895 research outputs found

    A nonstationary form of the range refraction parabolic equation and its application as an artificial boundary condition for the wave equation in a waveguide

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    The time-dependent form of Tappert's range refraction parabolic equation is derived using Daletskiy-Krein formula form noncommutative analysis and proposed as an artificial boundary condition for the wave equation in a waveguide. The numerical comparison with Higdon's absorbing boundary conditions shows sufficiently good quality of the new boundary condition at low computational cost.Comment: 12 pages, 9 figure

    Three natural mechanical systems on Stiefel varieties

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    We consider integrable generalizations of the spherical pendulum system to the Stiefel variety V(n,r)=SO(n)/SO(nr)V(n,r)=SO(n)/SO(n-r) for a certain metric. For the case of V(n,2) an alternative integrable model of the pendulum is presented. We also describe a system on the Stiefel variety with a four-degree potential. The latter has invariant relations on TV(n,r)T^*V(n,r) which provide the complete integrability of the flow reduced on the oriented Grassmannian variety G+(n,r)=SO(n)/SO(r)×SO(nr)G^+(n,r)=SO(n)/SO(r)\times SO(n-r).Comment: 14 page

    Sensitivities of Low Energy Reactor Neutrino Experiments

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    The low energy part of the reactor neutrino spectra has not been experimentally measured. Its uncertainties limit the sensitivities in certain reactor neutrino experiments. The origin of these uncertainties are discussed, and the effects on measurements of neutrino interactions with electrons and nuclei are studied. Comparisons are made with existing results. In particular, the discrepancies between previous measurements with Standard Model expectations can be explained by an under-estimation of the low energy reactor neutrino spectra. To optimize the experimental sensitivities, measurements for \nuebar-e cross-sections should focus on events with large (>>1.5 MeV) recoil energy while those for neutrino magnetic moment searches should be based on events <<100 keV. The merits and attainable accuracies for neutrino-electron scattering experiments using artificial neutrino sources are discussed.Comment: 25 pages, 9 figure

    Molecular-genetic aspects of the endometrium state on the day of the tentative implantation window in women with recurrent miscarriage in the programs of assisted reproductive technologies

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    Golovatyuk K. P., Nosenko O. M., Makshayeva E. T., Trofimov D. Yu., Donnikov A. E., Kolin V. V. Molecular-genetic aspects of the endometrium state on the day of the tentative implantation window in women with recurrent miscarriage in the programs of assisted reproductive technologies. Journal of Education, Health and Sport. 2017;7(9):621-626. eISSN 2391-8306. DOI http://dx.doi.org/10.5281/zenodo.1068361 http://ojs.ukw.edu.pl/index.php/johs/article/view/5076 The journal has had 7 points in Ministry of Science and Higher Education parametric evaluation. Part B item 1223 (26.01.2017). 1223 Journal of Education, Health and Sport eISSN 2391-8306 7 © The Authors 2017; This article is published with open access at Licensee Open Journal Systems of Kazimierz Wielki University in Bydgoszcz, Poland Open Access. This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited. This is an open access article licensed under the terms of the Creative Commons Attribution Non Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted, non commercial use, distribution and reproduction in any medium, provided the work is properly cited. This is an open access article licensed under the terms of the Creative Commons Attribution Non Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted, non commercial use, distribution and reproduction in any medium, provided the work is properly cited. The authors declare that there is no conflict of interests regarding the publication of this paper. Received: 15.08.2017. Revised: 20.09.2017. Accepted: 29.09.2017. MOLECULAR-GENETIC ASPECTS OF THE ENDOMETRIUM STATE ON THE DAY OF THE tentative IMPLANTATION WINDOW IN WOMEN WITH recurrent miscarriage IN THE PROGRAMS OF ASSISTED REPRODUCTIVE TECHNOLOGIES 1K. P. Golovatyuk, 2O. M. Nosenko, 1E. T. Makshayeva, 3D. Yu. Trofimov, 4A. E. Donnikov, 3V. V. Kolin 1Limited Liability Company Medical Center for Reproductive Health "Gameta", Odessa, Ukraine; 2Odessa National Medical University, Ukraine; 3Limited Liability Company "NPF DNA-Technology", Moscow, Russia; 4FGBU Scientific Center for Obstetrics, Gynecology and Perinatology. named after acad. V.I. Kulakov Ministry of Health care and Social Development of Russia, Moscow, Russia; e-mail: [email protected] Abstract More than 50% of pregnant women after the programs of assisted reproductive technologies (ART) face the problem of recurrent miscarriage (RMC), especially in the first trimester. Significant role in the development of RMC has infectious factor and chronic inflammation in the endometrium. The aim: to reveal the peculiarities of immune response mRNA genes of the inflammatory component expression in the period of the tentative implantation window (TIW) in women with RMC in ART programs. Material and methods. The main group consisted of 240 patients with RMC in ART programs; the control group included 100 conditionally healthy fertile women. On the ground of PCR reverse transcription, the mRNA of the IL-1β, IL-2, IL-10, Foxp3, TLR9, IL-2Rα cytokine genes was examined in endometrial samples obtained with the help of biopsy on the TIW day. Results. Analysis of the transcriptional profile of the immune response genes in the endometrium on TIW day revealed that the relative level of mRNA expression of the IL-1β, IL-2, Foxp3, TLR9, IL-2Rα genes did not differ significantly in the main and control groups. Statistically significant decrease in mRNA expression of IL-10 gene was observed in women with RPL. Conclusions. A feature of mRNA expression of the inflammatory component of the immune response in TIW period in women with RMC in ART programs is a decrease in the expression level of the IL-10 gene mRNA, which may be one of the reasons for the unfavorable outcomes of the onset pregnancy. Key words: recurrent miscarriage, assisted reproductive technologies, immune response, reverse transcription-polymerase chain reaction, tentative implantation window

    Probing Low Energy Neutrino Backgrounds with Neutrino Capture on Beta Decaying Nuclei

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    We study the interaction of low energy neutrinos on nuclei that spontaneously undergo beta decay showing that the product of the cross section times neutrino velocity takes values as high as 10^{-42} cm^2 c for some specific nuclei that decay via allowed transitions. The absence of energy threshold and the value of the cross section single out these processes as a promising though very demanding approach for future experiments aimed at a direct detection of low energy neutrino backgrounds such as the cosmological relic neutrinos.Comment: Includes a discussion of local relic neutrino density effect on neutrino capture rate. Accepted for publication in JCA

    Systems of Hess-Appel'rot Type and Zhukovskii Property

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    We start with a review of a class of systems with invariant relations, so called {\it systems of Hess--Appel'rot type} that generalizes the classical Hess--Appel'rot rigid body case. The systems of Hess-Appel'rot type carry an interesting combination of both integrable and non-integrable properties. Further, following integrable line, we study partial reductions and systems having what we call the {\it Zhukovskii property}: these are Hamiltonian systems with invariant relations, such that partially reduced systems are completely integrable. We prove that the Zhukovskii property is a quite general characteristic of systems of Hess-Appel'rote type. The partial reduction neglects the most interesting and challenging part of the dynamics of the systems of Hess-Appel'rot type - the non-integrable part, some analysis of which may be seen as a reconstruction problem. We show that an integrable system, the magnetic pendulum on the oriented Grassmannian Gr+(4,2)Gr^+(4,2) has natural interpretation within Zhukovskii property and it is equivalent to a partial reduction of certain system of Hess-Appel'rot type. We perform a classical and an algebro-geometric integration of the system, as an example of an isoholomorphic system. The paper presents a lot of examples of systems of Hess-Appel'rot type, giving an additional argument in favor of further study of this class of systems.Comment: 42 page

    НАПРЯЖЕНИЕ ВОЛОЧЕНИЯ СПЛОШНЫХ ПРОФИЛЕЙ ПРЯМОУГОЛЬНОГО СЕЧЕНИЯ

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    In designing the rectangular section drawing process, it is convenient to use the analytical expressions allowing estimating at once the effect of various process factors. The use of drawing tools with optimum angles makes possible to lower the power consumption, destruction, and unsoundness of piece part. The design procedure for calculation of rectangular section drawing stresses is proposed. Formulas for calculation of drawing stress and definition of optimum angles of the drawing tool channel are derived. The optimum angles are shown to depend on friction and reduction ratio.При проектировании процесса волочения профилей прямоугольного сечения удобно использовать аналитические выражения, позволяющие оперативно оценивать влияние разных технологических факторов. Применение волочильного инструмента с оптимальными углами позволяет сократить энергозатраты, снизить разрушение и дефектность заготовки. В данной работе предлагается методика расчета напряжения волочения профиля прямоугольного сечения. Получены формулы для расчета напряжения волочения и определения оптимальных углов канала волочильного инструмента. Показано, что оптимальные углы зависят от коэффициентов трения и вытяжки

    Neutrinos in a spherical box

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    In the present paper we study some neutrino properties as they may appear in the low energy neutrinos emitted in triton decay with maximum neutrino energy of 18.6 keV. The technical challenges to this end can be achieved by building a very large TPC capable of detecting low energy recoils, down to a a few tenths of a keV, within the required low background constraints. More specifically We propose the development of a spherical gaseous TPC of about 10-m in radius and a 200 Mcurie triton source in the center of curvature. One can list a number of exciting studies, concerning fundamental physics issues, that could be made using a large volume TPC and low energy antineutrinos: 1) The oscillation length involving the small angle of the neutrino mixing matrix, directly measured in this disappearance experiment, is fully contained inside the detector. Measuring the counting rate of neutrino-electron elastic scattering as a function of the distance of the source will give a precise and unambiguous measurement of the oscillation parameters free of systematic errors. In fact first estimates show that even with a year's data taking a sensitivity of a few percent for the measurement of the above angle will be achieved. 2) The low energy detection threshold offers a unique sensitivity for the neutrino magnetic moment which is about two orders of magnitude beyond the current experimental limit. 3) Scattering at such low neutrino energies has never been studied and any departure from the expected behavior may be an indication of new physics beyond the standard model. In this work we mainly focus on the various theoretical issues involved including a precise determination of the Weinberg angle at very low momentum transfer.Comment: 16 Pages, LaTex, 7 figures, talk given at NANP 2003, Dubna, Russia, June 23, 200

    The Maslov index and nondegenerate singularities of integrable systems

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    We consider integrable Hamiltonian systems in R^{2n} with integrals of motion F = (F_1,...,F_n) in involution. Nondegenerate singularities are critical points of F where rank dF = n-1 and which have definite linear stability. The set of nondegenerate singularities is a codimension-two symplectic submanifold invariant under the flow. We show that the Maslov index of a closed curve is a sum of contributions +/- 2 from the nondegenerate singularities it is encloses, the sign depending on the local orientation and stability at the singularities. For one-freedom systems this corresponds to the well-known formula for the Poincar\'e index of a closed curve as the oriented difference between the number of elliptic and hyperbolic fixed points enclosed. We also obtain a formula for the Liapunov exponent of invariant (n-1)-dimensional tori in the nondegenerate singular set. Examples include rotationally symmetric n-freedom Hamiltonians, while an application to the periodic Toda chain is described in a companion paper.Comment: 27 pages, 1 figure; published versio

    Assessment of morphological criteria for the efficiency of radiofrequency circumferential denervation of the pulmonary artery in the experiment (animals, pigs)

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    The aim of the study. To assess the influence of radiofrequency circumferential exposure modes on the morphological parameters of the pulmonary artery tissues in animal experiment (pigs).Material and methods. In the experiments, we used outbred pigs divided into 3 groups (4 animals in each). The first experimental group included 188 histological samples of the pulmonary arteries (PA) after radiofrequency circumferential exposure on the PA using an ablator clamp. Two lines of exposure on the PA and two lines of exposure on each PA mouth were performed. Ablation was performed until the target level of tissue impedance between the ablator branches corresponding to the values at transmural damage was reached. The second experimental group included 162 histological samples of the PA after circumferential denervation of pulmonary trunk and both PA mouths. Ablation was completed upon reaching 50 % impedance level relative to the impedance values at transmural damage. The third group (control) included 55 histological samples of PA without radiofrequency exposure. The material obtained was studied using light microscopy, hematoxylin and eosin and van Gieson’s staining, and also by impregnation with silver salts according to S. Ramón y Cajal.Conclusions. Morphological criteria for irreversible destruction of nerve fibers and ganglia of the pulmonary trunk adventitial layer and for PA bifurcation were obtained when using two studied ablation modes. Circumferential PA denervation using subthreshold power of radiofrequency exposure made it possible to avoid irreversible damage to the nerve endings and ganglia of the PA intimal layer and thus to preserve physiological neuroreflectory regulation of the PA and the entire pulmonary circulation. Turning off the cascade of pathological reflexes eliminates the factor of the progression of pulmonary hypertension associated with an increase in peripheral resistance of the pulmonary arterioles precapillary link
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