NEAR THE ORIGINS OF MILLIMETER WAVE RADAR (90-th anniversary of Vadym В. Razskazovsky)

This paper is dedicated to the 90-th anniversary of Vadym Borysovych Razskazovsky, an outstanding scientist in the fields of radio engineering and radio science, holder of the titles and positions like DSc (Engineering), Professor, and Head of the Statistical radio physics department at the O.Ya. Usikov Institute for Radio Physics and Electronics within the Academy of Sciences of Ukraine

Improving the quality of products created by additive technologies on the basis of tig welding

В роботі розглядаються питання отримання мінімальної хвилястості поверхонь, що формуються аддитивним процесом аргонно-дугового зварювання. Відомо, що геометричні параметри валика розплаву, що пошарово формує відтво-рювану заготовку, визначаються як енергетичними, так і кінематичними характеристиками процесу. При цьому викладання валиків відбувається з оптимальним перекриттям, завдяки чому вдається досягти максимальної щільності моделі, однак з одночасним виникненням певної хвилястості, обумовленої термодинамічними явищами у ванні розплаву. Запропонована модель формування валику наплаву, завдяки якій встановлено раціональні умови викладання шарів. Наведено експериментальні дослідження процесу аргонно-дугового відтворення моделей заданої форми, отримано регресійні рівняння для визначення контрольованого параметру хвилястості. Показано, що на параметр хвилястості випливають динамічні явища та хвильові процеси, які розвиваються під дією системи сил під час формування валику наплаву. Покращення якості виробів вбачається в оптимізації способів формування валиків, забезпеченням динамічної сталості руху робочої головки, забезпеченням відповідного перекриття траєкторій руху по шарам викладання на величину 0,5 е, забезпеченням динамічної сталості руху робочої головки, встановленням раціональної довжини дуги, а також підтриманням режиму динамічної сталості горіння дуги Побудовано поверхні відгуків цільових функцій в площинах параметрів впливу, які дозволяються наглядно проілюструвати залежність контрольованих геометричних параметрів шва від окремих параметрів впливу.The paper deals with the issues of obtaining the minimum waviness of surfaces formed by additive processes of TIG welding. It is known that the geometric parameters of the melt bead, which form a reproducible workpiece layer by layer, are determined by both the energy and kinematic characteristics of the process. In this case, the laying of the rollers occurs with optimal overlap, as a result of which it is possible to achieve the maximum density of the model, however, with the simultaneous appearance of a certain waviness due to thermodynamic phenomena in the melt bath. The proposed model of the formation of a bead of melt, the use of which made it possible to establish the rational conditions for laying out the layers. Experimental studies of the process of argon-arc surfacing of models of a given, regression equations for determining the controlled waviness parameter are obtained. It is shown that the waviness parameter is influenced by dynamic phenomena and wave processes that develop under the action of a system of forces during the formation of a melt bead. An improvement in the quality of products is seen in the optimization of the methods of forming the rollers, in ensuring the dynamic stability of the movement of the working head, ensuring the appropriate overlap of the trajectories of movement along the layers of the layout by an amount of 0.5e, establishing a rational arc length, and maintaining the dynamic stability of the arc burning. The response surfaces of the objective functions in the planes of the process parameters are constructed, which provide a clear illus-tration of the dependence of the controlled geometric parameters on the welding modes.В работе рассматриваются вопросы получения минимальной волнистости поверхностей, формируемой аддитивными процессами аргонно-дуговой сварки. Известно, что геометрические параметры валика расплава, которыми послойно формируется воспроизводимая заготовка, определяются как энергетическими, так и кинематическими характеристиками процесса. При этом выкладка валиков происходит с оптимальным перекрытием, в следствие чего удается достичь максимальной плотности модели, однако с одновременным возникновением определенной волнистости, обусловленной термодинамическими явлениями в ванне расплава. Предложенная модель формирования валика расплава, использование которой позволило установить рациональны условия выкладки слоев. Приведены экспериментальные исследования процесса аргонно-дуговой наплавки моделей заданной формы, получены регрессионные уравнения для определения контролируемого параметра волнистости. Показано, что на параметр волнистости влияют динамические явления и волновые процессы, которые развиваются под действием системы сил при формировании валика расплава. Улучшение качества изделий видится в оптимизации способов формирования валиков, в обеспечении динамической устойчивости движения рабочей головки, обеспечением соответствующего перекрытия траекторий движения по слоям выкладки на величину 0,5е, установлением рациональной длины дуги, а также поддержанием режима динамической устойчивости горения дуги. Построено поверхности отклика целевых функций в плоскостях параметров процесса, которые дают наглядную иллюстрацию зависимости контролируемых геометрических параметров от режимов сварки

Objectives of the Millimetron Space Observatory science program and technical capabilities of its realization

We present the scientific program of the Spectr-M project aimed at the creation and operation of the Millimetron Space Observatory (MSO) planned for launch in the late 2020s. The unique technical capabilities of the observatory will enable broadband observations of astronomical objects from 50 μm to 10 mm wavelengths with a record sensitivity (up to ~ 0.1 μJy) in the single-dish mode and with an unprecedented high angular resolution (~ 0.1 μas) in the ground-space very long baseline interferometer (SVLBI) regime. The program addresses fundamental priority issues of astrophysics and physics in general that can be solved only with the MSO capabilities: 1) the study of physical processes in the early Universe up to redshifts z ~ 2 × 106 through measuring μ-distortions of the cosmic microwave background (CMB) spectrum, and investigation of the structure and evolution of the Universe at redshifts z < 15 by measuring y-distortions of the CMB spectrum; 2) the investigation of the geometry of space-time around supermassive black holes (SMBHs) in the center of our Galaxy and M87 by imaging surrounding shadows, the study of plasma properties in the shadow formation regions, and the search for observational manifestations of wormholes; 3) the study of observational manifestations of the origin of life in the Universe - the search for water and biomarkers in the Galactic interstellar medium. Moreover, the technical capabilities of the MSO can help solve related problems, including the birth of the first galaxies and SMBHs (z ≳ 10), alternative approaches to measuring the Hubble constant, the physics of SMBHs in 'dusty' galactic nuclei, the study of protoplanetary disks and water transport in them, and the study of 'ocean worlds' in the Solar System

Varespladib and cardiovascular events in patients with an acute coronary syndrome: the VISTA-16 randomized clinical trial

IMPORTANCE: Secretory phospholipase A2(sPLA2) generates bioactive phospholipid products implicated in atherosclerosis. The sPLA2inhibitor varespladib has favorable effects on lipid and inflammatory markers; however, its effect on cardiovascular outcomes is unknown. OBJECTIVE: To determine the effects of sPLA2inhibition with varespladib on cardiovascular outcomes. DESIGN, SETTING, AND PARTICIPANTS: A double-blind, randomized, multicenter trial at 362 academic and community hospitals in Europe, Australia, New Zealand, India, and North America of 5145 patients randomized within 96 hours of presentation of an acute coronary syndrome (ACS) to either varespladib (n = 2572) or placebo (n = 2573) with enrollment between June 1, 2010, and March 7, 2012 (study termination on March 9, 2012). INTERVENTIONS: Participants were randomized to receive varespladib (500 mg) or placebo daily for 16 weeks, in addition to atorvastatin and other established therapies. MAIN OUTCOMES AND MEASURES: The primary efficacy measurewas a composite of cardiovascular mortality, nonfatal myocardial infarction (MI), nonfatal stroke, or unstable angina with evidence of ischemia requiring hospitalization at 16 weeks. Six-month survival status was also evaluated. RESULTS: At a prespecified interim analysis, including 212 primary end point events, the independent data and safety monitoring board recommended termination of the trial for futility and possible harm. The primary end point occurred in 136 patients (6.1%) treated with varespladib compared with 109 patients (5.1%) treated with placebo (hazard ratio [HR], 1.25; 95%CI, 0.97-1.61; log-rank P = .08). Varespladib was associated with a greater risk of MI (78 [3.4%] vs 47 [2.2%]; HR, 1.66; 95%CI, 1.16-2.39; log-rank P = .005). The composite secondary end point of cardiovascular mortality, MI, and stroke was observed in 107 patients (4.6%) in the varespladib group and 79 patients (3.8%) in the placebo group (HR, 1.36; 95% CI, 1.02-1.82; P = .04). CONCLUSIONS AND RELEVANCE: In patients with recent ACS, varespladib did not reduce the risk of recurrent cardiovascular events and significantly increased the risk of MI. The sPLA2inhibition with varespladib may be harmful and is not a useful strategy to reduce adverse cardiovascular outcomes after ACS. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01130246. Copyright 2014 American Medical Association. All rights reserved

Drugs and drug-like molecules can modulate the function of mucosal-associated invariant T cells

The major-histocompatibility-complex-(MHC)-class-I-related molecule MR1 can present activating and non-activating vitamin-B-based ligands to mucosal-associated invariant T cells (MAIT cells). Whether MR1 binds other ligands is unknown. Here we identified a range of small organic molecules, drugs, drug metabolites and drug-like molecules, including salicylates and diclofenac, as MR1-binding ligands. Some of these ligands inhibited MAIT cells ex vivo and in vivo, while others, including diclofenac metabolites, were agonists. Crystal structures of a T cell antigen receptor (TCR) from a MAIT cell in complex with MR1 bound to the non-stimulatory and stimulatory compounds showed distinct ligand orientations and contacts within MR1, which highlighted the versatility of the MR1 binding pocket. The findings demonstrated that MR1 was able to capture chemically diverse structures, spanning mono- and bicyclic compounds, that either inhibited or activated MAIT cells. This indicated that drugs and drug-like molecules can modulate MAIT cell function in mammals

Objectives of the Millimetron Space Observatory Science Program and Technical Capabilities of Its Realization

We present the scientific program of the Spectr-M project aimed at the creation and operation of the Millimetron Space Observatory (MSO) planned for launch in the late 2020s. The unique technical capabilities of the observatory will enable broadband observations of astronomical objects from 50 μm to 10 mm wavelengths with a record sensitivity (up to ∼0.1 μJy) in the single-dish mode and with an unprecedented high angular resolution (∼0.1 μas) in the ground-space very long baseline interferometer (SVLBI) regime. The program addresses fundamental priority issues of astrophysics and physics in general that can be solved only with the MSO capabilities: 1) the study of physical processes in the early Universe up to redshifts z ∼ 2 106 through measuring μ-distortions of the cosmic microwave background (CMB) spectrum, and investigation of the structure and evolution of the Universe at redshifts z<15 by measuring y-distortions of the CMB spectrum; 2) the investigation of the geometry of space-time around supermassive black holes (SMBHs) in the center of our Galaxy and M87 by imaging surrounding shadows, the study of plasma properties in the shadow formation regions, and the search for observational manifestations of wormholes; 3) the study of observational manifestations of the origin of life in the Universe - the search for water and biomarkers in the Galactic interstellar medium. Moreover, the technical capabilities of the MSO can help solve related problems, including the birth of the first galaxies and SMBHs (z ⪆ 10), alternative approaches to measuring the Hubble constant, the physics of SMBHs in 'dusty' galactic nuclei, the study of protoplanetary disks and water transport in them, and the study of 'ocean worlds' in the Solar System. © 2021 Uspekhi Fizicheskikh Nauk, Russian Academy of Sciences and IOP Publishing.We appreciate the referees for their critical notes.Thestudy was partially supported by the project New Scientific Groups of LPI, no. 41-2020. AP thanks the RSF for its support (project 19-72-00064). AB is supported by RSF grant 18-12-00351 and by the State Target FEUZ-2020-0038. The work by IZ (Section 4) is supported by RFBR grant 18-02-00660. DV was supported by a grant from the Russian Government and Ministry of Higher Education and Science, 075-15-2020-780 (no. 13.1902.21.0039). The work by VSh (Section 4.4) was supported by a grant from the Russian Government for research by leading scientists under the program Studies of Stars with Exoplanets (agreement 075-15-2019-1875)

Diagnosis and Treatment of Irritable Bowel Syndrome: Clinical Recommendations of the Russian Gastroenterological Association and Association of Coloproctologists of Russia

Aim. Current clinical recommendations accentuate current methods for the diagnosis and treatment of irritable bowel syndrome (IBS).Key points. IBS is a functional bowel disorder manifested with recurrent, at least weekly, abdominal pain with the following attributes (any two leastwise): link to defecation, its frequency or stool shape. The symptoms are expected to persist for at minimum three months in a total six-month follow-up. Similar to other functional gastrointestinal (GI) disorders, IBS can be diagnosed basing on the patient symptoms compliance with Rome IV criteria, provided the absence of potentially symptom-causative organic GI diseases. Due to challenging differential diagnosis, IBS can be appropriately established per exclusionem, with pre-examination as follows: general and biochemical blood tests; tissue transglutaminase IgA/IgG antibody tests; thyroid hormones test; faecal occult blood test; hydrogen glucose/ lactulose breath test for bacterial overgrowth; stool test for enteric bacterial pathogens and Clostridium difficile A/B toxins; stool calprotectin test; abdominal ultrasound; OGDS, with biopsy as appropriate; colonoscopy with biopsy. The IBS sequence is typically wavelike, with alternating remissions and exacerbations often triggered by psychoemotional stress. Treatment of IBS patients includes dietary and lifestyle adjustments, various-class drug agents prescription and psychotherapeutic measures.Conclusion. Adherence to clinical recommendations can facilitate timely diagnosis and improve medical aid quality in patients with different clinical IBS variants

Extended Thromboprophylaxis with Betrixaban in Acutely Ill Medical Patients

Background Patients with acute medical illnesses are at prolonged risk for venous thrombosis. However, the appropriate duration of thromboprophylaxis remains unknown. Methods Patients who were hospitalized for acute medical illnesses were randomly assigned to receive subcutaneous enoxaparin (at a dose of 40 mg once daily) for 10±4 days plus oral betrixaban placebo for 35 to 42 days or subcutaneous enoxaparin placebo for 10±4 days plus oral betrixaban (at a dose of 80 mg once daily) for 35 to 42 days. We performed sequential analyses in three prespecified, progressively inclusive cohorts: patients with an elevated d-dimer level (cohort 1), patients with an elevated d-dimer level or an age of at least 75 years (cohort 2), and all the enrolled patients (overall population cohort). The statistical analysis plan specified that if the between-group difference in any analysis in this sequence was not significant, the other analyses would be considered exploratory. The primary efficacy outcome was a composite of asymptomatic proximal deep-vein thrombosis and symptomatic venous thromboembolism. The principal safety outcome was major bleeding. Results A total of 7513 patients underwent randomization. In cohort 1, the primary efficacy outcome occurred in 6.9% of patients receiving betrixaban and 8.5% receiving enoxaparin (relative risk in the betrixaban group, 0.81; 95% confidence interval [CI], 0.65 to 1.00; P=0.054). The rates were 5.6% and 7.1%, respectively (relative risk, 0.80; 95% CI, 0.66 to 0.98; P=0.03) in cohort 2 and 5.3% and 7.0% (relative risk, 0.76; 95% CI, 0.63 to 0.92; P=0.006) in the overall population. (The last two analyses were considered to be exploratory owing to the result in cohort 1.) In the overall population, major bleeding occurred in 0.7% of the betrixaban group and 0.6% of the enoxaparin group (relative risk, 1.19; 95% CI, 0.67 to 2.12; P=0.55). Conclusions Among acutely ill medical patients with an elevated d-dimer level, there was no significant difference between extended-duration betrixaban and a standard regimen of enoxaparin in the prespecified primary efficacy outcome. However, prespecified exploratory analyses provided evidence suggesting a benefit for betrixaban in the two larger cohorts. (Funded by Portola Pharmaceuticals; APEX ClinicalTrials.gov number, NCT01583218. opens in new tab.

Diagnosis and Treatment of Irritable Bowel Syndrome: Clinical Recommendations of the Russian Gastroenterological Association and Association of Coloproctologists of Russia

Aim. Current clinical recommendations accentuate current methods for the diagnosis and treatment of irritable bowel syndrome (IBS).Key points. IBS is a functional bowel disorder manifested with recurrent, at least weekly, abdominal pain with the following attributes (any two leastwise): link to defecation, its frequency or stool shape. The symptoms are expected to persist for at minimum three months in a total six-month follow-up. Similar to other functional gastrointestinal (GI) disorders, IBS can be diagnosed basing on the patient symptoms compliance with Rome IV criteria, provided the absence of potentially symptom-causative organic GI diseases. Due to challenging differential diagnosis, IBS can be appropriately established per exclusionem, with pre-examination as follows: general and biochemical blood tests; tissue transglutaminase IgA/IgG antibody tests; thyroid hormones test; faecal occult blood test; hydrogen glucose/ lactulose breath test for bacterial overgrowth; stool test for enteric bacterial pathogens and Clostridium difficile A/B toxins; stool calprotectin test; abdominal ultrasound; OGDS, with biopsy as appropriate; colonoscopy with biopsy. The IBS sequence is typically wavelike, with alternating remissions and exacerbations often triggered by psychoemotional stress. Treatment of IBS patients includes dietary and lifestyle adjustments, various-class drug agents prescription and psychotherapeutic measures.Conclusion. Adherence to clinical recommendations can facilitate timely diagnosis and improve medical aid quality in patients with different clinical IBS variants