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111.
Environmental and Ecological Statistics - A non-homogeneous Poisson process is used to study the rate at which a pollutant’s concentration exceeds a given threshold of interest. An...  相似文献   
112.
Environmental Geochemistry and Health - Biochar (BC) is a porous, carbonaceous material produced by slow pyrolysis of biomass under oxygen-limited conditions. BC production has been attracting...  相似文献   
113.
If sustainability science is to mature as a discipline, it will be important for practitioners to discuss and eventually agree upon the fundamentals of the paradigm on which the new discipline is based. Since sustainability is fundamentally a normative assertion about tradeoffs among values, how society chooses the specifics among these tradeoffs is central to the sustainability problem. Whose values should count in making social decisions and how should the multiplicity of values that exist be known and used in that decision process? Given the vast spatial domains and temporal domains at work in the sustainability problem, we need some means of reconciling the inevitably divergent choices depending on whose values we count, how we know what those values are, and how we count them in making social decisions. We propose an approach to dealing with these questions based on Rawls (A theory of justice. Belknap Press, Cambridge, 1971) and explore the problems inherent in a social choice theory for sustainability science.  相似文献   
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This paper analyses the relationship between nitrous oxide (N2O) emissions, economic growth, agricultural land used and exports in Germany. We use time‐series data between 1970 and 2012 and the Autoregressive Distributed Lag (ARDL) methodology to test for cointegration in the long run. Results show that there is a quadratic long run relationship between N2O emissions and economic growth, confirming the existence of an Environmental Kuznets Curve (EKC) for Germany. Agricultural land area affects N2O emissions positively, whereas exports affect emissions negatively. The turning point is $27,880, which is within the sample and implies that Germany is in the decreasing part of the curve of environmental degradation. The paper shows that, contrary to testing the EKC in less developed countries, mitigation of N2O emissions does not negatively affect growth in Germany. As such, it is feasible to undertake any conservative policy in order to reduce emissions without major consequences on economic sectors.  相似文献   
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A retrospective cohort study was performed in five Italian obstetrical centres from 1984 to 1991 in order to verify the association between chorionic villus sampling (CVS) and transverse limb reduction defects (TLRDs). TLRD rates by period of gestation at CVS were calculated, and the study's results were compared with data from the general population. Of the 3430 pregnancies for which CVS was performed, 2759 had a known outcome. The overall rate for TLRDs was 1 in 1143 CVS pregnancies, four times higher than that of the general population in Italy (1 in 4458). The rate of TLRDs was 2·9/1000 for CVS performed at 9 weeks' gestation and 1·0/1000 for CVS at 10 weeks' gestation. A scalp defect was detected in a pregnancy in which CVS was performed at 10 weeks. A high proportion of pregnancies lost to follow-up and the poor quality of the data may have affected the results. Nevertheless, our results suggest an association between CVS carried out at less than 10 weeks' gestation and TLRDs which is consistent with the findings of other studies. CVS should not be prepared at less than 10 weeks' gestation until additional evidence is obtained.  相似文献   
118.
A prenatal diagnosis of campomelic dysplasia in a primigravida is described. First level fetal ultrasonography demonstrated bowing and shortening of lower limbs. Second level examination allowed the correct diagnosis by demonstrating several skeletal anomalies pathognomonic of campomelic dysplasia.  相似文献   
119.
本文从三个方面论述了保护原则的应用与转基因生物(GMOs)的调控之间的关系:①在应用保护原则时所出现的随意性,反映了一个更深层次的问题,即影响可持续性科学分析的认识论,需要我们区分"风险(risk)"、"不确定性(uncertainty)"和"无知(ignorance)"三个概念之间的差异;②在讨论进化这一科学问题时,我们不可能完全避免不确定性和无知,因此,就难以使用传统的风险分析方法(概率分布分析和精确的数值模拟),而应当选取来自其他科学领域(生态学一般原则或者隐喻)的替代方法;③生态风险的存在,不应当作为完全停止创新的理由,但保护原则的使用,可以使科学家们的理念从"存在合理性"(substantive rationality)(试图给出社会的最优化解决办法),转变到"过程合理性"(procedural rationality)(试图帮助社会找出"令人满意的"解决办法).  相似文献   
120.
Literature shows that full-scale pure-oxygen activated sludge (O2-AS) wastewater treatment plants (WWTPs) generate effluents with higher dissolved-organic carbon (DOC) concentrations and larger high-molecular-weight fractions compared to air-activated-sludge (Air-AS) WWTP effluents. The purpose of this paper was to evaluate how gas supplied (air vs. pure oxygen) to sequencing-batch reactors affected DOC transformations. The main conclusions of this paper are (a) O2-AS effluent DOC is more refractory than air-AS effluent DOC; and (b) O2-AS systems may have higher five-day biochemical oxygen demand removals than air-AS systems; however, in terms of COD and DOC removal, air-AS systems are better than O2-AS systems. Analysis of a database from side-by-side O2- and air-AS pilot tests from literature supported these observations.  相似文献   
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