Abstract Measurements of dielectrophoretic collection spectra Escherichia coli and Staphylococcus aureus suspensions are used for obtaining dielectric characteristics both types bacteria. The experiments interpreted using a numerical method that models the cells as compartmented spherical or rod‐like particles. We show usefulness this simple to extract significant information about electrical properties Gram‐negative ‐positive Bioelectromagnetics 28:393–401, 2007. © 2007 Wiley‐Liss, Inc.

Progress in microelectrode-based technologies has facilitated the development of sophisticated methods for manipulating and separating cells, bacteria, other bioparticles. For many these various applications, theoretical modeling electrical response compartmentalized particles to an external field is important. In this paper we address analysis interaction between cells immersed rf fields. We use integral formulation problem derived from a consideration charge densities induced at interfaces...

To determine why some pathways but not others produce sizable local field potentials (LFPs) and how far from the source can these be recorded, complementary experimental analyses realistic modeling of specific brain structures are required. In present study, we combined multiple in vivo linear recordings rats a tridimensional finite element model dentate gyrus, curved structure displaying abnormally large positive LFPs. We demonstrate that polarized dendritic arbour granule cells (GCs), with...

Nanostructure formation on Co(110) surfaces was studied by using irradiation with cluster ion beams oblique incidence and an energy of 250 eV/atom. In this work, the effect mass projectiles process analyzed. The launched clusters were formed different types charged atoms: He, Ne, Ar, Kr, Xe. Due to collision processes, surface patterns stand out more if projectile atoms is greater, regardless angle clusters. Two processes control morphological evolution during bombardment phase: sputtering...

This paper shows the importance of using a cell model with proper geometry, orientation and internal structure to study possible cellular effects from direct radiofrequency exposure. For this purpose, electric field intensity is calculated, finite element numerical technique, in single- multilayer spherical, cylindrical ellipsoidal mammalian models exposed linearly polarized electromagnetic plane waves frequencies 900 2450 MHz. An extensive analysis performed on influence that geometry...

We use the Maxwell stress tensor to calculate dielectrophoretic force and electrorotational torque acting on a realistic four-shelled model of yeast Saccharomyces cerevisiae in nonuniform rotating electric field generated by four coplanar square electrodes. The comparison these results with numerical calculations dipolar quadrupolar contributions obtained from an integral equation for polarization charge density shows effect quadrupole contribution proximity electrode plane. also show that...

We combine experimental electrorotation data and the numerical analysis of chamber cell to electrically characterize Saccharomyces cerevisiae yeast budding cycle obtain electrical parameters cell. To model we use spherical doublet-shaped geometries with a four layered structure: cytoplasm, membrane, inner outer walls. derive geometrical flnite element method calculate rotational velocity spectrum apply least-square flt calculated values data. show that spectra undergo signiflcant changes...

The salt permeability through three commercial cation-exchange membranes with different morphologies is investigated in aqueous NaCl solutions. Ion-exchange (IEMs) find application processes such as electrodialysis, reverse osmosis, diffusion dialysis, membrane electrolysis, fuel cells and ion exchange bioreactors. aim of this paper the experimental determination electrolyte following membranes: MK-40 membrane, Nafion N324 117 membrane. latter selected being a reference effect an increase...

We study the influence of an external electromagnetic field $1.8\phantom{\rule{0.3em}{0ex}}\mathrm{GHz}$ in formation or disaggregation long rouleau identical erythrocyte cells. In particular we calculate variation transmembrane potential individual illuminated by due to presence neighboring erythrocytes rouleau, and compare total electric energy isolated cells with rouleau. show that polarization plays a fundamental role cell system, consequently

Abstract Ion beam sputtering is a solid-surface nanostructuring procedure applicable to any type of material. In this study, we are interested in the bombardment metallic surface, specifically, Co(110) surface bombarded with Ar clusters at oblique incidence. The accentuates effect ripple formation. Sputter erosion and atomic redistribution processes that determine morphological evolution from collisional point view. importance these was analyzed for different angles incidence very small...

Abstract In this article, the transmembrane voltage induced on erythrocyte, codocyte, ovalocyte and spherocyte cell models exposed to a linearly polarised electromagnetic plane wave of frequency 1800 MHz is calculated. For purpose, finite element (FE) numerical technique with adaptive meshing used. The results show that value original erythrocyte shape higher than one observed rest altered geometries studied. membrane electric permittivity are shown play fundamental role values voltage....

We present simple parametric equations in terms of Jacobi elliptic functions that provide a realistic model abnormal variations size which maintain the biconcave shape normal erythrocyte (anisocytosis) and original volume (poikilocytosis), as well continuous deformations from to altered shapes. illustrate our results with parameterizations microcytes, macrocytes, stomatocytes, we apply these numerical calculation induced transmembrane voltage stomatocytes exposed an external electromagnetic...

We show that within the dipole approximation complex polarizability of shelled particles arbitrary shape can be written as volume particle times a weighted average electric field in particle, with weights determined by differences permittivities between shells and external, possibly lossy media. To calculate we use an adaptive-mesh finite-element method which is very effective handling irregular domains, material inhomogeneities, boundary conditions usually found biophysical applications....

Thermal conductivity of a material is critical parameter for using it in non-isothermal applications. The new emphasis on ion-exchange membranes as thermoelectric materials makes necessary to study the relation between thermal and structure properties. Here, through-plane different polymeric was measured by rapid experimental method simple Lee's Disc apparatus. Membranes with structures thicknesses interval 25–700 micrometers were analysed aim testing feasibility this kind samples....

We have studied the influence of anisotropic and dispersive nature red blood cell structure on energy absorption electric field distribution within exposed to electromagnetic fields frequencies in range from 50 kHz 10 GHz. For this purpose we generated a realistic model multilayered erythrocyte set parametric equations terms Jacobi elliptic functions. The effect dipole relaxations conductivities is taken into account dispersion for conductivity permittivity each layer (cytoplasmic...