[Comparative analysis of the radionuclide composition in fallout after the Chernobyl and the Fukushima accidents].

The nuclear accident occurred at Fukushima Dai-ichi Nuclear Power Plant (NPP) (March 11, 2011) similarly to the accident at the Chernobyl NPP (April 26, 1986) is related to the level 7 of the INES. It is of interest to make an analysis of the radionuclide composition of the fallout following the both accidents. The results of the spectrometric measurements were used in that comparative analysis. Two areas following the Chernobyl accident were considered: (1) the near zone of the fallout - the Belarusian part of the central spot extended up to 60 km around the Chernobyl NPS and (2) the far zone of the fallout--the "Gomel-Mogilev" spot centered 200 km to the north-northeast of the damaged reactor. In the case of Fukushima accident the near zone up to about 60 km considered. The comparative analysis has been done with respect to refractory radionuclides (95Zr, 95Nb, 141Ce, 144Ce), as well as to the intermediate and volatile radionuclides 103Ru, 106Ru, 131I, 134Cs, 137Cs, 140La, 140Ba and the results of such a comparison have been discussed. With respect to exposure to the public the most important radionuclides are 131I and 137Cs. For the both accidents the ratios of 131I/137Cs in the considered soil samples are in the similar ranges: (3-50) for the Chernobyl samples and (5-70) for the Fukushima samples. Similarly to the Chernobyl accident a clear tendency that the ratio of 131I/137Cs in the fallout decreases with the increase of the ground deposition density of 137Cs within the trace related to a radioactive cloud has been identified for the Fukushima accident. It looks like this is a universal tendency for the ratio of 131I/137Cs versus the 137Cs ground deposition density in the fallout along the trace of a radioactive cloud as a result of a heavy accident at the NPP with radionuclides releases into the environment. This tendency is important for an objective reconstruction of 131I fallout based on the results of 137Cs measurements of soil samples carried out at late dates after the Fukushima accident.

[Effect of parenteral administration of melatonin on the biochemical composition of the rat granulation tissue]. / Vliianie parenteral'nogo vvedeniia melatonina na biokhimicheskii sostav granuliatsionno-fibroznoi tkani krys.

The influence of long term parenteral melatonin administration on the biochemical composition of granulation tissue of surgical wounds in rats during healing was investigated. Physiological solution and solutions containing various concentrations of melatonin were subcutaneously injected to the animals within 3 weeks. Control and injected animals were wounded. Samples of gramilation tissue were investigated on the 5-th and the 8-th day of healing. The contents of oxyprolin, uronic acids, hexosamines, total lipids and their fractions, fractional composition of glycosaminoglicans and proteins composition of salt extracts were determined in the se samples. Repeated injections during three weeks caused the changes in biochemical composition of researched samples which were characteristic for stressful reaction of connective tissue. The specific changes are most expressed at long term introduction of a physiological solution to animals. The introduction of melatonin during similar period cansed protective effect, partially defending biochemical composition of granulation tissue from changes, which were induced by stressful situation.

[Radiation safety in work with chemicals containing admixtures of natural radionuclides]. / Radiatsionnaia bezopasnost' pri rabote s veshchestvami, soderzhashchimi primesi estestvennykh radionuklidov.

The authors analyze results obtained in their own research of radiation situation in several enterprises of Nuclear Energy Department. Those enterprises treat chemicals containing admixtures of natural radionuclides in production of substances previously considered safe--tantalum, zirconium, strontium carbonate. The article necessitates regulation of radiation factor in working environment and control over products and waste materials. The authors base methods providing radiation safety during work with substances containing higher levels of natural radionuclides admixtures.

[Effect of melatonin on wound healing and various biochemical characteristics of granulation-fibrous tissue in rats]. / Vliianie melatonina na zazhivlenie ran i nekotorye biokhimicheskie kharakteristiki granuliatsionno-fibroznoi tkani krys.

The influence of melatonin application on wounds healing and biochemical composition of rat regenerating granulation tissue was studied. Melatonin decreased healing rate of wounds. The differences in electrophoretic pattern of proteins extracted by neutral saline solutions were detected. Melatonin increased quantity of neutral soluble collagen fraction and gene expression of minor types of collagen in normal skin. Spectrum of glycosaminoglycans' was changed, and earlier increase of chondroitinsulfats induced by administration of melatonin was observed.

[Lipid parameters of the skin, cerebellum, and medulla oblongata during immersion stress in rats]. / Lipidnye pokazateli kozhi, mozzhechka i prodolgovatogo mozga pri vodno-immersionnom stress u krys.

The influence of short-form water immersion stress of rats on lipids in the skin, the cerebellum and the medulla oblongata was studied. The level of total lipids and absolute and relative contents of the main lipid fractions (phospholipids, nonesterified cholesterol, free fatty acids, triglycerides, and cholesterol esters) were measured. Stress induced delayed changes of the lipid component of the skin. The first significant changes of lipid fractions were only observed 20 h later after the stress procedure. These changes were retained (being at nearly constant levels) till the end of the second day. The decrease in contents of total lipids and esterified cholesterol was revealed in the cerebellum of stressed rats (in comparison to these levels in control rats). These results suggest the involvement of cholesterol metabolic system in the stress reaction. The content of total lipids decreased also in the medulla oblongata. However, levels of the main lipid fractions changed differently. The content of diglycerides increased and the content of cholesterol decreased. The data obtained suggest that degradation of triglycerides is the principle pathway of metabolic conversions of lipids. Free fatty acids formed during these processes are probably involved in the synthesis of phospholipids and cholesterol esters. The data indicate absolutely different mechanisms of interrelations between individual lipid fractions in the brain regions studied. Various roles of the brain structures in the stress response of the body may account for the differences revealed.

[Establishing of doses from the internal irradiation for the personnel of the Chernobyl AES and persons detailed in 1986-1987]. / Formirovanie doz ot vnutrennego oblucheniia dlia personala Chernobyl'skoi AES i komandirovannykh v 1986-1987 gg.

The paper is concerned with the results of measurements of characteristics of the air media in the zone of the damaged reactor as with the assessment of doses from internal irradiation on the basis of calculations of air media parameters and the results of actual measurements of the uptake and content of radionuclides in the personnel of the Chernobyl Nuclear Power Station and persons sent on mission there in 1986-1987, the results being obtained by indirect and direct biophysical methods of control of internal irradiation. The calculated data are well in accord with the results of actual measurements of the contents of radionuclides in the body. Internal irradiation of all tissues and organs, determined by the inhalation of a mixture of radionuclides, worked almost completely within the first year following the accident, the thyroid being the critical organ. In the next years internal irradiation for the personnel of the Chernobyl Nuclear Power Station was determined entirely by transuranic elements and was about 0.1 M.P.D annually for bone tissue. The value of a mean effective equivalent dose from internal irradiation in 50 years is 85 mSv for professionals, and a contribution of internal irradiation to the whole-body one over the first well as is 13%.