Microscopic Model of Charge Carrier Transfer in Complex Media

We present a microscopic model of a charge carrier transfer under an action of a constant electric field in a complex medium. Generalizing previous theoretical approaches, we model the dynamical environment hindering the carrier motion by dynamic percolation, i.e., as a medium comprising particles which move randomly on a simple cubic lattice, constrained by hard-core exclusion, and may spontaneously annihilate and re-appear at some prescribed rates. We determine analytically the density profiles of the "environment" particles, as seen from the stationary moving charge carrier, and calculate its terminal velocity as the function of the applied field and other system parameters. We realize that for sufficiently small external fields the force exerted on the carrier by the "environment" particles shows a viscous-like behavior and define an analog of the Stokes formula for such dynamic percolative environments. The corresponding friction coefficient is also derived.Comment: appearing in Chem. Phys. Special Issue on Molecular Charge Transfer in Condensed Media - from Physics and Chemistry to Biology and Nano-Engineering, edited by A.Kornyshev (Imperial College London), M.Newton (Brookhaven Natl Lab) and J.Ulstrup (Technical University of Denmark

Determination of diffusion coefficients of glycerol and glucose from starch based thermoplastic compounds on simulated physiological solution

Blends of corn starch with poly(ethylene-vinylalcohol) copolymer (SEVA-C) have been studied and reported as biodegradable. These materials are known to be sensitive to enzymatic action, evidencing a degradation of the starch phase in α-amylase assays. However, from the physical-chemical point of view the degradation of the blend is mainly associated with the leaching of glycerol, since other compounds are not released and no carbohydrates were found in the degradation solution. Based on these results, the present work attempts to determinate the respective diffusion coefficients. Four different experiments were performed, using samples with different thicknesses that were immersed in a simulated physiological solution. High performance liquid chromatography (HPLC) was used to separate the sugar derivatives and glycerol from the degradation solutions. The obtained data were fitted to an empirical model to allow the estimation of the diffusion coefficient for glycerol and glucose, based on the analytical solution for Fick’s law of diffusion, and a good agreement was found (R² ≈ 1). The glycerol leaches quickly out during the first few days of immersion, stabilizing thereafter, presenting greater diffusion coefficients for thicker samples. As the quantity of saccharides in the solution remains almost invariable along the experiments, this work also confirms that the degradation process is difficult without the action of enzymes

Magnetic Modulation in Mechanical Alloyed Cr1.4fe0.6o3 Oxide

We have synthesized Cr1.4Fe0.6O3 compound through mechanical alloying of Cr2O3 and Fe2O3 powders and subsequent thermal annealing. The XRD spectrum, SEM picture and microanalysis of EDAX spectrum have been used to understand the structural evolution in the alloyed compound. The alloyed samples are matching to rhombohedral structure with R3C space group. The observation of a modulated magnetic order confirmed a systematic diffusion of Fe atoms into the Cr sites of lattice structure. A field induced magnetic behaviour is seen in the field dependence of magnetization data of the annealed samples. The behaviour is significantly different from the mechanical alloyed samples. The experimental results provided the indications of considering the present material as a potential candidate for opto-electronic applications.Comment: 8 figure

Band selection algorithms for foliar trait retrieval using AVIRIS-NG: a comparison of feature based attribute evaluators

Interband information overlapping enhances redundancy in hyperspectral data. This makes identification of application-specific optimal bands essential for obtaining accurate information about foliar traits. The current study investigated the performance of three novel Band Selection (BS) algorithms (i.e. the Chi-squared-statistics based attribute evaluator (CSS), the Recursive elimination of features-based attribute evaluator (REF) and the Correlation-based attribute subset evaluator (CBS)) in identifying the spectral bands of Airborne Visible/Infrared Imaging Spectrometer-Next Generation (AVIRIS-NG) from visible and Near Infrared (NIR) regions that are sensitive to variation in Chlorophyll Content (CC). Identified bands were employed to formulate Hyperspectral Indices (HIs) by incorporating combinations of Blue, Green, Red, and NIR regions. CC models were built by establishing a linear fit between ground CC and HIs. For all the three BS algorithms, optimum bands varied for visible and NIR regions. REF-HI (NIR,R), REF-HI(NIR,R + G), CSS-HI(NIR,R) and CSS-HI(NIR,R + G) had the best correlation with CC. HI(NIR,R) is identified as the best HI and REF the best BS algorithm for retrieving CC

Not Available

The article Received 11 August 2016 Revised 11 September 2016 Accepted 16 September 2016 PublishYak is an iconic symbol of Tibet and high altitudes of Northeast India. It is highly cherished for milk, meat, and skin. However, yaks suffer drastic change in milk production, weight loss, etc, when infested by parasites. Among them, infestation by leeches is a serious problem in the Himalayan belt of Northeast India. The parasite feeds on blood externally or from body orifices, like nasopharynx, oral, rectum, etc. But there has been limited data about the leech species infesting the yak in that region because of the difficulties in morphological identification due to plasticity of the body, changes in shape, and surface structure and thus, warrants for the molecular characterization of leech. In anticipation, this study would be influential in proper identification of leech species infesting yak track and also helpful in inventorying of leech species in Northeast India. Here, we investigated, through combined approach of molecular markers and morphological parameters for the identification of leech species infesting yak. The DNA sequences of COI barcode fragment, 18S and 28S rDNA, were analyzed for species identification. The generated sequences were subjected to similarity match in global database and analyzed further through Neighbour-Joining, K2P distance based as well as ML approach. Among the three markers, only COI was successful in delineating species whereas the 18S and 28S failed to delineate the species. Our study confirmed the presence of the species from genus Hirudinaria, Haemadipsa, Whitmania, and one species Myxobdella annandalae, which has not been previously reported from this region.Department of Biotechnology, Government of Indi

Not Available

Not AvailableGenetic assessment of leech species from yak (Bosgrunniens) in the tract of Northeast India.Not Availabl

Genetic assessment of leech species from yak (<i>Bos grunniens</i>) in the tract of Northeast India

<p>Yak is an iconic symbol of Tibet and high altitudes of Northeast India. It is highly cherished for milk, meat, and skin. However, yaks suffer drastic change in milk production, weight loss, etc, when infested by parasites. Among them, infestation by leeches is a serious problem in the Himalayan belt of Northeast India. The parasite feeds on blood externally or from body orifices, like nasopharynx, oral, rectum, etc. But there has been limited data about the leech species infesting the yak in that region because of the difficulties in morphological identification due to plasticity of the body, changes in shape, and surface structure and thus, warrants for the molecular characterization of leech. In anticipation, this study would be influential in proper identification of leech species infesting yak track and also helpful in inventorying of leech species in Northeast India. Here, we investigated, through combined approach of molecular markers and morphological parameters for the identification of leech species infesting yak. The DNA sequences of <i>COI</i> barcode fragment, <i>18S</i> and <i>28S rDNA,</i> were analyzed for species identification. The generated sequences were subjected to similarity match in global database and analyzed further through Neighbour-Joining, K2P distance based as well as ML approach. Among the three markers, only <i>COI</i> was successful in delineating species whereas the <i>18S</i> and <i>28S</i> failed to delineate the species. Our study confirmed the presence of the species from genus <i>Hirudinaria, Haemadipsa</i>, <i>Whitmania,</i> and one species <i>Myxobdella annandalae,</i> which has not been previously reported from this region.</p