251 research outputs found

    Properties of nanostructured diamond-silicon carbide composites sintered by high pressure infiltration technique

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    A high-pressure silicon infiltration technique was applied to sinter diamond–SiC composites with different diamond crystal sizes. Composite samples were sintered at pressure 8 GPa and temperature 2170 K. The structure of composites was studied by evaluating x-ray diffraction peak profiles using Fourier coefficients of ab initio theoretical size and strain profiles. The composite samples have pronounced nanocrystalline structure: the volume-weighted mean crystallite size is 41–106 nm for the diamond phase and 17–37 nm for the SiC phase. The decrease of diamond crystal size leads to increased dislocation density in the diamond phase, lowers average crystallite sizes in both phases, decreases composite hardness, and improves fracture toughness

    Superconducting joining of melt-textured Y-Ba-Cu-O bulk material

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    The Tm-Ba-Cu-O solder can be successfully used to produce a superconductive joint between MT-YBCO parts. The peculiarities of solidification, phase formation, structure transformations and electromagnetic properties of MT-YBCO soldered with TmBa2Cu3O7-d are discussed.Comment: PS of 6 pages text and 5 figures, presented at ICMC'2000, Brasi

    High habitat richness limits the risk of tick-borne encephalitis in Europe: a multi-scale study

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    The natural transmission cycle of tick-borne encephalitis (TBE) virus is enhanced by complex interactions between ticks and key hosts strongly connected to habitat characteristics. The diversity of wildlife host species and their relative abundance is known to affect transmission of tick-borne diseases (such as, for example, Lyme disease). In the current context of global biodiversity loss, we explored the relationship between the habitat richness index (HRI) and the pattern of human TBE cases in Europe to assess the role of HRI in disease risk mitigation. Methods: We assessed human TBE case distribution across 879 European regions using official epidemiological data reported to the European Surveillance System (TESSy) between 2017 and 2021 from 15 countries. We statistically explored the relationship between TBE presence and a novel variable - the habitat richness index (HRI) - describing the diversity of European ecosystem types. We also validated our findings at local scale using data collected between 2017 and 2021 in 227 municipalities located in Trento and Belluno provinces, two known TBE foci in northern Italy. Findings: Our results showed a significant parabolic effect of HRI on the probability of presence of human TBE cases in the European regions included in our dataset, and a significant, negative effect of HRI on the local presence of TBE in northern Italy. At both spatial scales, TBE risk decreases in areas with higher values of HRI. Interpretation: To our knowledge, no efforts have yet been made to explore the relationship between habitat richness and TBE risk, both in local and in large scale geographical contexts, probably due to the scarcity of high-resolution, large-scale data about the abundance or density of critical host species, such as rodents and ungulates. To overcome this lack o f data, in this study we considered habitat richness as proxy of vertebrate host biodiversity to disentangle its role in driving TBE European occurrence at different spatial scales. The results suggest that biodiversity loss could considerably enhance disease risk for both humans and wildlife, which may influence biodiversity conservation policies within a One Health context approach

    Proceedings of the Scientific-Practical Conference "Research and Development - 2016"

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    This open access book relates to the III Annual Conference hosted by the Russian Federal Ministry of Education and Science in December 2016. This event has summarized, analyzed and discussed the interim results, academic outputs and scientific achievements of the Russian Federal Targeted Programme for Research and Development in priority areas of development of the Russian Scientific and Technological Complex for 2014-2020. It contains 75 selected papers from 6 areas considered priority by the Federal programme: computer science, ecology & environment sciences; energy and energy efficiency; life sciences; nanoscience & nanotechnology; and transport & communications. The chapters report the results of the 3-years research projects supported by the Programme and finalized in 2016

    Ecological and environmental factors affecting the risk of tick-borne encephalitis in Europe, 2017 to 2021

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    Background: Tick-borne encephalitis (TBE) is a disease which can lead to severe neurological symptoms, caused by the TBE virus (TBEV). The natural transmission cycle occurs in foci and involves ticks as vectors and several key hosts that act as reservoirs and amplifiers of the infection spread. Recently, the incidence of TBE in Europe has been rising in both endemic and new regions. Aim: In this study we want to provide comprehensive understanding of the main ecological and environmental factors that affect TBE spread across Europe. Methods: We searched available literature on covariates linked with the circulation of TBEV in Europe. We then assessed the best predictors for TBE incidence in 11 European countries by means of statistical regression, using data on human infections provided by the European Surveillance System (TESSy), averaged between 2017 and 2021. Results: We retrieved data from 62 full-text articles and identified 31 different covariates associated with TBE occurrence. Finally, we selected eight variables from the best model, including factors linked to vegetation cover, climate, and the presence of tick hosts. Discussion: The existing literature is heterogeneous, both in study design and covariate types. Here, we summarised and statistically validated the covariates affecting the variability of TBEV across Europe. The analysis of the factors enhancing disease emergence is a fundamental step towards the identification of potential hotspots of viral circulation. Hence, our results can support modelling efforts to estimate the risk of TBEV infections and help decision-makers implement surveillance and prevention campaigns
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