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Armbruster W Scott - - 2013
Background and AimsSpatial (herkogamy) and temporal (dichogamy) separation of pollen presentation and stigma receptivity have been interpreted as reducing interference between male and female functions in hermaphroditic flowers. However, spatial separation leads to a potential conflict: reduced pollination accuracy, where pollen may be placed in a location on the pollinator ...
Suzuki Takeshi - - 2012
Non-diapausing spider mites (Tetranychus urticae) live on the undersurface of host leaves during summer, but diapausing mites overwinter in dark hibernacula. The light environments of these habitats would differ: visible radiation (VIS) but not ultraviolet radiation (UV) would reach the undersurface, but neither would enter dark hibernacula. Thus, mites of ...
Hadad Bat-Sheva - - 2012
Patients deprived of visual experience during infancy by dense bilateral congenital cataracts later show marked deficits in the perception of global motion (dorsal visual stream) and global form (ventral visual stream). We expected that they would also show marked deficits in sensitivity to biological motion, which is normally processed in ...
Denev Iliya - - 2012
The effect of prolonged light deprivation on ultrastructure, pigment composition and functions of photosynthetic apparatus of the resurrection plant Haberlea rhodopensis Friv. (Gesneriaceae) was studied. For this purpose intact plants were kept in darkness for up to six months. H. rhodopensis demonstrated extraordinary ability to preserve its photosynthetic machinery intact ...
de Margerie E - - 2012
Previous maternal deprivation experiments demonstrated that absence of maternal care impacts the behavioral development of young animals. Here we assessed the influence of the presence of a mothering hen on the spatial exploration of Japanese quail chicks, after the mothering period. Brooded and nonbrooded chicks were placed in a novel ...
Gardiner Jayne M - - 2012
Animals use a suite of sensory modalities to precisely locate and capture prey. While numerous studies have examined the effects of sensory deprivation on the behaviors leading to prey capture and while it is generally believed that information in the pre-strike period determines the way fish capture prey, this study ...
Huang Shih-Miao - - 2011
This study explored the degree of rating consistency for different icon-background color combinations, and identified the color combinations with the highest rating for consistency. Rating consistency is the degree of agreement among subjective aesthetic preferences for a specific color combination. In total, 3306 color combinations were rated in this study. ...
Shultz R - - 2011
The trajectories of skin-mounted markers tracked with optical motion capture are assumed to be an adequate representation of the underlying bone motions. However, it is well known that soft tissue artifact (STA) exists between marker and bone. This study quantifies the STA associated with the hindfoot and midfoot marker clusters ...
Master Suely - - 2012
Spectrographic analysis of male actors' voices showed a cluster, the "actor's formant" (AF), which is related to the perception of good and projected voice quality. To date, similar phenomena have not been described in the voices of actresses. Therefore, the objective of the current investigation was to compare actresses' and ...
Sturm Veit - - 2011
A novel preferential looking (PL) procedure that uses quantitative analysis of visual scanning parameters is presented. Nine adult subjects were presented with a set of 14 visual stimuli (stimuli included three uniform gray fields and one field with black-and-white square wave gratings) spanning the range of spatial frequencies from 1.5 ...
Flevaris Anastasia V AV Department of Psychology, University of California, Berkeley, CA, USA. - - 2011
Ample evidence suggests that global perception may involve low spatial frequency (LSF) processing and that local perception may involve high spatial frequency (HSF) processing (Shulman, Sullivan, Gish, & Sakoda, 1986; Shulman & Wilson, 1987; Robertson, 1996). It is debated whether SF selection is a low-level mechanism associating global and local ...
Lancioni Giulio - - 2011
Objective: To evaluate microswitch-cluster technology to help a post-coma man with multiple disabilities increase adaptive responding and reduce head forward tilting. Method: The intervention programme initially focused on promoting a simple adaptive response (i.e. manipulating and moving a wobbling, ball-like device), which produced brief periods of preferred stimulation. Subsequently, this ...
Howard Christina J - - 2010
Under some circumstances, moving objects capture attention. Whether a change in the direction of a moving object attracts attention is still unexplored. We investigated this using a continuous tracking task. In Experiment 1, four grating patches changed smoothly and semirandomly in their positions and orientations, and observers attempted to track ...
Rüter Johannes - - 2010
How the brain integrates visual information across time into coherent percepts is an open question. Here, we presented two verniers with opposite offset directions one after the other. A vernier consists of two vertical bars that are horizontally offset. When the two verniers are separated by a blank screen (interstimulus ...
Kee Jack Sheng - - 2010
We have designed, fabricated and characterized poly(dimethylsiloxane) (PDMS) arrayed waveguide grating (AWG) with four-channel output for operation in the visible light wavelength range. The PDMS AWG was realized based on the single-mode PDMS rib waveguide. The device was designed for 1 nm channel spacing with the wavelength ranging from 639 ...
Lee Barry B - - 2011
Segregation of chromatic and luminance signals in afferent pathways are investigated with a grating stimulus containing luminance and chromatic components of different spatial frequencies. Ganglion cell recordings were obtained from the retinae of macaques (Macaca fascicularis). Cell responses to the 'compound' gratings were compared to responses to standard chromatic and ...
Bai Benfeng - - 2010
We propose and investigate the use of slanted surface-relief gratings with nonbinary profiles as high-efficiency broadband couplers for light guides. First, a Chandezon-method-based rigorous numerical formulation is presented for modeling the slanted gratings with overhanging profiles. Then, two typical types of slanted grating couplers--a sinusoidal one and a trapezoidal one--are ...
Gheorghiu Elena - - 2010
The shape-frequency and shape-amplitude after-effects, or SFAE and SAAE, are shifts in the perceived shape-frequency and perceived shape-amplitude of a sinusoidal test contour following adaptation to a similar-shaped contour. These shape-effects are the shape analogs of the well-known size after-effect discovered by Blakemore and Sutton (1969), so it is possible ...
Su Yong R YR Department of Basic Sciences, Pennsylvania College of Optometry at Salus University, Elkins Park, PA 19027, - - 2010
A monocular boundary contour (MBC) rivalry stimulus has two half-images, a homogeneous grating and the same homogeneous grating with an additional disc region. The outline/frame of the MBC disc is created by relative phase-shift, or orientation-difference. We found the increment contrast threshold and reaction time to detect a monocular Gabor ...
Seno Takeharu - - 2010
We conducted a series of psychophysical experiments to investigate the effects of static visual components on visually-induced self-motion perception ('vection'). Static gratings with various spatial frequencies were added to a moving vertical grating, presented either orthogonally or parallel to the motion of the grating. Adding a static component orthogonal to ...
Sato Akira - - 2010
By designing and fabricating appropriate structures, guided-mode resonant gratings can be used as optical filters to attain extremely narrow bandwidths. This high performance makes it difficult to couple light into a waveguide via the grating, which demands extremely high mechanical accuracy to adjust the incident conditions. This paper shows both ...
Liedtke Alicia - - 2010
We report a new single-step method to directly imprint nanometer-scale structures on photoreactive organic semiconductors. A surface relief grating is spontaneously formed when a light-emitting, liquid crystalline, and semiconducting thin film is irradiated by patterned light generated using a phase mask. Grating formation requires no postannealing nor wet etching so ...
Sanchez-Brea Luis Miguel - - 2010
We present a collimation technique based on a double grating system to locate with high accuracy an emitter in the focal plane of a lens. Talbot self-images are projected onto the second grating producing moiré interferences. By means of two photodetectors positioned just behind the second grating, it is possible ...
Rom?n-Hern?ndez Edwin - - 2010
In this work we use the geometrical point of view of the Ronchi test and the caustic-touching theorem to describe the structure of the ronchigrams for a parabolical mirror when the point light source is on and off the optical axis and the grating is placed at the caustic associated ...
Jemel Boutheina - - 2010
Despite the vast amount of behavioral data showing a pronounced tendency in individuals with autism spectrum disorder (ASD) to process fine visual details, much less is known about the neurophysiological characteristics of spatial vision in ASD. Here, we address this issue by assessing the contrast sensitivity response properties of the ...
Niebergall Robert - - 2010
Visual-spatial attention enhances the perception of behaviorally relevant stimuli. One issue that remains unclear is whether attention is preferentially allocated to stimuli that remain fixed in one reference frame (e.g., retina-centered), or whether it could be equally allocated to stimuli fixed in other frames. We investigated this issue by asking ...
Poljak Zvonimir - - 2010
The systemic form of porcine circovirus associated disease (PCVAD), also known as postweaning multisystemic wasting syndrome (PMWS) was initially detected in the early 1990s. Starting in 2004, the Canadian swine industry experienced considerable losses due to PCVAD, concurrent with a shift in genotype of porcine circovirus type 2 (PCV2). Objectives ...
Evans David W DW School of Optometry, Indiana University, Bloomington, IN 47405, United - - 2010
The effect of sampling irregularity and window size on orientation discrimination was investigated using discretely sampled gratings as stimuli. For regular sampling arrays, visual performance could be accounted for by a theoretical analysis of aliasing produced by undersampling. For irregular arrays produced by adding noise to the location of individual ...
Zhao Dongyu - - 2010
In this communication, we describe a simple process for the generation of surface relief gratings (SRG). SRG are fabricated from a photocross-linkable organic monomer PDACE (4-propyldiphenylacetylenecarboxylic acid cinnamyl ester) with cinnamyl ester and tolane groups, by using a patterned non-polarized UV light irradiation. The patterns of the surface relief structures ...
Bourgin Y - - 2009
A monolithic double-grating phase mask comprising three short-pitch grating sections of spatial frequencies k(1) and k(2) collocated at one side of a substrate produces a large-period interferogram without higher harmonics to print in a photoresist film a latent grating of small spatial frequency equal to twice k(2)-k(1). When incorporated in ...
Wang Albert A School of Electrical and Computer Engineering, Cornell University, Ithaca, New York 14853, - - 2009
We present a pixel-scale sensor that uses the Talbot effect to detect the local intensity and incident angle of light. The sensor comprises two local diffraction gratings stacked above a photodiode. When illuminated by a plane wave, the upper grating generates a self-image at the half Talbot depth. The second ...
Sanchez-Brea Luis Miguel - - 2009
We analyze the Talbot effect produced by a mask composed of two diffraction gratings. Combinations with phase and amplitude gratings have been studied in the near-field regime. For a two-phase-gratings configuration, the Talbot effect is canceled, even when using monochromatic light; that is, the intensity distribution is nearly independent of ...
Riahi Mohammadreza - - 2009
We propose the application of a thermally tunable grating as a spatial light modulator. The grooves of a square-well grating are filled with a liquid whose refractive index depends on temperature. The variation of optical characteristics of such a grating with respect to temperature is investigated theoretically and also by ...
Stoykova Elena - - 2009
Phase-shifting profilometry requires projection of sinusoidal fringes on a 3D object. We analyze the visibility and frequency content of fringes created by a sinusoidal phase grating at coherent illumination. We derive an expression for the intensity of fringes in the Fresnel zone and measure their visibility and frequency content for ...
Yoon Jong H - - 2009
Visual perception of a stimulus is a function of the visual context in which it is displayed. Surround suppression is a specific form of contextual modulation whereby the perceived contrast of a center stimulus is decreased by a high-contrast surround. Recent studies have demonstrated that individuals with schizophrenia are less ...
Lochbihler Hans - - 2009
Gratings with periods smaller than visible wavelengths in ambient white light will exhibit enhanced colors if the profile is designed so that resonant light interaction occurs in the visible range. Resonances have a frequency-selective influence to the grating diffraction inducing colors in transmittance and reflectance, respectively. Apart from the well-known ...
Watson Tonya T School of Optometry, University of California, Berkeley, California 94720-2020, USA. - - 2009
Cortical visual impairment (CVI) is a leading cause of bilateral vision impairment. Because many patients with CVI cannot perform an optotype test, their acuity is often measured with a grating stimulus using a preferential looking (PL) test or the visual-evoked potential (VEP) recording. The purpose of this study is to ...
Plainis S - - 2009
Many classical experiments have shown that two superimposed gratings are more easily detected than a single grating, in keeping with probability theory. Here we test the rules for the detection of 2-component compound gratings by extending the range of parameters used in previous experiments. Two complementary methods of deriving summation ...
Merkul'ev A V - - 2009
Previous studies have demonstrated that human contrast sensitivity curves have marked extremes [4]. This phenomenon has not yet been investigated. The present report describes studies of plots of frequency-contrast characteristics obtained using gratings with orientations of 0 degrees , 90 degrees , and 135 degrees . The results showed that: ...
Liu Chien-Hung - - 2009
Linear laser encoders have been widely used for precision positioning control of a linear stage. We develop a five-degrees-of-freedom (5-DOF) laser linear encoder to simultaneously measure the position, straightness, pitch, roll, and yaw errors along one moving axis. This study integrates the circular polarized interferometric technique with the three-dimensional diffracted ...
Hammond Billy R - - 2009
PURPOSE: To investigate whether implanting "blue-filtering" yellow intraocular lenses (IOL) could provide a visual benefit in terms of glare disability and photostress recovery. DESIGN: A case-control study. METHODS: Researchers masked to group assignments tested 58 subjects: 17 with yellow IOLs (AcrySof Natural; SN60WF; Alcon Laboratories Inc, Fort Worth, Texas, USA), ...
Popov Evgeny - - 2009
Extremely shallow lamellar metallic gratings are shown to totally absorb incident light inside a wide angular interval. The full absorption still holds at the homogeneization limit when the period tends toward zero. It is shown that a lamellar grating, illuminated in normal incidence and in transerve magnetic polarization with a ...
Jie Zhang - - 2009
A micromechanical optical modulator called a grating light modulator (GLM) with electrostatic actuation, fabricated by the conventional process, is described. The GLM is operated by the interaction of a stationary reflector and a movable sliding grating. The GLM is a micromechanical phase grating. The phase difference is determined by the ...
Fujimoto Kiyoshi - - 2009
When a walking person is presented in a movie, the background image appears to move in a direction opposite to that of the person's locomotion. This study aimed to quantify the strength of this backscroll illusion and to examine interobserver and intraobserver variability. Stimuli were movie clips that presented a ...
Goutcher Ross - - 2009
Two luminance gratings of identical orientation and opposite directions of motion are seen as moving across one another (i.e. moving transparently) only if they differ in spatial frequency (SF) by a factor of four or more. Identical SF gratings produce counter-phase flicker. This suggests that opposite motions cancel each other ...
Madanipour Khosro - - 2009
We show theoretically and verify experimentally that the modulation transfer function (MTF) of a printing system can be determined by measuring the autocorrelation of a printed Ronchi grating. In practice, two similar Ronchi gratings are printed on two transparencies and the transparencies are superimposed with parallel grating lines. Then, the ...
Stuit Sjoerd M - - 2009
During binocular rivalry (BR), conflicting monocular images are alternately suppressed from awareness. During suppression of an image, contrast sensitivity for probes is reduced by approximately 0.3-0.5 log units relative to when the image is in perceptual dominance. Previous studies on rivalry suppression have led to controversies concerning the nature and ...
Harmening Wolf M - - 2009
The eyes of barn owls (Tyto alba pratincola) display very little aberrations, and have thus excellent optical quality. In a series of behavioral experiments, we tested whether this presumably beneficial feature is also reflected at a perceptual level in this species. As fundamental indicators for visual performance, the spatial contrast ...
Sheliga B M - - 2009
We recorded the initial torsional Ocular Following Responses (tOFRs) elicited at short latency by visual images that occupied the frontal plane and rotated about the lines of sight. Using 1-D radial gratings, the local spatio-temporal characteristics of these tOFRs closely resembled those we previously reported for the hOFRs to horizontal ...
Freeman Elliot - - 2009
Contrast discrimination for an image is usually harder if another image is superimposed on top. We asked whether such contrast masking may be enhanced or relieved depending on cues promoting integration of both images as a single pattern, versus segmentation into two independent components. Contrast discrimination thresholds for a foveal ...
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