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V N Potapov

Publications and source records attributed to V N Potapov.

10 recordsLinked to original sources
PubMed2006

Patterns and inventories of radioactive contamination of island sites of the Yenisey River, Russia.

The distribution of radioactive contamination at three island sites downstream from the Krasnoyarsk Mining and Chemical Combine (KMCC) was studied with the objectives of mapping contamination levels, interpreting radionuclide distributions through consideration of alluvial processes and determining radionuclide inventories. Contamination was measured using in situ gamma spectrometry and landforms characterised using topographic surveying methods. Maximum (137)Cs contamination densities (700 kBq m(-2)) were found on low- and middle-level floodplains and low-lying interconnecting areas of Beriozovy Island (16 km from the KMCC). On Mikhin Island (180 km from the KMCC) maximum total (60)Co, (152)Eu and (154)Eu activity concentrations (30-40 kBq m(-2)) occur in low-lying areas inundated during flooding. Maximum (137)Cs and total (60)Co, (152)Eu and (154)Eu contamination densities on Cheriomukhov Island (250 km from the KMCC) were 390 and 50 kBq m(-2), respectively. Estimated (137)Cs inventories were 145, 148 and 16GBq for Beriozovy, Mikhin and Cheriomukhov Islands, respectively.

Cesium Radioisotopes↗
PubMed2005

Radioactive contamination of the Balchug (Upper Yenisey) floodplain, Russia in relation to sedimentation processes and geomorphology.

The radioactive contamination of a riverine floodplain, heavily influenced by discharges from Krasnoyarsk-26, has been studied with respect to sedimentation processes and the geomorphology of the Upper Yenisey floodplain. The study was effected by implementation of a regime of in situ observations and measurements, sampling, and the interpretation of satellite images. The results of the study indicate that on the Balchug Bypass Floodplain, radionuclide contamination is primarily influenced by the thickness of the deposited sediments, and the area can be considered as two depositional environments. The Balchug floodplain area was contaminated due to sedimentation of radionuclide-contaminated alluvium, whose depositional regime significantly changed after the construction of a hydroelectric power station in 1967. Contamination levels are lower on the upstream part of the floodplain where sediment depth is less than 0.2-0.3 m, and this contamination started to accumulate in 1967, while the downstream part of the floodplain, exhibiting deeper deposits, displays higher levels of radionuclide contamination because radionuclides began to deposit here in 1958 when the Krasnoyarsk-26 Mining and Chemical Combine (KMCC) commenced operation. Radionuclide contamination of the floodplain is also related to the elevation of the floodplain, higher regions of the floodplain typically having lower contamination than low-lying areas, which tend to be frequently inundated with sediments being deposited during such inundations. Local relief, its orientation, and vegetation cover have also combined to form sediment traps with significantly higher radionuclide contamination. Lithological analysis combined with radiometric assay indicates a total 137Cs floodplain inventory of 33.7 GBq.

Cesium Radioisotopes↗
PubMed2004

Complexity: an internet resource for analysis of DNA sequence complexity.

The search for DNA regions with low complexity is one of the pivotal tasks of modern structural analysis of complete genomes. The low complexity may be preconditioned by strong inequality in nucleotide content (biased composition), by tandem or dispersed repeats or by palindrome-hairpin structures, as well as by a combination of all these factors. Several numerical measures of textual complexity, including combinatorial and linguistic ones, together with complexity estimation using a modified Lempel-Ziv algorithm, have been implemented in a software tool called 'Complexity' (http://wwwmgs.bionet.nsc.ru/mgs/programs/low_complexity/). The software enables a user to search for low-complexity regions in long sequences, e.g. complete bacterial genomes or eukaryotic chromosomes. In addition, it estimates the complexity of groups of aligned sequences.

Algorithms↗
PubMed1997

Collimated detector technique for measuring a 137Cs deposit in soil under a clean protected layer.

A method to determine the 137Cs soil deposit in situ where the contamination is covered by a clean soil layer is described. The method is based on measurements of the count rates in three energy ranges by a collimated spectrum sensitive detector and their processing. The deposit determination accuracy is 20%. The measurement results are presented and compared with data from soil sampling. The 137Cs contamination maps of areas in Belarus and the Chelyabinsk region of Russia are presented. Measurements of the river Techa bank contamination detected the presence of secondary contamination. This method permits the change of dose rate after land decontamination and the work needed for decontamination and its efficiency to be predicted.

Cesium Radioisotopes↗
PubMedDate not supplied

[Clinical and experimental study of xenon anesthesia].

Narcotic effect of inert gas xenon (Xe) was discovered more than 50 years ago. The main causes limiting its clinical application are high price, low availability (in nature the gas is present in scarce amounts), and absence of preclinical trials sufficient for norm-setting documents and further solutions allowing clinical trials of Xe. Results of original and basic clinical and experimental studies of xenon anesthesia are presented. The studies were carried out by a group of authors in accordance with the requirements and norm-setting documents of Pharmacological Committee of Ministry of Health of the Russian Federation, needed for permitting Xe for medical application as a new narcotic agent.

Anesthesia↗
PubMedDate not supplied

[Perspective in the development and supply of equipment for xenon anesthesia].

Basic trends in development of methods and equipment for xenon-saving anesthesia are discussed. Brief description of specifications of equipment for xenon anesthesia is given. Unique models of domestic medical devices are briefly described together with methods of their adaptation to commercial equipment for anesthesia. Prospects in further upgrade of the equipment for xenon anesthesia are discussed.

Anesthesia, Inhalation↗
PubMedDate not supplied

[Medical aspects of migration in the Far East regions].

A comparative analysis was made of medical and climatic conditions in the south of the Far East. Changes in the immune status, lipid peroxidation of blood cell membranes, and the antioxidative system were studied during adaptation of adults and children who had arrived from Siberia, the European part of Russia, and Far-East regions. How a standard regional adaptation of the bioimmunological status forms was followed up under the conditions of monsoons. Critical periods in migrants' adaptation and bioimmunological criteria of development of disadaptation conditions are described. A concept of the tense-dynamic type of migrants' adaptative bioimmunological reactions under the Far East monsoon conditions is proposed.

Adaptation, Physiological↗