Automatic removal of high-amplitude artefacts from single-channel electroencephalograms

The offset panel is a display of basic seismic data which combines single‐channel profiles from successive offsets (source‐to‐receiver distances) into one format. The profiles are displayed one below another and arranged vertically by offset and horizontally by common‐depth‐point. This arrangement allows for comparison of variations observed at one offset to those at another offset. Alteration of the data due to near‐surface geologic variations generates geometric patterns on the display which are different from patterns due to changes in seismic source or receiver. This display has utility in data processing to verify field recording geometry, monitor the seismic source (primarily a marine application), and determine processing parameters. It aids data interpretation by allowing for the detection of an anomalous velocity zone in the near‐surface which may affect deeper structural interpretation. Utilization of the offset panel in identification of shallow events of high amplitude also allows identification of shallow drilling hazards in the marine environment with conventional seismic data.

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The mechanosensitive BKα/β1 channel localizes to cilia of principal cells in rabbit cortical collecting duct (CCD)

AJP Renal Physiology ◽

10.1152/ajprenal.00256.2016 ◽

2017 ◽

Vol 312 (1) ◽

pp. F143-F156 ◽

Cited By ~ 10

Author(s):

Rolando Carrisoza-Gaytán ◽

Lijun Wang ◽

Carlos Schreck ◽

Thomas R. Kleyman ◽

Wen-Hui Wang ◽

...

Keyword(s):

Single Channel ◽

Collecting Duct ◽

High Amplitude ◽

Bk Channels ◽

Bk Channel ◽

K Channel ◽

Cortical Collecting Duct ◽

Principal Cells ◽

High K ◽

Dependent Flow

Within the CCD of the distal nephron of the rabbit, the BK (maxi K) channel mediates Ca2+- and/or stretch-dependent flow-induced K+ secretion (FIKS) and contributes to K+ adaptation in response to dietary K+ loading. An unresolved question is whether BK channels in intercalated cells (ICs) and/or principal cells (PCs) in the CCD mediate these K+ secretory processes. In support of a role for ICs in FIKS is the higher density of immunoreactive apical BKα (pore-forming subunit) and functional BK channel activity than detected in PCs, and an increase in IC BKα expression in response to a high-K+ diet. PCs possess a single apical cilium which has been proposed to serve as a mechanosensor; direct manipulation of cilia leads to increases in cell Ca2+ concentration, albeit of nonciliary origin. Immunoperfusion of isolated and fixed CCDs isolated from control K+-fed rabbits with channel subunit-specific antibodies revealed colocalization of immunodetectable BKα- and β1-subunits in cilia as well as on the apical membrane of cilia-expressing PCs. Ciliary BK channels were more easily detected in rabbits fed a low-K+ vs. high-K+ diet. Single-channel recordings of cilia revealed K+ channels with conductance and kinetics typical of the BK channel. The observations that 1) FIKS was preserved but 2) the high-amplitude Ca2+ peak elicited by flow was reduced in microperfused CCDs subject to pharmacological deciliation suggest that cilia BK channels do not contribute to K+ secretion in this segment, but that cilia serve as modulators of cell signaling.

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Polarity Sensitivity in Pediatric and Adult Cochlear Implant Listeners

Trends in Hearing ◽

10.1177/2331216519862987 ◽

2019 ◽

Vol 23 ◽

pp. 233121651986298 ◽

Cited By ~ 2

Author(s):

Kelly N. Jahn ◽

Julie G. Arenberg

Keyword(s):

Cochlear Implant ◽

Dynamic Range ◽

Single Channel ◽

Spiral Ganglion ◽

High Amplitude ◽

Electrical Stimulus ◽

Polarity Sensitivity ◽

The Difference ◽

Phoneme Perception ◽

Ganglion Neurons

Modeling data suggest that sensitivity to the polarity of an electrical stimulus may reflect the integrity of the peripheral processes of the spiral ganglion neurons. Specifically, better sensitivity to anodic (positive) current than to cathodic (negative) current could indicate peripheral process degeneration or demyelination. The goal of this study was to characterize polarity sensitivity in pediatric and adult cochlear implant listeners (41 ears). Relationships between polarity sensitivity at threshold and (a) polarity sensitivity at suprathreshold levels, (b) age-group, (c) preimplantation duration of deafness, and (d) phoneme perception were determined. Polarity sensitivity at threshold was defined as the difference in single-channel behavioral thresholds measured in response to each of two triphasic pulses, where the central high-amplitude phase was either cathodic or anodic. Lower thresholds in response to anodic than to cathodic pulses may suggest peripheral process degeneration. On the majority of electrodes tested, threshold and suprathreshold sensitivity was lower for anodic than for cathodic stimulation; however, dynamic range was often larger for cathodic than for anodic stimulation. Polarity sensitivity did not differ between child- and adult-implanted listeners. Adults with long preimplantation durations of deafness tended to have better sensitivity to anodic pulses on channels that were estimated to interface poorly with the auditory nerve; this was not observed in the child-implanted group. Across subjects, duration of deafness predicted phoneme perception performance. The results of this study suggest that subject- and electrode-dependent differences in polarity sensitivity may assist in developing customized cochlear implant programming interventions for child- and adult-implanted listeners.

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Automatic removal of high-amplitude stimulus artefact from neuronal signal recorded in the subthalamic nucleus

Journal of Neuroscience Methods ◽

10.1016/j.jneumeth.2011.03.022 ◽

2011 ◽

Vol 198 (1) ◽

pp. 135-146 ◽

Cited By ~ 19

Author(s):

Tarik Al-ani ◽

Fanny Cazettes ◽

Stéphane Palfi ◽

Jean-Pascal Lefaucheur

Keyword(s):

Subthalamic Nucleus ◽

High Amplitude ◽

Stimulus Artefact ◽

Neuronal Signal ◽

Automatic Removal

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Data Acquisition and Handling Unit for a Quantitative Use of Electron Energy Loss Spectroscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100078699 ◽

1977 ◽

Vol 35 ◽

pp. 232-233 ◽

Cited By ~ 1

Author(s):

P. Trebbia ◽

P. Ballongue ◽

C. Colliex

Keyword(s):

Electron Microscope ◽

Energy Loss ◽

Electron Energy ◽

Electron Energy Loss Spectroscopy ◽

Single Channel ◽

Detection System ◽

Surface Barrier ◽

Solid State Detector ◽

Electrostatic Mirror ◽

Electron Energy Loss

An effective use of electron energy loss spectroscopy for chemical characterization of selected areas in the electron microscope can only be achieved with the development of quantitative measurements capabilities.The experimental assembly, which is sketched in Fig.l, has therefore been carried out. It comprises four main elements.The analytical transmission electron microscope is a conventional microscope fitted with a Castaing and Henry dispersive unit (magnetic prism and electrostatic mirror). Recent modifications include the improvement of the vacuum in the specimen chamber (below 10-6 torr) and the adaptation of a new electrostatic mirror.The detection system, similar to the one described by Hermann et al (1), is located in a separate chamber below the fluorescent screen which visualizes the energy loss spectrum. Variable apertures select the electrons, which have lost an energy AE within an energy window smaller than 1 eV, in front of a surface barrier solid state detector RTC BPY 52 100 S.Q. The saw tooth signal delivered by a charge sensitive preamplifier (decay time of 5.10-5 S) is amplified, shaped into a gaussian profile through an active filter and counted by a single channel analyser.

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Instrumentation for Measurement of Lingual Strength

Journal of Speech and Hearing Research ◽

10.1044/jshr.1101.189 ◽

1968 ◽

Vol 11 (1) ◽

pp. 189-193 ◽

Cited By ~ 1

Author(s):

Lois Joan Sanders

Keyword(s):

Single Channel ◽

Displacement Transducer ◽

Tongue Pressure ◽

Maximum Pressure ◽

Research Use ◽

Direct Writing ◽

Significant Difference ◽

Pressure Unit ◽

Force Displacement ◽

Consistent Response

A tongue pressure unit for measurement of lingual strength and patterns of tongue pressure is described. It consists of a force displacement transducer, a single channel, direct writing recording system, and a specially designed tongue pressure disk, head stabilizer, and pressure unit holder. Calibration with known weights indicated an essentially linear and consistent response. An evaluation of subject reliability in which 17 young adults were tested on two occasions revealed no significant difference in maximum pressure exerted during the two test trials. Suggestions for clinical and research use of the instrumentation are noted.

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