Time filter

Source Type

Blagoevgrad, Bulgaria

The South-West University "Neofit Rilski" is a university located in Blagoevgrad, Bulgaria. It was founded in 1975. Wikipedia.

Hubenova Y.,Plovdiv University | Mitov M.,South-West University | Mitov M.,Bulgarian Academy of Science

Various prokaryote species have been widely studied for microbial fuel cell (MFC) application. However, the information about yeast utilization into biofuel cells is still scanty. The aim of this investigation is to verify if Candida melibiosica 2491, a yeast strain, possessing high phytase activity, could be applied as a biocatalyst in a yeast biofuel cell. The microbiological requirements were coupled with the electrochemical ones tracing main biochemical pathway metabolites such as different carbohydrate and inorganic phosphates and their assimilation with time. The obtained results show that from the three carbohydrates investigated - glucose, fructose and sucrose, fructose is the most suitable for the yeast cultivation. The presence of yeast extract and peptone improves the performance into the biofuel cell. The relationship between the yeast cell amount and the biofuel cell characteristics was determined. Analyses showed that electricity was generated by the yeast culture even in the absence of an artificial mediator. The addition of methylene blue at concentrations higher than 0.1 mM improves the current and power density output. The obtained experimental results proved that C. melibiosica 2491 belongs to the electrogenic strains. © 2009 Elsevier B.V. All rights reserved. Source

A distortion of the aromatic character as a result of the Npy protonation of 2-aminopyridine was established by conventional and linear-polarized IR-spectroscopy, UV- and 1H-NMR-spectral analysis of model system 2-aminopyridinium tetrachlorocuprate (II) salt. Quantum chemical ab initio calculations are performed at MP2 and B3LYP levels of theory and 6-311 ++G** basis set in order to determine the changes in the geometrical parameters and IR-spectroscopic characteristics as a result of Npy protonation. The observed crystallochromy effect is discussed as well. © Springer Science+Business Media, LLC 2009. Source

Hubenova Y.,Plovdiv University | Mitov M.,South-West University

In the present study we demonstrate for the first time the possibility for conversion of solar energy into electricity on the principles of Direct Photosynthetic Plant Fuel Cell (DPPFC) technology by using aquatic higher plants. Lemna minuta duckweed was grown autotrophically in specially constructed fuel cells under sunlight irradiation and laboratory lighting. Current and power density up to 1.62±0.10A.m-2 and 380±19mW.m-2, respectively, were achieved under sunlight conditions. The influence of the temperature, light intensity and day/night sequencing on the current generation was investigated. The importance of the light intensity was demonstrated by the higher values of generated current (at permanently connected resistance) during daytime than those through the nights, indicating the participation of light-dependent photosynthetic processes. The obtained DPPFC outputs in the night show the contribution of light-independent reactions (respiration). The electron transfer in the examined DPPFCs is associated with a production of endogenous mediator, secreted by the duckweed. The plants' adaptive response to the applied polarization is also connected with an enhanced metabolism resulting in an increase of the protein and carbohydrate intracellular content. Further investigations aiming at improvement of the DPPFC outputs and elucidation of the electron transfer mechanism are required for practical application. © 2012 Elsevier B.V. Source

This article provides an overview of student training programs in logopedics in Bulgaria, Greece, Macedonia, Poland and the Russian Federation. The data were collected using a special questionnaire developed by Söderpalm in 2006 and supplemented by the author. Bachelor's, master's and PhD programs in the field of pure logopedics no longer exist in some countries. In other locations, logopedics is included as a part of special education student training. In all cases, student education in logopedics is centralized in the universities. Educational programs are accredited by national agencies for accreditation or evaluation or by the respective Ministries of Education. Copyright © 2010 S. Karger AG, Basel. Source

Umulis D.M.,South-West University | Shimmi O.,University of Helsinki | O'Connor M.B.,Howard Hughes Medical Institute | Othmer H.G.,University of Minnesota
Developmental Cell

Advances in image acquisition and informatics technology have led to organism-scale spatiotemporal atlases of gene expression and protein distributions. To maximize the utility of this information for the study of developmental processes, a new generation of mathematical models is needed for discovery and hypothesis testing. Here, we develop a data-driven, geometrically accurate model of early Drosophila embryonic bone morphogenetic protein (BMP)-mediated patterning. We tested nine different mechanisms for signal transduction with feedback, eight combinations of geometry and gene expression prepatterns, and two scale-invariance mechanisms for their ability to reproduce proper BMP signaling output in wild-type and mutant embryos. We found that a model based on positive feedback of a secreted BMP-binding protein, coupled with the experimentally measured embryo geometry, provides the best agreement with population mean image data. Our results demonstrate that using bioimages to build and optimize a three-dimensional model provides significant insights into mechanisms that guide tissue patterning. © 2010 Elsevier Inc. All rights reserved. Source

Discover hidden collaborations