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1 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
2 Horch, Kenneth W.Acoustic interneurons of fiddler and ghost crabsThe properties of acoustic interneurons in fiddler (Uca pugilalor and U. minax) and ghost (Ocvpade qucldrula) crabs are described, as revealed bv tests with pure tones. Three types of interneurons were present in all species: tonic, which fired for the duration of the stimulus; phasic, which fire...Acoustic crabs; Neural recording; Vibration reception1976
3 Horch, Kenneth W.Action potential classification with dual channel intrafascicular electrodesUsing 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 recording1994
4 Gesteland, Raymond F.; Ives, Jeffrey T.; Stockham, Thomas G.Automated film reader for DNA sequencing based on homomorphic deconvolutionAn 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 Deconvolution1994
5 Christensen, Douglas A.Biosensor development at the University of UtahInterest 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 waveguide1994-07
6 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
7 Horch, Kenneth W.Changes in primary afferent depolarization of sensory neurones during peripheral nerve regeneration in the catI. Micro-electrode recordings were made from normal and regenerating sural nerve fibres in cats. Increases in the excitability of the central terminals of these fibres after conditioning stimulation of other sural nerve fibres were taken as evidence for primary afferent depolarization. 2. At all...Micro-electrode recording; Nerve regeneration; Primary afferent depolarization1981
8 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
9 Horch, Kenneth W.Classification of action potentials in multi unit intrafascicular recordings using neural network pattern recognition techniquesNeural 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 networks1994
10 Horch, Kenneth W.Closed loop control of ankle position using muscle afferent feedback with functional neuromuscular stimulationThis 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 electrodes1996
11 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
12 Christensen, Douglas A.Computer-aided design of two-dimensional electric-type hyperthermia applicators using the finite-difference time-domain methodA hyperthermia applicator design tool consisting of a finite-difference time-domain (FDTD) technique in combination with a graphical display of electric fields and normalized linear temperature rise is described. This technique calculates, rather than assumes, antenna current distributions; it incl...Finite-difference time-domain method; Hyperthermia applicator1991-09
13 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
14 Normann, Richard A.Control of retinal sensitivity. I. Light and dark adaptation of vertebrate rods and conesRods and cones in Necturus respond with graded hyperpolarization to test flashes spanning about 3.5 log units of intensity. Steady background levels hyperpolarize the rods, and the rod responses become progressively smaller as background level is increased. In cones, higher background levels reduce...Retina;Light and Dark Adaptation; Recepters; Bipolars; Ganglion Cells1974
15 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
16 Normann, Richard A.Effects of background illumination on the photoresponses of red and green cones1. The photoresponses of light- and dark-adapted red and green cone photoreceptors were recorded intracellularly in the retina of the turtle, Pseduemys scripta elegans. Background illumination produced similar effects on both types of cones. 2. In response to the onset of a prolonged, steady backgro...Turtles; Adaptation, Ocular; Retina; Signal Transmission1979
17 Normann, Richard A.; Chandler, John P.Effects of calcium ions on L-type horizontal cells in the isolated turtle retinaA technique by which the retina can be isolated from the turtle eye is described. Scanning electron microscopy revealed morphological variability between preparations and also between regions of the same one. Large areas were often totally free of any pigment epithelial cells, yet contained a high p...Retina; Calcium; Horizontal Cell; Turtle1990
18 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
19 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
20 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 Theory1996-06
21 Gesteland, Raymond F.; Weiss, Robert B.Efficient shine- Dalgarno sequence but not translation is necessary for LacZ mRNA stability in Escherichia coliThe 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 Sequence1994
22 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
23 Christensen, Douglas A.Extending the two-dimensional FDTD method to hybrid electromagnetic systems with active and passive lumped elementsThis 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 elements1992-04
24 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
25 Christensen, Douglas A.; Vincent, G. MichaelFiberoptic laser angioplasty probe with optical steerabilityWe have designed and bench tested an optically steerable fiberoptic probe for use in laser angioplasty. The unique feature of this design is the use of a gradient-index (GRIN) lens attached to the distal end of a seven-fiber bundle. By selecting which fiber of the bundle is illuminated by the source...Fiberoptic probe; GRIN lens; Steerability1990
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