Spiral waves are observed in the chemical, physical and biological systems, and the emergence of spiral waves in cardiac tissue is linked to some diseases such as heart ventricular fibrillation and epilepsy; thus it has importance in theoretical studies and potential medical applications. Noise is inevitable in neuronal systems and can change the electrical activities of neuron in different way...

We report the complex dynamics of spiral waves observed in the ferroin-catalyzed BZ reaction. The reaction is run in an open unstirred reactor (CFUR) with the catalyst immobilized on a polysulfone membrane. The catalyst-loaded membrane is placed between two well stirred compartments which are fed with solutions of sulfuric acid/malonic acid/bromide and sulfuric acid/bromate, respectively. An el...

A regular network of neurons is constructed by using the Morris-Lecar (ML) neuron with the ion channels being considered, and the potential mechnism of the formation of a spiral wave is investigated in detail. Several spiral waves are initiated by blocking the target wave with artificial defects and/or partial blocking (poisoning) in ion channels. Furthermore, possible conditions for spiral wav...

Human gastric epithelial immortalized GES-1 cells were infected with spiral and coccoid Helicobacter pylori. Scanning electron microscopy was used to determine the ability of the two forms of H. pylori to adhere to GES-1 cells. GES-1 cell apoptosis induced by coccoid and spiral H. pylori was analysed using flow cytometry. A cDNA microarray for 22,000 human genes was used to identify the gene-ex...

The determination of the mechanisms of spiral breakup in excitable media is still an open problem for researchers. In the context of cardiac electrophysiological activities, spiral breakup exhibits complex spatiotemporal pattern known as ventricular fibrillation. The latter is the major cause of sudden cardiac deaths all over the world. In this paper, we numerically study the instability of per...

This is the first scanning electron microscopic demonstration of the three-dimensional architecture and detailed surface structures of the entire osseous labyrinth of the cochlea. Mouse cochleae were observed after dissolving the soft tissues with KOH and NaOCl solutions. The precise shapes, surface structures, and orientations of the primary osseous spiral lamina and secondary osseous spiral l...

Selection of spiral capillary tube for refrigeration appliances and the effect of changes in the parameters such as capillary tube dimensions i.e. capillary tube diameter, coil pitch, capillary tube length and inlet conditions of refrigerant to the capillary tube i.e. degree of subcooling, inlet pressure on the mass flow rate of the refrigerant, also investigation about the coiling effect of sp...

In this paper, the three-dimensional geometry of the human cochlea is modeled by the helico-spiral seashell model. The 3-D helico-spiral model, the generalized representation of the Archimedian spiral model, provides a framework for measuring cochlear features based on consistent estimation of model parameters. Nonlinear least square minimization based algorithms are developed for the identific...

The introduction of spiral technology to computed tomography (CT) scanners in the late 1980s has revolutionised the field ofCT. Spiral CT offers definite practical benefits over conventional scanners and has expanded the role of CT through the development of new scanning techniques. CT scanning now rivals magnetic resonance imaging in many areas of investigation, and for some situations is the ...

Shock induced star formation in a stellar density wave scenario produces an azimuthal gradient of ages across the spiral arms which has opposite signs on either side of the corotation resonance (CR). We present a method based on the Fourier analysis of azimuthal profiles, to locate the CR and determine the arm character (trailing or leading) in spiral galaxies. Basically, we compare the behavio...