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26 Normann, Richard A.; Campbell, Patrick K.; Jones, Kelly E.; Huber, Robert J.; Horch, Kenneth W.Silicon-based, three-dimensional neural interface: manufacturing processes for an intracortical electrode arrayA method has been developed for the manufacture of a "three-dimensional" electrode array geometry for chronic intracortical stimulation. This silicon based array consists of a 4.2 x 4.2 x 0.12 mm thick monocrystalline substrate, from which project 100 conductive, silicon needles sharpened to facilit...Electric Stimulation; Electrodes, Implanted; Sensory Cortex; Intracortical Electrode Array1991
27 Horch, Kenneth W.On the number and nature of regenerating myelinated axons after lesions of cutaneous nerves in the cat1. Electrophysiological and anatomical techniques were used to investigate normal and regenerating sural and posterior femoral cutaneous nerve fibres in the cat. 2. One and a half years after transection of these nerves it was found that the regenerating neurones supported multiple sprouts in the...Nerve fibres; Transection; Nerve injury1981
28 Vardhan, AvantikaCharacterizing growth patterns in longitudinal MRI using image contrastUnderstanding the growth patterns of the early brain is crucial to the study of neuro-development. In the early stages of brain growth, a rapid sequence of biophysical and chemical processes take place. A crucial component of these processes, known as myelination, consists of the formation of a myel...2014-01-01
29 Horch, Kenneth W.Tracking changes in action potential shapes in chronic multi-unit intrafascicular recordings using neural network pattern recognition techniquesA novel scheme is proposed to train an Artificial Neural Network (A") classifier, on a repeated basis, in order to track temporal changes in the shapes of the action potentials recorded through chronically implanted intrafascicular electrodes. This scheme uses classification results of the ANN Clas...Intrafascicular electrodes; Artificial neural network1994
30 Christensen, Douglas A.Effects of increased energy prices on U.S. agriculture: an econometric approachAlthough the contents of this manuscript remain the responsibility of the authors, we wish to thanks a group of reviewers for the time and conscientious effort they put forth to solidify this final draft. Andrew Morton, Brian Holding, Wesley Buchele, and Arnold Paulsen deserve much credit for their ...Energy prices1981
31 Horch, Kenneth W.Control of ankle position using neural feedbackThis paper describes a closed loop control system that uses afferent neural activity from muscle spindle fibers as feedback for controlling ankle position. The gastrocnemius muscle was stimulated through a dual channel intrafascicular electrode implanted in a fascicle of the tibial nerve. Dual cha...Neuromuscular stimulation; Peripheral nerve; Joint angle1994
32 Gesteland, Raymond F.; Atkins, John F.Evolutionary specialization of recoding: frameshifting in the expression of S. cerevisiae antizyme mRNA is via an atypical antizyme shift site but is still +1An autoregulatory translational shift to the +1 frame is required for the expression of ornithine decarboxylase antizyme from fungi to mammals. In most eukaryotes, including all vertebrates and a majority of the studied fungi/yeast, the site on antizyme mRNA where the shift occurs is UCC-UGA. The me...Antizyme; ODC; Polyamines; Frameshifting2006
33 Normann, Richard A.Effects of GABA and related drugs on horizontal cells in the isolated turtle retinaThe role of GABA in the outer plexiform layer of the turtle retina has been examined by intracellular recordings from L- and C-type horizontal cells in the isolated retina preparation. GABA (1-5 mM) slightly depolarized the L-type horizontal cells, reduced the amplitude of their photoresponses, and ...Retina; Horizontal Cells; Synapse; Negative Feedback; GABA; Turtle1990
34 Horch, Kenneth W.Mechanical testing of metallic and polymeric intrafascicular electrodesWe are exploring alternatives to Pt/Ir wire for constructing ultra-flexible neural intrafascicular electrodes suitable for chronic implantation. In this study we measured the flexural properties of several kinds of fine metal wires and conducting polymer fibers. The fibers were made either of in...Intrafascicular electrodes; Polymer fibers1994
35 Gesteland, Raymond F.; Atkins, John F.; Baranov, Pavel V.P-site tRNA is a crucial initiator of ribosomal frameshiftingThe expression of some genes requires a high proportion of ribosomes to shift at a specific site into one of the two alternative frames. This utilized frameshifting provides a unique tool for studying reading frame control. Peptidyl-tRNA slippage has been invoked to explain many cases of programmed ...Translation; Recoding; Kinetic Model; Frameshifting; Ribosome2004
36 Christensen, Douglas A.; Herron, James N.Comparison of robust coupling techniques for planar waveguide immunosensorsWe have analyzed and fabricated two different coupling schemes to meet the requirements for a convenient means of coupling into a planar waveguide immunosensor that is relatively insensitive to beam alignment. These are the "launch" coupler and the grating coupler. Each possesses advantages and dis...Planar waveguide immunosensors; Fluorescence; Launch coupler; Grating coupler1993
37 Horch, Kenneth W.Differential activation of nerve fibers with magnetic stimulation in humansEarlier observations in our lab had indicated that large, time-varying magnetic fields could elicit action potentials that travel in only one direction in at least some of the myelinated axons in peripheral nerves. The objective of this study was to collect quantitative evidence for magnetically in...Magnetic stimulation; Peripheral nerve; Electromyographic potential; Somatosensory potential2006
38 Normann, Richard A.; Abbasi, Masoud; Johansson,TorbjornSilicon carbide enhanced thermomigrationThe widespread acceptance of thermomigration technology to produce through-chip interconnects has been impaired by (i) a random walk of the Si-Al liquid eutectic inclusion as it traverses the wafer, and (ii) a ?surface barrier? which allows thermomigration of only relatively large inclusions. In ...Silicon Dioxide; Thermometers; Transducers; Thermomigration Technology; Infrared Lamps1992
39 Christensen, Douglas A.; Herron, James N.Evanescent coupling in a waveguide fluoroimmunosensorA key factor in the analysis of evanescently-coupled optical sensors, such as the planar waveguide immunosensor analyzed here, is the efficiency of coupling between the optical waveguide modes and the fluorescent sources located on the surface of the waveguide. This is an important parameter in dete...Evanescent coupling; Waveguide; Fluoroimmunosensor1992
40 Horch, Kenneth W.Ontogeny of diving and feeding behavior in juvenile seaturtles: Leatherback Seaturtles (Dermochelys coriacea L) and Green Seaturtles (Chelonia mydas L) in the Florida CurrentWe compared activity, diving behavior and response to prey by Dermochelys coriacea and Chelonia mydas during their first 8-10 weeks of development.We reared juveniles in the laboratory and, at two-week intervals, released them in the ocean for a brief trial. Each turtle towed a device used to measur...Hatchlings; Posthatchling; Habitats2004
41 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
42 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
43 Normann, Richard A.; Muller, Jay F.; Kolb, HelgaSynaptic inputs to physiologically defined turtle retinal ganglion cellsTwo physiologically distinct, HRP-marked turtle retinal ganglion cells were examined for their morphology, GABAergic, glycinergic, and bipolar cell synaptic inputs, using electron-microscopic autoradiography and postembedding immunocytochemistry. One cell was a color-opponent, transient ON/OFF gangl...Turtles; Neural Pathways; Synapes; Retinal Ganglion Cells1991
44 Gesteland, Raymond F.Simian virus 40-specific polypeptides in Ad2+ND4- infected cellsA comparison of the proteins synthesized in human cells at late times after infection with adenovirus (Ad2) and with the adeno-simian virus 40 (SV40) hybrid viruses revealed polypeptides of 30,000 and 92,000 molecular weight specific for the hybrid viruses Ad2+ND1 and Ad2+ND4, respectively. Cell-fre...Molecular Weight; Peptide Biosynthesis; RNA, Messenger; Viral Proteins1976
45 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
46 Normann, Richard A.; Campbell, Patrick K.; Jones, Kelly E.100 electrode intracortical array: structural variabilityA technique has been developed for fabricating three dimensional "hair brush" electrode arrays from monocrystalline silicon blocks. Arrays consist of a square pattern of 100 penetrating electrodes, with 400 microns interelectrode spacing. Each electrode is 1.5mm in length and tapers from about 100 m...Microelectrode arrays; Stimulation; Micromachining1990
47 Christensen, Douglas A.Acoustic droplet vaporization, cavitation, and therapeutic properties of copolymer-stabilized perfluorocarbon nanoemulsionsAcoustic and therapeutic properties of Doxorubicin (DOX) and paclitaxel (PTX)-loaded perfluorocarbon nanoemulsions have been investigated in a mouse model of ovarian cancer. The nanoemulsions were stabilized by two biodegradable amphiphilic block copolymers that differed in the structure of the hydr...Cancer therapy; Targeted drug delivery; Nanobubbles; Ultrasound; Perfluoropentane2009
48 Christensen, Douglas A.Pulsed Schlieren system for visualizing beams from phased-array HIFU applicatorsWe have assembled a Schlieren system for imaging the beam patterns from HIFU transducers in water to verify the desired beam focusing and direction. It consists of a high power (65 mW) short-pulse (as short as 2 ns) laser emitting at 658 nm, a beam expander/spatial filter, water tank, 400 Jim round ...Ultrasound beam patterns; Pulsed laser; Wavefronts2007
49 Normann, Richard A.; Shoham, ShyCoding of position by simultaneously recorded sensory neurones in the cat dorsal root ganglionMuscle, cutaneous and joint afferents continuously signal information about the position and movement of individual joints. How does the nervous system extract more global information, for example about the position of the foot in space? To study this question we used microelectrode arrays to record...Cats; Sensory Neurones; Movement; Limb Position2004
50 Christensen, Douglas A.Ultrasound beam propagation using the hybrid angular spectrum methodWe introduce a fast and accurate numerical method for simulating the propagation of an ultrasound beam inside inhomogeneous tissue for mapping beam absorption, refraction and diffraction in the body. The technique, called the hybrid angular spectrum method, is an extension of the angular spectrum m...Ultrasound beam propagation; Medical ultrasound; Inhomogeneous tissue; Beam simulation2008-08
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