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Creator | Title | Description | Subject | Date |
| 51 |
 |
Normann, Richard A.; Horch, Kenneth W.; Cha, Kichul | Mobility performance with a pixelized vision system | A visual prosthesis, based on electrical stimulation of the visual cortex, has been suggested as a means for partially restoring functional vision in the blind. The prosthesis would create a pixelized visual sense consisting of punctate spots of light (phosphenes). The present study investigated the... | Visual Prosthesis; Mobility; Phosphene Simulator | 1992 |
| 52 |
 |
Christensen, Douglas A. | Extending the two-dimensional FDTD method to hybrid electromagnetic systems with active and passive lumped elements | This paper extends the finite-difference time-domain (FDTD) method to include distributed electromagnetic systems with lumped elements (a hybrid system) and voltage and current sources. FDTD equations that include nonlinear elements like diodes and transistors are derived. Calculation of driving-p... | Finite-difference time-domain method; Lumped elements | 1992-04 |
| 53 |
 |
Horch, Kenneth W. | Selective activation of functional muscle groups through stimulation of spinal motor pools | A 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 pools | 1993 |
| 54 |
 |
Christensen, Douglas A.; Herron, James N. | Comparison of robust coupling techniques for planar waveguide immunosensors | We 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 coupler | 1993 |
| 55 |
 |
Horch, Kenneth W. | Selective stimulation of peripheral nerve fibers using dual intrafascicular electrodes | We have studied activation of newe fibers by pairs of Pt-Ir wire electrodes implanted within single fascicles of the nerve innervating the gastrocnemius muscle in cats. The purpose of this study was to determine if these intrafascicular electrodes can activate nerve fibers in different fascicles... | Functional electrical stimulation; Intrafascicular stimulation; Silicon electrode array | 1993 |
| 56 |
 |
Gesteland, Raymond F.; Weiss, Robert B. | Efficient shine- Dalgarno sequence but not translation is necessary for LacZ mRNA stability in Escherichia coli | The 5' ends of many bacterial transcripts are important in determining mRNA stability. A series of Shine-Dalgarno (SD) sequence changes showed that the complementarity of the SD sequence to the anti-SD sequence of 16S rRNA correlates with lacZ mRNA stability in Escherichia coli. Several initiation c... | Protein Biosynthesis; Ribosomes; Escherichia coli; Shine-Dalgarno Sequence | 1994 |
| 57 |
 |
Gesteland, Raymond F.; Ives, Jeffrey T.; Stockham, Thomas G. | Automated film reader for DNA sequencing based on homomorphic deconvolution | An automated reader for electrophoresis based DNA sequencing methods is described that provides fast and accurate sequence determination. Digitized sequencing lanes are processed with homomorphic blind deconvolution in preparation for peak detection, interlane alignment, peak refinement and base cal... | Sequence Analysis; Electrophoresis; Automated Film Reader; Homomorphic Deconvolution | 1994 |
| 58 |
 |
Gesteland, Raymond F.; Atkins, John F.; Tuohy, Therese M. | Uninterrupted translation through putative 12-nucleotide coding gap in sequence of carA: business as usual | Previous 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 Deletion | 1994 |
| 59 |
 |
Horch, Kenneth W. | Mechanical testing of metallic and polymeric intrafascicular electrodes | We 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 fibers | 1994 |
| 60 |
 |
Horch, Kenneth W. | Classification of action potentials in multi unit intrafascicular recordings using neural network pattern recognition techniques | Neural network pattern-recognition techniques were applied to the problem of identifying the sources of action potentials in multi-unit neural recordings made from intrafascicular electrodes implanted in cats. The network was a three-layer connectionist machine that used digitized action potenti... | Intrafascicular electrodes; Multi-unit neural activity; Artificial neural networks | 1994 |
| 61 |
 |
Gesteland, Raymond F.; Atkins, John F.; Wills, Norma M. | rRNA-mRNA base pairing stimulates a programmed -1 ribosomal frameshift | Base pairing between the 3' end of 16S rRNA and mRNA is shown to be important for the programmed -1 frameshifting utilized in decoding the Escherichia coli dnaX gene. This pairing is the same as the Shine-Dalgarno pairing used by prokaryotic ribosomes in selection of translation initiators, but for ... | Frameshifting; Escherichia coli; Binding Sites; Base Composition | 1994 |
| 62 |
 |
Horch, Kenneth W. | Tracking changes in action potential shapes in chronic multi-unit intrafascicular recordings using neural network pattern recognition techniques | A 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 network | 1994 |
| 63 |
 |
Horch, Kenneth W. | Control of ankle position using neural feedback | This 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 angle | 1994 |
| 64 |
 |
Horch, Kenneth W. | Action potential classification with dual channel intrafascicular electrodes | Using recordings of peripheral nerve activity made with carbon fiber intrafascicular electrodes, we compared the performance of three different recording techniques (single channel, differential, and dual channel) and four different unit classification methods (linear discriminant analysis, temp... | Carbon fiber intrafascicular electrodes; Dual channel recording | 1994 |
| 65 |
 |
Christensen, Douglas A. | Biosensor development at the University of Utah | Interest in biosensors has increased rapidly in the past few years due to the many potential advantages of these devices, such as small size, speed of response, and specificity 111. The term "biosensor" in the broad sense describes any device or apparatus which detects biological signals for the pu... | Silicon retina; Photosensing array; CHEMFET; Fluorescence lmmunosensor; Planar waveguide | 1994-07 |
| 66 |
 |
Gesteland, Raymond F.; Krapcho, Karen J.; Talbot, Phil; Thulin, Craig | Crystallization of the MS2 translational repressor alone and complexed to bromouridine | The 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 Repressor | 1995 |
| 67 |
 |
Horch, Kenneth W. | Perspectives on new electrode technology for stimulating peripheral nerves with implantable motor prostheses | Abstract-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; Electrodes | 1995 |
| 68 |
 |
Normann, Richard A. | Visual Neuroprosthetics: Functional Vision for the Blind | Resent progress in materials and microfabrication technologies have allowed researchers to reconsider the prospect of providing a useful visual sense to the profoundly blind. This will be accomplished by electrically stimulating their visual systems via an array of implanted microelectrodes. T... | Visual Neuroprosthetics; Vision; Blindness | 1995-01 |
| 69 |
 |
Christensen, Douglas A. | Modeling sources in the FDTD formulation and their use in quantifying source and boundary condition errors | The 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 element | 1995-04 |
| 70 |
 |
Horch, Kenneth W. | Closed loop control of ankle position using muscle afferent feedback with functional neuromuscular stimulation | This paper describes a closed-loop functional neuromuscular stimulation system that uses afferent neural activity from muscle spindle fibers as feedback for controlling position of the ankle joint. Ankle extension against a load was effected by neural stimulation through a dual channel intrafasc... | Neuromuscular stimulation; Functional neuromuscular stimulation (FNS); Neural electrodes | 1996 |
| 71 |
 |
Christensen, Douglas A.; Herron, James N. | Optical immunoassay systems based upon evanescent wave interactions | Immunoassays based upon evanescent wave interactions are finding increased biosensing application. In these devices, the evanescent tail associated with total internal reflection of an incident beam at the substrate/solution interface provides sensitivity for surface-bound proteins over bulk molec... | Diagnostics; Evanescence; Planar waveguides; Human chorionic gonadotropin (hCG) | 1996 |
| 72 |
 |
Christensen, Douglas A. | General formulation for connecting sources and passive lumped-circuit elements across multiple 3-D FDTD cells | A previous extension of the finite-difference time-domain (FDTD) method to include lumped-circuit elements is further extended to model lumped-element circuits connected across multiple FDTD cells. This formulation is needed to model many kinds of circuits, like those with a transistor or other ac... | Finite-difference time-domain method; Lumped-element circuit; Dielectric; Microstrip | 1996-02 |
| 73 |
 |
Hendee, Shonn P.; Faour, Fouad A.; Christensen, Douglas A.; Patrick, Baharah; Durney, Carl H.; Blumenthal, Donald K. | Effects of weak extremely low frequency magnetic fields on calcium/calmodulin interactions. | Mechanisms by which weak electromagnetic fields may affect biological systems are of current interest because of their potential health effects. Lednev has proposed an ion parametric resonance hypothesis (Lednev, 1991, Bioelectromagnetics, 12:71-75), which predicts that when the ac, frequency of a c... | Electromagnetic Fields; Calcium-binding Proteins; Lednev's Theory | 1996-06 |
| 74 |
 |
Normann, Richard A.; Jones, Kelly E. | Advanced demultiplexing system for physiological stimulation | A CMOS very large scale integration (VLSI) chip has been designed and built to implement a scheme developed for multiplexing/demultiplexing the signals required to operate an intracortical stimulating electrode array. Because the use of radio telemetry in a proposed system utilizing this chip may im... | Electrode Array; Stimulation; Telemetry; Microelectrodes; Transistors | 1997 |
| 75 |
 |
Horch, Kenneth W. | Electrical stimulation of the ventral lumbo-sacral spinal cord results in mixed recruitment order of quadriceps and tibialis anterior motor units | Pulse width modulated, twitch recruitment curves for quadriceps and tibialis anterior were obtained by stimulating their respective motor activation pools in the ventral lumbo-sacral portion of the spinal cord. The duration of the twitch responses were analyzed as a function of stimulus strength ... | Quadriceps; Tibialis anterior; Ventral lumbo-sacral spinal cord; Reversed recruitment | 1997 |
