PHOS is one of the two electromagnetic calorimeters of of the ALICE experiment at the LHC. It is a homogeneous calorimeter of fine granularity made of PbWO4 scintillating crystals. PHOS is designed ...for high precision measurements of direct photon and neutral meson spectra and their correlations in high and low multiplicity environments. These measurements rely on a high purity photon identification. We discuss the existing methods of photon identification in the PHOS and introduce the new method which uses the information from the charged particle veto (CPV) detector. The CPV is a multi-wire proportional chamber with pad readout installed in front of the PHOS detector. The first of three CPV modules was put into operation during LHC Run 2. We discuss the efficiency of the charged-particle track reconstruction and photon identification in the CPV. After presenting its performance in pp collisions at s=13 TeV and Pb-Pb collisions at sNN=5.02 TeV we compare methods and discuss the impact on the purity of the photon spectrum.
According to modern theories, the parameters of neutral mesons such as their mass and width are closely connected with the medium in which the mesons are present. Experimental data on the study of ...mesons in a nuclear medium are in demand for development of theoretical models describing processes in the field of nonperturbative quantum chromodynamics (QCD). Masses and widths of neutral mesons produced in meson-nucleus interactions on various nuclei are measured in the Hyperon-M experiment at the U70 accelerator. The paper describes a method for precision measurement of the parameters of neutral mesons, presents the results on measurement of the mass and width of the
meson and preliminary results on the measurement of the mass and width of the
meson. The measurements indicate the absence of dependence of the quantities under study on the nuclear environment.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
In this investigation we assessed the physiological reaction of hamsters in response to chemical signals from potential sexual partners, and also after a private meeting with them, which allowed us ...to ascertain the type of mating system for this species. The reception of olfactory signals led to an increase in peroxidase activity in the blood for both sexes, indicative of activity of a non-specific line of immune defense in recipients. The increase in blood cortisol level in response to the chemical signals of a partner was only observed in females. Males spent more time near samples of estrous females, with elevated levels of cortisol in the urine. In olfactory tests, an hour after grouping all the individuals in pairs there was a significant increase in blood peroxidase activity, which indicates the reaction of a non-specific link in the immune system of partners. This increase was greater in the pairs with a mutual preference. Females from these pairs demonstrated a substantial decrease in stress hormone levels in the plasma after an hour of mating in comparison to females prior to mating, and in non-preferred coupling.
An experiment aimed at revealing the consequences of adding two species of entomopathogenic Ascomycetes,
Beauveria bassiana
and
Metarhizium robertsii
, to grain fodder showed that northern red-backed ...voles that received
M. robertsii
conidia in their food for 15 days had higher levels of triglycerides, glucose, and peroxidase in the blood; differed from other animals in social behavior patterns; and demonstrated significantly less emotionality in an open field test than control animals. The voles fed fungal conidia showed a trend towards reduced survival in captivity compared to controls. These data indicate the significant impact of entomopathogenic fungi on the metabolism, behavior, and lifespan of nontarget mammals.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The modification of the spectral function of vector mesons in nuclear matter is predicted in many theoretical models. However, the existing experimental results for testing these models are ...contradictory. Possible effects of the modification of the mass and width of ω mesons produced in the collisions of 7-GeV/
c
positively charged mesons with C, Be, Al, Cu, Sn, and Pb nuclear targets have been sought in the Hyperon-M experiment. The measured mass and width of ω mesons produced on the indicated nuclei are in agreement with each other with a high accuracy, which does not confirm the theoretical models predicting modification of the mass and/or width of the ω meson in nuclear matter.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Abstact
—The paper presents the upgrade project of the Hyperon-M experiment in the positive beam line of the U-70 accelerator complex in Protvino to study hadron-nuclear interaction mechanisms. It is ...proposed that the setup be upgraded to study the excited states of secondary nuclei formed by different types of primary hadron–nuclear interaction using precision nuclear gamma-ray spectroscopy. This could open a new direction of the nuclear physics at the junction with the physics of elementary particles at intermediate energies.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Reliability and cost-effectiveness are the main requirements for aircraft materials and structure components used in manufacturing of aviation engines. This defines the requirements for them. The ...majority of components are thin-walled and made of hard-to-machine materials: nickel and titanium alloys, heat-resistant steels. The use of such materials places restrictions on the use of certain cutting modes. During rough milling and semi-finish milling with end-mill cutters chatter occur. The vibrations deteriorate the machined surface of engine parts, tool life decreases and machine units are worn out. Different process technologies and constructive features of tools are used to decrease the intensity of chatter. The use of end mills having lands has yielded mixed results. The influence of land usage on surface condition and decrease of chatter in up-milling and down milling has been studied. The mechanism of influence on machined surface and chatter in up-milling and down milling has been determined. At the experimental stand studies were carried out on its effect on changes in the laws of motion of detail during the cutting process. It has been shown that in up-milling and down milling, a land fl = 0.05 mm wide on the rear surface along the cutting tooth reduces the intensity of chatter has been shown. The results can be used to select the feed direction to reduce the intensity of chatter when milling thin-walled parts with end mills with a land on the rear surface along the cutting edges.
Eusocial subterranean rodents of the Bathyergidae family have enormous longevity. The long lifespan of these species is associated with negligible senescence, that is, an absence of the signs of ...age-related deterioration in physical condition. The question arises as to whether these features are unique to eusocial Bathyergids or typical of other social subterranean rodents as well. In the present study, we analysed data from observations of a social subterranean Microtinae rodent, the northern mole vole (
Ellobius talpinus
Pall.), which, like mole-rats, has reproductive skew. Among the individuals captured in the wild and maintained in captivity, females that reproduced lived significantly longer than non-breeding females. We did not find any changes in muscle strength with age in any of the demographic groups studied. Faecal glucocorticoid concentrations before death were significantly higher in non-breeding females than in breeding females and males. Increased adrenocortical activity may be one mechanism responsible for the decreased lifespan of non-reproducing individuals of social subterranean rodents. We conclude that the patterns of aging, although different in some respects, are generally common for social subterranean rodents of different taxonomic groups.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, ODKLJ, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
—
To test the hypothesis that animals from habitats exposed to high anthropogenic pressure are more successful in adapting to captivity, immature narrow-skulled voles trapped in different zones of ...Karasuk Research Station (Institute of Systematics and Ecology of Animals) and beyond its boundaries were kept under laboratory conditions. Voles trapped in the immediate vicinity of service and living buildings rapidly gained weight, but their mortality rate was higher than in voles trapped at the periphery of the station or beyond its territory. The highest survival rate was observed among voles from the periphery of the station, which were especially shy and socially affiliative. Thus, narrow-skulled voles born and grown under high anthropogenic pressure proved to adapt to captivity more easily, but their survival rate was lower than in voles from habitats exposed to moderate or weak anthropogenic pressure.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Cerebrovascular diseases is one of the most important causes of morbidity and mortality in the adult population. Objective: to conduct a comparative analysis of the morpho-functional changes of the ...heart, intracardiac and systemic hemodynamics in elderly patients with cerebral atherosclerosis (CA) of 1–3 degree. Materials and methods: 229 patients with cerebral atherosclerosis of 2–3 degree took part in a comprehensive study. The patients were divided into 4 groups: Group 1 – patients with ischemic stroke (IS) in the right hemisphere (RH), Group 2 – with IS in the left hemisphere (LH), Group 3 – with cerebral atherosclerosis of 1–2 degree (no IS – comparison group) and Group 4 – a general group of patients who have IS. Design: simple, prospective, non-randomized, with the consistent inclusion of patients. Results and discussion: The compared groups differed statistically significantly by the LA diameter index (ILA), the LV diastolic index (LVIDd), the LV systolic index (LVIDs) and the wall thickness of the left ventricle (LV). Thus, the highest ILA value was observed in patients with CA (1.1 times more than in patients with IS), the highest values of LVIDd and LVIDs – in the group of patients with left-hemispheric localization of IS (1.14 and 1.18 times more, accordingly, than in patients with CA without IS). The minimal thickness of the interventricular septum (IVS) and the posterior wall of the LV was in the group of patients with CA (1.18 and 1.17 times less, respectively, compared with the group of patients with AI, without taking into account the hemispheric localization of IS). Interhemispheric differences were observed only in the assessment of LVIDd, LVIDs, and the thickness of the IVS. So, in patients with left hemispheric localization of IF LVIDd, it was 1.09 times greater, and LVIDs was 1.16 times greater than in patients with right hemispheric IF, while the IVS was 1.15 times thicker in the IS group with the right hemisphere than with left hemispheric localization of IF. In the compared groups, we also observed statistically significant differences in the assessment of the parameters of systemic and intracardiac hemodynamics. So, in patients with CA, the index of the end-diastolic volume (iEDV) was 1.14 times higher and the index of the end-systolic volume (iESV) was 1.09 times less than in patients with IS, while in patients with left-hemispheric localization of IS the lowest ejection fraction and iEDV were observed compared with the group of patients with CA (1.02 and 1.15 times, respectively). Interhemispheric differences were recorded only in terms of the magnitude of the stroke index (SI). Thus, patients with IS in LН SI was 1.2 times more than in patients with IS in RH. In the group of patients with CA and IS, non-dilatational eccentric and concentric hypertrophy of LV (LVH) was most common (37.4 % and 48.1 %–26.0 % and 61.6 %, respectively), but type III was 1.44 times more common in patients with CA, and type V – 1.28 times more often in patients with IS. Eccentric dilated LVH was most often observed in patients with IS – 2.2 times more often than in patients with CA, and concentric dilated LVH was more common in patients with CA – 1.8 times more often than in patients with IS. Interhemispheric differences were observed only in relation to types III and V LVH. Thus, in patients with right hemispheric localization of IF, concentric non-dilated LVH was 1.66 times more common, and in patients with left-hemispheric IF localization – 4.4 times eccentric non-dilated LVH. Conclusions: in patients with CA of 1–3 degree, there were statistically significant differences in the morpho-functional changes in the heart, intracardiac and systemic hemodynamics and LV geometry, and some of these differences were hemispheric.
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