It has been proposed that ventricular fibrillation (VF) is driven by sustained reentry. However, mapping studies have not detected such "mother rotors" in large mammalian hearts. We mapped VF from three 21x12 unipolar electrode arrays in 6 pigs. Two of the arrays were adjacent to each other on the left-ventricular epicardium. Electrode spacing was 2 mm. The third array consisted of 21 needles (...

As sensors, wireless communication devices, personal health monitoring systems, and autonomous microelectromechanical systems (MEMS) become distributed and smaller, there is an increasing demand for miniaturized integrated power sources. Although thin-film batteries are well-suited for on-chip integration, their energy and power per unit area are limited. Three-dimensional electrode designs hav...

In article number 2000223, Silvia Ronchi, Michele Fiscella, and co-workers show neurons plated on a high-density microelectrode array. The small electrode size the tight spacing between 26 400 electrodes enable functional extracellular electrophysiological characterization of across scales, from subcellular-resolution features, like axons dendrites, through individual neuronal cells to entire n...

We demonstrate a device geometry for single-molecule electronics experiments that combines both the ability to adjust the spacing between the electrodes mechanically and the ability to shift the energy levels in the molecule using a gate electrode. With the independent in-situ variations of molecular properties provided by these two experimental "knobs", we are able to achieve a much more detai...

In this paper, the effect of surface area of reaction layers in gas diffusion electrodes on oxygen reduction reaction was investigated. For this purpose, various amounts (0.1, 0.2, 0.3, 0.4, 0.5, 1, 1.5 and zero %wt of total loading of reaction layer) of single walled carbon nanotube (SWCNT) were inserted in the reaction layer. The performance of gas diffusion electrodes for oxygen reduction re...

wet ag/agcl electrodes, although very popular in clinical diagnosis, are not appropriate for expanding applications of wearable biopotential recording systems which are used repetitively and for a long time. here, the development of a low‑cost and low‑noise active dry electrode is presented. the performance of the new electrodes was assessed for recording electrocardiogram (ecg) and electroence...

Electrical impedance tomography extends to the new and new areas of the medical diagnostics: lungs, breast, prostate, etc. The feedback from the doctors who use our breast EIT diagnostic system has induced us to develop the 3D electrical impedance imaging device for diagnostics of the cervix of the uterus gynecologic impedance tomograph (GIT). The device uses the same measuring approach as the ...

abstract background: heavy metals in industrial wastewater especially chromium (vi) are considered as the main environmental pollutants. methods: electrochemical cell made of plexiglass with a volume of 1.95 lit was used. iron and graphite electrodes, electricity conductor, each with dimensions of 0.1×3×10 cm (width×length×height) were designed and built. tests were carried out in various condi...

An experimental/computation investigation was carried out to develop a MEMS-based micro cooling device to provide direct cooling to high heat flux electronics and MEMS devices. This device uses the electrohydrodynamic principles to pump and form an ultra thin film over a heated surface that requires cooling. The important part is played by applying an electric field to a set of interdigitated i...

We have developed a hardware and software package for real-time discrimination of multiple-unit activities recorded simultaneously from multiple microelectrodes using a VME-Bus system. Compared with other systems cited in literature or commercially available, our system has the following advantages. (1) Each electrode is served by its own preprocessor (DSP32C); (2) On-line spike discrimination ...