Transgenic plants as a model for studying еpigenetic regulation of gene expression

The phenomenon of loss of expression of transferred genes in transgenic plants was discovered in the early 1990s. The study of this phenomenon revealed dependence of the frequency of gene silencing on the number of integrated copies in the plant genome, the properties of the transgene sequence itself (the presence of duplications, vector sequences, and others), chromosomal position. Loss of gene expression can occur transcriptionally or post-transcriptionally in most cases involving small interfering RNA (siRNA). In plants, the most common mechanism for inactivation of genes at the level of RNA transcription is RNA-directed DNA methylation (RdDM). An important role is played by the plant-specific RNA polymerase IV and V. Pol IV is assumed to transcribe non-coding transcripts at its target loci. They are copied into long dsRNAs and are processed by DICER into siRNAs. siRNAs are then methylated and loaded into the effector complex, whose main component is a protein of the Argonaute family. RNA polymerase V also transcribes the noncoding transcript of the target gene, but it serves as a scaf¬fold that interacts with siRNAs and that recruits proteins and enzymes responsible for DNA and histone methylation. Posttranscriptional gene inactivation occurs in the cytoplasm and is associated with a specific effector complex (AGO-siRNA), which cleavages homologous mRNA. In plants, in addition to the canonical pathway, RdDM, more mechanisms exist, which include components for posttranscriptional gene inactivation, specific proteins and other types of small RNAs. In this review, we briefly discuss the currently known components of epigenetic regulation

The role of copper in bifacial CdTe based solar cells

We present an innovative back contact for CdTe solar cell by the application of a transparent conducting oxide, typically ITO, as a back electrical contact on CdTe/CdS photovoltaic devices that acts as a free-Cu stable back contact and at the same time allows to realize bifacial CdTe solar cells, which can be illuminated from either or both sides. The controlled insertion of a very limited amount of copper into the ITO back contact permits to have reproducible devices with high efficiencies still keeping the bifacial configuration. Thin CdTe layer solar cells with ITO back contact have been realized with efficiencies exceeding 10%, the reduced thickness of CdTe allows to have a better performance on the back-side illumination and reduces the amount of CdTe material

Effect of feeding two-grain legumes, peas and faba beans, on egg quality and laying performances

Soymeal is now the main source of protein laying hens. This raw material is mainly produced abroad which makes Europe highly dependent on imports. A better protein autonomy could limit this economic impact and the environmental issue related to the cultivation of soybean. One of the options regularly studied over the past few decades to increase protein production in Europe is the cultivation of protein crops such as peas, faba beans and lupin. However, some inconvenient can limit their use in animal food as an alternative to soymeal, i.e., lower protein levels; presence of anti-nutritional factors; and non ideal amino acid profile. Therefore. te aim of this work was to assess the impact of using peas and faba beans as an alternative to soybean, on hens laying performances as well as on physical and nutritional eggs quality, including fatty acids profile. Two diets were tested, one containing only 22% of soymeal as proteins source (control group); and the second contains 45% of two leguminous plants (30% of peas and 15% faba beans) supplemented to 6% of soy meal. The egg-laying rate was significantly lower for the experimental group (51.79 vs. 60.63 %, p 0.05) was found concerning physical (egg weight, weight, shell weight and weight, shell thickness and strength), and nutritional parameters (cholesterol and essential fatty acids).La harina de soja es ahora la principal fuente de gallinas ponedoras de proteínas. Esta materia prima se produce principalmente en el extranjero, lo que hace que Europa dependa en gran medida de las importaciones. Una mejor autonomía proteica podría limitar este impacto económico y la cuestión ambiental relacionada con el cultivo de soja. Una de las opciones estudiadas regularmente en las últimas décadas para aumentar la producción de proteínas en Europa es el cultivo de cultivos proteicos como guisantes, habas de faba y lupin. Sin embargo, algunos inconvenientes pueden limitar su uso en alimentos animales como alternativa a la harina de soja, es decir, niveles más bajos de proteínas; presencia de factores anti-nutricionales; y perfil de aminoácidos no ideal. por lo tanto. El objetivo de este trabajo era evaluar el impacto del uso de guisantes y frijoles faba como alternativa a la soja, en las prestaciones de puesta de gallinas, así como en la calidad de los huevos físicos y nutricionales, incluido el perfil de ácidos grasos. Se probaron dos dietas, una que contiene sólo el 22% de la harina de soja como fuente de proteínas (grupo de control); y la segunda contiene el 45% de dos plantas leguminosas (30% de guisantes y 15% de habas de faba) complementadas al 6% de la harina de soja. La tasa de puesta de huevos fue significativamente menor para el grupo experimental (51,79 frente a 60,63 %, p 0,05) con respecto al físico (peso del huevo, peso, peso y peso de la cáscara, grosor y fuerza de la cáscara), y parámetros nutricionales (colesterol y ácidos grasos esenciale

Group up to learn together: a system for equitable allocation of students to groups

Group-based learning is overwhelmingly accepted as an important feature of current education practices. The success of using a group-based teaching methodology depends, to a great extent, on the quality of the allocation of students into working teams. We have modelled this problem as a vector packing problem and constructed an algorithm that combines the advantage of local search algorithms with the branch and bound methodology. The algorithm easily finds exact solutions to real life problems with about 130-150 students. The algorithm is implemented in GroupUp - a decision support tool which has been successfully used in the University of Warwick for a number of years

EXPRESSION OF A NEW A3 ANTIGEN IN THE CELLS OF PATIENTS WITH VARIOUS LYMPHOPROLIFERATIVE DISEASES

We have conducted a study of a novel monoclonal A3 antibody raised by means of hybridoma biotechnology. The study was performed with malignant cells of the patients with various lymphoproliferative disorders, and persons with nonmalignant diseases, as compared with intact lymphocytes from healthy people,using a method of immunocytochemical staining and indirect immunofluorescence technique. It was found that in cases of lymphoproliferative diseases with low proliferation rates, as based on the numbers of Ki-67 positive cells, as well as in non-malignant blood diseases, the A3 antigen was localized in nucleoli, and it was visualized as focal fluorescence. In malignant lymphoproliferative diseases with high proliferation indexes, the number of brightly fluorescent foci is observed, with formation of necklace-like structures within the nucleolar structures. The obtained data point to a diagnostic significance of A3 Mab in assessment of cellular proliferative rates in patients with various lymphoproliferative diseases. It was established that, in contrast to Ki-67, the proliferation stage could be determined for each cell, according to the number of fuorescent foci in nucleoli. This specific property of the A3 antigen points to its significance for diagnostics and malignancy staging of lymphoproliferative disorders

Physical Education of Students in the Problematic Field of Social and Communicative Transformations of Present-day Society

Розділ присвячено дослідженню фізичного виховання студентів як складової проблемного поля соціально-комунікативних трансформацій сучасного суспільства. The chapter is devoted to the study of students’ physical education as a component of the problematic field of social and communicative transformations in the contemporary society

MODAL DYNAMICS APPROXIMATIONS OF CANTILEVERS UNDER PARTIAL FOLLOWER LOAD

Presented herein is a modified Galerkin discretization procedure for determining the qualitative dynamic behavior of elastic cantilevers with internal damping under partial follower step loading at their tips. For this strong nonlinear nonconservative system, the scheme proposed makes use of basic functions that are a product of nonlinear corrections of approximate linear shape functions. These corrected modes are computed in a way that all the nonlinear non-homogeneous boundary conditions of the actual problem are satisfied throughout the motion. Numerical results obtained using a two-mode approach are found to be in very good qualitative agreement with the finite element results presented in the literature, not only in the vicinity of the critical states, but also in remote unstable domains. The effect of variation of initial conditions is also investigated and the advantages of the proposed procedure compared with conventional ones are discussed. Further research is required for establishing its capabilities and the range of its applicability for a broader class of nonconservative dynamic problems

Borehole nuclear geophysical studies of near-surface rocks. 1

On the basis of complex use of neutron, density and gammaray logging are proposed new approaches to determine of petrophysical parameters of nearsurface rocks in zone aeration and in water saturated zone. By increase in number of determined parameters it is considerably expanded of informativity of radioisotope logging. Thanking of the complex of geophysical methods and to the correct account of features of sandyclay rocks it is raised reliability and accuracy of determinations of humidity, porosity, density of dry rock, density of a solid phase, shaliness, the content of chemically bound water and other parameters