Modern features of the annual flow distribution of the Volga Basin were analyzed. Statistical analysis of the annual flow data for the spring, summer-autumn, and winter seasons were carried out to ...study the changes of the water regime of the Volga Basin Rivers in 1946–2010, 1946–1977, and 1978–2010 observation years. Using the data of 207 stations, new maps of seasonal flow were created and changes in the natural river flow regulation were shown. In recent decades, the water regime of the rivers in European Russia and their annual flow distribution has changed greatly. A statistically significant decrease in the river flow irregularity after 1946 has been revealed for the most of the Volga Basin Rivers. It resulted in the increase in the natural regulation index φ, change of the seasonal flow, primarily in low-water period, and especially in winter. The increase in the φ index during the last 30 years is approximately 30%, compared to the similar previous period. Such a change of the φ value took place due to the reduction of the spring flood flow and the increased significance of the groundwater flow. In the second half of the 1970s, the rivers of the Volga Basin were characterized as “snowfeeding”; at the end of the XXth century, they became the rivers with “mixed feeding” or even “mixed feeding with prevailing groundwater feeding” according to B.D. Zaikov’s river classification. This has resulted in the significant increase in the natural flow regulation comparable to the effect of seasonal storage reservoirs.
The main sources of the background at the low threshold of the underground Large Volume Detector (LVD; Gran Sasso National Laboratory, Italy) are the natural radioactivity of the ground and radon, ...which escapes from groundwater into the atmosphere of the underground chamber through multiple microcracks in the rock. The LVD registers gamma quanta from decays of radon daughter nuclei. Deformations of the Earth’s crust produce stress and increase the number of microcracks, leading to enhanced concentration of radon. The detector’s count rate during the powerful earthquakes in central Italy in 2019 is analyzed.
The article presents data on measurements of methane fluxes at largest Russian reservoirs, carried out in August and September 2021 under long-term research project.
Direct Dark Matter searches are nowadays one of the most fervid research topics with many experimental efforts devoted to the search for nuclear recoils induced by the scattering of Weakly ...Interactive Massive Particles (WIMPs). Detectors able to reconstruct the direction of the nucleus recoiling against the scattering WIMP are opening a new frontier to possibly extend Dark Matter searches beyond the neutrino background. Exploiting directionality would also prove the galactic origin of Dark Matter with an unambiguous signal-to-background separation. Indeed, the angular distribution of recoiled nuclei is centered around the direction of the Cygnus constellation, while the background distribution is expected to be isotropic. Current directional experiments are based on gas TPC whose sensitivity is limited by the small achievable detector mass. In this paper we present the discovery potential of a directional experiment based on the use of a solid target made of newly developed nuclear emulsions and of optical read-out systems reaching unprecedented nanometric resolution.
An analysis is performed for muons passing through the Large Volume Detector (LVD) horizontally over 15 years of operation. Horizontal muons pass through the ground at around 5 km w.e. with a ...threshold energy of 4.7 TeV. The energy characteristics of the LVD allow the detection of neutrons produced by muons in the detector’s material. The great volume of statistics ensures high accuracy in determining seasonal variations in the number of neutrons. The temporal distributions of pulses with energy releases of 1 to 12 MeV are used in a time interval of 150–650 μs after a muon crosses the setup to find the specific number of neutrons.
Aims.The shape of the UV ionizing background is reconstructed from optically thin metal absorption-line systems identified in spectra of HE 2347–4342, Q 1157+3143, and HS 1700+6416 in the redshift ...interval $1.8 < z < 2.9$. Methods.The systems are analyzed by means of the Monte Carlo Inversion method completed with the spectral shape recovering procedure. Results.The UVB spectral shape fluctuates at $2.4 < z < 2.9$ mostly due to radiative transfer processes in the clumpy IGM. At $z \la 1.8$, the IGM becomes almost transparent both in the $\ion{H}{i}$ and $\ion{He}{ii}$ Lyman continua and the variability of the spectral shape comes from diversity of spectral indices describing the QSO/AGN intrinsic radiation. At $z > 2.4$, the recovered spectral shapes show intensity depression between 3 and 4 Ryd due to $\ion{He}{ii}$ Lyα absorption in the IGM clouds (line blanketing) and continuous medium (true Gunn-Petersen effect). The mean $\ion{He}{ii}$ Lyα opacity estimated from the depth of this depression corresponds within 1-2σ to the values directly measured from the $\ion{H}{i}$/$\ion{He}{ii}$ Lyα forest towards the quasars studied. The observed scatter in $\eta = N$($\ion{He}{ii}$)/N($\ion{H}{i}$) and anti-correlation between N($\ion{H}{i}$) and η can be explained by the combined action of variable spectral softness and differences in the mean gas density between the absorbing clouds. Neither of the recovered spectral shapes show features which can be attributed to the putative input of radiation from soft sources like starburst galaxies.
Immunomodulatory properties of Cumaside Aminin, D.L.; Pinegin, B.V.; Pichugina, L.V. ...
International immunopharmacology,
07/2006, Letnik:
6, Številka:
7
Journal Article
Recenzirano
The medical lead, so-called Cumaside, was created on the basis of triterpene oligoglycosides from the Far-Eastern edible sea cucumber (holothurian)
Cucumaria japonica and its immunomodulatory ...properties were studied. The haemolytic activity of Cumaside was significantly reduced in comparison with original glycosides due to the glycoside-cholesterol complex formation. The influence of Cumaside on mouse macrophages in low doses was accompanied by more then two-fold stimulation of lysosomal activity. This preparation was found to increase significantly the animal resistance against bacterial infections elicited by various pathogens. It stimulated phagocytosis, ROS formation, IL6 and TNF-α production in lymphocytes, increased the number of antibody producing cells and amplified the expression of several cell surface molecules (CD3, CD4, CD8) preliminary cultured with hydrocortisone. At the same time the preparation did not affect the delayed-type hypersensitivity, proliferative activity of lymphocytes, cytotoxic activity of NK-cells and cytokine IFNγ and IL12p70 release. The mechanism of Cumaside action is discussed.
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