The theory of elasticity is a very important discipline which has a lot of applications in science and engineering. In this paper we are interested in elastic materials with different properties between interfaces implicated the discontinuous coefficients in the governing elasticity equations. The main aim is to develop a practical numerical scheme for modeling the behaviour of a simplified piecewise homogeneous medium subjected to an external action in 2D domains. Therefore, the discontinuous Galerkin method is used for the simulation of elastic waves in such elastic materials. The special attention is also paid to treatment of boundary and interface conditions. For the treatment of the time dependency the implicit Euler method is employed. Moreover, the limiting procedure is incorporated in the resulting numerical scheme in order to overcome nonphysical spurious overshoots and undershoots in the vicinity of discontinuities in discrete solutions. Finally, we present computational results for two-component material, representing a planar elastic body subjected to a mechanical hit or mechanical loading.
The fads2 gene encoding Δ6-desaturase, the rate-limiting enzyme of the LCPUFA biosynthesis is expressed in astrocytes. Dietary fatty acids, which cross the blood-brain barrier, may regulate the transcription of lipogenic enzymes through activation of transcription factors such as peroxisome proliferator-activated receptors (PPARs). The PPARs form the transcription complex with retinoid X receptors (RXRs) that are activated by 9-cis retinoic acid, a metabolite of vitamin A (VA). The study examines whether challenge of astrocytes with VA, prior 24-h treatment with palmitic acid (PA), α-linolenic acid (ALA) or docosahexaenoic acid (DHA) has the effect on the FADS2 expression. RT-qPCR showed that in astrocytes not challenged with VA, PA increased fads2 gene expression and DHA decreased it. However, in VA-primed astrocytes, PA doubled the FADS2 mRNA levels, while DHA increased fads2 gene expression, oppositely to non-primed cells. Furthermore, similar changes were seen in VA-primed astrocytes with regard to Δ6-desaturase protein levels following PA and DHA treatment. ALA did not have any effect on the FADS2 mRNA and protein levels in either VA-primed or non-primed astrocytes. These findings indicate that in the presence of vitamin A, DHA upregulates fads2 gene expression in astrocytes., B. Dziedzic, D. Bewicz-Binkowska, E. Zgorzynska, D. Stulczewski, L. Wieteska, B. Kaza, A.Walczewska., and Obsahuje bibliografii
The Natal multimammate mouse, Mastomys natalensis, occurs throughout sub-Saharan Africa. Mitochondrial phylogenetics indicate this species was fragmented during the Pleistocene, forming six matrilineage phylogroups: A-I, A-II, A-III, B-IV, B-V, B-VI with distinct ranges. All except the A-III lineage are identified as natural reservoirs of mammarenaviruses. M. natalensis A-III is found in western Ethiopia and is the only lineage reported in the country. While screening 203 small mammal samples from Dhati Welel National Park for mammarenaviruses, we detected mammarenavirus RNA in nine samples, eight from M. natalensis and one from M. awashensis. A sequence similarity search and phylogenetic analysis confirmed the M. natalensis mitochondrial DNA belongs to the A-III lineage. We characterised the complete virus genome, which showed typical mammarenavirus organisation. Phylogenetic analysis indicated it clusters with Gairo virus found in M. natalensis B-IV in Tanzania, while showing sufficient divergence from other mammarenaviruses to be considered as a new species, for which we proposed the name Dhati Welel. Additional sampling in the M. natalensis A-III phylogeographic range should help determine whether the detection of the virus in M. awashensis represents a local spill-over or if the virus circulates in both Mastomys species.
The aim of our work was to provide data from women of fertile age with type 1 diabetes mellitus about the endogenous androgens and on their relations to the parameters of diabetes control. Forty-two women were examined, they did not use contraceptives for at least three months prior to the examination. A multivariate regression analysis showed that the daily insulin dose, the fasting glycemia and the HbA1c values and patient´s age correlated negatively with dehydroepiandrosterone sulfate, dehydroepiandrosterone and prolactin levels. The testosterone/ dehydroepiandrosterone sulfate ratio correlated positively with daily insulin dose and patient´s age. In contrast to adrenal androgens the values of other hormones, including total and free testosterone, androstenedione, dihydrotestosterone, estradiol, LH, FSH, 17-OH-P, progesterone and cortisol revealed no significant correlation. To conclude, significant relations between the glucose control parameters and the adrenal androgens and prolactin were demonstrated. These relationships should be considered as an important factor influencing diabetes control so the additional cardiovascular risk in women with DM1., H. Kvasnickova, R. Hampl, K. Vondra., and Obsahuje bibliografii