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391.
Excessive heat is a health risk, yet previous studies have observed a general decline in sensitivity to heat despite increasing temperatures. Conclusive evidence is lacking on whether long-term changes of this sensitivity can be attributed to specific adaptation measures, such as air conditioning, or should be linked to societal adaptation, such as improved healthcare systems or socioeconomic well-being. The aim of this study was to assess the variation of the association between heat and daily mortality during summer in Japan since the 1970s and to examine the influence of air conditioning (AC) prevalence, healthcare resources, and socioeconomic developments at the prefecture level on this variation.We analyzed daily total, cardiovascular and respiratory disease mortality and temperature data from 1972 to 2010 for 47 prefectures. We used Poisson generalized linear model to estimate the effect of heat on mortality, random effects model to obtain the mean national effect estimates, and meta-regression to explore the impact of prefecture-level characteristics.Average summer temperature has increased across Japan during the 39-year period. Excess mortality attributable to summer heat has decreased, with a national reduction of 20 (95%CI: 17, 22), 21 (95%CI: 18, 25), and 46 (95%CI: 36, 55) cases of total, cardiovascular, and respiratory deaths (per 1000 deaths). The increase of AC prevalence was not associated with a reduction of excess mortality over time. Prefectures and populations with improved economic status documented a larger decline of excess mortality. Healthcare resources were associated with fewer heat-related deaths in the 1970s, but the associations did not persist in the more recent period (i.e., 2006–2010).Excess mortality due to heat has reduced in Japan, suggesting population adaptation. Yet, heat remains a significant health risk. Socioeconomic developments may play a role in heat adaptation. These findings may have implications for ensuring effective prevention of heat-related health impacts. 相似文献
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为了实现上海市房地产权的信息化管理,上海市房屋土地资源管理局建立了全市统一的集中式的房地产权籍管理信息系统。本文讨论如何实现权籍管理信息系统下的地籍变更,保持图形数据和属性数据的统一。 相似文献
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《Geoforum》2017
Weather modification operations are the intentional alteration of weather and cloud water conditions using technologies such as cloud seeding. Post-socialist authoritarian China is the world’s leading user of state power for rainfall enhancement through weather modification, with diverse purposes including agriculture production, water security, ecological preservation, and mega events. We argue that weather modification in China needs to be understood as a facet of ecological modernization, in which the authoritarian state believes that precipitation can be controlled through the use of advanced technologies, thus transforming clouds into a kind of cloud water resource. Two political dimensions are highlighted to understand precipitation control and utilization of cloud water: the first is a new ideological politics of the changing human-weather relationship from ‘adaptation to the weather’ to ‘taming the weather”; the second is volume politics that presents unique characteristics of airborne water as opposed to terrestrial and groundwater. 相似文献
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三峡水库蓄水运用后,城汉河段悬移质输沙量大幅度减少,推移质输沙量所占比重增加,造床作用日益凸显,故开展其推移质输沙率计算公式研究具有理论与实际意义。利用螺山和汉口水文站实测资料建立了推移质输沙率与流量之间的指数关系式,并据此推算了两站逐日推移质输沙率,结果表明:螺山站、汉口站输沙率均与流量的0.912 78次方成正比,多年(2009—2015年)平均推移质输沙量分别为137万t、152万t,主要集中在汛期。利用推移质实测资料对Engelund、Einstein、Yalin 3个公式进行了检验与修正,结果表明:修正前各公式计算结果比较分散,且与实测值偏差很大;修正后各公式计算精度显著提高,综合比较发现,修正后的Yalin公式精度最高,Engelund公式、指数关系式次之,Einstein公式精度相对较低。因此,修正后的Yalin公式更适合于城汉河段推移质输沙率计算,可用于该河段的演变分析与数学模型计算。 相似文献
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矿床是复杂地质作用的结果.矿床形成后又经历不同形式和不同程度的变化.由于已发现矿床的大多数是在其形成后经过变化而保存下来的, 因此矿床学研究应兼顾矿床的形成(成因) 和矿床的变化、保存(产出) 两个方面, 以提高矿产预测的能力.矿床变化与保存的研究内容包括: (1) 控制要素; (2) 变化、改造的过程; (3) 变化、改造的产物; (4) 不同矿床类型的变化; (5) 不同时-空域中矿床的变化; (6) 矿床保存条件.研究成矿后变化的基本方法有: 地质构造制图、地球化学分析和模拟实验.提出要研究和建立矿床的变化、改造模型; 将矿床演变作为含矿区域地质历史的一个环节, 将矿床个体变化研究与区域成矿系统演变相结合.矿床变化研究既有利于矿产预测和勘查, 又可为改善矿区和区域生态环境提供基础资料. 相似文献