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Wessels Johannes T - - 2012
Proper illumination is essential for light microscopy. Whereas in early years incandescent light was the only illumination, today, more and more specialized light sources, such as lasers or arc lamps are used. Because of the high efficiency and brightness that light-emitting diodes (LED) have reached today, they have become a ...
Park Hoo Keun - - 2011
This paper reports the optical effects of a two-dimensional (2D) SiN<sub>x</sub> photonic crystal layer (PCL) on Y<sub>3</sub>Al<sub>5</sub>O<sub>12</sub>:Ce<sup>3+</sup> (YAG:Ce) yellow ceramic plate phosphor (CPP) in order to enhance the forward emission of YAG:Ce CPP-capped high-power white light-emitting diodes (LEDs). By adding the 2D SiN<sub>x</sub> PCL with a 580 nm lattice constant, ...
Pyschny Verena - - 2011
PURPOSE: The objective of the study was to investigate the influence of bimodal stimulation upon hearing ability for speech recognition in the presence of a single competing talker. METHOD: Speech recognition was measured in three listening conditions: hearing aid alone (HA); cochlear implant alone (CI) and both devices together (CI ...
Mulsow Jason - - 2011
Although electrophysiological methods of measuring the hearing sensitivity of pinnipeds are not yet as refined as those for dolphins and porpoises, they appear to be a promising supplement to traditional psychophysical procedures. In order to further standardize electrophysiological methods with pinnipeds, a within-subject comparison of psychophysical and auditory steady-state response ...
Gillam Barbara J - - 2011
Figure-ground perception is typically described as seeing one surface occluding another. Figure properties, not ground properties, are considered the significant factors. In scenes, however, a near surface will often occlude multiple contours and surfaces, often at different depths, producing alignments that are improbable except under conditions of occlusion. We thus ...
Iwasa Masatomo - - 2011
A particular dynamic steady state emerging in the swarm oscillator model-a system of interacting motile elements with an internal degree of freedom-is presented. In the state, elements form a rotating triangle whose corners appear to catch and throw elements. This motion is referred to as "juggling motion" in this paper. ...
Luqué L D - - 2011
The objective of this study was to determine the effect of feeding zilpaterol hydrochloride (ZH) on the shelf life and stability of ground beef. Beef knuckles and plates were obtained from USDA Select beef heifer carcasses from control (CON) animals or those supplemented with ZH (8.33 mg/kg of dietary DM ...
Weingart Oliver - - 2011
The photochemical cis-trans isomerization of retinal in rhodopsin is investigated by structure sampling and excited state QM/MM trajectories with surface hopping. The calculations uncover the motions responsible for photoproduct formation and elucidate the reasons behind the efficient photoisomerization in the primary event of visual transduction.
Teki Sundeep - - 2011
Auditory figure-ground segregation, listeners' ability to selectively hear out a sound of interest from a background of competing sounds, is a fundamental aspect of scene analysis. In contrast to the disordered acoustic environment we experience during everyday listening, most studies of auditory segregation have used relatively simple, temporally regular signals. ...
Cooper Emily A - - 2011
Depth estimates from disparity are most precise when the visual input stimulates corresponding retinal points or points close to them. Corresponding points have uncrossed disparities in the upper visual field and crossed disparities in the lower visual field. Due to these disparities, the vertical part of the horopter-the positions in ...
Feitosa-Santana Claudia - - 2011
Is a retinal representation of an edge necessary to constrain the reach of color filling-in? If so, then color filling-in should not be constrained by illusory contours, because they do not exist at a retinal level. Alternatively, if color filling-in is constrained by contours at a perceptual level of neural ...
Martinez-Molina Noelia - - 2011
Neuroblasts generated in the adult subventricular zone (SVZ) migrate through the rostral migratory stream (RMS) to the olfactory bulb (OB). Previous work uncovered motility ranging from straight to complex, but it was unclear if directional changes were stochastic or exhibited stereotypical patterns. Here, we provide the first in-depth two-photon time-lapse ...
Cooper William E WE - - 2010
Escape by Anolis lizards is influenced by microhabitats and fight initiation distance increases with predation risk. Differences in microhabitat use among ecomorphs affect escape behavior, but only two studies have reported ecomorphological differences in flight initiation distance among Greater Antillean species. I studied effects of predation risk and microhabitats on ...
Kharlamova Anastasia V - - 2010
Directional asymmetry (DA) is a characteristic of most vertebrates, most strikingly exhibited by the placement of various organs (heart, lungs, liver, etc.) but also noted in small differences in the metrics of skeletal structures such as the pelvis of certain fish or sauropsids. We have analyzed DA in the skeleton ...
Susini Patrick - - 2010
Three experiments on loudness of sounds with linearly increasing levels were performed: global loudness was measured using direct ratings, loudness change was measured using direct and indirect estimations. Results revealed differences between direct and indirect estimations of loudness change, indicating that the underlying perceptual phenomena are not the same. The ...
Phillips John B - - 2010
In terrestrial organisms, sensitivity to the Earth's magnetic field is mediated by at least two different magnetoreception mechanisms, one involving biogenic ferromagnetic crystals (magnetite/maghemite) and the second involving a photo-induced biochemical reaction that forms long-lasting, spin-coordinated, radical pair intermediates. In some vertebrate groups (amphibians and birds), both mechanisms are present; ...
Hoch Matthew C - - 2011
The purpose of this study was to examine the relationships between dorsiflexion range of motion on the weight-bearing lunge test (WBLT) and normalized reach distance in three directions on the Star Excursion Balance Test (SEBT). Thirty-five healthy adults (14 males, 21 females, age: 25.9±6.7 years, height: 166.7±22.9 cm, weight: 76.7±22.8 ...
Ziat Mounia - - 2010
In vision, the discovery of the phenomenon of saccadic suppression of displacement has made important contributions to the understanding of the stable world problem. Here, we report a similar phenomenon in the tactile modality. When scanning a single Braille dot with two fingers of the same hand, participants were asked ...
Elstrott Justin - - 2010
Direction-selective ganglion cells (DSGCs) fire robustly for stimuli moving along one direction of motion and are strongly inhibited by stimuli moving in the opposite, or null, direction. In contrast to direction-selective neurons in primary visual cortex, a role for neural activity in the development of direction-selective retinal circuits has not ...
Jeffery Kathryn J - - 2010
A study shows that spatial learning is accompanied by the reorganization of place fields of hippocampal CA1 neurons, and that this reorganization is subsequently reactivated in an NMDA-dependent manner for memory consolidation.
Fan Zhao - - 2010
In a recent study (Fan, Z., & Harris, J. (2008). Perceived spatial displacement of motion-defined contours in peripheral vision. Vision Research, 48(28), 2793-2804), we demonstrated that virtual contours defined by two regions of dots moving in opposite directions were displaced perceptually in the direction of motion of the dots in ...
Maruyama Masaki - - 2010
Reconstruction of neural current sources from magnetoencephalography (MEG) data provides two independent estimates of the instantaneous current modulus and its direction. Here, we explore how different information on the modulus and direction affects the inter-hemisphere connectivity of the human medial temporal complex (hMT+). Connectivity was quantified by mutual information values ...
Bourrelly A - - 2010
We studied the effect of static pitch body tilts on the perception of self-motion direction induced by a visual stimulus. Subjects were seated in front of a screen on which was projected a 3D cluster of moving dots visually simulating a forward motion of the observer with upward or downward ...
Wilkie R M - - 2010
Looking at the inside edge of the road when steering a bend seems to be a well-established strategy linked to using a feature called the tangent point. An alternative proposal suggests that the gaze patterns observed when steering result from looking at the points in the world through which one ...
Naito Tomoyuki - - 2010
A number of previous studies have extensively investigated directional anisotropy in motion perception. However, consensus has not been reached regarding the nature of motion directional anisotropies in human vision. In this study, we investigated the directional anisotropy of human motion perception by moving random-dot stimuli in the peripheral upper visual ...
Enciso Germán A - - 2010
Displaced starburst amacrine cells (SACs) are retinal interneurons that exhibit GABA( A ) receptor-mediated and Cl (-) cotransporter-mediated, directionally selective (DS) light responses in the rabbit retina. They depolarize to stimuli that move centrifugally through the receptive field surround and hyperpolarize to stimuli that move centripetally through the surround (Gavrikov ...
Tanner David A - - 2010
The waggle dance of the honey bee is used to recruit nest mates to a resource, though direction indicated for a resource may vary greatly within a single dance. Some authors suggest that this variation exits as an adaptation to distribute recruits across a patch of flowers, and that, due ...
Wang Fu - - 2010
A facile chemical method has been developed to synthesise highly efficient functionalized carbon dots; when illuminated with 407 nm light, both the solution and film emitted white-light directly.
Ruzzoli Manuela - - 2010
Transcranial magnetic stimulation (TMS) is a technique used to study perceptual, motor, and cognitive functions in the human brain. Its effects have been likened to a "virtual brain lesion," but a direct test of this assumption is lacking. To verify this hypothesis, we measured psychophysically the interaction between the neural ...
Chen Yaohui - - 2010
We show that ultrafast carrier dynamics plays an important role on slow- and fast-light effects based on coherent population oscillations in quantum-dot semiconductor waveguides. Fast light in the gain regime and slow light in the absorption regime are found to be enhanced at frequencies beyond the usual limits of the ...
Lee Yunjo - - 2010
Discriminating the identity of static face views is viewpoint-dependent (Lee, Matsumiya, & Wilson, 2006), yet the benefit of facial motion on improving cross-view discrimination remains unclear. We investigate here, whether seeing a face rotating in a single direction reduces the viewpoint dependence of neighboring views, in particular, along the trajectory ...
Tata Matthew S - - 2010
Attended stimuli typically evoke larger event-related potentials (ERPs) than unattended stimuli. We previously reported an exception when an optic-flow pattern is interleaved with stationary dots. Reversals of motion direction evoked a larger N200 peak when attention was directed to the stationary dots. We replicated and further characterized this result: the ...
Dakin Steven C - - 2010
Although visual systems are optimized to deal with the natural visual environment, our understanding of human motion perception is in large part based on the use of artificial stimuli. Here, we assessed observers' ability to estimate the direction of translating natural images and fractals by having them adjust the orientation ...
Gheorghiu Elena - - 2010
We have investigated the global and local motion tuning properties of curvature coding mechanisms using two shape after-effects believed to be mediated by curvature-sensitive mechanisms: the shape-frequency after-effect, or SFAE, and the shape-amplitude after-effect, or SAAE. The SFAE and SAAE are the phenomena in which adaptation to a sine-wave-shaped contour ...
Wood Vanessa - - 2010
We report a novel unipolar light-emitting device architecture that operates using direct-current, field-driven electroluminescence of colloidally synthesized quantum dots (QDs). This device architecture, which is based only on transparent ceramics and QDs, enables emission from different color QDs and, for the first time, constant QD electroluminescence during extended operation in ...
Tanca Maria - - 2010
The purpose of this work is to study how the brain solves perceptual antinomies, induced by the watercolor illusion in the color and in the figure-ground segregation domain, when they are present in different parts of the same object. The watercolor illusion shows two main effects: a long-range coloration and ...
Barth?lemy Fr?deric V - - 2010
Several recent studies have shown that extracting pattern motion direction is a dynamical process where edge motion is first extracted and pattern-related information is encoded with a small time lag by MT neurons. A similar dynamics was found for human reflexive or voluntary tracking. Here, we bring an essential, but ...
de Oliveira Rita Ferraz - - 2009
Reports an error in "Experts appear to use angle of elevation information in basketball shooting" by Rita Ferraz de Oliveira, Raôul R. D. Oudejans and Peter J. Beek (Journal of Experimental Psychology: Human Perception and Performance, 2009[Jun], Vol 35[3], 750-761). On page 754 of the article, Figure 3 was repeated ...
Baker Daniel H - - 2010
How does nearby motion affect the perceived speed of a target region? When a central drifting Gabor patch is surrounded by translating noise, its speed can be misperceived over a fourfold range. Typically, when a surround moves in the same direction, perceived centre speed is reduced; for opposite-direction surrounds it ...
Gurnsey Rick - - 2010
There is evidence that human observers are more sensitive to the direction-of-heading of point-light walkers defined by first-order than second-order motions. We addressed this question by measuring the minimum direction difference (azimuth) that observers could discriminate when the dots composing the walkers were conveyed by first or second-order motions. Sensitivity ...
Yoshimura N - - 2009
It is necessary for brain-computer interfaces (BCIs) to be non-offensive devices for daily use to improve the quality of life of users, especially for the motor disabled. Some BCIs which are based on steady-state visual evoked potentials (SSVEPs), however, are unpleasant because users have to gaze at high-speed blinking light ...
de Ibarra Natalie Hempel - - 2009
Many bees and wasps learn about the immediate surroundings of their nest during learning flights, in which they look back towards the nest and acquire visual information that guides their subsequent returns. Visual guidance to the nest is simplified by the insects' tendency to adopt similar viewing directions during learning ...
Vanni M P - - 2010
In the visual system, neurons with similar functional properties such as orientation and direction selectivity are clustered together to form modules. Optical imaging recordings in combination with episodic paradigms have been previously used to estimate direction selectivity, a fundamental property of visual neurons. The major drawback of the episodic approach ...
Wiltschko Wolfgang - - 2010
Under 502 nm turquoise light combined with 590 nm yellow light and in total darkness, European robins, Erithacus rubecula, no longer prefer their migratory direction, but exhibit so-called fixed direction responses that do not show the seasonal change between spring and autumn. We tested robins under these light conditions in ...
Neri Peter - - 2009
The response of motion-sensitive neurons to stimuli presented within their receptive field is often affected by stimulation in the surrounding region. These effects have perceptually relevant consequences that can be measured using behavioral techniques. We used psychophysical reverse correlation to characterize directional selectivity in human observers while they processed a ...
Balvin Manuel - - 2009
We performed macroscopic experiments on the motion of a sphere through an array of obstacles that highlight the deterministic nature of the lateral displacements that lead to particle separation in microfluidic systems. The motion of the spheres is irreversible and displays directional locking. The locking directions can be predicted with ...
Gallyamov Marat O - - 2009
Using SFM we have observed a peculiar twisting motion of diblock macromolecules pre-collapsed in ethanol vapour during their subsequent spreading in water vapour. The intrinsic asymmetry of the diblock macromolecules has been considered to be the reason for such twisting. Further, friction-deposited PTFE nano-stripes have been employed as nano-trails with ...
Carrillo-Carri??n Carolina - - 2009
Quantum dots (QDs) are a novel class of inorganic fluorophores, which are gaining widespread recognition as a result of their exceptional photophysical properties. They are rapidly being integrated into existing and emerging technologies, and could play an important role in many areas in the future. Significant phenomena, such as photoactivation, ...
Dépeault Alexandra - - 2009
Recently, we showed that tactile speed estimates are modified by the spatial parameters of moving raised-dot surfaces, specifically dot spacing but not dot disposition (regular, irregular) or density. The purpose of this study was to determine the extent to which tactile roughness perception resembles tactile speed with respect to its ...
Hondzinski Jan M - - 2009
The purposes of this study were to determine whether gaze direction provides a control signal for movement direction for a pointing task requiring a step and to gain insight into why discrepancies previously identified in the literature for endpoint accuracy with gaze directed eccentrically exist. Straight arm pointing movements were ...
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