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301.
Liver samples of 22 Dall's porpoises (Phocoenoides dalli) collected off the Sanriku coast of Japan were analyzed for investigation on bioaccumulation of total mercury (SigmaHg), organic mercury (OrgHg), inorganic mercury (InHg) and selenium (Se). In the liver, detoxification of Hg was evident by transformation of OrgHg. Se showed different Hg detoxification patterns in the liver with a threshold range of hepatic SigmaHg concentration of about 20-30 microg/g dry weight. The molar ratios of Se/InHg or Se/SigmaHg were obviously higher than 1 when hepatic SigmaHg levels were less than the range, while both ratios were close to 1 when SigmaHg levels were higher than the threshold, suggesting a mechanism by detoxification of OrgHg into less toxic mercuric selenide (HgSe) forms in the latter.  相似文献   
302.
Appropriate treatment of asbestos-containing wastes is a significant problem. In Japan, the inertization of asbestos-containing wastes based on new treatment processes approved by the Minister of the Environment is promoted. A highly sensitive method for testing asbestos fibers in inertized materials is required so that these processes can be approved. We developed a method in which fibers from milled treated materials are extracted in water by shaking, and are counted and identified by transmission electron microscopy. Evaluation of this method by using asbestos standards and simulated slag samples confirmed that the quantitation limits are a few million fibers per gram and a few μg/g in a sample of 50 mg per filter. We used this method to assay asbestos fibers in slag samples produced by high-temperature melting of asbestos-containing wastes. Fiber concentrations were below the quantitation limit in all samples, and total fiber concentrations were determined as 47–170 × 10?6 f/g. Because the evaluation of treated materials by TEM is difficult owing to the limited amount of sample observable, this testing method should be used in conjunction with bulk analytical methods for sure evaluation of treated materials.  相似文献   
303.
Environmental Science and Pollution Research - Source-specific elucidation of domestic sewage pollution caused by various effluent sources in an urban river water, as conducted for this study,...  相似文献   
304.
This study explores the politics of distributive fairness in Locally-Unwanted-Land-Uses (LULUs) siting by looking into how a movement in LULU disputes changes its attitude towards a frame of distributive fairness over a long period of time. Some kinds of facilities are often opposed by local residents because of negative side-effects, even as they are claimed to be necessary for the well-being of the wider public. Framing refers to actors’ signifying work, and how to frame distributive fairness plays a significant role in conflicts over such controversial land uses. In the 23 wards of Tokyo, distributive fairness in waste disposal among the wards has been a crucial issue. In the early 1970s, Koto Ward, which suffered a disproportionate burden of waste disposal, launched a campaign to rectify the unfairness. In-Ward Waste Disposal (IWWD), a frame of distributive fairness, played a central role in this movement. However, Koto Ward’s attitude towards this frame of distributive fairness changed over time. By examining why Koto Ward’s advocacy for IWWD varied over time, this study shows how Koto Ward’s stance on IWWD changed in conjunction with economic, policy, and political circumstances, thereby illuminating the importance of integrating socio-politico-economic contexts in framing analysis.  相似文献   
305.
306.
A rapid approach based on two-dimensional DNA gel electrophroesis (2-DGE) mapping with selective primer pairs was employed to analyze bacterial community structure in sediments from upstream, midstream and downstream of Sagami River in Japan. The 2-DGE maps indicated that Alpha- and Delta-proteobacteria were major bacterial populations in the upstream and midstream sediments. Further bacterial community structure analysis showed that richness proportion of Alpha- and Delta-proteobacterial groups reflected a trend toward decreasing from the upstream to downstream sediments. The biomass proportion of bacterial populations in the midstream sediment showed a significantly difference from that in the other sediments, suggesting that there may be an environmental pressure on the midstream bacterial community. Lorenz curves, together with Gini coefficients were successfully applied to the 2-DGE mapping data for resolving evenness of bacterial populations, and showed that the plotted curve from high-resolution 2-DGE mapping became less linear and more an exponential function than that of the 1-DGE methods such as chain length analysis and denaturing gradient gel electrophoresis, suggesting that the 2-DGE mapping may achieve a more detailed evaluation of bacterial community. In conclusion, the 2-DGE mapping combined with the selective primer pairs enables bacterial community structure analysis in river sediment and thus it can also monitor sediment pollution based on the change of bacterial community structure.  相似文献   
307.
A micro fabrication is presented to control wettability on cylinder surfaces. A machine tool is developed to form the micro-scale structure on the cylinder in incremental stamping. The stamping tool is manufactured with fabricating the micro-scale structure on the top of the tool in FIB sputtering. The micro incremental stamping is repeated with linear motion of the tool and rotation of the workpiece. The rotation is controlled by the friction drive on the machine table because of the stable stamping with reducing bending of the workpiece. The critical stamping depth, the minimum depth in which the structure is formed, is determined in the forming tests using the structured tool. Then, a stripe type structure is formed to control wettability on the cylinder surface. Anisotropic wettability appears on the structured surface.  相似文献   
308.
An inhibitory effect of a traditional Japanese fermented food, natto, was found against plant pathogens such as Rhizoctonia solani and Fusarium oxysporum, and the bacteria which showed inhibition were isolated from the natto. Among isolated bacteria, BC-1 and GAc exhibited a strong antagonistic effect in vitro against plant pathogens on an agar medium. The supernatant of bacterial culture also showed strong activity against R. solani, which meant the antimicrobial substances were produced and secreted into the medium. Both of the bacteria were estimated as Bacillus amyloliquefaciens from a partial sequence of the 16s rRNA gene. High performance liquid chromatography analysis clearly showed the production of the lipopeptide antibiotic iturin A by BC-1 and GAc.  相似文献   
309.
The Chinese steel industry achieved even growth in the 1980s and China is now the world's fourth largest steel producing country. Two factors that have played important roles in this development of the Chinese steel industry are the reform of the system or the strengthening of enterprise autonomy accompanying market reform, and the introduction of advanced technology from Western countries as a continuing policy since the 1970s. The Chinese steel industry still lags far behind those of other steel producing countries in terms of equipment and production technology, however. The present situation and problems of the Chinese steel industry in the 1990s are discussed here, together with a review of its development in the 1980s.  相似文献   
310.
The morpho-ecological adaptations of Eleocharis sphacelata in response to water depth and the sequential effects of resultant differences in deep water conditions on the long term population dynamics were investigated based on the observations carried out in three stable homogeneous populations in Goulburn and Ourimbah, New South Wales, Australia from August 2003 to May 2005. The deep water populations attained a higher harvestable shoot biomass and a lower rhizome biomass with increased growth in root structure thus significantly enhancing the nutrient uptake rates leading to a higher accumulation of shoot bound macronutrients. However, the accretion of excessive amounts of autogenous shoot litter coupled with slower decomposition rates under anaerobic conditions in the two deep water populations led to higher nutrient enrichment in sediments and overlying water column causing subsequent eutrophication with signs of growth inhibition including typical stress symptoms like stunted growth and chlorotic shoots. The shallow water population that intermittently experienced alternative inundation-drawdown pattern depicted an unaffected continuation of seasonal growth affirming that strict water regime management practices coupled with timely mowing or the removal of accumulating litter are necessary to ensure long-term survival of healthy E. sphacelata stands when it is used in applications where deep water conditions prevail.  相似文献   
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