89 research outputs found

    Increasing the effectiveness of combined strikers in the defeat of lightly armored targets

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    The article deals with the possibility of increasing the damaging effects of small-caliber artillery ammunition in the fuel tanks of aircraft and helicopters. A comparison of the results of the calculation of the probability of the incendiary effect of strikers based on fluoropolymers on diesel fuel was made. The calculations were carried out using the methods of “Fragment Criterion” and “Energy Balance”. © 2021 Institute of Physics Publishing. All rights reserved

    Using of polymeric materials to defeat of lightly armored and easily vulnerable targets. Mathematical modeling

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    The article deals with the possibility of increasing the damaging effects of small-caliber artillery ammunition in the fuel tanks of aircraft and helicopters. A comparison of the results of the calculation of the probability of the incendiary effect of strikers based on fluoropolymers on diesel fuel was made. The calculations of the probabilities of fuel ignition by the method of 'Fragmented criterion'. As a result of the calculations, it was revealed that this method is not suitable for this type of problem statement. A combined methodology has been developed for calculating the probability of fuel ignition, taking into account the ongoing chemical reaction between fluoropolymers and aluminum. All components of the passing heat release process are taken into account - the impactor deformation energy, the impactor braking energy in the fuel, the chemical energy of the reaction undergoing. The energy of the ongoing chemical reaction was taken into account using thermochemistry methods. © Published under licence by IOP Publishing Ltd

    Using of polymeric materials to defeat of lightly armored and easily vulnerable targets. Theory and experiments

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    Small caliber artillery plays an important role in the destruction of lightly armored and easily vulnerable equipment. Currently, a search is underway to increase its damaging effect. The article deals with the possibility of increasing the damaging effects of small-caliber artillery ammunition in the fuel tanks of aircraft and helicopters. The physicochemical properties of fluoropolymer materials are considered. The process of thermodynamic decomposition of a fluoropolymer is considered. The results of experiments on the interaction of fluoroplastic and aluminum / titanium alloys are analyzed. Pictures of changes in the titanium wet structure under the impact of ammunition including fluoroplastic are shown. The Ballistic Stand installation was designed to evaluate the incendiary effect of fluoropolymer materials. Several possible designs of projectiles containing fluoroplastic are selected to evaluate their structural characteristics for incendiary effect. A comparison of the results of the calculation of the probability of the incendiary effect of strikers based on fluoropolymers on diesel fuel was made. © Published under licence by IOP Publishing Ltd

    IN VITRO INDUCTION OF BLOOD MONONUCLEAR CELL PROLIFERATION BY ENDOGENOUS RETROVIRAL HERV-Eλ4-1 ENVELOPE PEPTIDE IN PATIENTS WITH MULTIPLE SCLEROSIS

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    A comparative in vitro study of blood mononuclear cells from multiple sclerosis patients and healthy donors was performed, in order to evaluate proliferative response to a retroviral antigen, aiming to determine immunomodulatory properties of synthetic oligopeptide homologous to a highly conserved human endogenous retrovirus HERV-Eλ4-1 envelope protein. It was revealed that this oligopeptide is able to stimulate the in vitro spontaneous and mitogen-induced proliferation of blood mononuclear cells from either donor and multiple sclerosis patients. Intensity of this oligopeptide-induced stimulatory effect depends on the protein concentration, and on initial level of blood immunocompetent cells proliferation. Hence, the endogenous retrovirus HERV-Eλ4-1 envelope region protein is able to increase functional activity of immunocompetent cells from human blood, that suggesting its immunostimulatory properties. It is possible that the mitogenic effects of this protein upon immunocompetent cells of multiple sclerosis patients represent a potential mechanism of retroviral involvement into pathogenesis of the disorder

    Altered Hippocampal Neurogenesis and Amygdalar Neuronal Activity in Adult Mice with Repeated Experience of Aggression

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    Repeated experience of winning in a social conflict setting elevates levels of aggression and may lead to violent behavioral patterns. Here, we use a paradigm of repeated aggression and fighting deprivation to examine changes in behavior, neurogenesis, and neuronal activity in mice with positive fighting experience. We show that for males, repeated positive fighting experience induces persistent demonstration of aggression and stereotypic behaviors in daily agonistic interactions, enhances aggressive motivation, and elevates levels of anxiety. When winning males are deprived of opportunities to engage in further fights, they demonstrate increased levels of aggressiveness. Positive fighting experience results in increased levels of progenitor cell proliferation and production of young neurons in the hippocampus. This increase is not diminished after a fighting deprivation period. Furthermore, repeated winning experience decreases the number of activated (c-fos-positive) cells in the basolateral amygdala and increases the number of activated cells in the hippocampus; a subsequent no-fight period restores the number of c-fos-positive cells. Our results indicate that extended positive fighting experience in a social conflict heightens aggression, increases proliferation of neuronal progenitors and production of young neurons in the hippocampus, and decreases neuronal activity in the amygdala; these changes can be modified by depriving the winners of the opportunity for further fights

    Distribution maps of vegetation alliances in Europe

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    Aim The first comprehensive checklist of European phytosociological alliances, orders and classes (EuroVegChecklist) was published by Mucina et al. (2016, Applied Vegetation Science, 19 (Suppl. 1), 3–264). However, this checklist did not contain detailed information on the distribution of individual vegetation types. Here we provide the first maps of all alliances in Europe. Location Europe, Greenland, Canary Islands, Madeira, Azores, Cyprus and the Caucasus countries. Methods We collected data on the occurrence of phytosociological alliances in European countries and regions from literature and vegetation-plot databases. We interpreted and complemented these data using the expert knowledge of an international team of vegetation scientists and matched all the previously reported alliance names and concepts with those of the EuroVegChecklist. We then mapped the occurrence of the EuroVegChecklist alliances in 82 territorial units corresponding to countries, large islands, archipelagos and peninsulas. We subdivided the mainland parts of large or biogeographically heterogeneous countries based on the European biogeographical regions. Specialized alliances of coastal habitats were mapped only for the coastal section of each territorial unit. Results Distribution maps were prepared for 1,105 alliances of vascular-plant dominated vegetation reported in the EuroVegChecklist. For each territorial unit, three levels of occurrence probability were plotted on the maps: (a) verified occurrence; (b) uncertain occurrence; and (c) absence. The maps of individual alliances were complemented by summary maps of the number of alliances and the alliance–area relationship. Distribution data are also provided in a spreadsheet. Conclusions The new map series represents the first attempt to characterize the distribution of all vegetation types at the alliance level across Europe. There are still many knowledge gaps, partly due to a lack of data for some regions and partly due to uncertainties in the definition of some alliances. The maps presented here provide a basis for future research aimed at filling these gaps

    Distribution maps of vegetation alliances in Europe

    Get PDF
    Aim The first comprehensive checklist of European phytosociological alliances, orders and classes (EuroVegChecklist) was published by Mucina et al. (2016, Applied Vegetation Science, 19 (Suppl. 1), 3–264). However, this checklist did not contain detailed information on the distribution of individual vegetation types. Here we provide the first maps of all alliances in Europe. Location Europe, Greenland, Canary Islands, Madeira, Azores, Cyprus and the Caucasus countries. Methods We collected data on the occurrence of phytosociological alliances in European countries and regions from literature and vegetation-plot databases. We interpreted and complemented these data using the expert knowledge of an international team of vegetation scientists and matched all the previously reported alliance names and concepts with those of the EuroVegChecklist. We then mapped the occurrence of the EuroVegChecklist alliances in 82 territorial units corresponding to countries, large islands, archipelagos and peninsulas. We subdivided the mainland parts of large or biogeographically heterogeneous countries based on the European biogeographical regions. Specialized alliances of coastal habitats were mapped only for the coastal section of each territorial unit. Results Distribution maps were prepared for 1,105 alliances of vascular-plant dominated vegetation reported in the EuroVegChecklist. For each territorial unit, three levels of occurrence probability were plotted on the maps: (a) verified occurrence; (b) uncertain occurrence; and (c) absence. The maps of individual alliances were complemented by summary maps of the number of alliances and the alliance–area relationship. Distribution data are also provided in a spreadsheet. Conclusions The new map series represents the first attempt to characterize the distribution of all vegetation types at the alliance level across Europe. There are still many knowledge gaps, partly due to a lack of data for some regions and partly due to uncertainties in the definition of some alliances. The maps presented here provide a basis for future research aimed at filling these gaps
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