The effect of long-acting radiation on the diversity of heterotrophic bacteria in the soils of a 10-kilometer area around the Chernobyl Atomic Electric Power Station

The catastrophe at Chernobyl Atomic Power Station (ChAPS) of 1986 has created a natural model for studying the after-effects of prolonged action of radiation on the biota. Our work is aimed to estimate the variability of heterotrophic bacteria in the soil of 10-km zone of ChAPS which have formed as affected by prolonged action of radiation, as well as to create the corresponding collection of bacteria. Microbiological analysis of soils was carried out in 1993-1994 (in spring, summer, autumn), allowing for bacteria destroying different organic substance (in soil). It is shown that in the surface layer of soils (at the depth of 0-2 cm) the total number of cells of heterotrophic bacteria as well as the number of found species of bacteria is considerably less than in the control samples. Atypical distribution of bacteria in the soil profile was established. Indices of the species diversity of bacteria in these soils permit one to consider that microbe content of soil of the 10-km zone of the ChAPS has become considerably less after the disaster at the ChAPS in 1986 and has not recovered by 1993. A collection of various physiological groups of bacteria including representatives of Methylobacterium genus has been created. They have been isolated from the soils of 10-km zone of the ChAPS for following genetic investigations.     

The nature of the changes in the immunity of the women who worked in the cleanup of the sequelae of the accident at the Chernobyl Atomic Electric Power Station and were evacuated from the radioactively contaminated area

During examination of 37 women taking part in elimination of consequences of Chernobyl's disaster was revealed, that complex of disaster factors action resulted the formation of disbalance in the system of immunocompetence cells and caused the oppression of functional activity of neutrophils. In 110 women living on the radioactive contaminated zone (5-40 Ci/km) the phenomena of the secondary immunodeficiency in the form of defeat as cellular as humoral factors of immunity and nonspecific resistance system was diagnosed.     

Change in neutrophils in liquidators of the consequences of the accident at the Chernobyl Atomic Electric Power Station

In result of own researches and analysis of the literature? the information about high sensitivity of neutrophils of peripheric blood to infringements of constancy of internal state of body, arising as reply to radiating influence, are received. Ionized radiation modulates greatly properties and functions of neutrophilic granulocytes, which are the most sensitive and high-modulated cells of non-specific resistance system. The changes of the functional-metabolic status of neutrophils in participants of liquidation of consequences of Chernobyl disaster have been saving during 10 years after influence of the extreme, including radiating, factors of failure.     

The dynamics of thyroid diseases in the inhabitants of Kiev and Kiev Province after the accident at the Chernobyl Atomic Electric Power Station

Autoimmune affections of the thyroid gland were found to be on the increase as were Hashimoto's disease and follicular adenoma, as evidenced by a pathomorphic study in surgically removed thyroid glands of 12684 patients over 1984-1993. Rise in the frequency of malignant tumors was moderate. Increase in the incidence of papillary microcarcinoma against the background of another surgical pathology of the thyroid gland may be an unfavourable prognostic sign of further growth of morbidity of clinically manifest forms of carcinoma in Kiev and the Kiev Province.     

The morphogenic characteristics of human transitional-cell bladder tumors in Ukraine after the accident at the Chernobyl Atomic Electric Power Station]

Ten 13-17-year-old boys with pathocharacterologic peculiarities in premorbid period were examined. Syndrome of affective excitability was observed in pure form in 5 juveniles, while it was combined with hysteric features in 3 patients and with affective instability in 2 ones. These peculiarities of personality resulted in behavioral deviations which promoted the development of alcoholism and exaggerated of disorders conditioned by this disease. Course of alcoholism in the studied cases was unfavourable (binges, intake of large doses of alcohol and of the substitutes, etc) with pronounced disorders of behaviour up to aggression and delinquency. It was established that psychologic motivation (search of psychologic comfort, satisfaction of the need of actualization of personality, etc) played an important role both in development of the disease and in forming its clinical peculiarities.     

Aquatic Assessment of the Chernobyl Nuclear Accident and Its Remediation

This modeling study evaluated the aquatic environment affected by the Chernobyl nuclear accident and the effectiveness of remediation efforts. The study results indicate that radionuclide concentrations in the Pripyat and Dnieper rivers were well above the drinking water limits immediately after the Chernobyl accident but have decreased significantly in subsequent years due to flushing, burying, and decaying. Because high concentrations of 90Sr and 137Cs, the major radionuclides affecting human health through the aquatic pathways, are associated with flooding, two earthen dikes were constructed along the Pripyat River. The left-bank dike alone was successful in reducing the 90Sr concentration in the river by half. The 100-m-high, movable New Safe Confinement (NSC), which will cover the current Chernobyl Shelter, will reduce radionuclide contamination further in these rivers and nearby groundwater. If the Chernobyl Shelter should collapse before the NSC is built, the resulting peak radionuclide concentrations in the Dnieper River are expected to still remain below the drinking water limits. The radionuclide influx to groundwater through the NSC should not have any effect on concentrations in the Pripyat River.     

Mental disorders in the participants in the cleanup of the aftermath of the accident at the Chernobyl Atomic Electric Power Station

Peculiarities of localisation of total population of hypothalamic neurons, associated with innervation of vagosolitary complex "stomach" area were studied using retrograde axonal transport of horseradish peroxidase. The enzyme was administered in microportions into the mentioned area of vagosolitary complex (100-150 ml of 20% enzyme solution). The labelled neurons were exposed in the hypothalamic area basically from ipsilateral side. Greatest part of these neurons was located within paraventricular nucleus and lateral hypothalamic area as two bands oriented in caudodorsal direction. These bands length varied widely in different animals (ranging from 0.5 to 0.2 mm) mainly due to their disperse caudal ends. Rostral part of these formations were more compact and were joined by a thin cross arch, consisting of bipolar labelled neurons along it. As for interaural line this arch was located in the distance within 6.75-07.05 mm in different animals.     

The heterogeneity of the cytogenetic variability in the bone marrow cells of laboratory and wild rodents in the exclusion zone of the Chernobyl Atomic Electric Power Station

Analysis of the characters of cytogenetic variabilities and correlative interrelations between them revealed the group specificities of karyotype instability in bone marrow cells of some lines of laboratory and of wild mice under the conditions of increased radionuclide pollution in the Chernobyl zone. The complex correlative interrelations between the frequencies of cytogenetic anomalies and the character of cell division (the number of metaphases, binucleated leukocytes per 1000 cells) were observed. The obtained data indicate the stimulatory influence of chronic low doses of ionizing radiation on the manifestation of spontaneous mutagenesis, which has own genotype specific characteristics.     

核电站设备制造中双相不锈钢的应用

奥氏体-铁素体双相不锈钢中稳定存在奥氏体相和铁素体相,该钢具有较高的机械性能和优异的耐点蚀、晶间腐蚀和应力腐蚀性能,在核电站设备制备中被广泛应用。一般双相不锈钢铸件中铁素体相的体积分数≤20%,服役温度≤425℃,双相不锈钢锻件中铁素体相约占50%,服役温度≤250℃。文中介绍了核电站设备中应用的双相不锈钢铸、锻件的化学成分、制造和焊接工艺要求及组织和性能。     

核电站反应堆压力容器用钢的研究与应用

介绍了核反应堆压力容器用钢的国内外发展状况包括成分及性能要求、冶金工艺、热处理工艺、制造及应用现状。探讨了反应堆压力容器用钢的发展方向:材料技术是核反应堆压力容器制造的关键技术,随核反应堆压力容器向大型化和一体化方向发展,具有更高强韧性和淬透性的SA508Gr4N钢将可能逐步替代目前使用的SA508Gr3钢。     

The dynamics of the radiation damage and recovery processes in coniferous stands in a 10-kilometer control zone of the accident at the Chernobyl Atomic Electric Power Station

Properties of morphogenesis, growth dynamics, anatomy and ultrastructure of wood and needle, reproductive processes in coniferous plants were studied under different level of radiation effect in the 10-km zone in 1986-1992. It was established that the full drying of pine forests began under absorbed dose 80-100 Gy/year. Threshold doses, after which repair processes were possible, reached to 10-12 Gy/year for Picea abies and 50 Gy/year for Pinus sylvestris. Three maine stages are revealed in dynamics of radiation damage and repair processes in studied conifers and their morphological and functional characteristic is presented.     

The genetic effects in the somatic cells of persons working under chronic irradiation of different intensities after the accident at the Chernobyl Atomic Electric Power Station

A complex genetic study of two groups from of Chernobyl NPP personnel (from "Shelter" unit and 3rd Block) has been carried out using classical cytogenetic and GPA methods. The first group was the most vulnerable from the viewpoint of accumulated dose (exceeding 25 cGy for the moment of study). Positive correlation between individual and group frequencies of cytogenetic markers of irradiation (stable and unstable chromosomes aberrations) and NO mutations in the GPA locus was found.     

The status of the gastric and duodenal mucosa, biopsied from those who worked in the cleanup of the aftermath of the accident at the Chernobyl Atomic Electric Power Station, in an organotypic tissue culture

Biopsies of stomach and duodenum different regions mucosa obtained from patients with gastroduodenitis (liquidators of consequences of accident in Chernobyl nuclear station--LCA CNS-- and control patients) were studied cultured in vitro. The following are the differences found. Mononuclear cells, differentiating into macrophages were exposed from control biopsies. Mononuclear cells exposed from LCA CNS biopsies formed rosette-like accumulations after mitotic dividing on a distance from the explant. Part of cells within the rosettes acquired processes and formed syncytial structure.     

Disorders of the cognitive functions in those who worked in the cleanup of the aftermath of the accident at the Chernobyl Atomic Electric Power Station

The potentialities of cerebral oximetry in the para-infrared band as a means of neuromonitoring are assessed. The method is highly informative for selecting the treatment strategy during the acute period of craniocerebral injury and cerebrovascular diseases. Simultaneous analysis of intracranial pressure, central hemodynamics, and cerebral oximetry permits differentiation of mechanisms of intracranial hypertension and its compensation. Increase of rSO2 in increased intracranial pressure corresponds to brain hyperemia, its decrease to cerebral ischemia. A long trend of rSO2 changes is informative for disease prediction.     

核电用高强韧厚规格调质钢板的力学性能和显微结构

通过实验室调质工艺研究,确定了核安全壳用钢SA738Gr．B热处理工艺,经工业化热处理后,45mm厚度SA738Gr．B钢具有良好的拉伸性能和优异的低温冲击韧性,同时具有稳定的高温拉伸性能,其显微组织为均匀细小的板条贝氏体,在板条内和界面处有大量弥散的纳米级碳化物析出。