244 research outputs found

    A view on the problems of Quantum Gravity

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    The existing approaches to quantization of gravity aim at giving quantum description of 3-geometry following to the ideas of the Wheeler -- DeWitt geometrodynamics. In this description the role of gauge gravitational degrees of freedom is missed. A probable alternative is to consider gravitational dynamics in extended phase space, taking into account the distinctions between General Relativity and other field theories. The formulation in extended phase space leads to some consequences at classical and quantum levels. At the classical level, it ensures that Hamiltonian dynamics is fully equivalent to Lagrangian dynamics, and the algebra of Poisson brackets is invariant under reparametrizations in a wide enough class including reparametrizations of gauge variables, meantime in the canonical Dirac approach the constraints' algebra is not invariant that creates problems with quantization. At the quantum level, the approach come to the description in which the observer can see various but complementary quantum gravitational phenomena in different reference frames that answers the spirit of General Relativity and Quantum Theory. Though until now the approach was applied to General Relativity in its original formulations, its implementation in different trends, including Quantum Loop Gravity or some other representations of gravitational variables, would also be of interest.Comment: 6 pages, talk presented at the International Conference on Quantum Gravity "Loops 11", Madrid, May 201

    The exact cosmological solution to the dynamical equations for the Bianchi IX model

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    Quantum geometrodynamics in extended phase space describes phenomenologically the integrated system ``a physical object + observation means (a gravitational vacuum condensate)''. The central place in this version of QGD belongs to the Schrodinger equation for a wave function of the Universe. An exact solution to the ``conditionally-classical'' set of equations in extended phase space for the Bianchi-IX model and the appropriate solution to the Schrodinger equation are considered. The physical adequacy of the obtained solutions to existing concepts about possible cosmological scenarios is demonstrated. The gravitational vacuum condensate is shown to be a cosmological evolution factor.Comment: LaTeX, 14 pages, to be published in Int. J. Mod. Phys.

    Possibilities of Autologous Fecal Microbiota Transplantation in patients with obesity and diabetes mellitus

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    Obesity and type 2 diabetes mellitus (T2DM) are major problems for public health all over the world. According to retrospective research, the prevalence of obesity has doubled in more than 70 countries since 1980, as well as the prevalence of obesity complications (atherosclerotic cardiovascular diseases, nonalcoholic fatty liver disease and their complications. There are many drug therapies for T2DM, but it is difficult to achieve a stable, clinically relevant effect on a long-term basis. The fact that a patient has both conditions makes it difficult to optimize carbohydrate metabolism and to achieve normal body weight. Many antidiabetic drugs cause weight again, which, in turn, contributes to the growth of insulin resistance (IR) and requires further intensification of therapy.In the last few years, there is a growing evidence of the relationship between the gut microbiota (GM), obesity and T2DM. There has been a steady growth of interest in such medical technology as fecal microbiota transplantation (FMT) in the world. Since there is data on the association of the gut microbiota (GM) with the development of IR and T2DM, the possibility of FMT can potentially be one of the new methods of treatment. This review presents the current state of the problem and discusses the possibility of modifying GM as a therapeutic strategy in obesity and T2DM with an accent on autologous fecal microbiota transplantation

    Type 2 diabetes and prediabetes prevalence in patients with different risk factor combinations in the NATION study

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    BACKGROUND: Type 2 diabetes (T2D) is multifactorial disease. NATION epidemiological study may provide the information about the prevalence of T2D and prediabetic state in patients with different risk factor combinations in Russian population. AIMS: To evaluate the prevalence of T2D and prediabetic state in NATION cohort depending on the amount of diabetes risk factors. MATERIALS AND METHODS: NATION is an epidemiological, cross-sectional study, designed to assess the prevalence of T2D in Russian adult population, where HbA1c was used to establish T2D (HbAc≥6,5%) and prediabetes (5,7%≤HbA1c<6,5%). Patients with T2D were either previously diagnosed or newly diagnosed. Current study presents an additional analysis of NATION cohort focused on the prevalence of T2D and prediabetic state among patients with different risk factor combinations. RESULTS: T2D and prediabetic state prevalence gradually increased among patients with following risk factors (prevalence of T2D and prediabetes respectively): low physical activity (4,3%, 18,3%), rare fruit and vegetable consumption (4,8%, 18,7%), T2D family history (7,7%, 20,3%), age ≥45 years (9,5%, 31,3%), obesity grade 1 (9,6%, 30,3%), obesity grade 2 (14,6%, 37,8%), obesity grade 3 (20,1%, 39,7%), hypertension (14,7%, 38,2%), history of diabetes during pregnancy (14,1%, 24,7%). Prevalence of T2D with single and multiple risk factors was compared to the prevalence of T2D in young patients (<45 years) without additional diabetes risk factors. Age ≥45 years was associated with 7-fold increase in T2D prevalence; obesity – 8,8-fold; family history – 5,7-fold; hypertension – 10,8-fold (p<0,001 for comparisons of every group with patients <45 years of age without other risk factors). When one patient had several risk factors combined, the prevalence of T2D increased progressively: combination of age ≥45 years and family history led to 10,7-fold rise; combination of age ≥45 years and BMI≥30kg/m2 – 11,2-fold; combination of age ≥45 years, family history and BMI≥30kg/m2 – 15,3-fold; combination of age ≥45 years, family history, BMI≥30kg/m2 and hypertension – 19,1-fold (p<0,001 for comparisons of every group with patients <45 years of age without other risk factors). CONCLUSIONS: Presence of multiple risk factors, such as age ≥45 years, obesity and hypertension led to progressive increase in the prevalence of T2D and prediabetic state. These data are important to identify patients at the highest risk of T2D among Russian population

    Feasibility and challenges of performing magnetoencephalography experiments in children with arthrogryposis multiplex congenita

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    Arthrogryposis multiplex congenita (AMC) has recently drawn substantial attention from researchers and clinicians. New effective surgical and physiotherapeutic methods have been developed to improve the quality of life of patients with AMC. While it is clear that all these interventions should strongly rely on the plastic reorganization of the central nervous system, almost no studies have investigated this topic. The present study demonstrates the feasibility of using magnetoencephalography (MEG) to investigate brain activity in young AMC patients. We also outlined the general challenges and limitations of electrophysiological investigations on patients with arthrogryposis. We conducted MEG recordings using a 306-channel Elekta Neuromag VectorView system during a cued motor task performance in four patients with arthrogryposis, five normally developed children, and five control adults. Following the voice command of the experimenter, each subject was asked to bring their hand toward their mouth to imitate the self-feeding process. Two patients had latissimus dorsi transferred to the biceps brachii position, one patient had a pectoralis major transferred to the biceps brachii position, and one patient had no elbow flexion restoration surgery before the MEG investigation. Three patients who had undergone autotransplantation prior to the MEG investigation demonstrated activation in the sensorimotor area contralateral to the elbow flexion movement similar to the healthy controls. One patient who was recorded before the surgery demonstrated subjectively weak distributed bilateral activation during both left and right elbow flexion. Visual inspection of MEG data suggested that neural activity associated with motor performance was less pronounced and more widely distributed across the cortical areas of patients than of healthy control subjects. In general, our results could serve as a proof of principle in terms of the application of MEG in studies on cortical activity in patients with AMC. Reported trends might be consistent with the idea that prolonged motor deficits are associated with more difficult neuronal recruitment and the spatial heterogeneity of neuronal sources, most likely reflecting compensatory neuronal mechanisms. On the practical side, MEG could be a valuable technique for investigating the neurodynamics of patients with AMC as a function of postoperative abilitation

    Flexible management in industry as a factor of region’s sustainable development

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    This article discusses the development of flexible management technologies in industry in current conditions. The main goal of the research is to study the features of functioning and develop a mechanism for the development of flexible technologies for managing industrial enterprises in Russia as one of the factors for the sustainable development of regions. Taking into account the goal set, the main tasks have been defined. It consists of studying the structure, a number of industrial enterprises by sectors, districts and the Russian Federation’s constituent entities; allocation of the varieties of flexible management technologies; development of a conceptual scheme and stages of the process of forming tools for the development mechanism of industrial enterprises based on flexible management technologies. The study used modern methods of collecting and statistical processing of initial information, in particular, the method of analytical groupings, the method of classifications and typologies, methods of economic, situational and system analysis. The paper deals with issues related to the analysis of the industrial production indices dynamics by entities of the Russian Federation. The problems are identified, the mechanism and stages of development of industrial enterprises have been formed on the basis of flexible management technologies. The main provisions and conclusions reflect the significance of the research and can be used by industrial enterprises in activities aimed at their development in the conditions of economic transformation. The authors’ recommendations will help to increase the competitiveness of enterprises, their sustainable functioning and development in the regions

    Ecotourism as a form of sustainable development

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    The article discusses the specificity and current trends of ecological tourism in the context of sustainable development. The authors performed a literary review of the concept of “sustainable development”, grouped the views of various authors on the definition of this concept. The modern normative-legal base of the Russian Federation in the field of steady development is analysed, the list of operating statutory acts in this sphere is revealed. The world practice of tourism development has been studied. The basic principles regulating natural ecological tourism are revealed, plans of strategic development at various levels of management are studied. The authors concluded that the current high tourism potential of the Russian Federation is underused. Ecological tourism can become one of the effective means of nature protection and formation of ecological culture

    General Relativity as Classical Limit of Evolutionary Quantum Gravity

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    We analyze the dynamics of the gravitational field when the covariance is restricted to a synchronous gauge. In the spirit of the Noether theorem, we determine the conservation law associated to the Lagrangian invariance and we outline that a non-vanishing behavior of the Hamiltonian comes out. We then interpret such resulting non-zero ``energy'' of the gravitational field in terms of a dust fluid. This new matter contribution is co-moving to the slicing and it accounts for the ``materialization'' of a synchronous reference from the corresponding gauge condition. Further, we analyze the quantum dynamics of a generic inhomogeneous Universe as described by this evolutionary scheme, asymptotically to the singularity. We show how the phenomenology of such a model overlaps the corresponding Wheeler-DeWitt picture. Finally, we study the possibility of a Schr\"odinger dynamics of the gravitational field as a consequence of the correspondence inferred between the ensemble dynamics of stochastic systems and the WKB limit of their quantum evolution. We demonstrate that the time dependence of the ensemble distribution is associated with the first order correction in â„Ź\hbar to the WKB expansion of the energy spectrum.Comment: 23 pages, to appear on Class. Quant. Gra

    Effect of triazavirine on the outcome of a lethal influenza infection and secondary bacterial pneumonia following influenza in mice

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    Pneumonia often occurs as secondary infection post influenza disease and accounts for a large proportion of the morbidity and mortality associated with seasonal and pandemic influenza outbreaks. The antiviral drug triazavirine is licensed in Russia for the treatment and prophylaxis of acute respiratory infections, including influenza A and B viruses. In the present study, we investigated the efficacy of triazavirine in a mouse model of secondary Staphylococcus aureus pneumonia following A/California/04/2009 (H1N1)pdm09 influenza virus infection. We also performed a study of the efficacy of triazavirine against the A/California/04/2009 (H1N1)pdm09 lethal influenza infection in mice. In this model, triazavirine at the dose of 25 mg/kg/day significantly enhanced the survival of animals (60% compared to 20%) and the mean survival time to death, prevented weight loss, and reduced viral titer in the lungs of mice infected with influenza virus. At doses of 50 and 100 mg/kg/day, triazavirine was highly effective in the treatment of the secondary bacterial pneumonia following influenza infection in mice. At these doses, triazavirine protected 67-75% of animals against death, increased the mean survival time to death by twofold, and reduced the virus titer by 2.2-3.0 log10TCID50/ml compared to the mice in the control group. These findings suggest the possible benefit of triazavirine treatment in reducing post influenza pneumonia incidence in humans.Pneumonia often occurs as secondary infection post influenza disease and accounts for a large proportion of the morbidity and mortality associated with seasonal and pandemic influenza outbreaks. The antiviral drug triazavirine is licensed in Russia for the treatment and prophylaxis of acute respiratory infections, including influenza A and B viruses. In the present study, we investigated the efficacy of triazavirine in a mouse model of secondary Staphylococcus aureus pneumonia following A/California/04/2009 (H1N1)pdm09 influenza virus infection. We also performed a study of the efficacy of triazavirine against the A/California/04/2009 (H1N1)pdm09 lethal influenza infection in mice. In this model, triazavirine at the dose of 25 mg/kg/day significantly enhanced the survival of animals (60% compared to 20%) and the mean survival time to death, prevented weight loss, and reduced viral titer in the lungs of mice infected with influenza virus. At doses of 50 and 100 mg/kg/day, triazavirine was highly effective in the treatment of the secondary bacterial pneumonia following influenza infection in mice. At these doses, triazavirine protected 67-75% of animals against death, increased the mean survival time to death by twofold, and reduced the virus titer by 2.2-3.0 log10TCID50/ml compared to the mice in the control group. These findings suggest the possible benefit of triazavirine treatment in reducing post influenza pneumonia incidence in humans

    Clinical Analysis of Late Age Somatoform Algic Disorder Case Following with Pain in Maxillofacial Area: Example of Dental Treatment Groundlessness

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    Case of somatoform algic disorder with pain in maxillofacial region is described on a 58 years old patient. The patient have been observed by different specialists and underwent numerous medical examinations which led as a result to groundless medical manipulations such as several teeth extirpation, removal of previously mounted metalloceramic constructions.Latest observations show that there is a link between age and pain localization rate at mouth area as well as changes in hypochondriac experience to the increase of supervaluable generations. Thus condition described becomes a disorder which is hard to diagnose and a social problem concerning early diagnostics and treatment. With time and increase of life expectancy as well as increase of assortment and affordability of dental procedures problem of somatoform algic disorder diagnostics in late age becomes more urgent. Clinical case illustrates accumulated practical experience of late age somatoform disorders treatment by combinations of antidepressants and small doses of antipsychotics. Ethiopathogenesis of this condition assessed as nociceptive, neuropathologic and then as psychogenic pain is still to be investigated. Late diagnostics in this case points to a necessity of multidisciplinary approach to such patients’ treatment in order to develop criteria to apply in practice for diagnostic mechanisms optimization and pharmacologic effect on early disorder stages
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