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Guerriero Erica - - 2012
The image shows an integrated graphene voltage amplifier, which paves the way for all-graphene analogue electronics. Signal amplification is obtained by fabricating graphene transistors in which the top gate overlaps with the source and drain contacts. This results in full-channel gating and therefore high transconductance at room temperature. The fabricated ...
Repp Bruno H - - 2012
Studies of phase correction in sensorimotor synchronization often introduce timing perturbations that are unpredictable with regard to direction, magnitude, and position in the stimulus sequence. If participants knew any or all of these parameters in advance, would they be able to anticipate perturbations and thus regain synchrony more quickly? In ...
Dron Anthony - - 2011
This study provides with original data sets on the physiology of the unicellular diazotrophic cyanobacterium Crocosphaera watsonii WH8501, maintained in continuous culture in conditions of obligate diazotrophy. Cultures were exposed to a 12:12 light-dark regime, representative of what they experience in nature and where growth is expected to be balanced. ...
Garo Florian - - 2011
Shedding light on DNA: A DNA-based light-harvesting antenna has been synthesized. Light is absorbed by π-stacked phenanthrene units and efficiently transferred to a phenanthrene-pyrene exciplex. The whole system is structurally organized by a DNA scaffold. Up to eight phenanthrene units are used for light collection and the intensity of the ...
Dedieu Philippe - - 2011
Mature locomotion in humans is characterized by an anti-phase coordination (moving in opposite directions) between the pelvic and the scapular girdles. This pattern involves a specific relationship between the arm and leg motion is deemed to be most flexible and dynamically efficient. Still, when the arms are involved in another ...
Nowaczewski S - - 2011
Pheasant eggs of different colors differ with regard to physical properties. This study was conducted to ascertain the intensity of infestation by microscopic fungi based on egg color. Settling intensity by microscopic fungi of pheasant egg shells and the content of eggs of different color during a 7-d storage period ...
Gao Peng - - 2011
Zernike phase contrast microscopy is extended and combined with a phase-shifting mechanism to perform quantitative phase measurements of microscopic objects. Dozens of discrete point light sources on a ring are constructed for illumination. For each point light source, three different levels of point-like phase steps are designed, which are alternatively ...
Ibsen Stuart D - - 2011
A previous comparative analysis of normalized click amplitude spectra from a Tursiops truncatus has shown that those frequencies with the lowest click-to-click variability in spectral content were the frequencies the animal paid attention to during target discrimination tasks. In that case, the dolphin only paid attention to the frequency range ...
Kristiansen Ulf R - - 2011
It is well known that airflow in a corrugated pipe can excite whistling at the frequencies of the pipe's longitudinal acoustic modes. This short contribution reports on the results of experiments where a low frequency, oscillating flow with velocity magnitudes of the same order as the airflow has been added. ...
Kerner Boris S - - 2011
Based on simulations of stochastic three-phase and two-phase traffic flow models, we reveal that at a signalized city intersection under small link inflow rates at which a vehicle queue developed during the red phase of the light signal dissolves fully during the green phase, i.e., no traffic gridlock should be ...
Sheean Geoffrey L - - 2011
Quantification in clinical, diagnostic electromyography (EMG) currently includes motor unit action potential (MUAP) analysis and interference pattern analysis. Early efforts to examine the frequency/power spectra of the interference pattern showed modest value but the technique was not developed further. This paper re-examines spectral analysis, extending it into the time-varying domain, ...
Dadesh Khaled M - - 2011
Multispectral photometry is often required to distinguish samples in flow injection analysis and flow cytometry; however, the cost of multiple light detectors, filters, and optical paths contribute to the high cost of multicolor and spectral detection systems. This paper describes frequency division multiplexing (FDM), a simple approach for performing multi-wavelength ...
Chan Calvin W Y - - 2011
Cross-correlation is often used as the primary technique to compare two biological signals. Cross-correlation is an effective means to measure the synchronization of two signals assuming the relative phases of all frequencies are distributed linearly, that is, a group delay. The group delay assumption imposes an unfavorable restriction on signals ...
Ding Yi - - 2011
Phase unwrapping is an important and challenging issue in fringe pattern profilometry. In this Letter we propose an approach to recover absolute phase maps of two fringe patterns with selected frequencies. Compared to existing temporal multiple frequency algorithms, the two frequencies in our proposed algorithm can be high enough and ...
Cardin Velia - - 2011
The principal visual cue to self-motion (egomotion) is optic flow, which is specified in terms of local 2D velocities in the retinal image without reference to depth cues. However, in general, points near the centre of expansion of natural flow fields are distant, while those in the periphery are closer, ...
Hajnal Alen - - 2011
Historically, the bodily senses have often been regarded as impeccable sources of spatial information and as being the teacher of vision. Here, the authors report that the haptic perception of slope by means of the foot is greatly exaggerated. The exaggeration is present in verbal as well as proprioceptive judgments. ...
Chamoun Georges C - - 2011
We explore whether vortex flows in the wake of a fixed circular cylinder can be stabilized using harmonic forcing. We use Föppl's point vortex model augmented with a harmonic point source-sink mechanism which preserves conservation of mass and leaves the system Hamiltonian. We discover a region of Lyapunov-stable vortex motion ...
Dhar Sumitrajit - - 2011
The phase versus frequency function of the distortion product otoacoustic emission (DPOAE) at 2f(1) - f(2) is approximately invariant at frequencies above 1.5 kHz in human subjects when recorded with a constant f(2)/f(1). However, a secular break from this invariance has been observed at lower frequencies where the phase-gradient becomes markedly steeper. ...
Abdala Carolina - - 2011
Scaling symmetry appears to be a fundamental property of the cochlea as evidenced by invariant distortion product otoacoustic emission (DPOAE) phase above ∼1-1.5 kHz when using frequency-scaled stimuli. Below this frequency demarcation, phase steepens. Cochlear scaling and its breaking have been described in the adult cochlea but have not been ...
Davis Chris - - 2011
Three experiments tested how the physical format and information content of forward and backward masks affected the extent of visual pattern masking. This involved using different types of forward and backward masks with target discrimination measured by percentage correct in the first experiment (with a fixed target duration) and by ...
Mizuno Misao - - 2011
Sensory rhodopsin II (SRII) is a negative phototaxis receptor containing retinal as its chromophore, which mediates the avoidance of blue-light. The signal transduction is initiated by the photoisomerization of the retinal chromophore, resulting in conformational changes of the protein which are transmitted to a transducer protein. To gain insight into ...
Chang Jer-Hao - - 2011
Introduction Hand impairment is a common and serious occupational injury among workers because it can affect the outcome to return to work (RTW) and even cause permanent dysfunction. The hand measures can directly describe the primary hand function and limitation. This study investigated the correlation of RTW and the overall ...
Yannopoulos Spyros N - - 2011
Massive photoinduced short- and medium-range structural changes (photopolymerization) in As-S glasses are induced by near-bandgap light and studied by Raman scattering. Structural changes involve bond restructuring in sulfur-rich nanodomains of these nanoscale-phase-separated glasses. The spectral dependence of the photopolymerization effect demonstrates that various wavelengths can be used to optically change ...
Kumamoto Yasuaki - - 2011
We employed deep UV (DUV) Raman spectroscopy for characterization of molecular photodamage in cells. 244 nm light excitation Raman spectra were measured for HeLa cells exposed to the excitation light for different durations. In the spectra obtained with the shortest exposure duration (0.25 sec at 16 µW/µm(2) irradiation), characteristic resonant ...
Dennis M A - - 2011
Flow cytometry has potential as a rapid assessment technique to evaluate phytoplankton biomass and species composition. It facilitates for multi-parameter analysis of individual cells on the basis of light scattering effects induced from cellular constituents, as well as auto-fluorescence. Fluorescence emission characteristics may be especially useful in classifying cyanobacteria as ...
Danion Frédéric - - 2010
Predicting the consequences of actions is fundamental for skilled motor behavior. We investigated whether motor prediction is influenced by the fact that some movements are easier to perform and stabilize than others. Twelve subjects performed a bimanual rhythmical task either symmetrically or asymmetrically (the latter being more difficult and less ...
Ingrey P C - - 2010
A slab of left-handed material (LHM) with refractive index -1 forms a perfect lens that retains subwavelength information about a source or object. Such lenses are highly susceptible to perturbations affecting their performance. It is shown that illuminating a roughened interface between air and an LHM produces a regime for ...
Sindhu Bhagwant Singh - - 2011
This was a prospective cohort study. In a previous study, the slopes of the force-time (F-T) curve were shown to differentiate between maximal and submaximal grip effort in healthy participants. The objective of the study was to examine if the slopes of the F-T curve can determine the sincerity of ...
Falk Tiago H - - 2010
A comprehensive understanding of the underlying biomechanical processes during handwriting is needed to accurately guide clinical interventions. To date, quantitative measurement of such biomechanical processes has largely excluded measurements of the forces exerted radially on the barrel of the writing utensil (grip forces) and how they vary over time during ...
King Emily C - - 2010
For a reach-to-grasp reaction to prevent a fall, it must be executed very rapidly, but with sufficient accuracy to achieve a functional grip. Recent findings suggest that the CNS may avoid potential time delays associated with saccade-guided arm movements by instead relying on peripheral vision (PV). However, studies of volitional ...
Cohen Rajal G - - 2011
People pick up objects in ways that reflect prospective as well as retrospective control. Prospective control is indicated by planning for end-state comfort such that people grasp a cylinder to be rotated or translated with a hand orientation or at a height that affords a comfortable final posture. Retrospective control ...
Vijayasai Ashwin P - - 2010
In this work, we describe the development and testing of a three degree of freedom meso/micromanipulation system for handling micro-objects, including biological cells and microbeads. Three-axis control is obtained using stepper motors coupled to micromanipulators. The test specimen is placed on a linear X-stage, which is coupled to one stepper ...
Singh Tarkeshwar - - 2010
We tested a hypothesis that fatigue of an element (a finger) leads to an adaptive neural strategy that involves an increase in force variability in the other finger(s) and an increase in co-variation of commands to fingers to keep total force variability relatively unchanged. We tested this hypothesis using a ...
Kapur Shweta - - 2010
We explored changes in finger interaction in the process of healthy aging as a window into neural control strategies of natural movements. In particular, we quantified the amount of force produced by noninstructed fingers in different directions, the amount of force produced by the instructed finger orthogonally to the task ...
Fujii Shinya - - 2010
Expert musicians show experience-dependent reduced asymmetry in the structure of motor-related brain areas and in the maximum tapping frequency between the hands. Therefore we hypothesized that a reduced hand-skill asymmetry is strongly related to rapid and rhythmical bimanual coordination and developed a dynamical model including a symmetry-breaking parameter Δω, for ...
Haddad Omid - - 2010
Trunk kinematics variables have been shown to be related to low back injury risk during lifting tasks and it was hypothesised that changes in hand-hold positions could influence trunk kinematics and thereby risk. Fourteen subjects lifted a 5 or 10 kg box using four different hand placement locations (two symmetric ...
Chang Hsiao-Yun - - 2010
To determine the immediate effects of applied forearm Kinesio taping on maximal grip strength and force sense of healthy collegiate athletes. Single group, repeated measures study. Clinical sports medicine laboratory at a university hospital. Twenty-one healthy collegiate athletes voluntarily participated in this study. All subjects were male (average height: 181.24 ± 7.60 cm; ...
Ho Hsin-Ni - - 2010
The thermal sense is diffuse and incapable of providing precise spatial information. From a phenomenon known as thermal referral, we know that touch influences the localization of cold or warmth, leading to our perceiving illusory thermal sensations at a thermally neutral site. This study investigated the frame of reference for ...
Adamec Jiri - - 2011
Impacts to the head are a common form of body violence and thus a relevant legal medical issue. Biomechanical assessment of injury potential has been traditionally based on qualitative analysis and experience. The aim of this study was to collect benchmark data that would facilitate the assessment of the maximum ...
Lewis Erika - - 2010
Intrarater and interrater reliability were determined for middle finger range of motion (ROM) using the Rolyan finger goniometer. Seven raters measured ROM 3 times (trials) on 20 healthy adults. Intraclass reliability analysis and analysis of variance was used to assess the consistency and stability of measures. Level of significance was ...
Hodselmans Audy P - - 2010
OBJECTIVE: Change in psychophysical capacity, calculated as the ratio between physical capacity and perceived effort, may be a determinant of change in perceived disability. The aim of this study was to identify determinants for change in perceived disability, as measured with the Roland Morris Disability Questionnaire (RMDQ), in patients with ...
Hermsdörfer Joachim - - 2011
Muscular hyperactivity during handwriting, irregular and jerky scripts, as well as awkward and slowed pen movements are the cardinal symptoms of writer's cramp. Accordingly, impaired kinematics and increased force have been reported in writer's cramp. However, the relationship between these symptoms has rarely been investigated. In addition, measurements of finger ...
Crevecoeur Frédéric - - 2010
During object manipulation, predictive grip force modulation allows compensation for inertial forces induced by the object's acceleration. This coupling between grip force (GF) and load force (LF) during voluntary movements has demonstrated high levels of complexity, adaptability, and flexibility under many loading conditions in a broad range of experimental studies. ...
Sarlegna Fabrice R - - 2010
When we manipulate an object, grip force is adjusted in anticipation of the mechanical consequences of hand motion (i.e., load force) to prevent the object from slipping. This predictive behavior is assumed to rely on an internal representation of the object dynamic properties, which would be elaborated via visual information ...
Boisgontier M - - 2010
The purpose of this study was to assess maximal grip force in two conditions of voluntary muscular contraction (MVC) and electrical stimulation superimposed on voluntary muscular contraction (SES) to better understand mechanisms and effectiveness of electrical stimulation of the hand. There is conflicting evidence regarding the effectiveness of electrical stimulation ...
Acharya Soumyadipta - - 2010
Four human subjects undergoing subdural electrocorticography for epilepsy surgery engaged in a range of finger and hand movements. We observed that the amplitudes of the low-pass filtered electrocorticogram (ECoG), also known as the local motor potential (LMP), over specific peri-Rolandic electrodes were correlated (p < 0.001) with the position of ...
Lin Jia-Hua - - 2010
Powered hand tools have the potential to produce reaction forces that may be associated with upper extremity musculoskeletal disorders. This study examined and compared the kinetic and physiological impacts on operator upper extremities between the fastening and unfastening operations. Thirty-two healthy, right-handed male operators used four tools on two joint ...
Chappell P H - - 2010
The primary objective of the experiments was to investigate the wrist motion of a person while they were carrying out a prehensile task from a clinical hand function test. A six-camera movement system was used to observe the wrist motion of 10 participants. A very light sphere and a heavy ...
Tung Wen-Lin - - 2010
BACKGROUND: Clinical diagnosis and classification of trigger fingers is traditionally based on physical examinations and certain obvious symptoms. However, it might lack quantitative evidence to describe the different graded trigger digits. This study provides quantitative evidence of kinematics and functional differences among different graded trigger fingers based on Froimson's classification. ...
Hosono Noboru - - 2010
STUDY DESIGN: Motion analysis on video files that captured grip and release cycles with fingers. OBJECTIVE: To reveal the kinematic characteristics of finger motion in cervical myelopathy. SUMMARY OF BACKGROUND DATA: Myelopathy patients are often unable to smoothly move their fingers in grip and release cycles. Although paradoxical wrist motion ...
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