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Results 201 - 250 of 937
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Kamoun Saber - - 2010
The inscription of light-induced self-written waveguides (LISW) with multimode optical fibers cannot be achieved by using coherent light because of the filamentation phenomena coming from the interferences among the different propagating modes. To suppress this filamentation, we have used two distinct strategies, an incoherent light writing technique and an "on ...
Feng Bin - - 2010
Information about colorectal distension (i.e., colorectal dilation by increased intraluminal pressure) is primarily encoded by stretch-sensitive colorectal afferents in the pelvic nerve (PN). Despite anatomic differences between rectum and distal colon, little is known about the functional roles of colonic vs. rectal afferents in the PN pathway or the quantitative ...
Ming Zhang - - 2010
During electrocochleography, that is, ECochG or ECoG, a recording electrode can be placed in the ear canal lateral to the tympanic membrane. We designed a concha electrode to record both sinusoidal waveforms of cochlear microphonics (CMs) and auditory brainstem responses (ABRs). The amplitudes of CM waveforms and Wave I or ...
Kudlinski A - - 2009
GeO(2)-doped-core photonic crystal fibers show greatly enhanced Kerr and Raman responses with respect to pure silica without any significant modification of the group-velocity dispersion curve. We show that such fibers allow a significant improvement of cw-pumped supercontinuum generation. We report for the first time to our knowledge the generation of ...
Mouret Gaël - - 2009
A frequency doubled erbium doped modelocked fiber frequency comb is used to implement a THz photomixing synthesizer. The useful THz linewidth is in order of 150 kHz and has been assessed along with the frequency accuracy by spectroscopic measurements demonstrating a relative accuracy of 10(-8) at frequencies around 1 THz. ...
Qian Kai - - 2009
We proposed and experimentally demonstrated an extremely simple and feasible slow-light technique to achieve tunable optical delay by using the Er/Yb codoped fiber Bragg grating (FBG). The signal light experiences strong dispersion when it is launched into the reflection edge of FBG, and the group delay value is determined by ...
Chang Ching-Hung - - 2009
A full-duplex fiber-to-the-X (FTTX)/radio-over-fiber (ROF) transport system based on a broadband amplified spontaneous emission (ASE) light source is proposed and demonstrated for rural wide-spread villages. Combining the concepts of long-transmission transmission and ring topology, a long-haul single-mode fiber (SMF) trunk is sharing with multiple rural villages. Externally modulated baseband (BB) ...
Temchin Andrei N AN Hugh Knowles Center (Department of Communication Sciences and Disorders), Northwestern University, 2240 Campus Drive, Evanston, IL 60208-3550, - - 2010
Responses to tones with frequency < or = 5 kHz were recorded from auditory nerve fibers (ANFs) of anesthetized chinchillas. With increasing stimulus level, discharge rate-frequency functions shift toward higher and lower frequencies, respectively, for ANFs with characteristic frequencies (CFs) lower and higher than approximately 0.9 kHz. With increasing frequency ...
Ghosh Aditi - - 2009
The gain and noise characteristics of a fiber Brillouin amplifier are studied experimentally and analyzed using a dispersion shifted fiber. Based on these measurements, the optimal conditions of gain and on-off ratio are identified for slow light generation.
Yilmaz Ugur - - 2010
OBJECTIVES: To compare sensory thresholds in different nerve-fiber types in men with chronic pelvic pain syndrome (CPPS) and healthy controls, using thermal sensory testing and measuring current perception thresholds (CPT). METHODS: We enrolled 22 men with CPPS and 20 healthy control participants. We determined the thermal sensory perception thresholds of ...
Abedin Kazi S - - 2009
We report broadening in spectrum as light is backreflected from a propagating fiber fuse. The formation of micrometer-size voids results in periodic changes in Fresnel reflection occurring in the leading part of the fuse. High-resolution measurement of the optical spectrum via heterodyne detection revealed an upshift (Doppler shift) in the ...
Aref S H - - 2009
In this work, sensitivity to strain and temperature of a sensor relying on modal interferometry in hollow-core photonic crystal fibers is studied. The sensing structure is simply a piece of hollow-core fiber connected in both ends to standard single mode fiber. An interference pattern that is associated to the interference ...
Sencimen Metin - - 2009
To examine histological aspects of the ligaments between the middle ear and temporomandibular joint and suppose a theoretical role of their structural characteristics on mobility of mallear ossicle. The ligaments were obtained by microdissection of middle cranial fossa on both sites of 15 cadavers fixed in formalin solution and were ...
Beraudi Alina - - 2010
Pattern of osteonal classification referred to collagen fiber orientation in a human fibula was studied. Along the length of the whole bone, serial 100-microm parallel cross sections were obtained and analyzed by circularly polarized light microscopy. The distribution of 3 different kinds of osteons (transversal, alternated and longitudinal-hooped) depending on ...
Preussler Stefan - - 2009
We show a method for distortion-free quasi storage of light which is based on the coherence between the spectrum and the time representation of pulse sequences. The whole system can be considered as a black box that stores the light until it will be extracted. In the experiment we delayed ...
Madl A K - - 2009
Asbestos-containing brake linings were used in heavy-duty construction equipment such as tractors, backhoes, and bulldozers prior to the 1980s. While several published studies have evaluated exposures to mechanics during brake repair work, most have focused on automobiles and light trucks, not on heavy agricultural or construction vehicles. The purpose of ...
Yan Min - - 2009
Infrared (IR) light is considered important for short-range wireless communication, thermal sensing, spectroscopy, material processing, medical surgery, astronomy etc. However, IR light is in general much harder to transport than optical light or microwave radiation. Existing hollow-core IR waveguides usually use a layer of metallic coating on the inner wall ...
Kim Yunseok - - 2009
A low-noise fiber frequency comb is demonstrated to improve the frequency accuracy and linewidth by suppressing the phase noise caused by the nonlinear self-phase modulation as well as the amplified spontaneous emission within the Er-doped fiber amplifier. The linewidth of the carrier-envelop- offset signal measures less than 1.9 mHz and ...
Lee Won-Soo - - 2009
Photoaggravation of hair aging includes various chemical and physical changes in fiber properties which lead to an increase in fiber porosity, loss of mechanical strength and an increase in surface roughness. These changes come from lipid oxidation, disulfide bond cleavage, tryptophan degradation and cysteic acid formation. Hair exposed to sunlight ...
Johansson Johannes D - - 2009
An electrode with adjacent optical fibers for measurements during navigation and radio frequency lesioning in the brain is modeled for Monte Carlo simulations of light transport in brain tissue. Relative reflected light intensity at 780 nm, I780, from this electrode and probes with identical fiber configuration are simulated using the ...
Pu Sean - - 2009
We have successfully demonstrated cavity ring-down spectroscopy in a fiber ring with a long-period grating cavity. The cavity couples >99% of light from core to cladding, interacts with the environment surrounding the fiber, and then couples unabsorbed light back into the fiber core. This design provides a relatively large evanescent ...
Blake Charles L - - 2009
Asbestos containing materials are a component of many vehicle brake systems, including those found in some light aircraft. To characterize the asbestos exposure that results from the installation and maintenance of these components, an aircraft fitted with asbestos containing brake pads had brake changes performed while both area and personal ...
Heinz Michael G MG Department of Speech, Language, and Hearing Sciences, Purdue University, West Lafayette, IN 47907, USA. - - 2009
Any sound can be separated mathematically into a slowly varying envelope and rapidly varying fine-structure component. This property has motivated numerous perceptual studies to understand the relative importance of each component for speech and music perception. Specialized acoustic stimuli, such as auditory chimaeras with the envelope of one sound and ...
Abedin Kazi S - - 2009
The properties of backreflected light due to voids in a fiber fuse were studied using optical coherence-domain reflectometry of a damaged fiber and real-time monitoring of the electrical (RF) and optical frequency spectrum. Light reflected backward at the interface of a propagating fiber fuse acquired low-frequency broadband amplitude modulation, which ...
Yu Jianhui - - 2009
We demonstrate a very simple all-optical switch (AOS) based on the bend effect of a nm fiber taper driven by outgoing light. The AOS operates at relative low control power compared with those of using nonlinear effect. In our configuration, we find that the turnoff and turnon time of the ...
Müller W E G - - 2009
Two classes of sponges (animal phylum Porifera) possess a siliceous skeleton which is composed of spicules. Studying the optical fiber-mechanical properties of large spicules from hexactinellid sponges (> 5 cm) it was demonstrated that they are effective light-collecting optical fibers. Here, we report that the demosponge Suberites domuncula is provided ...
Guan Yafeng - - 2009
Photomultiplier tubes (PMT) are widely used for the weak light detection in some types of biosensors. A light detection system for biosensors based on PMT generally contains optic fibers, PMT, and filters. Basic principles of those accessories were provided in this chapter. The guides to selecting fibers, filters, PMT, and ...
Lesniak Daine R DR Department of Systems and Information Engineering, University of Virginia, Charlottesville, VA 22904, - - 2009
The slowly-adapting type I mechanoreceptor (SA-I) exhibits variability in its steady-state firing rate both within an afferent upon repeated stimulation and between afferents. Additionally, inter-spike intervals of the SA-I are extremely variable during this steady-state firing. While variability of the SA-I response has been noted previously, the work presented herein ...
Sims David W - - 2009
Satellite tracking of large pelagic fish provides insights on free-ranging behaviour, distributions and population structuring. Up to now, such fish have been tracked remotely using two principal methods: direct positioning of transmitters by Argos polar-orbiting satellites, and satellite relay of tag-derived light-level data for post hoc track reconstruction. Error fields ...
Palmer Alan R AR MRC Institute of Hearing Research, University Park, Nottingham NG7 2RD, UK. - - 2009
The directionality of hair cell stimulation combined with the vibration of the basilar membrane causes the auditory nerve fiber action potentials, in response to low-frequency stimuli, to occur at a particular phase of the stimulus waveform. Because direct mechanical measurements at the cochlear apex are difficult, such phase locking has ...
Mogdans Joachim - - 2009
We investigated how fibers in the anterior lateral line nerve of goldfish, Carassius auratus, respond to water motions generated by an object that was moved alongside the fish. Motion direction was from anterior to posterior or opposite, object diameter was between 0.1 and 4 cm and the distance between object ...
Lysakowski Anna A Department of Anatomy and Cell Biology, University of Illinois at Chicago, Illinois 60612, USA. - - 2008
Type I hair cells outnumber type II hair cells (HCs) in squirrel monkey (Saimiri sciureus) cristae by a nearly 3:1 ratio. Associated with this type I HC preponderance, calyx fibers make up a much larger fraction of the afferent innervation than in rodents (Fernández et al. [1995] J. Neurophysiol. 73:1253-1269). ...
Quinn Kyle P - - 2008
Detecting the initiation of mechanical injury to biological tissue, and not just its ultimate failure, is critical to a sensitive and specific characterization of tissue tolerance, development of quantitative relationships between macro- and microstructural tissue responses, and appropriate interpretation of physiological responses to loading. We have developed a novel methodological ...
Jaw F-S - - 2009
The somatotopic map of the first nociceptive component in the primary somatosensory cortex (S1) is still unclear. In this study, a CO(2) laser was applied to the tail of the rat to induce nociception without the interference from large myelinated (A(beta)) fibers. Thus, only noxious fibers could be activated. Two-dimensional ...
Stuart Kate - - 2008
The ability to alter collagen organization could lead to more physiologically relevant scaffolds for tissue engineering. This study examined collagen organization in the presence of polysaccharide and the resulting effects on viscoelastic properties. Fibrillogenesis in the presence of chondroitin sulfate (CS) resulted in changes in the collagen network organization with ...
Gauvreau B - - 2008
We present the fabrication and use of plastic Photonic Band Gap Bragg fibers in photonic textiles for applications in interactive cloths, sensing fabrics, signage and art. In their cross section Bragg fibers feature periodic sequence of layers of two distinct plastics. Under ambient illumination the fibers appear colored due to ...
Milenkovic Nevena - - 2008
Here we have systematically characterized the stimulus response properties of mechanosensitive sensory fibers in the mouse saphenous nerve. We tested mechanoreceptors and nociceptors with defined displacement stimuli of varying amplitude and velocity. For each sensory afferent investigated we measured the mechanical latency, which is the delay between the onset of ...
Gilbert Thomas W TW McGowan Institute for Regenerative Medicine, Department of Surgery, University of Pittsburgh, Pittsburgh, PA 15219, - - 2008
The collagen fiber alignment and biomechanical behavior of naturally occurring extracellular matrix (ECM) scaffolds are important considerations for the design of medical devices from these materials. Both should be considered in order to produce a device to meet tissue specific mechanical requirements (e.g., tendon vs. urinary bladder), and could ultimately ...
Kvavle Joshua M - - 2008
Elliptical core D-fiber is difficult to fusion splice to other types of fiber due to its small core and D-shaped cladding. The presented method of splicing D-fiber to PANDA fiber involves using E-fiber in a bridge splice. The E-fiber core is expanded to match the mode of the PANDA fiber. ...
Temchin Andrei N - - 2008
Spontaneous activity and frequency threshold tuning curves were studied in thousands of auditory nerve fibers in chinchilla. The frequency distribution of spontaneous activity rates is strongly bimodal for auditory nerve fibers with characteristic frequency <3 kHz but only mildly bimodal for the entire sample. Spontaneous activity rates and thresholds at ...
Rothmaier Markus - - 2008
Biomedical sensors, integrated into textiles would enable monitoring of many vitally important physiological parameters during our daily life. In this paper we demonstrate the design and performance of a textile based pulse oximeter, operating on the forefinger tip in transmission mode. The sensors consisted of plastic optical fibers integrated into ...
Temchin Andrei N - - 2008
Frequency-threshold tuning curves were recorded in thousands of auditory-nerve fibers (ANFs) in chinchilla. Synthetic tuning curves with 21 characteristic frequencies (187 Hz to 19.04 kHz, spaced every 1/3 octave) were constructed by averaging individual tuning curves within 2/3-octave frequency bands. Tuning curves undergo a gradual transition in symmetry at characteristic ...
Woody Shane - - 2008
A single standing wave sensor was investigated and experiments demonstrated release capability of glass microscale objects. It is shown that this micrometer scale fiber may be employed as miniaturized tweezers able to pick up specimens and routinely release them when the standing wave is energized. Furthermore, it is demonstrated that ...
Langille Matthew - - 2008
This study examines the ability to selectively activate different nerve fibers in a finger by using different sinusoidal stimulation frequencies. Specifically, the stimulation of A-beta, A-delta, and C-fibers is looked into, and responses from each of three different stimuli (5 Hz, 250 Hz, and 2000 Hz) are compared. Action potential ...
Wang Yuntao - - 2008
Specklegram in multimode fiber has successfully been used as a sensor for detecting mechanical disturbance. Speckles in a multimode pure silica grapefruit fiber are observed and compared to that of a step-index multimode fiber, showing different features between them. The sensitivities to external disturbance of two kinds of fiber were ...
Chuang Kuo-Chih - - 2008
A method for setting up a fiber Bragg grating (FBG) sensor which can measure the pointwise, out-of-plane or in-plane dynamic displacement is proposed. The proposed FBG sensor is reusable. A multiplexing demodulation system based on a single long-period fiber grating is used in this study. The experimental results of the ...
Wei Zhensong - - 2008
Numerical simulations that incorporate a biochemomechanical model for the contractility of the cytoskeleton have been used to rationalize the following observations. Uniaxial cyclic stretching of cells causes stress fibers to align perpendicular to the stretch direction, with degree of alignment dependent on the stretch strain magnitude, as well as the ...
Majumdar Ayan - - 2008
The fabrication, implementation, and evaluation of an in-fiber white-light interferometric distance sensor that is capable of measuring the absolute value of an arbitrary small distance are presented. Taking advantage of the mode-coupling effect of a long-period fiber grating, an additional cavity distance is added to the optical path difference of ...
Cao Zhaoliang - - 2008
To correct horizontal turbulences, a nematic liquid crystal wavefront corrector (NLC WFC) with a fast response is used. It can linearly modulate 2pi radian at a wavelength of 633 nm. The closed-loop frequency of the adaptive optics system was originally only 12 Hz. Hence, a control system using the NLC ...
Houde Robert A - - 2008
The auditory periphery is well represented as a bank of band pass filterinner hair cell (IHC) channels, with each IHC providing half wave rectification, amplitude compression, and conversion to firing probability on the auditory nerve (AN) fibers innervating that IHC. Frequency resolution varies dramatically with sound intensity, ranging from sharp ...
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