Grothendieck ring of pretriangulated categories

We consider the abelian group $PT$ generated by quasi-equivalence classes of pretriangulated DG categories with relations coming from semi-orthogonal decompositions of corresponding triangulated categories. We introduce an operation of "multiplication" $\bullet$ on the collection of DG categories which makes this abelian group into a commutative ring. A few applications are considered: representability of "standard" functors between derived categories of coherent sheaves on smooth projective varieties and a construction of an interesting motivic measure.Comment: 33 page

AUSTRO-HUNGARIAN ENTREPRENEURS IN RUSSIA IN THE CONDITIONS OF THE FIRST WORLD WAR

In the presented material, a change in the situation of entrepreneurs from Austria-Hungary operating in the Russian Empire after the outbreak of the First World War is considered. They came under the influence of restrictive and liquidation measures directed against subjects of the opposing countries. As a result, part of the Austro-Hungarian enterprises in Russia was liquidated, the other reorganized with the exception of foreign owners. Only entrepreneurs of Slavic origin were able to maintain their position. They were forced to reorganize their activities to adapt to the conditions of the war. The process of liquidation of foreign entrepreneurship, which began in the war years, was subsequently brought to its logical conclusion by the Bolshevik government

Aerodynamic and acoustic analysis of helicopter main rotor blade tips in hover

Purpose: The design of main rotor blade tips is of interest to helicopter manufactures since the tip details affect the performance and acoustics of the rotor. The paper aims to discuss this issue. Design/methodology/approach: In this paper, computation fluid dynamics is used to simulate the flow around hovering helicopter blades with different tip designs. For each type of blade tip a parametric study on the shape is also conducted for comparison calculations were performed the constant rotor thrust condition. The collective pitch and the cone angles of the blades were determined by at an iterative trimming process. Findings: Analysis of the distributed blade loads shows that the tip geometry has a significant influence on aerodynamics and aeroacoustics especially for stations where blade loading is high. Originality/value: The aeroacoustic characteristics of the rotors were obtained using Ffowcs Williams-Hawkings equations

Medium-Early Spring Wheat Cultivars Depending on The Level of Mineral Nutrition in The Northern Forest-Steppe of The Tyumen Region

This article analyzes the results by the yield and grain quality of two spring wheat cultivars Tyumenskaya Yubileynaya and Tyumenocka, depending on the level of mineral nutrition in the forest-steppe zone of the Tyumen region. The length of the vegetation period corresponded to the climatic conditions of the forest-steppe zone of the Tyumen region. In the reference variant and the variant with 4 tons of NPK per hectare, it was 90 days, and in the variants with 4 and 6 t/ha, it was 92 days. In the reference variant, the average yield of the Tyumenskaya Yubileynaya cultivar over the three years was 3.31 t/ha, and that of the Tyumenocka cultivar — 2.93 t/ha. The introduction of mineral fertilizers for the planned yield of 4 t/ha allowed obtaining the yield for the Tyumenskaya Yubileynaya cultivar equal to 4.14 t/ha, which was by 0.83 t/ha more than in the reference variant. The Tyumenocka cultivar yielded 3.83 t/ha, which was by 0.90 t/ha higher than in the reference variant. Further increasing the dosages of mineral fertilizers to 5 t/ha allowed obtaining 4.73 – 4.72 t/ha for both cultivars, which was by 0.27 – 0.28 t/ha lower than planned yield. The content of gluten in the grain of cultivar Tyumenskaya Yubileynaya in the reference variant was 27.2 %, of the Tyumenocka cultivar — 24.2 %. In the variant with 4 tons of NPK per hectare, an increase in the content of gluten by 9.6 – 10.4 %, respectively, was noted. According to the economic calculations, the most favorable for spring wheat cultivation in the Tyumen region is the level of mineral fertilization equal to 5 tons of NPK per hectare

Insurance as a Component of The Marketing Mechanism to Develop Aquaculture

The study aims at assessing the current aquaculture insurance in the Russian market. Due to this, it is necessary to understand the role of the aquaculture industry in the economy and determine its development in Russia, as well as to assess the modern concepts and processes of the aquaculture insurance. According to the general conclusions of the study, the fish farmers’ need in insurance varies depending on the type and size of aquaculture enterprises, the financial structure of their business, and the types of the grown aquatic organisms. In the study it is indicated that the aqua-insurance has not yet become a marketing instrument to minimize economic risks for most fish farmers. This is mainly due to the fact that the aquaculture industry in Russia is still relatively small, and therefore there is a lack of knowledge and experience in the aquaculture insurance. However, the Russia’s strategic position, an extensive fund of inland waters and marine areas, and a diverse species composition of farmed and cultivated aquatic biological resources make the aquaculture development rather attractive for business development. Thus, in the study it is concluded that in case of the further development of fish farming, the demand for knowledge and experience in the area of aquaculture insurance will increase

Electrochemical reduction of multilayer graphene oxide in alkaline electrolyte

The results of the study of the electrochemical reduction of multilayer graphene oxide in the potentiostatic mode are presented and the possibility of using alkaline electrolyte (KOH) with the concentration below 0.1 M is shown. The identification of the electrochemically reduced graphene oxide was carried out using the XRD, FTIR and Raman-spectroscopy methods. Applying the method of Raman spectroscopy the increase in the intensity of the G and 2D bands, indicating the formation of few-layer forms of reduced graphene oxide was found. The surface morphology of the electrochemically reduced graphene oxide was studied by means of the SEM method

Global age-sex-specific fertility, mortality, healthy life expectancy (HALE), and population estimates in 204 countries and territories, 1950-2019: a comprehensive demographic analysis for the Global Burden of Disease Study 2019

Background Accurate and up-to-date assessment of demographic metrics is crucial for understanding a wide range of social, economic, and public health issues that affect populations worldwide. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 produced updated and comprehensive demographic assessments of the key indicators of fertility, mortality, migration, and population for 204 countries and territories and selected subnational locations from 1950 to 2019. Methods 8078 country-years of vital registration and sample registration data, 938 surveys, 349 censuses, and 238 other sources were identified and used to estimate age-specific fertility. Spatiotemporal Gaussian process regression (ST-GPR) was used to generate age-specific fertility rates for 5-year age groups between ages 15 and 49 years. With extensions to age groups 10–14 and 50–54 years, the total fertility rate (TFR) was then aggregated using the estimated age-specific fertility between ages 10 and 54 years. 7417 sources were used for under-5 mortality estimation and 7355 for adult mortality. ST-GPR was used to synthesise data sources after correction for known biases. Adult mortality was measured as the probability of death between ages 15 and 60 years based on vital registration, sample registration, and sibling histories, and was also estimated using ST-GPR. HIV-free life tables were then estimated using estimates of under-5 and adult mortality rates using a relational model life table system created for GBD, which closely tracks observed agespecific mortality rates from complete vital registration when available. Independent estimates of HIV-specific mortality generated by an epidemiological analysis of HIV prevalence surveys and antenatal clinic serosurveillance and other sources were incorporated into the estimates in countries with large epidemics. Annual and single-year age estimates of net migration and population for each country and territory were generated using a Bayesian hierarchical cohort component model that analysed estimated age-specific fertility and mortality rates along with 1250 censuses and 747 population registry years. We classified location-years into seven categories on the basis of the natural rate of increase in population (calculated by subtracting the crude death rate from the crude birth rate) and the net migration rate. We computed healthy life expectancy (HALE) using years lived with disability (YLDs) per capita, life tables, and standard demographic methods. Uncertainty was propagated throughout the demographic estimation process, including fertility, mortality, and population, with 1000 draw-level estimates produced for each metric. Findings The global TFR decreased from 2·72 (95% uncertainty interval [UI] 2·66–2·79) in 2000 to 2·31 (2·17–2·46) in 2019. Global annual livebirths increased from 134·5 million (131·5–137·8) in 2000 to a peak of 139·6 million (133·0–146·9) in 2016. Global livebirths then declined to 135·3 million (127·2–144·1) in 2019. Of the 204 countries and territories included in this study, in 2019, 102 had a TFR lower than 2·1, which is considered a good approximation of replacement-level fertility. All countries in sub-Saharan Africa had TFRs above replacement level in 2019 and accounted for 27·1% (95% UI 26·4–27·8) of global livebirths. Global life expectancy at birth increased from 67·2 years (95% UI 66·8–67·6) in 2000 to 73·5 years (72·8–74·3) in 2019. The total number of deaths increased from 50·7 million (49·5–51·9) in 2000 to 56·5 million (53·7–59·2) in 2019. Under-5 deaths declined from 9·6 million (9·1–10·3) in 2000 to 5·0 million (4·3–6·0) in 2019. Global population increased by 25·7%, from 6·2 billion (6·0–6·3) in 2000 to 7·7 billion (7·5–8·0) in 2019. In 2019, 34 countries had negative natural rates of increase; in 17 of these, the population declined because immigration was not sufficient to counteract the negative rate of decline. Globally, HALE increased from 58·6 years (56·1–60·8) in 2000 to 63·5 years (60·8–66·1) in 2019. HALE increased in 202 of 204 countries and territories between 2000 and 2019. Interpretation Over the past 20 years, fertility rates have been dropping steadily and life expectancy has been increasing, with few exceptions. Much of this change follows historical patterns linking social and economic determinants, such as those captured by the GBD Socio-demographic Index, with demographic outcomes. More recently, several countries have experienced a combination of low fertility and stagnating improvement in mortality rates, pushing more populations into the late stages of the demographic transition. Tracking demographic change and the emergence of new patterns will be essential for global health monitorin

Mapping child growth failure across low- and middle-income countries

Child growth failure (CGF), manifested as stunting, wasting, and underweight, is associated with high 5 mortality and increased risks of cognitive, physical, and metabolic impairments. Children in low- and middle-income countries (LMICs) face the highest levels of CGF globally. Here we illustrate national and subnational variation of under-5 CGF indicators across LMICs, providing 2000–2017 annual estimates mapped at a high spatial resolution and aggregated to policy-relevant administrative units and national levels. Despite remarkable declines over the study period, many LMICs remain far from the World Health 10 Organization’s ambitious Global Nutrition Targets to reduce stunting by 40% and wasting to less than 5% by 2025. Large disparities in prevalence and rates of progress exist across regions, countries, and within countries; our maps identify areas where high prevalence persists even within nations otherwise succeeding in reducing overall CGF prevalence. By highlighting where subnational disparities exist and the highest-need populations reside, these geospatial estimates can support policy-makers in planning locally 15 tailored interventions and efficient directing of resources to accelerate progress in reducing CGF and its health implications

Global, regional, and national cancer incidence, mortality, years of life lost, years lived with disability, and disability-Adjusted life-years for 29 cancer groups, 1990 to 2017 : A systematic analysis for the global burden of disease study

Importance: Cancer and other noncommunicable diseases (NCDs) are now widely recognized as a threat to global development. The latest United Nations high-level meeting on NCDs reaffirmed this observation and also highlighted the slow progress in meeting the 2011 Political Declaration on the Prevention and Control of Noncommunicable Diseases and the third Sustainable Development Goal. Lack of situational analyses, priority setting, and budgeting have been identified as major obstacles in achieving these goals. All of these have in common that they require information on the local cancer epidemiology. The Global Burden of Disease (GBD) study is uniquely poised to provide these crucial data. Objective: To describe cancer burden for 29 cancer groups in 195 countries from 1990 through 2017 to provide data needed for cancer control planning. Evidence Review: We used the GBD study estimation methods to describe cancer incidence, mortality, years lived with disability, years of life lost, and disability-Adjusted life-years (DALYs). Results are presented at the national level as well as by Socio-demographic Index (SDI), a composite indicator of income, educational attainment, and total fertility rate. We also analyzed the influence of the epidemiological vs the demographic transition on cancer incidence. Findings: In 2017, there were 24.5 million incident cancer cases worldwide (16.8 million without nonmelanoma skin cancer [NMSC]) and 9.6 million cancer deaths. The majority of cancer DALYs came from years of life lost (97%), and only 3% came from years lived with disability. The odds of developing cancer were the lowest in the low SDI quintile (1 in 7) and the highest in the high SDI quintile (1 in 2) for both sexes. In 2017, the most common incident cancers in men were NMSC (4.3 million incident cases); tracheal, bronchus, and lung (TBL) cancer (1.5 million incident cases); and prostate cancer (1.3 million incident cases). The most common causes of cancer deaths and DALYs for men were TBL cancer (1.3 million deaths and 28.4 million DALYs), liver cancer (572000 deaths and 15.2 million DALYs), and stomach cancer (542000 deaths and 12.2 million DALYs). For women in 2017, the most common incident cancers were NMSC (3.3 million incident cases), breast cancer (1.9 million incident cases), and colorectal cancer (819000 incident cases). The leading causes of cancer deaths and DALYs for women were breast cancer (601000 deaths and 17.4 million DALYs), TBL cancer (596000 deaths and 12.6 million DALYs), and colorectal cancer (414000 deaths and 8.3 million DALYs). Conclusions and Relevance: The national epidemiological profiles of cancer burden in the GBD study show large heterogeneities, which are a reflection of different exposures to risk factors, economic settings, lifestyles, and access to care and screening. The GBD study can be used by policy makers and other stakeholders to develop and improve national and local cancer control in order to achieve the global targets and improve equity in cancer care. © 2019 American Medical Association. All rights reserved.Peer reviewe