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51.
The sirenomelia sequence with fusion, rotation, hypotrophy or atrophy of the lower limbs in combination with severe urogenital and gastrointestinal malformations is a rare and usually lethal disorder. We present the case of a 28-year-old woman, who was referred to our department because of an intraabdominal cystic structure in the 9th week of gestation. Subsequent scans confirmed the diagnosis of a sirenomelia sequence with the fusion of the lower extremities without fusion of the bones according to Stocker I classification. The size of the intraabdominal cyst decreased during follow-up. After counseling, termination of pregnancy was induced. The postmortem X-ray confirmed the ultrasound diagnosis. The exact etiological mechanism of this malformation is still unknown. An early alteration of the embryological vascular network damaging the caudal mesoderm is thought to lead to arrested development of the lower limbs and other affected organs. The cyst we saw in the 9th week might fit with this theory, either as an expression of the complex malformation of the lower abdomen or as the sonographic appearance of necrosis. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
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Heterogeneous photocatalytic oxidation is a water reclamation technology which avoids chemical consumption and can be powered by solar radiation. Because this generally sustainable process is of limited efficiency for the treatment of biologically pretreated greywater, it was combined with activated carbon adsorption. The effluent of a constructed wetland for treatment of separately collected greywater was subjected to photocatalytic oxidation using the photocatalyst titanium dioxide (TiO2) “P25” in both the absence and the presence of powdered activated carbon (PAC). Photocatalytic oxidation alone with UV fluences of about 10 Wh L?1 was not capable of reducing total organic carbon (TOC) from an initial concentration of 5.5 mg L?1 safely below 2 mg L?1 as a prerequisite for high-quality water reuse purposes. However, when PAC was added, TOC concentrations subsequent to photocatalytic oxidation were less than 2 mg L?1 even after reusing the TiO2/PAC mixture 10 times. PAC addition is estimated to reduce the insolation area necessary to achieve this target by solar photocatalytic oxidation of biologically treated greywater by a factor 7. This combination process represents an innovative chemical-free technology within wastewater reuse schemes.  相似文献   
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Studies on personal dust and endotoxin concentrations among animal farmers have been either small or limited to a few sectors in their investigations. The present study aimed to provide comparable information on the levels and variability of exposure to personal dust and endotoxin in different types of animal farmers. 507 personal inhalable dust samples were collected from 327 farmers employed in 54 pig, 26 dairy, 3 poultry, and 3 mink farms in Denmark. Measurements in pig and dairy farmers were full-shift and performed during summer and winter, while poultry and mink farmers were monitored during 4 well-defined production stages. The collected samples were measured for dust gravimetrically and analyzed for endotoxin by the Limulus amebocyte lysate assay. Simple statistics and random-effect analysis were used to describe the levels and the variability in measured dust and endotoxin exposure concentrations. Measured inhalable dust levels had an overall geometric mean of 2.5 mg m(-3) (range 相似文献   
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Rapid environmental degradation in China makes understanding how perceived exposure to environmental harm influences environmental attitudes and participation in pro-environmental behaviors among the Chinese people crucial. We used a nation-wide survey dataset in urban China to test two hypotheses: experiencing environmental harm directly affects environmental behavior; environmental attitudes mediate the relationship between experiencing environmental harm and environmental behavior. We found respondents who experienced environmental harm had more pro-environmental attitudes. Experiencing environmental harm positively influenced pro-environmental behavior both directly and indirectly through the mediation of pro-environmental attitudes. Among the pro-environmental behaviors, environmental litigation was most strongly related with exposure to environmental harm. Our results suggest that more participation in pro-environmental behaviors may be expected as rapid economic development increases public exposure to environmental harm in urban China.  相似文献   
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Recently developed theoretical models of stage-structured consumer-resource systems have shown that stage-specific biomass overcompensation can arise in response to increased mortality rates. We parameterized a stage-structured population model to simulate the effects of increased adult mortality caused by a pathogen outbreak in the perch (Perca fluviatilis) population of Windermere (UK) in 1976. The model predicts biomass overcompensation by juveniles in response to increased adult mortality due to a shift in food-dependent growth and reproduction rates. Considering cannibalism between life stages in the model reinforces this compensatory response due to the release from predation on juveniles at high mortality rates. These model predictions are matched by our analysis of a 60-year time series of scientific monitoring of Windermere perch, which shows that the pathogen outbreak induced a strong decrease in adult biomass and a corresponding increase in juvenile biomass. Age-specific adult fecundity and size at age were higher after than before the disease outbreak, suggesting that the pathogen-induced mortality released adult perch from competition, thereby increasing somatic and reproductive growth. Higher juvenile survival after the pathogen outbreak due to a release from cannibalism likely contributed to the observed biomass overcompensation. Our findings have general implications for predicting population- and community-level responses to increased size-selective mortality caused by exploitation or disease outbreaks.  相似文献   
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Transdisciplinary research and collaboration is widely acknowledged as a critical success factor for solution-oriented approaches that can tackle complex sustainability challenges, such as biodiversity loss, pollution, and climate-related hazards. In this context, city governments’ engagement in transdisciplinarity is generally seen as a key condition for societal transformation towards sustainability. However, empirical evidence is rare. This paper presents a self-assessment of a joint research project on ecosystem services and climate adaptation planning (ECOSIMP) undertaken by four universities and seven Swedish municipalities. We apply a set of design principles and guiding questions for transdisciplinary sustainability projects and, on this basis, identify key aspects for supporting university–municipality collaboration. We show that: (1) selecting the number and type of project stakeholders requires more explicit consideration of the purpose of societal actors’ participation; (2) concrete, interim benefits for participating practitioners and organisations need to be continuously discussed; (3) promoting the ‘inter’, i.e., interdisciplinary and inter-city learning, can support transdisciplinarity and, ultimately, urban sustainability and long-term change. In this context, we found that design principles for transdisciplinarity have the potential to (4) mitigate project shortcomings, even when transdisciplinarity is not an explicit aim, and (5) address differences and allow new voices to be heard. We propose additional guiding questions to address shortcomings and inspire reflexivity in transdisciplinary projects.  相似文献   
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Olsen GR  Carstensen N  Høyen K 《Disasters》2003,27(2):109-126
This paper proposes a basic hypothesis that the volume of emergency assistance any humanitarian crisis attracts is determined by three main factors working either in conjunction or individually. First, it depends on the intensity of media coverage. Second, it depends on the degree of political interest, particularly related to security, that donor governments have in a particular region. Third, the volume of emergency aid depends on strength of humanitarian NGOs and international organisations present in a specific country experiencing a humanitarian emergency. The empirical analysis of a number of emergency situations is carried out based on material that has never been published before. The paper concludes that only occasionally do the media play a decisive role in influencing donors. Rather, the security interests of Western donors are important together with the presence and strength of humanitarian stakeholders, such as NGOs and international organisations lobbying donor governments.  相似文献   
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