Bulk-sensitive Photoemission of Mn5Si3

We have carried out a bulk-sensitive high-resolution photoemission experiment on Mn5Si3. The measurements are performed for both core level and valence band states. The Mn core level spectra are deconvoluted into two components corresponding to different crystallographic sites. The asymmetry of each component is of noticeable magnitude. In contrast, the Si 2p spectrum shows a simple Lorentzian shape with low asymmetry. The peaks of the valence band spectrum correspond well to the peak positions predicted by the former band calculation.Comment: To be published in: Solid State Communication

Генетические и эпигенетические механизмы регуляции вирусов папиллом человека

Infections with high-risk human papillomaviruses (HPV) are the etiological factor of certain types of human cancers in anogenital tract and head and neck cancers. Extensive epidemiological studies demonstrated the association of persistent high-risk HPV infection and the later development of cervical and other cancers. Experimental data using cell lines models and cervical cancers demonstrate that in more than 99 % of clinical samples the viral E6 and E7 genes are retained and expressed. These genes can transform human cells and inhibition of their expression in cancer cells results in loss of neoplastic growth properties. Molecular mechanisms of immortalization and transformation by E6 and E7 have extensively been investigated. However, the mechanism of E6 and E7 deregulation that triggers the shift from permissive infection to neoplastic transforming infection is still unclear. This review describes the current knowledge about the viral life cycle and discusses the molecular mechanisms that potentially allow the virus to escape its normal control and may trigger neoplastic progression. The molecular clarification of these events required for transformation of HPV-infected cells into cancer will provide a basis for conceptually novel diagnostic and therapeutic strategies and approaches.Инфекция вирусом папиллом человека (human papillomavirus, HPV) высокого канцерогенного риска является этиологическим фактором некоторых видов опухолей аногенитальной области и опухолей головы и шеи. Многочисленные эпидемиологические исследования показали связь длительно персистирующей инфекции HPV высокого канцерогенного риска с последующим развитием рака шейки матки и опухолей других локализаций. Экспериментальные данные с использованием цервикальных клеточных моделей и клинических образцов опухолей шейки матки продемонстрировали, что более чем в 99 % клинических образцов рака шейки матки вирусные онкогены Е6 и Е7 сохраняются и экспрессируются. Вирусные онкогены могут трансформировать кератиноциты в экспериментах in vitro; их ингибирование приводит к подавлению неопластического роста клеток. Молекулярные механизмы иммортализации и трансформации вирусными онкогенами Е6 и Е7 достаточно хорошо исследованы. Однако остаются неясными механизмы дерегуляции экспрессии вирусных онкогенов, приводящие к переходу от продуктивного вирусного цикла к трансформации плоскоклеточного эпителия. В настоящем обзоре описано современное представление о продуктивном вирусном цикле и обсуждаются потенциальные молекулярные механизмы, вызывающие инициацию процесса трансформации нормального эпителия в неопластические предраковые поражения. Выяснение молекулярных механизмов, необходимых для неопластической трансформации HPV-инфицированных нормальных клеток в опухолевые, может предоставить основу для концептуально новых терапевтических подходов лечения HPV-ассоциированных опухолей

Ways to control asynchronous motor with phase rotor of mining machines

The article describes various methods of controlling asynchronous motors with a phase rotor. To solve the problems of controlling speeds and moments in a modern electric drive, two main methods of frequency control are used: scalar and vector. Advantages and disadvantages of scalar and vector control, voltage dependence are given

T35 Epigenetic changes in human cervical carcinomas associated with viral induced pathogenesis

Epigenetics investigates mechanisms that control inheritance of gene expression program during somatic cell divisions. These mechanisms include regulation by DNA methylation, histone post-translational modifications and nucleosome positioning, functioning of regulatory non-coding RNAs, control of alternative splicing of mRNA precursors and high-order chromatin organization. Genome-wide loss of epigenetic stability and increased epigenetic plasticity are common features of all tumor types. In normal tissues epigenetic plasticity allow cells to response on environment signals. Thus, in tumor cells its constitutive activation leads to epigenetic heterogeneity that are the additional hallmark of the most of the classical cancers. Cervical cancers are one of the most interesting models for the analysis of the role of epigenetic changes in tumor progression. These types of tumors are associated with infection of human papilloma viruses of so-called high-risk group (HR-HPV) and characterized by well-defined stages of malignant conversion from intraepithelial neoplasias to carcinomas. The viral DNA can persist in episomal form or integrates into the host-cell genome.Cellular genomes encode genetic information in their linear sequence, but appropriate gene expression requires chromosomes to fold into dynamic complex three-dimensional structures. Scaffold/matrix attachment regions (S/MARs) are specialized genomic DNA sequences that take part in organization of these structures. We demonstrated that methylation of S/MARs was required for their attachment to nuclear matrix and that methylation status of S/MARs was changed in cervical cancer cell compared to normal cells.DNA methylation plays an important role in the regulation of gene expression. We found that methylation of the regulatory sequences in the HPV16 genome specifically changes in transformed compared to the normal cervical epithelial cells. Next, we showed that methylation of the transcription factor binding sites modulates the viral oncogene expression. These data suggest that the HPV16 genome methylation may represent an important mechanism that initiates the development of HPV-associated tumors.Using next generation sequencing, we identified pattern of differentially expressed microRNAs in clinical samples of the cervical lesions. We confirmed expression of microRNAs that have been described previously as well as identified new microRNAs that can be potentially involved in the development and progression of cervical cancer. Spectrum of differentially expressed microRNAs includes microRNAs targeting tumor-suppressor genes as well as oncogenes.Telomerase is a key regulator of cell proliferation. This enzyme is silent in normal cells and activated in most of the tumors. Few forms of RNA (hTERT), encoded by telomerase gene were detected in different tumor cells and among them three forms (alfa, beta and gamma) are most well pronounced. We found that in cervical tumors expression of all three forms are significantly increased. In some cases, we also observe higher level of hTERT expression in neighboring “normal tissue”. The correlation between expression levels of these three forms varied on different stages of the disease (three stages on intraepithelial neoplasias and carcinomas). The function of these three hTERT forms is still not well understood

Spin Polarization and Magneto-Coulomb Oscillations in Ferromagnetic Single Electron Devices

The magneto-Coulomb oscillation, the single electron repopulation induced by external magnetic field, observed in a ferromagnetic single electron transistor is further examined in various ferromagnetic single electron devices. In case of double- and triple-junction devices made of Ni and Co electrodes, the single electron repopulation always occurs from Ni to Co electrodes with increasing a magnetic field, irrespective of the configurations of the electrodes. The period of the magneto-Coulomb oscillation is proportional to the single electron charging energy. All these features are consistently explained by the mechanism that the Zeeman effect induces changes of the Fermi energy of the ferromagnetic metal having a non-zero spin polarizations. Experimentally determined spin polarizations are negative for both Ni and Co and the magnitude is larger for Ni than Co as expected from band calculations.Comment: 4 pages, 3 figures, uses jpsj.sty, submitted to J. Phys. Soc. Jp

Hydrological regime of Molochnyi liman under anthropogenic and natural drivers as a basis for management decision-making

Molochnyi Liman is the largest liman (22,000 ha) at the northern coast of the Sea of Azov. Contrary to estuaries, it is an ecotone without typical tides. It is a half-closed water body, with a connection to the Sea of Azov that has periodically renewed or ceased over the course of time. Molochnyi Liman is a wetland of international importance, a hydrological reserve of state significance and is part of the Pryazovskyi National Natural Park. The results of our research have established that termination of the liman/sea connection has led to significant hydrological changes. The most crucial is a reduction in the liman’s depth, accompanied with shrinkage in the water surface area, a dramatic increase in salinity to 95 g/l and the loss of several Ramsar criteria. Restoration of the Molochnyi Liman ecosystem requires a positive water balance. There is a need for ensuring the inflow of at least 100 mln m3 of marine water into the liman through a connecting channel. This will renew normal functioning of the liman and reduce the salinity to an optimal level. The methodical approach used in this work can also be applied to other closed and half-closed water bodies of the Azov-Black Sea Region. The development of a hydrological model can be effectively used as a supportive tool for the management of the Tylihulskyi, Khadzhibeiskyi and Kuyalnytskyi limans in the north-western part of the Black Sea

European experience of human resources development for micro business: relevance and implementation algorithm for the republic of Moldova

Значна частина мікропідприємств Євросоюзу являє собою самозайняті підприємства або підприємців. У країнах ЄС-28 самозайнятих підприємств, які мають 0% найманих робітників і становлять 56% від усього сектору малого та середнього бізнесу. Європейські експерти приділяють багато уваги зміцненню і розвитку даного сектора економіки. У всіх країнах ЄС організовані програми для підтримки діяльності самозайнятих підприємців, багато з яких були б корисні до впровадження в Республіці Молдова. У Молдові схожі характеристики мають мікропідприємства, які відносяться до сектору малого та середнього бізнесу і займають 85,1% від загальної кількості підприємств малого бізнесу. Відповідно, у статті було проаналізовано програми розвитку мікробізнесу у країнах Європейського Союзу, враховуючи найбільш важливі для підприємців. Новизна і практична значимість статті обумовлені рекомендаціями, які включають алгоритм впровадження європейського досвіду програм розвитку самозайнятих підприємців в секторі малого бізнесу Молдови.Many of the EU-28 SMEs are run by self-employed micro enterprises. In the EU-28 self-employed enterprises with 0% of employees consist 56% of the SME. European experts attach great importance to the strengthening and development of this sector of the economy. All EU countries have organized programs to support the activities of self-employed entrepreneurs, many of which would be useful for implementation in the Republic of Moldova. In Moldova, microenterprises have similar characteristics, which belong to the small and medium-sized business sector and occupy 85.1% of the total number of small businesses. Accordingly, the article analyzes the programs of microbusiness development in the European Union, including the most important ones, according to the entrepreneurs opinians. The novelty and practical significance of the article are due to the recommendations, including the algorithm of implementation of the European experience of development programs for self-employed entrepreneurs in the SME sector of Moldova.Значительная часть микропредприятий Евросоюза представляет собой самозанятые предприятия или предпринимателей. В странах ЕС-28 самозанятые предприятия, имеющие 0% наемных рабочих, составляют 56% от всего сектора малого и среднего бизнеса. Европейские эксперты придают большое значение укреплению и развитию данного сектора экономики. Во всех странах ЕС организованы программы для поддержки деятельности самозанятых предпринимателей, многие из которых были бы полезны к внедрению в Республике Молдова. В Молдове близкие характеристики имеют микропредприятия, которые относятся к сектору малого и среднего бизнеса и занимают 85,1% от общего числа предприятий малого бизнеса. Соответственно, в статье проанализированы программы развития микробизнеса в Европейском Союзе, включая наиболее важные, по мнению самих предпринимателей. Новизна и практическая значимость статьи обусловлены рекомендациями, включающими алгоритм внедрения европейского опыта программ развития самозанятых предпринимателей в секторе малого бизнеса Молдовы

The Red Data Book Waterbirds in the Coastal Wetlands of the Azov-Black Sea Region of Ukraine — the Results of the August Counts 2018 and 2021

The article analyses data from the August Counts of 2018 and 2021, which covered the 40 most important wetlands on the Azov-Black Sea coast of Ukraine. Of the 106 wetland bird species recorded during the censuses, 35 species are listed in the Red Data Book of Ukraine. The number of them was about 50 thousand individuals or 7.6 % of the total number of counted birds: in 2018 — 24.1 thousand individuals and in 2021 — 25.8 thousand individuals. Detailed information on the number of bird species and the list of the most important sites for each species can be found in the publication. The comparison of the current data with the previous survey period 2004‒2015 (Chernichko et al., 2018) showed that the abundance of 17 waterbird species decreased, and 7 species increased their abundance. It is assumed that these changes are caused by the aridification of the climate, leading to the drying out of the shallow parts of the region's wetlands in the second half of the summer

Magneto-Coulomb Oscillation in Ferromagnetic Single Electron Transistors

The mechanism of the magneto-Coulomb oscillation in ferromagnetic single electron transistors (SET's) is theoretically considered. Variations in the chemical potentials of the conduction electrons in the ferromagnetic island electrode and the ferromagnetic lead electrodes in magnetic fields cause changes in the free energy of the island electrode of the SET. Experimental results of the magneto-Coulomb oscillation in a Ni/Co/Ni ferromagnetic SET are presented and discussed. Possible applications of this phenomenon are also discussed.Comment: 24 pages Latex, 5 figures in GIF files, style files included. Revised version: some errors are corrected and further discussions are added. To be published in J. Phys. Soc. Jpn. Vol.67 (1998) No.

Assessment of the physical development of adolescents in the gymnasium N in Yekaterinburg: analysis of the results of cross-sectional study

The aim of study – to assess of the PD of students in grades 8–10 of the Gymnasium N in Yekaterinburg and compare with the PD of adolescents in regions of RussiaЦель исследования – оценка физического развития учащихся 8–10 классов Гимназии N города Екатеринбург и ее сравнение с ФР детей и подростков различных субъектов Росси