197 research outputs found
Water related environmental issues in central asia
This article addresses the need for a sustainable water resource management in the Central Asian region with a hot, dry and continental climate. This research and its results meet sustainable development’s goals and also specifically the potential to solve or softening consequences of the Aral Sea ecological disaster. The urgency of this concern is felt most deeply in areas lacking potable water, most notably the larger Aral Sea region. During the long summer (from May until October) water consumption increases sharply and water sources cannot meet the demand. Intensive water use and sharply increasing of the water demand misbalances water flow in the main rivers as Syr Darya and Amu Darya which feed the Aral Sea. The primary challenge facing water supply and sustainability specialists in Central Asia and specifically in Uzbekistan is to balance competing water supply demand and water sources preservation in the region. Among these demands is the urgency of halting further depletion of water in the Aral Sea, and, ideally, to augment the water in that basin. But there is also the need to develop high quality water delivery systems for human and industrial use. And, of course, there is the question of what water can be left for the agricultural sector of the dry and hot temperature region to irrigate its crops or just sustainable water resources management. This study will address water-related issues in the Central Asian Republics with special emphasis on the Republic of Tajikistan. The authors analyse a current situation and describe the factors that contribute to these issues and will provide recommendations for alleviating the Aral Sea disaster. Authors offer to solve this problem with wider team from different fields
Actualization of a statement through order of the sentence (the Russian and Tajik languages)
The objective of the article is examining the words order in an utterance of the Russian and Tajik languages in comparative and typological aspects; revealing peculiarities of the structural-grammatical and actual aspects of studying the words order in sentences of the compared languages, depending whereon regular laws of rigidity or flexibility of the words order and linear-dynamic structures of a sentence in the compared languages are established, which allows to take a fresh look at the issue of interaction between the communicative and constructive structures in the languages under study (Russian and Tajik) and to determine the role of various means of expressing the words order in forming different types of information in the Russian and Tajik languages. Materials and methods: descriptive method; linguistic experiment integrating various types of transformation; comparative method revealing differences of communicative structures of reviewed sentences, verbal statements, types of words order in sentences and statements; direct observation method implying observing arrangement of words in texts when expressing the grammatical and logical base of a sentence. Tables presented in the article reflect the basic models of words order in the Russian and Tajik languages which are necessary in practical teaching of the both languages. Practical significance lies in expansion and deepening of theoretical knowledge of the role of words order and other means of actual articulation of a sentence in the Russian and Tajik languages; in formation of communicative competence and practical skills in process of professional teaching of translators and editors, and also in working-out of the general theory of words order in sentences, communicative structure of a sentence and functional grammar, which is one of leading lines of researching of the sentence in the modern linguistics. © 2018 by the authors
Effect of thermomechanical impacts on the deformation of thin polyimide films at uniaxial tension
Thermomechanical studies of the dependence of deformation on time (t) and temperature (T) for various static stresses in polyimide under uniaxial tension were carried out. Temporal deformation curves for static stresses in the range from 75 to 110 MPa consist of two stages: 1 - increase; 2 - exit to saturation, which is associated with a change in the nature of structural transformations of macromolecules, due to the action of the static stresses. An increase in temperature and voltage leads to an increase in the dependence e (Т). This is due to the intensification of the processes of structuring macromolecules with increasing temperature and are supplemented by processes of breaking bonds between macromolecules, which increase the strain rate. Experimental data are described in terms of exponential and linear models
Study of deformation dependence on time in polyethylene terephthalate for different static loads and irradiation doses
Complex experiments were conducted on deformation dependence on time for different static loads and irradiation doses in polyethylene terephthalate. Curves of time (t) dependence of deformation (?) show a significant change in the behavior of the material after irradiation. The obtained dependence curves of on t for both non-irradiated and irradiated materials are satisfactorily described by cascade-probability model
Study of the influence of the electron irradiation dose on the deformation of Mylar films taking into account the processes of destruction and crosslinking
Experimental studies of the dependence of the deformation [epsilon] on the dose of electron irradiation D taking into account the processes of destruction and crosslinking for films of the Mylar type have been carried out. It was obtained that the dependence of [epsilon] on D for the process of cross-linking is described by a linear and destruction by an exponential function
Study of the influence of the electron irradiation dose on the deformation of Mylar films taking into account the processes of destruction and crosslinking
Experimental studies of the dependence of the deformation [epsilon] on the dose of electron irradiation D taking into account the processes of destruction and crosslinking for films of the Mylar type have been carried out. It was obtained that the dependence of [epsilon] on D for the process of cross-linking is described by a linear and destruction by an exponential function
Search for pentaquark in high statistics measurement of at CLAS
The exclusive reaction was studied in the
photon energy range between 1.6-3.8 GeV searching for evidence of the exotic
baryon . The decay to requires the assignment of
strangeness to any observed resonance. Data were collected with the CLAS
detector at the Thomas Jefferson National Accelerator Facility corresponding to
an integrated luminosity of 70 . No evidence for the
pentaquark was found. Upper limits were set on the production cross section as
function of center-of-mass angle and mass. The 95% CL upper limit on the
total cross section for a narrow resonance at 1540 MeV was found to be 0.8 nb.Comment: Submitted to Physical Review Letter
Первый опыт репротезирования аортального клапана по методике «valve in valve» у пациента с дисфункцией биологического протеза
Introduction. Aortic valve replacement in cardiopulmonary bypass with suture fixation of the prosthesis is the “gold standard” in cardiac surgery. Currently, the frequency of use of heart valve bioprostheses is increasing in older patients. Despite all the advantages of using heart valve bioprostheses, this type of prosthesis has a major drawback - it is not durable. In most cases, the reason for the dysfunction of prostheses in the late postoperative period is early calcification of the prosthesis valves or their rupture due to degeneration. With the development of new “gentle” techniques for replacing heart valves, transcatheter aortic valve implantation was introduced into clinical practice. The use of transcatheter aortic valve implantation (TAVI) “valve in valve” for reoperations in older patients is of great interest, since in recent years the procedure has been widely used in clinical practice and shows promising data in patients with high surgical risk.Aim of study. Show first experience of using a technique «valve in valve» at N.V. Sklifosovsky Research Institute for Emergency Medicine.Material and methods. The results of surgical treatment of a patient with aortic valve bioprosthesis dysfunction using the TAVI “valve in valve” technique are presented.Results. The use of the TAVI “valve in valve” method made it possible to perform reprosthetics of the aortic valve (AV) from a transfemoral approach, not to increase the volume of intervention during reoperation, to avoid trauma to the structures of the heart and nearby tissues when accessing the AV in a patient with a high surgical risk.Conclusion. The use of the TAVI “valve in valve” method in cardiac surgery makes it possible to achieve good immediate and long-term results when it is necessary to replace the AV in patients with a high surgical risk.Протезирование аортального клапана в условиях искусственного кровообращения с шовной фиксацией протеза является «золотым стандартом» в кардиохирургии. В настоящее время растет частота использования биопротезов клапанов сердца у пациентов старшего возраста. Несмотря на все преимущества использования биопротезов клапана сердца, у данного типа протезов существует главный недостаток — это их недолговечность. Причиной дисфункции протезов в отдаленном послеоперационном периоде в большинстве наблюдений является ранний кальциноз створок протеза или их разрыв вследствие дегенерации. С развитием новых «щадащих» технологий по замене клапанов сердца в клиническую практику была внедрена транскатетерная имплантация аортального клапана. Использование метода транскатетерной имплантации аортального клапана (TAVI) «valve in valve» (клапан в клапан) при повторных вмешательствах у пациентов старшего возраста представляет большой интерес, так как в последние годы процедура в клинической практике широко применяется и показывает многообещающие данные у пациентов с высоким хирургическим риском.Цель. Показать первый опыт использования методики «valve in valve» в НИИ СП им. Н.В. Склифосовского.Материал И методы. Представлен результат хирургического лечения пациентки с дисфункцией биопротеза аортального клапана по методике TAVI «valve in valve».Результаты. Использование метода TAVI «valve in valve» позволило выполнить репротезирование аортального клапана (АК) из трансфеморального доступа, не увеличивать объем вмешательства при повторной операции, избежать травматизации структур сердца и близлежащих тканей при осуществлении доступа к АК у пациента с высоким хирургическим риском.Вывод. Использование в кардиохирургической практике метода TAVI «valve in valve» позволяет добиваться хороших непосредственных и отдаленных результатов при необходимости репротезирования АК у пациентов высокого хирургического риска
Light Vector Mesons in the Nuclear Medium
The light vector mesons (, , and ) were produced in
deuterium, carbon, titanium, and iron targets in a search for possible
in-medium modifications to the properties of the meson at normal nuclear
densities and zero temperature. The vector mesons were detected with the CEBAF
Large Acceptance Spectrometer (CLAS) via their decays to . The rare
leptonic decay was chosen to reduce final-state interactions. A combinatorial
background was subtracted from the invariant mass spectra using a
well-established event-mixing technique. The meson mass spectrum was
extracted after the and signals were removed in a nearly
model-independent way. Comparisons were made between the mass spectra
from the heavy targets () with the mass spectrum extracted from the
deuterium target. With respect to the -meson mass, we obtain a small
shift compatible with zero. Also, we measure widths consistent with standard
nuclear many-body effects such as collisional broadening and Fermi motion.Comment: 15 pages, 18 figures, 3 table
Measurement of Deeply Virtual Compton Scattering with a Polarized Proton Target
The longitudinal target-spin asymmetry A_UL for the exclusive
electroproduction of high energy photons was measured for the first time in
p(e,e'p\gamma). The data have been accumulated at Jefferson Lab with the CLAS
spectrometer using 5.7 GeV electrons and a longitudinally polarized NH_3
target. A significant azimuthal angular dependence was observed, resulting from
the interference of the Deeply Virtual Compton Scattering and Bethe-Heitler
processes. The amplitude of the sin(phi) moment is 0.252 +/- 0.042(stat) +/-
0.020(sys). Theoretical calculations are in good agreement with the magnitude
and the kinematic dependence of the target-spin asymmetry, which is sensitive
to the generalized parton distributions H and H-tilde.Comment: Modified text slightly, added reference
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