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CreatorTitleDescriptionSubjectDate
1 Macleod, Robert S.Sensitivity and specificity of substrate mapping: An in silico framework for the evaluation of electroanatomical substrate mapping strategiesBackground - Voltage mapping is an important tool for characterizing proarrhythmic electrophysiological substrate, yet it is subject to geometric factors that influence bipolar amplitudes and thus compromise performance. The aim of this study was to characterize the impact of catheter orientation on...2014-01-01
2 Christensen, Douglas A.Ultrasound beam simulations in inhomogeneous tissue geometries using the hybrid angular spectrum methodThe angular spectrum method is a fast, accurate and computationally efficient method for modeling wave propagation. However, the traditional angular spectrum method assumes that the region of propagation has homogenous properties. In this paper, the angular spectrum method is extended to calculate u...2012-01-01
3 Jenson, Justin Michael; Bock, Susan C.Mitigating spinal cord injuryHow would your life change if you became one of the 15,000 Americans to suffer a spinal cord injury this year? Trauma to the spinal cord causes immediate loss of function below the level of the injury. Then, in the hours and days after the accident, the body's secondary injury response may extend ...Trapeze Interactive Poster2010-03-15
4 Collins, Zachary J.; Poelzing, StevenCharacterization of a four-camera ratiometric optical mapping systemElectrical activity precedes calcium mediated heart contractions. Optical mapping takes advantage of minimally invasive fluorescent molecular probes to image both electrical and calcium activity. These molecular probes allow for ratiometric imaging. We characterize a four camera system capable of...Optical mapping; Ratiometric imaging; Di-4-ANEPPS; Indo-1; Trapeze Interactive Poster2010-03-15
5 Gesteland, Raymond F.; Krapcho, Karen J.; Talbot, Phil; Thulin, CraigCrystallization of the MS2 translational repressor alone and complexed to bromouridineThe coat protein from the MS2 bacteriophage plays a dual role by encapsidating viral RNA and also by binding RNA as a translational repressor. In order to study the isolated dimer in a conformation not influenced by capsid interactions, a mutant molecule was crystallized that is defective in capsid ...Crystallization; RNA Bacteriophage; RNA Hairpin; Translational Repressor1995
6 Horch, Kenneth W.; Tuckett, Robert P.; Burgess, Paul RichardNeural signal for the intensity of a tactile stimulusThe effect of indenting the skin at different rates on the perceived intensity of the stimulus was studied by indenting the skin of the fingertip with two triangular waveforms, given as a pair. The subjects were asked to judge which member of the pair was more intense. Perceived intensity was foun...Skin; Indentation; Nerve impulses1984
7 Gesteland, Raymond F.Characterization of lysozyme messenger and lysozyme synthesized in vitroIn vitro systems for protein systhesis have been in wide use for about 10 years. In most of the early work protein synthesis was measured by following the incorporation of radioactive amino acids into acid precipitable material. This test cannot distinguish between the synthesis of complete, activ...Lysozyme Messenger; Lysozyme Synthesized; Protein Synthesis1969
8 Horch, Kenneth W.Perspectives on new electrode technology for stimulating peripheral nerves with implantable motor prosthesesAbstract-The limits of present electrode technology are being reached in current motor prostheses for restoring functional movement in paralyzed people. Improved devices require electrodes and stimulation methods that will activate muscles selectively and independently with less implanted hardwa...Paralysis; Prostheses; Electrodes1995
9 Horch, Kenneth W.; Normann, Richard A.Simulation of a phosphene field based visual prosthesisA visual prosthesis for the blind based upon electrical stimulation of the visual cortex requires the development of an array of electrodes. To establish design specifications for such an electrode array, we have conducted psychophysical experiments with normally sighted subjects wearing a portable...Visual prosthesis; Phosphene simulator1990
10 Horch, Kenneth W.Stability of chronic intrafascicular electrode recordingsWe have implanted intrafascicular electrodes in peripheral nerves of cats and have recorded neural activity from a small population of nerve fibers for as long as six months, suggesting that these electrodes can be used on a chronic basis to acquire information about limb position, muscle force and ...Intrafascicular electrodes; Electrode recordings1989
11 Horch, Kenneth W.Information contrained in sensory nerve recordings made with intrafascicular electrodesMultiunit recordings were made in anesthetized cats with chronically implanted intrafascicular electrodes over a period of six months. Neural signals recorded with these electrodes consisted of activity in sensory fibers innervating a variety of cutaneous mechanoreceptors. Mechanical stimuli wer...Intrafascicular electrodes; Functional electrical stimulation (FES); Closed-loop control1991
12 Gesteland, Raymond F.Translation of Rl7 RNA fragmentsExamination of the events during infection of cells by RNA phages reveals phemonomena that are surprisingly complex for a virus that has only enough information to code for three to four proteins. The coat protein is synthesized at a rapid rate through most of the infectious cycle making it the pre...Electrophoresis; RNA, Messenger; Peptide Biosynthesis; Kinetics1969
13 Normann, Richard A.; Kolb, Helga; Lasater, Eric M.Signal integration at the pedicle of turtle cone photoreceptors: an anatomical and electrophysiological studyThe morphology of the axon which connects the cell body and pedicle of turtle cone photoreceptors was studied by light and electron microscopy. The axon which contains numerous synaptic vesicles, some endoplasmic reticulum, and a few cisternae is basically filled with cytoplasm. The length of the ax...Cone Photoreceptor, Voltage Clamp; Isolated Cells; Input Resistance; Cell Body-Pedicle Coupling1989
14 Horch, Kenneth W.Separation of action potentials in multiunit intrafascicular recordingsClassification of action potentials in multiunit recordings was based on the use of various types of features to uniquely characterize action potentials from different cells. We compared classification results obtained using three types of descriptive features: digitized data points, amplitude and ...Long-term implantable intrafascicular electrodes; Nerve recordings; Simulated neural data1992
15 Christensen, Douglas A.; Horch, Kenneth W.Accelerated dual-degree BS/MS program - experience with the first three yearsWe have initiated a pilot program that accelerates the studies of a small group of highly qualified students early in their college careers and allows them to earn both a bachelor's degree and a master's degree in about four years after starting college. It does this by introducing them early to res...Accelerated dual-degree program2004
16 Christensen, Douglas A.Influence of temperature probe sheathing materials during ultrasonic heatingThe influence of sheathing materials upon temperature probes used during the monitoring of ultrasonic heating was measured. The measurements show that the sheathing can be heated in a manner not representative of the temperature rise occurring in the surrounding material, altering the probe reading...Ultrasonic hyperthermia; Sheathing; Phantom tests; Teflon1986-05
17 Gesteland, Raymond F.Cell-free synthesis of herpes simplex virus proteinsPolyribosomes isolated from herpes simplex virus type I (HSV-1)-infected cells have been used to program a eucaryotic cell-free translation system. At least 10 HSV-specific polypeptides, with apparent molecular weights of 25,000 to 160,000, are synthesized by wild-type HSV-infected polyribosomes. Po...Viral Proteins; Herpes Simplex; Peptide Biosynthesis; Thymidine Kinase1977
18 Christensen, Douglas A.FDTD modeling in the design of optical chemical sensor structuresThe finite-difference time-domain method (FDTD) is a numerical technique for solving Maxwell's equations in a discretized space and time frame. It has been used extensively in the analysis of electrically large structures in the microwave domain, but has only recently been applied to optical proble...Finite-difference time-domain method; Immunochemical fluorosensors; Planar waveguides1991
19 Gesteland, Raymond F.; Atkins, John F.; Tuohy, Therese M.Uninterrupted translation through putative 12-nucleotide coding gap in sequence of carA: business as usualPrevious work of others reported an untranslated stretch of 12 nucleotides in the 5' coding sequence of carA from Pseudomonas aeruginosa. However, N-terminal protein sequencing of carA-lacZ translational fusions shows that these 12 nucleotides are normally translated in a continuous triplet manner, ...Base Sequence; Protein Biosynthesis; Sequence Deletion1994
20 Horch, Kenneth W.Selective activation of functional muscle groups through stimulation of spinal motor poolsA microelectrode was used to stimulate motor neurons in the lumbo-sacral spinal cord of adult cats. Consistent with spinal cord anatomical studies, we found that the motor neurons responsible for activation of individual muscle groups are situated together in specific areas of the cord, forming mot...Spinal motor pools1993
21 Horch, Kenneth W.; Dhillon, Gurpreet S.Direct neural sensory feedback and control of a prosthetic armEvidence indicates that user acceptance of modern artificial limbs by amputees would be significantly enhanced by a system that provides appropriate, graded, distally referred sensations of touch and joint movement, and that the functionality of limb prostheses would be improved by a more natural co...Peripheral Nerve Implant; Prosthetic Limb Control; Sensory Feedback2005-12
22 Horch, Kenneth W.Unit analysis in composite neural recordingsWe have used threshold level, sinusoidal stimuli to selectively elicit phase-locked activity from cutaneous mechanoreceptors, for the purpose of evaluating single unit activity in multi-unit peripheral nerve recordings. Each receptor is characterized by its response to a range of mechanical stimuli ...Neural recordings; Nerve fibers; Cutaneous mechanoreceptors1989
23 Horch, Kenneth W.Towards a neuroprosthetic armEvidence indicates that user acceptance of modern artificial limbs by amputees would be significantly enhanced by a system that provides appropriate, graded, distally referred sensations of touch and joint movement, and that the functionality of limb prostheses would be improved by a more natural co...Neuroprosthetic arm; Peripheral nerve; Neuroprosthetics; Amputee2006
24 Christensen, Douglas A.Modeling sources in the FDTD formulation and their use in quantifying source and boundary condition errorsThe modeling of voltage and current sources as either added or replaced sources in FDTD simulations is described and their differences discussed in terms of a transmission line analogy. An infinitesimal current element (ICE) is used to illustrate the validation of added source modeling and to study...Finite-difference time-domain method; Infinitesimal current element1995-04
25 Normann, Richard A.; Clark, Gregory A.; McDonnall, DanielSelective motor unit recruitment via intrafascicular multielectrode stimulationRecruitment of force via independent asynchronous firing of large numbers of motor units produces the grace and endurance of physiological motion. We have investigated the possibility of reproducing this physiological recruitment strategy by determining the selectivity of access to large numbers of ...Funtional Neuromuscular Stimulation; Microelectrode Array; Neuroprosthesis; Intrafascicular Multielectrode Stimulation; Cats2004
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