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Rychtecký Pavel P Faculty of Science, University of South Bohemia, Branišovská 31, České Budějovice, 37005, Czech Republic, - - 2014
Extracellular phosphatase production by phytoplankton was investigated in the moderately eutrophic Lipno reservoir, Czech Republic during 2009 and 2010. We hypothesized that production of extracellular phosphatases is an additional mechanism of phosphorus acquisition enabling producers to survive rather than to dominate the phytoplankton. Hence, we examined the relationship between light ...
Shoeibi Nasser N Retina Research Center, Mashhad University of Medical Sciences, Mashhad, - - 2014
To introduce a simple and practical method for detecting vitrectomy infusion line position in a hazy media. The position of the infusion cannula was evaluated before and during vitrectomy in 17 eyes of 17 patients with hazy media. This procedure was performed by using the light pipe inserted partially into ...
Cavallo Joel S JS Program in Neuroscience, Department of Psychological and Brain Sciences, Indiana University Bloomington, IN, - - 2014
Extinction of a conditioned association is typically viewed as the establishment of new learning rather than the erasure of the original memory. However, recent research in the nudibranch, Hermissenda crassicornis (H.c.) demonstrated that extinction training (using repeated light-alone presentations) given 15 min, but not 23 h, after memory acquisition reversed ...
Karmakar Chandan - - 2012
The heart rate asymmetry (HRA) is a disproportionate distribution of heart rate signal. The current study was designed to assess the changes in HRA in experimental conditions using Poincaré plot during parasympathetic blockade (atropine infusion) and parasympathetic enhancement (scopolamine administration). After atropine infusion, the heart rate variability in 5 out ...
Boecker Maren - - 2012
In the course of daily living altering environmental conditions or changing internal states often cause us to abandon obsolete planned or initiated actions and force us to update our behavior. The stop-change paradigm, an extension of the very popular stop-signal paradigm, allows the investigation of response inhibition and response re-engagement ...
Ríos-Chelén A A - - 2012
Song learning has evolved within several avian groups. Although its evolutionary advantage is not clear, it has been proposed that song learning may be advantageous in allowing birds to adapt their songs to the local acoustic environment. To test this hypothesis, we analysed patterns of song adjustment to noisy environments ...
Duchateau Nicolas - - 2012
This paper describes a technique to (1) learn the representation of a pathological motion pattern from a given population, and (2) compare individuals to this population. Our hypothesis is that this pattern can be modeled as a deviation from normal motion by means of non-linear embedding techniques. Each subject is ...
White Peter A - - 2012
Forces are experienced in actions on objects. The mechanoreceptor system is stimulated by proximal forces in interactions with objects, and experiences of force occur in a context of information yielded by other sensory modalities, principally vision. These experiences are registered and stored as episodic traces in the brain. These stored ...
Stamatakis A - - 2012
Due to advances in molecular sequencing and the increasingly rapid collection of molecular data, the field of phyloinformatics is transforming into a computational science. Therefore, new tools are required that can be deployed in supercomputing environments and that scale to hundreds or thousands of cores. We describe RAxML-Light, a tool ...
Ahmed Omar J - - 2012
Successful spatial navigation is thought to employ a combination of at least two strategies: the following of landmark cues and path integration. Path integration requires that the brain use the speed and direction of movement in a meaningful way to continuously compute the position of the animal. Indeed, the running ...
Sabin Andrew T - - 2012
Natural sounds are characterized by complex patterns of sound intensity distributed across both frequency (spectral modulation) and time (temporal modulation). Perception of these patterns has been proposed to depend on a bank of modulation filters, each tuned to a unique combination of a spectral and a temporal modulation frequency. There ...
Eisenstein Edward M - - 2012
This paper explores further the "behavioral homeostasis theory" (BHT) regarding the evolutionary significance for organism survival of the two simple non-associative rapidly learned behaviors of habituation and sensitization. The BHT postulates that the evolutionary function of habituation and sensitization throughout phylogeny is to rapidly maximize an organism's overall readiness to ...
Weise Annekathrin - - 2012
Auditory transients (such as sound onset or a frequency transition within a continuous sound) are assumed to parse the auditory input into smaller units enabling the formation of unitary sound representations separately for each segment. This was discovered by using the mismatch negativity (MMN) component of the event-related potential (ERP) ...
Franklin Sae S Computational and Biological Learning Laboratory, Department of Engineering, University of Cambridge, United - - 2012
At an early stage of learning novel dynamics, changes in muscle activity are mainly due to corrective feedback responses. These feedback contributions to the overall motor command are gradually reduced as feedforward control is learned. The temporary increased use of feedback could arise simply from the large errors in early ...
Hoeschele Marisa - - 2012
The fee-bee song of the black-capped chickadee (Poecile atricapillus) is a two-note, tonal song that can be sung at different absolute pitches within an individual. However, these two notes are produced at a consistent relative pitch. Moreover, dominant birds more reliably produce songs with this species-typical interval, compared to subordinate ...
Hirata Yutaka - - 2012
A cerebellum-machine interface (CMI) was developed to test direct causality between single-unit cerebellar Purkinje cell activities and motor learning. The CMI converts Purkinje cell simple spike firing rates into a pulse width modulation signal that drives a single-joint robot arm. The CMI has no adaptive capability, thus any changes observed ...
Ungureanu Mariana - - 2012
Sketch of the configuration of a light-controlled resistive switching memory. Light enters through the Al(2) O(3) uncovered surface and reaches the optically active p-Si substrate, where carriers are photogenerated and subsequently injected in the Al(2) O(3) layer when a suitable voltage pulse is applied. The resistance of the Al(2) O(3) ...
Hoare Derek J - - 2012
That auditory perceptual training may alleviate tinnitus draws on two observations: (1) tinnitus probably arises from altered activity within the central auditory system following hearing loss and (2) sound-based training can change central auditory activity. Training that provides sound enrichment across hearing loss frequencies has therefore been hypothesised to alleviate ...
Egloff Deborah - - 2012
Building on previous findings, the project reported here expands on the idea of how the modality of touch contributes to the sensory perception of sound in the presence of vibro-tactile events. The SenseAble1.0, a vibrotactile interface, was developed to transform the auditory parameter space into one that is adequate for ...
Maas Edwin - - 2012
PURPOSE: To examine the role of feedback frequency in treatment for childhood apraxia of speech (CAS). Reducing the frequency of feedback enhances motor learning, and recently such feedback frequency reductions have been recommended for treatment of CAS. However, no published studies have explicitly compared different feedback frequencies in this population. ...
Wijnen Frank - - 2012
PURPOSE: A recent hypothesis ascribes dyslexia to a perceptual anchoring deficit. Supporting results have so far been obtained only in children with dyslexia and additional learning difficulties, but the hypothesis has been argued to apply to all dyslexics. METHOD: We measured auditory frequency discrimination thresholds in 54 young adults (native ...
Jones Peter M - - 2012
Previous experiments demonstrate a normal decline in unconditioned responding in rats with perirhinal cortex lesions but attenuated performance on spontaneous object recognition (SOR), a finding supporting the assertion that distinct systems support these phenomena. This finding informs on the nature of these two fundamental forms of learning and may be ...
Secora Kristen R - - 2012
Singing in songbirds is a complex, learned behavior which shares many parallels with human speech. The avian vocal organ (syrinx) has two potential sound sources, and each sound generator is under unilateral, ipsilateral neural control. Different songbird species vary in their use of bilateral or unilateral phonation (lateralized sound production) ...
Harding Glen - - 2012
The luminance and colour gradients across an image are the result of complex interactions between object shape, material and illumination. Using such variations to infer object shape or surface colour is therefore a difficult problem for the visual system. We know that changes to the shape of an object can ...
Tsuchiai Taiga - - 2012
We usually perceive things in our surroundings as unchanged despite viewpoint changes caused by self-motion. The visual system therefore must have a function to process objects independently of viewpoint. In this study, we examined whether viewpoint-independent spatial layout can be obtained implicitly. For this purpose, we used a contextual cueing ...
Vogel Edgar H - - 2012
The purpose of this study was to examine whether the progressive disappearance of short-latency conditioned responses, or inhibition of delay, observed in Pavlovian conditioning with long inter-stimulus intervals, could be reverted by the presentation of a novel stimulus. In one experiment, two groups of rabbits received extensive training with a ...
Balkenius Anna A Division of Chemical Ecology, Department of Plant Protection Biology, Swedish Agricultural University, Alnarp, Sweden. - - 2012
The mushroom bodies of the insect brain play an important role in olfactory processing, associative learning and memory. The mushroom bodies show odor-specific spatial patterns of activity and are also influenced by visual stimuli. Functional imaging was used to investigate changes in the in vivo responses of the mushroom body ...
Laudner Kevin G - - 2011
CONTEXT: Posterior shoulder tightness has been associated with altered shoulder range of motion (ROM) and several pathologic entities among baseball players. This tightness is hypothesized to be the result of the cumulative stress placed on the posterior shoulder during the deceleration phase of the throwing motion. The role of the ...
Rastogi Amit A University of Kansas School of Medicine, Veterans Affairs Medical Center, Kansas City, Missouri 64128-2295, USA. - - 2011
Missing adenomas and the inability to accurately differentiate between polyp histology remain the main limitations of standard-definition white-light (SD-WL) colonoscopy. To compare the adenoma detection rates of SD-WL with those of high-definition white-light (HD-WL) and narrow-band imaging (NBI) as well as the accuracy of predicting polyp histology. Multicenter, prospective, randomized, ...
Dupré Sandrine M - - 2011
In mammals, the nocturnal melatonin signal is well established as a key hormonal indicator of seasonal changes in day-length, providing the brain with an internal representation of the external photoperiod. The pars tuberalis (PT) of the pituitary gland is the major site of expression of the G-coupled receptor MT1 in ...
Ye Yan - - 2011
We propose a polarizing color filter based on a one-dimensional subwavelength metal-dielectric grating combining the functions of a polarizer and a color filter. The proposed device consists of three parts: a substrate, a dielectric grating, and a metal grating. The effects of the dielectric grating and the metal grating are ...
Delcea Mihaela - - 2011
Review of basic principles and recent developments in the area of stimuli responsive polymeric capsules and nanoshells formed via layer-by-layer (LbL) is presented. The most essential attributes of the LbL approach are multifunctionality and responsiveness to a multitude of stimuli. The stimuli can be logically divided into three categories: physical ...
Homberg Uwe - - 2011
Many animals rely on a sun compass for spatial orientation and long-range navigation. In addition to the Sun, insects also exploit the polarization pattern and chromatic gradient of the sky for estimating navigational directions. Analysis of polarization-vision pathways in locusts and crickets has shed first light on brain areas involved ...
Dacke M - - 2011
Prominent in the sky, but not visible to humans, is a pattern of polarized skylight formed around both the Sun and the Moon. Dung beetles are, at present, the only animal group known to use the much dimmer polarization pattern formed around the Moon as a compass cue for maintaining ...
Pignatelli Vincenzo - - 2011
Aquatic habitats are rich in polarized patterns that could provide valuable information about the environment to an animal with a visual system sensitive to polarization of light. Both cephalopods and fishes have been shown to behaviourally respond to polarized light cues, suggesting that polarization sensitivity (PS) may play a role ...
Macedo Antonio F - - 2011
To assess the effect on visual acuity of compensating fixation instability by controlling retinal image motion in people with macular disease. Ten patients with macular disease participated in this study. Crowded and noncrowded visual acuity were measured using an eye tracking system to compensate for fixation instability. Four conditions, corresponding ...
Wang Jianying - - 2011
The inverse opal hydrogel heterostructure (polyacrylamide (PAAm) (left side)-polyacrylic acid (PAA)/PAAm interpenetrating polymer network (IPN) (right side) is created by colloidal crystal templating. The two parts, PAAm and IPN, appear different structural colors due to the varied lattice constants and solvent response behaviors. The IPN part keeps red color and ...
David Nicole - - 2010
Individuals with autism often show a fragmented way of perceiving their environment, suggesting a disorder of information integration, possibly due to disrupted communication between brain areas. We investigated thirteen individuals with high-functioning autism (HFA) and thirteen healthy controls using the metastable motion quartet, a stimulus consisting of two dots alternately ...
Kayser Andrew S AS Department of Neurology, University of California, San Francisco, Emeryville, CA 94608, USA. - - 2010
Although perceptual decision making activates a network of brain areas involved in sensory, integrative, and motor functions, circuit activity can clearly be modulated by factors beyond the stimulus. Of particular interest is to understand how the network is modulated by top-down factors such as attention. Here, we demonstrate in a ...
Ethofer Thomas - - 2011
Human gaze is a critical social cue that can reveal intentions and dispositions of others. The right posterior superior temporal sulcus (pSTS) is thought to be critically involved in processing eye gaze information. We combined diffusion tensor imaging (DTI) and functional magnetic resonance imaging (fMRI) to identify direct neural connections ...
Cavalcante Larissa Maria - - 2011
To investigate the surface integrity of solvent-challenged ormocer-matrix composites, photoactivated by different light exposure modes, through surface-hardness measurements at different periods of time; and to compare such behavior with dimethacrylate-based materials. One hundred percent ormocer-based matrix (experimental ormocer (ORM)), a commercial mixed dimethacrylate-ormocer-based matrix (Admira (ADR)) and two commercial dimethacrylate-based ...
Pilz Karin S - - 2011
A highly familiar type of movement occurs whenever a person walks towards you. In the present study, we investigated whether this type of motion has an effect on face processing. We took a range of different 3D head models and placed them on a single, identical 3D body model. The ...
Benassi Mariagrazia - - 2010
The magnitude of the association between developmental dyslexia (DD) and motion sensitivity is evaluated in 35 studies, which investigated coherence motion perception in DD. A first analysis is conducted on the differences between DD groups and age-matched control (C) groups. In a second analysis, the relationship between motion coherence threshold ...
Teramoto Wataru - - 2010
In representational momentum (RM), the final position of a moving target is mislocalized in the direction of motion. Here, the effect of a concurrent sound on visual RM was demonstrated. A visual stimulus moved horizontally and disappeared at unpredictable positions. A complex tone without any motion cues was presented continuously ...
Saygin Ayse Pinar AP Department of Cognitive Science, University of California San Diego, La Jolla, CA 92093-0515, USA. - - 2010
Can linguistic semantics affect neural processing in feature-specific visual regions? Specifically, when we hear a sentence describing a situation that includes motion, do we engage neural processes that are part of the visual perception of motion? How about if a motion verb was used figuratively, not literally? We used fMRI ...
Pratt Jay - - 2010
Across humans' evolutionary history, detecting animate entities in the visual field (such as prey and predators) has been critical for survival. One of the defining features of animals is their motion-self-propelled and self-directed. Does such animate motion capture visual attention? To answer this question, we compared the time to detect ...
Bogadhi Amarender R - - 2011
Accuracy in estimating an object's global motion over time is not only affected by the noise in visual motion information but also by the spatial limitation of the local motion analyzers (aperture problem). Perceptual and oculomotor data demonstrate that during the initial stages of the motion information processing, 1D motion ...
Koh Hwan Cui HC Department of Psychology, University of Sheffield, Sheffield, South Yorkshire, United - - 2010
The magnocellular (M) pathway hypothesis proposes that impaired visual motion perception observed in individuals with Autism Spectrum Disorders (ASD) might be mediated by atypical functioning of the subcortical M pathway, as this pathway provides the bulk of visual input to cortical motion detectors. To test this hypothesis, we measured luminance ...
Kreitewolf Jens - - 2011
The onset of motion in an otherwise continuous sound elicits a prominent auditory evoked potential, the so-called motion onset response (MOR). The MOR has recently been shown to be modulated by stimulus-dependent factors, such as velocity, while the possible role of task-dependent factors has remained unclear. Here, the effect of ...
Debono Kurt - - 2010
Humans use smooth pursuit eye movements to track moving objects of interest. In order to track an object accurately, motion signals from the target have to be integrated and segmented from motion signals in the visual context. Most studies on pursuit eye movements used small visual targets against a featureless ...
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