IAA Correlator Center

The activities of the six-station IAA RAS correlator include regular processing of national geodetic VLBI programs Ru-E, Ru-U, and Ru-F. The Ru-U sessions have been transferred in e-VLBI mode and correlated in the IAA Correlator Center automatically since 2011. The DiFX software correlator is used at the IAA in some astrophysical experiments

Effect of nonequilibrium hydrogen release in the ultrafine-grained Zr-1Nb alloy under the electron beam exposure

The evolution of structural and phase state and hydrogen release from the ultrafine-grained hydrogenated zirconium Zr-1Nb alloy during vacuum annealing and electron beams exposure were studied. The use of electron beam irradiation for hydrogen degassing is shown to decrease the temperature of active hydrogen release by 100-200 K and/or reduce the time required for hydrogen degassing from the alloy to concentrations corresponding to technical standards

Новая короновирусная инфекция (КОВИД-19) у больных туберкулезом на поздних стадиях ВИЧ-инфекции

The study materials of 23 patients with COVID-19 with newly diagnosed tuberculosis at the late stages of HIV infection with an average CD4 + cells count not exceeding 30 cells/pl of blood and in the absence of antiretroviral therapy (the main group) and 23 patients with no COVID-19 (the comparison group) and the similar parameters are presented. The presence or absence of COVID-19 is characterized by social maladjustment, drug addiction, concomitant viral hepatitis B or C and COPD, generalized tuberculosis with extrapulmonary damage of various organs and the development of other opportunistic pulmonary infections, similar clinical and radiological manifestations, which can only be differentiated by microbiological and molecular genetic research methods. To prevent exogenous infection of the healthy population with COVID-19, it is imperative to organize an active regular examination of all patients with tuberculosis and HIV infection for COVID-19, especially at the later stages, in the TB care office for HIV-infected people at TB dispensariesSunt prezentate materialele de studiu a 23 de pacienţi cu COVID-19 cu tuberculoză caz nou diagnosticată în stadiile tardive ale infecţiei HIV, cu un număr mediu de celule CD4 + care nu depăşesc 30 de celule/pl de sânge şi în absenţa terapiei antiretrovirale (grupul principal) şi 23 de pacienţi fără COVID-19 (grupul de comparaţie) şi parametrii similari. Prezenţa sau absenţa COVID-19 se caracterizează prin inadaptare socială, dependenţă de droguri, hepatită virală B sau C concomitentă şi BPOC, tuberculoză generalizată cu afectare extrapulmonară a diferitelor organe şi dezvoltarea altor infecţii pulmonare oportuniste, manifestări clinice şi radiologice similare, care poate fi diferenţiată numai prin metode de cercetare genetică microbiologică şi moleculară. Pentru a preveni infecţia exogenă a populaţiei sănătoase cu COVID-19, este imperativ să se organizeze o examinare activă regulată a tuturor pacienţilor cu tuberculoză şi HIV infecţie pentru COVID-19, în special în stadiile tardive, în biroul de supraveghere a pacienţilor cu tuberculoză infectaţi cu HIV la dispensarele TBПредставлены материалы исследования 23 больных с наличием COVID-19 с впервые выявленным туберкулезом, на поздних стадиях ВИЧ-инфекции со средним количеством CD4+ клеток не превышающем 30 кл./мкл крови и при отсутствии антиретровирусной терапии (основная группа) и 23 — с отсутствием COVID-19 (группа сравнения) и аналогичными по всем параметрам. Наличие и отсутствие COVID-19, характеризуется социальной дезадаптацией, наркозависимостью, с сопутствующим вирусным гепатитом В или С и ХОБЛ, генерализованным туберкулезом с внелегочными поражениями различных органов и развитием других оппортунистических инфекций легких, сходными клинико-рентгенологическими проявлениями, дифференцировать которые возможно только микробиологическими и молекулярно-генетическими методами исследования. Для предотвращения экзогенного заражения здорового населения COVID-19 в обязательном порядке организовать активное регулярное обследование всех больных туберкулезом и ВИЧ-инфекцией на наличие COVID-19, особенно на поздних стадиях, в кабинете противотуберкулезной помощи ВИЧ-инфицированным в ПТ

Features of clinical manifestations and diagnosis of comorbidity of disseminated pulmonary tuberculosis, coronavirus, pneumocystis and pneumococcal pneumonia in patients with late stages of HIV infection with immunodeficiency

Aim. To study the features of clinical manifestations and diagnosis of comorbidity of disseminated pulmonary tuberculosis, coronavirus, pneumocystis and pneumococcal pneumonia in patients with late stages of HIV infection with immunodeficiency. Materials and methods. The prospective study included 120 newly identified patients with disseminated pulmonary tuberculosis with Mycobacterium tuberculosis, stage IVB of HIV infection, in the phase of progression and in the absence of antiretroviral therapy, aged 2953 years, who were randomized into 1A and 2A main groups and 1B and 2B comparison groups. Group 1A included 29 patients with comorbidity and pneumocystis pneumonia and group 2A 31 patients with comorbidity of disseminated pulmonary tuberculosis, coronovirus pneumococcal pneumonia, and group 1B and 2B comprised 29 and 31 similar patients, but without coronovirus pneumonia. To diagnose coronavirus pneumonia, PCR of SARS-CoV-2 RNA was used in smears from the nasopharynx and oropharynx, in sputum or in endotracheal aspirate. To detect Pneumocystis jirovecii, the causative agent of pneumocystis pneumonia, a microscopic examination of diagnostic material from the respiratory tract with RomanovskyGiemse and GrokottGmri coloration was carried out, and to detect Streptococcus pneumoniae, the causative agent of pneumococcal pneumonia, the diagnostic material was seeded on special nutrient media with determination of the drug resistance of the resulting culture to broad-spectrum antibiotics. Statistical data processing was carried out using the Microsoft Office Excel 2019 program with the calculation of the average in the group and the standard error of the average, confidence interval. Results. The comorbidity of disseminated pulmonary tuberculosis, coronavirus, pneumocystis and pneumococcal pneumonia in patients in the late stages of HIV infection, in the phase of progression and in the absence of antiretroviral therapy was characterized by severe immunodeficiency, generalization of tuberculosis with multiple extrapulmonary lesions and severe pneumonia. This determines the similarity of clinical manifestations and respiratory symptoms, and also makes it difficult to visualize computed tomographic changes consisting of a complex simultaneous combination of four pathological syndromes: dissemination, pleural pathology, increased pulmonary pattern and adenopathy. Simultaneous layering of several pathologies with the same type of clinical manifestations and computed tomographic changes requires a comprehensive etiological diagnosis of specific diseases to prescribe timely comprehensive treatment and reduce the lethality of this heavy contingent of patients. Conclusion. Patients with disseminated pulmonary tuberculosis and HIV infection who are registered in the office of tuberculosis care for HIV-infected in the tuberculosis dispensary represent a high risk group of COVID-19 infection and the development of coronavirus pneumonia, and with severe immunodeficiency, pneumocystis and pneumococcal pneumonia, should be regularly subjected to preventive studies for timely detection of COVID-19, coronavirus, pneumocystis and pneumococcal pneumonia for the purpose of their emergency isolation and timely treatment

Structural insights into thrombolytic activity of destabilase from medicinal leech

Destabilase from the medical leech Hirudo medicinalis belongs to the family of i-type lysozymes. It has two different enzymatic activities: microbial cell walls destruction (muramidase activity), and dissolution of the stabilized fibrin (isopeptidase activity). Both activities are known to be inhibited by sodium chloride at near physiological concentrations, but the structural basis remains unknown. Here we present two crystal structures of destabilase, including a 1.1 Å-resolution structure in complex with sodium ion. Our structures reveal the location of sodium ion between Glu34/Asp46 residues, which were previously recognized as a glycosidase active site. While sodium coordination with these amino acids may explain inhibition of the muramidase activity, its influence on previously suggested Ser49/Lys58 isopeptidase activity dyad is unclear. We revise the Ser49/Lys58 hypothesis and compare sequences of i-type lysozymes with confirmed destabilase activity. We suggest that the general base for the isopeptidase activity is His112 rather than Lys58. pKa calculations of these amino acids, assessed through the 1 μs molecular dynamics simulation, confirm the hypothesis. Our findings highlight the ambiguity of destabilase catalytic residues identification and build foundations for further research of structure–activity relationship of isopeptidase activity as well as structure-based protein design for potential anticoagulant drug development.</p

Plants with genetically encoded autoluminescence

Autoluminescent plants engineered to express a bacterial bioluminescence gene cluster in plastids have not been widely adopted because of low light output. We engineered tobacco plants with a fungal bioluminescence system that converts caffeic acid (present in all plants) into luciferin and report self-sustained luminescence that is visible to the naked eye. Our findings could underpin development of a suite of imaging tools for plants

Розробка критеріального підходу до агроекологічної оцінки схилових агроландшафтів

For the forecast and management of erosion processes in order to protect the environment, information is needed on the state of its components and impact factors as well as the results of this impact. The existing methods for assessing the catchment area are mainly descriptive and cannot be used in mathematical prediction problems. The most accurate formulation of the problem of quantitative assessment of the catchment area is carried out during hydrological calculations. It seems expedient to develop theoretical prerequisites for agroecological assessment of slope agrolandscapes on the stability of a network of temporary watercourses by using the Lokhtin criterion.Slope agrolandscapes are erosive dangerous objects. The existence of a continuously changing system of microstreams generated by precipitation on slopes greatly complicates the situation. Criteria are proposed to determine the main trends in the development of watercourses of river systems by washing away or depositing soil. Conclusions about the catchment area as a whole can be obtained by examining a certain area of a microstream flow for a long time and comparing field observations with laboratory experiments. To determine the sustainability of a watercourse, a theoretically reasonable value has been proposed, which allows quantifying the network of temporary streams. When conducting research, data on the catchment area of the Tsivil river (Chuvash Republic, Russia) from 1950 to 2010 were used.A quantitative assessment of the erosion resistance of the microstream system was carried out both for periods of snowmelt and for rains, conventionally divided into summer and autumn. The theoretical background considered is confirmed by the data of long­term observations on the Great Tsivil river for sixty years. The dependences obtained make it possible to compile an adequate forecast of the direction of evolution of the catchment area in relation to the processes of soil deposition or its washing out. The criteria developed are applicable both to a specific catchment area of microstreams and to the catchment area of a river system as a wholeДля прогноза и управления процессами эрозии с целью защиты окружающей среды необходима информация о состоянии ее компонентов и факторах воздействия, а также результатах этого воздействия. Существующие методы и способы оценки водосборной площади в основном носят описательный характер и не могут быть использованы в математических задачах прогнозирования. Наиболее корректная постановка задачи по количественной оценке водосборной площади осуществляется при проведении гидрологических расчетов. Представляется целесообразным разработка теоретических предпосылок для агроэкологической оценки склоновых агроландшафтов по устойчивости сети временных водотоков с использованием критерия Лохтина.Склоновые агроландшафты являются эрозионно опасными объектами. Существование на склонах непрерывно видоизменяющейся системы микроручейков, порождаемой осадками, значительно осложняет ситуацию. Предложены критерии, определяющие основные тенденции развития русел речных систем путем смыва или наноса почвы. Выводы о водосборной площади в целом можно получить, исследовав некоторую область протекания микроручейков в течение длительного времени и сопоставив полевые наблюдения с лабораторными экспериментами. Для определения устойчивости русла предложена теоретически обоснованная величина, позволяющая дать количественную оценку сети временных водотоков. При проведении исследований использовались данные о водосборной площади реки Цивиль (Чувашская Республика, Россия) с 1950 по 2010 гг.Количественная оценка эрозионной устойчивости системы микроручейков проведена как для периодов снеготаяния, так и для дождей, условно разделенных на летние и осенние. Рассмотренные теоретические предпосылки подтверждены данными многолетних наблюдений по реке Большой Цивиль за шестьдесят лет. Полученные зависимости дают возможность составления адекватного прогноза направления эволюции водосборной площади в отношении процессов наноса почвы или ее смыва. Разработанные критерии применимы как для конкретной водосборной площади микроручейков, так и для водосборной площади речной системы в целомДля прогнозу і управління процесами ерозії з метою захисту навколишнього середовища необхідна інформація про стан її компонентів і фактори впливу, а також результати цього впливу. Існуючі методи і способи оцінки водозбірної площі в основному носять описовий характер і не можуть бути використані в математичних задачах прогнозування. Найбільш коректна постановка задачі по кількісній оцінці водозбірної площі здійснюється при проведенні гідрологічних розрахунків. Це призводить до необхідності розроблення теоретичних передумов для агроекологічної оцінки схилових агроландшафтів по стійкості мережі тимчасових водотоків з використанням критерію Лохтіна.Схилові агроландшафти є ерозійно небезпечними об'єктами. Існування на схилах системи, що безперервно видозмінюється, мікроручейків, які породжуються опадами, значно ускладнює ситуацію. Запропоновано критерії, що визначають основні тенденції розвитку русел річкових систем шляхом змиву або наносу грунту. Висновки про водозбірну площу в цілому можна отримати, дослідивши деяку область протікання мікроручейків протягом тривалого часу і зіставивши польові спостереження з лабораторними експериментами. Для визначення стійкості русла запропонована теоретично обгрунтована величина, яка дозволяє дати кількісну оцінку мережі тимчасових водотоків. При проведенні досліджень використовувалися дані про водозбірні площі річки Цивіль (Чуваська Республіка, Росія) з 1950 по 2010 рр.Кількісна оцінка ерозійної стійкості системи мікроручейків проведена як для періодів сніготанення, так і для дощів, умовно розділених на літні та осінні. Розглянуті теоретичні передумови підтверджені даними багаторічних спостережень по річці Цивіль за шістдесят років. Отримані залежності дають можливість складання адекватного прогнозу напрямку еволюції водозбірної площі щодо процесів наносу грунту або його змиву. Розроблені критерії застосовні як для конкретної водозбірної площі мікроручейків, так і для водозбірної площі річкової системи в цілом

Whistler Waves in the Plasmasphere Boundary Layer: Nonlinear Parametric Excitation

We present the initial results of numerical simulations of nonlinear coupling between quasi‐electrostatic lower hybrid oblique resonance and fast magnetosonic waves, which was suggested to explain the observations of Very Low Frequency (VLF) electromagnetic emissions at frequencies well above the lower hybrid resonance frequency in the turbulent plasmasphere boundary layer. These emissions represent a distinctive subset of the substorm/storm‐related VLF whistler activity contributing to the alteration of the outer radiation belt boundary. As the turbulent plasmasphere boundary layer is interior to the plasma sheet inner boundary and thus devoid of substorm‐injected kiloelectron volt electrons, the “standard” whistler generation mechanism must be excluded. The simulations show that the parametric coupling of lower hybrid oblique resonance and magnetosonic waves creates VLF electromagnetic emissions with the spectral characteristics consistent with the observations

Whistler Waves in the Plasmasphere Boundary Layer: Nonlinear Parametric Excitation

We present the initial results of numerical simulations of nonlinear coupling between quasi‐electrostatic lower hybrid oblique resonance and fast magnetosonic waves, which was suggested to explain the observations of Very Low Frequency (VLF) electromagnetic emissions at frequencies well above the lower hybrid resonance frequency in the turbulent plasmasphere boundary layer. These emissions represent a distinctive subset of the substorm/storm‐related VLF whistler activity contributing to the alteration of the outer radiation belt boundary. As the turbulent plasmasphere boundary layer is interior to the plasma sheet inner boundary and thus devoid of substorm‐injected kiloelectron volt electrons, the “standard” whistler generation mechanism must be excluded. The simulations show that the parametric coupling of lower hybrid oblique resonance and magnetosonic waves creates VLF electromagnetic emissions with the spectral characteristics consistent with the observations