Theoretical aspects of metal-electrolyte interfaces Final report
Skin surface electrode and electrochemical cell characteristics for human bioelectric response determinations
BIOELECTRICITY↗
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Results for “bioelectricity”
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Heterosensory and Heterocortical Activation of the Purkinje Neuron
Bioelectric potential measurements of convergence of heterogeneous afferents at single neuron level in cerebellar cortex
CENTRAL NERVOUS SYSTEM↗
Investigation of the relationship between the oxygen metabolism of the brain, its electrical activity and the conditioned reflex activity of animals after vibration
Oxygen metabolism of brain, its bioelectric capacity, and conditioned reflexes of rats following vibration exposure
CONDITIONED RESPONSE↗
Structural basis for saxitoxin congener binding and neutralization by anuran saxiphilins
Dinoflagellates and cyanobacteria produce saxitoxin (STX) and ~50 congeners that disrupt bioelectrical signals by blocking voltage-gated sodium channels (NaVs). Consuming seafood carrying these toxins causes paralytic shellfish poisoning (PSP). Although NaVs and anuran STX binding proteins (saxiphilins, Sxphs) use convergent STX binding modes, the structural basis for STX congener recognition is unknown. Here, we show that American bullfrog (Rana catesbeiana) RcSxph and High Himalaya frog (Nanorana parkeri) NpSxph sequester STX congeners using a ‘lock and key’ mode shared with STX. Importantly, functional studies demonstrate that Sxph ‘toxin sponges’ reverse NaV block by multiple STX congeners and detect these toxins in a radioligand binding assay (RBA) used for environmental testing. Together, our study establishes how Sxphs sequester select neurotoxins and uncover STX congener-specific interactions distinct from NaVs. These findings expand understanding of toxin sponge action and provide a foundation for strategies to monitor and mitigate the harmful effects of STX congeners.
Zakrzewska, Sandra↗
Electrosome assembly: Structural insights from high voltage-activated calcium channel (CaV)–chaperone interactions
Ion channels are multicomponent complexes (termed here as“electrosomes”) that conduct the bioelectrical signals required for life. It has been appreciated for decades that assembly is critical for proper channel function, but knowledge of the factors that undergird this important process has been lacking. Although there are now exemplar structures of representatives of most major ion channel classes, there has been no direct structural information to inform how these complicated, multipart complexes are put together or whether they interact with chaperone proteins that aid in their assembly. Recent structural characterization of a complex of the endoplasmic membrane protein complex (EMC) chaperone and a voltage-gated calcium channel (CaV) assembly intermediate comprising the pore-forming CaVα1 and cytoplasmic CaVβ subunits offers the first structural view into the assembly of a member of the largest ion channel class, the voltagegated ion channel (VGIC) superfamily. The structure shows how the EMC remodels the CaVα1/CaVβ complex through a set of rigid body movements for handoff to the extracellular CaVα2δ subunit to complete channel assembly in a process that involves intersubunit coordination of a divalent cation and ordering of CaVα1 elements. These findings set a new framework for deciphering the structural underpinnings of ion channel biogenesis that has implications for understanding channel function, how drugs and disease mutations act, and for investigating how other membrane proteins may engage the ubiquitous EMC chaperone.
Biochemistry & Molecular Biology↗
Miniature electrometer preamplifier effectively compensates for input capacitance
Negative capacitance preamplifier using a dual MOS /Metal Oxide Silicon/ transistor in conjunction with bipolar transistors is used with intracellular microelectrodes in recording bioelectric potentials. Applications would include use as a pickup plate video amplifier in storage tube tests and for pH and ionization chamber measurements.
Burrous, C. N.↗
A survey of in vivo energy sources
Bioelectric potentials, muscle motions, and implanted fuel cells as energy sources for bioinstrumentation in situ
Konikoff, J. J.↗
Electrode for biological recording
Electrochemically reversible silver-silver chloride electrode for detecting bioelectric potential differences generated by human muscles and organs
Day, J. L.↗
Problem of the origin of optic disorders during acceleration
Acceleration effects on bioelectric activity of human retina
Savin, B. M.↗
Classification of the electroencephalogram of a healthy subject /in relation to the problems of selection in aviation/
Electroencephalogram classification of bioelectric activity in human brain
Malkin, V. B.↗
Extravehicular attitude control by use of head motions
Extravehicular attitude control using bioelectric currents generated in muscle tissue by head motion
Von Renner, L. C.↗
Cardiac R-wave detector with automatic sensitivity control
An electronic circuit that automatically changes its sensitivity was developed for detecting the bioelectric signal resulting from activation of the heart's ventricles. Regulation of sensitivity was accomplished with two feedback channels that maintain the sensitivity level between an upper and a lower limit. These limits are proportional to the R-wave amplitude. Tests on an experimental circuit demonstrated a capability to reject unwanted signal noise, illustrated difficulties encountered without sensitivity control, and presented closed loop transients which occurred for step changes in R-wave amplitude.
Gebben, V. D.↗
Bio-isolated dc operational amplifier
A bio-isolated dc operational amplifier is described for use in making bioelectrical measurements of a patient while providing isolation of the patient from electrical shocks. The circuit contains a first operational amplifier coupled to the patient with its output coupled in a forward loop through a first optic coupler to a second operational amplifier. The output of the second operational amplifier is coupled to suitable monitoring circuitry via a feedback circuit including a second optic coupler to the input of the first operational amplifier.
Lee, R. D.↗
Implantable electrode for recording nerve signals in awake animals
An implantable electrode assembly consisting of collagen and metallic electrodes was constructed to measure simultaneously neural signals from the intact nerve and bioelectrical noises in awake animals. Mechanical artifacts, due to bodily movement, were negligibly small. The impedance of the collagen electrodes, measured in awake cats 6-7 days after implantation surgery, ranged from 39.8-11.5 k ohms at a frequency range of 20-5 kHz. Aortic nerve activity and renal nerve activity, measured in awake conditions using the collagen electrode, showed grouped activity synchronous with the cardiac cycle. Results indicate that most of the renal nerve activity was from postganglionic sympathetic fibers and was inhibited by the baroceptor reflex in the same cardiac cycle.
Ninomiya, I.↗
Mechanical and chemical effects of ion-texturing biomedical polymers
To determine whether sputter etching may provide substantial polymer surface texturing with insignificant changes in chemical and mechanical properties, an 8 cm beam diameter, electron bombardment, argon ion source was used to sputter etch (ion-texture process) nine biomedical polymers. The materials included silicone rubber, 32% carbon impregnated polyolefin, polyoxymethylene, polytetrafluoroethylene, ultrahigh molecular weight (UHMW) polyethylene, UHMW polyethylene with carbon fibers (10%), and several polyurethanes (bioelectric, segmented, and cross linked). Ion textured microtensile specimens of each material except UHMW polyethylene and UHMW polyethylene with 10% carbon fibers were used to determine the effect of ion texturing on tensile properties. Scanning electron microscopy was used to determine surface morphology changes, and electron spectroscopy for chemical analysis was used to analyze the near surface chemical changes that result from ion texturing. Ion energies of 500 eV with beam current densities ranging from 0.08 to 0.19 mA/sq cm were used to ion texture the various materials. Standard microtensile specimens of seven polymers were exposed to a saline environment for 24 hours prior to and during the tensile testing. The surface chemical changes resulting from sputter etching are minimal in spite of the often significant changes in the surface morphology.
Weigand, A. J.↗
The space flight of the Soviet-Indian crew
After a brief discussion of the Indian space program, the paper examines the flight of the Soyuz T-11, which included an Indian crew member. Particular attention is given to experiments conducted aboard Soyuz T-11, including the Optokinez vestibular experiment, the Vektor cardiac bioelectricity experiment, the yoga experiment for the counteraction of the negative effects of weightlessness, a supercooling experiment, and the Terra remote sensing experiment.
Nikitin, S. A.↗
Possible effects of organelle charge and density on cell metabolism
A system of perception and transduction involving the gravity-induced asymmetric distribution of a plant growth hormone is studied. A theory is constructed which assumes that the perception of the gravitational stimulus involved a perturbation of the plant's bioelectric field and that the transduction of the stimulus involved voltage-gating of hormone movement from the plant's vascular tissue into the hormone responsive growing tissue. Particular attention is focused on the barriers to indole-3-acetic acid (IAA) transport from the seed to the mesocotyl cortex, the protoinhibition of IAA movement from the endosperm to the shoot, the effects of the gravitational stimulus on the movement of IAA from the kernel to the shoot, electrochemical gating as a target for the gravity stimulus, and the gravity sensing mechanism.
Bandurski, Robert S.↗
The N2-P3 complex of the evoked potential and human performance
The N2-P3 complex and other endogenous components of human evoked potential provide a set of tools for the investigation of human perceptual and cognitive processes. These multidimensional measures of central nervous system bioelectrical activity respond to a variety of environmental and internal factors which have been experimentally characterized. Their application to the analysis of human performance in naturalistic task environments is just beginning. Converging evidence suggests that the N2-P3 complex reflects processes of stimulus evaluation, perceptual resource allocation, and decision making that proceed in parallel, rather than in series, with response generation. Utilization of these EP components may provide insights into the central nervous system mechanisms modulating task performance unavailable from behavioral measures alone. The sensitivity of the N2-P3 complex to neuropathology, psychopathology, and pharmacological manipulation suggests that these components might provide sensitive markers for the effects of environmental stressors on the human central nervous system.
Odonnell, Brian F.↗