Concentric ring electrodes are noninvasive and wearable sensors for electrophysiological measurement capable of estimating the surface Laplacian (second spatial derivative of surface potential) at each electrode. Significant progress has been made toward optimization of inter-ring distances (distances between the recording surfaces of the electrode), maximizing the accuracy of the surface Laplacian estimate based on the negligible dimensions model of the electrode. However, novel finite dimensions model offers comprehensive optimization including all of the electrode parameters simultaneously by including the radius of the central disc and the widths of the concentric rings into the model.
View Article and Find Full Text PDFThe optimization performed in this study is based on the finite dimensions model of the concentric ring electrode as opposed to the negligible dimensions model used in the past. This makes the optimization problem comprehensive, as all of the electrode parameters including, for the first time, the radius of the central disc and individual widths of concentric rings, are optimized simultaneously. The optimization criterion used is maximizing the accuracy of the surface Laplacian estimation, as the ability to estimate the Laplacian at each electrode constitutes primary biomedical significance of concentric ring electrodes.
View Article and Find Full Text PDFRats were exposed to nickel oxide nano-aerosol at a concentration of 2.4 ± 0.4 µg/m in a "nose only" inhalation setup for 4 h at a time, 5 times a week, during an overall period of 2 weeks to 6 months.
View Article and Find Full Text PDFRats were exposed 3 times a week during 6 weeks to repeated intraperitoneal injections of lead acetate solution in water (Pb) and/or benzo(а)pyrene solution in petrolatum oil (B(а)P) in various dose ratios. Towards the end of the period, the animals developed a moderate subchronic intoxication having some features characteristic of lead effects. The type of combined toxicity estimated with the help of isoboles constructed by the Response Surface Methodology was found to be varied depending on a particular effect, its level, and dose ratio.
View Article and Find Full Text PDFOver the past few years, the Ekaterinburg (Russia) interdisciplinary nanotoxicological research team has carried out a series of investigations using different and experimental models in order to elucidate the cytotoxicity and organ-systemic and organism-level toxicity of lead-containing nanoparticles (NP) acting separately or in combinations with some other metallic NPs. The authors claim that their many-sided experience in this field is unique and that some of their important results have been obtained for the first time. This paper is an overview of the team's previous publications in different journals.
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