The physical motivations and performance of the TAIGA (Tunka Advanced Instrument for cosmic ray physics and Gamma Astronomy) project are presented. The TAIGA observatory addresses ground-based ...gamma-ray astronomy at energies from a few TeV to several PeV, as well as cosmic ray physics from 100 TeV to several EeV and astroparticle physics. The pilot TAIGA-1 complex locates in the Tunka valley,
km West from the southern tip of the lake Baikal. It includes integrated air Cherenkov TAIGA-HiSCORE array with 120 wide-angle optical stations distributed over on area 1.1 square kilometer about and three 4-m class Imaging Atmospheric Cherenkov Telescopes of the TAIGA-IACT array. The latter array has a shape of triangle with side lengths of about 300, 400 and 500 m. The integral sensitivity of the 1-km
TAIGA-1 detector is about
TeV cm
s
for detection of
TeV gamma-rays in 300 hours of source observations. The combination of the wide-angle Cherenkov array and IACTs could offer a cost effective-way to build a large (up to 10 km
) array for very high energy gamma-ray astronomy. The reconstruction of a given EAS energy, incoming direction, and the core position, based on the TAIGA-HiSCORE data, allows one to increase the distance between the relatively expensive IACTs up to 600–800 m. These, together with the surface and underground electron/Muon detectors, will be used for selection of gamma-ray-induced EAS. Present status of the project, together with the current array description, the first experimental results and plans for the future are reported.
This paper presents the results of an analysis of observations of the Crab Nebula gamma-ray source with the first two atmospheric Cherenkov telescopes of the TAIGA (Tunka Advanced Instrument for ...cosmic ray physics and Gamma Astronomy) astrophysical complex in the stereo mode of observations. The article analyzed observational data from 2020 to 2021. Over 36 hours of observations, a signal was obtained at a statistical significance level of 5
and a spectrum of gamma rays was plotted in the energy range from 2 to 70 TeV. The paper describes a technique for gamma–hadron separation and reconstruction of detected gamma-rays energy.
A scintillation experiment is a part of the TAIGA astrophysical complex located in the Tunka Valley, 50 km from Lake Baikal. It consists of the Tunka-Grande and TAIGA-Muon arrays. Its scientific ...program is devoted to the study of cosmic rays (CRs) and search for astrophysical gamma rays by detecting charged particles (electrons and muons) of extensive air showers (EASs). We present the current status of the scintillation experiment, methods of EAS and CR parameters’ reconstruction, the main results obtained by the Tunka-Grande array and our scientific program for the future.
This article discusses the unique experiences and methods of independent examination of the level of communicative (specifically receptive and productive) English language skills of the first year ...undergraduate students studying English as the first foreign language in a Russian university, who previously passed the Unified State Exam (USE) in English. The results analyzed came from the tests the students took at the beginning of their first academic year. This study attempts to lay the foundations for the transition to level-oriented learning or to introduce differentiation in groups where students’ levels range widely – from A1 to C1. The assessment of the English language proficiency of students studying Philology, Linguistics, Foreign Regional Studies, and Pedagogy was carried out in the format the B2 First Cambridge exam (FCE). The results of the assessment were used to analyze their level of language knowledge and language skills according to the Common European Framework of Reference for Languages: Learning, Teaching, Assessment (CEFR). A number of typical mistakes made by students were revealed, based on which the students as well as their teachers were offered a number of recommendations to improve each of the skills.
The more correct recalculation from the measured Cherenkov light fluxes at distances of 200 (Q200) and 100 (Q100) m from the Extensive Air Shower (EAS) core to the energy of the primary particle has ...been developed using the results of M-C simulation by the CORSIKA code, assuming a light primary composition of cosmic rays. Using the new conversion expressions, a differential energy spectrum was obtained according to the data of the Tunka-133 array for 7 years of operation and the TAIGA-HiSCORE array for 2 years of operation.
To investigate the direct contribution to carbon emissions of fluorinated gases used in all vitreoretinal (VR) procedures utilizing gas tamponade and assess the respective carbon footprint of the ...three different gas delivery systems.
A multicenter, retrospective, environmental impact study.
All VR procedures using fluorinated gases between 2017 to 2020 at the Manchester Royal Eye Hospital (MREH) and Birmingham and Midland Eye Centre (BMEC) (the second and third largest VR centers in the UK), and between 2019 to 2020 at the University Hospitals Coventry and Warwickshire (UHCW) were included. CO2 equivalent mass (CO2EM) was calculated from the mass of each gas used, according to the Intergovernmental Panel on Climate Change.
A total of 4877 (1883 SF6 38.6%, 2096 C2F6 43.0%, and 897 C3F8 18.4%) procedures were analyzed. UHCW and BMEC utilized single-use 30 mL and 75 mL cannisters, respectively. MREH used four cylinders of each gas over 4 years (2 kg SF6, 1 kg C2F6, 1 kg C3F8). Mean CO2EM per patient was: MREH 111.8 kg, BMEC 7.5 kg, and UHCW 2.7 kg. For MREH and BMEC, the CO2EM was 73.4 metric tons annually (if all cases were performed with i) 30 mL: 3.7 tons and ii) cylinders: 148.0 tons, x 40-fold difference), equating to 599,400 (30,500-1.2 million) km travelled by a passenger car. The current use of SF6 in VR surgery accounts for 0.11% of total SF6 use; if 30 mL cylinders were exclusively used in the UK, this could be lowered to 0.01%.
This study highlights the significant waste associated with large gas cylinders and demonstrated that 30 mL cannisters can lead to a marked reduction in carbon emissions, even after accounting for the increased carbon footprint involved in their manufacture and disposal.
Main Results from the TUNKA-GRANDE Experiment Monkhoev, R. D.; Astapov, I. I.; Bezyazeekov, P. A. ...
Bulletin of the Russian Academy of Sciences. Physics,
07/2023, Letnik:
87, Številka:
7
Journal Article
Recenzirano
The Tunka-Grande scintillation array is described. Scientific results obtained over the first five years of its operation are presented. Prospects for studying cosmic rays in the 10
16
–10
18
eV ...range of energies are discussed.
Circulating levels of the gut microbe-derived metabolite trimethylamine-N-oxide (TMAO) have recently been linked to cardiovascular disease (CVD) risk. Here, we performed transcriptional profiling in ...mouse models of altered reverse cholesterol transport (RCT) and serendipitously identified the TMAO-generating enzyme flavin monooxygenase 3 (FMO3) as a powerful modifier of cholesterol metabolism and RCT. Knockdown of FMO3 in cholesterol-fed mice alters biliary lipid secretion, blunts intestinal cholesterol absorption, and limits the production of hepatic oxysterols and cholesteryl esters. Furthermore, FMO3 knockdown stimulates basal and liver X receptor (LXR)-stimulated macrophage RCT, thereby improving cholesterol balance. Conversely, FMO3 knockdown exacerbates hepatic endoplasmic reticulum (ER) stress and inflammation in part by decreasing hepatic oxysterol levels and subsequent LXR activation. FMO3 is thus identified as a central integrator of hepatic cholesterol and triacylglycerol metabolism, inflammation, and ER stress. These studies suggest that the gut microbiota-driven TMA/FMO3/TMAO pathway is a key regulator of lipid metabolism and inflammation.
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•Unbiased transcriptional profiling links FMO3 to reverse cholesterol transport•FMO3 knockdown substantially impacts whole-body cholesterol balance•FMO3 is a negative regulator of nonbiliary reverse cholesterol transport•FMO3 knockdown results in diminished LXR activity, promoting hepatic inflammation
Reverse cholesterol transport (RCT) can be mediated by either the classic biliary route or the nonbiliary transintestinal cholesterol excretion (TICE) pathway. Warrier et al. now identify a gut microbial-driven pathway that balances the amount of cholesterol entering the biliary and nonbiliary pathways. Inhibition of the enzyme flavin monooxygenase 3 (FMO3) diverts cholesterol away from biliary excretion into the nonbiliary TICE pathway, reorganizing total body cholesterol balance.
A comprehensive study of the radioprotective action mechanisms of ultra-small, citrate-stabilized, nanocrystalline cerium oxide (CeO 2 nanoparticles, nanoceria) in vitro and in vivo was carried out. ...CeO 2 nanoparticles were shown to significantly reduce the levels of hydrogen peroxide and hydroxyl radicals in aqueous solutions under X-ray irradiation. Pretreatment of primary mouse fibroblasts by CeO 2 nanoparticles in a wide range of concentrations (10 −5 to 10 −9 M) protects cells from radiation-induced oxidative stress, maintaining a high level of dehydrogenase activity. A protective effect of CeO 2 nanoparticles is also manifested in a decrease in the number of apoptotic cells and the level of reactive oxygen species (ROS) in a culture of primary mouse fibroblasts in vitro , as well as in a significant reduction (up to 50% of the control) of cytogenetic damage of mouse bone marrow in vivo . The intraperitoneal administration of CeO 2 nanoparticles (200 nM) increased the rate of survival of mice exposed to X-ray radiation at a lethal dose, both in the prophylactic and the therapeutic schemes of administration, testifying the protection at the molecular, cellular and organism levels. The physical, chemical and biological origins of the protective action of CeO 2 nanoparticles upon exposure of living systems to ionizing radiation in vitro and in vivo are discussed.
The review summarizes the most relevant microbiological characteristics that can serve as indicators of soil ecological functions: bioresource, phytosanitary, as well as the functions of carbon ...transformation and plant nutrition. The indices of diversity and taxonomic structure of microbial communities as well as abundance of certain groups of microorganisms are estimated to characterize the bioresource function of soils. The main microbiological indicators of carbon transformation are microbial biomass carbon, the ratio of bacterial to fungal biomasses, soil respiration, enzyme activities, and the rate of soil organic matter decomposition. The appropriate microbiological indicators of the plant nutrition function of soil are the enzyme activities associated with the nitrogen and phosphorus cycles, as well as molecular species-specific markers of arbuscular mycorrhiza. Gene abundances of phytopathogens and their antagonists can serve as indicators of soil phytosanitary function. Since a high variation of some characteristics and certain difficulties in their interpretation are currently the relevant problems in microbiological indication of soil functions, the key goal is a careful selection of the parameters with the best applicability as indicators of soil ecological functions.
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