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The results of studying the propagation of plasma flows in the surrounding medium performed on the PF-3 plasma focus facility in the laboratory simulation of astrophysical jets from young stellar objects are presented. The modes with the plasma formations which retain their compactness when propagated over significant distances are obtained. The decrement of the flow's deceleration as a result of its interaction with the background gas is determined. A technique is developed for estimating the plasma temperature by the ratio of radiation intensities from various parts of the spectrum. It is shown that the background gas is heated by the flow radiation, which leads to a change in its ionization state. Thus, the plasma flow propagates not in a neutral gas but in a weakly ionized plasma. [ABSTRACT FROM AUTHOR]

The article presents the analysis and results of the application of traditional research methods for the distribution of model alien plant species in various habitats, as well as new visualization approaches to data used for these purposes. The determination of the characteristics of invasion of alien species by traditional research methods is promising in studying the colonization of ecotopes by individual model plant taxa. To identify patterns of conjugate migration of entire groups of plants into various types of macroecotopes, the methods of multivariate statistics as effective analysis tools are proposed and used. It is established that alien species are able to colonize various habitats, exhibiting a group strategy, depending on the intensity of the action of natural and anthropogenic factors. An analysis of the main groups of invasive species formed in: 1) natural habitats (ravine-gully ecotopes, Cretaceous and steppe territories; 2) anthropogenically transformed ecotopes (railways, parks); alien plants of agrophytocenoses (corn, sunflower, wheat and soy fields) indicates associated migrations of alien species separate groups to specific environmental conditions. The conducted study established that invasive plant species colonize the natural and anthropogenic ecotopes of the region selectively depending on the ecological and coenotic environmental conditions, which leads to the selection of plants with certain properties and, as a result, to the similarity of the species compositions of different types of ecotopes. [ABSTRACT FROM AUTHOR]

Results of measurements of soft X-ray emission with photon energies of <1 keV under conditions of a plasma focus (PF) experiment are presented. The experiments were carried out at the world's largest PF device-the PF-3 Filippov-type facility ( I ⩽ 3 MA, T/4 ≈ 15-20 µs, W ⩽ 3 MJ). X-ray emission from both a discharge in pure neon and with a tungsten wire array placed on the axis of the discharge chamber was detected. The wire array imploded under the action of the electric current intercepted from the plasma current sheath of the PF discharge in neon. The measured soft X-ray powers from a conventional PF discharge in gas and a PF discharge in the presence of a wire array were compared for the first time. [ABSTRACT FROM AUTHOR]

Species of the genus Bidens that have invaded natural communities in Europe were observed. Fourteen species have been introduced in European botanical gardens since the 18th century, but only two of them have become invasive in Russia-Bidensfrondosa and B. connata. B.frondosa demonstrates microevolutional ability in the second distribution range. Nevertheless, it has a low ability of hybridization. B. frondosa has higher competitiveness compared with that of B. connata.

There is presented clinical observation of 125 patients with primary non-Hodgkin lymphomas stage I-IV (90 patients with diffuse large B-cell and 35 patients with primary mediastinal large B-cell lymphoma) treated with chemoradiotherapy. Radiotherapy was carried out in condition of conventional (60 patients) or multifractionation (65 patients). 75 (60.0%) patients underwent positron emission tomography with 18F-FDG of the whole body (130) in different periods of the clinical course of the disease. In addition patients with diffuse large B-cell lymphoma were monitored by main indicators of peripheral blood before and at different stages of treatment. It was found that after a period of drug treatment radiotherapy increased the frequency of complete remissions in patients with diffuse large B-cell and primary mediastinal large B-cell lymphoma by 24.4% and 44.2%, respectively, contributing to satisfactory long-term results. Fractionation regime did not significantly affect the results of treatment but radiation pneumonitis was observed only in the normal dose fractionation. Positron emission tomography with 18F-FDG in this category of patients was of great importance specifying the spread of the tumor. The frequency of complete metabolic response significantly increased after radiotherapy compared to drug treatment stage. Reduction of hematological parameters after radiotherapy in patients with diffuse large B-cell lymphoma was mostly of I-II degree and did not interfere with treatment. Leukopenia, neutropenia and thrombocytopenia were more significant when irradiation was performed two times a day compared to those in condition of conventional fractionation.

Emerging body of data indicate protecting effect of low level of stress (preconditioning) on retina. Our previous studies have revealed a non-linear dose-response relationship for cytotoxic effect of both ionizing radiation and N-methyl-N-nitrosourea (MNU) on mouse retina. Moreover, non-cytotoxic dose of MNU increased tolerance of retina to following challenge dose of MNU. This result displays protection of retina through mechanism of recovery. In the present study we used the mouse model for MNU-induced retinal degeneration to evaluate the adaptive response of the retina to proton irradiation and implication of glial Muller cells in this response. In this paper, we have shown that the recovery of the retina after exposure to genotoxic agents is associated with an increased efficiency of DNA damage repair and lowered death of retinal photoreceptors.