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Thayer Zaneta M - - 2014
Skin color has been proposed to contribute to race-based health disparities in the United States because of differences in ultraviolet (UV) light-induced vitamin D synthesis. The prediction of this hypothesis, herein named the UVD hypothesis, is that racial disparities in health outcomes are correlated with UV light availability. This paper ...
Shell Thomas A - - 2013
Although the corrin ring of vitamin B12 is unable to efficiently absorb light beyond 550 nm, it is shown that commercially available fluorophores can be used as antennas to capture long-wavelength light to promote scission of the CoC bond at wavelengths up to 800 nm. The ability to control the ...
Wang Yanping - - 2013
Multiple sclerosis (MS) is a chronic debilitating disease, with lowest incidence in equatorial regions and highest incidence in temperate regions. This relationship is believed to be related to sunlight or UV light exposure. Recent evidence with experimental autoimmune encephalomyelitis (EAE), an animal model of MS, established that this suppression is ...
Zhong Ming - - 2012
Light is both the ultimate energy source for most organisms and a rich information source. Vitamin A-based chromophore was initially used in harvesting light energy, but has become the most widely used light sensor throughout evolution from unicellular to multicellular organisms. Vitamin A-based photoreceptor proteins are called opsins and have ...
Guneser O - - 2012
The objective of this study was to investigate and compare the effects of UV light and heat treatment on vitamins A, B(2), C, and E in cow and goat milk. Vitamins were analyzed by reverse-phase high-pressure liquid chromatography. Ultraviolet and pasteurization treatments caused loss in vitamin C in milk. Pasteurization ...
Michelson Jennifer - - 2012
To assess light scattering and light transmittance in intraocular lenses (IOLs) explanted because of optic opacification. John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA. Experimental study. Poly(methyl methacrylate) (PMMA) IOLs with snowflake degeneration, hydrophilic acrylic IOLs with different calcification patterns, and 1 calcified silicone IOL ...
Simunovic Matthew P - - 2012
The normal human crystalline lens absorbs UV and short-wavelength visible electromagnetic radiation. Early intraocular lenses (IOLs) permitted the transmission of such radiation to the retina following cataract extraction. Experimental studies of the absorption profile of the crystalline lens and animal studies demonstrating the deleterious effects of short-wavelength radiation on the ...
Hayashi Ken - - 2012
PURPOSE: To investigate the long-term effect of surface light scattering and glistenings of various intraocular lenses (IOLs) on visual function and optical aberrations after cataract surgery. DESIGN: Case-control study. METHODS: Thirty-five eyes that underwent implantation of a hydrophobic acrylic, silicone, or polymethyl methacrylate (PMMA) IOL more than 10 years ago ...
Schmack Ingo - - 2012
To evaluate potential differences in the quality of vision after implantation of a blue light-filtering intraocular lens (IOL) and an ultraviolet (UV) light-filtering IOL. Department of Ophthalmology, Ruhr-University, Bochum, Germany. Prospective randomized cohort study. Patients with age-related cataract had bilateral standardized small-incision Kelman phacoemulsification-based cataract surgery with implantation of a ...
Gray Rob - - 2012
To evaluate whether the previously established benefit of blue light-filtering intraocular lenses (IOLs) when driving in glare conditions is maintained in patients previously implanted with a blue light-filtering toric IOL. Department of Applied Psychology, Arizona State University, Mesa, Arizona, USA. Comparative case series. The study comprised patients with a blue ...
Felipe Adelina - - 2012
PURPOSE:To evaluate the changes in optical quality when toric intraocular lenses (IOL) are rotated or tilted and to demonstrate that IOL rotation produces an increasing effect of aberrations. METHODS:Modulation transfer function (MTF) and average modulation were used to analyze the image quality of a toric IOL. The axis of the ...
Miyata Kazunori - - 2012
To assess the long-term increase in surface light scattering of foldable hydrophobic acrylic intraocular lenses (IOLs) and to evaluate its effect on visual acuity. Miyata Eye Hospital, Miyazaki, Japan. Cross-sectional study. The clinical records of patients who received an Acrysof IOL (study group) or a Sensar AR40 or AR40e IOL ...
Zhu Xiao-feng - - 2012
A number of published randomized controlled trials have been conducted to evaluate visual performance of blue light-filtering intraocular lenses (IOL) and UV light-filtering intraocular lenses (IOL) after cataract phacoemulsification surgery. However, results have not always been consistent. Therefore, we carried out a meta-analysis to compare the effectiveness of blue light-filtering ...
Li Jingrong - - 2011
This study had three main goals: to assess the degree of suppression in patients with strabismic, anisometropic, and mixed amblyopia; to establish the relationship between suppression and the degree of amblyopia; and to compare the degree of suppression across the clinical subgroups within the sample. Using both standard measures of ...
Qian Jin - - 2011
Regioregular poly(3-hexylthiophene) (P3HT) was employed as a hole transport material and assistant light absorber for the fabrication of a CdS quantum dot-sensitized solid-state solar cell, by which a power-conversion efficiency of 1.42% was achieved under an AM1.5 G (100 mW cm(-2)) condition.
Liu Y - - 2011
We developed a sol-gel method using photo-induced desorption for size-controlled ZnO quantum dots (QDs). This method successfully controlled the size and size variance of ZnO QDs, and size fluctuations decreased from 23% to 18% depending on the illuminated light intensity. The sol-gel synthesis effectively reduced the number of defect levels ...
Wuerger Sophie M - - 2011
Global motion integration mechanisms can utilize signals defined by purely chromatic information. Is global motion integration sensitive to the polarity of such color signals? To answer this question, we employed isoluminant random dot kinematograms (RDKs) that contain a single chromatic contrast polarity or two different polarities. Single-polarity RDKs consisted of ...
Watamaniuk Scott N J - - 2011
Global flow occurs when random dots, each selecting their direction of motion randomly each frame from a distribution of directions spanning up to 180 deg, appear to move as a whole in the mean direction of the components. This percept arises because the visual system integrates the many independent local ...
Oh Jeong Rok - - 2011
A variety of efficient green, yellow, and amber monochromatic phosphor-converted light-emitting diodes (pc-LEDs) were fabricated by simply capping a long-wave pass filter (LWPF) on top of LED packing associated with each corresponding powder phosphor. In this paper, the luminous efficacy and color purity of two green, three yellow, and two ...
Shan Yuping - - 2011
We applied force spectroscopy based on atomic force microscope (AFM) to demonstrate the possibility of measuring the interaction force between single quantum-dots (QDs) and living cells at single particle level under native conditions. In the force-distance cycle, we recorded the events of cellular uptake of single QDs and single QD ...
Hu Lian - - 2011
For optoelectronic applications, colloidal CdSe quantum dots (QDs) have been integrated into solid devices by using optically transparent polymer matrices that embedded the colloidal QDs. We systematically studied the effect of annealing and photoactivation on the band-band (BB) and surface trap state (STS) transitions of colloidal CdSe QDs embedded in ...
Liu Yu - - 2011
Nano-sphere lithography technique was used to fabricate nano-patterned Si substrates with various depths by controlling the etching time. The depth-dependent broadband anti-reflection was observed and the reflectivity could be reduced to 5%. By depositing Si quantum dots/SiO<sub>2</sub> multilayer on nano-patterned substrate, the reflection was further suppressed and luminescence intensity was ...
Wang Fu - - 2011
We demonstrate the first white light-emitting device originating from single carbon dot components. A maximum external quantum efficiency of 0.083% at a current density of 5 mA cm(-2) with a color-rendering index of 82 is realized, indicating that carbon dots have great potential to be an alternative phosphor for fabricating ...
Cottereau Benoit R - - 2011
We used source imaging of visual evoked potentials to measure neural population responses over a wide range of horizontal disparities (0.5-64 arcmin). The stimulus was a central disk that moved back and forth across the fixation plane at 2 Hz, surrounded either by binocularly uncorrelated dots (disparity noise) or by ...
Põder Endel - - 2011
Dot lattices are very simple multi-stable images where the dots can be perceived as being grouped in different ways. The probabilities of grouping along different orientations as dependent on inter-dot distances along these orientations can be predicted by a simple quantitative model. L. Bleumers, P. De Graef, K. Verfaillie, and ...
Li Hsin-Hung - - 2011
We demonstrate a novel surround modulation of global form perception by using Glass patterns in a center-surround configuration. Glass patterns contain randomly distributed dot pairs, or dipoles, whose orientations are determined by a geometric transform. By integrating across dipoles, an observer can perceive a global structure in the image. We ...
Iyer Padma B - - 2011
The visual system can detect coherent motion in the midst of motion noise. This is accomplished with motion-sensitive channels, each of which is tuned to a limited range of motion directions. Our aim was to show how a single channel is affected by motions both within and outside its tuning ...
Hirai Masahiro - - 2011
Directional information can be retrieved from a point-light walker (PLW) in two different ways: either from recovering the global shape of the articulated body or from signals in the local motion of individual dots. Here, we introduce a voluntary eye movement task to assess how the direction of a centrally ...
Corbett Jennifer E - - 2011
We tested whether the intervening time between multiple glances influences the independence of the resulting visual percepts. Observers estimated how many dots were present in brief displays that repeated one, two, three, four, or a random number of trials later. Estimates made farther apart in time were more independent, and ...
Zhang Yu - - 2010
We report in this communication the design and fabrication of solution-processed white light-emitting diodes (LEDs) containing a bilayer of heavy metal-free colloidal quantum dots (QDs) and polymer in the device active region. White electroluminescence was obtained in the LEDs by mixing the red emission of ZnCuInS/ZnS core/shell QDs and the ...
Noguchi Yasuki - - 2011
To analyze complex scenes efficiently, the human visual system performs perceptual groupings based on various features (e.g., color and motion) of the visual elements in a scene. Although previous studies demonstrated that such groupings can be based on a single feature (e.g., either color or motion information), here we show ...
Norell Bader Amanda J - - 2010
We report color-tunable light-emitting devices employing CdSe/ZnS quantum dots (QDs) blended into a polymer light-emitting electrochemical cell (LEC) architecture. This novel structure circumvents the charge-tunneling barrier of QDs to achieve bright, uniform, and highly voltage-independent electroluminescence, with nearly all emission generated by the QDs. By blending varying ratios of two ...
Barlow Horace - - 2011
Neurons that respond selectively to the orientation of visual stimuli were discovered in V1 more than 50 years ago, but it is still not fully understood how or why this is brought about. We report experiments planned to show whether human observers use cross-correlation or auto-correlation to detect oriented streaks ...
Cassanello Carlos R - - 2011
Edwards and Badcock (Vision Research 35, 2589, 1995) argued for independent first-order (FO) and second-order (SO) motion systems up to and including the global-motion level. That study used luminance (which they called FO) and contrast (SO) modulated dots. They found that SO noise dots did not mask signal extraction with ...
Brooks Kevin R - - 2010
It has been established that the motion in depth of stimuli visible to both eyes may be signalled binocularly either by a change of disparity over time or by the difference in the velocity of the images projected on each retina, known as an interocular velocity difference. A two-interval forced-choice ...
Greene Michelle R - - 2010
Adaptation is ubiquitous in the human visual system, allowing recalibration to the statistical regularities of its input. Previous work has shown that global scene properties such as openness and mean depth are informative dimensions of natural scene variation useful for human and machine scene categorization (Greene & Oliva, 2009b; Oliva ...
Lee Ya-Ju - - 2010
A hybrid structure of CdSe quantum dots (QDs) (λ = 640 nm) spin-coated on the indium gallium nitride (InGaN) nanorod light-emitting diode (LED, λ = 525 nm) is successfully fabricated. Experimental results indicate that the randomness and the minuteness of nanorods scatter the upcoming green light into the surrounding CdSe ...
Bestelmeyer Patricia E G - - 2010
Previous research has demonstrated perceptual aftereffects for emotionally expressive faces, but the extent to which they can also be obtained in a different modality is unknown. In two experiments we show for the first time that adaptation to affective, non-linguistic vocalisations elicits significant auditory aftereffects. Adaptation to angry vocalisations caused ...
Eramudugolla Ranmalee - - 2011
A period of exposure to trains of simultaneous but spatially offset auditory and visual stimuli can induce a temporary shift in the perception of sound location. This phenomenon, known as the 'ventriloquist aftereffect', reflects a realignment of auditory and visual spatial representations such that they approach perceptual alignment despite their ...
Liu Taosheng - - 2011
Attending to a feature in one location can produce feature-specific modulation in a different location. This global feature-based attention effect has been demonstrated using two stimulus locations. Although the spread of feature-based attention is presumed to be constant across spatial locations, it has not been tested empirically. We examined the ...
Dils Alexia Toskos - - 2010
Do people spontaneously form visual mental images when understanding language, and if so, how truly visual are these representations? We test whether processing linguistic descriptions of motion produces sufficiently vivid mental images to cause direction-selective motion adaptation in the visual system (i.e., cause a motion aftereffect illusion). We tested for ...
Hills Peter J - - 2010
We tested the magnitude of the face identity aftereffect following adaptation to different modes of adaptors in four experiments. The perceptual midpoint between two morphed famous faces was measured pre- and post-adaptation. Significant aftereffects were observed for visual (faces) and nonvisual adaptors (voices and names) but not nonspecific semantic information ...
Diegmann Julia - - 2010
Circadian clocks continue to oscillate in constant conditions with their own period (tau) and entrain to a cyclic environment by adjusting their intrinsic period to that of the zeitgeber. When circadian clocks are released from entrained to constant conditions, the tau of their initial free-run often depends on the nature ...
Fukiage Taiki - - 2010
The flash-lag effect refers to the phenomenon where a flash of a stationary stimulus presented adjacent to a moving stimulus appears to lag behind it. We investigated whether the flash-lag effect affected the tilt aftereffect using two sets of vertical gratings for a flash and a moving stimulus that created ...
Green D A DA Centre for Human and Aerospace Physiological Sciences, Division of Applied Biomedical Research, Department of Physiology, King's College London, Guys Campus, London, SE1 1UL, - - 2010
Walking onto a stationary sled previously experienced as moving induces locomotor aftereffects (LAE, or "broken escalator phenomenon"). This particular form of aftereffect can develop after a single adaptation trial and occurs despite subjects being fully aware that the sled will not move. Here, we investigate whether such strong LAE expression ...
Oruç Ipek - - 2010
Previously, repulsive perceptual-shift face aftereffects have been reported. Here, we introduce a novel face adaptation method involving changes in contrast thresholds for face recognition. We find non-monotonic changes for adapted faces, with facilitation at short and suppression at long durations. Thresholds for unadapted faces were unaffected at short but elevated ...
Jackson Stuart - - 2010
Recent computational models of biological motion perception operate on ambiguous two-dimensional representations of the body (e.g., snapshots, posture templates) and contain no explicit means for disambiguating the three-dimensional orientation of a perceived human figure. Are there neural mechanisms in the visual system that represent a moving human figure's orientation in ...
Cziraki Csaba - - 2010
Prolonged exposure to complex stimuli, such as faces, biases perceptual decisions toward nonadapted, dissimilar stimuli, leading to contrastive aftereffects. Here we tested the neural correlates of this perceptual bias using a functional magnetic resonance imaging adaptation (fMRIa) paradigm. Adaptation to a face or hand stimulus led to aftereffects by biasing ...
Ghuman Avniel Singh - - 2010
Prolonged viewing of a stimulus results in a subsequent perceptual bias. This perceptual adaptation and the resulting aftereffect reveal important characteristics regarding how perceptual systems are tuned. These aftereffects occur not only for simple stimulus features but also for high-level stimulus properties. Here we report a novel cross-category adaptation aftereffect ...
Planetta Peggy J PJ Department of Psychology, Wilfrid Laurier University, 75 University Avenue, West Waterloo, ON N2L 3C5, - - 2010
The motion aftereffect (MAE) refers to the apparent motion of a stationary stimulus following adaptation to a continuously moving stimulus. There is a growing consensus that the fast adapting (FA) rather than the slowly adapting (SA) afferent units mediate the tactile version of the MAE. The present study investigated which ...
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