316 research outputs found
Использование эпифитных мхов для оценки загрязнения окружающей среды ртутью на примере окрестностей города Томска
Critical properties of the quantum Ashkin-Teller chain with chiral perturbations
We investigate the nature of the phase transitions in the quantum
Ashkin-Teller chain in the presence of chiral perturbations. We locate the
Lifshitz line separating a region of direct chiral transitions from the region
where the transition is through an intermediate floating phase. Furthermore, we
identify a small region in the vicinity of the four-state Potts point where
chiral perturbations are irrelevant and where the transition remains conformal.
Implications to Rydberg atoms experiments are briefly discussed.Comment: 6 Pages, 8 Figure
Regulation of the MAD1 promoter by G-CSF
MAD family proteins are transcriptional repressors that antagonize the functions of MYC oncoproteins. In particular, MAD1 has been demonstrated to interfere with MYC-induced proliferation, transformation and apoptosis. The MAD1 gene is expressed in distinct patterns, mainly associated with differentiation and quiescence. We observed that MAD1 is directly activated by G-CSF in promyelocytic cell lines. To investigate the transcriptional regulation of the human MAD1 gene, we have cloned and characterized its promoter. A region of high homology between the MAD1 orthologs of human, mouse and rat contains the core promoter, marked by open chromatin, high GC content and the lack of a TATA box. Using deletion constructs we identified two CCAAT-boxes occupied by C/EBPα and β in the homology region that mediate responsiveness to G-CSF receptor signaling. The necessary signals include the activation of STAT3 and the RAS/RAF/ERK pathway. STAT3 does not bind directly to promoter DNA, but is recruited by C/EBPβ. In summary, our studies provide a first analysis of the MAD1 promoter and suggest STAT3 functions as a C/EBPβ cofactor in the regulation of the MAD1 gene. Our findings provide the base for the characterization of additional signal transduction pathways that control the expression of MAD1
Оптимизация условий для контроля качества наполнителя в металлических трубках
Проанализирована возможность с помощью цифровой радиографии контролировать качество наполнителя в детонирующем шнуре с целью обнаружения разноплотных включений, разрывов и других технологических нарушений. Проанализированы закономерности изменений интенсивности прошедшего потока квантов в геометрии узкого пучка. Определена энергия рентгеновского излучения, обеспечивающая максимальный перепад интенсивности прошедшего потока при изменении плотности наполнителя на +-30 %
Utilization of combustible wastes in gel fuel compositions in the Arctic and Antarctic conditions
The influence of annealings on structure and microhardness of Fe-Mo-V-Nb-C steel processed by high-pressure torsion
The influence of high-pressure torsion on microstructure, microhardness and thermal stability of lowcarbon steel Fe-0,1Mo-0,6Mn-0,8Cr-0,2Ni-0,3Si-0,2Cu-0,1V-0,06Nb-0,09C, (wt.%) was investigated. It was shown that ultrafine-grained structure formed by high-pressure torsion possesses a high microhardness (H[mu]=7,0 GPa) and high thermal stability up to the temperature of 400°С
Tissue-specific expression of a FMR1/β-galactosidase fusion gene in transgenic mice
Fragile X syndrome is one of the most common genetic causes of mental retardation, yet the mechanisms controlling expression of the fragile X mental retardation gene FMR1 are poorly understood. To identify sequences regulating FMR1 transcription, transgenic mouse lines were established using a fusion gene consisting of an E.coli β-galactosidase reporter gene (lacZ) linked to a 2.8 kb fragment spanning the 5′-region of FMR1. Five transgenic mouse lines showed lacZ expression in brain, in particular in neurons of the hippocampus and the granular layer of the cerebellum. Expression of the reporter gene was also detected in Leydig cells and spermatogonia in the testis, in many epithelia of adult mice, and in the two other steroidogenic cell types, adrenal cortex cells and ovarian follicle cells. Embryonic tissues which showed strong activity of the reporter gene included the telencephalon, the genital ridge, and the notochord. This expression pattern closely resembles the endogenous one, indicating that the 5′ FMR1 gene promoter region used in this study contains most cis-acting elements regulating FMR1 transcriptio
Teaching Disciplines "History of Russia" and "Country Studies" to Foreign Students: Problems and Solutions
The present paper is focused on the problem of teaching foreign students such disciplines as "Country studies" and "History of Russia", which appear to be compulsory for the international students, getting higher education in Russia. Studying these disciplines, students meet some difficulties due to various reasons, beginning with poor knowledge of Russian language and ending with ethical problems. A lecturer needs to cross this socio-cultural and linguistic barrier and find solutions in order to give the full information in accordance with the educational working program. The research has an applied character. It is based on the sociological survey conducted among the foreign students of National Research Tomsk Polytechnic University. The aim of the paper is to demonstrate real difficulties of students and lecturers at studying and teaching disciplines "Country studies" and "History of Russia" and to offer solutions for overcoming these problems
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