Tangent developable surfaces elements in thinwalled structures

This report demonstrates the capabilities of an advanced research area of the applied mathematics, i.e., computational geometry to be applied for shaping dimensional structures. Vector-matrix models are provided to purpose of piecewise-smooth structures modelling by surface elements with zero Gaussian curvature (elements of developable surfaces). The elements of tangent developable surfaces can be built on the directing curves pieces located arbitrarily in space. The paper presents an analytical algorithm for drawing a cutting for the tangent developable surface element with two specified directing curves and the edge of regression known. An analytic algorithm for the curve on tangent developable surface development via the parametric equations of the edge of regression and the curveitself is obtained based on the tangent developable surface edge of regression development algorithm

Optimisation model for industrial complex competitiveness: A path to sustainable innovation process

Business entities of all forms and origin face the necessity to foster new management approaches in order to promote its excellence. Sustainability is a key issue for organisations nowadays as they increasingly acknowledge that their practices have social and/or environmental consequences. Multi-stakeholder systems such as industrial complexes/clusters seek to raise competitiveness by integrating new innovative business models and appropriate responsibility in various fields of operations. These managerial technologies require a novel outlook at the optimisation model of the numerous competitive forces and its evaluation. In light of this, it is imperative that new methodologies and frameworks to facilitate the understanding of sustainability concepts in the business environment are to be developed as innovation approach. The framework suggested in the paper helps to outline guidelines on evaluating the nature and process of innovative and sustainable competitive strategy considering many indicators influencing industrial complexes and its environment. Copyright © 2016 Inderscience Enterprises Ltd

Mitochondrial Electron Transport Chain in Heavy Metal-Induced Neurotoxicity: Effects of Cadmium, Mercury, and Copper

To clarify the role of mitochondrial electron transport chain (mtETC) in heavy-metal-induced neurotoxicity, we studied action of Cd2+, Hg2+, and Cu2+ on cell viability, intracellular reactive oxygen species formation, respiratory function, and mitochondrial membrane potential of rat cell line PC12. As found, the metals produced, although in a different way, dose- and time-dependent changes of all these parameters. Importantly, Cd2+ beginning from 10 [mu]M and already at short incubation time (3 h) significantly inhibited the FCCP-uncoupled cell respiration; besides, practically the complete inhibition of the respiration was reached after 3 h incubation with 50 [mu]M Hg2+ or 500 [mu]M Cd2+, whereas even after 48 h exposure with 500 [mu]M Cu2+, only a 50% inhibition of the respiration occurred. Against the Cd2+-induced cell injury, not only different antioxidants and mitochondrial permeability transition pore inhibitors were protective but also such mtETC effectors as FCCP and stigmatellin (complex III inhibitor). However, all mtETC effectors used did not protect against the Hg2+- or Cu2+-induced cell damage. Notably, stigmatellin was shown to be one of the strongest protectors against the Cd2+-induced cell damage, producing a 15–20% increase in the cell viability. The mechanisms of the mtETC involvement in the heavy-metal-induced mitochondrial membrane permeabilization and cell death are discussed

Symbolic-numeric approach for solving linear differential equations of the fourth order

This paper presents a symbolic-numeric approach for solving linear differential equations of the fourth order in the form of generalized power series. The working program allows to find solutions to differential equations of the fourth order in the form of power series, generally, of any order, but is limited by capabilities of a given computer. Some examples of solving differential equations of the fourth order are presented, which show the efficiency of the developed progra

Cardiac fibroblasts mitochondrial activity in the presence of medicinal preparations with various pharmacological effects

The studies of cardiac fibroblasts mitochondria activity using fluorescence probe MitoTracker Red CMXRos (Thermo Fisher Scientific, USA) and proliferation capacity with MTT assay (Thermo Fisher Scientific, USA) were carried out under the influence of antihypoxant (trimetazidine) and anticancer (doxorubicin, cytosar) medicinal preparations. It was revealed that medicinal preparations from the antitumor antibiotics group decreased mitochondria activity regardless of the cell state unlike antitumor metabolites. Medicinal preparation trimetazidine increases cardiac fibroblasts mitochondrial activit

Polymorphism of gene glutathion-s-transferase pi in teenagers from Buryat ethnic group living in the Irkutsk region

Background. Human glutathione-S-transferases play an important role in phase II detoxification process. But polymorphism in the GSTP1 gene has not been studied in certain populations. Aim: to determine the distribution of allele and genotype frequencies of GSTP1 gene in teenagers from Buryat ethnic group. Materials and methods. Blood samples were obtained from 55 teenagersfrom Buryat ethnic group. There were 28 males and 27 females with an age of 14.05 ± 0.99 years over the range of 13 to 16. DNA was isolated from blood samples. The polymerase chain reaction was used to amplify A313G and C341T markers of the GSTP1 gene. Chi-square testing was used to evaluate the significant difference of the GSTP1 genotype frequencies between observed and expected values. Results. Allele and genotype frequencies of A313G and C341T markers GSTP1 were determined in teenagers from Buryat ethnic group. The study showed that the frequencies of A and G alleles at the A313G marker were 0.809 and 0.191 while those of C and T alleles at the C341T marker were 0.973 and 0.027, respectively. The distribution of the genotype frequencies at the A313G marker were consistent with expected in a Hardy - Weinberg equilibrium (χ2 = 0.77; d.f. = 1; p > 0.05). However, the distribution of the genotype frequencies at the C341T marker were not consistent with expected in a Hardy - Weinberg equilibrium (χ2 = 0.043; d.f. = 1; p < 0.05). It was because the homozygous of T allele was not found in the ethnic group of Buryat