22 research outputs found

    Внутриландшафтное распределение снегозапасов в бассейне р. Майма (низкогорья Русского Алтая)

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    The paper presents the results of observations and cartographic modeling of distribution of maximum snow storages (snowpack water equivalent) in the low-mountain forest landscapes of the Maima river basin in different by snow amount winters. The weather conditions during cold periods of 2014/15-2017/18 were analyzed. The data on precipitation and mean monthly temperatures for the above mentioned seasons were compared with averaged values for 1998-2018 as the whole. It was found that the values of snow storages as well as losses for evaporation here are mainly conditioned by the meteorological parameters of the cold period. The algorithm of mapping with the use of the landscape cartographic basis and corrections for features of the relief and the character of the underlying surface is proposed. This algorithm may be used in the studies of snow accumulation in low-mountain forest landscapes. It had been found that the cold periods of 2014/15 and 2016/17 were characterized by the highest excess of winter precipitation over the averaged long-term values, whereas the lowest values were typical for 2017/18 and 2015/16. According to mean monthly air temperatures, the investigated winters were warm. The data on the in situ measurements and calculations confirm the dependence of snow accumulation in the basin on an altitude gradient, vegetation features, expositions and surface steepness. Consistently high values of snow storages are characteristic for the black-taiga landscapes on the shadow slopes (North-Western, Northern and North-Eastern expositions) with an angle of up to 20° with small-leaved forests. Minimum values of snow storages are observed in the sub-taiga part of the basin on the slopes of light (South-Western, Southern and South-Eastern) and transitional (Western and Eastern) expositions with an angle of more than 20° with the domination of original coniferous forests.Изложены результаты (2014/15-2017/18 гг.) снегомерных работ и картографического моделирования максимальных снегозапасов в преимущественно низкогорном бассейне р. Майма. Установлено, что максимальные снегозапасы наблюдаются на теневых склонах с углом наклона до 20о с мелколиственными лесами; минимальные - на склонах световых и переходных экспозиций с углом наклона более 20о с коренными хвойными лесами

    Low temperature microhardness of Xe-intercalated fullerite C₆₀

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    The Vickers microhardness of Xe-intercalated polycrystalline fullerite C₆₀ (XexC₆₀, x ≃ 0.35) is measured in a moderately low temperature range of 77 to 300 K. A high increase in the microhardness of the material (by a factor of 2 to 3) as compared to that of pure C₆₀ single crystals is observed. It is shown that the step-like anomaly in the temperature dependences of the microhardness of pure C₆₀ single crystals recorded under the orientational fcc-sc phase transition (Tc ≃ 260 K) is also qualitatively retained for XexC₆₀, but its onset is shifted by 40 K towards lower temperatures and the step becomes less distinct and more smeared. This behavior of ̅NV(T) correlates with x-ray diffraction data, the analysis of which revealed a considerable influence of xenon interstitial atoms on the peculiar features of fullerite thermal expansion due to orientational phase transitions (see the paper by A.I. Prokhvatilov et al. in this issue)

    ОСОБЕННОСТИ ПРОСТРАНСТВЕННОЙ ДИФФЕРЕНЦИАЦИИ СНЕЖНОГО ПОКРОВА В НИЗКОГОРНЫХ ЛАНДШАФТАХ РУССКОГО АЛТАЯ (НА ПРИМЕРЕ БАССЕЙНА Р. МАЙМА)

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    The paper presents results of snow route measurements carried out during two winter seasons (2014/15 and 2015/16) over the period of maximum snow accumulation. The region of investigation was mainly the lowmountain basin of the river Maima (North, North-East Altai). Meteorological conditions for these periods (amounts of precipitation and mean monthly temperatures) were compared with climatic data (1985– 2016). The results obtained allowed establishing a relationship between the spatial and temporal variability of the snow depth, density and SWE (snow-water equivalent) and the weather conditions, orographic features (exposure and steepness of slopes), and characteristics of the underlying surface. The winter of 2014/15 was warm and moderately snowy season, while the winter of 2015/16 was warm but with small amount of snow. At the subtype level of the landscapes the maximum values of the snow cover thickness and the snow storage were observed in the chern-taiga landscapes, and the smallest ones – in the sub-taiga part of the basin area. The maximum snow storages (SWE) are characteristic for the secondary small-leaved forests and meadows, where these values exceed similar ones under the indigenous fir trees by 30%.The paper presents results of snow route measurements carried out during two winter seasons (2014/15 and 2015/16) over the period of maximum snow accumulation. The region of investigation was mainly the lowmountain basin of the river Maima (North, North-East Altai). Meteorological conditions for these periods (amounts of precipitation and mean monthly temperatures) were compared with climatic data (1985– 2016). The results obtained allowed establishing a relationship between the spatial and temporal variability of the snow depth, density and SWE (snow-water equivalent) and the weather conditions, orographic features (exposure and steepness of slopes), and characteristics of the underlying surface. The winter of 2014/15 was warm and moderately snowy season, while the winter of 2015/16 was warm but with small amount of snow. At the subtype level of the landscapes the maximum values of the snow cover thickness and the snow storage were observed in the chern-taiga landscapes, and the smallest ones – in the sub-taiga part of the basin area. The maximum snow storages (SWE) are characteristic for the secondary small-leaved forests and meadows, where these values exceed similar ones under the indigenous fir trees by 30%

    Оценка параметров снежного покрова по данным наблюдений на метеостанциях в небольших речных бассейнах на юге Западной Сибири

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    In this study, we analyzed the accuracy of snow observations at weather stations compared to the data of snow measurements in the vicinity of these stations. Also, the variations of measurement errors were estimated considering the inter-annual snowpack variability and landscape heterogeneity of the river basins. The studies were conducted in three catchments in the south of Western Siberia: forest-steppe the Kasmala River (2011–2020), low mountain the Mayma River (2015–2020), and steppe the Kuchuk River (2019–2020). The results showed that the accuracy of snow measurements at the weather stations was higher in the low mountain catchment than in the plain basins. Interannual differences in precipitation combined with wind transport influenced the most significant errors in the Kasmala catchment (relative error of snow depth on the snow gauge – 46,3%, and SWE on the permanent course – 17,3%). However, in the Mayma catchment, the snow depth measurements on the snow gauge agreed well with the catchment means in all years (mean relative error 7,7%). The relative error of snow depth measurements on the snow gauge in the Kuchuk catchment was 7,5%, and of SWE on the permanent snow course was 19,1%. The small snow depth error occurred due to the composition of the error distribution and large differences between open and forested areas.Сравниваются материалы наблюдений за снежным покровом на метеостанциях и снегомерные наблюдения в водосборных бассейнах, где расположены эти станции. Исследования вели в трёх бассейнах на юге Западной Сибири: в лесостепном бассейне р. Касмала (2011–2020 гг.), низкогорном бассейне р. Майма (2015–2020 гг.) и степном бассейне р. Кучук (2019–2020 гг.). Сравнение проводилось на трёх пространственно-временных уровнях изменчивости: межгодовом (влияние межгодовой изменчивости осадков); внутрибассейновом (влияние рельефа и растительности); внутригодовом (влияние метеорологических условий конкретного зимнего периода)

    Пространственная и временная изменчивость снежного покрова в южной лесостепи Верхней Оби

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    The study area is the forest-steppe in the Upper Ob basin located on the south of the West Siberian Plain. The results of studies of the dates of setting-up and loss of a stable snow cover and its duration are presented, the thickness of snow and snow storages for the period of maximum snow accumulation are analyzed. We used observational data obtained on routes and meteorological sites in 1966–2018 together with our own snow measurements of 2011–2019. It was found that in the southern forest-steppe, the duration of the stable snow cover presence decreases mainly as a result of its earlier destruction. At the same time, on the routes in a «field» the thickness of snow and snow storage increase due to growth of winter precipitation. But no such trend is observed on the routes in a «forest» which is explained by influence of its canopy density. The snow cover here is unevenly distributed over the territory because the driſted snow transport depends mainly on features of the vegetation cover and the terrain relief. The route snow surveys performed near weather stations do not reflect the entire landscape diversity of the territory.Проанализированы особенности сезонного снегонакопления за многолетний период. Установлены тенденции изменений характеристик снежного покрова с середины 1960-х годов и его пространственное распределение в зависимости от ландшафтов в пределах южной лесостепи Верхней Оби. Использованы данные государственных гидрометеостанций и собственных снегомерных работ 2011–2019 гг

    Safety and immunogenicity of rAd26 and rAd5 vector-based heterologous prime-boost COVID-19 vaccine against SARS-CoV-2 in healthy adolescents: an open-label, non-randomized, multicenter, phase 1/2, dose-escalation study

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    To protect young individuals against SARS-CoV-2 infection, we conducted an open-label, prospective, non-randomised dose-escalation Phase 1/2 clinical trial to evaluate the immunogenicity and safety of the prime-boost “Sputnik V” vaccine administered at 1/10 and 1/5 doses to adolescents aged 12–17 years. The study began with the vaccination of the older cohort (15-to-17-year-old participants) with the lower (1/10) dose of vaccine and then expanded to the whole group (12-to-17-year-old participants). Next, 1/5 dose was used according to the same scheme. Both doses were well tolerated by all age groups. No serious or severe adverse events were detected. Most of the solicited adverse reactions were mild. No significant differences in total frequencies of adverse events were registered between low and high doses in age-pooled groups (69.6% versus 66.7%). In contrast, the 1/5 dose induced significantly higher humoral and T cell-mediated immune responses than the 1/10 dose. The 1/5 vaccine dose elicited higher antigen-binding (both S and RBD-specific) as well as virus-neutralising antibody titres at the maximum of response (day 42), also resulting in a statistically significant difference at a distanced timepoint (day 180) compared to the 1/10 vaccine dose. Higher dose resulted in increased cross-neutralization of Delta and Omicron variants.;Clinical Trial RegistrationClinicalTrials.gov, NCT04954092, LP-007632

    Intra-landscape distribution of snow storage in the Mayma river basin (low-mountain area of the Russian Altai)

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    The paper presents the results of observations and cartographic modeling of distribution of maximum snow storages (snowpack water equivalent) in the low-mountain forest landscapes of the Maima river basin in different by snow amount winters. The weather conditions during cold periods of 2014/15-2017/18 were analyzed. The data on precipitation and mean monthly temperatures for the above mentioned seasons were compared with averaged values for 1998-2018 as the whole. It was found that the values of snow storages as well as losses for evaporation here are mainly conditioned by the meteorological parameters of the cold period. The algorithm of mapping with the use of the landscape cartographic basis and corrections for features of the relief and the character of the underlying surface is proposed. This algorithm may be used in the studies of snow accumulation in low-mountain forest landscapes. It had been found that the cold periods of 2014/15 and 2016/17 were characterized by the highest excess of winter precipitation over the averaged long-term values, whereas the lowest values were typical for 2017/18 and 2015/16. According to mean monthly air temperatures, the investigated winters were warm. The data on the in situ measurements and calculations confirm the dependence of snow accumulation in the basin on an altitude gradient, vegetation features, expositions and surface steepness. Consistently high values of snow storages are characteristic for the black-taiga landscapes on the shadow slopes (North-Western, Northern and North-Eastern expositions) with an angle of up to 20° with small-leaved forests. Minimum values of snow storages are observed in the sub-taiga part of the basin on the slopes of light (South-Western, Southern and South-Eastern) and transitional (Western and Eastern) expositions with an angle of more than 20° with the domination of original coniferous forests

    FEATURES OF SPATIAL DIFFERENTIATION OF SNOW COVER IN LOW-MOUNTAIN LANDSCAPES OF THE RUSSIAN ALTAI (CASE STUDY OF THE MAIMA RIVER BASIN)

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    The paper presents results of snow route measurements carried out during two winter seasons (2014/15 and 2015/16) over the period of maximum snow accumulation. The region of investigation was mainly the lowmountain basin of the river Maima (North, North-East Altai). Meteorological conditions for these periods (amounts of precipitation and mean monthly temperatures) were compared with climatic data (1985– 2016). The results obtained allowed establishing a relationship between the spatial and temporal variability of the snow depth, density and SWE (snow-water equivalent) and the weather conditions, orographic features (exposure and steepness of slopes), and characteristics of the underlying surface. The winter of 2014/15 was warm and moderately snowy season, while the winter of 2015/16 was warm but with small amount of snow. At the subtype level of the landscapes the maximum values of the snow cover thickness and the snow storage were observed in the chern-taiga landscapes, and the smallest ones – in the sub-taiga part of the basin area. The maximum snow storages (SWE) are characteristic for the secondary small-leaved forests and meadows, where these values exceed similar ones under the indigenous fir trees by 30%

    Single-cell transcriptome analysis of endometrial tissue

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    STUDY QUESTION: How can we study the full transcriptome of endometrial stromal and epithelial cells at the single-cell level? SUMMARY ANSWER: By compiling and developing novel analytical tools for biopsy, tissue cryopreservation and disaggregation, single-cell sorting, library preparation, RNA sequencing (RNA-seq) and statistical data analysis. WHAT IS KNOWN ALREADY: Although single-cell transcriptome analyses from various biopsied tissues have been published recently, corresponding protocols for human endometrium have not been described. STUDY DESIGN, SIZE, DURATION: The frozen-thawed endometrial biopsies were fluorescence-activated cell sorted (FACS) to distinguish CD13-positive stromal and CD9-positive epithelial cells and single-cell transcriptome analysis performed from biopsied tissues without culturing the cells. We studied gene transcription, applying a modern and efficient RNA-seq protocol. In parallel, endometrial stromal cells were cultured and global expression profiles were compared with uncultured cells. PARTICIPANTS/MATERIALS, SETTING, METHODS: For method validation, we used two endometrial biopsies, one from mid-secretory phase (Day 21, LH+8) and another from late-secretory phase (Day 25). The samples underwent single-cell FACS sorting, single-cell RNA-seq library preparation and Illumina sequencing. MAIN RESULTS AND THE ROLE OF CHANCE: Here we present a complete pipeline for single-cell gene-expression studies, from clinical sampling to statistical data analysis. Tissue manipulation, starting from disaggregation and cell-type-specific labelling and ending with single-cell automated sorting, is managed within 90 min at low temperature to minimize changes in the gene expression profile. The single living stromal and epithelial cells were sorted using CD13- and CD9-specific antibodies, respectively. Of the 8622 detected genes, 2661 were more active in cultured stromal cells than in biopsy cells. In the comparison of biopsy versus cultured cells, 5603 commonly expressed genes were detected, with 241 significantly differentially expressed genes. Of these, 231 genes were up- and 10 down-regulated in cultured cells, respectively. In addition, we performed a gene ontology analysis of the differentially expressed genes and found that these genes are mainly related to cell cycle, translational processes and metabolism. LIMITATIONS, REASONS FOR CAUTION: Although CD9-positive single epithelial cells sorting was successfully established in our laboratory, the amount of transcriptome data per individual epithelial cell was low, complicating further analysis. This step most likely failed due to the high dose of RNases that are released by the cells' natural processes, or due to rapid turnaround time or the apoptotic conditions in freezing- or single-cell solutions. Since only the cells from the late-secretory phase were subject to more focused analysis, further studies including larger sample size from the different time-points of the natural menstrual cycle are needed. The methodology also needs further optimization to examine different cell types at high quality. WIDER IMPLICATIONS OF THE FINDINGS: The symbiosis between clinical biopsy and the sophisticated laboratory and bioinformatic protocols described here brings together clinical diagnostic needs and modern laboratory and bioinformatic solutions, enabling us to implement a precise analytical toolbox for studying the endometrial tissue even at the single-cell level.Peer reviewe
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