Search Results
Results 151 - 200 of 1745
1 2 3 4 5 6 7 8 9 10 >
Dion Laurie-Anne - - 2013
Visual evoked potentials (VEPs) are known to be influenced by several biological variables, including sex. In adult populations studies using conventional high-contrast checkerboard have shown that females display larger amplitudes and shorter latencies than males. To date, few studies have been conducted in children; the available data suggests that girls ...
Hirtenlehner Stefan S Zoology, Karl-Franzens-University, Universitätsplatz 2, 8010 Graz, Austria. - - 2013
Subtle random deviations from perfect symmetry in bilateral traits are suggested to signal reduced phenotypic and genetic quality of a sender, but little is known about the related receiver mechanisms for discriminating symmetrical from asymmetrical traits. Here, we investigated these mechanisms in behavioural and neurophysiological experiments in the Mediterranean field ...
Defrancesco Michaela - - 2013
INTRODUCTION: Tryptophan depletion (TD) is an established method to influence the serotonergic system and mood. The purpose of this study was to examine the effect of TD under different ambient light conditions, measured through serotonin-associated plasma levels and a visual analog scale (VAS), on healthy females. METHODS: Thirty-eight healthy female ...
Lea-Smith David J - - 2013
Cyanobacteria perform photosynthesis and respiration in the thylakoid membrane, suggesting that the two processes are interlinked. However the role of the respiratory electron transfer chain under natural environmental conditions has not been established. Through targeted gene disruption mutants of Synechocystis sp. PCC 6803 were generated that lacked combinations of the ...
Cockrem John F - - 2013
Birds can respond to an internal or external stimulus with activation of the HPA axis and secretion of corticosterone. There is considerable individual variation in corticosterone responses, and individual responses can be very different from the mean response for a group of birds. Corticosterone responses and behavioural responses to environmental ...
Condello Giancarlo - - 2013
The aim of the current study was to investigate the relationship between straight-sprint and change-of-direction performance. Total sprinting time and split time at 5 m were collected from 44 college football players during a 15-m straight sprint (SS15m) and a 15-m zigzag sprint with two 60° changes of direction (COD15m). ...
Esformes Joseph I - - 2013
ABSTRACT: Postactivation potentiation (PAP) refers to increased muscular force generation following previous muscular activity. Various studies have used different squat variations as a PAP stimulus; however, different squat depths can have different mechanical and physiological demands that could yield different PAP levels and subsequent performance. The study aimed to compare ...
Xing X Y - - 2013
In common with human speech, song is culturally inherited in oscine passerine birds ('songbirds'). Intraspecific divergence in birdsong, such as development of local dialects, might be an important early step in the speciation process. It is therefore vital to understand how songs diverge, especially in founding populations. The northward expansion ...
Crino Ondi L - - 2013
Roads have been associated with behavioral and physiological changes in wildlife. In birds, roads decrease reproductive success and biodiversity and increase physiological stress. Although the consequences of roads on individuals and communities have been well described, the mechanisms through which roads affect birds remain largely unexplored. Here, we examine one ...
Tanikawa Hidenori - - 2013
It has been suggested that non-contact anterior cruciate ligament injury commonly occurs during sports requiring acute deceleration or landing motion and that female athletes are more likely to sustain the injury than male athletes. The purpose of this study was to make task-to-task and male-female comparisons of knee kinematics and ...
Markham Michael R - - 2013
Some gymnotiform electric fish species rapidly modify their electric signal waveforms by altering the action potential (AP) waveforms of their electrocytes, the excitable cells that produce the Electric Organ Discharge (EOD). The fish Brachyhypopomus gauderio alters EOD amplitude and pulse duration as a social signal in accordance with the prevailing ...
Walker Leila K LK Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK. - - 2013
It is well established that the expression of many ornamental traits is dependent on the current condition of the bearer. However, conditions experienced in early life are also known to be important for an individual's subsequent fitness and therefore, directly or indirectly, for the fitness of their mate. Specifically, a ...
Dominoni Davide D Department of Migration and Immuno-ecology, Max Planck Institute for Ornithology, Radolfzell 78315, Germany. - - 2013
Artificial light at night is a rapidly increasing phenomenon and it is presumed to have global implications. Light at night has been associated with health problems in humans as a consequence of altered biological rhythms. Effects on wild animals have been less investigated, but light at night has often been ...
Yan Nan - - 2013
The present study examined the possible relationship between classification of professional singing voices and their vocal tract parameters including vocal tract length and volume, and vowel formant frequencies. Acoustic reflection technology (ART) was used to measure vocal tract length and volume of 107 professional singers: 32 tenors, 25 baritones, 27 ...
Howarth Samuel J - - 2013
Sustained maximum lumbar spine flexion can increase the angle at which the low back flexion relaxation phenomenon (FRP) is observed. This adaptation has been hypothesized to have implications for the control of lumbar spine stability and increase the potential for low back injury. The objective of this study was to ...
Sheaves M - - 2013
The reproductive periodicity of the sparid, Acanthopagrus pacificus, over four temporal scales is described. Acanthopagrus pacificus had a short spawning season between June and September, and within this, a peak reproductive period from July to early September. During the peak period there were several spawning peaks corresponding to a lunar ...
Jensen Peña Catherine C Department of Psychology, Columbia University, New York, NY 10027, - - 2013
Previous studies in Long-Evans rats demonstrated a significant relationship between variation in pup licking/grooming and arched-back nursing (LG-ABN) and offspring development. However, maternal care is dynamic and exhibits significant temporal variation. In the current study, we assessed temporal variation in LG and ABN in lactating rats across the circadian cycle ...
Gall Megan D MD Neuroscience Institute, Georgia State University, 100 Piedmont Avenue SE, Atlanta, GA 30303, USA. - - 2013
Many species of songbirds exhibit dramatic seasonal variation in song output. Recent evidence suggests that seasonal changes in auditory processing are coincident with seasonal variation in vocal output. Here, we show, for the first time, that frequency selectivity and temporal resolution of the songbird auditory periphery change seasonally and in ...
Woo J H JH Department of Rehabilitation Therapy, Hallym University, - - 2013
The axe kick, in Olympic style taekwondo, has been identified as the most popular scoring technique aimed to the head during full contact competition. The first purpose of this study was to identify and investigate design issues with the current World Taekwondo Federation approved chest protector. A secondary purpose was ...
Chien Hui-Lien - - 2013
High-heeled shoes are associated with instability and falling, leading to injuries such as fracture and ankle sprain. Knowledge of the motion of the body's center of mass (COM) with respect to the center of pressure (COP) during high-heeled gait may offer insights into the balance control strategies and provide a ...
Jones Patricia L - - 2013
The mating calls of male túngara frogs, Physalaemus pustulosus, attract intended (conspecific females) and unintended (eavesdropping predators and parasites) receivers. The calls are complex, having two components: a frequency-modulated "whine" followed by 0-7 harmonic bursts or "chucks". The whine is necessary and sufficient to elicit phonotaxis from females and the ...
Mobarkey Nader - - 2013
Photostimulation of retinal photoreceptors appears to inhibit reproductive activity in birds. In the present study, the involvement of serotonin and vasoactive intestinal peptide was investigated in relation to reproductive failure associated with retinal photostimulation. Hens at 23 wk of age were divided into six rooms equipped with individual cages. At ...
Akenhead Richard - - 2013
OBJECTIVES: This study examined distances covered at low (1-2ms(-2)), moderate (2-3ms(-2)) and high (>3ms(-2)) acceleration (L(ACC), M(ACC) and H(ACC) respectively) and deceleration (L(DEC), M(DEC), and H(DEC) respectively) during competitive football games. Temporal and transient patterns of acceleration and deceleration were also examined. DESIGN: Observational, repeated measures. METHODS: Thirty-six professional male ...
Gonzalez-Voyer A - - 2013
The study of animal communication systems is an important step towards gaining greater understanding of the processes influencing diversification because signals often play an important role in mate choice and can lead to reproductive isolation. Signal evolution can be influenced by a diversity of factors such as biophysical constraints on ...
Canale A - - 2013
In this paper we describe acoustically the wing-fanning behaviour showed by the male of the braconid Psyttalia concolor towards females and other conspecific males. Psyttalia concolor is a synovigenic koinobiont larval-pupal endoparasitoid of many Tephritidae, used in olive crops to control the olive fruit fly, Bactrocera oleae. In this braconid ...
Hu Wei W Department of Molecular and Cellular Biology and Plant Biology, University of California, Davis, CA 95616, - - 2013
In view of the extensive literature on phytochrome mutants in the Ler accession of Arabidopsis, we sought to secure a phytochrome-null line in the same genetic background for comparative studies. Here we report the isolation and phenotypic characterization of phyABCDE quintuple and phyABDE quadruple mutants in the Ler background. Unlike ...
Thomas Stephen John - - 2013
CONTEXT: Pathologies such as anterior instability and impingement are common in baseball and have been linked to decreases in internal rotation (IR) and concurrent increases in external rotation (ER) motion. Additionally, alterations to scapular upward rotation have been identified in this population. OBJECTIVE: To measure glenohumeral (GH) IR and ER ...
Korpela Katri - - 2013
Small rodents are key species in many ecosystems. In boreal and subarctic environments, their importance is heightened by pronounced multiannual population cycles. Alarmingly, the previously regular rodent cycles appear to be collapsing simultaneously in many areas. Climate change, particularly decreasing snow quality or quantity in winter, is hypothesized as a ...
Dennenmoser Stefan - - 2013
Male fiddler crabs, genus Uca, have one greatly enlarged claw with which they court females and threaten and fight other males. Longer claws are more effective signals but are thought to be less effective weapons because the relative closing force at the tip of the claw decreases with claw length. ...
Longrie Nicolas - - 2013
BACKGROUND: Sound production is widespread among fishes and accompanies many social interactions. The literature reports twenty-nine cichlid species known to produce sounds during aggressive and courtship displays, but the precise range in behavioural contexts is unclear. This study aims to describe the various Oreochromis niloticus behaviours that are associated with ...
Schouten Ben - - 2013
The human visual system has evolved to be highly sensitive to visual information about other persons and their movements as is illustrated by the effortless perception of point-light figures or 'biological motion'. When presented orthographically, a point-light walker is interpreted in two anatomically plausible ways: As 'facing the viewer' or ...
Lee Jin - - 2013
The direction-reversal visual evoked potential (DR-VEP) latency is a key measure of the development of motion processing in infancy. However, the latency of this response has not been previously investigated. For other stimuli, both the latency of an initial peak and a latency measure calculated from steady-state phase as a ...
Raphael Sabine - - 2013
To find out whether there are separate visual mechanisms for size, density, and numerosity computation in textures, we investigated the ability of human observers both to discriminate differences in numerosity between approximately circular textures and to decide whether the differences were due to a change in circle size or dot ...
Berman Tali S - - 2013
The adaptive significance of discontinuous gas exchange cycles (DGC) in insects is contentious. Based on observations of DGC occurrence in insects of typically large brain size and often socially-complex life history, and spontaneous DGC in decapitated insects, the neural hypothesis for the evolution of DGC was recently proposed. It posits ...
Bredlau Justin P - - 2013
Male parasitic wasps attract females with a courtship song produced by rapid wing fanning. Songs have been described for several parasitic wasp species; however, beyond association with wing fanning, the mechanism of sound generation has not been examined. We characterized the male courtship song of Cotesia congregata (Hymenoptera: Braconidae) and ...
Sindall Paul - - 2013
To examine the heart-rate (HR) response and court-movement variables during wheelchair tennis match play for high- (HIGH) and low- (LOW) performance-ranked players. Analysis of physiological and movement-based responses during match play offers an insight into the demands of tennis, allowing practical recommendations to be made. Fourteen male open-class players were ...
Menz Myles H M - - 2013
Pollinator behaviour directly affects patterns of pollen movement and outcrossing rates in plants. In orchids pollinated by sexual deception of insects, patterns of pollen movement are primarily determined by the mate-searching behaviour of the deceived males. Here, using a capture-mark-recapture study (CMR) and dietary analysis, we compare mate-searching behaviour in ...
Xu Yi - - 2013
Voice, as a secondary sexual characteristic, is known to affect the perceived attractiveness of human individuals. But the underlying mechanism of vocal attractiveness has remained unclear. Here, we presented human listeners with acoustically altered natural sentences and fully synthetic sentences with systematically manipulated pitch, formants and voice quality based on ...
Stanistreet Joy E - - 2013
Passive acoustic tracking provides an unobtrusive method of studying the movement of sound-producing animals in the marine environment where traditional tracking methods may be costly or infeasible. We used passive acoustic tracking to characterize the fine-scale movements of singing humpback whales (Megaptera novaeangliae) on a northwest Atlantic feeding ground. Male ...
Conklin Jesse R - - 2013
Flexibility in scheduling varies throughout an organism's annual cycle, reflecting relative temporal constraints and fitness consequences among life-history stages. Time-selection can act at different scales, either by limiting the range of alternative strategies in the population, or by increasing the precision of individual performance. We tracked individual bar-tailed godwits Limosa ...
Lin Che-Hung - - 2013
Brooding corals often exhibit daily planulation peaks in certain phases of lunar months during their reproductive season. The mechanism controlling this diurnal phenomenon, however, remains uncertain. Seriatopora hystrix populations of Southern Taiwan exhibit a highly synchronized planulation rhythm characterized by pre-dawn peak release episodes over a period of 4-6 days ...
Gilg Olivier - - 2013
The Long-tailed Skua, a small (<300 g) Arctic-breeding predator and seabird, is a functionally very important component of the Arctic vertebrate communities in summer, but little is known about its migration and winter distribution. We used light-level geolocators to track the annual movements of eight adult birds breeding in north-east ...
van Haren Hans - - 2013
Diel vertical migration (DVM) is a ubiquitous phenomenon in marine and freshwater plankton communities. Most commonly, plankton migrate to surface waters at dusk and return to deeper waters at dawn. Up until recently, it was thought that DVM was triggered by a relative change in visible light intensity. However, evidence ...
Pedroso Silvia S - - 2013
Acoustic signals can encode crucial information about species identity and individual quality. We recorded and compared male courtship drum sounds of the sand goby Pomatoschistus minutus and the painted goby P. pictus and examined if they can function in species recognition within sympatric populations. We also examined which acoustic features ...
Fayson Shirleeah D - - 2013
The purpose of this study was to determine the effects of Kinesio® taping on static restraint and dynamic postural control of the ankle joint. Thirty female subjects with no history of ankle injury participated in this study. Subjects were tested for passive ankle laxity and stiffness, and time to stabilization ...
Hoepfner Amanda R - - 2013
The courtship and dominance behavior of brown-headed cowbirds (Molothrus ater) consists of a multi-modal display, including song as well as postural and wing movements. The temporal sequences of the acoustic and the visual display are coordinated. In adult male cowbirds the largest wing movements of the display are synchronized with ...
Snyder Jessica M - - 2013
Over a 1-mo period, increased morbidity and mortality occurred in a flock of zebra finches (Taeniopygia guttata). Complete postmortem examination was performed on 6 of the affected birds, 4 of which subsequently were diagnosed with the avian gastric yeast previously known as megabacteriosis (Macrorhabdus ornithogaster). The remaining 2 birds were ...
Franke Robert - - 2013
Juvenile noble crayfish, Astacusastacus (Crustacea, Astacidea) in the second year of age were kept in the laboratory for a twelve-month period under continuing "summer conditions" (LD 16:8, 19°C). Molting processes in this population could be synchronized by artificial moonlight cycles. Peaks of exuviations occurred at "new moons". Males showed a ...
Phasuk Jumnongjit - - 2013
Knowledge of seasonal abundance and flight activity patterns are required to design effective management programs for insect pests of humans and livestock. In this study, the seasonality and daily flight activity of Stomoxys species were observed on two dairy farms in Saraburi Province, Thailand. Data were assessed throughout 1 year using ...
Steiger Silke S - - 2013
Circadian clocks are centrally involved in the regulation of daily behavioural and physiological processes. These clocks are synchronized to the 24 h day by external cues (Zeitgeber), the most important of which is the light-dark cycle. In polar environments, however, the strength of the Zeitgeber is greatly reduced around the ...
1 2 3 4 5 6 7 8 9 10 >