Electrodes: Electric conductors through which electric currents enter or leave a medium, whether it be an electrolytic solution, solid, molten mass, gas, or vacuum.Electrodes, Implanted: Surgically placed electric conductors through which ELECTRIC STIMULATION is delivered to or electrical activity is recorded from a specific point inside the body.Ion-Selective Electrodes: Electrodes which can be used to measure the concentration of particular ions in cells, tissues, or solutions.Electrochemistry: The study of chemical changes resulting from electrical action and electrical activity resulting from chemical changes.Electrochemical Techniques: The utilization of an electrical current to measure, analyze, or alter chemicals or chemical reactions in solution, cells, or tissues.Microelectrodes: Electrodes with an extremely small tip, used in a voltage clamp or other apparatus to stimulate or record bioelectric potentials of single cells intracellularly or extracellularly. (Dorland, 28th ed)Potentiometry: Solution titration in which the end point is read from the electrode-potential variations with the concentrations of potential determining ions. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Fluorocarbon PolymersGraphite: An allotropic form of carbon that is used in pencils, as a lubricant, and in matches and explosives. It is obtained by mining and its dust can cause lung irritation.Biosensing Techniques: Any of a variety of procedures which use biomolecular probes to measure the presence or concentration of biological molecules, biological structures, microorganisms, etc., by translating a biochemical interaction at the probe surface into a quantifiable physical signal.Equipment Design: Methods of creating machines and devices.Electric Stimulation: Use of electric potential or currents to elicit biological responses.Gold: A yellow metallic element with the atomic symbol Au, atomic number 79, and atomic weight 197. It is used in jewelry, goldplating of other metals, as currency, and in dental restoration. Many of its clinical applications, such as ANTIRHEUMATIC AGENTS, are in the form of its salts.Cochlear Implants: Electronic hearing devices typically used for patients with normal outer and middle ear function, but defective inner ear function. In the COCHLEA, the hair cells (HAIR CELLS, VESTIBULAR) may be absent or damaged but there are residual nerve fibers. The device electrically stimulates the COCHLEAR NERVE to create sound sensation.Conductometry: Determination of the quantity of a material present in a mixture by measurement of its effect on the electrical conductivity of the mixture. (Webster, 3d ed)Cochlear Implantation: Surgical insertion of an electronic hearing device (COCHLEAR IMPLANTS) with electrodes to the COCHLEAR NERVE in the inner ear to create sound sensation in patients with residual nerve fibers.Electric Impedance: The resistance to the flow of either alternating or direct electrical current.Enzymes, Immobilized: Enzymes which are immobilized on or in a variety of water-soluble or water-insoluble matrices with little or no loss of their catalytic activity. Since they can be reused continuously, immobilized enzymes have found wide application in the industrial, medical and research fields.Carbon: A nonmetallic element with atomic symbol C, atomic number 6, and atomic weight [12.0096; 12.0116]. It may occur as several different allotropes including DIAMOND; CHARCOAL; and GRAPHITE; and as SOOT from incompletely burned fuel.Electroencephalography: Recording of electric currents developed in the brain by means of electrodes applied to the scalp, to the surface of the brain, or placed within the substance of the brain.Electricity: The physical effects involving the presence of electric charges at rest and in motion.Electric Stimulation Therapy: Application of electric current in treatment without the generation of perceptible heat. It includes electric stimulation of nerves or muscles, passage of current into the body, or use of interrupted current of low intensity to raise the threshold of the skin to pain.Equipment Failure Analysis: The evaluation of incidents involving the loss of function of a device. These evaluations are used for a variety of purposes such as to determine the failure rates, the causes of failures, costs of failures, and the reliability and maintainability of devices.Bioelectric Energy Sources: Electric power supply devices which convert biological energy, such as chemical energy of metabolism or mechanical energy of periodic movements, into electrical energy.Deep Brain Stimulation: Therapy for MOVEMENT DISORDERS, especially PARKINSON DISEASE, that applies electricity via stereotactic implantation of ELECTRODES in specific areas of the BRAIN such as the THALAMUS. The electrodes are attached to a neurostimulator placed subcutaneously.Action Potentials: Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.Electromyography: Recording of the changes in electric potential of muscle by means of surface or needle electrodes.Tin Compounds: Inorganic compounds that contain tin as an integral part of the molecule.Silver Compounds: Inorganic compounds that contain silver as an integral part of the molecule.Electrophysiology: The study of the generation and behavior of electrical charges in living organisms particularly the nervous system and the effects of electricity on living organisms.Platinum: Platinum. A heavy, soft, whitish metal, resembling tin, atomic number 78, atomic weight 195.09, symbol Pt. (From Dorland, 28th ed) It is used in manufacturing equipment for laboratory and industrial use. It occurs as a black powder (platinum black) and as a spongy substance (spongy platinum) and may have been known in Pliny's time as "alutiae".Dielectric Spectroscopy: A technique of measuring the dielectric properties of materials, which vary over a range of frequencies depending on the physical properties of the material. The technique involves measuring, over a range of frequencies, ELECTRICAL IMPEDANCE and phase shift of an electric field as it passes through the material.Calibration: Determination, by measurement or comparison with a standard, of the correct value of each scale reading on a meter or other measuring instrument; or determination of the settings of a control device that correspond to particular values of voltage, current, frequency or other output.Subdural Space: Potential cavity which separates the ARACHNOID MATER from the DURA MATER.Signal Processing, Computer-Assisted: Computer-assisted processing of electric, ultrasonic, or electronic signals to interpret function and activity.Polyvinyl Chloride: A polyvinyl resin used extensively in the manufacture of plastics, including medical devices, tubing, and other packaging. It is also used as a rubber substitute.Ferrocyanides: Inorganic salts of the hypothetical acid ferrocyanic acid (H4Fe(CN)6).Glucose Oxidase: An enzyme of the oxidoreductase class that catalyzes the conversion of beta-D-glucose and oxygen to D-glucono-1,5-lactone and peroxide. It is a flavoprotein, highly specific for beta-D-glucose. The enzyme is produced by Penicillium notatum and other fungi and has antibacterial activity in the presence of glucose and oxygen. It is used to estimate glucose concentration in blood or urine samples through the formation of colored dyes by the hydrogen peroxide produced in the reaction. (From Enzyme Nomenclature, 1992) EC 1.1.3.4.Nanotubes, Carbon: Nanometer-sized tubes composed mainly of CARBON. Such nanotubes are used as probes for high-resolution structural and chemical imaging of biomolecules with ATOMIC FORCE MICROSCOPY.Electric Countershock: An electrical current applied to the HEART to terminate a disturbance of its rhythm, ARRHYTHMIAS, CARDIAC. (Stedman, 25th ed)Scala Tympani: The lower chamber of the COCHLEA, extending from the round window to the helicotrema (the opening at the apex that connects the PERILYMPH-filled spaces of scala tympani and SCALA VESTIBULI).Electronics: The study, control, and application of the conduction of ELECTRICITY through gases or vacuum, or through semiconducting or conducting materials. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Neural Prostheses: Medical devices which substitute for a nervous system function by electrically stimulating the nerves directly and monitoring the response to the electrical stimulation.Electrolysis: Destruction by passage of a galvanic electric current, as in disintegration of a chemical compound in solution.Glass: Hard, amorphous, brittle, inorganic, usually transparent, polymerous silicate of basic oxides, usually potassium or sodium. It is used in the form of hard sheets, vessels, tubing, fibers, ceramics, beads, etc.Visual Prosthesis: Artificial device such as an externally-worn camera attached to a stimulator on the RETINA, OPTIC NERVE, or VISUAL CORTEX, intended to restore or amplify vision.Loudness Perception: The perceived attribute of a sound which corresponds to the physical attribute of intensity.Flow Injection Analysis: The analysis of a chemical substance by inserting a sample into a carrier stream of reagent using a sample injection valve that propels the sample downstream where mixing occurs in a coiled tube, then passes into a flow-through detector and a recorder or other data handling device.Evoked Potentials: Electrical responses recorded from nerve, muscle, SENSORY RECEPTOR, or area of the CENTRAL NERVOUS SYSTEM following stimulation. They range from less than a microvolt to several microvolts. The evoked potential can be auditory (EVOKED POTENTIALS, AUDITORY), somatosensory (EVOKED POTENTIALS, SOMATOSENSORY), visual (EVOKED POTENTIALS, VISUAL), or motor (EVOKED POTENTIALS, MOTOR), or other modalities that have been reported.Hydrogen-Ion Concentration: The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Polarography: An electrochemical technique for measuring the current that flows in solution as a function of an applied voltage. The observed polarographic wave, resulting from the electrochemical response, depends on the way voltage is applied (linear sweep or differential pulse) and the type of electrode used. Usually a mercury drop electrode is used.Membranes, Artificial: Artificially produced membranes, such as semipermeable membranes used in artificial kidney dialysis (RENAL DIALYSIS), monomolecular and bimolecular membranes used as models to simulate biological CELL MEMBRANES. These membranes are also used in the process of GUIDED TISSUE REGENERATION.Electronics, Medical: The research and development of ELECTRICAL EQUIPMENT AND SUPPLIES for such medical applications as diagnosis, therapy, research, anesthesia control, cardiac control, and surgery. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Deafness: A general term for the complete loss of the ability to hear from both ears.Limit of Detection: Concentration or quantity that is derived from the smallest measure that can be detected with reasonable certainty for a given analytical procedure.Electroplating: Coating with a metal or alloy by electrolysis.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Oxidation-Reduction: A chemical reaction in which an electron is transferred from one molecule to another. The electron-donating molecule is the reducing agent or reductant; the electron-accepting molecule is the oxidizing agent or oxidant. Reducing and oxidizing agents function as conjugate reductant-oxidant pairs or redox pairs (Lehninger, Principles of Biochemistry, 1982, p471).Stereotaxic Techniques: Techniques used mostly during brain surgery which use a system of three-dimensional coordinates to locate the site to be operated on.Silver: Silver. An element with the atomic symbol Ag, atomic number 47, and atomic weight 107.87. It is a soft metal that is used medically in surgical instruments, dental prostheses, and alloys. Long-continued use of silver salts can lead to a form of poisoning known as ARGYRIA.Electric Conductivity: The ability of a substrate to allow the passage of ELECTRONS.Catheter Ablation: Removal of tissue with electrical current delivered via electrodes positioned at the distal end of a catheter. Energy sources are commonly direct current (DC-shock) or alternating current at radiofrequencies (usually 750 kHz). The technique is used most often to ablate the AV junction and/or accessory pathways in order to interrupt AV conduction and produce AV block in the treatment of various tachyarrhythmias.Iridium: A metallic element with the atomic symbol Ir, atomic number 77, and atomic weight 192.22.Cats: The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)Membrane Potentials: The voltage differences across a membrane. For cellular membranes they are computed by subtracting the voltage measured outside the membrane from the voltage measured inside the membrane. They result from differences of inside versus outside concentration of potassium, sodium, chloride, and other ions across cells' or ORGANELLES membranes. For excitable cells, the resting membrane potentials range between -30 and -100 millivolts. Physical, chemical, or electrical stimuli can make a membrane potential more negative (hyperpolarization), or less negative (depolarization).Electrophoresis, Microchip: A highly miniaturized version of ELECTROPHORESIS performed in a microfluidic device.Electric Power Supplies: Devices that control the supply of electric current for running electrical equipment.Electroporation: A technique in which electric pulses of intensity in kilovolts per centimeter and of microsecond-to-millisecond duration cause a temporary loss of the semipermeability of CELL MEMBRANES, thus leading to ion leakage, escape of metabolites, and increased uptake by cells of drugs, molecular probes, and DNA.Dogs: The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)Surface Properties: Characteristics or attributes of the outer boundaries of objects, including molecules.Evoked Potentials, Auditory: The electric response evoked in the CEREBRAL CORTEX by ACOUSTIC STIMULATION or stimulation of the AUDITORY PATHWAYS.Neurophysiology: The scientific discipline concerned with the physiology of the nervous system.Polymers: Compounds formed by the joining of smaller, usually repeating, units linked by covalent bonds. These compounds often form large macromolecules (e.g., BIOPOLYMERS; PLASTICS).Subthalamic Nucleus: Lens-shaped structure on the inner aspect of the INTERNAL CAPSULE. The SUBTHALAMIC NUCLEUS and pathways traversing this region are concerned with the integration of somatic motor function.Reproducibility of Results: The statistical reproducibility of measurements (often in a clinical context), including the testing of instrumentation or techniques to obtain reproducible results. The concept includes reproducibility of physiological measurements, which may be used to develop rules to assess probability or prognosis, or response to a stimulus; reproducibility of occurrence of a condition; and reproducibility of experimental results.Nanowires: Nanometer-scale wires made of materials that conduct electricity. They can be coated with molecules such as antibodies that will bind to proteins and other substances.Diamond: Diamond. A crystalline form of carbon that occurs as hard, colorless or tinted isomeric crystals. It is used as a precious stone, for cutting glass, and as bearings for delicate mechanisms. (From Grant & Hackh's Chemical Dictionary, 5th ed)Neurons: The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.Electrochemotherapy: A treatment modality that uses pulsed electrical currents to permeabilize cell membranes (ELECTROPORATION) and thereby enhance the uptake of chemotherapeutic agents, vaccines, or genes into the body's cells.Solar Energy: Energy transmitted from the sun in the form of electromagnetic radiation.Correction of Hearing Impairment: Procedures for correcting HEARING DISORDERS.Cochlea: The part of the inner ear (LABYRINTH) that is concerned with hearing. It forms the anterior part of the labyrinth, as a snail-like structure that is situated almost horizontally anterior to the VESTIBULAR LABYRINTH.Epilepsy: A disorder characterized by recurrent episodes of paroxysmal brain dysfunction due to a sudden, disorderly, and excessive neuronal discharge. Epilepsy classification systems are generally based upon: (1) clinical features of the seizure episodes (e.g., motor seizure), (2) etiology (e.g., post-traumatic), (3) anatomic site of seizure origin (e.g., frontal lobe seizure), (4) tendency to spread to other structures in the brain, and (5) temporal patterns (e.g., nocturnal epilepsy). (From Adams et al., Principles of Neurology, 6th ed, p313)Heart Conduction System: An impulse-conducting system composed of modified cardiac muscle, having the power of spontaneous rhythmicity and conduction more highly developed than the rest of the heart.Cardiac Pacing, Artificial: Regulation of the rate of contraction of the heart muscles by an artificial pacemaker.Temporal Bone: Either of a pair of compound bones forming the lateral (left and right) surfaces and base of the skull which contains the organs of hearing. It is a large bone formed by the fusion of parts: the squamous (the flattened anterior-superior part), the tympanic (the curved anterior-inferior part), the mastoid (the irregular posterior portion), and the petrous (the part at the base of the skull).Finite Element Analysis: A computer based method of simulating or analyzing the behavior of structures or components.Transistors, Electronic: Electrical devices that are composed of semiconductor material, with at least three connections to an external electronic circuit. They are used to amplify electrical signals, detect signals, or as switches.Neural Conduction: The propagation of the NERVE IMPULSE along the nerve away from the site of an excitation stimulus.Auditory Threshold: The audibility limit of discriminating sound intensity and pitch.Indicators and Reagents: Substances used for the detection, identification, analysis, etc. of chemical, biological, or pathologic processes or conditions. Indicators are substances that change in physical appearance, e.g., color, at or approaching the endpoint of a chemical titration, e.g., on the passage between acidity and alkalinity. Reagents are substances used for the detection or determination of another substance by chemical or microscopical means, especially analysis. Types of reagents are precipitants, solvents, oxidizers, reducers, fluxes, and colorimetric reagents. (From Grant & Hackh's Chemical Dictionary, 5th ed, p301, p499)Acoustic Stimulation: Use of sound to elicit a response in the nervous system.Prostheses and Implants: Artificial substitutes for body parts, and materials inserted into tissue for functional, cosmetic, or therapeutic purposes. Prostheses can be functional, as in the case of artificial arms and legs, or cosmetic, as in the case of an artificial eye. Implants, all surgically inserted or grafted into the body, tend to be used therapeutically. IMPLANTS, EXPERIMENTAL is available for those used experimentally.Pacemaker, Artificial: A device designed to stimulate, by electric impulses, contraction of the heart muscles. It may be temporary (external) or permanent (internal or internal-external).Electric Capacitance: The ability of a substrate to retain an electrical charge.Evoked Potentials, Visual: The electric response evoked in the cerebral cortex by visual stimulation or stimulation of the visual pathways.Brain Mapping: Imaging techniques used to colocalize sites of brain functions or physiological activity with brain structures.Psychoacoustics: The science pertaining to the interrelationship of psychologic phenomena and the individual's response to the physical properties of sound.Artifacts: Any visible result of a procedure which is caused by the procedure itself and not by the entity being analyzed. Common examples include histological structures introduced by tissue processing, radiographic images of structures that are not naturally present in living tissue, and products of chemical reactions that occur during analysis.Geobacter: A genus of gram-negative, anaerobic, metal-reducing bacteria in the family Geobacteraceae. They have the ability to oxidize a variety of organic compounds, including AROMATIC HYDROCARBONS.Iontophoresis: Therapeutic introduction of ions of soluble salts into tissues by means of electric current. In medical literature it is commonly used to indicate the process of increasing the penetration of drugs into surface tissues by the application of electric current. It has nothing to do with ION EXCHANGE; AIR IONIZATION nor PHONOPHORESIS, none of which requires current.Electromagnetic Fields: Fields representing the joint interplay of electric and magnetic forces.Models, Neurological: Theoretical representations that simulate the behavior or activity of the neurological system, processes or phenomena; includes the use of mathematical equations, computers, and other electronic equipment.Reaction Time: The time from the onset of a stimulus until a response is observed.Transcutaneous Electric Nerve Stimulation: The use of specifically placed small electrodes to deliver electrical impulses across the SKIN to relieve PAIN. It is used less frequently to produce ANESTHESIA.Nanotechnology: The development and use of techniques to study physical phenomena and construct structures in the nanoscale size range or smaller.

Blockade of hippocampal long-term potentiation by sustained tetanic stimulation near the recording site. (1/3000)

Specific patterns of electrical stimulation trigger several forms of synaptic plasticity in hippocampal pyramidal cells, including a long-term potentiation (LTP) of excitatory synaptic transmission. I investigated the effect of commonly used stimulation protocols at different distances from the recording site. Sustained electrical stimulation (100 Hz, 1 s) delivered close to the recording site prevented LTP induction; the same stimulation from a second electrode placed farther away subsequently produced LTP at the same recording site. Strong stimulation near the recording site could also interfere with LTP triggered from a distal site. In contrast to sustained high-frequency stimulation, intermittent stimulation (theta burst pattern) delivered close to the recording site produced normal LTP. These data support the hypothesis that strong stimulation releases a factor that acts locally to prevent LTP.  (+info)

LocaLisa: new technique for real-time 3-dimensional localization of regular intracardiac electrodes. (2/3000)

BACKGROUND: Estimation of the 3-dimensional (3D) position of ablation electrodes from fluoroscopic images is inadequate if a systematic lesion pattern is required in the treatment of complex arrhythmogenic substrates. METHODS AND RESULTS: We developed a new technique for online 3D localization of intracardiac electrodes. Regular catheter electrodes are used as sensors for a high-frequency transthoracic electrical field, which is applied via standard skin electrodes. We investigated localization accuracy within the right atrium, right ventricle, and left ventricle by comparing measured and true interelectrode distances of a decapolar catheter. Long-term stability was analyzed by localization of the most proximal His bundle before and after slow pathway ablation. Electrogram recordings were unaffected by the applied electrical field. Localization data from 3 catheter positions, widely distributed within the right atrium, right ventricle, or left ventricle, were analyzed in 10 patients per group. The relationship between measured and true electrode positions was highly linear, with an average correlation coefficient of 0.996, 0.997, and 0.999 for the right atrium, right ventricle, and left ventricle, respectively. Localization accuracy was better than 2 mm, with an additional scaling error of 8% to 14%. After 2 hours, localization of the proximal His bundle was reproducible within 1.4+/-1.1 mm. CONCLUSIONS: This new technique enables accurate and reproducible real-time localization of electrode positions in cardiac mapping and ablation procedures. Its application does not distort the quality of electrograms and can be applied to any electrode catheter.  (+info)

Synchronization of local neural networks in the somatosensory cortex: A comparison of stationary and moving stimuli. (3/3000)

Spontaneous and stimulus-induced responses were recorded from neighboring groups of neurons by an array of electrodes in the primary (SI) somatosensory cortex of intact, halothane-anesthetized cats. Cross-correlation analysis was used to characterize the coordination of spontaneous activity and the responses to peripheral stimulation with moving or stationary air jets. Although synchronization was detected in only 10% (88 of 880) of the pairs of single neurons that were recorded, cross-correlation analysis of multiunit responses revealed significant levels of synchronization in 64% of the 123 recorded electrode pairs. Compared with spontaneous activity, both stationary and moving air jets caused substantial increases in the rate, proportion, and temporal precision of synchronized activity in local regions of SI cortex. Among populations of neurons that were synchronized by both types of air-jet stimulation, the mean rate of synchronized activity was significantly higher during moving air-jet stimulation than during stationary air-jet stimulation. Moving air jets also produced significantly higher correlation coefficients than stationary air jets in the raw cross-correlograms (CCGs) but not in the shift-corrected CCGs. The incidence and rate of stimulus-induced synchronization varied with the distance separating the recording sites. For sites separated by /=500 microm, only 37% of the multiunit responses were synchronized by discrete stimulation with a single air jet. Measurements of the multiunit CCG peak half-widths showed that the correlated activity produced by moving air jets had slightly less temporal variability than that produced by stationary air jets. These results indicate that moving stimuli produce greater levels of synchronization than stationary stimuli among local groups of SI neurons and suggest that neuronal synchronization may supplement the changes in firing rate which code intensity and other attributes of a cutaneous stimulus.  (+info)

Effect of biphasic shock duration on defibrillation threshold with different electrode configurations and phase 2 capacitances: prediction by upper-limit-of-vulnerability determination. (4/3000)

BACKGROUND: The defibrillation threshold (DFT) may be affected by biphasic shock duration (BSD), electrode configuration, and capacitance. The upper limit of vulnerability (ULV) may be used to estimate the DFT. For different lead configurations and phase 2 capacitances, we investigated in 18 pigs whether the use of ULV may predict waveforms with lowest DFT. METHODS AND RESULTS: -DFT and ULV were determined by up-down protocols for 10 BSDs. ULVs were measured by T-wave scanning during ventricular pacing (cycle length 500 ms). In protocol 1 (n=6), a pectoral "active can" was combined with an electrode in the superior vena cava as common cathode and a right ventricle electrode as anode (AC+SVC). In protocol 2 and protocol 3 (n=6 each), only the "active can" was used as proximal electrode (AC). Capacitance was 150 microF during both phases in protocol 1 and protocol 3 but 150 microF (phase 1) and 300 microF (phase 2) in protocol 2. ULV and DFT demonstrated a linear correlation in each protocol (r=0.78 to 0.84). Lowest DFTs were found at 10 ms for AC+SVC and at 14 ms for AC (P<0.001). At optimal BSDs, voltage DFTs did not differ significantly between AC (527+/-57 V) and AC+SVC (520+/-70 V). Switching capacitors for phase 2 in a way that reduced leading-edge voltage by 50% while doubling capacity did not change BSD for optimal voltage DFT but increased minimum DFT from 527+/-57 V to 653+/-133 V (P=0.04). CONCLUSIONS: The BSD with lowest DFT is shorter for AC+SVC than for AC. There is no significant difference in voltage DFT between both at optimal BSD. A lower phase 2 capacitance reduces DFTs irrespective of BSD. Because strength-duration curves for DFT and ULV correlate for different BSDs, lead systems, and phase 2 capacitances, ULV determination may allow the prediction of waveforms with lowest DFT.  (+info)

Chronic lithium treatment inhibits amiloride-sensitive sodium transport in the rat distal nephron. (5/3000)

Chronic treatment of rats with lithium leads to Na+ loss and a reduced antinatriuretic response to aldosterone, suggesting that lithium reduces conductive Na+ transport in the distal nephron. This was investigated in the present study by measuring the renal response to aldosterone infusion followed by amiloride in chronically instrumented conscious rats given lithium for 3 to 4 weeks to achieve plasma Li+ concentrations of approximately 0.5 mM. A servo-controlled infusion system was used to maintain sodium and water homeostasis, thereby preventing misinterpretation of the findings as a consequence of drug-induced changes in Na+ balance. In a control group of rats, Na+ excretion decreased in response to aldosterone (p <.01) and subsequent amiloride administration led to a marked increase in Na+ excretion (p <.001). In contrast, in the lithium-treated group, there was no significant response to either aldosterone or amiloride. It is concluded that long-term treatment with lithium, even when plasma Li+ concentrations are below 1 mM, reduces aldosterone-stimulated Na+ transport through the amiloride-sensitive Na+ channels in the principal cells of the distal nephron.  (+info)

Mapping of atrial activation with a noncontact, multielectrode catheter in dogs. (6/3000)

BACKGROUND: Endocardial mapping of sustained arrhythmias has traditionally been performed with a roving diagnostic catheter. Although this approach is adequate for many tachyarrhythmias, it has limitations. The purpose of this study was to evaluate a novel noncontact mapping system for assessing atrial tachyarrhythmias. METHODS AND RESULTS: The mapping system consists of a 9F multielectrode-array balloon catheter that has 64 active electrodes and ring electrodes for emitting a locator signal. The locator signal was used to construct a 3-dimensional right atrial map; it was independently validated and was highly accurate. Virtual electrograms were calculated at 3360 endocardial sites in the right atrium. We evaluated right atrial activation by positioning the balloon catheter in the mid right atrium via a femoral venous approach. Experiments were performed on 12 normal mongrel dogs. The mean correlation coefficient between contact and virtual electrograms was 0.80+/-0.12 during sinus rhythm. Fifty episodes of atrial flutter induced in 11 animals were evaluated. In the majority of experiments, complete or almost complete reentrant circuits could be identified within the right atrium. Mean correlation coefficient between virtual and contact electrograms was 0.85+/-0.17 in atrial flutter. One hundred fifty-six episodes of pacing-induced atrial fibrillation were evaluated in 11 animals. Several distinct patterns of right atrial activation were seen, including single-activation wave fronts and multiple simultaneous-activation wave fronts. Mean correlation coefficient between virtual and contact electrograms during atrial fibrillation was 0.81+/-0.18. The accuracy of electrogram reconstruction was lower at sites >4.0 cm from the balloon center and at sites with a high spatial complexity of electrical activation. CONCLUSIONS: This novel noncontact mapping system can evaluate conduction patterns during sinus rhythm, demonstrate reentry during atrial flutter, and describe right atrial activation during atrial fibrillation. The accuracy of electrogram reconstruction was good at sites <4.0 cm from the balloon center, and thus the system has the ability to perform high-resolution multisite mapping of atrial tachyarrhythmias in vivo.  (+info)

Intraoperative monitoring during surgery for acoustic neuroma: benefits of an extratympanic intrameatal electrode. (7/3000)

OBJECTIVES: To assess the utility of an extratympanic intrameatal electrode for intraoperative monitoring during acoustic neuroma and other cerebellopontine angle tumour surgery and to define the neurophysiological and surgical factors which influence hearing preservation. METHODS: Twenty two patients, 18 with acoustic neuromas and four with other cerebellopontine angle tumours, underwent intraoperative monitoring during tumour excision. The extratympanic intrameatal electrode (IME) was used to record the electrocochleogram (ECoG) and surface electrodes to record the brainstem auditory evoked response (ABR). RESULTS: The compound action potential (CAP) of the ECoG was two and a half times greater in amplitude than wave I of the ABR and was easily monitored. Virtually instant information was available as minimal averaging was required. Continuous monitoring was possible from the commencement of anaesthesia to skin closure. The IME was easy to place, non-invasive, and did not interfere with the operative field. Operative procedures which affected CAP or wave V latency or amplitude were drilling around the internal auditory meatus, tumour dissection, nerve section, and brainstem and cerebellar retraction. Hearing was achieved in 59% of patients. CONCLUSIONS: The IME had significant benefits in comparison with other methods of monitoring. The technique provided information beneficial to preservation of hearing.  (+info)

Non-invasive determination of bacterial single cell properties by electrorotation. (8/3000)

So far, electrorotation and its application to the determination of single cell properties have been limited to eukaryotes. Here an experimental system is described that allows the recording of electrorotation spectra of single bacterial cells. The small physical dimensions of the developed measuring chamber combined with a single frame video analysis made it possible to monitor the rotation of objects as small as bacteria by microscopical observation despite Brownian rotation and cellular movement. Thus physical properties of distinct organelles of E. coli could be simultaneously determined in vivo at frequencies between 1 kHz and 1 GHz. Experimental data were evaluated following a three-shell model of the cell. Electrical conductivities of cytoplasm and outer membrane were determined to 4.4 mS/cm and 25 microS/cm, respectively, that of the periplasmic space was found to increase with the square root of the medium ionic strength. Specific capacitances of inner and outer membrane amounted to 1.4 microF/cm2 and 0.26 microF/cm2, respectively, the thickness of the periplasm to about 50 nm. Heat treatment of the cells lead to a reduction of cytoplasmic conductivity to 0.9 mS/cm, probably caused by an efflux of ions through the permeabilized inner membrane.  (+info)

A pacemaker system includes an electrode lead having a distal tip electrode for supplying stimulation pulses to cardiac tissue and a ring electrode, the electrode lead being connected to a cardiac stimulator. A detector is contained in a stimulator housing and is connected to the electrode lead for detecting electrical cardiac activity between said ring electrode and said tip electrode. Measurement of a signal dependent on physical activity of the subject in whom the pacemaker is implanted is obtained either by applying a voltage on the ring electrode during a predetermined measuring period and measuring a current through the ring electrode during at least a part of this period, or by, after detection of a QRS wave, applying a potential on the ring electrode and measuring the current between the housing and the ring electrode during the measuring period and also applying an alternating current between the tip electrode and the housing and measuring a voltage difference between the tip electrode and the
An electrochemical sensor based on a three-electrode method containing a reference electrode, comprising: A working electrode 2, a counter electrode 3 and a reference electrode 4 formed on an insulating substrate 1; an examining electrode 8 provided to examine an electric potential of the reference electrode 4; a combining layer 20, an immobilized enzyme layer 21 and a diffusion-limiting layer 22 made of a fluororesin provided on voltmeter is provided on these electrodes, between the examining electrode 8 and the reference electrode 4 so that the electric potential of the reference electrode can be examined; to detect an abnormality in the reference electrode immediately after its occurrence, recover a high reliability of measured value by removing the abnormality quickly, make it possible to conduct a continuous measurement for a long time and furthermore try to reduce a running cost.
A removable medical electrode system for monitoring electrical activity of selected tissue comprises a flexible member (22) of electrically insulating material shaped to conform to a surface of the tissue (20). It includes a mechanism (32, 34) for articulating the electrode (10) between an expanded and contracted position to place and remove the electrode (10) on the tissue (20), and to hold the electrode (10) in place during an operation. An electrical conductor (42) is fixed to the electrode (10) to carry electrical impulse signals from the nerve tissue (20) to a monitoring system.
ValuTrode Electrodes - Get the best prices on dura-stick electrodes, dynapak electrodes, iontophoresis devices electrodes, lead wires accessories, pals platinum electrodes, silver electrodes, sponge electrodes, uni-patch electrodes and valutrode electrodes including valutrode white foam top electrodes - 1-14in round, valutrode white fabric top electrodes 2in 2in square, valutrode white foam top electrode - 2in 2in square, valutrode white fabric top electrodes - 2in round, valutrode white fabric foam electrodes - 3 in. 5 in. rectangle, valutrode white fabric top electrodes - 1.5in 2.5in oval, valutrode white fabric top electrode - 3in 5in rectangle, valutrode white fabric top electrode - 1.5in 2.5in oval, white fabric round foam electrodes, valutrode white fabric top electrodes - 3in round, valutrode white fabric top electrode - 2in 4in oval and white fabric back electrodes - 4in 7in rectangle online at Medical Supplies & Equipment.
0138]However, the electrode combination can be shifted distally, i.e., upward in the orientation of FIG. 7. There is room on leads 26A, 26B to shift the electrode combination distally by two shift positions. Hence, if the initial position is shift position 1, shifts can be made to shift position 2 and shift position 3. Each shift may represent a shift in the position of the active electrodes associated with the previous electrode combination such that the electrical stimulation pattern remains identical or substantially similar, e.g., in terms of relative positions and spacing between the active electrodes in both the initial and shifted electrode combination. In addition, the initial and shifted electrode combinations have a common number of electrodes. In the example of FIG. 7, each electrode combination has three electrodes (110C, 110D, and 112C for the first combination), and the electrode combinations have a substantially similar electrode pattern. Active electrodes are those electrodes ...
The present invention relates generally to systems and methods for electrochemical sensing. Particularly, the invention relates to optimizing bias settings in an electrode system to increase oxygen pr
In this study, a sodalite nanozeolite was synthesized and characterized by X-ray diffraction (XRD) and scanning electronic microscopy (SEM). Following the morphology evolution of the sodalite nanozeolite in the SEM images illustrates the formation of the spherical particle with a size between 60 and 80 nm. Then, carbon paste electrode (CPE) was modified by sodalite nanozeolite and Ni2+ ions. The electrocatalytic performance of the fabricated electrode (Ni-SOD/CPE) towards glucose oxidation were evaluated by cyclic voltammetry and Chronoamperometry and it was used as anode for the electrocatalytic oxidation of glucose in 0.1 M of NaOH solution. Also, the electron transfer coefficient, the diffusion coefficient and the mean value of catalytic rate constant for glucose and redox sites of electrode were found to be 0.86, 3.13×10−5 cm2 s−1 and 5.34×106 cm3 mol−1 s−1, respectively. Good catalytic activity, high sensitivity, good choice and the stability and easy preparation enables the modified
... The MyoTrac Muscle Monitor ships with a starter package of 3 Triode electrodes. If you want to use a different electrode configuration than the Triode Electrode Pad provides, you can order an Extender Cable.. In order to allow bilateral placement on the same muscle group an Extender Cable (available in lengths of 40" or 21") is available. This extender cable plugs into the end of the Triode Electrode head that ships with the MyoTrac and allows a strip of 3 electrodes to be used together for a Frontalis placement or separated for placements on other muscles bilaterally (such as the temporalis, masseter, trapezius, etc. muscle groups).. We have created a series of illustrations to clarify the process preparing the electrodes for placement. Both the Triode Electrode Pads and the Strip of 3 Electrodes are available in packages of 100. They both feature hypoallergenic adhesive surfaces and silver chloride electrodes that do not need gel applied. Both types of electrodes ...
article{e3604934-e3c4-4e2c-8fa9-23566d3e0157, abstract = {The role of the electrode material in the efficiency of direct (non-mediated) bioelectrocatalytic reduction of H2O2, catalyzed by horseradish peroxidase (HRP) is studied and discussed. The variations in direct peroxidase bioelectrocatalysis when coming from carbon/graphite to metal electrodes and oxides, as well as modified electrodes, are analyzed regarding the variations in adsorption/orientation of peroxidase at the electrodes, interfacial electron transfer rates and mechanism of catalysis.}, author = {Ferapontova, Elena}, issn = {1040-0397}, keyword = {Modified electrodes,Silver,Gold,Graphite,Horseradish peroxidase,Bioelectrocatalysis}, language = {eng}, number = {13-14}, pages = {1101--1112}, publisher = {John Wiley & Sons}, series = {Electroanalysis}, title = {Direct peroxidase bioelectrocatalysis on a variety of electrode materials}, url = {http://dx.doi.org/10.1002/elan.200403003}, volume = {16}, year = {2004 ...
A highly reliable biosensor is provided which is reduced in influences of any interfering substance or preexisting oxygen in a sample solution. The biosensor comprises an electrode system including a working electrode, a counter electrode and a third electrode also usable as an interfering substance detecting electrode, a reagent layer containing at least an oxidoreductase and an electron mediator, and an electrically insulating base plate for supporting the electrode system and the reagent layer, wherein the third electrode is arranged at an opposing position to that of at least one of the working electrode and the counter electrode and the reagent layer is arranged at a predetermined position apart from the third electrode.
Abstract The electrochemical response of serotonin on the modified electrode based on multiwalled-carbon-nanotube (MWCNT) doped respectively with nickel, zinc and iron oxide nanoparticles coating on glassy carbon electrode (GCE) at physiological pH7 was determined using cyclic voltammetry (CV) and square wave voltammetry (SWV). The modified GCE/MWCNT-metal oxide electrodes exhibited excellent electrocatalytic activity towards the detection of serotonin at large peak current and lower oxidation potentials compared to other electrodes investigated. The dynamic range for the serotonin determination was between 5.98×10−3 μM to 62.8μM with detection limits 118, 129 and 166nM for GCE/MWCNT-NiO, GCE/MWCNT-ZnO and GCE/MWCNT-Fe3O4 sensors respectively. GCE-MWCNT-NiO was the best electrode in terms of serotonin current response, electrode stability, resistance to fouling and limit of detection towards the analyte. The developed sensors
Definition of electrochemical reaction by Electropedia. Meaning of electrochemical reaction. Translations of electrochemical reaction. Equivalent terms for electrochemical reaction.
A novel glassy carbon electrode (GCE) modified with carbon-spheres has been fabricated through a simple casting procedure. The modified GCE displays high selectivity and excellent electrochemical catalytic activities towards dopamine (DA), serotonin (5-HT), and ascorbic acid (AA). In the co-existence system, the peak separations between AA and DA, DA and 5-HT, and AA and 5-HT are large up to 230, 180, and 410 mV, respectively. Differential pulse voltammetry (DPV) has been employed to simultaneously detect DA, 5-HT, and AA, and the linear calibration curves for DA, 5-HT, and AA are obtained in the range of 20.0-150.0 μM, 40.0-750.0 μM and 300.0-2,000.0 μM with detection limits (S/N = 3) of 2.0 μM, 0.7 μM and 0.6 μM, respectively. The proposed electrode has been applied to detect DA, 5-HT, and AA in real samples using standard addition method with satisfactory results.
Abstract: Stable electrode modified by aminylferrocene/L-cysteine(L-Cys) was fabricated successfully by linking aminylferrocene to L-Cys self-assembled monolayer(SAM) with coupling reagent. The modified electrode exhibits a pair of reversible redox peaks in pH 7.0 phosphate buffer solution. The electrochemical behaviors of the modified electrode were explored in detail with cyclic voltammetry and a.c. impedance. The apparent electron transfer coefficient and standard rate constant were calculated to be 0.66 and 6.86 s-1 for the modified electrode respectively. The modified electrode shows electrocatalytic activity for oxidation of epinephrine (EP) in pH 7.0 phosphate buffer solution. The peak current was proportional to the concentration of EP in the range of 2.0×10-7~1.0×10-5 mol·dm-3. Key words: Aminylferrocene, L-cysteine, Self-assembled monolayer, Electrocatalysis, Epinephrine ...
0013]Now referring to FIGS. 1, 2 and 3, two schematic block diagrams and a simplified circuit diagram of an electrode pair and monitor or monitor input circuit may be seen. The sensing electrode for sensing the bio-electric signal VS may be of a conventional monitoring electrode design or a special electrode design fabricated for this specific purpose. The reference electrode design may also be a conventional reference electrode design, if desired, a single electrode or a composite of several electrodes, as is well known in the art of ECG monitoring. It is preferred that the reference electrode be in contact with the body tissue at a greater distance from the bio-electric tissue of interest than the sensing electrode. It is also preferred that the reference electrodes position be constant or experience less motion (less percent change in distance relative to the tissue generating the bio-electric signal of interest) than the sensing electrode. As shown in FIG. 1, the monitor may be a ...
Precis of the Global Fuel Cell Membrane Electrode Assemblies(MEA) Market 2017 Research Report Explore Professional Survey, Market Professional, and more!. The market research report provides a detailed analysis and data about the Fuel Cell Membrane Electrode Assemblies(MEA) market statistical study, the key players, growth dynamics, and geographical analysis. The report provides the information concerning the factors that impel the growth of the Fuel Cell Membrane Electrode Assemblies(MEA) global industry. The Fuel Cell Membrane Electrode Assemblies(MEA) market constitute of the leading groups which play a vital role in the product sales, manufacturing, production, distribution of the products in order to meet the supply and demand chain. A detailed study of the global market share of the past and the future along with the predictable forecast trends is also mentioned in the present report.. ...
A NEW ELECTROCHEMICAL SENSOR BASED ON MODIFIED CARBON NANOTUBE-GRAPHITE MIXTURE PASTE ELECTRODE FOR VOLTAMMETRIC DETERMINATION OF RESORCINOL
A robust pH sensor from Endress+Hauser can now solve the problem of reference contamination commonly experienced during pH measurement in ultra harsh conditions such as mining slurries and paper & pulp applications.. pH measurement within ultra harsh applications that include high solid content poses several challenges. Because of the harmful ions that defuse into the pH electrode reference system and the high solid content, the potential to disable the electrode by blocking the diaphragm under these extreme conditions is high. The surface area of the pH electrode diaphragm therefore needs to be enlarged to avoid blockage. However this increases the risk of reference contamination as the diaphragm is porous and more harmful ions can now enter the reference system of the pH electrode.. Traditionally, these enlarged diaphragms have been made from wood due to its resistance to contamination, but the wooden diaphragm is relatively thick and slows down the electrodes response time. In most critical ...
An electrochemical impedance technique which measures the impedance between two reference electrodes placed on opposite sides of the working electrode, and which can be used for the determination of the effective conductivity in the pore electrolyte in a porous electrode is presented. Information about the electroactive surface area and kinetic parameters can also be obtained from these measurements. A theoretical expression for the evaluation of the experimental results has been derived and analysed. The high frequency intercept of the impedance curve with the real axis will give the external ohmic resistance for electrode materials with an infinitely high conductivity. Even at very low frequencies, some of the current passing through the electrode will pass through the electrode in the solid material. The relative importance of this transfer of current in the solid phase through the electrode can be determined for the general case by the dimensionless quantity λ, which depends on the ...
The present invention provides a high-performance glucose sensor having excellent storage stability and an improved response characteristic. This sensor comprises: an electrically insulating base plate; an electrode system including at least a working electrode and a counter electrode formed on the base plate; and a reaction layer containing at least pyrrolo-quinoline quinone dependent glucose dehydrogenase, formed in contact with or in the vicinity of the electrode system, and the reaction layer contains at least one kind of additive selected from the group consisting of gluconic acid and salts thereof.
The present invention provides a high-performance glucose sensor having excellent storage stability and an improved response characteristic. This sensor comprises: an electrically insulating base plate; an electrode system including at least a working electrode and a counter electrode formed on the base plate; and a reaction layer containing at least pyrrolo-quinoline quinone dependent glucose dehydrogenase, formed in contact with or in the vicinity of the electrode system, and the reaction layer contains at least one kind of additive selected from the group consisting of gluconic acid and salts thereof.
Cardiology Specialty Multi-Function Electrodes, with a low viscosity gel that provides the best skin coupling, are designed to virtually eliminate dermal damage in special procedure areas of the hospital.. Radiolucent Multi-Function Electrodes are designed to provide an unobstructed view of the coronary arteries during x-ray studies. Available in solid or liquid gel.. Biphasic Multi-Function Electrodes are part of the complete Rectilinear Biphasic™ system -ZOLLs breakthrough technology-proven to achieve superior results in cardioversion of atrial fibrillation. Lower energy levels combined with the unique liquid gel technology virtually eliminate post-procedural dermal damage.. Sterile Multi-Function Electrodes, with a unique two-pouch system that allows placement of the posterior electrode prior to surgery, are optimal for use in the operating room. They are also available with 10-foot (3-meter) lead wires.. Pacing Only Electrodes are long-term pacing electrodes proven to work with ZOLLs ...
A review. The data reported in literature demonstrate that screen-printed carbon electrodes are very suitable for supporting nucleic-acid layers and to transduce effectively the DNA recognition event and many works have been devoted to developing self contained screen-printed DNA chips. In an effort to develop a rapid and efficient scheme for immobilizing nucleic acids onto carbon screen-printed transducers, many authors took advantage of the strong adsorptive accumulation of these biomols. at the screen-printed carbon surfaces. In particular, many of them reported that electrochem. adsorption (adsorption controlled by a pos. potential) enhances the stability of the probe and this technique was preferentially chosen. Thus, this review will focus on an electrochem. genosensor developed using carbon screen-printed electrodes as the transducers; the methods to immobilize DNA probes onto carbon based surfaces will be reviewed and special emphasis will be given to the description of the electrochem. ...
Electrode combinations.Red electrodes are used for current injunction, and green electrodes are used for voltage measurement. The combinations can be divided in
Get the most from your R Series® resuscitation platform with OneStep Electrodes for adults and pediatrics. OneStep Complete Electrodes for adults offer high-current defibrillation and capture CPR quality. These electrodes can also be used for monitoring and for cardioversion, and to deliver constant-current pacing-without the need for a separate three-lead ECG cable.. OneStep Pediatric CPR Electrodes provide the only CPR support for children under 55 pounds, while also enabling defibrillation, pacing, and cardioversion. When pediatric electrodes are attached, the R Series automatically reduces the starting energy to 50 joules to ensure safe defibrillation.. OneStep Electrodes can remain pre-connected, even during a 30-joule shock test, because of a patented dual-circuit design. There is no need to disconnect the electrodes to test the defibrillator, meaning readiness is not compromised.. ...
A defibrillation pulse generator and lead system particularly adapted to allow for implant in a single incision and subcutaneous pocket. The electrode system consists of a right ventricular electrode and a combined, subcutaneously implanted pulse generator housing and flexible periprerally extending electrode. The flexible electrode extends in a generally co-planar relation with respect to the major surfaces of the device housing and may comprise a plurality of electrode segments electrically connected in common with the device housing and distributed over a flexible electrode pad.
METHODS: Stainless steel (SS) electrodes (n=4) were submerged in 37°C +/-0.5°C 1X phosphate buffered saline and incubated over ~200 hours during which EIS and CV were performed 3X daily using a three electrode system. During EIS, a sinusoidal stimulation with amplitude of 10 mV with respect to the open circuit potential was applied at frequencies from 1 Hz to 100 kHz. CV was completed by sweeping the potential on the working electrode from an initial voltage and upper limit of 0.8 V to a lower limit of -0.6 V using a scan rate of 1000 mV/s. The mean CSCc of the four experimental electrodes was then calculated and differences were quantified using a linear regression model. The initial 10 hours of incubation time during testing were excluded from models to focus on long term stability as opposed to initial electrode fluctuations ...
Lithium-ion battery technology remains to be the heart in operating the majority of new commercial mobile devices and electrical vehicles. Thus, even though it is more than 25 years ago Sony introduced the worlds first commercial Li-ion battery, there is still today a demand for cheaper and safer battery materials with higher energy density. In order to meet this demand, an increased fundamental understanding of the detailed structural and microstructural transformations and electrochemical reactions taking place in Li-ion batteries is needed. For this purpose we have developed special capillary-based micro-battery cells allowing diffraction information to be obtained from only the active electrode material during battery operation. We have used the cell to study structural and microstructural changes during battery operation by in situ / operando synchrotron X-ray powder diffraction (XRPD). Operando XRPD studies of both cathode and anode materials will be presented as examples of the ...
Ceramic proton conductors have the potential to become an essential part of future clean energy systems - from fuel cells to steam electrolysers and catalytic membrane reactors. The project gathers world-leading industry (CoorsTek), high research excellence institute (SINTEF) and university (UiO FASE) to develop innovative segmented-in-series proton conducting ceramic cells integrating novel composite glass-ceramic interconnects and nanostructured electrodes for stable operation of highly efficient steam methane reforming reactors. To tackle this ambitious objective, the project builds on the core expertise of the partners and addresses two distinct research activities underpinning the development of these novel reactors: hierarchically porous electrodes with a nanostructured porous network for improved catalytic activity confined in a macroporous network ensuring fast mass transport; and development of an integrated composite interconnect and seal ensuring dual functions of gas tightness and ...
Dealing with complete cells is a lot to think about at once. Chemists recognized this and developed the notion that they could theoretically separate the anode and cathode parts of the cell (impossible in practice, or a complete circuit wouldnt be present). Using this assumption, they could consider only the oxidation or reduction reaction, one at a time. So the concept of an "electrode potential" value was born. The conventional standard conditions mentioned above express this as a "standard electrode potential." Even then, as in all of thermodynamics, chemists cannot readily establish absolute values. All standard electrode potential values are established relative to a "standard hydrogen electrode" (SHE), which is defined as having a potential of 0.000 volts. Students should consult their textbooks for details on the construction of a standard hydrogen electrode. The AP Chemistry Examination is unlikely to address this subject.. For student reference, the AP Chemistry Exam includes a table ...
In this study, Pt-Ir binary electrodes were prepared by DC magnetron sputtering and characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), electrochemical techniques, and CO stripping. The effect of Ir loading in electrocatalytic activity was also explored. It was found that Ir doping up to 80 % resulted in an increase of the electrochemically active surface (EAS) area and better electrocatalytic performance toward methanol electrooxidation reaction (MOR). The above conclusion was confirmed by CO stripping experiments as well as during oxidation of methanol where the electrodes were used as anodes in a one-compartment cell. The electrode with the lower Pt loading (i.e., 20 %) exhibited better electrocatalytic activity than the pure Pt anode. The observed higher performances of Ir loading electrodes were attributed to the enhanced EAS of the Pt-Ir binary electrodes and the electronic interactions between Pt and Ir atoms.. Keywords: Pt-Ir electrodes ; Methanol oxidation ...
It is shown, for the first time, that a bare carbon paste electrode can be used for the simultaneous quantification of anti-inflammatory drugs: naproxen (NPX), diclofenac (DCF) and acetaminophen (ACT) in aqueous media. The analytical features are: 19 ± 7, 4.1 ± 1.9 and 3.7 ± 1.5 μM as detection limits of DCF
An enzyme electrode based on a glass electrode for measuring penicillin-V concentration is described. In preparing this electrode, penicillinase is immobilized by cross-linking with a very fine film of glutaraldehyde, which is sprayed directly over the sensitive end of a pH glass electrode. The penicillin sensor was used for the determination of penicillin-V concentrations in phosphate buffer, fermentation broth and dairy milk, the ranges of concentrations detected being 1.5-15, 2.5-15 and 2-12 mM, respectively. The linearity, stability, sensitivity, reversibility and pH and buffer strength dependence of the electrode were examined and are discussed. An extremely short response time of less than 10 s is obtained with electrodes made in this manner.
Covalent tethering of PPh2NC6H4C [[triple bond, length as m-dash]] CH2 ligands (PPh2NC6H4C [[triple bond, length as m-dash]] CH2 = 1,5-di-(4-ethynylphenyl)-3,7-diphenyl-1,5-diaza-3,7-diphosphacyclooctane) to planar, azide-terminated glassy carbon electrode surfaces has been accomplished using a CuI-catalyzed al... Earth Abundant Element Compounds in Homogeneous Catalysis
Gold (Au) electrodes coated with layer-by-layer (LbL) thin films composed of chitosan (CHI) were prepared to evaluate the redox properties of hexaammine ruthenium ions, Ru(NH3)63+, and ferricyanide ions, Fe(CN)63− LbL films were prepared on an Au electrode by electrostatic LbL deposition using polycationic CHI and poly(vinyl sulfate) (PVS) or poly(acrylic acid) (PAA) as anionic component. Redox peak current in cyclic voltammetry of Ru(NH3)63+ on the CHI/PVS and CHI/PAA film-coated electrodes increased with increasing thickness of the films. Interestingly, the cyclic voltammograms showed two pair of redox peaks, originating from Ru(NH3)63+ diffusing across the LbL layers and from those confined in the film. The results were rationalized in terms of the electrostatic interactions between Ru(NH3)63+ and excess negative charges in the LbL films originating from PVS and PAA. In contrast, Fe(CN)63− was not confined in the LbL films due to electrostatic repulsion of Fe(CN)63− and excess negative charges.
In conventional scalp EEG, the recording is obtained by placing electrodes on the scalp with a conductive gel or paste, usually after preparing the scalp area by light abrasion to reduce impedance due to dead skin cells. Many systems typically use electrodes, each of which is attached to an individual wire. Some systems use caps or nets into which electrodes are embedded; this is particularly common when high-density arrays of electrodes are needed.. Electrode locations and names are specified by the International 10-20 system[38] for most clinical and research applications (except when high-density arrays are used). This system ensures that the naming of electrodes is consistent across laboratories. In most clinical applications, 19 recording electrodes (plus ground and system reference) are used.[39] A smaller number of electrodes are typically used when recording EEG from neonates. Additional electrodes can be added to the standard set-up when a clinical or research application demands ...
A paddle-type electrode or electrode array is implantable like a percutaneously inserted lead, i.e., without requiring major surgery, and once implanted, expands to provide a platform for many electrode configurations. The electrode array is provided on a flexible, foldable, subcarrier or substrate. Such subcarrier or substrate folds or compresses during implantation, thereby facilitating its insertion using percutaneous implantation techniques and tools. Once implanted, such subcarrier or substrate expands, thereby placing the electrodes in a desired spaced-apart positional relationship, and thus achieving a desired electrode array configuration. A steering stylet may be accommodated in a lumen provided in the subcarrier or substrate. Insertion tools useful with such electrode arrays include a needle with an oblong cross-section, which accommodates the dimensions of the folded array, and also accommodates other electrode arrays that are not necessarily folded.
Electrode Materials Ultrafine Nickel Powder with 20nm 40nm 70nm 100nm(id:10008992). View product details of Electrode Materials Ultrafine Nickel Powder with 20nm 40nm 70nm 100nm from SAT Nano Technology Material CO. Ltd. manufacturer in EC21
Create healthcare diagrams like this example called EEG Electrode Placement in minutes with SmartDraw. SmartDraw includes 1000s of professional healthcare and anatomy chart templates that you can modify and make your own.
The present invention provides a sensor head for use in an implantable device that measures the concentration of an analyte in a biological fluid which includes: a non-conductive body; a working electrode, a reference electrode and a counter electrode, wherein the electrodes pass through the non-conductive body forming an electrochemically reactive surface at one location on the body and forming an electronic connection at another location on the body, further wherein the electrochemically reactive surface of the counter electrode is greater than the surface area of the working electrode; and a multi-region membrane affixed to the nonconductive body and covering the working electrode, reference electrode and counter electrode. In addition, the present invention provides an implantable device including at least one of the sensor heads of the invention and methods of monitoring glucose levels in a host utilizing the implantable device of the invention.
An electrochemical cell includes a fuel electrode configured to operate as an anode to oxidize a fuel when connected to a load, and configured to operate as a cathode when connected to a power supply. The fuel electrode comprises a plurality of scaffolded electrode bodies, wherein the scaffolded electrode bodies are of varying size. The electrode bodies are of a larger size at positions distal from a charging electrode configured to act as an anode when connected to the power supply, and of a smaller size at positions proximal to the charging electrode. When connected to a load, the scaffolded electrode bodies-containing fuel electrode acts as the electrochemical cell anode and electrodeposited fuel is oxidized.
An approach for implementing a subcutaneous medical electrode system involves positioning a number of electrode subsystems in relation to a heart so that a majority of ventricular tissue is included within a volume defined between the electrode subsystems. One of the electrode subsystems so positioned may include a can electrode located on a housing enclosing a medical device. The medical device may be configured to provide therapeutic, diagnostic, or monitoring functions, including, for example, cardiac arrhythmia therapy.
Sensitive determination of metronidazole based on Graphene-TiO2 modified glassy carbon electrode in human serum and urine samples
Looking for the webs Top EEG Electrodes Sites? Top20Sites.com is the leading directory of popular Electrodes, EKG Electrodes, EEG Electrodes, & Biomedical Instrumentation sites.
Page contains details about CuONP-CS composite-modified glassy carbon electrode . It has composition images, properties, Characterization methods, synthesis, applications and reference articles : nano.nature.com
Metallophthalocyanines confined on the surface of electrodes are active catalysts for a large variety of electrochemical reactions and electrode surfaces modified by these complexes can be obtained by simple adsorption on graphite and carbon. However, more stable electrodes can be achieved by coating their surfaces with electropolymerized layers of the complexes, that show similar activity than their monomer counterparts. In all cases, fundamental studies carried out with adsorbed layers of these complexes have shown that the redox potential is a very good reactivity index for predicting the catalytic activity of the complexes. Volcano-shaped correlations have been found between the electrocatalytic activity (as log I at constant E) versus the Co(II)/(I) formal potential (E°′) of Co-macrocyclics for the oxidation of several thiols, hydrazine and glucose. For the electroreduction of O2 only linear correlations between the electrocatalytic activity versus the M(III)/M(II) formal potential have ...
To simulate the electrode we add a small section to serve as the electrode resistance and capacitance */ /* watch out when changing Ra in the model since this electrode.Ra is used for the series resistance! */ begintemplate Electrode public electrode create electrode // c (pf) = cm*area = PI*L*diam*(.01) * cm // rs (MOhm) = Ra*L/2 / (PI*diam^2/4) = 2*L/PI/diam^2 * (.01) * Ra // so it is nice to have // PI*L*diam*.01 = 1 // 2*L/PI/diam^2*.01 = 1 // diam = (2/PI^2)^(1/3) // L = 1/.01/PI/diam proc init_electrode() { electrode { diam = (2/PI^2)^(1/3) L = 1/.01/PI/diam insert pas g_pas = 0 e_pas = 0 } } proc init() { init_electrode() electrode Ra = 0.001 //(Ohm*cm) electrode cm = 0 //(uF/cm2) connect electrode(0), $1 } //electrode makeppm() endtemplate Electrode objref se,pe,te soma se=new Electrode(0.5) priden[0] pe=new Electrode(1) se.electrode.Ra = 1.2 se.electrode.cm = 1e-6 pe.electrode.Ra = 17.5 pe.electrode.cm = 2.95 access soma tstop=15 ...
A surgical apparatus for delivering a conductive fluid to a target site for subsequent formation of a virtual electrode to ablate bodily tissue at the target site by applying a current to the delivered conductive fluid. The surgical apparatus includes an elongated device forming a helical needle. The helical needle is configured to engage bodily tissue and is hollow for delivering conductive fluid from a fluid source. Finally, the helical needle terminates in a needle tip. In one preferred embodiment, an electrode is associated with the helical needle for applying a current to conductive fluid delivered from the helical needle. During use, following delivery of conductive fluid, the electrode applies a current to the delivered conductive fluid for creating a virtual electrode. The virtual electrode ablates bodily tissue contacted by the conductive fluid.
In this schematic representation of the galvanic cell, one will note the symmetry between the left and the right members as seen from the center of the row occupied by the "Test Solution" (the solution whose pH must be measured). In other words, the glass membrane and the ceramic junction occupies both the same relative place in each respective electrode (indicative (sensing) electrode or reference electrode). The double "pipe symbol" (,,) indicates a diffusive barrier that prevents (glass membrane), or slowing down (ceramic junction), the mixing of the different solutions. By using the same electrodes on the left and right, any potentials generated at the interfaces cancel each other (in principle), resulting in the system voltage being dependent only on the interaction of the glass membrane and the test solution. The measuring part of the electrode, the glass bulb on the bottom, is coated both inside and out with a ~10 nm layer of a hydrated gel. These two layers are separated by a layer of ...
Electrochemical behaviour of some alkaloids, namely: caffeine, aminophylline, theophylline, codeine phosphate and papaverine hydrochloride, that are in solution in various combinations or in the presence of other compounds contained in pharmaceuticals or in real samples (urine) was investigated using cyclic voltammetry (CV), square-wave voltammetry (SWV) and differential pulse voltammetry (DPV) on electrochemically activated glassy carbon electrode. [...] The proposed electroanalytical methods were successfully applied in the simultaneous determination of these alkaloids in different combination or in the presence of other compounds. The great part of these combinations can be analyzed simultaneously because they practically do not interfere. The electrochemical test methods attempted to detect the presence of alkaloids in urine samples collected from subjects who consumed coffee (caffeine), and from a patient under treatment with Miofilin® (aminophylline). Urine samples were determined after ...
Standard electrode potentials (reduction potentials)[edit]. Each half-reaction has a standard electrode potential (E0. cell), ... The battery is made out of a zinc electrode in a ZnSO4 solution connected with a wire and a porous disk to a copper electrode ... and the anode is a standard hydrogen electrode where hydrogen is oxidized: ​1⁄2 H2 → H+ + e−.. The electrode potential of each ... Electrode potential values from: Petrucci, Ralph H.; Harwood, William S.; Herring, F. Geoffrey (2002). General chemistry: ...
DEP-well electrodes[edit]. These electrodes were developed [37] to offer a high-throughput yet low-cost alternative to ... Electrode geometries[edit]. At the start, electrodes were made mainly from wires or metal sheets. Nowadays, the electric field ... This electrode geometry showed that the electrical field was highest at the middle of the inter-electrode gaps.[35] ... These small electrodes allow the handling of small bioparticles. The most used electrode geometries are isometric, polynomial, ...
Dry-contact electrode ear-EEG[edit]. Dry-contact electrode ear-EEG is a method in which no gel is applied between the electrode ... the mechanical design of the electrode, the surface properties of the electrode, and how the electrode is retained against the ... When using dry-contact electrodes, the interface between the skin and the electrodes are mainly defined by the electrochemical ... typically by placing electrodes on the scalp. In ear-EEG, the electrodes are exclusively placed in or around the outer ear, ...
Standard electrode potentials (reduction potentials)[edit]. Each half-reaction has a standard electrode potential (E0. cell), ... The battery is made out of a zinc electrode in a ZnSO4 solution connected with a wire and a porous disk to a copper electrode ... and the anode is a standard hydrogen electrode where hydrogen is oxidized: ​1⁄2 H2 → H+ + e−.. The electrode potential of each ... Electrode potential values from Petrucci, R. H.; Harwood, W. S.; Herring, F. G. (2002). General Chemistry (8th ed.). Prentice- ...
VEP Electrode Placement[edit]. Electrode placement is extremely important to elicit a good VEP response free of artifact. In a ... one electrode is placed 2.5 cm above the inion and a reference electrode is placed at Fz. For a more detailed response, two ... Brainstem auditory evoked potentials are small AEPs that are recorded in response to an auditory stimulus from electrodes ... additional electrodes can be placed 2.5 cm to the right and left of Oz. ...
Electrodes[edit]. Electrodes in cells are mostly coke which has been purified at high temperatures. Pitch resin or tar is used ... Oxidation of the carbon anode increases the electrical efficiency at a cost of consuming the carbon electrodes and producing ...
Multiplate multiple electrode aggregometry[edit]. In the Multiplate analyzer, anticoagulated whole blood is mixed with saline ... The increase in impedance between the electrodes as platelets aggregate onto them, is measured and visualized as a curve.[ ... and a platelet agonist in a single use cuvette with two pairs of electrodes. ...
The positive electrode is nickel hydroxide, and the negative electrode is hydrogen ions, or protons. The hydrogen ions are ... On the positive electrode, nickel oxyhydroxide, NiO(OH), is formed: Ni(OH)2 + OH− ⇌ NiO(OH) + H2O + e−. The metal M in the ... The negative electrode reaction occurring in a NiMH cell is H2O + M + e− ⇌ OH− + MH. The charge reaction is read left-to-right ... By using an improved electrode separator and improved positive electrode, manufacturers claim the cells retain 70-85% of their ...
Electrodes and leads[edit]. Proper placement of the limb electrodes. The limb electrodes can be far down on the limbs or close ... However, "leads" can also be formed between a physical electrode and a virtual electrode, known as the Wilson's central ... Electrodes are the actual conductive pads attached to the body surface. Any pair of electrodes can measure the electrical ... Lead II is the voltage between the (positive) left leg (LL) electrode and the right arm (RA) electrode: ...
Zhang, W.; Ristein, J.; Ley, L. (2008). "Hydrogen-terminated diamond electrodes. II. Redox activity". Physical Review E. 78 (4 ...
The fiber also finds use in filtration of high-temperature gases, as an electrode with high surface area and impeccable ... to make carbon-fiber disk microelectrode or the fiber is cut to a length of 75-150 μm to make carbon-fiber cylinder electrode. ... "Fabrication of Amperometric Electrodes". Journal of Visualized Experiments (27). doi:10.3791/1040. PMC 2762914 ...
Ionspecific electrodes, ionspecific membrands Ionic conductivity Radiometry Nuclear radiation Absorption spectra Spectroscopy ...
This third electrode is used to give a rewarding electrical stimulus to the brain when the rat makes the correct move to the ... The electrodes do not move the animal directly, as if controlling a robot; rather, they signal a direction or action desired by ... Graham-Rowe, D. (2002). ""Robo-rat" controlled by brain electrodes". New Scientist. Retrieved 10 December 2013.. ... Some applications require electrodes to be implanted in the animal's nervous system connected to a receiver which is usually ...
"Except near the electrodes, where there are sheaths containing very few electrons, the ionized gas contains ions and electrons ... to one powered electrode, with a grounded electrode held at a small separation distance on the order of 1 cm. Such discharges ... Inductively coupled plasma (ICP): similar to a CCP and with similar applications but the electrode consists of a coil wrapped ... Corona discharge: this is a non-thermal discharge generated by the application of high voltage to sharp electrode tips. It is ...
palladium hydride: electrodes in cold fusion experiments. *lithium aluminium hydride: a powerful reducing agent used in organic ... The second mechanism is responsible for the observed temporary volume expansion of certain electrodes used in electrolytic ...
The electrodes are lowered onto the scrap, an arc is struck and the electrodes are then set to bore into the layer of shred at ... The electrodes solidify under vacuum. For VIM-VAR steels, the surface of the cooled electrodes must be ground to remove surface ... The advantage of DC is lower electrode consumption per ton of steel produced, since only one electrode is used, as well as less ... Continuous-process furnaces may also use paste-type, Søderberg electrodes to prevent interruptions from electrode changes. Such ...
An elastomeric film is coated on both sides with electrodes. The electrodes are connected to a circuit. By applying a voltage U ... arising from the Coulomb forces acts between the electrodes. The electrodes squeeze the elastomer film. The equivalent ... Materials used in research include graphite powder, silicone oil / graphite mixtures, gold electrodes. The electrode should be ... Replacing the electrodes with soft hydrogels allows ionic transport to replace electron transport. Aqueous ionic hydrogels can ...
Platinized platinum electrodes. Chemical Reviews. 1971, 71 (2): 177. doi:10.1021/cr60270a002.. ...
One half-cell includes electrolyte and the negative electrode, the electrode to which anions (negatively charged ions) migrate ... The net emf of the cell is the difference between the emfs of its half-cells.[16] Thus, if the electrodes have emfs E. 1. {\ ... The more electrode material contained in the cell the greater its capacity. A small cell has less capacity than a larger cell ... As a novelty or science demonstration, it is possible to insert two electrodes made of different metals into a lemon,[72] ...
The standard electrode potential for the equilibrium [M(H2O)6]2+ + [M(H2O)6]3+ ⇌ [M(H2O)6]3+ + [M(H2O)6]2+. Standard redox ...
The resistance between the electrodes also falls; the electronic ballast control gear registers this and automatically switches ... Electrical resistance is reduced within the channel, and current flows between the electrodes. ... creating a conducting channel between the tungsten electrodes. ...
A crucial factor for ISFET electrodes, as for conventional glass electrodes, remains thus the reference electrode. When ... An ISFET electrode sensitive to H+ concentration can be used as a conventional glass electrode to measure the pH of a solution ... However, it also requires a reference electrode to operate. If the reference electrode used in contact with the solution is of ... A too large volume constrained by a classical reference electrode also precludes the miniaturization of the ISFET electrode, a ...
Positive electrode: PF− 6 + n C ⇄ C n(PF 6) + e− Negative electrode: Li+ + n C + e− ⇄ LiC n Patent A US 3844837 A ; basic ... The electrodes are made from cotton, to better control the crystal size. A separate research project used the same salt and a ... Both electrodes are based on graphitic carbon. Graphite with the right grain size is obtained by pyrolyzing cotton. ... Capacity is determined by the storage capacity and amount of ion release of the electrodes and the amount of anions and cations ...
The electrodes are implanted as described above. The patient uses a hand-held magnet to turn on and turn off a pulse generator ... A low-frequency current is passed through the electrode to activate the tremor and to confirm proper placement. Once the site ... A small hole is drilled through the skull and a temperature-controlled electrode is inserted into the thalamus. ... Deep brain stimulation (DBS) uses implantable electrodes to send high-frequency electrical signals to the thalamus. ...
Electrodes are placed over bones to minimize artifacts from muscular activity. The number and position of electrodes varies by ... These electrodes are connected to a small piece of equipment that is attached to the patient's belt or hung around the neck, ... The quality itself mainly depends on the attachment of the electrodes to the patient body. If these are not properly attached, ... Besides the attachment and quality of electrodes, there are other factors affecting the signal quality, such as muscle tremors ...
Here, we report three types of nanostuctured materials as the counter electrode of dye-sensitized solar cells, including ... Pt prepared by hydrolysis was used as the counter electrode of dye-sensitized solar cells. But the hydrolysis requires a high- ... Traditionally, Pt prepared by hydrolysis was used as the counter electrode of dye-sensitized solar cells. But the hydrolysis ... Here, we report three types of nanostuctured materials as the counter electrode of dye-sensitized solar cells, including ...
The working electrode is often used in conjunction with an auxiliary electrode, and a reference electrode in a three electrode ... The working electrode is the electrode in an electrochemical system on which the reaction of interest is occurring.[1][2][3] ... Depending on whether the reaction on the electrode is a reduction or an oxidation, the working electrode is called cathodic or ... and mercury drop and film electrodes. Chemically modified electrodes are employed for the analysis of both organic and ...
To see the interfering effect of Na+ to a pH-electrode: E. =. E. 0. +. R. T. F. ln. ⁡. (. a. H. +. +. k. H. +. ,. Na. +. a. Na ... The pH electrode is an example of a glass electrode that is sensitive to hydrogen ions. Glass electrodes play an important part ... internal electrode, usually silver chloride electrode or calomel electrode. *internal solution, usually a pH=7 buffered ... The most common glass electrode is the pH-electrode. Only a few chalcogenide glass electrodes are sensitive to double-charged ...
Electrodes for Your Face Bring Your Emotions to Augmented and Virtual Reality. Tracking facial expressions can make VR and AR ... Advanced Electrodes for Better Li-Ion Batteries. Nanotube anodes could lead to higher-energy, faster-charging batteries for ... Eric Leuthardt believes that in the near future we will allow doctors to insert electrodes into our brains so we can ... Controlling Prosthetic Limbs with Electrode Arrays. A new nerve-cell-support design could give amputees better control over ...
The polymer film is readily deposited on the electrode surface and can be rendered stable by ionic or addition cross-linking. ... Electron transport between the electrode (12) and the mediator film (24) is favorable and photocorrosion and recombination ... 4. An electrode according to claim 2 in which the electrode further contains an effective amount of a catalyst capable of ... 1, a typical photoelectrochemical cell 10 comprises a p-type semiconductor electrode 12, and a counter-electrode 14 disposed in ...
A sheet-like electrode of this type may be used as a substitute for the commonly-used graphite electrodes in cell structures of ... The electrode sheets at either end of the tank are connected to bus bars and function as terminal electrodes. The remaining ... As the electrode wears away and hence the gap between the electrodes increases, there is an increase in the electrical ... Additionally, graphite electrodes are inherently less efficient electrically than metal electrodes. In view of the above- ...
However, the electrodes have to be coated with platinum to catalyse the fuel cells reactions, and a way of doing that using ... Read the full platinum nanotube electrode patent application.. Justin Mullins, New Scientist consultant. ...
Electrodes translate brain waves into words. The Utah study reported in the Journal of Neuroengineering shows promise for ... But such electrodes "are so far away from the electrical activity that it gets blurred out," Greger said. ... Greger believes the accuracy can be improved by using more electrodes, and the team is now working with grids of 121 sensors. ... But researchers have been reluctant to implant electrodes in the speech centers for fear of causing irreversible damage. ...
One case of OrthoTrode TENS electrodes contains ten packs of four electrodes each; a total of forty (40) electrodes per case. ... How important are TENS Electrodes?. OrthoCos is proud of its OrthoTrode line of reusable TENS Electrodes. TENS stands for ... The electrodes, which are applied to the skin, deliver intermittent simulation to surface nerves to block the transmission of ... Some patients actually need a number of TENS electrodes pads when using multi-channel TENS units. While OrthoCo ships ...
... pair of transparent sustain and discharge electrodes and an address electrode. An alternating current is applied continuously ... to the sustain electrode, the voltage of this current carefully chosen to be just below the threshold of a plasma discharge. ... Other articles where Discharge electrode is discussed: television: Plasma display panels: … ... pair of transparent sustain and discharge electrodes and an address electrode. An alternating current is applied continuously ...
It can be divided into two categories on the basis of the nature of the indicator electrode.… ... The potential of the indicator electrode varies, depending on the concentration of the analyte, while the potential of the ... reference electrode is constant. Potentiometry is probably the most frequently used electroanalytical method. ... potential is applied to the indicator electrode relative to the reference electrode. The analyte electrochemically reacts at ...
Electrically stimulating specific parts of the brain using an implanted electrode can help severely depressed patients, ... An x-ray shows the position of the electrode leads in the brain of one patient.. "This is a very promising therapy for severe ... Brain Electrodes Help Treat Depression. Studies suggest that deep brain stimulation could effectively treat depression. ... Stimulating brains: Electric currents delivered via electrodes surgically implanted into the brain alleviate depression in some ...
Keating, M.Y.; Rechnitz, G.A. (1983). Cortisol Electrode. Analyst (London) 108: 766-768.CrossRefGoogle Scholar ... Solsky, R.L.; Rechnitz, G.A. (1981). Preparation and Properties of an Antibody-Selective Membrane Electrode. Anal. Chim. Acta ... This class of membrane electrodes respond to specific antibodies through modulation of a background potential fixed by a marker ... Boitieux, J.-L.; Desmet, G.; Thomas, D. (1979). An "Antibody Electrode," Preliminary Report on a New Approach in Enzyme ...
Pushing electrodes deep into the brain allows precision targeting but requires risky surgery. Placing electrodes on the surface ... So while surgery is needed, it is a safer procedure: a hole is drilled in the skull and a tape with several electrodes on ... With this technique, rather than placing the electrodes inside the brain, they are put on its surface. ...
The electrode terminal (front) of a pacemaker is located at the front of the electrode tip in the inferior aspect of the heart ...
... diffuse layer distance drop effect electrochemical reaction electrochemistry electrode kinetics electrode reaction electrode ... reactant reaction coordinate reaction layer reactions in solution reduction reversible ring electrode rotating disc electrode ... books.google.comhttps://books.google.com/books/about/Electrode_kinetics.html?id=EY00AAAAMAAJ&utm_source=gb-gplus-shareElectrode ... 0 Reviewshttps://books.google.com/books/about/Electrode_kinetics.html?id=EY00AAAAMAAJ ...
... are thin and flexible for easier placement and to conform to the curvature of the cortical ... Integra Epilepsy Grid Electrodes. Features. Cortical Grid Electrode with Cylindrical Connector. Standard spacing between ... Integra Epilepsy Flex Connector Grid Electrodes. 11. Integra Epilepsy Gates/Dunn Electrodes. ... Integra Epilepsy grid electrodes are thin and flexible for easier placement and to conform to the curvature of the cortical ...
Ion-selective electrodes (ISEs) have a wide range of applications in clinical, environmental, food and pharmaceutical analysis ... Classification of ISEs Crystalline ISE Glass ISE ISE Ion-Selective Electrode Ionophore-Based ISE Membrane Potential Theory ... Ion-selective electrodes (ISEs) have a wide range of applications in clinical, environmental, food and pharmaceutical analysis ... 1., Ion-Selective Electrode LaboratorySt. Petersburg State UniversitySt. PetersburgRussia ...
I seem to have had an allergic reaction to something in the electrodes that were attached to my skin, but Im not 100% sure. ... This morning when I removed them, the places where the electrodes - or rather the gel on them - touched my skin were red. The ... When the technician first attached the electrodes, they stung and burned, with a little itching. This continued but decreased ... Could it be that you are just allergic to the mild adhesive that is in the electrodes? ...
... 09.05.2014. Freiburg researchers develop new method for lowering high blood pressure without ... Now that the scientists have determined that a cuff with electrodes is feasible in principle, they have begun to develop a ... Josef Zentner from the Medical Center - University of Freiburg to develop a new cuff equipped with electrodes that can lower ... The device starts by determining which electrode is closest to the nerve fibers that transmit the blood pressure signal. Then ...
Interhemispheric Grid Electrode with 16 Contact Leads; Cortical Grid Electrode with 16 Contact Leads; Pediatric Grid Electrode ... Dual-sided, Interhemispheric Grid Electrode with 16 Contact Leads; Cortical Grid Electrode with 16 Contact Leads; Pediatric ... Grid Electrode with Flex Connector, 0.5 cm spacing. Info. Integra LifeSciences Corporation. Customer Service: (800) 654-2873. ...
Fatigue-free and biocompatible electrodes. Chuan Fei Guo, Qihan Liu, Guohui Wang, Yecheng Wang, Zhengzheng Shi, Zhigang Suo, ... Fatigue-free and biocompatible electrodes. Chuan Fei Guo, Qihan Liu, Guohui Wang, Yecheng Wang, Zhengzheng Shi, Zhigang Suo, ... Fatigue-free, superstretchable, transparent, and biocompatible metal electrodes. Chuan Fei Guo, Qihan Liu, Guohui Wang, Yecheng ... A metal mesh that conducts electricity, is biocompatible, and is completely free of fatigue will be an ideal electrode not only ...
Fuel cell electrodes and method of making the same. US3236693 *. 11 Oct 1963. 22 Feb 1966. Socony Mobil Oil Co Inc. Electrode ... Method for making electrodes. WO2007072096A1 *. 22 Dec 2006. 28 Jun 2007. Thalesnano Zrt.. Electrode for electrochemical cell ... Electrochemical electrode. US3423247 *. 19 May 1964. 21 Jan 1969. Union Carbide Corp. Porous conductive electrode having at ... Air was passed on one side of the oxidizing electrode and kerosene vapors were passed on one `side of the fuel electrode. The - ...
... Gelines Moreno-Fernandez,1 Joaquin Ibañez,2 Jose M. Rojo,1 and ... Lillo-Ródenas, J. Ibañez, and J. M. Rojo, "New carbon monoliths for supercapacitor electrodes. Looking at the double layer," ... K. Leitner, A. Lerf, M. Winter et al., "Nomex-derived activated carbon fibers as electrode materials in carbon based ... "Various treated conditions to prepare porous activated carbon fiber for application in supercapacitor electrodes," Energy and ...
The United States International Trade Commission is an independent, nonpartisan, quasi-judicial federal agency that fulfills a range of trade-related mandates. We provide high-quality, leading-edge analysis of international trade issues to the President and the Congress. The Commission is a highly regarded forum for the adjudication of intellectual property and trade disputes.
  • Greger believes the accuracy can be improved by using more electrodes, and the team is now working with grids of 121 sensors. (latimes.com)
  • Innovative Sensors, Inc. has announced two new SPECTRA series electrodes. (chemicalonline.com)
  • One particular aim of modern research is the development of an eliicient electrochemically stable electrode Awhich is not detrimentally attacked, even at high temperatures, by the electrolyte of the cell. (google.com.au)
  • The electrode in one preferred embodiment comprises a porous cermet consisting of two layers in intimate contact with each other, the layer fronting the electrolyte consisting of zinc oxide bonded with metallic silver and the layer fronting the fuel consisting of alumina or aluminum silicate impregnated with an activating metal. (google.com.au)
  • 4. The process of claim 1, wherein an electrolyte is placed in the borehole and flows into the effective electrode. (google.de)
  • 50ml bottle of 3M KCI is required electrolyte refilling and the recommed storaging solution for all our pH electrodes. (sartorius.com)
  • These thin and flexible solid electrolyte membranes will be laminated to lithium metal foils, which can then be used to replace the graphite electrode and separators in commercial Li-ion batteries. (energy.gov)
  • An electrode is an electrical conductor used to make contact with a nonmetallic part of a circuit (e.g. a semiconductor, an electrolyte, a vacuum or air). (wikipedia.org)
  • Working electrode Reference electrode Gas diffusion electrode Battery Redox Reaction Cathodic protection Galvanic cell Anion vs. Cation Electron versus hole Electrolyte Electron microscope Noryl Tafel equation Hot cathode Cold cathode Electrolysis Reversible charge injection limit Weinberg, Steven (2003). (wikipedia.org)
  • For electric arc welding with stick electrodes, an electric arc is generated between the stick electrode and the base material. (voestalpine.com)
  • Each type of steel needs a different stick electrode. (voestalpine.com)
  • Because variables such as storage techniques, electrode diameter and flux composition all contribute to stick electrode selection and performance, arming yourself with some basic knowledge can help you minimize confusion and better ensure stick welding success. (millerwelds.com)
  • Codes take the form of numbers and letters printed on the side of each stick electrode, and each represents specific electrode properties. (millerwelds.com)
  • Ten times more power than lithium ion -- but still ten years off: A fluffy carbon electrode has brought scientists at Cambridge University a step closer to producing a workable lithium-air battery, but many technical challenges remain. (pcworld.com)
  • The atmospheric problem is still unsolved, but in a paper published in the journal Science on Friday, researchers at Cambridge University describe how they have solved some of the stability and efficiency problems by adding lithium iodide and using a fluffy carbon electrode made of sheets of graphene. (pcworld.com)
  • In the lithium-air battery developed by Tao Liu, Clare P. Grey and colleagues at Cambridge, the carbon electrode is made of a porous form of graphene. (pcworld.com)
  • A simple cell comprises a housing, a fuel electrode, an oxidizing electrode, and an external means for drawing off electrical current. (google.com.au)
  • SUMMARY OF THE INVENTION Briefly described, the apparatus of this invention comprises one or more flexible electrodes connected to leads which are adapted to be connected to a source of electrical signal. (google.co.uk)
  • The gate electrode comprises a metal film formed directly adjacent to the gate dielectric layer. (google.es)
  • In a first step toward helping severely paralyzed people communicate more easily, Utah researchers have shown that it is possible to translate recorded brain waves into words, using a grid of electrodes placed directly on the brain. (latimes.com)
  • Integra Epilepsy grid electrodes are thin and flexible for easier placement and to conform to the curvature of the cortical surface. (bio-medicine.org)
  • An electronic circuit for sensing an output of a sensor having at least one electrode pair and circuitry for obtaining and processing the sensor output. (google.ca)
  • These electrodes are intended for use with the MyoWare Muscle Sensor from Advancer Technologies. (pololu.com)
  • MyoWare Muscle Sensor with electrodes attached, top view. (pololu.com)
  • latex-free) provides enough electrodes for two applications when used with the MyoWare Muscle Sensor . (pololu.com)
  • The snap connector built into each electrode allows for easy installation and removal: they snap directly into the MyoWare Muscle Sensor. (pololu.com)
  • For instructions on how to use the electrodes with the MyoWare Muscle Sensor, please refer to the MyoWare datasheet available on the muscle sensor product page . (pololu.com)
  • Ion-selective electrodes (ISEs) have a wide range of applications in clinical, environmental, food and pharmaceutical analysis as well as further uses in chemistry and life sciences. (springer.com)
  • Coverage includes the basics of measuring with ISEs, essential membrane potential theory and a comprehensive overview of the various classes of ion-selective electrodes. (springer.com)
  • A pack of three non-sterile spring clip (spring metal plated with nickel and gold) electrodes, each having a 1 m lead wire and terminating to a 2 mm pin connector. (adinstruments.com)
  • Depending on whether the reaction on the electrode is a reduction or an oxidation, the working electrode is called cathodic or anodic , respectively. (wikipedia.org)
  • The remaining sheets function as bipolar electrodes each having one face cathodic and one face anodic in successive unit cells. (google.com)
  • 1. An endocardial electrode assembly, said assembly comprising three or more elongated insulated wire spring legs joined together at least in a region spaced from the distal end of said assembly, said assembly constructed to be inserted into the heart while surrounded by a distal portion of a catheter, and to be exposed to active position by proximal movement of the catheter to a partially withdrawn position relative to said assembly. (google.co.uk)
  • A catheter having expandable electrodes for applying energy to a vein for a minimally invasive treatment of venous insufficiency, and having expandable stent members for limiting vein shrinkage to a final desired vein diameter. (google.es)
  • Long-term electrode catheter pacing from coronary sinus. (bmj.com)
  • In the past the most frequently used material for the bipolar electrodes has been graphite. (google.com)
  • In view of the above-described disadvantages of graphite bipolar electrodes, attention has been directed to finding other materials more Suitable for bipolar electrodes. (google.com)
  • The positive and negative electrodes in Li-ion batteries are made of a metal oxide and of graphite, respectively. (pcworld.com)
  • The material is made of vanadium oxide (V 2 O 5 ) and lithium-borate (LiBO 2 ) precursors, and was coated with reduced graphite oxide (RGO) to enhance the electrode properties of the material. (nanowerk.com)
  • To produce an efficient electrode, the researcher coated the vanadate-borate powder with reduced graphite oxide (RGO). (nanowerk.com)
  • Get results three to five times more precise than those obtained with conventional electrodes with the Thermo Scientific™ Orion™ 8101BNWP ROSS™ Half-Cell Electrode. (fishersci.com)
  • The researcher therefore sees the metallized leaves as an alternative to conventional electrodes for solar cells. (idw-online.de)
  • More particularly, the invention relates to a method for creating a carbonaceous current-carrying deposit in a formation surrounding a borehole, and to the enlarged-radius electrode thus formed from the deposit. (google.de)
  • Many biosensors have been developed for the determination of analytes in the biological samples, namely, spectrometry, potentiometry with application of pH sensitive electrode or an ion selective electrode or an ion sensitive field effective transistor, conductometry, coulometry, amperometry, and inductometry [ 1 - 13 ]. (hindawi.com)
  • International researchers have collaborated on the creation of biocompatible electrodes that could be used to treat neurological disorders including epilepsy. (theengineer.co.uk)
  • An alternating current is applied continuously to the sustain electrode, the voltage of this current carefully chosen to be just below the threshold of a plasma discharge. (britannica.com)
  • An electrode array is a configuration of electrodes used for measuring either an electric current or voltage. (dbpedia.org)
  • Some electrode arrays can operate in a bidirectional fashion, in that they can also be used to provide a stimulating pattern of electric current or voltage. (dbpedia.org)
  • When the neurons in the brain transmit signals, a voltage is formed that the electrodes detect and transmit onwards through a tiny amplifier," said Tybrandt. (theengineer.co.uk)
  • The redox reaction in terms of measuring the loss or formation of substrate or product, the use of a small mediator species that shuttles between the biomolecule and the electrode, or direct electron transfer (ET) between the biomolecule redox site and the electrode. (hindawi.com)
  • The high stability of the electrode potential is usually reached by employing a redox system with constant (buffered or saturated) concentrations of each participant of the redox reaction. (wikipedia.org)
  • Glass electrodes have been utilized in a wide range of applications including pure research, control of industrial processes, analysis of foods and cosmetics, measurement of environmental indicators, and microelectrode measurements such as cell membrane electrical potential and soil acidity. (wikipedia.org)
  • As the electrode wears away and hence the gap between the electrodes increases, there is an increase in the electrical resistance of the cell, with consequent power losses. (google.com)
  • But such electrodes "are so far away from the electrical activity that it gets blurred out," Greger said. (latimes.com)
  • An improved electrode for implantation into a body including one or more electrical conductor leads adapted to be connected to a source of electrical signal, and one or more flexible electrodes attached to the leads, so that the electrodes may be bent around the portion of the body to which they are. (google.co.uk)
  • The structure of the electrodes which connect the electrical signals from an implantable device to a desired portion of the body, has been found to be highly important to those skilled in the art. (google.co.uk)
  • A borehole that is completed as a well and having appropriate electrical features so that it can function as an electrode in contact with the adjacent formation is known as an electrode well. (google.de)
  • The utility of the invention lies in the heating, by electrical means, of a subterranean formation, between two or more boreholes, as the step following the formation of the carbonaceous electrode. (google.de)
  • Broadly, when an electrical current is used in a subterranean formation to heat the formation, it is desirable to have an electrode of substantial size. (google.de)
  • A 5-μm-diameter needle-electrodes on 1 mm 1 mm block modules is developed by a research team in the Department of Electrical and Electronic Information Engineering and the Electronics-Inspired Interdisciplinary Research Institute (EIIRIS) at Toyohashi University of Technology. (medindia.net)
  • Microfabricated silicon needle-electrode devices were expected to be an innovation that would be able to record and analyze the electrical activities of the microscale neuronal circuits in the brain. (medindia.net)
  • The electrode may be embedded in the wall of the organ so that only neural and contractile cells located within this wall will be excited when electrical stimuli are applied. (freepatentsonline.com)
  • Thus, they have much in common with the electrodes in solar cells, batteries or LEDs that collect or distribute electrical current or signals,' explains Dr. Jonathan Plentz, who heads the 'Photonic Thin Film Systems' working group at Leibniz IPHT. (idw-online.de)
  • In a new development, scientists have developed a synthetic "biowire" to improve the electrical connections between two electrodes. (digitaljournal.com)
  • Electrodes can be used to detect electrical activity such as brain waves. (yourdictionary.com)
  • Terminal points in electrical components such as transistors, diodes, and batteries are electrodes. (yourdictionary.com)
  • Typically an end point or wire made of metal or some composite material, there are countless electrodes in electrical and electronics products. (yourdictionary.com)
  • Sequence-Specific Electrical Purification of Nucleic Acids with Nanoporous Gold Electrodes. (nih.gov)
  • A range of non-sterile spring clip (spring metal plated with nickel and gold) electrode packs that are suitable for use with compatible ADInstruments Bio Amps for measuring electrical activity from an isolated heart preparation, either in a Langendorff or Working Heart mode. (adinstruments.com)
  • An electrode is an electrical conductor used to make contact with a non-metallic part of a circuit. (ltu.se)
  • For electrical systems which use alternating current, the electrodes are the connections from the circuitry to the object to be acted upon by the electric current but are not designated anode or cathode because the direction of flow of the electrons changes periodically, usually many times per second. (wikipedia.org)
  • the legs comprising insulated conductors connected to respective sets of spaced electrodes carried by the legs, said spring legs having predetermined shape and position to spring relatively apart to cause the electrodes to engage with wall tissue within a cavity of the heart, in the manner that a three dimensional array of spaced electrode contact points can be simultaneously made with the wall of the beating heart. (google.co.uk)
  • The electrodes include a pair of parallel spaced apart helically wound conductors maintained in this configuration. (freepatentsonline.com)
  • New types of high-performance separators and electrodes built with solid-state ion conductors could simultaneously improve the energy density and safety of lithium ion batteries by removing the most flammable battery components, and also improving the driving range and durability of electric vehicles. (energy.gov)
  • Some researchers have been attempting to "read" speech centers in the brain using electrodes placed on the scalp. (latimes.com)
  • Placing electrodes on the surface of the scalp carries little-to-no health risk, but it cannot be focused on an area of less than 4 square centimetres. (newscientist.com)
  • When studying the brain by means of electrodes, these are either placed on the scalp (electroencephalography - EEG), under the surface of the scalp and skull directly on the brain's surface (electrocorticography), or into specific brain areas. (greenfacts.org)
  • 3. What are the differences between 6010, 6011, 6012 and 6013 electrodes and when should they be used? (millerwelds.com)
  • 6011 electrodes can also be used for all-position welding using an alternating current (AC) welding power source. (millerwelds.com)
  • Like 6010 electrodes, 6011 electrodes produce a deep, penetrating arc that cuts through corroded or unclean metals. (millerwelds.com)
  • Many welders choose 6011 electrodes for maintenance and repair work when a DC power source is unavailable. (millerwelds.com)
  • 6010 electrodes deliver deep penetration and have the ability to "dig" through rust, oil, paint or dirt, making them popular among pipe welders. (millerwelds.com)
  • 6010 electrodes can only be used with direct current (DC) power sources. (millerwelds.com)
  • However, 6010 electrodes feature an extremely tight arc, which can make them difficult for novice welders to use. (millerwelds.com)