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101.
In vivo exposure of rats to 10 ppm nitrogen dioxide (NO2) for 12h caused changes in fatty acids composition of alveolar lavage phospholipids. Among the fatty acid species, the relative ratio of palmitic acid, myristic acid and palmitoleic acid increased significantly. While the relative ratio of stearic acid, oleic acid, linoleic acid and arachidonic acid decreased significantly. Both the increase in the incorporation of palmitic acid in phosphatidylcholine which would be released into the alveoli and the increase in the release of phosphatidylcholine into the alveoli may account for the changes in the fatty acid composition of the present findings.  相似文献   
102.
Climate change adaptation practices of apple growers in Nagano, Japan   总被引:1,自引:0,他引:1  
By an interview survey with apple growers in Nagano Prefecture, Japan, we found that their recognition of and reaction to climate change depends on their sales channels. Against rising air temperature, more farmers on direct sales (Type D farmers) than those on sales via the markets (Type M farmers) recognized the delay in fruit maturity as the effect of climate change, specifically temperature rise, (Type D: 62%, Type M: 15%). In response to the delay in maturity, Type D farmers simply delayed the harvest to full maturity by about 10 days than they did 20 years ago. On the other hand, Type M farmers recognized delayed reddening of the fruits as the most salient result of climate change (Type D: 8%, Type M: 46%), and took measures to accelerate the coloring by placing reflective materials on ground and/or picking off leaves around the fruits. The contrasting behaviors can be explained by the difference in the critical trait of the products. For Type M farmers, timing of the shipment is critical to avoid competition with shipments from other apple growing areas, and the good coloring is the prerequisite for the shipment. For Type D farmers, by contrast, full maturity is more important than coloring, since their contract with the customers hinges on the palatability of the fruits rather than the timing. This study has thus identified positioning of the farmers with the sales channel as a determinant in their adaptation behavior and vulnerability to climatic changes.  相似文献   
103.
挥发性氯代烃在干燥土壤中的平衡吸附研究   总被引:1,自引:1,他引:0  
孟凡勇  刘锐  小林刚  万梅  余素林  陈吕军 《环境科学》2011,32(10):3121-3127
吸附是挥发性氯代烃(volatile chlorinated hydrocarbons,VCHs)污染土壤的主要机制之一.采集长三角地区3类典型水稻土,用静态平衡吸附实验进行干燥土壤对6种VCHs的平衡吸附研究.结果表明,干燥土壤的平衡吸附等温线难以用Langmuir方程和BET方程描述,但用Dubinin-Astak...  相似文献   
104.
开放式臭氧浓度升高对2个冬小麦品种光合损伤的研究   总被引:11,自引:5,他引:6  
在开放式臭氧浓度升高(ozone-free air controlled enrichment,O3-FACE)平台上,观测了高浓度臭氧(正常大气臭氧浓度的基础上增加50%)对2个冬小麦(Tritcium aestivum L.)品种(烟农19和扬麦16)在灌浆期内功能叶片光合损伤的情况.观测显示,整个灌浆期内2个小麦品种有关参数响应的趋势表现一致:①净光合速率(Pn)逐渐下降,在臭氧处理35 d时,烟农19和扬麦16降幅分别达到56.21%和21.82%.②荧光动力学参数Fv/Fm(最大光化学量子产量)、qp(光化学淬灭系数)、Φexc(PSⅡ有效光化学量子产量)、ΦPSⅡ(PSⅡ实际光化学量子产量)呈下降趋势,NPQ(非光化学淬灭系数)逐渐上升;在能量分配方面,吸收的光能在PSⅡ天线色素的耗散部分(%D)升高、用于PSⅡ光化学反应的部分(%P)降低,而不属于前两者的其它消耗部分(%X)变化不明显.在臭氧处理35 d时,烟农19和扬麦16的ΦPSⅡ分别下降24.42%和9.97%.③光合色素参数Chla/Chlb(叶绿素a/叶绿素b)比值上升,而Chlt/Car(叶绿素/叶黄素)的比值下降.④叶绿体内依赖Mg2+、Ca2+的ATPase(ATP酶)活性和ATP含量均增加.上述参数随臭氧处理时间延长,变化幅度和品种间的差异趋于显著,当臭氧处理35 d时,变幅最大,且烟农19变幅显著大于扬麦16.结果表明,在臭氧浓度升高环境下,作物通过增加热耗散、改变色素含量和结构、提高ATPase活性等进行防御和损伤修复.随着处理时间的增加,臭氧对冬小麦的光合损伤具有累积效应,且2个品种表现出较大的差异性.  相似文献   
105.
Most of the statistical techniques used to evaluate the data obtained from toxicity studies are based on the assumption that the data show a normal distribution and homogeneity of variance. Literature review on toxicity studies on laboratory animals reveals that in most of the cases homogeneity of variance alone is examined for the data obtained from these studies. But the data that show homogeneity of variance need not always show a normal distribution. In fact, most of the data derived from toxicity studies, including hematological and biochemical parameters show a non-normal distribution. On examining normality of data obtained from various toxicity studies using different normality tests, we observed that Shapiro-Wilk test is more appropriate than Kolmogorov-Smimov test, Lilliefors test, the normal probability paper analysis and Chi square test. But there are situations, especially in the long-term toxicity studies, where normality is not shown by one or more than one of the dosage groups. In this situation, we propose that the data maybe analyzed using Dunnett multiple comparison test after excluding the data of the groups that do not show normality However, the biological relevance of the excluded data has to be carefully scrutinized. We also observed that the tendency of the data to show a normal distribution seems to be related to the age of the animals. Present paper describes various tests commonly used to test normality and their power, and also emphasizes the need of subjecting the data obtained from toxicity studies to both normality and homogeneity tests. A flow chart suggesting the statistical techniques that maybe used for both the types of data showing a normal or non-normal distribution is also proposed.  相似文献   
106.
In order to develop effective conservation strategies for endangered migratory species, the link between feeding and breeding grounds needs to be clarified. In this study, the genetic compositions of consecutive Japanese feeding aggregations of green turtles (Chelonia mydas) along the Kuroshio Current were examined by mixed-stock analyses of mitochondrial DNA control-region sequences. The results indicated that the southern feeding aggregation around Yaeyama (24.3°N, 124.0°E) was sourced from various Pacific rookeries in the Yaeyama, Ogasawara, Western Pacific, and Indian Oceans and Southeast Asia. Among northern feeding aggregations, the Ginoza (26.5°N, 128.0°E) aggregation was also sourced from the Western Pacific Ocean, but the Nomaike (31.4°N, 130.1°E), Muroto (33.2°N, 134.2°E), and Kanto (35.6°N, 140.5°E) aggregations were contributed mostly by the closer Ogasawara rookeries. The reduced contribution from tropical Pacific rookeries to northern feeding aggregations and the significant correlation between genetic differentiation and geographical distance matrices of feeding aggregations indicated that most hatchlings from these regions transported by the Kuroshio Current settle in upstream feeding grounds along the Japanese archipelago, implying that current flow influences the composition of feeding aggregations. Differences in the composition of relatively close neritic feeding aggregations have important conservation implications, for which both regional and multinational conservation strategies are needed.  相似文献   
107.
Urban tinkering     
Cities are currently experiencing serious, multifaceted impacts from global environmental change, especially climate change, and the degree to which they will need to cope with and adapt to such challenges will continue to increase. A complex systems approach inspired by evolutionary theory can inform strategies for policies and interventions to deal with growing urban vulnerabilities. Such an approach would guide the design of new (and redesign of existing) urban structures, while promoting innovative integration of grey, green and blue infrastructure in service of environmental and health objectives. Moreover, it would contribute to more flexible, effective policies for urban management and the use of urban space. Four decades ago, in a seminal paper in Science, the French evolutionary biologist and philosopher Francois Jacob noted that evolution differs significantly in its characteristic modes of action from processes that are designed and engineered de novo (Jacob in Science 196(4295):1161–1166, 1977). He labeled the evolutionary process “tinkering”, recognizing its foundation in the modification and molding of existing traits and forms, with occasional dramatic shifts in function in the context of changing conditions. This contrasts greatly with conventional engineering and design approaches that apply tailor-made materials and tools to achieve well-defined functions that are specified a priori. We here propose that urban tinkering is the application of evolutionary thinking to urban design, engineering, ecological restoration, management and governance. We define urban tinkering as:
A mode of operation, encompassing policy, planning and management processes, that seeks to transform the use of existing and design of new urban systems in ways that diversify their functions, anticipate new uses and enhance adaptability, to better meet the social, economic and ecological needs of cities under conditions of deep uncertainty about the future.
This approach has the potential to substantially complement and augment conventional urban development, replacing predictability, linearity and monofunctional design with anticipation of uncertainty and non-linearity and design for multiple, potentially shifting functions. Urban tinkering can function by promoting a diversity of small-scale urban experiments that, in aggregate, lead to large-scale often playful innovative solutions to the problems of sustainable development. Moreover, the tinkering approach is naturally suited to exploring multi-functional uses and approaches (e.g., bricolage) for new and existing urban structures and policies through collaborative engagement and analysis. It is thus well worth exploring as a means of delivering co-benefits for environment and human health and wellbeing. Indeed, urban tinkering has close ties to systems approaches, which often are recognized as critical to sustainable development. We believe this concept can help forge much-closer, much-needed ties among engineers, architects, evolutionary ecologists, health specialists, and numerous other urban stakeholders in developing innovative, widely beneficial solutions for society and contribute to successful implementation of SDG11 and the New Urban Agenda.
  相似文献   
108.
Present trends of urbanization are accompanied by increasing demographic and economic shrinkage of rural regions. In countries such as Japan, these rural regions trail behind metropolitan counterparts according to GDP, the conventional measure used to guide governmental policies. Yet, past research suggests that these regions may be undervalued. Further, the Inclusive Wealth Index (IWI), largely only used at the national level, may be able to capture aspects previously missed. As such, our study attempts to highlight the wealth of rural regions by comparing the inclusive wealth of Sado Island and Japan between 1990 and 2014. Minor methodological modifications were made according to data availability at the local level and to improve the accuracy of human capital estimations. Results captured the ongoing shrinkage of Sado and demonstrate the distinct potential of the IWI as a stock measure. Sado’s per capita wealth was about 10% lower than the national averages, but its natural capital was about threefold national averages. Supplementary estimations of the natural capital of fisheries and cultivated forests suggest that inclusion of additional factors in the evaluation would further increase the relative valuation of rural regions. We discuss implications of our estimations for wellbeing, and conclude with a critical appraisal of the IWI calculation towards policy implementation of the index.  相似文献   
109.
Time trend of hexabromocyclododecane in the breast milk of Japanese women   总被引:1,自引:0,他引:1  
Kakimoto K  Akutsu K  Konishi Y  Tanaka Y 《Chemosphere》2008,71(6):1110-1114
Hexabromocyclododecane (HBCD) is a type of brominated flame retardant. We investigated the time trend of the stereoisomer-specific concentrations of HBCD (alpha, beta, and gamma) in breast milk samples of Japanese women by using liquid chromatography-tandem mass spectrometry (LC/MS/MS). The pooled milk lipid samples collected in 1973, 1978, 1983, 1988, 1993, 1999, and from 2000 to 2006 were analysed. The concentration was below the detection limit in the samples collected between 1973 and 1983 and increased in those collected since 1988. Between 1988 and 2006, alpha-HBCD was detected in all 11 breast milk samples collected from 25 to 29-year-old Japanese women; gamma-HBCD, in 7; and beta-HBCD, in none of the samples. Time trend of summation operatorHBCD appeared to be related to that of the industrial HBCD consumption level in Japan.  相似文献   
110.
In order to understand the long-term behaviors of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), pentachlorophenol (PCP), and 2,4,6-trichlorophenyl-4′-nitrophenyl ether (chlornitrofen, CNP) in paddy soil, we measured their concentrations in paddy soil samples collected in 1982 and 1984 (1980s) and in 2000 and 2002 (2000s) from the Yoneshiro River basin, Japan. The concentrations of PCP and CNP decreased from the 1980s to the 2000s, whereas the concentrations of PCDD/Fs and their toxic equivalency (WHO2006-TEQ) remained. The major sources of PCDD/Fs in the paddy soil samples were attributed to impurities in PCP and CNP as a result of comparisons of homologue and congener profiles and principal component analysis. Based on the results of comparison of total input and remaining amount, it is estimated that more than 99% of PCP and CNP applied to the paddy fields had disappeared, whereas most of the applied PCDD/Fs and TEQ remained.  相似文献   
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