CHANGES OF RADIAL GROWTH IN PINE STAND DAMAGED BY FIRE IN WEST POLISSYA

Дендрохронологічними методами оцінено наслідки низової пожежі 2012 р. у 50-річному чистому сосновому насадженні в Поліссі. Виявлено, що після пошкодження пожежею деревостану поряд з погіршенням стану дерев спостерігалася депресія радіального приросту сосни, яка посилювалася посухами. На основі середнього квадратичного відхилення від багаторічного ходу температури та опадів (за період з 1945 по 2015 рр.) розраховано критерії, за якими визначають аномальність погодних умов. Встановлено особливості формування шарів деревини у пошкодженому пожежею сосняку, зокрема залежно від категорій санітарного стану та класів Крафта. Зменшення радіального приросту посилювалося із погіршенням стану дерев. Порівняно з допожежним періодом відбулося зменшення шарів річної деревини: в ослаблених – на 44, дуже ослаблених – на 49 та у відмираючих – на 75 %. Приріст до 2016 р. не відновився до передпожежного рівня і зберіг чітку ієрархічну тенденцію: найбільший радіальний приріст – у панівних дерев і відповідно менший – у співпанівних дерев. У пошкодженому насадженні після пожежі спостерігалося зменшення величин шарів пізньої та ранньої деревини на 68 та 47 %. Водночас на контролі відповідні величини становили 8 та 11 %. Побудовано регресійні моделі залежності індексів радіального приросту сосни від висоти нагару на стовбурах.Дендрохронологическими методами оценены последствия низового пожара 2012 г. в 53-летнемчистом сосновом насаждении в Полесье. Выявлено, что после повреждения пожаром древостоя наряду с ухудшением состояния деревьев наблюдается депрессия радиального прироста сосны, которая усиливается засухами. На основе среднеквадратичного отклонения от многолетнего хода температур и осадков (за период с 1945 по 2015 гг.) вычислены критерии, по которым определяется аномальность погодных условий. Установлены особенности формирования слоев древесины в поврежденном пожаром сосняке в зависимости от категорий санитарного состояния и классов Крафта. Уменьшение радиального прироста усиливалось с ухудшением состояния деревьев. В сравнении с допирогенным периодом произошло уменьшение слоев годичной древесины: у ослабленных деревьев на 44, очень ослабленных – на 49 и у отмирающих – на 75 %. Прирост до 2016 г. не возобновился до предпожарного состояния и сохранил четкую иерархичную тенденцию: наибольший радиальный прирост наблюдался у господствующих деревьев и соответственно меньший – у согосподствующих деревьев. В поврежденном насаждении после пожара наблюдалось уменьшение слоев поздней и ранней древесины на 68 и 47 %. В то же время на контроле соответствующие величины составили 8 и 11 %. Построены регрессионные модели зависимости индексов радиального прироста от высоты нагара на стволах.The authors have estimated the consequences of surface fire in 2012 on 50-year-old pure pine stand in Polissya by dendrochronological methods. In the course of study we have detected depression of pine radial growth that was intensified by droughts and worsening of sanitary tree state after damaging stand by forest fire. Criterias of anomality of weather conditions were calculated on basis of deviation temperature and precipitation from long-term average series of temperature and precipitation (1945-2015).Some features of formation of tree rings in damaged by fire stand including dependence on categories of sanitary state of trees and Kraft classes. Decrease of radial growth was heightened with worsening of tree state. Decrease of width tree rings was revealed at comparison period after fire with period before one: for broken trees by 44 %, very broken trees by 49 % and for dying trees by 75 %. Radial growth didn't recover till state before fire and saved clearly hierarchy tendency: dominant trees had the biggest radial growth and sub-dominant trees had less growth. In damaged stand after fire decrease of width of late (by 68 %) and early wood (by 47 %) we detected at comparison the period after fire and the period before fire. In control stand appropriate values were 8 % and 11 %. Regression model regarding dependence of index radial growth from height of deposit on stems was built

The ART-XC telescope on board the SRG observatory

ART-XC (Astronomical Roentgen Telescope - X-ray Concentrator) is the hard X-ray instrument with grazing incidence imaging optics on board the Spektr-Roentgen-Gamma (SRG) observatory. The SRG observatory is the flagship astrophysical mission of the Russian Federal Space Program, which was successively launched into orbit around the second Lagrangian point (L2) of the Earth-Sun system with a Proton rocket from the Baikonur cosmodrome on 13 July 2019. The ART-XC telescope will provide the first ever true imaging all-sky survey performed with grazing incidence optics in the 4-30 keV energy band and will obtain the deepest and sharpest map of the sky in the energy range of 4-12 keV. Observations performed during the early calibration and performance verification phase as well as during the on-going all-sky survey that started on 12 Dec. 2019 have demonstrated that the in-flight characteristics of the ART-XC telescope are very close to expectations based on the results of ground calibrations. Upon completion of its 4-year all-sky survey, ART-XC is expected to detect ~5000 sources (~3000 active galactic nuclei, including heavily obscured ones, several hundred clusters of galaxies, ~1000 cataclysmic variables and other Galactic sources), and to provide a high-quality map of the Galactic background emission in the 4-12 keV energy band. ART-XC is also well suited for discovering transient X-ray sources. In this paper, we describe the telescope, results of its ground calibrations, major aspects of the mission, the in-flight performance of ART-XC and first scientific results.Comment: 19 pages, 30 figures, accepted for publication in Astronomy and Astrophysic

The eROSITA X-ray telescope on SRG

eROSITA (extended ROentgen Survey with an Imaging Telescope Array) is the primary instrument on the Spectrum-Roentgen-Gamma (SRG) mission, which was successfully launched on July 13, 2019, from the Baikonour cosmodrome. After the commissioning of the instrument and a subsequent calibration and performance verification phase, eROSITA started a survey of the entire sky on December 13, 2019. By the end of 2023, eight complete scans of the celestial sphere will have been performed, each lasting six months. At the end of this program, the eROSITA all-sky survey in the soft X-ray band (0.2-2.3 keV) will be about 25 times more sensitive than the ROSAT All-Sky Survey, while in the hard band (2.3-8 keV) it will provide the first ever true imaging survey of the sky. The eROSITA design driving science is the detection of large samples of galaxy clusters up to redshifts z > 1 in order to study the large-scale structure of the universe and test cosmological models including Dark Energy. In addition, eROSITA is expected to yield a sample of a few million AGNs, including obscured objects, revolutionizing our view of the evolution of supermassive black holes. The survey will also provide new insights into a wide range of astrophysical phenomena, including X-ray binaries, active stars, and diffuse emission within the Galaxy. Results from early observations, some of which are presented here, confirm that the performance of the instrument is able to fulfil its scientific promise. With this paper, we aim to give a concise description of the instrument, its performance as measured on ground, its operation in space, and also the first results from in-orbit measurements

Phase transformations in Pt/Fe bilayers during post annealing probed by resistometry

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Esophageal cancer - French intergroup clinical practice guidelines for diagnosis, treatments and follow-up (TNCD, SNFGE, FFCD, GERCOR, UNICANCER, SFCD, SFED, SFRO, ACHBT, SFP, RENAPE, SNFCP, AFEF, SFR)

International audienc

SRG X-ray orbital observatory. Its telescopes and first scientific results

The orbital observatory Spectrum-Roentgen-Gamma (SRG), equipped with the grazing-incidence X-ray telescopes Mikhail Pavlinsky ART-XC and eROSITA, was launched by Roscosmos to the Lagrange L2 point of the Sun-Earth system on July 13, 2019. The launch was carried out from the Baikonur Cosmodrome by a Proton-M rocket with a DM-03 upper stage. The German telescope eROSITA was installed on SRG under an agreement between Roskosmos and the DLR, the German Aerospace Agency. In December 2019, SRG started to perform its main scientific task: scanning the celestial sphere to obtain X-ray maps of the entire sky in several energy ranges (from 0.2 to 8 keV with eROSITA, and from 4 to 30 keV with ART-XC). By mid-June 2021, the third six-month all-sky survey had been completed. Over a period of four years, it is planned to obtain eight independent maps of the entire sky in each of the energy ranges. The sum of these maps will provide high sensitivity and reveal more than three million quasars and over one hundred thousand massive galaxy clusters and galaxy groups. The availability of eight sky maps will enable monitoring of long-term variability (every six months) of a huge number of extragalactic and Galactic X-ray sources, including hundreds of thousands of stars with hot coronae. The rotation of the satellite around the axis directed toward the Sun with a period of four hours enables tracking the faster variability of bright X-ray sources during one day every half year. The chosen strategy of scanning the sky leads to the formation of deep survey zones near both ecliptic poles. The paper presents sky maps obtained by the telescopes on board SRG during the first survey of the entire sky and a number of results of deep observations performed during the flight to the L2 point in the frame of the performance verification program.(Abriged)Comment: 30 pages, 46 figures. Astronomy & Astrophysics, 656, A132, 2021. Abstract abridge

French coastal network for carbonate system monitoring: the CocoriCO2 dataset

International audienceSince the beginning of the industrial revolution, atmospheric carbon dioxide (CO2) concentrations have risen steadily and have induced a decrease of the averaged surface ocean pH by 0.1 units, corresponding to an increase in ocean acidity of about 30 %. In addition to ocean warming, ocean acidification poses a tremendous challenge to some marine organisms, especially calcifiers. The need for long-term oceanic observations of pH and temperature is a key element to assess the vulnerability of marine communities and ecosystems to these pressures. Nearshore productive environments, where a large majority of shellfish farming activities are conducted, are known to present pH levels as well as amplitudes of daily and seasonal variations that are much larger than those observed in the open ocean. Yet, to date, there are very few coastal observation sites where these parameters are measured simultaneously and at high frequency. To bridge this gap, an observation network was initiated in 2021 in the framework of the CocoriCO2 project. Six sites were selected along the French Atlantic and Mediterranean coastlines based on their importance in terms of shellfish production and the presence of high- and low-frequency monitoring activities. At each site, autonomous pH sensors were deployed, both inside and outside shellfish production areas, next to high-frequency CTD (conductivity–temperature–depth) probes operated through two operating monitoring networks. pH sensors were set to an acquisition rate of 15 min, and discrete seawater samples were collected biweekly in order to control the quality of pH data (laboratory spectrophotometric measurements) as well as to measure total alkalinity and dissolved inorganic carbon concentrations for full characterization of the carbonate system. While this network has been up and running for more than 2 years, the acquired dataset has already revealed important differences in terms of pH variations between monitored sites related to the influence of diverse processes (freshwater inputs, tides, temperature, biological processes). Data are available at https://doi.org/10.17882/96982 (Petton et al., 2023a)