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1.
Gross M 《Current biology : CB》2011,21(10):R379-R381
Following the disaster at Fukushima-Daiichi, chancellor Angela Merkel decided to speed up rather than slow down Germany's exit from nuclear power.  相似文献   

2.
Workers decommissioning the Fukushima-Daiichi nuclear power plant damaged from the Great East Japan Earthquake and resulting tsunami are at risk of injury with possible contamination from radioactive heavy atoms including actinides, such as plutonium. We propose a new methodology for on-site and rapid evaluation of heavy-atom contamination in wounds using a portable X-ray fluorescence (XRF) device. In the present study, stable lead was used as the model contaminant substitute for radioactive heavy atoms. First, the wound model was developed by placing a liquid blood phantom on an epoxy resin wound phantom contaminated with lead. Next, the correlation between the concentration of contaminant and the XRF peak intensity was formulated considering the thickness of blood exiting the wound. Methods to determine the minimum detection limit (MDL) of contaminants at any maximal equivalent dose to the wound by XRF measurement were also established. For example, in this system, at a maximal equivalent dose of 16.5 mSv to the wound and blood thickness of 0.5 mm, the MDL value for lead was 1.2 ppm (3.1 nmol). The radioactivity of 239Pu corresponding to 3.1 nmol is 1.7 kBq, which is lower than the radioactivity of 239Pu contaminating puncture wounds in previous severe accidents. In conclusion, the established methodology could be beneficial for future development of a method to evaluate plutonium contamination in wounds. Highlights: Methodology for evaluation of heavy-atom contamination in a wound was established. A portable X-ray fluorescence device enables on-site, rapid and direct evaluation. This method is expected to be used for evaluation of plutonium contamination in wounds.  相似文献   

3.
Even amidst the devastation following the earthquake and tsunami in Japan that killed more than 20,000 people, it was the accident at the Fukushima Daiichi nuclear power plant that led the country's prime minister, Naoto Kan, to fear for "the very existence of the Japanese nation." While accidents that result in mass radiological releases have been rare throughout the operating histories of existing nuclear power plants, the growing number of plants worldwide increases the likelihood that such releases will occur again in the future. Nuclear power is an important source of energy in the U.S. and will be for the foreseeable future. Accidents far smaller in scale than the one in Fukushima could have major societal consequences. Given the extensive, ongoing Nuclear Regulatory Commission (NRC) and industry assessment of nuclear power plant safety and preparedness issues, the Center for Biosecurity of UPMC focused on offsite policies and plans intended to reduce radiation exposure to the public in the aftermath of an accident. This report provides an assessment of Japan's efforts at nuclear consequence management; identifies concerns with current U.S. policies and practices for "outside the fence" management of such an event in the U.S.; and makes recommendations for steps that can be taken to strengthen U.S. government, industry, and community response to large-scale accidents at nuclear power plants.  相似文献   

4.
The Great East Japan (Tōhoku/Kanto) earthquake of March 2011 was followed by a major tsunami and nuclear incident. Several previous studies have suggested a number of psychological responses to such disasters. However, few previous studies have modelled individual differences in the risk perceptions of major events, or the implications of these perceptions for relevant behaviours. We conducted a survey specifically examining responses to the Great Japan earthquake and nuclear incident, with data collected 11-13 weeks following these events. 844 young respondents completed a questionnaire in three regions of Japan; Miyagi (close to the earthquake and leaking nuclear plants), Tokyo/Chiba (approximately 220 km from the nuclear plants), and Western Japan (Yamaguchi and Nagasaki, some 1000 km from the plants). Results indicated significant regional differences in risk perception, with greater concern over earthquake risks in Tokyo than in Miyagi or Western Japan. Structural equation analyses showed that shared normative concerns about earthquake and nuclear risks, conservation values, lack of trust in governmental advice about the nuclear hazard, and poor personal control over the nuclear incident were positively correlated with perceived earthquake and nuclear risks. These risk perceptions further predicted specific outcomes (e.g. modifying homes, avoiding going outside, contemplating leaving Japan). The strength and significance of these pathways varied by region. Mental health and practical implications of these findings are discussed in the light of the continuing uncertainties in Japan following the March 2011 events.  相似文献   

5.
Conclusion I believe that the KSSP's claim that all technological issues should be evaluated and assessed only in the context of their impact on the people are borne out by the case studies. Apart from the Silent Valley and the Mothi Chemicals controversies, the KSSP had a positive role to play in other technological and environmental controversies, such as those over river pollution from untreated chemical effluent being dumped in several rivers of the State by chemical and paper companies, nuclear power plant siting, and drug policy. The KSSP's position paper on industries indicates that Kerala has a high concentration of chemical industries, and urges the government to issue no more new licenses for chemical companies. Instead they urge the government to bring in more engineering and electonics industries into the State. The State government has been generally responsive to such calls by actively promoting electronics industry in the State. K.K. Subramanian and K.J. Joseph demonstrate how a capital-deficient State like Kerala can stimulate economic growth and employment opportunities in the electronics sector by taking advantage of the considerably well-educated human resources of the State. The KSSP is in the thick of a debate about the advisability of the establishment of a nuclear power plant in the State as a long range plan to alleviate the acute power shortage predicted for the year 2000. The consensus seems to be that since Kerala is a densely populated State, a continuum of villages and towns and cities from one end to the other situated on the coastal belt, there is no proper site on which a nuclear power plant can be built. However, given the fact that the power availability should be increased and diversified and also that the statistical probability of a nuclear accident is remote, a strong minority in the KSSP is picking up support for a nuclear power plant among the media and the people. It appears that KSSP's campaign to reach out to the people to make science and technology instruments of change is quite successful. It is not clear how much their efforts are influencing scientists and technologists at large, who are not associated with the KSSP, to help unleash the potential inherent in science and technology to improve the quality of life of the people. Even though there are no quantitative studies to measure KSSP's contributions to the high literacy rate, low infant mortality rate, and similar indicators of social progress in the State, it is safe to assume that the KSSP's campaign of Science for Social Revolution has made a positive contribution to these achievements.Though the KSSP claims to be a non-political voluntary organization, its objective is to raise the consciousness of the people in order to harness the benefits of technology to socio-economic development. The measure of success they have had in educating and raising the consciousness of the people, who might have otherwise remained ignorant or indifferent to technological issues and controversies, is evident. Given the fact that the KSSP is a totally non-governmental and voluntary organization surviving on its own resources, its success in achieving its set goals are remarkable. It is an encouraging sign that similar people's science and technology (S&T) movements are springing up in several States in India, following the foot-steps of the KSSP. After the killing of thousands of people by the Union Carbide chemical plant in Bhopal, the need for many more such people's S&T movements for democratic control of technology has become ever more urgent.
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6.
The molecular mechanisms by which meiotic events are regulated are at present unknown. To approach this problem, we have exploited the natural synchrony of Lilium meiocytes to compare the nuclear protein profiles of a variety of stages of meiosis. This approach has facilitated the identification of a number of nuclear proteins that appear and disappear in a stagespecific fashion. Here we report the presence of an abundant nuclear protein that first appears during premeiotic interphase, a period during which the irreversible commitment to meiosis occurs. Antibodies directed against this protein demonstrate its meiosis specificity as well as conservation of the epitope(s) in both mono-and dicotyledonous plant species. Chromatin fractionation studies indicate that this protein, which we have termed meiotin-1, is associated with strings of nucleosomes. Implications for meiotic chromatin packaging and chromosome structure are discussed.by J.H. Taylor  相似文献   

7.
The shrub Rosa rugosa (Japanese Rose), native to East Asia, is considered one of the most troublesome invasive plant species in natural or semi-natural habitats of northern Europe and has proven very difficult to control. We aimed at disentangling the species’ invasion history in Europe, including determining the number of introductions and their geographic origin, and at investigating whether populations in the introduced and native ranges differ in genetic diversity, structure and degree of differentiation. We found that introduced (n = 16) and native (n = 16) populations had similar levels of genetic diversity at seven nuclear SSR (microsatellite) loci. European populations lack isolation by distance and are less genetically differentiated than are populations in East Asia. Multiple and at least three independent colonization events, one of which was particularly successful, gave rise to current R. rugosa populations in Europe. The geographic distribution patterns of these three genetic clusters could not be explained by natural dispersal alone, indicating that human mediated secondary dispersal is driving the expansion in Europe. One cluster representing three of the European populations was most likely derived from NW Japan, whereas the origin of the remaining thirteen populations could not clearly be resolved. The introduction and expansion in Europe occurred with no significant loss of genetic diversity. We conclude that high propagule pressure at the primary establishment phase is the most parsimonious explanation for this pattern. A potential for long distance seed dispersal, coastal habitat connectivity and an outcrossing breeding system are factors likely to have enabled populations of R. rugosa to avoid detrimental effects of genetic bottlenecks and will further increase the species’ range size and abundance in Europe. We recommend that human-mediated dispersal should be prevented in order to halt the continued expansion.  相似文献   

8.
The specific/volumetric activity of radionuclides has been determined at global background levels in surface waters, bottom sediments, and hydrobionts at the site of the planned hydrotechnical facilities of the Baltic nuclear power plant (NPP). The presence of Sr90 and Csl37 in the water medium due to global processes of the formation of radioactivity in the natural environment and the content of 3H have been studied. It is established that the background values of the specific/volumetric activity of radionuclides are significantly lower than the admissible values according to NRB-99/2009, being at the level of the previous years (2009–2014). The results of these studies will serve as a basis for precision instrumental estimates of the effect of the Baltic NPP operation on the environment and will also be used to establish the background values of environmental parameters in the nuclear power site.  相似文献   

9.
A proposed coal-fired power plant at Rampal, Bangladesh will produce over 38 million tons of ash during 60 years of operation at 90% electric load generation capacity. The ash disposal pond would be full in twelve years even if half of all fly ash is used in concrete and brick production, leaving at least 20 million tons of ash with a disposal plan that is limited to surface impoundment and unlined fills, which are known to cause groundwater and surface water pollution. At Rampal, probable storm tides of 7.4 meters would breach the ash pond walls during the operational life of the coal plant, potentially resulting in catastrophic failure and massive spills of ash. Seasonal monsoon flooding would cause the ash pond itself to overflow, releasing huge volumes of contaminated water. Ash disposal for the proposed coal-fired power plant at Rampal, Bangladesh, would release toxic heavy metals into the waterways of the Sundarbans Delta and Bay of Bengal, which is a World Heritage Site and includes globally important mangroves, endangered aquatic species, and a fishery that feeds hundreds of thousands of poor people. The economic damage cost of the Rampal Plant could exceed $US 100 million dollars per year.  相似文献   

10.
Following the Fukushima nuclear power plant disaster, assessment of internal radiation exposure was indispensable to predict radiation-related health threats to residents of neighboring areas. Although many evaluations of internal radiation in residents living north and west of the crippled Fukushima nuclear power plant are available, there is little information on residents living in areas south of the plant, which were similarly affected by radio-contamination from the disaster. To assess the internal radio-contamination in residents living in affected areas to the south of the plant or who were evacuated into Iwaki city, a whole body counter (WBC) screening program of internal radio-contamination was performed on visitors to the Jyoban hospital in Iwaki city, which experienced less contamination than southern areas adjacent to the nuclear plant. The study included 9,206 volunteer subjects, of whom 6,446 were schoolchildren aged 4–15 years. Measurements began one year after the incident and were carried out over the course of two years. Early in the screening period only two schoolchildren showed Cs-137 levels that were over the detection limit (250 Bq/body), although their Cs-134 levels were below the detection limit (220 Bq/body). Among the 2,760 adults tested, 35 (1.3%) had detectable internal radio-contamination, but only for Cs-137 (range: 250 Bq/body to 859 Bq/body), and not Cs-134. Of these 35 subjects, nearly all (34/35) showed elevated Cs-137 levels only during the first year of the screening. With the exception of potassium 40, no other radionuclides were detected during the screening period. The maximum annual effective dose calculated from the detected Cs-137 levels was 0.029 and 0.028 mSv/year for the schoolchildren and adults, respectively, which is far below the 1 mSv/year limit set by the government of Japan. Although the data for radiation exposure during the most critical first year after the incident are unavailable due to a lack of systemic measurements, the present results suggest that internal radio-contamination levels more than one year after the incident were minimal for residents living south of the crippled Fukushima nuclear plant, and that the annual additional effective doses derived from internal Cs contamination were negligible. Thus, internal radio-contamination of residents living in southern radio-contaminated areas appears to be generally well controlled.  相似文献   

11.
Nuclear power plant workers are exposed to ionizing radiation at relatively low doses and for prolonged periods of time. To investigate the extent of genetic damage in these workers, a group of 133 nuclear power plant workers and 39 healthy controls were compared using the cytokinesis-block micronucleus assay. The frequency of micronuclei was significantly increased in peripheral lymphocytes of nuclear power plant workers (20.5 +/- 9.7% compared to 13.7 +/- 5.9%). A significant dose-response relationship was observed between micronucleus (MN) frequency and both the accumulated dose and the duration of employment (P < 0.01 for both variables after adjusting for age, gender and cigarette smoking) with an evident leveling off for exposures over 200 mSv. Accumulated dose and duration of employment were significantly correlated but exerted independent effects on MN frequency. For non-occupational parameters, age was significantly associated with the frequency of micronuclei, while gender was not. Smoking habit showed no overall effect, whereas increased chromosome damage was evident in smokers of more than 20 cigarettes per day. In conclusion, a dose-related association between MN frequency and exposure to ionizing radiation was evident in nuclear power plant workers, encouraging the application of the cytokinesis-block micronucleus assay in biomonitoring studies of human populations with prolonged exposure to ionizing radiation.  相似文献   

12.
Radioactive materials released in 2011 during the accident at Japan's Fukushima nuclear power plant are expected to become concentrated in wildlife via the food web, triggering DNA damage. However, the extent of this wildlife DNA damage remains unknown. We explored the effects of exposure to environmental radiation on the DNA of wild boars (Sus scrofa leucomystax) and earthworms (Megascolecidae) and examined the modes of transfer of radioactivity to these animals. We used a comet assay to analyze the DNA damage in animals collected from regions with low (0.28 μSv/h) and high (2.85 μSv/h) levels of atmospheric radiation. We constructed a model food web featuring the wild boar as the top predator, and we measured the radioactivity levels in soil, plant material, earthworms, and wild boar. The extent of DNA damage in wild boars did not differ significantly between animals captured in the two regions, but earthworms from the “high-dose” region had a significantly greater extent of DNA damage than did those from the “low-dose” region. Radioactive material can be accumulated either directly from the soil or indirectly via plant ingestion. Wildlife inhabiting radioactively contaminated areas is at high risk of DNA damage although the risk varies among species because of the differences in foraging habits. The long-term results of the observed DNA damage must be studied.  相似文献   

13.
We used DNA sequences of lecithotrophic monodontine topshells, belonging to the genera Diloma, Melagraphia, and Austrocochlea, to ascertain how this group became established over a large area of the South Pacific Ocean. The phylogeny of the topshells was estimated using portions of two mitochondrial genes (16S and cytochrome oxidase 1) and one nuclear gene (actin). A range of divergence rates was used to estimate the approximate timing of cladogenetic events within their phylogenetic tree. These estimates allow us to unambiguously reject vicariant explanations for several major divergence events and to infer several dispersal events across wide stretches of ocean. The first were two initial dispersal events from Australia (1) to an area between Samoa and Japan and (2) to New Zealand. Subsequently, at least one, and possibly two, recent eastward dispersals took place from New Zealand to Chile and the Juan Fernandez Islands, and one further dispersal occurred from somewhere in the tropical Pacific to Samoa. Moreover, owing to the short-lived nature of the topshell larvae, transoceanic larval dispersal is unlikely. The apparent paradox of a short larval phase and broad geographic range suggests that dispersal most probably occurred by rafting of adults on a suitable platform such as macroalgae; indeed, naturally buoyant bull kelp is the natural habitat of the most geographically widespread species in this group. Our molecular phylogenies imply that, despite of being an unlikely event, adult rafting in ocean currents has occurred on several occasions throughout the evolutionary history of topshells, resulting in their wide present-day distribution.  相似文献   

14.
Understanding biological diversity and the mechanisms of the Sino-Japanese disjunctions are major challenges in eastern Asia biogeography. The Sino-Japanese flora has been broadly studied as an ideal model for plant phylogeography. Diabelia Landrein (Caprifoliaceae) is an East Asian genus, with a disjunctive distribution across the Sino-Japanese region. However, relationships within Diabelia remain elusive. In this study, we reconstructed the phylogeny of Diabelia and inferred historical biogeography and evolutionary patterns based on nuclear and plastid sequences from target enrichment and genome skimming approaches, respectively. We found that the main clades within Diabelia were discordant between nuclear and plastid trees. Both nuclear and plastid phylogenetic analyses supported five main clades: Diabelia serrata (Siebold & Zucc.) Landrein, Diabelia tetrasepala (Koidz.) Landrein, Diabelia sanguinea (Makino) Landrein, Diabelia stenophylla (Honda) Landrein, and Diabelia spathulata (Siebold & Zucc.) Landrein. Species network analyses revealed that Diabelia tetrasepala is likely the result of a hybridization event. Divergence time estimation and ancestral area reconstructions showed that Diabelia originated in Japan during the early Miocene, with subsequent vicariance and dispersal events between Japan and Korea, and between Japan and China. Overall, our results support the division of Diabelia into five main clades and the recognition of five species in the genus. This research provides new insights into the species delimitation and speciation processes of taxonomically complex lineages such as Diabelia.  相似文献   

15.
During cell growth and motility in crowded tissues or interstitial spaces, cells must integrate multiple physical and biochemical environmental inputs. After a number of recent studies, the view of the nucleus as a passive object that cells have to drag along has become obsolete, placing the nucleus as a central player in sensing some of these inputs. In the present review, we will focus on changes in nuclear shape caused by external and internal forces. Depending on their magnitude, nuclear deformations can generate signaling events that modulate cell behavior and fate, or be a source of perturbations or even damage, having detrimental effects on cellular functions. On very large deformations, nuclear envelope rupture events become frequent, leading to uncontrolled nucleocytoplasmic mixing and DNA damage. We will also discuss the consequences of repeated compromised nuclear integrity, which can trigger DNA surveillance mechanisms, with critical consequences to cell fate and tissue homeostasis.  相似文献   

16.
Evidence exists that ultraviolet radiation (UV) affects molecular targets in the nucleus or at the cell membrane. UV-induced apoptosis was found to be mediated via DNA damage and activation of death receptors, suggesting that nuclear and membrane effects are not mutually exclusive. To determine whether participation of nuclear and membrane components is also essential for other UV responses, we studied the induction of interleukin-6 (IL-6) by UV. Exposing HeLa cells to UV at 4 degrees C, which inhibits activation of surface receptors, almost completely prevented IL-6 release. Enhanced repair of UV-mediated DNA damage by addition of the DNA repair enzyme photolyase did not affect UV-induced IL-6 production, suggesting that in this case membrane events predominant over nuclear effects. UV-induced IL-6 release is mediated via NFkappaB since the NFkappaB inhibitor MG132 or transfection of cells with a super-repressor form of the NFkappaB inhibitor IkappaB reduced IL-6 release. Transfection with a dominant negative mutant of the signaling protein TRAF-2 reduced IL-6 release upon exposure to UV, indicating that UV-induced IL-6 release is mediated by activation of the tumor necrosis factor receptor-1. These data demonstrate that UV can exert biological effects mainly by affecting cell surface receptors and that this is independent of its ability to induce nuclear DNA damage.  相似文献   

17.
Despite the tragic accidents in Fukushima and Chernobyl, the nuclear power industry will continue to contribute to the production of electric energy worldwide until there are efficient and sustainable alternative sources of energy. The Chernobyl nuclear accident, which occurred 26 years ago in the former Soviet Union, released an immense amount of radioactivity over vast territories of Belarus, Ukraine, and the Russian Federation, extending into northern Europe, and became the most severe accident in the history of the nuclear industry. This disaster was a result of numerous factors including inadequate nuclear power plant design, human errors, and violation of safety measures. The lessons learned from nuclear accidents will continue to strengthen the safety design of new reactor installations, but with more than 400 active nuclear power stations worldwide and 104 reactors in the Unites States, it is essential to reassess fundamental issues related to the Chernobyl experience as it continues to evolve. This article summarizes early and late events of the incident, the impact on thyroid health, and attempts to reduce agricultural radioactive contamination.  相似文献   

18.
Fly ash is a by-product of coal-fired electricity generation plants. The prevalent practice of disposal is as slurry of ash and water to open lands or ash ponds located near power plants and this has lain to waste thousands of hectares all over the world. Wind and leaching are often the causes of off-site contamination from fly ash dumpsites. Vetiver (Vetiveria zizanioides) grown on fly ash for three months showed massive, mesh-like growth of roots which could have a phytostabilizing effect. The plant achieved this without any damage to its nuclear DNA as shown by comet assay done on the root nuclei, which implies the long-term survival of the plant on the remediation site. Also, when Vetiver is used for phytoremediation of coal fly ash, its shoots can be safely grazed by animals as very little of heavy metals in fly ash were found to be translocated to the shoots. These features make planting of Vetiver a practical and environmentally compatible method for restoration of fly ash dumpsites. Lack of DNA damage in Vetiver has been compared to that in a sensitive plant i.e. Allium cepa. Our results suggested that apart from traditional end-points viz. growth parameters like root length, shoot length and dry weight, comet assay could also be included in a battery of tests for initial, rapid and effective selection of plants for restoration and phytoremediation of polluted sites.  相似文献   

19.
Performance of experimental Bacillus thuringiensis (Bt) MON events alone and pyramided with MON810 were evaluated over 3 yr in Georgia and Alabama. Ability of events to prevent whorl defoliation by the fall armyworm, Spodoptera frugiperda (J. E. Smith), and natural ear feeding damage by the corn earworm, Helicoverpa zea (Boddie) was assessed. In each year, near-isogenic hybrids with novel single transformation events and crosses pyramided with the MON810 event were compared with the standard single MON810 event and nontransformed susceptible control. Events were tested for resistance to whorl damage by manual infestations of fall armyworm and ear damage by natural infestations of corn earworm. All Bt events tested reduced fall armyworm whorl damage ratings per plant compared with the susceptible hybrid. All Bt treatments also had considerably less ear infestation and damage by corn earworm compared with the nontransgenic isoline. The MON841, MION849, and MON851 events reduced ear damage by H. zea but were not as effective as other novel events and were not advanced for further testing after the 1999 season. Pyramiding events compared with single events did not improve control of fall armyworm whorl damage, but they generally did prevent more ear damage by corn earworm. The MON84006 event singly and pyramided with MON810 had superior control of whorl-stage damage by S. frugiperda and ear damage by H. zea compared with MON810. Deployment of new events and genes could provide additional tools for managing the potential for insect resistance to Bt toxins. Furthermore, improved control of whorl and ear infestations by H. zea and S. frugiperda would increase the flexibility of planting corn, Zea mays L., and permit double cropping of corn in areas where these pests perennially reach damaging levels.  相似文献   

20.
Numerous hypotheses suggest that natural enemies can influence the dynamics of biological invasions. Here, we use a group of 12 related native, invasive, and naturalized vines to test the relative importance of resistance and tolerance to herbivory in promoting biological invasions. In a field experiment in Long Island, New York, we excluded mammal and insect herbivores and examined plant growth and foliar damage over two growing seasons. This novel approach allowed us to compare the relative damage from mammal and insect herbivores and whether damage rates were related to invasion. In a greenhouse experiment, we simulated herbivory through clipping and measured growth response. After two seasons of excluding herbivores, there was no difference in relative growth rates among invasive, naturalized, and native woody vines, and all vines were susceptible to damage from mammal and insect herbivores. Thus, differential attack by herbivores and plant resistance to herbivory did not explain invasion success of these species. In the field, where damage rates were high, none of the vines were able to fully compensate for damage from mammals. However, in the greenhouse, we found that invasive vines were more tolerant of simulated herbivory than native and naturalized relatives. Our results indicate that invasive vines are not escaping herbivory in the novel range, rather they are persisting despite high rates of herbivore damage in the field. While most studies of invasive plants and natural enemies have focused on resistance, this work suggests that tolerance may also play a large role in facilitating invasions.  相似文献   

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