In this study we have evaluated the use of blue light (peak at 415 nm) and a mixed blue and red light (peaks at 415 and 660 nm) in the treatment of acne vulgaris. One hundred and seven patients with mild to moderate acne vulgaris were randomized into four treatment ...

BACKGROUND: Monitoring strategies have been developed to address the issue of detecting postoperative free flap ischemia in an effort to permit intervention and flap salvage. No one existing noninvasive method has been widely accepted in a clinical setting. Green light photoplethysmography (GLP) uses a diode to transmit green light into ...

We report here a comparative analysis of the effect of blue (450 nm), red (660 nm), and white light (400-700 nm) on the protein profile of cyanobacteria Synechococcus sp. PCC 7942. In vivo labeling of cells with [(35)S] methionine and their subsequent analysis by two-dimensional gel electrophoresis (2-DGE) showed that ...

The light-induced intracellular relocation of chloroplasts was examined in red-light-grown protonemal cells of the moss Physcomitrella patens. When irradiated with polarized red or blue light, chloroplast distribution in the cell depended upon the direction of the electrical vector (E-vector) in both light qualities. When the E-vector was parallel to the ...

Persistent holograms are recorded with green light in LiNbO(3) crystals doped with Mn and Fe. The recording sensitivity is 20 times better than that obtained by recording with red light. Partial loss of persistence is caused by using green light for recording.

Nest box choice experiments were carried out outside the breeding season on adult silver and blue fox vixens with no previous permanent nest box experience. Nest boxes were varied in height of placement, number of rooms, presence of entrance room or platform and light conditions. Only one parameter was varied ...

Blue light-stimulated stomatal opening in detached epidermis of Vicia faba is reversed by green light. A 30 s green light pulse eliminated the transient opening stimulated by an immediately preceding blue light pulse. Opening was restored by a subsequent blue light pulse. An initial green light pulse did not alter ...

Magnetic compass orientation in birds is based on light-dependent processes, with magnetoreception being possible only under light containing blue and green wavelengths. To look for possible intensity-dependent effects we tested Australian silvereyes during autumn migration under monochromatic green light (565 nm) produced by light-emitting diodes at various light levels. At ...

The ultraviolet action spectrum for stomatal opening was measured using epidermal peels from leaves of broad bean (Vicia faba). The spectrum was calculated from hyperbolic fluence response curves using 11 wavelengths ranging from 275 to 459 nm. The action spectrum exhibits a major peak at approximately 280 nm and a ...

We compared the role of the red-green, blue-yellow, and luminance post-receptoral mechanisms in the perception of density. The task requires the comparison of densities between two stimuli composed of oriented bandpass elements, pseudo-randomly scattered across an area of constant size. The perception of density differences was measured by a temporal ...

We investigated female mate choice on the basis of visual cues in two populations of Dendrobates pumilio, the strawberry poison frog, from the Bocas del Toro Archipelago in Panama, Central America. Mate choice experiments were carried out by presenting subject females of each of two morphs of this species (orange ...

Unicellular green algae of the genus Dunaliella, similar to higher plants, respond to light stress by enhanced de-epoxidation of violaxanthin and accumulation of Cbr, a protein homologous to early light inducible proteins (Elips) in plants. These proteins belong to the superfamily of chlorophyll a/b binding proteins. Two Dunaliella strains, D. ...

Two spiro[1,2-dioxetane-3,6'-benzo(c)chromene]s bearing a t-butyldimethylsiloxy as a trigger at the 10'- or 2'-position were synthesized. On treatment with tetrabutylammonium fluoride in DMSO at 25 degrees C, the 10'-siloxyspiro[1,2-dioxetane-3, 6'-benzo(c)chromene] decomposed rapidly to afford a flash of blue light. The CIEEL decay of this spirochromenedioxetane was also induced by basic silica ...

At reproductive onset the marine green alga Acetabularia acetabulum (L.) P.C. Silva redirects growth from vertical elongation of the axis of the plant to lateral expansion of a disk-shaped reproductive structure, the "cap." We used amputation to synchronize cap initiation and to facilitate investigation of the light requirements during amputation-induced ...

Pulping of blue agave waste, from the production of tequila, was evaluated by both chemical and biomechanical pulping processes. Two conventional and two organosolv systems were used to pulp the agave waste under a standard set of conditions. The soda-ethanol process was superior in terms of delignification and pulp properties ...

The reflective properties of different types of dinoflagellate eyespots were investigated using confocal laser scanning microscopy in the epireflection contrast mode. Although the eyespots studied differed with respect to localization (cytosol or plastid) and organization of the globule layer(s), all types effectively absorbed and reflected blue-green laser light (principal lines ...

Holograms have been recorded in congruent LiTaO(3):Fe with continuous-wave laser light by use of a two-step process. Blue gating light (lambda=488 nm) sensitizes the crystals for holographic recording with red light (lambda=660 nm) of a diode laser. Refractive-index changes of as much as 1.0x10(-5) are achieved for intensities of the ...

The Arabidopsis mutant npq1, which cannot accumulate zeaxanthin because of a defective violaxanthin deepoxidase, was used to investigate the role of zeaxanthin in the stomatal response to blue light. Neither dark-adapted nor light-treated guard cells or mesophyll cells of the npq1 mutant contained detectable zeaxanthin. In contrast, wild-type guard cells ...

Violet-blue light is toxic to mammalian cells, and this toxicity has been linked with cellular production of H2O2. In this report, we show that violet-blue light, as well as UVA, stimulated H2O2 production in cultured mouse, monkey, and human cells. We found that H2O2 originated in peroxisomes and mitochondria, and ...

Photolyases and blue light receptors belong to a superfamily of flavoproteins that make use of blue and UVA light either to catalyze DNA repair or to control development. We have isolated a DNA photolyase gene (phr1) from Trichoderma harzianum, a common soil fungus that is of interest as a biocontrol ...

This Landsat scene shows the city of Beijing, looking northward. The main city airport is visible in the foreground. The Landsat data is shown with shortwave infrared (TM Band 5) displayed as red, near infrared (TM Band 4) as green, and visible green (TM Band 2) as blue. Reddish tone ...

This scene shows a 17-18 mile square area in central Oregon in the Willamette National Forest after forest fires burned through the area in the summer of 1996. The lake in the center of the image is Waldo Lake, located near the Pacific Crest in the Cascade Range. The mountain ...

OBJECTIVE: To better characterize the properties of chromatic VEPs to onset-offset of red-green and blue-yellow equiluminant patterns, and establish normative values for a set of stimuli able to elicit robust and reliable responses, suitable for the clinical application. METHODS: Chromatic VEPs have been recorded (Oz lead) from 28 normal subjects ...

Light-induced absorbance changes (LIACs), which are associated with early photochemical events of blue-light transduction, were detected in growing zones of Phycomyces sporangiophores. The novel LIACs meet all the essential requirements for a spectrophotometric photoreceptor assay which was previously unavailable for blue-light receptors (cryptochromes). In-vivo absorption spectra of growing zones were ...

Chlamydodon mnemosyne, a brackish-water ciliate which feeds on cyanobacteria, is capable of sensing the direction of light. Cells are negatively phototactic in the well-fed state and tend to swim towards the light source when mildly starved. Severely starved cells normally fail to show phototactic responses. An autofluorescent substance, which is ...

We previously reported that the arteriolar input in window chamber tumours is limited in number and is constrained to enter the tumour from one surface, and that the pO2 of tumour arterioles is lower than in comparable arterioles of normal tissues. On average, the vascular pO2 in vessels of the ...

Coleoptile tip is a blue-light sensitive tissue possessing a "blue light receptor" which, upon activation, elicits a signal cascade resulting in phototropic curvature of the coleoptile. In this context, the nature of the photoreceptors and the exact mechanism through which the photoreceptors transduces the signal across the membrane are not ...

PURPOSE: To experimentally clarify the processes of the changes induced by blue light directly on the retinal pigment epithelium (RPE) before the formation of phagosomes or the accumulation of lipofuscin. METHODS: We developed a new experimental method in which primary cultured cells of very young pigmented rats were exposed to ...

In natural habitats Marsilea quadrifolia L. produces different types of leaves above and below the water level. In aseptic cultures growth conditions can be manipulated so that leaves of the submerged type are produced continuously. Under such conditions the application of either blue light or an optimal concentration of abscisic ...

We investigated the manner in which the outputs of the three postreceptoral mechanisms (red-green, blue-yellow and luminance) combine to determine contrast threshold. We used a subthreshold summation paradigm to test whether the combination of the postreceptoral mechanism outputs could be described by a probability summation model which assumes stochastic independence ...

Artificial illumination, including light quality, is crucial in modem broiler management. In the present study, a new, highly efficient, monochromatic light system has been developed for broilers. One hundred and eighty male broiler chicks (Anak) were divided into four light treatment groups (n = 45) in three replicates each. All ...

Analysis of acoustic signals recorded from the U.S. Navy's SOund SUrveillance System (SOSUS) was used to detect and locate blue whale (Balaenoptera musculus) calls offshore in the northeast Pacific. The long, low-frequency components of these calls are characteristic of calls recorded in the presence of blue whales elsewhere in the ...

Chicks exposed to light during late foetal life experience stimulation of the right eye only and, in consequence, develop asymmetries of the crossed visual projections from thalamus to forebrain and differences in performance of some visual tasks when using the right or left eye. The present study compared dark- and ...

High intensity light-emitting diodes (LEDs) are being studied as possible light sources for the phototherapy of hyperbilirubinemic neonates. These power-efficient, low heat-producing light sources have the potential to deliver high intensity light of narrow wavelength band in the blue-green portion of the visible light spectrum, which overlaps the absorption spectrum ...

We have demonstrated highly efficient frequency doubling of femtosecond pulses in a thick, noncritically phase-matched KNbO(3) crystal under conditions of large group-velocity mismatch. At low power we observed a slope efficiency of ~300% nJ (-1) for harmonic conversion, and at higher powers we generated 170 mW of second-harmonic blue output ...

A materially-closed aquatic ecosystem (microcosm) was developed. The microcosm contained two families of green algae and blue-green alga as primary producers, protozoa, two species of rotifers and oligochaetes as consumers, and bacteria as decomposers. The microcosm could be readily replicated. It was confirmed the population densities of each organism were ...

Ovarian follicular kinetics and gravimetric changes in the ovary and oviduct were studied in intact, blinded (BL), and parietal shielded (PS) skipper frog Rana cyanophlyctis exposed to different light spectra. The gonadosomatic index (GSI) increased (P < 0.01) in intact and PS frogs, held in green, yellow, and red light. ...

BACKGROUND: Clinical evidence of injury to the retinal pigment epithelium is an important feature of age-related macular degeneration, but the mechanism of this injury is unknown. Blue-light-dependent activation of the blood-borne photosensitizer protoporphyrin IX is known to produce free radicals which may damage cells and tissues. This study was undertaken ...

Photocurrents from purple membrane suspensions of D85N BR mutant adsorbed to planar lipid membranes (BLM) were recorded under yellow (lambda > 515 nm), blue (360 nm < lambda < 420 nm) and white (lambda > 360 nm) light. The pH dependence of the transient and stationary currents was studied in ...

Blue photons are energetically expensive so the most energy-efficient lamps contain the least blue light. Blue photons are not used efficiently in photosynthesis, but blue light has dramatic effects on plant development. We studied the growth and development of soybean, wheat, and lettuce plants under high-pressure sodium and metal halide ...

As part of NASA's Advanced Life Support Program, the Breadboard Project at Kennedy Space Center is investigating the feasibility of using crop plants in bioregenerative life support systems (BLSS) for long-duration space missions. Several types of electric lamps have been tested to provide radiant energy for plants in a BLSS. ...

Wavelength sensitivity was measured in the guppyfish by means of optomotor responses to a special apparent-motion display. A set of red and green bars appeared to humans to move to the left if red was darker than green, but to the right if red was lighter than green. At equiluminance ...

Cucumbers (Cucumis sativus L. cv. Naoyosi) were grown hydroponically at air temperatures of 28/24 degrees C (D/N) and photosynthetic photon flux (PPF) of 300 micromoles m-2 s-1, in a walk-in type growth cabinet equipped with 3-band fluorescent lamps. Plants were subjected to supplemental blue lighting applied daily just before the ...

Two experiments were conducted to investigate whether manipulating the wavelength and intensity of light could be used to increase activity and reduce locomotion disorders in meat chickens. The first experiment examined the effects of wavelength and intensity of light on bird activity. Male (n = 60) and female (n = ...

The fungus Neurospora crassa has been shown to be a paradigm for photobiological, biochemical, and genetic studies of blue light perception and signal transduction. Several different developmental and morphological processes of Neurospora are regulated by blue light and can be divided into early and late blue light responses. The characterization ...

The filamentous fungus Neurospora crassa is an excellent paradigm for the study of blue light signal transduction. The isolation and characterization of the genes for two central regulators of the blue light response, white collar-1 and white collar-2, have begun to shed light on the mechanism of blue light signal ...

Dark recovery of blue light-induced in vitro phosphorylation in oat (Avena sativa L.) seedlings after in vivo preirradiation with blue light revealed different recovery kinetics for the coleoptile base and tip. Although, in both cases, maximum in vitro phosphorylation was observed 90 min after in vivo blue light treatment, the ...

The aim of this study was to compare red (652 nm) and green (514 nm) light for photodynamic therapy (PDT) of the peritoneal cavity with emphasis on light distribution and toxicity. Red-light PDT was limited by intestinal toxicity and it was hypothesized that less penetrating green light would allow higher ...

Protoplasts isolated from red-light-grown maize (Zea mays L.) coleoptiles shrank transiently upon brief exposure (e.g. 30 s) to blue light under background irradiation with red light. The maximal volume reduction (about 4% at a saturating fluence) occurred about 5 min after blue-light stimulation. The response was prevented by the anion-channel ...

Unidirectional blue light directs the rhizoid-thallus axis in the apolar zygotes of Fucus and Pelvetia. Here, it is shown that blue light (but not red light) increased cyclic GMP levels of Pelvetia zygotes by about a factor of 2. When the increase in cyclic GMP was blocked by a guanylyl ...