48 research outputs found

    Antiferromagnetic resonance in ferroborate NdFe3_3(BO3_3)$_4

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    The AFMR spectra of the NdFe3_3(BO3_3)4_4 crystal are measured in a wide range of frequencies and temperatures. It is found that by the type of magnetic anisotropy the compound is an "easy-plane" antiferromagnet with a weak anisotropy in the basal plane. The effective magnetic parameters are determined: anisotropy fields Ha1H_{a1}=1.14 kOe and Ha2H_{a2}=60 kOe and magnetic excitation gaps Δν1\Delta\nu_1=101.9 GHz and Δν2\Delta \nu_2=23.8 GHz. It is shown that commensurate-incommensurate phase transition causes a shift in resonance field and a considerable change in absorption line width. At temperatures below 4.2 K nonlinear regimes of AFMR excitation at low microwave power levels are observed

    Using electronic structure changes to map the H-T phase diagram of alpha'-NaV2O5

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    We report polarized optical reflectance studies of \alpha'-NaV2O5 as a function of temperature (4-45 K) and magnetic field (0-60 T). Rung directed electronic structure changes, as measured by near-infrared reflectance ratios \Delta R(H)=R(H)/R(H=0 T), are especially sensitive to the phase boundaries. We employ these changes to map out an H-T phase diagram. Topological highlights include the observation of two phase boundaries slightly below T_{SG}, enhanced curvature of the 34 K phase boundary above 35 T, and, surprisingly, strong hysteresis effects of both transitions with applied field.Comment: 4 pages, 3 figures, PRB accepte

    Global, regional, and national comparative risk assessment of 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks, 1990-2015: A systematic analysis for the Global Burden of Disease Study 2015

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    Background: The Global Burden of Diseases, Injuries, and Risk Factors Study 2015 provides an up-to-date synthesis of the evidence for risk factor exposure and the attributable burden of disease. By providing national and subnational assessments spanning the past 25 years, this study can inform debates on the importance of addressing risks in context. Methods: We used the comparative risk assessment framework developed for previous iterations of the Global Burden of Disease Study to estimate attributable deaths, disability-adjusted life-years (DALYs), and trends in exposure by age group, sex, year, and geography for 79 behavioural, environmental and occupational, and metabolic risks or clusters of risks from 1990 to 2015. This study included 388 risk-outcome pairs that met World Cancer Research Fund-defined criteria for convincing or probable evidence. We extracted relative risk and exposure estimates from randomised controlled trials, cohorts, pooled cohorts, household surveys, census data, satellite data, and other sources. We used statistical models to pool data, adjust for bias, and incorporate covariates. We developed a metric that allows comparisons of exposure across risk factors—the summary exposure value. Using the counterfactual scenario of theoretical minimum risk level, we estimated the portion of deaths and DALYs that could be attributed to a given risk. We decomposed trends in attributable burden into contributions from population growth, population age structure, risk exposure, and risk-deleted cause-specific DALY rates. We characterised risk exposure in relation to a Socio-demographic Index (SDI). Findings: Between 1990 and 2015, global exposure to unsafe sanitation, household air pollution, childhood underweight, childhood stunting, and smoking each decreased by more than 25%. Global exposure for several occupational risks, high body-mass index (BMI), and drug use increased by more than 25% over the same period. All risks jointly evaluated in 2015 accounted for 57·8% (95% CI 56·6–58·8) of global deaths and 41·2% (39·8–42·8) of DALYs. In 2015, the ten largest contributors to global DALYs among Level 3 risks were high systolic blood pressure (211·8 million [192·7 million to 231·1 million] global DALYs), smoking (148·6 million [134·2 million to 163·1 million]), high fasting plasma glucose (143·1 million [125·1 million to 163·5 million]), high BMI (120·1 million [83·8 million to 158·4 million]), childhood undernutrition (113·3 million [103·9 million to 123·4 million]), ambient particulate matter (103·1 million [90·8 million to 115·1 million]), high total cholesterol (88·7 million [74·6 million to 105·7 million]), household air pollution (85·6 million [66·7 million to 106·1 million]), alcohol use (85·0 million [77·2 million to 93·0 million]), and diets high in sodium (83·0 million [49·3 million to 127·5 million]). From 1990 to 2015, attributable DALYs declined for micronutrient deficiencies, childhood undernutrition, unsafe sanitation and water, and household air pollution; reductions in risk-deleted DALY rates rather than reductions in exposure drove these declines. Rising exposure contributed to notable increases in attributable DALYs from high BMI, high fasting plasma glucose, occupational carcinogens, and drug use. Environmental risks and childhood undernutrition declined steadily with SDI; low physical activity, high BMI, and high fasting plasma glucose increased with SDI. In 119 countries, metabolic risks, such as high BMI and fasting plasma glucose, contributed the most attributable DALYs in 2015. Regionally, smoking still ranked among the leading five risk factors for attributable DALYs in 109 countries; childhood underweight and unsafe sex remained primary drivers of early death and disability in much of sub-Saharan Africa. Interpretation: Declines in some key environmental risks have contributed to declines in critical infectious diseases. Some risks appear to be invariant to SDI. Increasing risks, including high BMI, high fasting plasma glucose, drug use, and some occupational exposures, contribute to rising burden from some conditions, but also provide opportunities for intervention. Some highly preventable risks, such as smoking, remain major causes of attributable DALYs, even as exposure is declining. Public policy makers need to pay attention to the risks that are increasingly major contributors to global burden. Funding: Bill & Melinda Gates Foundation

    Spatial Structures in Magnetizable Fluids

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    The conditions of existence and stability of spatial structures of ferroparticles of the type of isolated and periodic strata that are formed in fixed layers of magnetizable fluid in a constant homogeneous magnetic field are studied

    РЕГУЛЯРНАЯ ФИЗИЧЕСКАЯ НАГРУЗКА СНИЖАЕТ ВЛИЯНИЕ А-АЛЛЕЛЯ ГЕНА FTO НА ПРЕДРАСПОЛОЖЕННОСТЬ К ОЖИРЕНИЮ В ГРУППЕ РУССКИХ МУЖЧИН

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    Introduction. Although the effect of the fat mass and obesity-associated (FTO) gene on adiposity is well established, there is a lack of evidence whether physical activity (PA) modifies the effect of FTO variants on obesity in Russians. Therefore, the purpose of this study was to examine PA influences and interactive effects between FTO variants and PA on measures of adiposity in Russians. Materials and methods. 110 Russian males aged 22-52 years old were examined. Anthropometry: height and weight, waist and hip circumferences were taken. The whole-body impedance was measured on the right-hand side of the body using the bioimpedance meter ABC-01 ‘Medas’ (SRC Medas, Russia) according to a conventional tetrapolar scheme at a frequency of 50 kHz. For each subject participating in the study, the genotype was determined by the polymorphic systems of the T/A (rs9939609) polymorphism of the FTO gene (Lytekh, Moscow). Results. Participants who did not engage in regular PA exhibited higher BMI, fat mass, HC, and WC with statistical significance (P ≤ 0.01). Although significant associations between the three FTO genotypes and adiposity measures were found in the sedentary group. There were no significant associations between FTO genotypes and obesity-related phenotypes in the PA group. Conclusion. Comparison of morphological parameters in carriers of alternative genotypes in two subgroups with different lifestyles makes it possible to conclude that the A allele determines a greater tendency to accumulate fat in cases where there is no regular physical activity.Цель. Несмотря на то, что влияние жировой массы и связанного с ожирением гена FTO на набор веса хорошо изучено, по-прежнему недостаточно данных о том, меняет ли физическая активность воздействие вариантов гена FTO на избыточный вес у россиян. Таким образом, цель данного исследования - изучить влияние физической активности, а также воздействие вариантов гена FTO и физической активности на показатели ожирения у россиян. Материалы и методы. В исследовании приняли участие 110 мужчин из России в возрасте от 22 до 52 лет. Были получены следующие антропометрические данные: длина и масса тела, объем талии и бедер. Импеданс тела был измерен с правой стороны с использованием биоимпедансметра АВС-01 МЕДАСС (ООО НТЦ Медасс, Россия) на частоте 50 кГц в соответствии с традиционной тетраполярной схемой. У каждого участника исследования генотип определялся по полиморфным системам T/A (rs9939609) полиморфизма гена FTO (лаборатория Литех, Москва). Результаты. Участники исследования, не практиковавшие регулярную физическую нагрузку, продемонстрировали более высокие статистически значимые показатели ИМТ, жировой массы, объема талии и бедер (P ≤ 0,01). При этом в группе лиц, ведущих малоподвижный образ жизни, были установлены значительные корреляции между тремя генотипами гена FTO и показателями ожирения. Участники, практикующие регулярную физическую нагрузку, не продемонстрировали статистически значимых связей между генотипами гена FTO и связанными с ожирением фенотипами. Заключение. Сравнение морфологических параметров у носителей альтернативных генотипов из двух подгрупп, ведущих разный образ жизни, позволяет сделать вывод, что А-аллель определяет большую предрасположенность к накоплению жировой массы в отсутствие регулярной физической нагрузки

    Physical activity attenuates the effect of the FTO T/A polymorphism on obesity-related phenotypes in adult Russian males [РЕГУЛЯРНАЯ ФИЗИЧЕСКАЯ НАГРУЗКА СНИЖАЕТ ВЛИЯНИЕ А-АЛЛЕЛЯ ГЕНА FTO НА ПРЕДРАСПОЛОЖЕННОСТЬ К ОЖИРЕНИЮ В ГРУППЕ РУССКИХ МУЖЧИН]

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    Introduction. Although the effect of the fat mass and obesity-associated (FTO) gene on adiposity is well established, there is a lack of evidence whether physical activity (PA) modifies the effect of FTO variants on obesity in Russians. Therefore, the purpose of this study was to examine PA influences and interactive effects between FTO variants and PA on measures of adiposity in Russians. Materials and methods. 110 Russian males aged 22-52 years old were examined. Anthropometry: height and weight, waist and hip circumferences were taken. The whole-body impedance was measured on the right-hand side of the body using the bioimpedance meter ABC-01 'Medas' (SRC Medas, Russia) according to a conventional tetrapolar scheme at a frequency of 50 kHz. For each subject participating in the study, the genotype was determined by the polymorphic systems of the T/A (rs9939609) polymorphism of the FTO gene (Lytekh, Moscow). Results. Participants who did not engage in regular PA exhibited higher BMI, fat mass, HC, and WC with statistical significance (P ≤ 0.01). Although significant associations between the three FTO genotypes and adiposity measures were found in the sedentary group. There were no significant associations between FTO genotypes and obesity-related phenotypes in the PA group. Conclusion. Comparison of morphological parameters in carriers of alternative genotypes in two subgroups with different lifestyles makes it possible to conclude that the A allele determines a greater tendency to accumulate fat in cases where there is no regular physical activity. © 2019 South Ural State University - Institute of Sport, Tourism and Service. All rights reserved

    Professional foreign language competence formation using educational multimedia technologies

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    The purpose of the study is to analyze the use of multimedia teaching technologies as a means of developing future linguists' professional foreign language competence and to substantiate the effectiveness of their use in professional training. A combination of modern methods of pedagogical research has been used to fulfil the set goals: theoretical methods, such as analysis, generalization, comparison, synthesis, and systematization of scientific, educational-methodological literature, to determine the current state of the research subject; empirical and diagnostic methods (observation, conversations, interviews, questionnaires, testing) to determine the effectiveness of using multimedia teaching aids and determine practical recommendations for their use; prognostic methods to ascertain and diagnose the level of professional foreign language competence in future linguists; pedagogical experiments to experimentally check the effectiveness of the application of multimedia teaching technologies (multimedia educational presentations) in the process of developing the professional foreign language competence of future linguists; and methods of mathematical statistics for quantitative and qualitative processing of research results and statistical verification of their objectivity using the Pearson χ2 test. The usefulness of multimedia technologies in the development of future linguists' foreign language competence has been substantiated. The practical aspects of creating multimedia presentations aimed at developing professional foreign language competence have been described. It has been proved that the use of multimedia educational presentations to create a foreign-language communicative environment during future linguists' professional training will increase the level of linguists' independent acquisition of educational information, as well as provide positive motivation for educational and future professional activities. © 2021 Conscientia Beam. All Rights Reserved
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