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Results 301 - 350 of 806
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Lütkenhöner Bernd - - 2008
In many studies of auditory-evoked responses to low-intensity sounds, the response amplitude appears to increase roughly linearly with the sound level in decibels (dB), corresponding to a logarithmic intensity dependence. But the auditory system is assumed to be linear in the low-intensity limit. The goal of this study was to ...
Yilmaz Hasan - - 2008
The intensity of the sunlight reflected by the snow-covered surfaces is so high that it may disturb humans many times. This study aims to determine the reflected sunlight intensities from snow covered areas at points near (at a distance of 2 m) and under an individual tree and among trees ...
Rieger Dirk - - 2007
The light preferences of fruit flies were tested by 2 different means. First, flies were allowed to choose between different illuminations, and their favorite resting, grooming, and feeding places were determined with an infrared-sensitive camera. Second, the activity levels of the animals during their main daily activity period were determined ...
Quedas Araken - - 2007
Parkinson's disease affects the central nervous system resulting in voice quality alterations. It is typically resistant to drug therapy and often persists despite extensive behavioural speech and language therapy. Previous findings show that masking noise will produce a consistent increase in voice intensity in most normal individuals (Lombard's effect). AIM: ...
Bergadano Alessandra - - 2007
OBJECTIVE: To investigate the facilitation of the nociceptive withdrawal reflex (NWR) by repeated electrical stimuli and the associated behavioral response scores in conscious, nonmedicated dogs as a measure of temporal summation and analyze the influence of stimulus intensity and frequency on temporal summation responses. ANIMALS: 8 adult Beagles. PROCEDURES: Surface ...
Picton Terence W - - 2007
OBJECTIVE: To record steady-state responses to amplitude-modulated tones that change their intensity over time and to see how well behavioral thresholds can be estimated from such responses. DESIGN: The intensity of the stimuli used in this experiment increased from 25 to 75 dB SPL for 8 sec and then decreased ...
Zhang Na - - 2007
Recently, we have demonstrated that the fine-digit topography (millimeter sized) previously identified in the primary somatosensory cortex (SI), using electrophysiology and intrinsic signal optical imaging, can also be mapped with submillimeter resolution using blood-oxygenation-level-dependent (BOLD) functional magnetic resonance imaging at high field. In the present study, we have examined the ...
Andrus Amanda K - - 2007
Prepulse inhibition (PPI) of the auditory startle response (ASR) is a behavioral test that has been used to measure auditory thresholds, to assess sensory-motor integration functions, and its use has been recommended in the United States Environmental Protection Agency Developmental Neurotoxicity Guideline (OPPTS 870.6300). The purpose of the present study ...
Sato Akira - - 2007
Time-resolved UV resonance Raman (UVRR) spectroscopic studies of WT and mutant myoglobin were performed to reveal the dynamics of protein motion after ligand dissociation. After dissociation of carbon monoxide (CO) from the heme, UVRR bands of Tyr showed a decrease in intensity with a time constant of 2 ps. The ...
Turgut Altan - - 2007
Waveguide invariant theory is used to describe the frequency shifts of constant acoustic intensity level curves in broadband signal spectrograms measured at the New Jersey Shelf during the winter of 2003. The broadband signals (270-330 Hz) were transmitted from a fixed source and received at three fixed receivers, located at ...
Nishiyama Tomoki - - 2007
BACKGROUND: I investigated the effects of steam sterilization on light intensity of reusable fiberoptic laryngoscope blades. METHODS: Six new reusable fiberoptic Macintosh laryngoscope blades were steam sterilized. The light intensity was measured, the tip of the blades was photographed, and the light intensity of six new plastic disposable Macintosh laryngoscope ...
Sagi Elad - - 2007
It is well known that discrimination response variability increases with stimulus intensity, closely related to Weber's Law. It is also an axiom that sensation magnitude increases with stimulus intensity. Following earlier researchers such as Thurstone, Garner, and Durlach and Braida, we explored a new method of exploiting these relationships to ...
Harris Kelly C - - 2007
When measured behaviorally, older adults with normal hearing have poorer intensity discrimination thresholds than younger adults, but only at lower frequencies. Poor intensity discrimination at lower but not higher frequencies for older adults can be associated with an age-related decline in temporal processing. The current study was designed to assess ...
Nissfolk Jarl - - 2006
The transport and recombination of electrons in dye-sensitized TiO(2) solar cells were studied by analysis of the current and voltage response to a small square-wave light-intensity modulation. Solar cells were studied under working conditions by using potentiostatic and galvanostatic conditions. An increase in applied voltage, that is, from 0 V ...
Cassidy Iris - - 2006
The influence of visible light on the velocities of spiral waves in the [Ru(bpy)](3)(2+) -catalyzed Belousov-Zhabotinsky (BZ) reaction is well documented. However, there are only few reports showing the effect of the way a change in the applied intensity is made, or on "desensitization" or "memory" type phenomena. In this ...
Henderson R D - - 2006
The behavior and stability of motor units (MUs) in response to electrical stimulation of different intensities can be assessed with the stimulus-response curve, which is a graphical representation of the size of the compound muscle action potential (CMAP) in relation to stimulus intensity. To examine MU characteristics across the whole ...
Kuksenok Olga - - 2006
Using computer simulations, we establish an approach for creating defect-free, periodically ordered polymeric materials. The system involves ABC ternary mixtures where the A and B components undergo a reversible photochemical reaction. In addition, all three components are mutually immiscible and undergo phase separation. Through the simulations, we model the effects ...
Ran B - - 2006
We have experimentally and theoretically compared intensity and phase measurements of surface plasmon resonance, in order to check the widely claimed superiority of the phase method. Both experiment and theory show a slightly higher sensitivity for intensity detection. Simulations confirm that this result is generally true for a wide range ...
Yakuphanoglu F - - 2006
Photovoltaic properties of Au/beta-carotene/n-Si organic solar cells characterized by current-voltage and capacitance-voltage measurements have been investigated. The photocurrent in the reverse direction increases with increasing illumination intensity. The I(sc) increases linearly with light intensity. The I(sc) dependence of light intensity follows a power law I(sc) approximately F(alpha). The exponent alpha ...
Rodriguez Rosendo A - - 2006
OBJECTIVE: The application of intensity thresholds for embolus detection with transcranial Doppler (TCD) can exclude from analysis an unrecognized proportion of high-intensity transient signals (HITS))whose intensities are below the threshold. The lack of consistent threshold criteria between clinical trials may explain part of the discrepancy in the reported HITS counts. ...
Cheplick Gregory P - - 2006
The invasive grass Microstegium vimineum grows in low light beneath the canopy of eastern forests in North America by reiteration of modules (phytomers) along a tiller. Basal phytomers are vegetative; terminal phytomers produce a raceme of chasmogamous (CH) spikelets plus an axillary raceme of cleistogamous (CL) spikelets. Additional subterminal phytomers ...
Huisstede J H G - - 2006
We have developed a two-LED wobbler system to generate the spatial displacement of total light intensity on a detector surface, facilitating the acquisition of frequency responses up to 600 kHz with high accuracy. We have used this setup to characterize the low-pass filtering behavior of silicon-based position detectors for wavelengths ...
Toyokura Minoru - - 2006
Repeated stimulation of the sympathetic skin response (SSR) causes habituation. The aim of this study was to determine the effects of electrical stimulus intensity on SSR in 40 healthy controls (mean age+/-SD, 28.0+/-6.7 years). Electrical stimuli at three intensities (5, 15 and 30 mA) were applied to the median nerve ...
Biele Cezary C Warsaw School of Social Psychology, ul. Chodakowska 19/31, 03-815 Warsaw, Poland. - - 2006
Most research on the perception of emotional expressions is conducted using static faces as stimuli. However, facial displays of emotion are a highly dynamic phenomenon and a static photograph is its very unnatural representation. The goal of the present research was to assess the role of stimuli dynamics as well ...
Kelber, Almut
A crepuscular or nocturnal lifestyle has evolved in bees several times independently, probably to explore rewarding pollen sources without competition and to minimize predation and nest parasites. Despite these obvious advantages, only few bee species are nocturnal. Here we show that the sensitivity of the bee apposition eye is a ...
Sprengelmeyer Reiner - - 2006
It is well known from everyday experience, that facial expressions of emotions can very much vary in intensity, e.g. ranging from mild anger to rage, or from uneasiness and mild fear to angst and panic. However, the effect of different intensities of facial expressions of emotion on event related potentials ...
Venugopal V - - 2006
The influence of high light intensity on the growth and pigment accumulating ability of Anabaena azollae was investigated. A. azollae responded positively to high light intensity (6 klx) and was further evaluated at higher intensities (10 and 15 klx), in the presence of glucose, sucrose and jaggery +/- DCMU. Significant ...
Behnajady M A - - 2006
The potential of a common semiconductor, ZnO, has been explored as an effective catalyst for the photodegradation of C.I. Acid Yellow 23 (AY23). The effects of process parameters such as, catalyst loading, initial dye concentration, light intensity, and pH on the extent of photodegradation have been investigated. Substantial reduction of ...
Wright Geraldine A - - 2005
The fact that most types of sensory stimuli occur naturally over a large range of intensities is a challenge to early sensory processing. Sensory mechanisms appear to be optimized to extract perceptually significant stimulus fluctuations that can be analysed in a manner largely independent of the absolute stimulus intensity. This ...
Herz Natasha L - - 2005
PURPOSE: To determine the effect of photochromatic modulation with tinted lenses on the sensory symptoms of photophobia in blepharospasm patients. DESIGN: Nonrandomized case-control study. PARTICIPANTS: Thirty-four subjects (24 benign essential blepharospasm patients and 10 normal controls). METHODS: Subjects were seated in front of a calibrated light source. Beginning at 0%, ...
Thomas Biju B - - 2005
Multi-unit visual responses to light intensities ranging from -6.46 to 0.81 logcd/m2 were recorded from the surface of the superior colliculus of dark-adapted normal pigmented and normal albino rats. Light sensitivity was significantly higher in albinos. The response onset latency was inversely proportional to the stimulus intensity. The progression of ...
Gao Jiangtao - - 2005
Fluctuating light intensity had a more significant impact on growth of gametophytes of transgenic Laminaria japonica in a 2500 ml bubble-column bioreactor than constant light intensity. A fluctuating light intensity between 10 and 110 microE m(-2) s(-1), with a photoperiod of 14 h:10 h light:dark, was the best regime for ...
Amarie Dragos - - 2005
A general method to map the 3D spatial distribution of light emerging from nanoscale apertures is presented that uses photolithographic techniques to create polymer replicas of the intensity distribution. The resulting features varied with aperture diameter and exposure time and showed good correlation with theory. This method provides direct visualization ...
Kissick Michael W - - 2005
The interplay between a constant scan speed and intrafraction oscillatory motion produces interesting fluence intensity modulations along the axis of motion that are sensitive to the motion function, as originally shown in a classic paper by Yu et al. [Phys. Med. Biol. 43, 91-104 (1998)]. The fluence intensity profiles are ...
Ekkekakis Panteleimon - - 2005
A model for systematic changes in patterns of inter-individual variation in affective responses to physical activity of varying intensities is presented, as a conceptual alternative to the search for a global dose-response curve. It is theorized that trends towards universality will emerge in response to activities that are either generally ...
Fuchs Paul Albert - - 2005
The activity of individual afferent neurones in the mammalian cochlea can be driven by neurotransmitter released from a single synaptic ribbon in a single inner hair cell. Thus, a ribbon synapse must be able to transmit all the information on sound frequency, intensity and timing carried centrally. This task is ...
Mihailetchi V D - - 2005
In 1971 Goodman and Rose predicted the occurrence of a fundamental electrostatic limit for the photocurrent in semiconductors at high light intensities. Blends of conjugated polymers and fullerenes are an ideal model system to observe this space-charge limit experimentally, since they combine an unbalanced charge transport, long lifetimes, high charge ...
Zhou Lu-Qun - - 2005
We observe N:(N-1)(N>/=2) frequency-locking phenomena of propagating wave fronts when increasing the light intensity in a spatially extended system. The experiments were carried out using the light-sensitive form of the Belousov-Zhabotinsky reaction with Ru(bpy)(2+)3 as a catalyst. By constructing a mapping function, the characteristic devil's staircase can be reproduced when ...
Baca Serapio M - - 2005
In response to touches to their skin, medicinal leeches shorten their body on the side of the touch. We elicited local bends by delivering precisely controlled pressure stimuli at different locations, intensities, and durations to body-wall preparations. We video-taped the individual responses, quantifying the body-wall displacements over time using a ...
Barbosa Maria J - - 2005
Acceleration-stat (A-stat) cultivations in which the dilution rate is continuously changed at a constant acceleration rate, leading to different average light intensities inside the photobioreactor, can supply more information and reduce experimental time compared with chemostat cultivations. The A-stat was used to optimize the biomass and product yield of continuous ...
Koster, L.J.A.
The open-circuit voltage Voc of polymer:fullerene bulk heterojunction solar cells is investigated as a function of light intensity for different temperatures. Devices consisted of a blend of a poly (p-phenylene vinylene) derivative as the hole conductor and 6,6-phenyl C61-butyric acid methyl ester as the electron conductor. The observed photogenerated current ...
Koster, L.J.A.
A typical feature of polymer/fullerene based solar cells is that the current density under short-circuit conditions (Jsc) does not scale exactly linearly with light intensity (I). Instead, a power law relationship is found given by Jsc∝I^α, where αranges from 0.85 to 1. In a number of reports this deviation from ...
K. Taheri Abkenar
</I>The influence of light condition on quality and quantity characteristics of beech sapling (<I>Fagus orientalis </I>Lipsky) was studied in Sefidab (North of Iran). Beech forest growing in mountain region (1250-1450 m.a.s.l) of Iran. The experimental plots were establish in regenerations gaps resulting from natural regeneration. With each gaps, 9 sample ...
Cheng Andrew Y S - - 2004
Measurement of the atmospheric concentration of nitrogen dioxide (NO(2)) pollutant was demonstrated by differential optical absorption spectroscopy (DOAS) using a visible acousto-optic tunable filter. In a traditional spectral scanning DOAS system for atmospheric concentration monitoring, a highly stable light source is required. When the light intensity fluctuates during scanning, the ...
do Nascimento Patrícia Maria - - 2004
OBJECTIVE: The objective of the present investigation was to assess the histological effects of different wavelengths and intensities on the healing process of cutaneous wounds. BACKGROUND DATA: Tissue repair is a dynamic interactive process which involves mediators, cells and extra-cellular matrix. Several reports on the use of laser therapy have ...
Pangrsic Tina - - 2005
We measured the oxygen (O2) consumption of isolated blowfly eyes using a magnetic diver balance, a device for high-resolution volumetric O2 consumption measurements. The light-induced O2 consumption is at most three times the value of the dark consumption, which is 0.6 nl O2 s(-1) eye(-1), and is in good agreement ...
Laurinavichene Tatyana - - 2004
The effect of light intensity on hydrogen production by sulfur-deprived Chlamydomonas reinhardtii was studied in situ using either long- or short-term experiments, or alternatively, with samples withdrawn from the photobioreactor. Overall hydrogen production by S-deprived culture was shown to depend on the light intensity and to exhibit regions of light ...
Bartoshuk L M - - 2004
Labeled scales are commonly used for across-group comparisons. The labels consist of adjective/adverb intensity descriptors (e.g., "very strong"). The relative distances among descriptors are essentially constant but the absolute perceived intensities they denote vary with the domain to which they are applied (e.g., a "very strong" rose odor is weaker ...
Mostafa Hamdy I A - - 2004
The first and second derivatives of dielectric spectra have evidenced the existence of two interacting states of purple membrane (PM) that respond differently to the intensity of illuminating light providing, this way, underlying consequences to the heterogeneous behavior of bacteriorhodopsin (bR). It is of particular interest to note that the ...
Ditlbacher H - - 2004
We describe a surface plasmon polariton- (SPP-) based device for measuring the intensity distribution of strongly focused light beams. A gold thin film configured as a sharp step is positioned in the focal region of a light beam, converting light into SPPs. The SPPs emit directional leakage radiation into the ...
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