Evaluation of the efficiency of vending business and the perspectives of its development in the territory of Tomsk

This article assesses the effectiveness of conducting a vending business in the territory of Tomsk and develops a business plan for creating a network of vending machines for hot drinks. During the study, the authors conducted a sociological survey, the purpose of which was to identify the gastronomic preferences of potential buyers and to determine the presence or absence of demand in the market of vending trade. Also, the advantages and disadvantages of this market niche, possible problems and prospects for its development are considered

DNA damage under simulated extraterrestrial conditions in bacteriophage T7

The experiment ‘‘Phage and Uracil response’’ will be accommodated in the EXPOSE facility of the International Space Station. Its objective is to examine and quantify the effect of specific space conditions on nucleic acid models, especially on bacteriophage T7 and isolated T7 DNA thin films. In order to define the environmental and technical requirements of the EXPOSE, the samples were subjected to the experiment verification test (EVT). During EVT, the samples were exposed to vacuum (10-4 – 10-6 Pa) and polychromatic UV-radiation (200–400 nm) in air, in inert atmosphere, as well as in simulated space vacuum. The effect of extreme temperature in vacuum and the influence of temperature fluctuations around 0°C were also studied. The total intraphage/isolated DNA damage was determined by quantitative PCR using 555 and 3826 bp fragments of T7 DNA. The type of the damage was resolved using a combination of enzymatic probes and neutral and alkaline agarose gel electrophoresis; the structural/chemical effects were analyzed by spectroscopic and microscopical methods. We obtained substantial evidence that DNA lesions accumulate throughout exposure, but the amount of damage depends on the thickness of the layers. According to our preliminary results, the damages by exposure to conditions of dehydration and UV-irradiation are larger than the sum of vacuum alone, or radiation alone case, suggesting a synergistic action of space vacuum and UV radiation with DNA being the critical target

The PUR experiment on the EXPOSE-R facility: Biological dosimetry of solar extraterrestrial UV radiation

The aim of our experiment Phage and Uracil Response was to extend the use of bacteriophage T7 and uracil biological dosimeters for measuring the biologically effective ultraviolet (UV) dose in the harsh extraterrestrial radiation conditions. The biological detectors were exposed in vacuum-tightly cases in the European Space Agency (ESA) astrobiological exposure facility attached to the external platform of Zvezda (EXPOSE-R). EXPOSE-R took off to the International Space Station (ISS) in November 2008 and was installed on the External platform of the Russian module Zvezda of the ISS in March 2009. Our goal was to determine the dose-effect relation for the formation of photoproducts (i.e. damage to phage DNA and uracil, respectively). The extraterrestrial solar UV radiation ranges over the whole spectrum from vacuum-UV (λ<200 nm) to UVA (315 nm<λ<400 nm), which causes photolesions (photoproducts) in the nucleic acids/their components either by photoionization or excitation. However, these wavelengths cause not only photolesions but in a wavelength-dependent efficiency the reversion of some photolesions, too. Our biological detectors measured in situ conditions the resultant of both reactions induced by the extraterrestrial UV radiation. From this aspect the role of the photoreversion in the extension of the biological UV dosimetry are discussed

Near-UV Transmittance of Basalt Dust as an Analog of the Martian Regolith: Implications for Sensor Calibration and Astrobiology

The Martian regolith is exposed to solar irradiation in the near-UV (200-390 nm).Basalt is one of the main components of the dust on Mars surface. The near-UV irradiationof basalt dust on Mars is simulated experimentally in order to determine the transmittance asa function of the mass and thickness of the dust. This data can serve to quantify theabsorption of dust deposited on sensors aiming to measure the UV intensity on Marssurface. The minimum thickness of the dust that corresponds to near-zero-transmittance inthe near-UV is measured. Hypothetical Martian microorganisms living on the dusty regolithat deeper layers would be preserved from the damaging solar UV irradiation