19 research outputs found

    Study of the 10 micron continuum of water vapor

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    Radiation attenuation by atmospheric water vapor is considered. A formula based on laboratory data is recommended for approximating continuous absorption in the spectra region in question. Data of full scale measurements and laboratory experiments are compared. It was concluded that only molecular absorption need be taken into account under clear atmospheric conditions during the warm part of the year, while in winter or in cloudy conditions, the effect of aerosol can be significant

    Протектор микрографтов кожи в ожоговой ране: аллодерма или гидрогелевое покрытие?

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    AIM OF STUDY Was to compare the dynamics of engraftment of skin micrographs in a burn wound when using protectors from an allodermal graft and from a hydrogel coating.MATERIAL AND METHODS The experimental study was conducted on 18 rats with a scab formed 3 days after modeling a deep burn with an area of 20% of the body surface. Partial fascial necrectomy was performed: two rounded sections of the sling with a diameter of 25 mm were excised. 6 automicrographs of skin 4x4 mm, 0.3 mm thick, were applied to each surface freed from the scab. In each animal, micrographs on one of the wounds were covered with a hydrogel protector, on the other with an allodermotransplant from another animal of the group. A secondary aseptic dressing was applied to the protectors. On the 5th and 20th days after the operation, the state of micrographs was studied: blood circulation — according to laser Doppler flowmetry, microstructure in vivo — using optical coherence tomography, microstructure ex vivo — according to histological examination of biopsies.ReSUlTS Differences in the rate of restoration of blood circulation of micrographs in the early stages of the postoperative period were found. In the first 5 days, the perfusion of micrographs under an allodermal protector exceeded the indicator in micrographs under a hydrogel coating by 44 [21; 51] % (p=0.031) due to the contribution of endothelial and neurogenic mechanisms of blood flow modulation. Starting from day 10, the differences in perfusion were levelled, but there were signs of more active endothelial regulation of blood flow under the skin (p=0.028). Histologically, the appearance of full-blooded capillaries was revealed earlier in micrographs under the alloderm than when using a hydrogel protector. By 20 days, under the condition of regular change of hydrogel coatings, the area of wound healing under the studied coatings did not significantly differ. However, the structure of the integumentary tissue under the alloderm according to the optical coherence tomography data was closer to normal skin than when using a hydrogel protector.CONClUSIONS From the point of view of the physiology of the wound process, alloderm is the preferred option of an autograft protector in comparison with a hydrogel coating, which is probably due to the paracrine biological activity of the alloderm. However, hydrogel coatings can provide a comparable level of efficiency, provided they are regularly changed and, potentially, given the properties of cytokine activity.ЦЕЛЬ ИССЛЕДОВАНИЯ Сравнить динамику приживления микрографтов кожи в ожоговой ране при использовании протекторов из аллодермального трансплантата и из гидрогелевого покрытия.МАТЕРИАЛ И МЕТОДЫ Экспериментальное исследование проведено на 18 крысах, имеющих струп, сформировавшийся через 3 суток после моделирования глубокого ожога площадью 20% поверхности тела. Выполнялась частичная фасциальная некрэктомия: иссечение двух округлых участков струпа диаметром по 25 мм. На каждую поверхность, освобожденную от струпа, наносились 6 ауто­микрографтов кожи 4х4 мм толщиной 0,3 мм. У каждого животного микрографты на одной из ран закрывались гидрогелевым протектором, на другой — аллодермотрансплантатом от другого животного группы. На протекторы накладывалась вторичная асептическая повязка. На 5-е и на 20-е сутки после операции исследовалось состояние микрографтов: кровообращение — по данным лазерной допплеровской флоуметрии, микроструктура in vivo — с помощью оптической когерентной томографии, микроструктура ex vivo — по данным гистологического исследования биоптатов.РЕЗУЛЬТАТЫ Обнаружены различия в скорости восстановления кровообращения аутомикрографтов на ранних этапах послеоперационного периода. В первые 5 суток перфузия микрографтов под аллодермальным протектором превысила показатель в микрографтах под гидрогелевым покрытием на 44 [21; 51] % (р=0,031) за счет вклада эндотелиального и нейрогенного механизмов модуляции кровотока. Начиная с 10-х суток различия в перфузии нивелировались, однако сохранялись признаки более активной эндотелиальной модуляции кровотока под аллокожей (p=0,028). Гисто­логически в микрографтах под аллокожей выявлено более раннее появление полнокровных капилляров, чем при использовании гидрогелевого протектора. К 20-м суткам, при условии регулярной смены гидрогелевых покрытий, площадь заживления ран под исследуемыми покрытиями значимо не различалась. Однако структура покровной ткани под аллодермой, по данным оптической когерентной томографии, была ближе к нормальной коже, чем при использовании гидрогелевого протектора.ЗАКЛЮЧЕНИЕ С точки зрения физиологии раневого процесса аллокожа является предпочтительным вариантом протектора аутотрансплантата в сравнении с гидрогелевым покрытием, что, вероятно, обусловлено паракринной биологической активностью аллодермы.Однако гидрогелевые покрытия могут обеспечить сопоставимый уровень эффективности при условии их регулярной смены и, потенциально, придания им свойств цитокиновой активности

    First observation of Bs -> D_{s2}^{*+} X mu nu decays

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    Using data collected with the LHCb detector in proton-proton collisions at a centre-of-mass energy of 7 TeV, the semileptonic decays Bs -> Ds+ X mu nu and Bs -> D0 K+ X mu nu are detected. Two structures are observed in the D0 K+ mass spectrum at masses consistent with the known D^+_{s1}(2536) and $D^{*+}_{s2}(2573) mesons. The measured branching fractions relative to the total Bs semileptonic rate are B(Bs -> D_{s2}^{*+} X mu nu)/B(Bs -> X mu nu)= (3.3\pm 1.0\pm 0.4)%, and B(Bs -> D_{s1}^+ X munu)/B(Bs -> X mu nu)= (5.4\pm 1.2\pm 0.5)%, where the first uncertainty is statistical and the second is systematic. This is the first observation of the D_{s2}^{*+} state in Bs decays; we also measure its mass and width.Comment: 8 pages 2 figures. Published in Physics Letters

    Повышение кардиального тропонина-Т у больных без инфаркта миокарда

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    There have been recently reports on elevated levels of cardiac troponins in patients without acute myocardial infarction (AMI). The purpose of the study was to analyze final diagnoses in patients with elevated cardiac troponin-T levels without clinical manifestations and characteristic ECG changes in AMI. Subjects and materials. The study included 72 patients (48 males and 24 females whose age ranged from 54 to 87 years (mean 69.8±11.2 years)). The criterion for inclusion was increased cardiac troponin-T; the primary criteria for exclusion were AMI-specific anginal pains and characteristic ECG changes (ST-segment elevation, abnormal Q waves). The definitive diagnosis of AMI was established only in 29 (40.3%) patients; the remaining 43 patients were diagnosed as having the following diseases: sepsis (n=21), cancer (n=10), diabetic nephropathy with chronic renal failure (n=6), cerebral infarction (n=4), and B12-deficiency anemia (n=2). In deceased patients, the level of troponin-T was higher than that in those who was discharged from hospital irrespective of the underlying disease. Results. There was a direct correlation between the level of cardiac troponin-T and the SAPS II index that reflects the general condition of a patient (r=0.44; p=0.0001) and an inverse correlation between the former and the left ventricular ejection fraction (r=-0.45; p=0.003). Conclusion. Thus, despite its cardiac specificity and its detection in the blood of critically ill patients without other manifestations of AMI, cardiac troponin-T is not a specific symptom of AMI, but suggests the severity of the disease, possibly, with the involvement of the myocardium in the pathological process. Key words: cardiac troponins, myocardial infarction, multiple organ dysfunction, systemic inflammatory reaction.В настоящее время появляются сообщения о повышении уровня кардиальных тропонинов у больных без острого инфаркта миокарда (ОИМ). Цель настоящего исследования — анализ заключительных диагнозов у больных с повышением уровня кардиального тропонина-T без клинической картины и характерных изменений ЭКГ при ОИМ. Материал и методы. В исследование было включено 72 больных (48 мужчин, 24 — женщин, в возрасте от 54 до 87 лет, в среднем — 69,8±11,2). Критерием включения было повышение кардиального тропонина-Т, основными критериями исключения были — типичные для ОИМ ангинозные боли и характерные изменения ЭКГ (элевация сегмента ST, появление патологических зубцов Q). Окончательный диагноз ОИМ был установлен только у 29 больных (40,3%), у остальных 43-х больных были диагностированы следующие заболевания: у 21 — септическое состояние, у 10 — онкопатология, у 6 — диабетическая нефропа-тия с ХПН, у 4-х — инфаркт головного мозга, у 2-х — В12-дефицитная анемия. У умерших больных уровень тропонина-Т был достоверно выше, чем у выписанных из стационара, независимо от основного заболевания. Результаты. Была выявлена прямая корреляционная связь между уровнем кардиального тропонина-Т и индексом SAPS II, отражающим тяжесть общего состояния больного (r=0,44, р=0,0001) и обратная корреляционная связь между уровнем кардиального тро-понина и фракцией выброса левого желудочка (r=-0,45 р=0,003). Заключение. Таким образом, несмотря на кардиоспецифичность тропонина-Т, обнаружение его в крови пациентов, находящихся в крайне тяжелом состоянии, при отсутствии других проявлений ОИМ, не является специфическим симптомом ОИМ, а свидетельствует о тяжести заболевания, возможно с вовлечением миокарда в патологический процесс. Ключевые слова: кардиальные тропонины, инфаркт миокарда, полиорганная недостаточность, системная воспалительная реакция

    Prompt K_short production in pp collisions at sqrt(s)=0.9 TeV

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    The production of K_short mesons in pp collisions at a centre-of-mass energy of 0.9 TeV is studied with the LHCb detector at the Large Hadron Collider. The luminosity of the analysed sample is determined using a novel technique, involving measurements of the beam currents, sizes and positions, and is found to be 6.8 +/- 1.0 microbarn^-1. The differential prompt K_short production cross-section is measured as a function of the K_short transverse momentum and rapidity in the region 0 < pT < 1.6 GeV/c and 2.5 < y < 4.0. The data are found to be in reasonable agreement with previous measurements and generator expectations.Comment: 6+18 pages, 6 figures, updated author lis

    Periodicity of fires and natural regeneration of light-coniferous and sparse forests in Nadym district of the Yamal-Nenets autonomous okrug

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    Six compartments of burnt areas from different years were studied in larch, pine-larch and larch-pine dwarf shrub-moss-lichen sparse forests and light forests of the Nadym district of the Yamal-Nenets Autonomous Okrug. The new dendroсhronological method of dating of forest fires based on indicators of a variation of parameters of width of year rings is used. It showed that all biocoenoses during the life of trees were repeatedly exposed to fires, which frequency on different areas makes from 1 to 3 in a century. The beginning of the growth of new generations of trees usually comes in the years following the passing of fires and coincides with the phase of enhanced post-fire growth of the surviving instances of older generations. On all of the examined burnt areas, there is a natural regeneration of tree plants: on fresh burns (prescription of the fire 2 years) it is represented only by a vegetatively renewing birch and its self-sowing; on old ones (prescription of the fires 12, 17 and 22 years old) – the undergrowth of conifers prevails. The total number of reliable undergrowth of tree plants of all species varies in different areas from 0.7 to 10.0 thousand pcs / ha. The total number of undergrowth with an increase in the age of burnt area decreases, and older generations begin to dominate in composition. This is due to the restoration of living ground cover, which prevents the germination of tree seeds. The composition of the undergrowth and the ratio of species in it is determined by the presence of seed trees. In sparse forests, where Scotch pine is present in the composition of the remaining stand, it regenerates better than the Siberian larch, which leads to a gradual change of larch stands to pine. If there are mature the Siberian stone pine trees on the site or near it, there is an active natural regeneration of this species in the burned area

    Rapid test for the qualitative simultaneous determination of cardiac fatty acid-binding protein and cardiac troponin I in the diagnosis of acute coronary syndrome

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    Aim. To study the diagnostic characteristics of the rapid test for qualitative simultaneous determination of cardiac fatty acid-binding protein (FABPs) and cardiac troponin I (cTnI) CARD-INFO 1+1 in patients with acute coronary syndrome (ACS).Material and methods. The study included 168 patients undergoing inpatient treatment after ACS, with typical anginal pain lasting at least 20 minutes occurred in the previous 1-24 hours. In addition to routine diagnostic procedures, on admission, we determined FABPs and cTnI concentrations using the high-quality immunochromatographic rapid test CARD-INFO 1 1 (OOO CARDIO-Plus, Russia).Results. The sensitivity of the CARD-INFO 1+1 rapid test was 88,1%, specificity — 89,8%, diagnostic accuracy — 88,7%. The indicators of the diagnostic effectiveness of CARD-INFO 1+1 test in patients with STE-ACS and NSTE-ACS did not significantly differ (p&gt;0,05). The sensitivity of the rapid test reached a maximum in the period from 3 to 6 hours from the onset of pain. Compared with the determination of cTnI performed on admission to the hospital, a higher sensitivity of the CARD-INFO 1+1 test was revealed in patients with STE-ACS (87,7% vs 75,3%; p=0,044), in the first 1-3 hours after the beginning of clinical manifestations (86,8% vs 60,5%; p=0,041) and in the entire sample as a whole (88,1% vs 77,1%; p=0,033), with comparable specificity (89,8% and 93,2%, respectively; p=0,741).Conclusion. Qualitative immunochromatographic CARD-INFO 1+1 rapid test for the simultaneous determination of the content of FABPs and cTnI I is highly effective in the diagnosis of various forms of ACS. The highest diagnostic characteristics of the test were observed in patients in the early stages of the disease (the first 1-6 hours after the onset of pain). Carrying out the CARD-INFO 1+1 test revealed 12 MI cases more (11%) than the first determination of cTnI. Further studies will clarify the place of this technique in the modern algorithm for the management of patients with ACS and evaluate the possibility of using the rapid test in predicting the course of the disease
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