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26 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
27 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
28 Crystallization 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
29 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
30 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
31 Dispersion effects in fiber optic interferometryAn extended analysis of the effects of uncompensated fiber dispersion on the fringe visibility of a fiber optic interferometer is developed, with particular emphasis on stellar interferometry. Both material and waveguide dispersion for single-mode, polarization-preserving fibers are considered. It...Stellar interferometry; Fiber optics; Statistical optics1997
32 Dual-luciferase reporter system for studying recoding signalsA new reporter system has been developed for measuring translation coupling efficiency of recoding mechanisms such as frameshifting or readthrough. A recoding test sequence is cloned in between the renilla and firefly luciferase reporter genes and the two luciferase activities are subsequently measu...Amino Acid Sequence; Genes, Reporter; HIV; Antizyme; Translation1998
33 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
34 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
35 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
36 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
37 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
38 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
39 Electrical stimulation of the ventral lumbo-sacral spinal cord results in mixed recruitment order of quadriceps and tibialis anterior motor unitsPulse 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 recruitment1997
40 Encoding mechanisms for sensory neurons studied with a multielectrode array in the cat dorsal root ganglionRecent advances in microelectrode array technology now permit a direct examination of the way populations of sensory neurons encode information about a limb's position in space. To address this issue, we recorded nerve impulses from about 100 single units simultaneously in the L6 and L7 dorsal root ...Sensory; Encoding; Multielectrode; Dorsal Root Ganglion; Cutaneour; Muscle2004
41 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
42 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
43 Experience with the first three years of an accelerated dual-degree program in biomedical engineeringOur Department of Bioengineering has instituted a pilot program aimed at helping a select group of highly qualified students obtain both bachelor's and master's degrees in an accelerated timeframe-approximately four years from the beginning of their university studies. A key element of this progra...Accelerated; Dual-degrees; Education2004
44 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
45 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
46 Fiberoptic 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
47 Finite-difference time-domain modeling and experimental characterization of planar waveguide fluorescence sensorsThe finite-difference time-domain method (FDTD) is a powerful numerical technique for solving Maxwell's equations in a discretized space and time grid. Its applications have up to now been in the analysis of electrically large structures in the microwave domain, and the scope of investigations has b...Finite-difference time-domain method; Planar waveguide1992
48 Frameshifting in gene 10 of bacteriophage T7Gene 10 of bacteriophage T7, which encodes the most abundant capsid protein, has two products: a major product, 10A (36 kDa), and a minor product, 10B (41 kDa). 10B is produced by frameshifting into the -1 frame near the end of the 10A coding frame and is incorporated into the capsid. The frameshift...Frameshifting; Bacteriophage T7; RNA, Viral; Gene Expression1991
49 Functional reorganization of primary visual cortex induced by electrical stimulation in the cat.Compared to the high degree of plasticity observed in a juvenile, mature sensory cortices have long been held to be immutable but, recently, researchers have suggested some plasticity persists in the mature cortex. Cortical reorganization has particular saliency to the development of a cortically ba...Cat; Electrophysiology; Phosphene; Plasticity; Receptive Field; Striate Cortex2005
50 General formulation for connecting sources and passive lumped-circuit elements across multiple 3-D FDTD cellsA 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; Microstrip1996-02
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