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1.
The Mo contents and the relations between Mo and Cu or Crcontents were investigated in the organs of Japanese wild ducks(spotbill duck, pintail, wigeon, scaup and tufted duck). Thehighest Mo content in kidney and liver of the dabbling duckswere more than 30 g g-1 dry weight (g g-1 d.wt.), though that of diving ducks were less than 11 gg-1 d. wt. The contents were lower in the ducks migratingwithin Japan, Eurasia and North America than those in the birdsmigrating between Japan and Eurasia. The contents of liver inall species were more than 50 and less than 5 g g-1 d.wt. for Cu and Cr, respectively. Significant correlations werefound between Mo and both elements in pintail and scaup, and Moand Cr in tufted duck. These results suggest that thecontamination of wild ducks reflects the reproductive area, andnot the collected area. Mo contents closely correlated with theCu and/or Cr contaminations.  相似文献   
2.
This article serves as a position paper of a consortium of universities in the Asia–Pacific region working to address challenges of sustainable development and rapidly changing social, economic and natural environments. Member universities of ProSPER.Net (Promotion of Sustainability in Postgraduate Education and Research Network) have embarked on a project to develop an alternative university appraisal system that would potentially become a viable alternative to the existing higher education ranking and assessment systems perceived as constraining, yet, powerful. The article discusses the changing landscape for knowledge creation and the need for universities to assume new roles in a new kind of modernity—variously termed as “liquid modernity” (Z. Bauman), “reflexive modernization” (U. Beck) or other neologisms. It recognises that the mainstream ranking and assessment systems are powerful guiding systems for higher education institutions (HEIs) and, if modified, could be a significant force for transformation towards a more sustainable future. Recognising the need for HEIs to address societal challenges and needs, the Alternative University Appraisal (AUA) project of ProSPER.Net starts by reviewing existing models of recognition and appraisal of various aspects of HEIs’ work and aims at creating space for individual and collective reflection on HEI practices and outcomes. In addition to extensive consultations among ProSPER.Net members, as well as with other higher education actors and international organisations addressing higher education for sustainability, cross-sectoral consultations, assessments of the uncertainties and pertinent trends, and engagement with policy-making processes would be required for the AUA system to become a guiding force that shapes higher education of today and tomorrow.  相似文献   
3.
To assess the environmental impacts of large floating structures, various physical, chemical, and biological parameters were measured. The current and water quality were monitored around a prototype floating structure called the Phase-II Mega-Float model (MF-II model), which was moored off Yokosuka in Tokyo Bay during the period 1999–2000. The effects of the MF-II model on the condition of the physical environment, e.g., the direction and flow rate of water currents and the stratification structure, were negligible. Analysis of water quality showed that the concentrations of chlorophyll a and nutrients only varied just below the MF-II model. However, such variations were localized to within 5 m below the MF-II model since the waters were exchanged because of the tidal current. The minor changes in water quality are attributable to the impedance of photosynthesis due to the sea-covering effect and the activities of sessile organisms fouling the bottom surface of the MF-II model.  相似文献   
4.
Trace elements (22) and stable isotope ratios (δ15N and δ13C) were analyzed in marine organisms from shallow (SW) and deep-water (DW) of the East China Sea to understand biomagnification and prey source of trace elements. In the benthic marine organisms from DW, δ15N values were negatively correlated with Ba, Cu, Ag, Mo, Sr, As, and Co concentrations. This may be due to the specific accumulation in lower trophic animals and/or the biodilution through the food web in DW. Relationships between δ15N and concentrations of Co, Cr, Bi, and Tl in fish and Ag, Bi, V, Hg, and Tl in crustaceans showed positive correlations, suggesting that trophic position was affecting the concentrations of those elements in phyla, with higher trophic animals retaining higher concentrations than the lower trophic animals. Positive correlations between δ13C and Rb were observed in marine organisms. Therefore, Rb may be a possible substitute of δ13C as tracer of prey source in the East China Sea although further investigation is required.  相似文献   
5.
There is little information on vanadium (V) contamination in wildlife. In the present study, the mean V contents in liver and kidney from 41 wild Japanese water birds were less than 3.69 and 8.11 microg/g dry wt, respectively. The V contents in the liver and kidney of the spotbill duck were more than two times higher than those of other species in Japan. Spotbill ducks obtained in a residential district had a strong correlation between the V contents in the kidneys and those in the livers (R=0.924), and also between V and Ti, Cd, and Li contents in the liver (R>0.8). These results suggest that V accumulation in wild birds reflects the degree of environmental contamination.  相似文献   
6.
DNA damage is an important step in carcinogenesis. The Ames assay is a short-term screening of carcinogens that induce DNA damage. Most carcinogens require enzymatic activation through oxidation by cytochrome P450 (CYP450) in the presence of S9 mix. A combination of iron (Fe)(III) porphyrin and an oxidant is also able to oxidize compounds as an alternative metabolic pathway to CYP450. Previously it was reported that a chemical model containing a water-soluble 5,10,15,20-tetrakis(1-methylpyridinium4-yl)porphyrinatoiron(III) chloride (4-MPy) and tert-butyl hydroperoxide (t-BuOOH) activated aromatic amines and amides. In this study, a chemical model composed of an Fe porphyrin, water-insoluble 5,10,15,20-tetrakis(pentafluorophenyl)porphyrinatoiron(III) chloride (F5P) or water-soluble 4-MPy was optimized with an oxidant – t-BuOOH, magnesium monoperoxyphthalate (MPPT), or iodosylbenzene (PhIO). Subsequently the mutagenicity of benzo[a]pyrene (B[a]P) and chrysene in Salmonella typhimurium TA strains was compared. B[a]P was activated by a combination of F5P or 4-MPy plus MPPT or PhIO in S. typhimurium TA1538. The B[a]P-induced mutagenicity with F5P plus oxidant was higher than 4-MPy plus oxidant. Mutagenicity of chrysene, a tetracyclic aromatic hydrocarbon, was not detected in the presence of F5P/PhIO in S. typhimurium TA98, but was activated in the presence of F5P/MPPT. The F5P/MPPT activated other polyaromatic hydrocarbons (PAH) in the S. typhimurium TA98 assay including dibenz[a,c]anthracene, dibenz[a,h]anthracene, 3-methylcholanthrene, and benzo[a]anthracene. The results indicated that the F5P/MPPT was the most efficient model for detecting PAH-induced mutagenicity in the Ames assay.  相似文献   
7.
北京、东京、筑波大气中有机污染物组成研究   总被引:28,自引:0,他引:28  
用低流量采样器及双层采样滤膜 (石英及固相萃取用C1 8膜 )采集了北京、东京和筑波三城市冬季 (1999年 1月 )大气颗粒物和大气气相物质 ,3个城市的共同特点是大气气相物质中含有很高浓度的苯环数 2~ 4的多环芳烃及碳数小于 2 0的正构烷烃 ,大气颗粒物中以 5~ 6个苯环多环芳烃为主。冬季正构烷烃没有明显的偶数碳数和奇数的区别。但是 ,北京大气气相物质和颗粒物中多环芳烃浓度明显高于东京和筑波 ,而且各正构烷烃及多环芳烃的浓度分布也与东京和筑波的不同 ,表明冬季大气中有机污染物来源不同。   相似文献   
8.
9.
In this study, we investigated the behavior of estrogens in the rhizosphere of white clover (Trifolium repens, clover hereafter) with two different pot tests, using soil and agar as growth media. In a pot test using agar spiked with estrogen, the estrogen concentration in the agar with clover decreased to non-detectable levels within one month, while in the agar without clover, 60% of initially added estrogen remained after one month. The half-lives of estrone (E1) and 17β -estradiol (E2) in the agar with clover were 2.4–3.8 and 13.2 d, respectively. The dissipation of E1 followed first-order rate law, while that of E2 fitted a zero-order reaction, indicating that they had different mechanisms of dissipation from agar. In the soil pot test, the behavior of E1 and E2 was not influenced by clover. An initial rapid decrease in the amount of estrogen extracted by methanol/acetic acid was followed by persistence for 1–3 months, regardless of presence of clover. Moreover, in three weeks E1 and E2 were only partly degraded by microbes extracted from the soil used in the pot test. In this study, abiotic degradation of estrogens and sorption of estrogen to soil, rather than the effects of soil microbes and clover, contributed to the initial rapid dissipation of estrogens in the soil. However, the results of the agar pot test suggested that vegetation such as clover may significantly contribute to removal of estrogens when estrogens in aqueous phase are discharged with surface runoff and preferential flow after heavy rain in agricultural fields, or when present in soils with low estrogen sorptivity.  相似文献   
10.
Abstract

One of the thermal oxidation technologies recommended by the United Nations Environment Programme (UNEP) is destruction of chlorofluorocarbons (CFCs) in a cement kiln. The destruction of CFC12, CFC11 and CFC113 was studied in a cement kiln plant in actual commercial operation. CFCs were completely destroyed in the kiln under normal operating conditions. Hydrogen fluoride and hydrogen chloride generated by CFC decomposition were absorbed by cement materials. No formation of toxic ha-logenated organic compounds, such as polychlorinated dibenzo-p-dioxins or dibenzofurans (PCDDs/PCDFs), was observed in the CFC incineration.  相似文献   
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