Search results for "Electrode"
showing 10 items of 950 documents
Adsorption enrichment of some azo dye complexes on a carbon paste electrode and its application to the determination of small concentrations of cobal…
1974
The azo dyes eriochrome black T, eriochrome blueblack R and eriochrome blueblack B and their complexes with cobalt, manganese and magnesium show adsorption enrichment on carbon paste electrodes, dependent on the composition of the electrode filling. This effect may be used for the determination of cobalt and manganese by a.c. voltammetry in the 10−7 to 10−6 M range. Standard deviation has been found to be ± 3.2 and ± 3.5%, respectively.
Electropolymerization of non-substituted Mg(II) porphine: Effects of proton acceptor addition
2015
Abstract Electropolymerization of unsubstituted magnesium porphine in acetonitrile solutions possessing various proton-accepting properties has been studied. The overall rate of the polymer-product accumulation on the electrode surface has been established to be limited by the deprotonation step of intermediate species. This conclusion is based on the observed influence of proton-accepting additives, water or 2,6-dimethylpyridine (lutidine), on the Mg-porphine electrooxidation process. Lutidine addition into the polymerization bath enables one to enhance strongly the rate of the film growth and the efficiency of this process increases more than by a factor of two, redox, electric conductivi…
Mild systemic inflammation and moderate hypoxia transiently alter neuronal excitability in mouse somatosensory cortex
2016
During the perinatal period, the brain is highly vulnerable to hypoxia and inflammation, which often cause white matter injury and long-term neuronal dysfunction such as motor and cognitive deficits or epileptic seizures. We studied the effects of moderate hypoxia (HYPO), mild systemic inflammation (INFL), or the combination of both (HYPO + INFL) in mouse somatosensory cortex induced during the first postnatal week on network activity and compared it to activity in SHAM control animals. By performing in vitro electrophysiological recordings with multi-electrode arrays from slices prepared directly after injury (P8–10), one week after injury (P13–16), or in young adults (P28–30), we investig…
Anodal tDCS of the swallowing motor cortex for treatment of dysphagia in multiple sclerosis: a pilot open-label study
2017
Swallowing difficulties are a common symptom of multiple sclerosis (MS). The early detection and treatment of dysphagia is critical to prevent complications, including poor nutrition, dehydration, and lung infections. Recently, transcranial direct current stimulation (tDCS) has been proven to be effective in ameliorating swallowing problems in stroke patients. In this pilot study, we aimed to assess safety and efficacy of transcranial direct current stimulation (tDCS) in the treatment of dysphagia in MS patients. We screened 30 patients by using the 10-item DYsphagia in MUltiple Sclerosis (DYMUS) questionnaire, and patients at risk for dysphagia underwent a clinical and fiberoptic endoscopi…
Optogenetic Modulation of a Minor Fraction of Parvalbumin-Positive Interneurons Specifically Affects Spatiotemporal Dynamics of Spontaneous and Senso…
2017
Abstract Parvalbumin (PV) positive interneurons exert strong effects on the neocortical excitatory network, but it remains unclear how they impact the spatiotemporal dynamics of sensory processing in the somatosensory cortex. Here, we characterized the effects of optogenetic inhibition and activation of PV interneurons on spontaneous and sensory-evoked activity in mouse barrel cortex in vivo. Inhibiting PV interneurons led to a broad-spectrum power increase both in spontaneous and sensory-evoked activity. Whisker-evoked responses were significantly increased within 20 ms after stimulus onset during inhibition of PV interneurons, demonstrating high temporal precision of PV-shaped inhibition.…
Muscle Activity and Inactivity Periods during Normal Daily Life
2013
Recent findings suggest that not only the lack of physical activity, but also prolonged times of sedentary behaviour where major locomotor muscles are inactive, significantly increase the risk of chronic diseases. The purpose of this study was to provide details of quadriceps and hamstring muscle inactivity and activity during normal daily life of ordinary people. Eighty-four volunteers (44 females, 40 males, 44.1±17.3 years, 172.3±6.1 cm, 70.1±10.2 kg) were measured during normal daily life using shorts measuring muscle electromyographic (EMG) activity (recording time 11.3±2.0 hours). EMG was normalized to isometric MVC (EMGMVC) during knee flexion and extension, and inactivity threshold o…
European Clinical Experience with a Dual Chamber Single Pass Sensing and Pacing Defibrillation Lead
2002
Dual chamber ICDs are increasingly implanted nowadays, mainly to improve discrimination between supraventricular and ventricular arrhythmias but also to maintain AV synchrony in patients with bradycardia. The aim of this study was to investigate a new single pass right ventricular defibrillation lead capable of true bipolar sensing and pacing in the right atrium and integrated bipolar sensing and pacing in the right ventricle. The performance of the lead was evaluated in 57 patients (age 61 +/- 12 years; New York Heart Association 1.9 +/- 0.6, left ventricular ejection fraction 0.38 +/- 0.15) at implant, at prehospital discharge, and during a 1-year follow-up. Sensing and pacing behavior of…
Gold vs. platinum-iridium tip catheter for cavotricuspid isthmus ablation: the AURUM 8 study
2010
Aims Gold electrodes have the theoretical advantage of creating bigger lesions than platinum–iridium (Pt–Ir) electrodes. We performed a prospective randomized study to compare the clinical efficacy of standard 8 mm Pt–Ir tip catheter (control) and 8 mm gold-tip catheters in the ablation of the cavotricuspid isthmus (CTI)-dependent atrial flutter. Methods and results A total of 463 patients undergoing CTI ablation in 19 clinical centres were randomized to receive the treatment by gold-tip or control catheter. The primary endpoint was cumulative radiofrequency (RF) application duration until achieving bidirectional CTI block. It did not differ significantly for the two catheters. The gold-tip…
Hippocampo-cerebellar theta band phase synchrony in rabbits.
2009
Hippocampal functioning, in the form of theta band oscillation, has been shown to modulate and predict cerebellar learning of which rabbit eyeblink conditioning is perhaps the most well-known example. The contribution of hippocampal neural activity to cerebellar learning is only possible if there is a functional connection between the two structures. Here, in the context of trace eyeblink conditioning, we show (1) that, in addition to the hippocampus, prominent theta oscillation also occurs in the cerebellum, and (2) that cerebellar theta oscillation is synchronized with that in the hippocampus. Further, the degree of phase synchrony (PS) increased both as a response to the conditioning sti…
Measurement of substrate-induced oxygen uptake during microsomal drug oxidation using a gold micro-electrode.
1975
1. A resin-coated gold micro-electrode has been used for polarographic determination of oxygen concentration in liver microsomal suspensions from phenobarbital-pretreated rats. 2. The rate of oxygen uptake on addition of an NADPH-regenerating system and the rate after addition of various substrates of the mixed function oxidase system were measured. The rate of oxygen uptake was faster in the presence of substrate than in the presence of NADPH alone. 3. Kinetic constants (Km and V max) for biphenyl, hexobarbital, ethylmorphine, naphthalene and SKF 525-A measured by this technique compare favourably with those obtained either by measurements of NADPH oxidation, or chemical measurements of su…