90 research outputs found
Mesofauna influence on hamification process of vegetable oddments with partticipation microarthropod
Relevance of the studied problem is caused by the fact that stability of natural ecosystems strongly depends on functioning of their destructive block which closes a biological circulation. The organisms that ensure functioning of the destructive block are very different and numerous. All of them partly supplement, partly duplicate functions of each other that is an important factor of reliability of this ecosystem block. Shallow arthropods are important regulators of fossils mineralization and immobilizations of various biogens. Experiments demonstrate that if there are microarthropods, humification processes amplify and the optical density of humic acids raises. The aim of the article is to show degree and depth of change of mineralization and humification processes at the interaction of microarthropods and some mesofauna representatives in the processes of transformation of organic substance of vegetable oddments on the basis of experimental research. The most popular method to a research of this problem is the creation of laboratory microecosystems which have a clear boundary, which are easily reproduced and convenient for experimenting with subsequent instrumental determination of quantitative and qualitative humification parameters. In the course of experimental work it is revealed that the activity of soil-forming invertebrates results in strengthening humification processes. Humification rates, transformation depth of organic substance directly depend on cenotic organization of destructors. It is obvious that, the more complete the composition of biodegradative agents, the more intensive the decomposition process, the stronger the humification processes prevail over mineralization, the higher their maturity degree. All above-mentioned has a huge value to preserve a long-term fertility and high agronomical soil value, both in agrophitocenosis, and in natural biogeocenosis. © 2016 Simono, Svetkina and Kryuchkov
Model of preparation of a craftsman in the framework of continuous vocational education
The significance of the issue under study is stipulated by a social order for targeted preparation of stafffor a craft type of companies. The aim of the article is development and approbation of structural-functional model of continuous craftsman education. The main research method of the given issue is modeling which enables to see the issue as a process of targeted, continuous and conscious acquiring of vocational competences by future craftsmen, in the course of formal, non-formal and informal education. The article presents a structural-functional model of continuous craftsman education that includes formal, non-formal and informal education and outlines a complex of organizational-pedagogical conditions contributing to implementation of this model. The contents of the article might be of interest for students of craft trades, all categories of vocational-pedagogical workers, specialists of state government institutions in the area of vocational education. © Authors
The Minimum-Uncertainty Squeezed States for for Atoms and Photons in a Cavity
We describe a six-parameter family of the minimum-uncertainty squeezed states
for the harmonic oscillator in nonrelativistic quantum mechanics. They are
derived by the action of corresponding maximal kinematical invariance group on
the standard ground state solution. We show that the product of the variances
attains the required minimum value 1/4 only at the instances that one variance
is a minimum and the other is a maximum, when the squeezing of one of the
variances occurs. The generalized coherent states are explicitly constructed
and their Wigner function is studied. The overlap coefficients between the
squeezed, or generalized harmonic, and the Fock states are explicitly evaluated
in terms of hypergeometric functions. The corresponding photons statistics are
discussed and some applications to quantum optics, cavity quantum
electrodynamics, and superfocusing in channeling scattering are mentioned.
Explicit solutions of the Heisenberg equations for radiation field operators
with squeezing are found.Comment: 27 pages, no figures, 174 references J. Phys. B: At. Mol. Opt. Phys.,
Special Issue celebrating the 20th anniversary of quantum state engineering
(R. Blatt, A. Lvovsky, and G. Milburn, Guest Editors), May 201
A transverse current rectification in graphene superlattice
A model for energy spectrum of superlattice on the base of graphene placed on
the striped dielectric substrate is proposed. A direct current component which
appears in that structure perpendicularly to pulling electric field under the
influence of elliptically polarized electromagnetic wave was derived. A
transverse current density dependence on pulling field magnitude and on
magnitude of component of elliptically polarized wave directed along the axis
of a superlattice is analyzed.Comment: 12 pages, 6 figure
Hospital Stage of Myocardial Infarction Treatment in 13 Regions of Russian Federation by Results of the International Research
Aim. To describe the characteristics of the patient with MI who is admitted to a hospital and to characterize the main diagnostic and treatment interventions in clinic. Material and methods. This study is observational and the part of big international project. It includes a representative sample of patients with MI admitted to 16 clinics in 13 regions of Russian Federation (Arkhangelsk region, Belgorod region, Bryansk region, Tver region, Saratov region, Rostov region, Samara region, the Republic of Tatarstan, Perm region, Tyumen region, Khanty-Mansiysk Autonomous district, Kemerovo region, Altai region). Patients were selected at random from among those experiencing a MI that were alive on the next morning after hospitalization. Enrollment took place from June 2015 to August 2016. Results. Of 1,128 patients included in the study, 872 were male (77.3%) and 256 females. 21.4% of patients had a previous MI, 8.3% had undergone PCI, and 2.2% CABG. Turning to cardiovascular risk factors, 46.2% of patients smoked prior to hospitalization, 34.6% were obese and 52.1% had a high cholesterol level. Only 40.0% of patients had no contact with the health care system within 12 months before the MI. Every fourth patient (25.1%) had undergone dispensarisation within 12 months before MI, women significantly often than men (33.5% and 22.6%, p < 0.001). Initial revascularization was performed in 73.2% of patients, PCI was the initial revascularization attempt in 49.4% of patients, and PCI with stenting in 46.7%. Conclusion. Patient with a MI in Russian clinics is likely to have had a history of cardiovascular disease, and to have regular contact with the health care system within 12 months before the development of cardiovascular event. We demonstrated the high rates of appropriate MI treatment, without significant gender and age difference (except for thrombolysis), however, there is a reserve for increasing the proportion of patients who are undergoing revascularization
Fluorescence spectrum of a two-level atom driven by a multiple modulated field
We investigate the fluorescence spectrum of a two-level atom driven by a multiple amplitude-modulated field. The driving held is modeled as a polychromatic field composed of a strong central (resonant) component and a large number of symmetrically detuned sideband fields displaced from the central component by integer multiples of a constant detuning. Spectra obtained here differ qualitatively from those observed for a single pair of modulating fields [B. Blind, P.R. Fontana, and P. Thomann, J. Phys. B 13, 2717 (1980)]. In the case of a small number of the modulating fields, a multipeaked spectrum is obtained with the spectral features located at fixed frequencies that are independent of the number of modulating fields and their Rabi frequencies. As the number of the modulating fields increases, the spectrum ultimately evolves to the well-known Mellow triplet with the sidebands shifted from the central component by an effective Rabi frequency whose magnitude depends on the initial relative phases of the components of the driving held. For equal relative phases, the effective Rabi frequency of the driving field can be reduced to zero resulting in the disappearance of fluorescence spectrum, i.e., the atom can stop interacting with the field. When the central component and the modulating fields are 180 degrees out of phase, the spectrum retains its triplet structure with the sidebands located at frequencies equal to the sum of the Rabi frequencies of the component of the driving field. Moreover, we shaw that the frequency of spontaneous emission can be controlled and switched from one frequency to another when the Rabi frequency or initial phase of the modulating fields are varied
Воздействие высокой концентрации оксида азота на оксигенаторы аппаратов искусственного кровообращения (экспериментальное исследование)
The aim of the study. To study the effect of high nitric oxide concentrations on hollow polypropylene fibers of oxygenators.Materials and methods. The study was conducted in two stages. At the first stage, we evaluated the stability of oxygenator membrane made of hollow polypropylene fibers after six hours of exposure to air-oxygen mixture containing NO at 500 parts per million, or 500 pro pro mille (ppm) concentration, using mass spectrometry and infrared spectroscopy. At the second stage, an experiment with cardiopulmonary bypass (CPB) was conducted on 10 pigs. In the study group (n=5) animals sweep gas was supplied to the oxygenator as an air-oxygen mixture with NO at 100 ppm. In the control group animals (n=5) an air-oxygen mixture was used without NO. The CPB lasted for 4 hours, followed by observation for 12 hours. NO, NO2 (at the inlet and outlet of the oxygenator), and the dynamics of methemoglobin were evaluated. After weaning of animals from CPB, the oxygenators were tested for leakproofness, and scanning electron microscopy (SEM) was performed.Results. The oxygenator made of polypropylene hollow fibers retained its gas transfer parameters after six hours of exposure to air-oxygen mixture containing NO at 500 ppm. Based on IR-Fourier spectroscopy findings, NO did not affect structural integrity of polypropylene membranes. NO added to gas mixture at 100 ppm did not increase NO2 to toxic level of 2 ppm in 91% of control tests during 4 hours CPB in pigs; mean value was 1.58 ± 0.28 ppm. Methemoglobin concentration did not exceed the upper limit of permissible level (3%), and there were no statistically significant differences with the control group. All tested oxygenators have passed the leakproofness test. According to SEM findings, larger amounts of fibrin deposits were found in the control group oxygenators vs study group.Conclusion. There were no negative effects of NO at 500 ppm concentration on the oxygenator membrane made of hollow polypropylene fibers. NO at 100 ppm in a gas-mixture supplied to oxygenators did not lead to an exceedance of safe NO2 and methemoglobin concentrations in an animal model. Reduced fibrin deposits on hollow fibers of polypropylene oxygenator membranes were observed when with NO at a level of 100 ppm was added to a gas mixture. Цель исследования. Изучить воздействие высоких концентраций оксида азота на полипропиленовые полые волокна оксигенаторов.Материалы и методы. Исследование провели в два этапа. На первом этапе с помощью масс-спектрометрии и инфракрасной спектроскопии выполнили оценку стабильности мембраны оксигенатора из полых волокон полипропилена после шестичасового воздействия воздушно-кислородной смеси, содержащей NO в концентрации 500 пропромилле, или 500 частей на миллион – parts per million (ppm). На втором этапе провели эксперимент на 10 свиньях с подключением аппарата искусственного кровообращения (ИК). Животным основной группы (n=5) в оксигенатор подавали воздушно-кислородную смесь, содержащую NO в концентрации 100 ppm. Животным контрольной группы (n=5) в оксигенатор подавали воздушно-кислородную смесь без NO. Процедура ИК длилась 4 часа, затем следовало наблюдение в течение 12 часов. Оценивали NO, NO2 (на входе и выходе из оксигенатора), динамику метгемоглобина. После отключения от ИК оксигенаторы тестировали на герметичность, а также выполняли сканирующую электронную микроскопию (СЭМ).Результаты. Оксигенатор из полипропиленовых полых волокон сохранял свои газотранспортные характеристики после шестичасового воздействия воздушно-кислородной смеси с добавлением NO в концентрации 500 ppm. По данным ИК-Фурье спектроскопии показали, что NO не влияет на структуру мембран из полипропилена. Добавление NO в дозировке 100 ppm во время 4 часов ИК у свиней не сопровождалось повышением концентрации NO2 до токсичного уровня 2 ppm в 91% измерений: среднее значение составило 1,58 ± 0,28 ppm. Концентрация метгемоглобина не превышала верхнего предела допустимых значений (3%), не обнаружили каких-либо статистически значимых различий при сравнении с группой контроля. Все исследуемые оксигенаторы выдержали тестирование на герметичность. По результатам СЭМ оксигенаторы группы контроля характеризовались большим количеством отложений фибрина, чем оксигенаторы основной группы.Заключение. Негативного воздействия NO в концентрации 500 ppm на мембраны оксигенаторов из полых волокон полипропилена не обнаружили. Подача в оксигенатор NO в концентрации 100 ppm NO2 не приводила к превышению безопасного содержания NO2 и метгемоглобина в эксперименте на животных. Выявили снижение образования отложений фибрина на полых волокнах мембран оксигенаторов из полипропилена при подаче NO в концентрации 100 ppm
A dominant acoustic-gravity mode in the polar thermosphere
The article presents a summary of the main findings of the systematic study of
acoustic-gravity waves (AGWs) in the polar thermosphere. This study was based on
the in situ measurements made by the Dynamics Explorer 2 (DE2)
spacecraft late in its mission when it descended low enough
(250–400 km). It was found out that AGWs in the polar thermosphere are observed within a
narrow frequency band close to the Brunt–Väisälä frequency and with
horizontal wavelengths about 500–600 km. The broadband spectrum of
travelling ionospheric disturbance (TID) frequencies observed by radars is caused by the Doppler effect. The AGW
amplitudes do not depend on the altitude, but grow almost linearly with the
wind velocity. They propagate towards the wind
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