186 research outputs found

    Approach to conceptual modeling national scientific and technological potential

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    The paper presents a conceptual multilevel model of national scientific and technological potential in order to form and select options for the strategy of innovative development of the country. The model is based on the methodology of group verbal decision analysis and multidimensional assessment of innovations. The elements of the information-logical model and the intensity of connections between elements of different levels are evaluated by experts on qualitative criteria with verbal scale

    Null Energy Condition Violation and Classical Stability in the Bianchi I Metric

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    The stability of isotropic cosmological solutions in the Bianchi I model is considered. We prove that the stability of isotropic solutions in the Bianchi I metric for a positive Hubble parameter follows from their stability in the Friedmann-Robertson-Walker metric. This result is applied to models inspired by string field theory, which violate the null energy condition. Examples of stable isotropic solutions are presented. We also consider the k-essence model and analyse the stability of solutions of the form Φ(t)=t\Phi(t)=t.Comment: 27 pages, references added, accepted for publication in Phys. Rev.

    Approaches to defining scientific priorities in healthcare and medicine: the Russian experience

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    This paper describes the system of organization and management for healthcare and medical science in Russia. The procedures for forming scientific priorities in medicine in the post-Soviet period are described. The necessity of applying modern methods in the selection of scientific priorities is substantiate

    Global solutions of a free boundary problem for selfgravitating scalar fields

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    The weak cosmic censorship hypothesis can be understood as a statement that there exists a global Cauchy evolution of a selfgravitating system outside an event horizon. The resulting Cauchy problem has a free null-like inner boundary. We study a selfgravitating spherically symmetric nonlinear scalar field. We show the global existence of a spacetime with a null inner boundary that initially is located outside the Schwarzschild radius or, more generally, outside an apparent horizon. The global existence of a patch of a spacetime that is exterior to an event horizon is obtained as a limiting case.Comment: 31 pages, revtex, to appear in the Classical and Quantum Gravit

    Antegrade lithoextraction as perspective technique for mechanical jaundice radical treatment

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    Objective. Improvement of treatment outcomes in patients with the cholelithiasis complicated by mechanical jaundice when it is impossible to apply retrograde techniques for biliary tract decompression.Material and Methods. From 2014 to 2017 in our hospital 1158 patients with cholelithiasis complicated by mechanical jaundice have been treated. The group consisted of 59 (5.1%) patients with initially predicted difficulties for endoscopic lithoextraction. In 12 of that group antegrade decompression was the only surgical method for completing treatment. In 2 cases the ‘rendezvous’ technique was used, and in 23 patients the antegrade decompression it was complemented with laparotomy and choledocholithotomy. In 22 patients for verification the nature of the bile-excreting ducts and the cholelithic occlusion revealed at the same time the first stage included an antegrade decompression that allowed to finish surgical treatment by an endoscopic transpapillary lithoextraction.Results. In the main group of clinical observations for 59 patients the surgical treatment complemented with an antegrade decompression was without fatal outcomes. All patients were cured of cholelithic occlusion and recovered. In the study group with 1099 patients that were treated with only an endoscopic lithoextraction 8 patients died that showed 0.7 ± 0.2% of operational mortality. Complications, in the form of operational wounds in the main group of observations were found in 7 patients and it was 11.8 ± 4.2%. Other postoperative complications in the main group were not observed. In the control group similar wound complications were seen in 13 patients (1.2%). In the control group with 57 patients we observed intraabdominal complications which resulted in mortality (5.2 ± 0.7%). Of those postoperative reversible pancreatitis was found in 34 patients, 3 patients had fulminant pancreonecrosis, in 4 cases there was profuse bleeding from a papillosphincterotomy area, in 3 cases we observed insertion of Dormia basket at lithoextraction, septic cholangitis was in 11 and duodenum perforation with retroperitoneal phlegmon was in 3 cases.Conclusion. Mortality in the group with antegrade treatment application for choledocholithiasis was not found. On the contrary, rather higher rate of complications in the control group testifies in advantage of the antegrade techniques for choledocholithiasis treatment in the shown cases

    Changes in cytokine production in healthy subjects practicing Guolin Qigong : a pilot study

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    BACKGROUND: Guolin Qigong is a combination of meditation, controlled breathing and physical movement designed to control the vital energy (qi) of the body and consequently to improve spiritual, physical and mental health. Practice of Qigong has been reported to alter immunological function, but there have been few studies of its effects on cytokines, the key regulators of immunity. METHODS: Numbers of peripheral blood cytokine-secreting cells were determined by ELISPOT in 19 healthy volunteers aged 27 – 55, before they were taught the practice of Qigong and after 3, 7 and 14 weeks of daily practice. The effect of Qigong on blood cortisol was also examined. RESULTS: Numbers of IL4 and IL12-secreting cells remained stable. IL6 increased at 7 weeks and TNFα increased in unstimulated cultures at 3 and 7 weeks but decreased at these times in LPS and SAC-stimulated cultures. Of particular interest, IFNγ-secreting cells increased and IL10-secreting cells decreased in PHA-stimulated cultures, resulting in significant increases in the IFNγ:IL10 ratio. Cortisol, a known inhibitor of type 1 cytokine production, was reduced by practicing Qigong. CONCLUSION: These preliminary studies in healthy subjects, although not necessarily representative of a randomized healthy population and not including a separate control group, have indicated that blood levels of the stress-related hormone cortisol may be lowered by short-term practice of Qigong and that there are concomitant changes in numbers of cytokine-secreting cells. Further studies of the effect of Qigong in patients with clinical diseases known to be associated with type 2 cytokine predominance are merited

    Invariant construction of solutions to Einstein's field equations - LRS perfect fluids II

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    The properties of LRS class II perfect fluid space-times are analyzed using the description of geometries in terms of the Riemann tensor and a finite number of its covariant derivatives. In this manner it is straightforward to obtain the plane and hyperbolic analogues to the spherical symmetric case. For spherically symmetric static models the set of equations is reduced to the Tolman-Oppenheimer-Volkoff equation only. Some new non-stationary and inhomogeneous solutions with shear, expansion, and acceleration of the fluid are presented. Among these are a class of temporally self-similar solutions with equation of state given by p=(γ1)μ,1<γ<2p=(\gamma-1)\mu, 1<\gamma<2, and a class of solutions characterized by σ=Θ/6\sigma=-\Theta/6. We give an example of geometry where the Riemann tensor and the Ricci rotation coefficients are not sufficient to give a complete description of the geometry. Using an extension of the method, we find the full metric in terms of curvature quantities.Comment: 24 pages, 1 figur

    Meglumine Sodium Succinate to Correct COVID-19-Associated Coagulopathy: the Feasibility Study

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    Aim of the study: to evaluate the effect of meglumine sodium succinate (MSS) on the efficacy of anticoagulant therapy in patients with severe COVID-19 infection complicated by bilateral community-acquired pneumonia.Materials and methods. Overall efficacy of treatment was analyzed in 12 patients hospitalized to ICU with the diagnosis of severe confirmed COVID-19 coronavirus infection (U07.1) complicated by bilateral multisegmental pneumonia. All patients received prophylactic anticoagulation with unfractionated heparin. The patients were divided into two groups: 7 of them received a multi-electrolyte solution containing MSS 5 ml/kg daily for the entire ICU stay (3-10 days) as a part of therapy; 5 patients received a similar volume of a conventional multi-electrolyte solution containing no metabolically active substrates and comprised a control group. Coagulation parameters were measured in arterial and venous blood of all patients at the following stages: 1) upon admission to the ICU; 2) 2-4 hours after the first dose of heparin; 3) 8-12 hours after the second dose of heparin; 4) 24 hours after the beginning of intensive therapy. On the 28th day of follow-up, mortality, duration of ICU stay, and incidence of thrombotic complications in the groups were evaluated. Nonparametric methods of statistical analysis were used to assess intragroup changes and intergroup differences.Results. The group of patients administered with MSS had significantly fewer thromboembolic events during 28 days of treatment and shorter ICU stay. These patients responded faster to anticoagulant therapy, which was suggested by more distinct changes in coagulation parameters, i.e. increased APTT, persisting viable thrombocyte population, reduced D-dimer and fibrinogen levels.Conclusion. The metabolic action of succinate possibly increases endothelial resistance to damaging factors and reduces its procoagulant activity. The hypothesis requires testing in a larger clinical study with a design including laboratory evaluation of the efficacy of varying doses of the studied drug as well as aiming at elucidation of the mechanisms of its effect on specific pro- and anticoagulation system components

    Гиперреактивность дыхательных путей при бронхиальной астме: основы патогенеза

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    Bronchial asthma has three main components: persistent bronchial inflammation, reversible bronchial obstruction and bronchial hyperresponsiveness to nonspecific triggers. Airway hyperresponsiveness is a complex phenomenon that develops upon the influence of chronic inflammation, high total IgE, changes in bronchial smooth muscle cells functioning, structural changes in bronchial wall and disturbances in neural regulation of bronchial tone.Известно, что бронхиальная астма характеризуется наличием двух основных патогенетических составляющих — это персистирующее хроническое воспаление в бронхах и бронхиальная гиперреактивность к различным неспецифическим триггерам. Формирование бронхиальной гиперреактивности при бронхиальной астме взаимосвязано с персистирующим воспалением стенки бронхиального дерева, высоким уровенем IgE в сыворотке крови, изменением функции гладкой мускулатуры бронхов, наличием структурных изменений стенки бронхиального дерева, а также нарушением нейрорегуляции бронхомоторного тонуса
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