Wind-driven summer surface hydrography of the eastern Siberian shelf

High interannual variability of summer surface salinity over the Laptev and East Siberian Sea shelves derived from historical records of the 1950s–2000s is attributed to atmospheric vorticity variations. In the cyclonic regime (positive vorticity) the eastward diversion of the Laptev Sea riverine water results in a negative salinity anomaly to the east of the Lena Delta and farther to the East Siberian Sea, and a positive anomaly to the north of the Lena Delta. Anticyclonic (negative) vorticity results in negative salinity anomalies northward from the Lena Delta due to freshwater advection toward the north, and a corresponding salinity increase eastward

HISTÓRIA DOS ESTUDOS MUSICOLÓGICOS NAS UNIVERSIDADES DE CRACÓVIA E LVIV

This work deals with the system research of the activities of the departments of musicology of the Jagiellonian and Lviv Universities in the context of the Jagiellonian tradition of Poland and Ukraine in the original refraction of principles of the European musical academic education since the time of their foundation in years 1911-1912 and till the beginning of the XXI century. Besides the educational orientation of the Jagiellonian tradition have been revealed. This tradition inextricably linked with the national-confessional polysyllabity within the teacher's and student's community. It has been established that the Neojagiellonian-Panslavic worldview of the XIX – first half of the XX century was historically significant corrective component of the existence of Krakow and Lviv Universities. "Equation on the European East" of the most prominent representatives of Polish culture and art in the twentieth century was a testimony of the influence of that worldview.Este trabalho trata da pesquisa do sistema das atividades dos departamentos de musicologia das Universidades Jagiellonian e Lviv no contexto da tradição Jagiellonian da Polônia e Ucrânia na refração original dos princípios da educação acadêmica musical europeia desde a época de sua fundação nos anos 1911-1912 e até o início do século XXI. Além disso, a orientação educacional da tradição jagielloniana foi revelada. Esta tradição está inextricavelmente ligada à polissilabidade nacional-confessional dentro da comunidade de professores e alunos. Foi estabelecido que a visão de mundo Neojagiellonian-Panslavic do século XIX – primeira metade do século XX foi um componente corretivo historicamente significativo da existência das universidades de Cracóvia e Lviv. A "Equação sobre o Leste Europeu" dos representantes mais proeminentes da cultura e arte polonesa no século XX foi um testemunho da influência dessa visão de mundo

Cytotoxicity Evaluation of Ammonia-Modified Graphene Oxide Particles in Lung Cancer Cells and Embryonic Stem Cells

Potential toxicity of graphene oxide (GO) is a subject of increasing research interest in the recent years. Here, we have evaluated the cytotoxicity of ammonia-modified GO (GO-NH2) and pristine GO particles in human lung cancer cells, A549 and embryonic stem cells, Lep3 exposed to different particles concentrations (0.1, 1, 10, 20, and 50 μg/ml) for different times (24 and 48h). Compared with GO, GO-NH2 particles possessed smaller size, positive surface charge and higher thickness. An increased propensity to aggregation in cell cultures was also found for GO-NH2 particles. Cytotoxicity evaluation revealed that GO-NH2 particles are more toxic than pristine GO. Applied at concentrations of 10, 20 and 50 μg/ml for 24h they affect significantly cell morphology of viable embryonic stem cells whereas human lung cancer A549 cells seem to be relatively more resistant to short-time exposure. After 48h exposure however cell proliferation of A549 cells was strongly suppressed in a dose-dependent manner while the proliferation ability of embryonic stem cells was not affected. These results suggested that both GO particles exert different degree of cytotoxicity which is time, dose and cell dependent. In general, ammonia-modified GO particles are more toxic than the pristine GO which should be taken into account for future biomedical applications

Diurnal distribution of carbohydrates and fat affects substrate oxidation and adipokine secretion in humans.

BACKGROUND: A diet in which fat is mainly eaten in the morning and carbohydrates mainly in the evening (compared with the reverse order) was recently shown to worsen glycemic control in people with prediabetes. OBJECTIVE: We investigated the effects of these dietary patterns on energy metabolism, and on the daily profiles of circulating lipids, adipokines, and inflammatory markers. DESIGN: In a randomized controlled crossover trial, 29 nonobese men (with normal glucose tolerance, n = 18; or impaired fasting glucose/glucose tolerance, n = 11) underwent 2 isocaloric 4-wk diets: 1) carbohydrate-rich meals until 1330 and fat-rich meals between 1630 and 2200 (HC/HF); or 2) the inverse sequence of meals (HF/HC). During a 12-h clinical investigation day after each intervention period, 2 meal tolerance tests were performed, at 0900 and 1540, respectively. Substrate oxidation and concentrations of circulating lipids, adipokines, and cytokines were assessed pre- and postprandially. The postprandial inflammatory response in leukocytes was analyzed ex vivo. RESULTS: Fasting carbohydrate oxidation decreased (P = 0.004) and lipid oxidation increased (P = 0.012) after the HC/HF diet. Fasting concentrations of blood markers did not differ between diets. The diets modulated the daily profiles of carbohydrate oxidation, lipid oxidation, and β-hydroxybutyrate, although the average daily values of these parameters showed no difference between the diets, and no interaction between diet and glucose tolerance status. Diurnal patterns of triglycerides, low-density lipoprotein cholesterol, leptin, visfatin, and of LPS-induced cytokine secretion in blood leukocytes were also modulated by the diets. Average daily concentrations of leptin (P = 0.017) and visfatin (P = 0.041) were lower on the HF/HC diet than on the HC/HF diet. CONCLUSIONS: Diurnal distribution of carbohydrates and fat affects the daily profiles of substrate oxidation, circulating lipids, and cytokine secretion, and alters the average daily concentrations of adipokine secretion in nonobese nondiabetic humans. The study was registered at clinicaltrials.gov as NCT02487576

Моделирование и практическая реализация широкополосной двухгребневой рупорной антенны с шириной рабочей полосы более октавы и высоким уровнем кроссполяризационной развязки

Introduction. The resolution of the problem of radio polarimetry in multiposition microwave screening systems (MMSS) with aperture synthesis requires the use of antennas with a high level of cross-polarization discrimination (XPD) in a wide spatial angle. The radio images are reconstructed in MMSS at distances commensurate with the aperture of the antenna structures. Therefore, the value of the spatial angle, at which high XPD is required, can reach 30°. This leads to a new problem of creating an antenna configuration of the X and Ku band, the application of which in MMSS will resolve the problem of constructing a radio image of depolarized microwave radiation scattered on the human body in the form of hidden dangerous objects.Aim. To develop a double-ridged receiving antenna for long-term operation in MMSS with an XPD level of 28 dB at a spatial angle of 30° and operating frequencies of 8…20 GHz.Materials and methods. The requirements for the receiving antenna in MMSS were determined. Theoretical justifications were proposed for the choice of antenna design. Aperture synthesis was used to construct microwave images in MMSS. The stages and results of modelling broadband double-ridge antennas were presented using the CST Studio software broadly applied for three-dimensional electro-magnetic field modelling. The results of modelling pyramidal and conical double-ridged antennas, as well as those in circular and elliptical waveguides, were analyzed. The designed antenna was tested in an anechoic chamber. The measurement results were compared with those obtained during simulation.Results. An elliptical double-ridged horn antenna with a VSWR of no more than 2 and cross-polarization discrimination in a spatial angle of 30° of no less than 28 dB for the frequency range that covers an octave was designed and constructed.Conclusion. The developed antenna can be used in MMSS for the purpose of detecting the effect of micro-wave radiation depolarization as hidden dangerous objects on a human body. Such characteristics of the antenna as its high XPD value in a wide spatial angle will allow the future introduction of microwave polarimetry in MMSS.Введение. Для решения задачи радиополяриметрии в многопозиционных микроволновых досмотровых системах (ММДС) с апертурным синтезом необходимо использовать антенны с высоким уровнем кроссполяризационной развязки (КПР) в широком пространственном угле. Восстановление радиоизображений в ММДС происходит на дистанциях, соизмеримых с размерами апертуры антенных структур, поэтому значение пространственного угла, в котором необходимо выполнение требования высокой КПР, может достигать 30°. Таким образом, возникает новая задача создания антенной структуры X- и Ku-диапазонов, применение которой в ММДС позволило бы решить задачу построения радиоизображения деполяризованного микроволнового излучения, рассеянного скрытыми опасными объектами на теле человека.Цель работы. Разработка приемной антенны жесткой конструкции для долговременной эксплуатации в ММДС с уровнем КПР 28 дБ при пространственном угле 30° и рабочих частотах 8… 20 ГГц.Материалы и методы. Определены требования для приемной антенны в ММДС. Приведены теоретические обоснования для выбора конструкции антенны. В разработанной ММДС для построения микроволнового изображения используется апертурный синтез. Представлены этапы и результаты моделирования широкополосных двухгребневых антенн в программе трехмерного моделирования электромагнитного поля CST Studio. Рассмотрены результаты моделирования двухгребневых антенн: пирамидальной, конической, в круглом и эллиптическом волноводах. Произведено сравнение результатов измерения в безэховой камере для макета полученной антенны и результатов моделирования.Результаты. Разработана и изготовлена двухгребневая эллиптическая антенна жесткой конструкции, с КСВН не более 2 и кроссполяризационной развязкой в пространственном угле 30° не менее 28 дБ в диапазоне частот, перекрывающем октаву.Заключение. Антенна может быть использована в ММДС для детектирования эффекта деполяризации микроволнового излучения скрытыми опасными объектами на теле человека. Высокое значение КПР антенны в широком пространственном угле позволит в дальнейшем внедрить микроволновую поляриметрию в ММДС

The effect of radiation losses in localized fluorescence upon laser pumping of fluorescent random media

Background and Objectives: Excitation of fluorescence upon laser pumping of fluorescent multiple scattering media is a complex process that plays a key role in many applications of modern optics and laser physics, from optical biomedical diagnostics to controlling the parameters of functional materials for photonics and optoelectronics. The effect of radiation losses in local fluorescence emitters, which are associated with laser speckles in pumped random media, on the fluorescence output is considered. Materials and Methods: Within the framework of the concept of an ensemble of statistically independent local fluorescence emitters in a laser-pumped random medium, a model of radiation losses in an arbitrarily chosen local emitter is considered. The model takes into account both an extreme value of the cross section of radiation losses for a single emitter, which depends on its characteristic size and the concentration of fluorophore molecules in the medium, and the effect of radiation exchange with other emitters. The scattering properties of a laser-pumped fluorescent medium are considered as a suppressing factor for the ballistic radiation transfer between the local emitters. The modeled results are compared to the previously obtained empirical data on the effective cross section of radiation losses for Rhodamine-6G-saturated layers of close-packed anatase nanoparticles under pulsed laser pumping at the wavelength of 532 nm. Results: The relationship between the effective cross section of radiation losses and the characteristic size of the emitters, the concentration of fluorophore molecules, and the mean scattering free path of fluorescent radiation was obtained. It was found within the framework of the considered model that both the characteristic size of local emitters and the reduction factor to the cross section of radiation losses due to light transfer from other emitters are practically independent of the pump intensity, with the exception of a narrow interval of low intensities. On the other hand, the scattering length significantly affects these characteristics due to the “screening” effect in the case of expressed multiple scattering. Conclusion: Radiation exchange between local stochastic emitters of fluorescence radiation in laser-pumped random media is one of the key factors controlling the fluorescence response of the medium with increasing pump intensity. The considered phenomenological model makes it possible to adequately interpret the experimentally observed features of the behavior of the effective cross section of radiation losses for these systems. The obtained results can be used as a physical basis for the development of new approaches to laser probing of random media in terms of the interpretation of the experimental data

The rs738409 (I148M) Variant of the PNPLA3 Gene and Type 2 Diabetes in Yakutia

The purpose of our research was to study the association of the PNPLA3 SNP rs738409 (C>G) with type 2 diabetes (T2D) in the Yakuts. The frequency distribution of alleles and genotypes of the PNPLA3 rs738409 SNP was in accordance with HWE. There were no statistically significant differences in the distribution of alleles and genotypes of the PNPLA3 SNP rs738409 (C>G) between T2D patients and non-T2D patients (P>0.05); the G allele and homozygous GG genotype prevailed in both groups. In T2D patients, a high frequency of the G allele (74.1%) was found, with a predominance of the GG genotype (58.5%). We also found that the mutant allele frequency is higher than in the studied populations of the world. Further studies with larger sample size are required to achieve sufficient statistical power to detect the association of the PNPLA3 SNP (rs738409 with the development of T2D in Yakut patients

Biochemical Discrimination between Selenium and Sulfur 1: A Single Residue Provides Selenium Specificity to Human Selenocysteine Lyase

Selenium and sulfur are two closely related basic elements utilized in nature for a vast array of biochemical reactions. While toxic at higher concentrations, selenium is an essential trace element incorporated into selenoproteins as selenocysteine (Sec), the selenium analogue of cysteine (Cys). Sec lyases (SCLs) and Cys desulfurases (CDs) catalyze the removal of selenium or sulfur from Sec or Cys and generally act on both substrates. In contrast, human SCL (hSCL) is specific for Sec although the only difference between Sec and Cys is the identity of a single atom. The chemical basis of this selenium-over-sulfur discrimination is not understood. Here we describe the X-ray crystal structure of hSCL and identify Asp146 as the key residue that provides the Sec specificity. A D146K variant resulted in loss of Sec specificity and appearance of CD activity. A dynamic active site segment also provides the structural prerequisites for direct product delivery of selenide produced by Sec cleavage, thus avoiding release of reactive selenide species into the cell. We thus here define a molecular determinant for enzymatic specificity discrimination between a single selenium versus sulfur atom, elements with very similar chemical properties. Our findings thus provide molecular insights into a key level of control in human selenium and selenoprotein turnover and metabolism