997 research outputs found
The use of innovative assessment tools in the process of physical education students at the university
The article deals with the problem of fund formation evaluation meansВ статье рассматриваются проблемы формирования фонда оценочных средст
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
Conformation of unsymmetrical diaryl disulfides
1. In solution the unsymmetrical p-substituted diaryl disulfides have a skewed conformation with a dihedral angle of ∼80°. 2. The angles of rotation of the aryl fragments relative to the planes of the Car-S-S bonds in the molecules of different compounds depend on the nature of the p-substituents. © 1978 Plenum Publishing Corporation
Kerr constants and steric structure of acetylenic thio- and selenoethers
1. The axes of the polarizability ellipoids of the Csp-S and Csp-Se bonds were determined. 2. The steric structure of a number of acetylenic thio- and selenoethers p-XC6H4E-C≡CC6H5 was studied. The benzene ring attached to the triple bond is located in the plane of the {Mathematical expression} bonds, while the aromatic fragment attached to the heteroatom (S or Se) lies outside this plane by ∼30-40°. © 1979 Plenum Publishing Corporation
A conformational analysis of o,o'- and m,m'-disubstituted diphenyl disulfides and diselenides based on dipole moments and Kerr constants
Effective conformations have been established for the o,o'- and m,m'-disubstituted diaryl disulfides and diselenides. Angles of aryl group rotation relative to the C-E-E plane have been determined for these compounds. One of the substituents lies inside, and one outside, the C-E-E-C dihedral angle. © 1979 Plenum Publishing Corporation
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.
Diagnostics of the level of development of small students team of USMU
The article presents the results of questionnaire of 1-6 year students of different faculties of USMU for diagnostics of the level of development of a small team.в статье представлены результаты анкетирования обучающихся 1-6 курсов факультетов УГМУ на предмет диагностики уровня развития малой команд
Study of the interests of students of faculty of preventive medicine of USMU
The article presents the results of questionnaire of 1-3 year students of Faculty of Preventive Medicine of USMU about their interests in the learning process.в статье представлены результаты анкетирования интересов в процессе освоения образовательной программы обучающихся 1-3 курсов медико-профилактического факультета УГМУ об их учебном процесс
Контроль якості вимірювань альфа-, бета-лічильника з низьким фоном ALBA 2000 v.2.5.6.
The article provides a systematic approach to quality control of measurements of total alpha-and beta-activity using a counter with a low background ALPHA / BETA COUNTING SYSTEM ALBA (mod. ALBA / LLAB) and software ALBA 2000 v.2.5.6. The purpose is to determine the compliance of these objects with the requirements of regulatory documentation. The spectrometry method is based on the physical concentration of radionuclides from the sample volume, measuring the rate of alpha, and beta radiation of the obtained dry residue of the sample, comparing the sample count rate with calibration values of activity, and calculating the total alpha, beta activity of the sample. The primary means of testing is a counter with a low background ALPHA / BETA COUNTING SYSTEM ALBA 200, the lower limit of measurements of the alpha activity, which is 0.02 Bq/l, and beta activity of 0.1 Bq/l, the relative random uncertainty of the measurement result is 60 % with a confidence level P = 0.95. The efficiency of registration on the alpha channel of 43 %, background on the alpha channel of 0,11 imp./min, for a measurement time of 60,000 s, the efficiency of registration on the beta channel of 30 %, background on the beta channel of 1,9 imp./min, for measurement time 60000 s. As a comparison sample for calculating total alpha activity, a sample with alpha radiation, 241Am (geometry 2π), is used. To calculate the total beta activity, a sample of beta-emitter of potassium sulfate with radionuclide is used at 40K (geometry 2π). The weight of the counting sample ranges from 200 to 1000 mg. The activity values are calculated automatically, using the software ALBA 2000, v.2.5.6. Measurement of the total activity of radionuclides in counting samples using the method should be performed only in calibrated geometries. At the same time, the safety requirements, personnel qualifications, and test conditions must be met. Quality control of measurements in the alpha, beta counter ALBA-2000 v.2.5.6. It is carried out in qualitative and quantitative ways.У статті запропоновано системний підхід щодо контролю якості вимірювань сумарної альфа-, бета-активності із застосуванням лічильника з низьким фоном ALPHA/BETA COUNTING SYSTEM ALBA (мод. ALBA/LLAB) та програмним забезпеченням ALBA 2000 v.2.5.6. Метою є визначити відповідність даних об’єктів вимогам нормативної документації. Метод спектрометрії базується на фізичній концентрації радіонуклідів з об’єму зразка, вимірюванні швидкості лічби альфа-, бета-випромінювань отриманого сухого залишку зразка, порівняння швидкості рахунку зразка з калібрувальними значеннями активності та розрахунку сумарної альфа-, бета-активності зразка. Основним засобом випробувань є лічильник з низьким фоном ALPHA/BETA COUNTING SYSTEM ALBA 200, нижня межа вимірювань альфа-активності якого 0,02 Бк/л, а бета-активності 0,1Бк/л, відносна випадкова невизначеність результату вимірювань складає 60 % при довірчій ймовірності Р = 0,95. Ефективність реєстрації по альфа-каналу 43 %, фон по альфа-каналу 0,11 імп./хв, за час виміру 60000 с, ефективність реєстрації по бета-каналу 30 %, фон по бета-каналу 1,9 імп./хв, за час виміру 60000 с. Як зразок порівняння для розрахунку сумарної альфа-активності використовується зразок з альфа-випромінюванням 241Am (геометрія 2π), для розрахунку сумарної бета-активності використовується зразок бета-випромінювача сульфату калію з радіонуклідом 40К (геометрія 2π). Маса лічильного зразка в межах від 200 до 1000 мг. Розрахунок значень активності проводиться автоматично, з використанням програмного забезпечення ALBA 2000, v.2.5.6. Вимірювання сумарної активності радіонуклідів в лічильних зразках із використанням методу варто проводити лише в каліброваних геометріях. При цьому обов’язково дотримуються вимог техніки безпеки, кваліфікації персоналу та умов випробувань. Контроль якості вимірювань у альфа-, бета-лічильнику ALBA-2000 v.2.5.6.проводиться якісним і кількісним способами
- …