303 research outputs found

    Physiological responses of cultured bovine granulosa cells to elevated temperatures under low and high oxygen in the presence of different concentrations of melatonin

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    Our understanding of the effects of temperature on granulosa cell (GC) physiology is primarily limited to in vitro studies conducted under atmospheric (approx 20% O2) conditions. In the current series of factorial experiments we identify important effects of O2 level (i.e. 5% vs 20% O2) on GC viability and steroidogenesis, and go onto report effects of standard (37.5°C) vs high (40.0°C) temperatures under more physiologically representative (i.e. 5%) O2 levels in the presence of different levels of melatonin (0, 20, 200 and 2000 pg/mL); a potent free-radical scavenger and abundant molecule within the ovarian follicle. Cells aspirated from antral (4 to 6 mm) follicles were cultured in fibronectin-coated wells using serum-free M199 for up to 144 h. At 37.5 C viable cell number was enhanced and luteinization reduced under 5 vs 20% O2. Oxygen level interacted (P<0.001) with time in culture to affect aromatase activity and cell estradiol (E2) production (pg/mL/105 cells). These decreased between 48 and 96 h for both O2 levels but increased again by 144 h for cells cultured under 5% but not 20% O2. Progesterone (P4) concentration (ng/mL/105 cells) was greater (P<0.001) under 20 vs 5% O2 at 96 and 144 h. Cell number increased (P<0.01) with time in culture under 5% O2 irrespective of temperature. However, higher doses of melatonin increased viable cell number at 40.0°C but reduced viable cell number at 37.5°C (P=0.004). Melatonin also reduced (P<0.001) ROS generation at both O2 levels across all concentrations. E2 increased with time in culture at both temperatures under 5% O2, however P4 declined between 96 to 144 h at 40.0 but not 37.5°C. Furthermore, melatonin interacted (P<0.001) with temperature in a dose dependent manner to increase P4 at 37.5°C but to reduce P4 at 40.0°C. Transcript expression for HSD3B1 paralleled temporal changes in P4 production, and those for HBA were greater at 5% than 20% O2, suggesting that hemoglobin synthesis is responsive to changes in O2 level. In conclusion, 5% O2 enhances GC proliferation and reduces luteinization. Elevated temperatures under 5% O2 reduce GC proliferation and P4 production. Melatonin reduces ROS generation irrespective of O2 level and temperature, but interacts with temperature in a dose dependent manner to influence GC proliferation and luteinization

    Asymmetry Parameter of the K1(1270,1400)K_{1} (1270, 1400) by Analyzing the BK1ννˉB\to K_{1}\nu \bar{\nu} Transition Form Factors within QCD

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    Separating the mixture of the K1(1270) K_{1}(1270) and K1(1400)K_{1}(1400) states, the BK1(1270,1400)ννˉB\to K_{1}(1270, 1400)\nu\bar{\nu} transition form factors are calculated in the three-point QCD sum rules approach. The longitudinal, transverse and total decay widths as well as the asymmetry parameter, characterizing the polarization of the axial K1(1270,1400)K_{1}(1270, 1400) and the branching ratio for these decays are evaluated.Comment: 25 pages, 3 figures, 3 table

    Double-wedged Wollaston-type polarimeter design and integration to RTT150-TFOSC; initial tests, calibration, and characteristics

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    © 2015, Springer Science+Business Media Dordrecht. Photometric and spectroscopic observation capabilities of 1.5-m Russian–Turkish Telescope RTT150 has been broadened with the integration of presented polarimeter. The well-known double-wedged Wollaston-type dual-beam technique was preferred and applied to design and produce it. The designed polarimeter was integrated into the telescope detector TFOSC, and called TFOSC-WP. Its capabilities and limitations were attempted to be determined by a number of observation sets. Non-polarized and strongly polarized stars were observed to determine its limitations as well as its linearity. An instrumental intrinsic polarization was determined for the 1 × 5 arcmin field of view in equatorial coordinate system, the systematic error of polarization degree as 0.2 %, and position angle as 1.9∘. These limitations and capabilities are denoted as good enough to satisfy telescopes’ present and future astrophysical space missions related to GAIA and SRG projects

    The Nose as a Route for Therapy: Part 1. Pharmacotherapy

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    This article reviews nasal structure and function in the light of intranasal pharmacotherapy. The nose provides an accessible, fast route for local treatment of nose and sinus diseases, with lower doses than are necessary systemically and few adverse effects. It can also be used for other medications as it has sufficient surface area protected from local damage by mucociliary clearance, absence of digestive enzymes, responsive blood flow, and provides a rapid route to the central nervous system.Peer reviewe

    Analysis of Various Polarization Asymmetries In The Inclusive bs+b\to s \ell^+ \ell^- Decay In The Fourth-Generation Standard Model

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    In this study a systematical analysis of various polarization asymmetries in inclusive b \rar s \ell^+ \ell^- decay in the standard model (SM) with four generation of quarks is carried out. We found that the various asymmetries are sensitive to the new mixing and quark masses for both of the μ\mu and τ\tau channels. Sizeable deviations from the SM values are obtained. Hence, b \rar s \ell^+ \ell^- decay is a valuable tool for searching physics beyond the SM, especially in the indirect searches for the fourth-generation of quarks (t,b)t', b').Comment: 19 Pages, 10 Figures, 3 Table

    Botanical and Genetic Identification Followed by Investigation of Chemical Composition and Biological Activities on the Scabiosa atropurpurea L. Stem from Tunisian Flora

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    Scarce information about the phenolic composition of Scabiosa atropurpurea L. is available, and no carotenoid compounds have been reported thus far. In this study the phenolic and carotenoid composition of this plant was both investigated and associated bioactivities were evaluated. Aiming to obtain extracts and volatile fractions of known medicinal plants to valorize them in the pharmaceutical or food industries, two techniques of extraction and five solvents were used to determine the biologically active compounds. Gas chromatography coupled to flame ionization and mass spectrometry and liquid chromatography coupled to photodiode array and atmospheric pressure chemical ionization/electrospray ionization mass spectrometry highlighted the presence of 15 volatiles, 19 phenolic, and 24 natural pigments in Scabiosa atropurpurea L. stem samples; among them, the most abundant were 1,8-cineole, chlorogenic acid, cynaroside, and lutein. Bioactivity was assessed by a set of in vitro tests checking for antioxidant, antibacterial, antifungal, and allelopathic (against Brassica oleracea L. and Lens culinaris Medik) effects. Scabiosa atropurpurea L. stem extracts presented a considerable antioxidant, antibacterial, and allelopathic potential, with less antifungal effectiveness. These results indicate that the volatile fractions and extracts from S. atropurpurea L. stem could be considered as a good source of bioactive agents, with possible applications in food-related, agriculture, and pharmaceutical fields. Genetic investigations showed 97% of similarity with Scabiosa tschiliensis, also called Japanese Scabiosa

    МЕХАНИЗМЫ ОЧАГОВ ЗЕМЛЕТРЯСЕНИЙ И ПОЛЕ НАПРЯЖЕНИЙ МОНГОЛИИ И ПРИЛЕГАЮЩИХ ТЕРРИТОРИЙ

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    We have compiled and analyzed earthquake focal solutions for the territory of Mongolia and its surroundings in order to reveal a spatial variability of stress orientation and stress regimes of the crust. According to the stress inversion results, the SHmax is turning from W-E in the eastern Mongolia to SW-NE in the Gobi Altay and the central Mongolia, and then to S-N in the western part of the region. Comparison with data derived from GPS measurements shows that directions of the strain axes revealed by the geodetic and seismological observations are generally consistent. A contradiction is found for the Bolnai zone where results of GPS estimation indicate the predominance of extension (in the SE-NW direction), whereas earthquake data for the longer period of seismic observations reveal compression. Compression in this zone is mainly due to the Tsetserleg-Bolnai earthquakes contribution; however, a part of the recent data on focal mechanisms fits an extensional stress field with the NNW orientated extension axis. These data are in accordance with some published works which suggest a transtensive field from some structural geology studies in the eastern part of the Bolnai zone.The paper is supplemented with a list of M≥4.5 earthquake fault plane solutions and unpublished focal mechanisms for some M≤4.5 earthquakes of the northern Mongolia and the southern Baikal region.Введение. Механизмы очагов землетрясений наряду с геодезическими и другими данными служат источником информации о напряженно-деформированном состоянии земной коры. Задачи оценки тектонического режима и скорости деформирования особенно актуальны для внутриплитных областей, характеризующихся высоким уровнем сейсмичности. Одной из таких областей является Монголия, на территории которой известны землетрясения с М=8.0 (рис. 1). В представляемой работе собраны и проанализированы механизмы очагов землетрясений с M≥4.5 с целью проследить пространственную изменчивость поля напряжений земной коры. Данные. Опубликованные данные о фокальных решениях можно разделить на две группы в зависимости от применяемых для их определения методов. К первой группе относятся механизмы, полученные моделированием волновых форм на удаленных и региональных станциях. Вторая группа решений получена при использовании метода полярности первых вступлений волн. Данный метод широко применялся для умеренной силы землетрясений северной части Монголии и Южной Сибири, что обусловлено более плотным покрытием этого региона сейсмостанциями. Используемые для анализа в данной работе решения представлены в таблице (в разделе «Дополнительные материалы») и на карте (рис. 2). Методы. Для инверсии поля напряжений использовались два подхода. Для землетрясений основных сейсмических зон (Болнай, Гобийский Алтай, Могод и т.д.) применялась программа Win-Tensor [Delvaux, Sperner, 2003], в которой реализован метод right dihedra [Angelier, 1984]. Для получения более сглаженной по всей территории картины ориентации осей напряжений использовалась программа SATSI [Hardebeck, Michael, 2006], минимизирующая разницу между соседними «индивидуальными» стресс-тензорами для сейсмоактивных областей. Для более корректного сравнения сейсмологических данных с результатами GPS-измерений и визуализации сейсмотектонических деформаций представлены стереограммы средних фокальных механизмов [Nikitin, Yunga, 1977; Yunga, 1990]. Результаты. Полученные результаты показывают, что фокальные решения землетрясений южной, западной и восточной части Монголии однородны и представлены главным образом сдвиговыми и взбросовыми подвижками в очагах. Большим разнообразием кинематических типов разрывов характеризуется территория к северу от Болнайского разлома. Для непосредственно Болнайской зоны не удалось получить единого стресс-тензора. Выборка разделилась на главные толчки (Болнайское и Цэцэрлэгское землетрясения 1905 г.), состоящие из субисточников, и события, зарегистрированные в период инструментальных наблюдений. Последние показывают наличие в выборке решений, удовлетворяющих режиму растяжения. В целом, наблюдается изменение ориентации оси SHmax от направления Ю-С в западной части Монголии до ЮЗ-СВ в Гобийском Алтае и в центральной части страны и до широтного направления в Восточной Монголии. Обсуждение результатов. Очевидно, что основные характеристики поля напряжений на представленной территории уже выявлены и описаны в предшествующих работах [Zhalkovskii et al., 1995; Petit et al., 1996; Delvaux et al., 1998; Melnikova et al., 2004; Melnikova, Radziminovich, 2005; San’kov et al., 2005; Gol’din, Kuchai, 2007; Radziminovich et al., 2007; Parfeevets, San’kov, 2010; San’kov et al., 2011; Parfeevets, San’kov, 2012; Rebetsky et al., 2013; Tataurova et al., 2014; Kuchai, Kozina, 2015; Karagianni et al., 2015; и др.]. Все увеличивающийся объем новых данных, с одной стороны, подтверждает сделанные ранее выводы, а с другой – позволяет выявить некоторые детали. Результаты, полученные по сейсмологическим данным, согласуются с данными, полученными в ходе геолого-структурных работ [Parfeevets, Sankov, 2012] и GPS-измерений [Calais et al., 2003; Loukhnev et al., 2010]. Выделяется Болнайская зона, которая по геодезическим расчетам характеризуется деформацией удлинения земной коры или растяжением. Выше отмечалось, что часть фокальных механизмов соответствует такому полю напряжений. Более того, замеры трещиноватости также приводят авторов [Parfeevets, Sankov, 2012] к выводу о режиме транстенсии в восточной части Болнайской зоны, связанном, вероятно, с дивергенцией Евразийской и Амурской плит [Petit, Fournier, 2005]. Характер изменений сейсмотектонических деформаций в этом районе позволил авторам работы [Kuchai, Kozina, 2015] выделить, хоть и в широких пределах, границу Амурской плиты. По данным о землетрясениях с M≥7.0 была рассчитана скорость деформации по формуле Кострова (табл. 2). Для временного интервала в 100 лет она составила 1.12×1020 N m yr–1, что является высоким значением для внутриконтинентальных областей по сравнению с модельными значениями [Holt et al., 1995, 2000]. Очевидно, это связано с сильнейшими землетрясениями региона, произошедшими на протяжении небольшого интервала времени. Заключение. Карта фокальных механизмов и результаты инверсии поля тектонических напряжений могут быть полезны при сейсмотектоническом и геодинамическом анализе Центральной Азии. В разделе «Дополнительные материалы» приведена компиляционная таблица механизмов очагов землетрясений с M≥4.5 и ранее неопубликованные механизмы очагов землетрясений Северной Монголии и Южного Прибайкалья с M≤4.5

    Collaborative prognostics in Social Asset Networks

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    With the spread of Internet of Things (IoT) technologies, assets have acquired communication, processing and sensing capabilities. In response, the fi eld of Asset Management has moved from fleet-wide failure models to individualised asset prognostics. Individualised models are seldom truly distributed, and often fail to capitalise the processing power of the asset fleet. This leads to hardly scalable machine learning centralised models that often must nd a compromise between accuracy and computational power. In order to overcome this, we present a novel theoretical approach to collaborative prognostics within the Social Internet of Things. We introduce the concept of Social Asset Networks, de ned as networks of cooperating assets with sensing, communicating and computing capabilities. In the proposed approach, the information obtained from the medium by means of sensors is synthesised into a Health Indicator, which determines the state of the asset. The Health Indicator of each asset evolves according to an equation determined by a triplet of parameters. Assets are given the form of the equation but they ignore their parametric values. To obtain these values, assets use the equation in order to perform a non-linear least squares t of their Health Indicator data. Using these estimated parameters, they are interconnected to a subset of collaborating assets by means of a similarity metric. We show how by simply interchanging their estimates, networked assets are able to precisely determine their Health Indicator dynamics and reduce maintenance costs. This is done in real time, with no centralised library, and without the need for extensive historical data. We compare Social Asset Networks with the typical self-learning and fleet-wide approaches, and show that Social Asset Networks have a faster convergence and lower cost. This study serves as a conceptual proof for the potential of collaborative prognostics for solving maintenance problems, and can be used to justify the implementation of such a system in a real industrial fleet.EU H202
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