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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   
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Stable isotope ratios of hydrogen and oxygen of water are useful tracers of the hydrological cycle. For example, isotopes monitor the evapotranspiration in vegetated areas, local snow ice processes and stream water flow processes. δ18O and δD in rainwater reflect the processes of evaporation, condensation and precipitation. Heavy rains thus modify the stable isotope ratio of ground water, stream water and transpiration water vapor. However, the controlling factors of δ18O and δD are not clear. Here we analyzed the inorganic ion concentration and stable isotope ratio in 38 normal rainwater and 15 heavy rainwater samples were collected in Shinjuku, Tokyo, Japan, during four years from October 2012 to December 2015. Results show a decrease in δ18O and δD values with the total rainfall amount, thus highlighting the amount effect. δ18O and δD volume-weighted mean values in typhoon heavy rain were higher than the values estimated from amount effect, whereas δ18O and δD volume-weighted mean values in urban-induced heavy rain were lower. Typhoon heavy rain has high Na+ ratio and stable isotope ratios, while urban-induced heavy rain has low Na+ ratio and stable isotope ratio.  相似文献   
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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   
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To study atmospheric mercury absorption in human respiratory passage-ways, mercury in expired air was measured in three different states of breathing: steady breathing, deep breathing and breath held after inspiration.In this study, air containing mercury was inhaled through the nose and expired through the mouth. The concentration of mercury in the exhaled air was determined by the technique of gold-amalgam trapping, heat vaporization, and flameless atomic absorption measurement.The subjects were 13 male adults, aged 25–62 years, and 38 cases were observed. Four different concentrations of mercury, 1–3, 4–6, 10–11, and 20–30 μg/m3 were used, and absorption for each was determined. When the concentration was 1–3 μg/m3, the absorption was 74–92%, the average being 82.5%. At concentrations of 4–6, 10–11, and 20–30 μg/m3, the absorption was 76.6–100%, 75.5–99.2%, and 79.9–95.9% respectively, and the average was 88.8%, 85.2%, and 87.7% respectively.A slightly higher rate of mercury absorption was observed in deep breathing than in steady breathing, and when expiration was suppressed for some time after inspiration, the rate increased remarkably to 97.4–99.7%. Prolonged retention of inhaled air containing mercury in the respiratory tract is believed to have caused the increased absorption.  相似文献   
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To understand which soil chemical properties are the best predictors of CH4 production in rice paddy soils, a model was developed with empirical data from nine types of rice soils collected around Japan and anaerobically incubated at 30 degrees C for 16 wk in laboratory conditions. After 1, 2, 4, 8, and 16 wk of incubation, CO2, CH4, and Fe(II) were measured to understand soil organic matter decomposition and iron (Fe) reduction. Available N (N ava) was also measured at the end of incubation. The results showed that decomposable C and reducible Fe are two key parameters that regulate soil CH(4) production (P CH4). There was a significant relationship between decomposable C and available N (N ava) (r2 = 0.975**). Except for a sandy soil sample, a significant relationship between total Fe (Fe total) and reducible Fe was found. From this experiment, a simple model of soil CH4 production was developed: P CH4 = 1.593N(ava) - 2.460Fe total/1000 (each unit was mg kg(-1) soil). After simulated CH4 production by two soil chemical properties as above, there was a significant consistency between model simulation and actual measurement (r2 = 0.831**).  相似文献   
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To learn more about the biodegradation of potassium bromate, the decomposition of bromate in various tissues of rats was studied. Bromate was degraded very slowly in human saliva and plasma of rat. However, nearly all tissue homogenates and red blood cells could degrade bromate by a mechanism which exhibited some stability to heat. Furthermore, it was suggested that the bromate degradation active component in the supernatant fraction of a liver homogenate was in part glutathione.  相似文献   
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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   
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