In this paper we report for the first time the design, fabrication and characterization of an optically transparent electrode array for micro-electrocorticography. We present a 49-channel ECoG array with an electrode ...
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作者：
K.Jimmy HsiaRashid BashirKidong ParkLarry MilletHuan LiNamjung KimXiaozhong JinGabriel PopescuN.R.AluruDepartment of Mechanical Science & Engineering
Department of BioengineeringMicro and Nanotechnology LaboratoryUniversity of IllinoisUrbanaIL 61801USA Department of BioengineeringMicro and Nanotechnology LaboratoryDepartment of Electrical and Computer Engineering5Beckman Institute of Advanced Science and TechnologyUniversity of IllinoisUrbanaIL 61801USA Department of Electrical and Computer EngineeringUniversity of IllinoisUrbanaIL 61801USA Department of Mechanical Science & EngineeringUniversity of IllinoisUrbanaIL 61801USA Department of Electrical and Computer EngineeringBeckman Institute of Advanced Science and TechnologyUniversity of IllinoisUrbanaIL 61801USA Department of Mechanical Science & EngineeringMicro and Nanotechnology LaboratoryBeckman Institute of Advanced Science and TechnologyUniversity of IllinoisUrbanaIL 61801USAUniversity of IllinoisUrbanaIL 61801USA
To investigate the neural activity corresponding to different cognitive states, it is of great importance to localize the cortical areas that are associated with task-related modulation. In this paper, we propose a no...
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ISBN:
(纸本)9781424441211
To investigate the neural activity corresponding to different cognitive states, it is of great importance to localize the cortical areas that are associated with task-related modulation. In this paper, we propose a novel discriminant pattern source localization (DPSL) method to analyze MEG data. Unlike most traditional source localization methods that aim to find "dominant" sources, DPSL is developed to capture the "differential" sources that distinguish different cognitive states. As will be demonstrated by the experimental results in this paper, the proposed DPSL method offers superior accuracy to identify the spatial locations of task-related sources.
In this paper, we present the results of continuous monitoring metabolic sensor arrays capable of monitoring changes in glucose, ionic strength and pH in the surrounding analyte continuously. Piezoresistive pressure s...
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In this paper, we present the results of continuous monitoring metabolic sensor arrays capable of monitoring changes in glucose, ionic strength and pH in the surrounding analyte continuously. Piezoresistive pressure sensors containing KOH etched cavities and pressure sensing membranes with and without perforations were fabricated in different sizes (1.5×1.5 mm2, 1.25×1.25 mm2, 1×1 mm2 and 0.5×0.5 mm2) to account for the sensitivities of the different types of hydrogels that were investigated. Figure 1 shows the schematic and the image of the sensors. Stimuli responsive hydrogels were used as the sensing elements to detect glucose and ionic strength in phosphate buffered saline at pH 7.4 and at room temperature. Response times of ∼10 and ∼6 minutes during swelling cycle and ∼5 and ∼4 minutes for the shrinking cycle were measured for glucose and ionic strength responsive hydrogels respectively.
To explore the effect of the location of a visual stimulus on neural responses in the primary visual cortex （V1）, a micro-electromechanical system-based microelectrode array with nine channels was implanted on the c...
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To explore the effect of the location of a visual stimulus on neural responses in the primary visual cortex （V1）, a micro-electromechanical system-based microelectrode array with nine channels was implanted on the cerebral dura mater of V1 in adult cats. 2 Hz pattern reversal checkerboard stimul were used to stimulate the four visual quadrants （i.e., upper left, upper right, lower left, and lower right fields）. The results showed that there was a N75 component of the visual evoked potential around 50-80 ms after the onset of a checkerboard stimulus, and the onset of these N75 peaks varied with different stimulus locations. The checkerboard stimuli Jnduced shorter latencJes in the contralateral V1 than in the ipsilateral V1, while the checkerboard stimulus in the upper half visual field induced shorter latencies for N75. These results suggested that the pattern-reversal stimuli induced neural activities in V1 that can be recorded with multichannel microelectrodes, and more detailed temporal and spatial properties can be measured.
We demonstrate the resonance wavelength and quality factor dependence of 50nm defect-hole placement within photonic crystal L3 microcavities. Proper placement of defect-holes leads to a 12% increase in photonic crysta...
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Control over the 1.5 µm emission from erbium is desirable for communication and computational technologies because the erbium emission falls in the window of maximum transmission for silica based fiber optics. Tu...
Control over the 1.5 µm emission from erbium is desirable for communication and computational technologies because the erbium emission falls in the window of maximum transmission for silica based fiber optics. Tunable, narrow, directional, and enhanced erbium emission from silicon based 1-D photonic bandgap structures will be demonstrated. The structures are prepared by anodic etching of crystalline silicon and consist of two highly reflecting Bragg reflectors sandwiching an active layer. The cavities are doped by electro-migrating the erbium ions into the porous silicon matrix, followed by high temperature oxidation. By controlling the oxidation temperature, porosity, and thickness of the structure, the position of the erbium emission is tuned to emit in regions where the normal erbium emission is very weak. The erbium emission from the cavity is narrowed to a full width at half maximum (FWHM) of 12 nm with a cavity quality factor Q of 130, highly directional with a 20 degree emission cone around the normal axis, and enhanced by more than one order of magnitude when compared to its lateral emission. Erbium photoluminescence (PL) from porous silicon 2-D photonic bandgap structures is also demonstrated.
The effect of back biasing on the performance of a planar tunnel field-effect transistor (TFET) implemented on a silicon-on-insulator substrate is investigated. It is found that reverse back biasing reduces the subthr...
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The effect of back biasing on the performance of a planar tunnel field-effect transistor (TFET) implemented on a silicon-on-insulator substrate is investigated. It is found that reverse back biasing reduces the subthreshold swing SS and increases the range of drain current over which SS is less than ( k B T / q ) ln (10); hence, it is effective for improving the TFET on/off current ratio for low operating voltages (≤ 0.5 V).
Step-graded InGaPySb1-y and InxGa 1-xAs metamorphic buffer layer (MBL) structures are grown on GaAs substrates by metal-organic chemical vapor deposition (MOCVD). AFM analysis indicates that graded group V InGaPySb1-y...
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