Improved bioluminescence analysis of pyridine nucleotides has been designed based on the fact that the luminescence intensity expresses the velocity of the light formation. The bacterial luciferase system is, in principle, composed of two reactions with two different velocities, one for energy supply by the oxidation of NAD(P)H and the ...
Boshouwers F M - - 1992
1. The influence of the flicker frequency on physical activity and energy expenditure of broilers was studied using commercially available high-frequency (HF) and low-frequency (LF) fluorescent lamps in a 23L:1D lighting schedule. 2. Broilers were reared under and adapted to HF. They were alternately subjected to HF and LF during ...
Brandes R - - 1992
Fluorescence spectroscopy of beating hearts has been used previously to measure intracellular regulators of function. Unfortunately, heart motion could introduce a spurious motion artifact (MA), influencing the measured fluorescence intensity ("signal"). To suppress MA, a ratio (or difference) has been calculated previously between the signal and an intensity reference detected ...
James T W - - 1992
The eyespots in cells of streptomycin-bleached strains and of dark-grown cultures of Euglena gracilis, were examined by means of fluorescence microscopy and microspectrophotometry. When viewed with light in the region of 380-500 nm, the stigma appeared as a dark spot. Adjacent to this was a second spot, not seen with ...
Bielski R J - - 1992
The principles of photobiology suggest that the antidepressant effect of phototherapy depends on the dose and spectrum of light. We investigated the effect of spectrum by comparing two broad spectrum fluorescent light sources with different spectral distributions. In a crossover design, 11 patients with seasonal affective disorder (SAD) were treated ...
Robinson J - - 1992
The lighting environment where the baby born prematurely is placed is different from that experienced in utero. As early exposure to light may affect the immature visual system we have attempted to quantify the neonatal ocular light dose. Lighting surveys performed in 7 neonatal units (NNUs) suggested that mean unit ...
Ben-Sasson S A - - 1992
While being a relatively rare disease, acute lymphocytic leukemia (ALL) is the leading form of cancer in children in the developed world today. ALL sharply peaks in incidence at ages three to four years. In the United States there have been persistent, unexplained increases in incidence of ALL in the ...
Ashwood-Smith M J - - 1992
5-geranoxypsoralen (Bergamottin) does not photosensitize bacteria or a bacterial virus. It does, however, photosensitize mammalian cells in tissue culture. Irradiation with either black light (300-400 nm) or fluorescent ceiling lights produced at least four photobiologically active degradation products, the chemical nature of which still remains to be elucidated. Prolonged exposure ...
Nuboer J F - - 1992
1. Many poultry houses are illuminated by fluorescent lamps which produce discontinuous illumination with a frequency of either 100 or 120 Hz. 2. This study investigated whether domestic fowls perceive this discontinuity as flicker by training two Leghorn hens to choose between a continuous and a discontinuous light, all other ...
Zuclich J A - - 1992
Irradiation of the primate lens by near-ultraviolet wavelengths results in a blue fluorescence, which can be an intraocular source of veiling glare. This study quantitated the fluorescence intensity as a function of exciting intensity and wavelength. As the exciting wavelength was increased from 360 to 430 nm, the decreasing fluorescence ...
Anholt H - - 1992
CaD2 mammary carcinomas transplanted into the feet of mice were treated with tetrasulfonated phthalocyanine (AlPcS4) and laser light at 680 nm. A light dose of 135 J/cm2 was either given as continuous radiation (15 min) or fractionated with 15 s exposure, 15 s darkness, 15 s exposure and so on ...
Hill W A - - 1992
Among the crops selected by the National Aeronautics and Space Administration for growth in controlled ecological life support systems are four that have subsurface edible parts -- potatoes, sweet potatoes, sugar beets and peanuts. These crops have been produced in open and closed (recirculating), solid media and liquid, hydroponic systems. ...
Bhatia J - - 1991
Toxic products are formed when tryptophan is irradiated with light in the presence of photosensitizers such as riboflavin. In order to further investigate this phenomenon, solutions of tryptophan (48 mumol.mL-1) were irradiated with broad spectrum fluorescent light in the presence or absence of riboflavin (0.01 mg.mL-1). Solutions of riboflavin were ...
Barcay S J - - 1991
Computerized moving-image analysis measured the influence of starvation and lighting conditions on the locomotor activity of the German cockroach, Blattella germanica (L.). Starvation increased the distance traveled, velocity, and the proportion of time in motion of adult males and last instars but did not increase adult female movement. For females, ...
Straight R C - - 1991
Laser and fluorescence light distributions with applications for photodynamic therapy were measured in mouse tumors using a non-invasive electronic optical imaging system. The system consists of a liquid-nitrogen-cooled, charge-coupled-device (CCD) array camera under computer control with 576 x 384 detection elements having dimensions of 23 microns x 23 microns. The ...
Mohanty N - - 1991
The impact of dark NH(4) (+) and NO(3) (-) assimilation on photosynthetic light harvesting capability of the green alga Selenastrum minutum was monitored by chlorophyll a fluorescence analysis. When cells assimilated NH(4) (+), they exhibited a large decline in the variable fluorescence/maximum fluorescence ratio, the fluorescence yield of photosystem II ...
Peterson R B - - 1991
The responses of minimal and maximal fluorescence yields of chlorophyll a to irradiance of actinic white light were determined by pulse modulated fluorimetry in leaf discs from tobacco, Nicotiana tabacum, at 1.6, 20.5, and 42.0% (v/v) O(2). Steady-state maximal fluorescence yield (F(m)', measured during a saturating light pulse) declined with ...
Fork D C - - 1991
The brown alga Macrocystis pyrifera (giant kelp) was studied by a combination of fluorescence spectroscopy at 77 kelvin, room temperature modulated fluorimetry, and photoacoustic techniques to determine how light energy is partitioned between photosystems I and II in states 1 and 2. Preillumination with farred light induced the high fluorescence ...
Zieger M A - - 1991
Cytotoxicity resulting from the interaction of fluorescent light from a flow hood with Hepes-buffered cell culture medium at room temperature was demonstrated. Toxicity was prevented by keeping both cells (V79 Chinese hamster) and medium shielded from direct fluorescent light ("dark conditions") or by supplementing the medium with 10 micrograms/ml catalase; ...
Larsen M - - 1991
Front-face fluorometry of the axial fluorescence profile of the lens is influenced by attenuation of light along the optical pathways leading to and from the detection volume. The resulting distortion is evident when the curve is compared with the intrinsic profile that can be recorded by direct measurement on the ...
Balter A - - 1991
The loss of transparency of the ocular lens is caused by the increase of light scattering as a result of structural changes and by the increased absorption of the visible light due to the accumulation of pigments. Following light absorption, these pigments undergo non-radiative and radiative (luminescence) processes which can ...
White E H - - 1991
The 5-methyl analog of firefly oxyluciferin, two isomeric O-methyl ether derivatives of it and an O,O'-dimethyl ether derivative were synthesized and their UV absorption and fluorescence emission spectra were determined. Comparisons of the emission data with the emission wavelength in bioluminescence indicate that the mono-anions of firefly oxyluciferin are candidates ...
Palmqvist K - - 1990
Cells of the unicellular green algae Chlamydomonas reinhardtii were grown in high dissolved inorganic carbon (DIC) concentrations (supplied with 50 milliliters per liter CO(2)[g]) and transferred to low DIC concentrations (supplied with </= 100 microliters per liter CO(2)[g]). Immediately after transfer from high to low DIC the emission of photosystem ...
Andersen H J - - 1990
The quality of wild salmon and farmed rainbow trout from aquaculture, both packed in transparent vacuum-skin packaging, was followed during storage for 6 months in an illuminated freezer cabinet (product temperature -17 degrees C, half of the packs protected against light, and half of the packs fully exposed to light), ...
Somersalo S - - 1990
The role of high light stress in a natural environment was studied on spinach plants (Spinacia oleracea L. cv. Wolter) grown in the field during the winter season. Fluorescence induction (at 293 K and 77 K) of leaves was used to characterize the stress effects. Night frost with minimum temperatures ...
Hazell J - - 1990
Under three types of artificial lighting 24 women with chronic agoraphobia and 24 female control subjects assessed their mood and bodily symptoms, and their heart rate was measured. One of the three types of lighting was incandescent. The other two were fluorescent, one pulsating in the conventional manner 100 times ...
Ogren E - - 1990
The effect of drought on the photosynthetic apparatus of leaves of Salix sp. was studied by measurements of the induction of chlorophyll fluorescence and the capacity for O(2) evolution. Using a multivariate analysis, a model was developed that could predict the degree of drought stress from the data of fluorescence ...
McGrath H H - - 1990
Fluorescent light emitted from cool white tubular fluorescent lamps covered with standard acrylic lids decreased autoimmunity and enhanced immunity in the New Zealand Black/New Zealand White F1 hybrid female (B/W) mouse model of systemic lupus erythematosus (SLE). Thirty-three weeks of daily cool white fluorescent light exposure significantly decreased anti-ds DNA ...
Van Raalte J - - 1990
A portable system that uses fluorescence stimulated by visible light to identify doxorubicin contamination on skin and surfaces was studied. When activated by violet-blue light in the 465-nm range, doxorubicin fluoresces, emitting orange-red light in the 580-nm range. The light source to stimulate fluorescence was a slide projector with a ...
Xu J - - 1990
Bacterial isolates of the genus Xenorhabdus were shown to be extremely sensitive to photoproducts produced in a number of common media irradiated by fluorescent light. Two forms of toxic oxygen, hydrogen peroxide and superoxide radical, were produced in the media upon exposure to fluorescent light. The addition of pyruvate or ...
Giammanco S - - 1990
Effects of different conditions of environmental lighting on the appearance of the muricidal behaviour in male Wistar rats have been studied. The animals were kept under different conditions of environmental lighting: 1) natural day light alternated with the dark of the night; 2) sodium, continuous light emitted by a sodium ...
Andrews J J - - 1990
Breathing circuit cannisters containing functional CO2 absorbent are critical to prevent rebreathing CO2 during general anesthesia using closed or semiclosed breathing systems. Ethyl violet is the indicator dye added to Sodasorb to indicate impending exhaustion of the absorbent. A case of CO2 rebreathing due to failure of ethyl violet indicator ...
Fattorossi A - - 1990
Oxidative metabolic burst of activated human polymorphonuclear leukocytes (PMN) is most commonly investigated in clinical practice by evaluating nitroblue tetrazolium (NBT) reduction at the single cell level. Reduced NBT precipitates where the redox reaction has taken place and can be visualized as PMN-associated dark blue granules of formazan in light ...
Ruth B - - 1990
The scattering coefficient of yellow spruce needles exceeds that of green needles by a factor of 2, whereas the fluorescence efficiency is approximately equal for both needle colours. As shown by the angular distribution the fluorescence light is diffusely emitted. However, the scattered light consists of a diffuse and a ...
Leighton A T - - 1989
This study consisted of two experiments: the first was conducted with Large White turkey males during the spring and summer (experiment 1) and the second during the autumn and winter (experiment 2). When 56 d of age, the birds were assigned to light-controlled pens and exposed to continuous illumination. Light ...
Demmig-Adams B - - 1989
When leaves of a mangrove, Rhizophora mangle, were exposed to an excess of light at chilling temperatures, synthesis of zeaxanthin through violaxanthin de-epoxidation as well as nonphotochemical fluorescence quenching were markedly reduced. The results suggest a protective role of energy dissipation against the adverse effects of high light and chilling ...
Demmig-Adams B - - 1989
Intact attached sun leaves of Helianthus annuus and shade leaves of Monstera deliciosa and Hedera helix were used to obtain light response curves of CO(2) uptake, the content of the carotenoid zeaxanthin (formed by violaxanthin de-epoxidation), as well as nonphotochemical quenching (q(NP)), and the rate constant of radiationless energy dissipation ...
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