97 research outputs found
Materials of the final reports on the joint Soviet-American experiment on the Kosmos-936 biosatellite
Biological experiments onboard the Kosmos-936 investigated the effect of weightlessness on the basic components of cells, the genetic structure and energy apparatus. Genetic studies were made on the Drosophila melanogaster. Experiments were made on higher vegetation and fungi as well. The results indicate that weightlessness cannot be the principal barrier for normal development. An experiment with ectopic osteogenesis in weightlessness was carried out. Measurements were made of cosmic radiation inside and outside the biosatellite
Luminescent upconversion nanoparticles evaluating temperature-induced stress experienced by aquatic organisms due to environmental variations
Growing anthropogenic activities are significantly influencing the environment and especially aquatic ecosystems. Therefore, there is an increasing demand to develop techniques for monitoring and assessing freshwater habitats changes so that interventions can prevent irrevocable damage. We explore an approach for screening the temperature-induced stress experienced by aquatic organisms due to environmental variations. Luminescent spectra of upconversion [Y2O3: Yb, Er] particles embedded within Caridina multidentata shrimps are measured, while ambient temperature gradient is inducing stress conditions. The inverse linear dependence of logarithmic ratio of the luminescence intensity provides an effective means for temperature evaluation inside aquatic species in vivo. The measured luminescence shows high photostability on the background of complete absence of biotissues autofluorescence, as well as no obscuration of the luminescence signal from upconversion particles. Current approach of hybrid sensing has a great potential for monitoring of variations in aquatic ecosystems driven by climate changes and pollution
Case study of ozone anomalies over northern Russia in the 2015/2016 winter: measurements and numerical modelling
Episodes of extremely low ozone columns were observed over the territory of
Russia in the Arctic winter of 2015/2016 and the beginning of spring 2016. We
compare total ozone columns (TOCs) from different remote sensing techniques
(satellite and ground-based observations) with results of numerical modelling
over the territory of the Urals and Siberia for this period. We demonstrate
that the provided monitoring systems (including the new Russian Infrared
Fourier Spectrometer IKFS-2) and modern three-dimensional atmospheric models
can capture the observed TOC anomalies. However, the results of observations
and modelling show differences of up to 20 %–30 % in TOC
measurements. Analysis of the role of chemical and dynamical processes
demonstrates that the observed short-term TOC variability is not a result of
local photochemical loss initiated by heterogeneous halogen activation on
particles of polar stratospheric clouds that formed under low temperatures in
the mid-winter.</p
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Lake surface temperature [in “State of the Climate in 2017”]
Observed lake surface water temperature anomalies
in 2017 are placed in the context of the recent
warming observed in global surface air temperature
by collating long-term in situ lake
surface temperature observations from some of the
world’s best-studied lakes and a satellite-derived
global lake surface water temperature dataset. The
period 1996–2015, 20 years for which satellite-derived
lake temperatures are available, is used as the base
period for all lake temperature anomaly calculations
Results from the Soviet-American gallium experiment
A radiochemical 71Ga-71Ge experiment to determine the primary flux of neutrinos from the Sun began measurements of the solar neutrino flux at the Baksan Neutrino Observatory in 1990. The number of 71Ge atoms extracted from 30 tons of gallium in 1990 and 57 tons in 1991 was measured in twelve runs during the period of January 1990 to December 1991. For the 1990 data, we observed the capture rate to be 20 + 15 -20 (stat) ± 32 (syst) SNU, resulting in a limit of less than 79 SNU (90% CL). This is to be compared with 132 SNU predicted by the Standard Solar Model. The 1991 data, taken with 57 tons of gallium, shows a non zero 71Ge signal. A final result from the 1990 and 1991 data is still pending completion of studies of possible systematic effects. © 1993
First results from the Soviet-American gallium experiment
The Soviet-American Gallium Experiment is the first experiment able to measure the dominant flux of low energy p-p solar neutrinos. Four extractions made during January to May 1990 from 30 tons of gallium have been counted and indicate that the flux is consistent with 0 SNU and is less than 72 SNU (68% CL) and less than 138 SNU (95% CL). This is to be compared with the flux of 132 SNU predicted by the Standard Solar Model. © 1991
Роль методов локального воздействия на стенки полости и паракавитарную зону в повышении эффективности лечения деструктивного туберкулеза легких
Destructive lung tuberculosis is a heterogeneous group of various forms of the lung tuberculosis (recent, chronic, advanced) which have common features, such as the presence of cavities, a presence of Mycobacteria tuberculosis and they are hard for treatment. Peculiarities of the microcirculation, the fibrous capsule outside the cavity, the caseous and necrotizing layer inside impede medications to reach the inflammation and destruction zone when applied as intranasal as directly into the cavity. Techniques for drug delivery to the perifocal zone (needle-jet injections, intrapulmonary ionophoresis), dénaturation of the cavity’s pyogeneous layer (hydrodiathermocoagulation) and damming of the draining bronchi (blocking of the cavity) allow to increase a number of the destructive cavities closed 23-43.3% more and to eradicate the Mycobacteria tuberculosis 33-47.5% more copared with a complex conservative treatment.Деструктивный туберкулез легких представляет собой разнородную группу форм легочного туберкулеза (свежего, хронического, далекозашедшего), объединенных наличием полости распада (каверн) и бактериовыделением, и является наиболее трудным для излечения. Особые условия микроциркуляции в воспалительно-деструктивной зоне, фиброзная капсула каверны и выстилающий ее изнутри казеозно-некротический слой препятствуют попаданию медикаментов, введенных интравазально (прямо и опосредованно) или внутрикавернозно. В зависимости от формы деструктивного туберкулеза легких методы введения препаратов в перифокальную зону (иголь но-струйные инъекции, внутрилегочный ионофорез), денатурации пиогенного слоя каверн (гидродиатермокоагуляция) и перекрытия дренирующих бронхов (каверноблокация) позволяют повысить закрытие деструктивных полостей на 23-43,3% и добиться прекращения бактериовыделения на 33-47,5% выше, чем при комплексном консервативном лечении
Salinity modulates thermotolerance, energy metabolism and stress response in amphipods Gammarus lacustris
Temperature and salinity are important abiotic factors for aquatic invertebrates. We investigated the influence of different salinity regimes on thermotolerance, energy metabolism and cellular stress defense mechanisms in amphipods Gammarus lacustris Sars from two populations. We exposed amphipods to different thermal scenarios and determined their survival as well as activity of major antioxidant enzymes (peroxidase, catalase, glutathione S-transferase) and parameters of energy metabolism (content of glucose, glycogen, ATP, ADP, AMP and lactate). Amphipods from a freshwater population were more sensitive to the thermal challenge, showing higher mortality during acute and gradual temperature change compared to their counterparts from a saline lake. A more thermotolerant population from a saline lake had high activity of antioxidant enzymes. The energy limitations of the freshwater population (indicated by low baseline glucose levels, downward shift of the critical temperature of aerobic metabolism and inability to maintain steady-state ATP levels during warming) was observed, possibly reflecting a trade-off between the energy demands for osmoregulation under the hypo-osmotic condition of a freshwater environment and protection against temperature stress
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The Soviet-American gallium experiment at Baksan
A gallium solar neutrino detector is sensitive to the full range of the solar neutrino spectrum, including the low-energy neutrinos from the fundamental proton-proton fusion reaction. If neutrino oscillations in the solar interior are responsible for the suppressed {sup 8}B flux measured by the Homestake {sup 37}Cl experiment and the Kamiokande water Cherenkov detector, then a comparison of the gallium, chlorine, and water results may make possible a determination of the neutrino mass difference and mixing angle. A 30-ton gallium detector is currently operating in the Baksan laboratory in the Soviet Union, with a ratio of expected solar signal to measured background (during the first one to two {sup 71}Ge half lives) of approximately one. 28 refs
Pan-Eurasian Experiment (PEEX): Towards a holistic understanding of the feedbacks and interactions in the land-Atmosphere-ocean-society continuum in the northern Eurasian region
The northern Eurasian regions and Arctic Ocean will very likely undergo substantial changes during the next decades. The Arctic-boreal natural environments play a crucial role in the global climate via albedo change, carbon sources and sinks as well as atmospheric aerosol production from biogenic volatile organic compounds. Furthermore, it is expected that global trade activities, demographic movement, and use of natural resources will be increasing in the Arctic regions. There is a need for a novel research approach, which not only identifies and tackles the relevant multi-disciplinary research questions, but also is able to make a holistic system analysis of the expected feedbacks. In this paper, we introduce the research agenda of the Pan-Eurasian Experiment (PEEX), a multi-scale, multi-disciplinary and international program started in 2012 (https://www.atm.helsinki.fi/peex/). PEEX sets a research approach by which large-scale research topics are investigated from a system perspective and which aims to fill the key gaps in our understanding of the feedbacks and interactions between the land-Atmosphere-Aquatic-society continuum in the northern Eurasian region. We introduce here the state of the art for the key topics in the PEEX research agenda and present the future prospects of the research, which we see relevant in this context
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