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76 Christensen, Douglas A.Planar waveguide biosensors for nucleic acid hybridization reactionsOligonucleotide probes derived from (1) the T3 RNA polymerase promoter sequence (T3) and (2) prostate-specific antigen messenger RNA (PSA) were prepared and labeled with a red-emitting fluorescent dye (Cy5). The complimentary oligonucleotides (anti T3 and anti PSA) were prepared and labeled with bio...Planar waveguides; Evanescence; Fluorescence; Glandular kallikrein; MDx; Molecular diagnostics; Nucleic acid; PSA; Oligonucleotide probes2000
77 Christensen, Douglas A.Plasma-etched polymer waveguides for intrachip optical interconnectsOptical intrachip communication offers the potential advantages of high speed and lack of electrical interference. We report on progress made on an interconnect design using GaAs LEDs, polymer waveguides, and photodiodes in a silicon substrate. The polymer waveguides are fabricated in polyimide or p...Polymer waveguides; Intrachip interconnects; LEDs1998
78 Gesteland, Raymond F.; Atkins, John F.; Felden, Brice; McCutcheon, John P.Probing the structure of the Escherichia coli 10Sa RNA (tmRNA)The conformation of the Escherichia coli 10Sa RNA (tmRNA) in solution was investigated using chemical and enzymatic probes. Single- and double-stranded domains were identified by hydrolysis of tmRNA in imidazole buffer and by lead(II)-induced cleavages. Ribonucleases T1 and S1 were used to map unpai...Covariation; Pseudoknot; Structural Probing; 10Sa RNA; tmRNA1997
79 Christensen, Douglas A.; Furse, Cynthia M.Problem and treatment of DC offsets in FDTD simulationsThis paper discusses the causes of and some solutions to the commonly observed problem of dc field offsets in finite-difference time-domain (FDTD) simulations. DC electric and magnetic field offsets are shown to be valid calculated responses of the modeled systems, resulting from interaction betwee...Finite-difference time-domain method; Direct current offsets; Waveforms2000-08
80 Horch, Kenneth W.Proposed specifications for a lumbar spinal cord electrode array for control of lower extremities in paraplegiaThe goal of the study was to provide specifications for a stimulating electrode array to be implanted in the lumbosacral spinal cord as part of a functional neuromuscular stimulation (FNS) system for control of lower extremity muscles in paralyzed individuals. Dual channel stimulation of the qua...Stimulating electrode array; FNS; Functional neuromuscular stimulation1997
81 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
82 Christensen, Douglas A.; Herron, James N.Rapid clinical diagnostics assays using injection-molded planar waveguidesThe goal of our research program is to develop an evanescent wave immunoassay system that can be used in point-of-care and critical care settings. Several key attributes are required to accomplish this goal: (i) the assay system should be at least as sensitive as present day immunoassays; (ii) assay...Planar waveguides; Creatine phosphokinase MB (CK-MB); Cardiac troponin I (cTnl); Diagnostics; Evanescence; Fluorescence; Human chorionic gonadotropin (hCG)1998
83 Christensen, Douglas A.; Herron, James N.Rapid single nucleotide polymorphism detection for personalized medicine applications using planar waveguide fluorescence sensorsPersonalized medicine is an emerging field in which clinical diagnostics information about a patient's genotype or phenotype is used to optimize his/her pharmacotherapy. This article evaluates whether planar waveguide fluorescent sensors are suitable for determining such information from patient tes...Personalized medicine; Planar waveguides; Fluorescence sensors; Evanescent excitation; Fluorescence; Hybridization; Molecular diagnostics; Peptide nucleic acid; Point of care; Single base extension; Single nucleotide polymorphism2006
84 Christensen, Douglas A.Resonant inductive applicator for neck hyperthermiaWe have designed and phantom tested an inductive applicator especially suited for producing hyperthermia in cancerous regions in the neck. The applicator is tuned to resonate near 27 MHz; its inductive nature has the advantage of efficient coupling to the irregular neck anatomy. An inhomogeneou...Hyperthermia applicator; Phantom tests1989
85 Varner, Michael W.; Clark, Edward B.; Fernando, Kumari L.; Mathews, V. JohnRobust estimation of fetal heart rate variability using Doppler ultrasound.This paper presents a new measure of heart rate variability (HRV) that can be estimated using Doppler ultrasound techniques and is robust to variations in the angle of incidence of the ultrasound beam and the measurement noise. This measure employs the multiple signal characterization (MUSIC) algori...Prenatal Ultrasonography; Fetal Heart Rate; Blood Flow Velocity; Algorithms2003-08
86 Gesteland, Raymond F.; Atkins, John F.; Wills, Norma M.rRNA-mRNA base pairing stimulates a programmed -1 ribosomal frameshiftBase 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 Composition1994
87 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
88 Horch, Kenneth W.Selective activation of muscle groups in the feline hindlimb thorough electrical microstimulation of the ventral lumbo-sacral spinal cordSelective activation of muscle groups in the feline hindlimb by electrical stimulation of the ventral lumbo-sacral spinal cord was investigated. Spinal cord segments L5 to S1 were mapped using a penetrating tungsten needle electrode. Locations that produced isolated contraction of quadriceps, ti...Functional electrical stimulation; Motor pools; Spinal chord stimulation2000
89 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
90 Horch, Kenneth W.Selective stimulation of peripheral nerve fibers using dual intrafascicular electrodesWe 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 array1993
91 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
92 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
93 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
94 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
95 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
96 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
97 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
98 Gesteland, Raymond F.; Atkins, John F.; Weiss, Robert B.Slippery runs, shifty stops, backward steps and forward hops: -2, -1, +1, +2, +5 and +6 Ribosomal frameshiftingFrameshift mutations frequently express residual levels of gene activity; that is, they are often leaky. This leakiness can be used as a tool to define the functional components that affect the reading frame during gene expression. Recent technological advances in the capability to efficiently bu...Molecular Sequence Data; Mutation; RNA, Transfer; Frameshifting1987
99 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
100 Normann, Richard A.; Johansson,Torbjorn; Abbasi, Masoud; Huber, Robert J.Three-dimensional architecture for a parallel processing photosensing arrayA three-dimensional architecture for a photosensing array has been developed. This silicon based architecture consists of a 10 x 10 array of photosensors with 80 microns diameter, through chip interconnects to the back side of a 500 microns thick silicon wafer. Each photosensor consists of a 300 x 3...Retina; Optics; Silicon; Photosensing1992
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