The optical identifcation of events with poorly defined locations: The case of the Fermi GBM GRB140801A

We report the early discovery of the optical afterglow of gamma-ray burst (GRB) 140801A in the 137 deg$^2$ 3-$\sigma$ error-box of the Fermi Gamma-ray Burst Monitor (GBM). MASTER is the only observatory that automatically react to all Fermi alerts. GRB 140801A is one of the few GRBs whose optical counterpart was discovered solely from its GBM localization. The optical afterglow of GRB 140801A was found by MASTER Global Robotic Net 53 sec after receiving the alert, making it the fastest optical detection of a GRB from a GBM error-box. Spectroscopy obtained with the 10.4-m Gran Telescopio Canarias and the 6-m BTA of SAO RAS reveals a redshift of $z=1.32$. We performed optical and near-infrared photometry of GRB 140801A using different telescopes with apertures ranging from 0.4-m to 10.4-m. GRB 140801A is a typical burst in many ways. The rest-frame bolometric isotropic energy release and peak energy of the burst is $E_\mathrm{iso} = 5.54_{-0.24}^{+0.26} \times 10^{52}$ erg and $E_\mathrm{p, rest}\simeq280$ keV, respectively, which is consistent with the Amati relation. The absence of a jet break in the optical light curve provides a lower limit on the half-opening angle of the jet $\theta=6.1$ deg. The observed $E_\mathrm{peak}$ is consistent with the limit derived from the Ghirlanda relation. The joint Fermi GBM and Konus-Wind analysis shows that GRB 140801A could belong to the class of intermediate duration. The rapid detection of the optical counterpart of GRB 140801A is especially important regarding the upcoming experiments with large coordinate error-box areas.Comment: in press MNRAS, 201

Гидрологическая характеристика озёр восточной части полуострова Брокнес, холмы Ларсеманн, Восточная Антарктида

Broknes Peninsula (the area of the Progress station, Larsemann Hills, Princess Elisabeth Land, East Antarctica) is characterized by the presence of well developed hydrographic network consisting of reservoirs located not only in the bedrock, but also inside the glacier thickness and on its surface. As a rule, most of them are dammed by natural snowice weirs, which are often destroyed during the Antarctic summer. As a result of this process, glacial water outburst may occur. In the course of the summer season of the 63‑th Russian  Antarctic Expedition (RAE) intensive hydrological field observations were carried out for identification and comprehensive investigation of potentially outburstprone reservoirs located in close proximity to Russian and foreign stations and field bases (area of the  Progress station and the field base Law-Racovita). The works included: the organization of temporary pile and depth-stick water gauge stations, mapping positions of the shoreline of lakes (reservoirs), bathymetric surveys of them, as well as field hydro-chemical express analyses. Based on the results of the level measurement, it was found that most of the lakes of the oasis are characterized by a sharp drop in the height of the water surface level associated with the breakthroughs. In particular, the authors witnessed the breakthrough of the Discussion Lake, which occurred on January 22, 2018. This resulted in decrease of the water level by 0.95 m. Based on the data of the bathymetric surveys, the morphometric (hydrometric) characteristics of the lakes were calculated and detailed grids (regular net of rectangular matrices, in the nodes of which some effective values of the mapped values are located) were formed for the following numerical modeling of hypothetical and real breakthroughs of water bodies and construction of estimated hydrographs.Приведены результаты гидрологических исследований прорывоопасных озёр, расположенных недалеко от отечественных и зарубежных станций и полевых баз. Установлены основные прорывоопасные водоёмы и сформированы подробные гриды (регулярная сеть прямоугольных матриц, в узлах которых располагаются значения картируемых величин) исследуемых водных объектов для проведения математического моделирования

Основные факторы формирования субаэральных таликов в рамках одномерной математической модели на примере района реки Шестаковка, Центральная Якутия

This study presents a mathematical model of heat transfer in a subaerial talik. The model is based on the concepts presented in classical works on permafrost, as well as on the results of geological and geophysical research carried out in the Shestakovka River basin (Central Yakutia). This model is based on the solution of the classical Stefan problem on the moving of the phase transition boundaries for a multilayer and multiphase medium. The solution was calculated on a unstructured mesh. When the phase boundaries move, thawed or frozen layers of soil are formed or wedged out. The layers include: snow cover, seasonally thawed soil, seasonally frozen and frozen sand deposits, as well as soil-vegetative layer. Published empirical relationships were used to calculate thermophysical coefficients, which are presented in this article. Simple variants of the model were considered to clarify the contribution of various factors to the process of formation and evolution of taliks. It has been established that the presence of snow cover and soil-vegetative layer have the most significant effect on the formation of taliks. Calculations show that taliks are formed in the first years of the modeled period, in the presence of snow and the absence of soil-vegetative layer. The soil-vegetative layer, depending on its composition and moisture content (ice content), can prevent the formation and development of taliks. The authors do not consider cases where shrubs contribute to snow accumulation. The humidity and iciness of the layer of sand sediments located in Central Yakutia have practically no effect on this process.На основе математического моделирования и численных экспериментов дана оценка влияния разных факторов на формирование и термический режим субаэральных таликов. Различные модельные сценарии показали, что наибольший вклад в формирование и развитие таликов вносит снежный покров, препятствующий выхолаживанию грунта в зимний период. Наличие напочвенного слоя с определенными теплофизическими параметрами может препятствовать формированию талика. Рассмотрено влияние теплофизических параметров напочвенных покровов на формирование талика

Состояние взлётно-посадочной полосы станции Новолазаревская (Восточная Антарктида) и оценка безопасности её эксплуатации по данным исследований 2021 г.

Airbase Novo Runway has the status of the largest transport hub in the northern part of Antarctica, which can land large airlifter on wheeled chassis. However, the unsteady flow of the glacier leads both to the formation of hazardous glacial crevasses and changes the configuration of the runway. The purpose of this study was to investigation the state of the Novo Runway and to identify the degree of uneven flow of the glacier in this area. The article shows the results of research carried out from late October to mid-December 2021. Field work included GPR profiling, tacheometric survey, mechanical drilling, and downhole thermometry. The tacheometric survey was carried out at the beginning and at the end of the field work (in 42 days) to determine the displacements of pickets fixed on the glacier and then to calculate the glacier deformation rates. The results of the studies showed that there are no open crevasses in this area, which pose a danger to aircraft. There are non-hazardous healed crevasses at the beginning and end of the runway. At the same time, GPR data indicate that in the central part of the runway (at the distances from 1720 meters to 2240 meters from its beginning), there is a zone of junction of glacial flows. This zone is traced on parallel profiles for more than one kilometer. Calculation results indicate that the strain rates in this area in the transverse direction (across the runway) reaches -0.183 year-1. This corresponds to deformations (compressions) of more than 1.4 meters over 42 days of observations in absolute terms. Although these values significantly exceed the threshold values, there were no open crevasses in the glacier. It can be assumed that relatively recently the glacier flowed more slowly than now. This research should be continued to draw broader conclusions about the dynamics of the glacier in the area of the Novo Runway.Рассмотрены результаты комплексных инженерных изысканий, выполненных на посадочной площадке станции Новолазаревская в сезон 2021/22 г. Установлено, что в центральной части взлётно-посадочной полосы наблюдается сочленение двух ледовых потоков. Абсолютные скорости деформаций ледника на этом участке достигают -0,183 год-1, что существенно превышает пороговые значения, однако открытых трещин в леднике не наблюдалось

Прорыв озера Прогресс (Восточная Антарктида): подходы к оценке характеристик прорывного паводка

On January 14, 2019, a breakthrough of water masses occurred on the Lake Progress (the oasis of the Larsemann hills, East Antarctica) with the formation of a flash flood. During the summer field seasons of the 63rd and 64th Russian Antarctic Expeditions (2017–2019), comprehensive hydrological, GPR and geodetic surveys were conducted in this area to ensure the safety of transport operations. The results of field measurements and calculations based on mathematical modeling of the breakthrough flood from the Lake are presented. The purpose of this study was to compare field observations and model calculations of the breakthrough flood and then to verify the existing model of Yu.B. Vinogradov on real data, since detailed observations of breakthrough floods of lakes of the Antarctic oases have not been previously carried out. The results of complex hydrological and geophysical investigations of LH73–Progress–Sibtorp lake system focused on areas where lake outburst are possible (snow-ice dams) made possible to formulate phenomenological model of the outburst process. It was emphasized that the lake water was discharged through a tunnel developed in the snow–ice dam, which subsequently evolved into a real riverbed. The maximum water discharge was formed approximately in 7.5 h after the start of the outflow, and it was estimated 5.4 m3s-1 according to the in-situ measurements, and 4.94 m3s-1 – by the model. The calculated volume of the flood is 76 320 m3. The differences between the model and in-situ measurements are about 9% that can be explained by the fact that the time of water retention by the snow-ice dam is not considered in the model.При исследованиях в 2018/19 г. в районе станции Прогресс (Восточная Антарктида) авторы наблюдали прорыв системы озёр Прогресс–Сибторп. Приводятся феноменологическое описание этого процесса, а также результаты наблюдений и математического моделирования

Эпидемиология и исходы респираторного дистресса у новорожденных

Respiratory distress of newborns is one of the most frequent causes of infant admission to intensive care units, the development of severe complications of the neonatal period and lethal outcomes.The objective was to study the epidemiology and outcomes of respiratory distress in newborns requiring intensive care measures.Materials and methods. The design was a retrospective observational study. We examined 180 newborns, the mean weight was 1620 (1075–2197.5) g, and the gestational age was 31.8 (29–34.5) weeks. Apgar score at minute 1 was 5 (4–7) and at minute 5 was 7 (6–7) scores. The duration of artificial lung ventilation was 2 (12.5–242) hours, and the duration of treatment in the NICU was 10 (6–19) days. Lethal outcomes occurred in 6 (3%) cases.Results. The most frequent cause of respiratory distress in newborns was respiratory distress syndrome in newborns (53%). The second place was occupied by asphyxia in childbirth (31%). Intra-amniotic infection was detected in 11 (6%) newborns, and intrauterine pneumonia in 5 (3%) infants. Transient tachypnea was registered in 6 (3%) newborns, and meconium aspiration syndrome – in 8 (4%) patients. In premature infants, the most severe course of respiratory distress was noted in pneumonia and asphyxia, in mature infants – in meconium aspiration syndrome. The maximum duration of intensive care measures was observed in intra-amniotic infection – 16 days and respiratory distress syndrome – 11 days. The outcome in 47% was favorable – complete recovery. Unfavorable outcomes included intraventricular hemorrhage (12%), combination of two or more complications (20%), bronchopulmonary dysplasia (5%), and persistent arterial ductus (4%).Conclusion. The outcome of respiratory distress in newborns with adequate assessment of the severity of the condition and timely initiated evidence-based treatment is determined not by the main clinical diagnosis, but by the gestational age and severity of the infant condition at the time of birth.Респираторный дистресс новорожденных (РДН) является одной из наиболее частых причин поступления детей в отделения интенсивной терапии, развития тяжелых осложнений неонатального периода и летальных исходов.Цель – изучить эпидемиологию и исходы респираторного дистресса у новорожденных, нуждающихся в мероприятиях интенсивной терапии.Материалы и методы. Дизайн – ретроспективное обсервационное исследование. Обследовано 180 новорожденных, средний вес которых составил 1620 (1075–2197,5) г, а гестационный возраст – 31,8 (29–34,5) недель. Оценка по шкале Апгар на 1 мин была 5 (4–7), на 5–7 (6–7) баллов. Продолжительность ИВЛ была равна 2 (12,5–242) ч, а длительность лечения в ОРИТН составила 10 (6–19) суток. Летальные исходы имели место в 6 (3%) случаях.Результаты. Наиболее частой причиной РДН был респираторный дистресс-синдром новорожденных (53%). Второе место занимала асфиксия в родах (31%). Внутриамниотическая инфекция выявлена у 11 (6%) новорожденных, а внутриутробная пневмония – у 5 (3%) детей. Транзиторное тахипноэ зарегистрировано у 6 (3%) новорожденных, а синдром аспирации мекония – у 8 (4%) пациентов. У недоношенных новорожденных наиболее тяжелое течение респираторного дистресса отмечалось при пневмонии и асфиксии, у доношенных детей – при синдроме аспирации мекония. Максимальная продолжительность мероприятий интенсивной терапии была отмечена при внутриамниотической инфекции – 16 суток и респираторном дистресс-синдроме – 11 суток. Исход в 47% случаев был благоприятный – полное выздоровление. Среди неблагоприятных исходов преобладали внутрижелудочковое кровоизлияние (12%), сочетание 2 и более осложнений – (20%), бронхолегочная дисплазия (5%) и персистирование артериального протока (4%).Заключение. Исход респираторного дистресса у новорожденных при адекватной оценке тяжести состояния и своевременно начатом обоснованном лечении определяется не основным клиническим диагнозом, а сроком гестации и тяжестью состояния ребенка на момент рождения

Геофизические изыскания в районе станции Прогресс, Восточная Антарктида, в сезон 63-й РАЭ (2017/18 г.)

In recent years, when organizing works of the Russian Antarctic Expedition (RAE), considerable attention is given to the safety of logistics operations carried out at Russian stations and field bases. The main factors that threaten polar explorers are extensive systems of cracks and water breakthroughs, confined to the marginal, the most dynamic part of the outlet glaciers, in the area of which the most part of stations are located. One example of the impact of these processes on transport communications in Antarctica is the breakthrough of an intraglacial reservoir in the Dolk glacier near the station Progress (Larsemann Hills, Eastern Antarctica) in the season of the 62nd RAE (2016/17). The outburst resulted in the formation of a huge hole in the glacier body and an extensive system of cracks directed towards its flanks. This took place on the part of the route connecting the Progress Station with the point of organization the sledge-tractor train marches to inner regions of the Antarctic continent. Thus, this destroyed the transport links between these points. That is why during the seasonal works of the 63rd RAE (2017/18) geophysical surveys were carried out around the hole by means of the GPR profiling for the purpose to find the best way and organize a new all-season route. The GPR soundings performed at frequencies of 900 and 150 MHz, made possible to fix numerous cracks and large volumes of melt water accumulations in the near-surface part of the ice layer. The analysis of the obtained time sections and the assessment of the depths of cracks and watered areas did show that the detected objects in the glacier body were not dangerous for advancing of the sledge-caterpillar equipment passing by the hole. These surveys allowed planning the optimal new route, after which it was rolled up and put into operation. The logistical connection between the station and the airfield has been restored. Until the end of the field season, the new all-season route was actively used for transportation.Представлены результаты исследований в районе Холмов Ларсеманн на участке ледника Долк в поисках безопасного места для организации новой всесезонной трассы с целью возобновления транспортного сообщения между станцией Прогресс, аэродромом и пунктом формирования санно‑гусеничных походов, прерванного в результате образования провала в леднике Долк

Actual aspects of etiological diagnostics of tick-borne infections in Ural region

Etiological decoding was produced of infections transmitted by Ixodes ticks. 142 patients (adults and children) with a fever of unknown etiology or tick bite history of being in the hospital with symptoms of infection was investigate serological methods (ELISA, IgM and IgG). IgM of tick-borne encephalitis virus is found in 17 patients (35.4%), of Ixodes tick borreliosis agents in one (2%), of human granulocytic anaplasmosis pathogen in two (4%). IgM is not revealed of monocytic ehrlichiosis agents person. IgM were determined simultaneously not only to the tick-borne encephalitis virus and Ixodes tick borreliosis pathogens, but also to Anaplasma phagocytophilum in 8.3% patients.Произведена этиологическая расшифровка заболеваний, передающихся иксодовыми клещами, у 142 пациентов (детей и взрослых) с лихорадкой неясной этиологии или укусом клеща в анамнезе, находящихся в стационаре с признаками инфекционного заболевания, с помощью серологического метода (ИФА, IgM и IgG). IgM к вирусу клещевого энцефалита обнаружен у 17 пациентов (35,4%), к возбудителям иксодового клещевого боррелиоза — у одного (2%), к возбудителю гранулацитарного анаплазмоза человека — у двоих (4%). IgM к возбудителям моноцитарного эрлихиоза человека не выявлены. Одномоментно IgM определялись не только к вирусу клещевого энцефалита и возбудителям иксодового клещевого боррелиоза, но и к Anaplasma phagocytophilum у 8,3% пациентов

Diagnosis of catheter-associated bloodstream infections

238 catheters from 220 children were studied mainly from the surgical, intensive care and oncohematological departments. For the diagnosis of catheter-associated bloodstream infections used semiquantitative method inoculation catheters by D. Maki and blood culture isolation of intact vein. Share colonized or locally infected catheters was 79.2%, catheter-associated bloodstream infections – 20.8%.Исследовано 238 проб катетеров от 220 детей, преимущественно из хирургических, реанимационных и онкогематологических отделений. Для диагностики катетер-ассоциированных инфекций кровотока применяли полуколичественный метод посева катетера по D. Maki и выделение гемокультуры из интактной вены. Доля колонизированных или локально инфицированных катетеров составила 79,2%, катетер-ассоциированных инфекций кровотока — 20,8%

Aetiology of infectious complications in children with oncohematological diseases

The article presents the results of microbiological studies of different biomaterials in the diagnosis of infectious complications in children with oncohematologicaldiseases after bone marrow transplantation.Gram-negative bacteria both endogenous and possibly nosocomial origin are lead among the detected microorganisms.В статье приведены результаты микробиологических исследований различных биоматериалов, полученных при диагностике инфекционных осложнений у детей с онкогематологическими заболеваниями после трансплантации. Среди обнаруженных микроорганизмов лидируют грамотрицательные бактерии как эндогенного, так и, возможно, нозокомиального происхождения