41 research outputs found

    Ducks on the torus: existence and uniqueness

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    We show that there exist generic slow-fast systems with only one (time-scaling) parameter on the two-torus, which have canard cycles for arbitrary small values of this parameter. This is in drastic contrast with the planar case, where canards usually occur in two-parametric families. Here we treat systems with a convex slow curve. In this case there is a set of parameter values accumulating to zero for which the system has exactly one attracting and one repelling canard cycle. The basin of the attracting cycle is almost the whole torus.Comment: To appear in Journal of Dynamical and Control Systems, presumably Vol. 16 (2010), No. 2; The final publication is available at www.springerlink.co

    Antibiotic delivery in treating acute purulent pyelonephritis in experimental animals

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    The article presents the results of treatment of acute purulent pyelonephritis simulated method of transport antibiotics. The aim of this work: an experimental rationale for the effectiveness of directed transport of antibiotics in acute purulent pyelonephritis in animals. The article presents a study of antibiotic concentrations in plasma and kidney tissues under different methods of antibiotics. The author gives morphological rationale for the use of techniques aimed at transport antibiotics modeled acute purulent pyelonephritis. The study found that when introducing cefotaxim method of transport of its concentration in renal tissue above and in the blood plasma of more constant than the traditional intravenous antibiotics. Implementation of the antibacterial therapy method of transport in the treatment of acute purulent pyelonephritis contributes to an earlier normalization of peripheral blood and accelerated the rate of reparative processes.В статье приводятся результаты лечения моделированного острого гнойного пиелонефрита методом направленного транспорта антибиотиков. Цель работы: экспериментальное обоснование эффективности направленного транспорта антибиотиков при остром гнойном пиелонефрите у животных. В статье представлены исследования концентрации антибиотика в плазме крови и ткани почки при различных методах введения антибиотиков. Авторы приводят морфологическое обоснование применения методики направленного транспорта антибиотиков при моделированном остром гнойном пиелонефрите. В ходе исследования было установлено, что при введении цефотаксима методом направленного транспорта его концентрация в почечной ткани выше, чем при традиционном внутривенном введении антибиотика, а в плазме крови более постоянна. Проведение антибактериальной терапии методом направленного транспорта в лечении острого гнойного пиелонефрита способствует более ранней нормализации показателей периферической крови и ускорению темпов репаративных процессов

    THE ASSOCIATION OF IMMUNE RESPONSE TO XENOAND ENDOBIOTIKS AND THEIRS BIOTRANSFORMATION ENZYME GENE POLYMORPHISM WITH CONGENITAL MALFORMATIONS OF THE FETUS

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    The correlation between immune response to benzo(a)pyrene and progesterone in combination with detoxification enzyme gene polymorphism (CYPIA2*1F and GSTTI) and the occurrence of congenital malformations of the fetus was revealed. It is shown that at high ratio of IgA-antibodies to benzo(a)pyrene and to progesterone in conjunction with the mutant allele of the gene CYPIA2*1F and the deletion genotype of the gene GSTTI chance of the reproductive pathology developing increases to 41 times

    МЕЗОПРОТЕРОЗОЙСКИЙ БАЗИТОВЫЙ МАГМАТИЗМ БАШКИРСКОГО МЕГАНТИКЛИНОРИЯ (ЮЖНЫЙ УРАЛ): ВОЗРАСТНЫЕ ОГРАНИЧЕНИЯ, ПЕТРОЛОГИЧЕСКИЕ И ГЕОХИМИЧЕСКИЕ ОСОБЕННОСТИ

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    Among the Riphean–Vendian dyke complexes of the basic composition, which intersect the Precambrian strata of the Bashkirian meganticlinorium (Southern Urals), one of the most common is the Kurgas gabbro-dolerite complex dated to the Early – Middle Riphean. This article presents the isotopic dating, petrological and geochemical features of the rocks belonging to the Kurgas complex. It gives the first description of the regional geochemical zoning that is reflected in a decrease in SiO2 contents from the north to the south along the Bashkirian meganticlinorium, and an increase in MgO contents in the same direction, which is attributed by the authors to an increase in the permeability of the crust to the south during opening of the Mashak riftogenic structure.New data on isotopic ages were obtained for the dyke that cuts the Satka formation of the Lower Riphean – 1318±10 (40Ar/39Ar), the intrusion in the exocontact zone of the Berdyaush rapakivi granite massif – 1349±11 Ma (U-Pb), and the andesite dyke among the metamorphic rocks of the Taratash complex – 1365.6±6.6 Ma (U-Pb). These ages, in combination with the previously obtained data, suggest that the complex formed during a rather long period of time (from 1385 to 1318 Ma, as a minimum), which corresponds to the beginning of the Middle Riphean. Isotopic U-Pb age of the dyke that cuts the contact zone of the Berdyaush massif, suggests that the major portion of the massif had already crystallized by that time and was exhumed into the shallow zone of brittle deformation.Среди рифейско-вендских дайковых комплексов основного состава, секущих докембрийские толщи Башкирского мегантиклинория (Южный Урал), одним из самых распространенных является кургасский габбро-долеритовый раннесреднерифейский комплекс. В работе собраны и обобщены данные по изотопным датировкам, петрологическим и геохимическим особенностям пород кургасского комплекса. Впервые показано наличие региональной геохимической зональности в породах комплекса, которая выражена в уменьшении содержаний SiO2 с севера на юг вдоль Башкирского мегантиклинория и увеличении содержаний MgO в этом направлении, что авторами связывается с увеличением проницаемости коры к югу при раскрытии Машакской рифтогенной структуры.Получены новые изотопные датировки для дайки, секущей саткинскую свиту нижнего рифея, – 1318±10 (40Ar/39Ar), тела в зоне экзоконтакта Бердяушского массива гранитов рапакиви – 1349±11 млн лет (U-Pb) и для дайки андезитов среди метаморфитов тараташского комплекса – 1365.6±6.6 млн лет (U-Pb). Эти данные, в сочетании с полученными ранее, указывают на формирование комплекса на достаточно большом протяжении времени – как минимум от 1385 до 1318 млн лет, что отвечает началу среднего рифея. Полученный возраст для дайки, секущей контактовую зону Бердяушского массива, позволяет предполагать, что к этому моменту массив уже в значительной мере кристаллизовался и вышел в условия хрупкой деформации

    LACEwING: A New Moving Group Analysis Code

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    Modern problems of geochemical and U-Pb geochronological studies of zircon in oceanic rocks

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    We present results of zircon LA-ICP-MS U–Pb, Lu–Hf, and trace-element study in combination with whole-rock Sm-Nd and Rb-Sr isotope data on the magmatic rocks of the Markov Deep and Ashadze hydrothermal field (Mid-Atlantic Ridge). Zircon from three gabbronorite samples in the Markov Deep defined an U–Pb ages between 0.90 ± 0.02 and 2.00 ± 0.05 Ma, with the youngest age found in the deepest sample. Zircons from four samples of gabbros and trondhjemites of the Ashadze Field have identical ages: from 1.04 ± 0.07 to 1.12 ± 0.09 Ma. Plagioclase troctolite from the Markov Deep (sample I-1069/19) contains exotic zircon grains with ages widely ranging from 90 Ma to 3.2 Ga, which is inconsistent with age of the rocks in the Mid-Atlantic Ridge. Several hypotheses are discussed to explain the origin of such exotic grains, in particular, their formation at mantle depths, or reaching these depths with subducted crust, and others. Experimental study of zirconium solubility shows that the mafic and ultramafic melts could be oversaturated with respect to zirconium only at unrealistically high contents, which usually do not occur in the corresponding rocks. Entrapped xenogenic zircon must be dissolved in the mafic and ultramafic melts and its finds in these rocks presumably indicate its disequilibrium precipitation. Zircon could be formed in the intrusive mafic rocks at the final stages of fractional crystallization, which explains the presence of own zircon in gabbroids. Zircon is very stable in crustal magmatic processes, especially at lowered activity of alkalis, but almost instantly (on geological scale) loses radiogenic lead by diffusion way under upper mantle conditions (1300–1500°C). While applying REE distribution for interpreting zircon origin, as many as possible elements should be analyzed to discriminate between intrinsic zircon element distribution and anomalies caused by defects in its structure.27 page(s

    Geochemical nature and age of the plagiogranite-gabbronorite association of the oceanic core complex of the Mid-Atlantic ridge at 5 degrees 10 ' S

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    Our newly obtained data on the geochemistry and age of plagiogranite-gabbronorite association in the oceanic core complex of the Mid-Atlantic Ridge (MAR) at 5A degrees 10'S suggest close genetic relations between these rocks in this segment of the ridge. The U/Pb zircon age of an oceanic plagiogranite (OPG) sample is 1.059 +/- 0.055 Ma and is in good agreement with the zircon age of plutonic rocks in the oceanic core complex of northern MAR. A distinctive geochemical feature of the rocks is their unusually depleted Sr-87/Sr-86 and Nd-143/Nd-144 ratios, which suggest that the plutonic rocks of the gabbronorite-plagiogranite association in MAR at 5A degrees 10'S could be derived from the most strongly depleted mantle reservoir of all known to occur beneath the axial MAR zone. The COMAGMAT-5.2 numerical thermodynamic simulation of the possible crystallization links between the plagiogranite and gabbronorite from the MAR segment at 5A degrees 10'S led us to conclude that the leading role in the origin of the plagiogranite was played by a two-stage process: the partial melting of the gabbronorite and the subsequent fractionation of the newly generated melt. The regional differences between the isotopic-geochemical parameters of MAR plagiogranites can, perhaps, reflect local specifics of so-called hydrothermal anatexis, such as the geochemical features of the rocks involved in this process and the parameters of the hydrothermal process, for example, variations in the W/R ratio

    MEZOPROTEROZOIC BASITE MAGMATISM OF THE BASHKIRIAN MEGANTICLINORIUM (SOUTHERN URALS): AGE CONSTRAINTS, PETROLOGICAL AND GEOCHEMICAL FEATURES

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    Among the Riphean–Vendian dyke complexes of the basic composition, which intersect the Precambrian strata of the Bashkirian meganticlinorium (Southern Urals), one of the most common is the Kurgas gabbro-dolerite complex dated to the Early – Middle Riphean. This article presents the isotopic dating, petrological and geochemical features of the rocks belonging to the Kurgas complex. It gives the first description of the regional geochemical zoning that is reflected in a decrease in SiO2 contents from the north to the south along the Bashkirian meganticlinorium, and an increase in MgO contents in the same direction, which is attributed by the authors to an increase in the permeability of the crust to the south during opening of the Mashak riftogenic structure.New data on isotopic ages were obtained for the dyke that cuts the Satka formation of the Lower Riphean – 1318±10 (40Ar/39Ar), the intrusion in the exocontact zone of the Berdyaush rapakivi granite massif – 1349±11 Ma (U-Pb), and the andesite dyke among the metamorphic rocks of the Taratash complex – 1365.6±6.6 Ma (U-Pb). These ages, in combination with the previously obtained data, suggest that the complex formed during a rather long period of time (from 1385 to 1318 Ma, as a minimum), which corresponds to the beginning of the Middle Riphean. Isotopic U-Pb age of the dyke that cuts the contact zone of the Berdyaush massif, suggests that the major portion of the massif had already crystallized by that time and was exhumed into the shallow zone of brittle deformation

    FORMATION OF LONG-TERM MODEL OF RESTRUCTURING OF HOSPITAL BEDS FOR UROLOGY PROFILE

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    Abstract:One of the leading causes of reduced quality of life, disability and premature mortality were urologic diseases. Improving the provision of urologic care to the population — one of the major problems in the system. The team of authors developed a model of restructuring urological service to the region with a total population of 2 million people, and a regional center with a population of 1 000 thousand people. The article provides the calculation of normative number of beds and doctors’ rates for the urology department three-tier system of care, depending on the population of the region. The calculation of staffing urologist and urological department heads. Computer simulation is performed in accordance with the current legislation (about health care) and regulations. The standardized software development methodology inter-networking model units have practical value and can be used by the executive bodies of state power in the health sector of any region of each profile of care
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