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51.
Understanding neighbourhood conditions can play an important role in urban environmental management, especially when environmental services are lacking and new approachesare being debated. This paper describes and evaluates three research methods for assessing some of the environmentalproblems facing low income households and communities: (1) broad spectrum household surveys; (2) participatory rapid assessment; and (3) contingent valuation. As part of the study upon which this paper is based, the techniques were applied on a small scale in Jakarta. The paper finds that each technique can provide important and often complementaryinsights. The broad spectrum survey is particularly suitable to broad based planning, participatory appraisal to NGO initiatives and contingent valuation to utility pricing decisions.  相似文献   
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Mosaic trisomy 9 was detected in an amniotic fluid cell culture from a 40-year-old woman evaluated because of advanced maternal age. After counselling, parents elected to terminate the pregnancy. On autopsy the fetus was found to have hydrocephalus and a single kidney. The diagnosis of trisomy 9 mosaicism was confirmed in cultured skin fibroblasts. This is the third reported case of trisomy 9 mosaicism diagnosed prenatally.  相似文献   
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This paper investigates the impact of the recent criminalisation of humanitarian actors engaged in the search for and rescue of migrants in distress in the Mediterranean Sea, focusing on the impact on the motivation and engagement of humanitarian volunteers in Greece. It argues that criminalisation is aimed at reducing search and rescue (SAR) activities and thus removing perceived ‘pull factors’ for migrants. The paper locates this phenomenon within the broader trend of policing and punishing those who assist migrants in order to deter them and prevent others from engaging in such endeavours. It finds that efforts to criminalise can have the unintended effects of encouraging and mobilising volunteers, as well as generating public attention and support for migrants. However, the negative consequences of criminalisation are far-reaching, including contributing to a high mortality rate among those crossing the Mediterranean without SAR capabilities and the heightened risk of violence against migrants and those who help them.  相似文献   
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This paper reports the first investigation of risk perception by workers on offshore oil and gas installations on the UK Continental Shelf, following changes in offshore safety legislation in the wake of the Piper Alpha disaster in 1988. The Offshore Safety Case regulations (Health and Safety Executive, 1992, A Guide to the Offshore Installations (Safety Case) Regulations) put the onus on the operator to identify the major hazards and to reduce the risks to As Low As is Reasonably Practicable (ALARP). The regulations specifically state that Quantitative Risk Assessments (QRA) must be used when preparing the Safety Case. However, people do not use QRA when making everyday judgements about risk; they make subjective judgements known as risk perceptions, which are influenced by a number of different factors. This study was designed to complement the extensive QRA calculations that have already been carried out in the development of Safety Cases. The aim was to measure subjective risk perception in offshore personnel and examine how this relates to the more objective risk data available, namely accident records and QRA calculations. This paper describes the Offshore Risk Perception Questionnaire developed to collect the data and reports on UK offshore workers' perceptions of the risks associated with major and minor hazards, work tasks and other activities aboard production platforms.  相似文献   
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Contamination source identification is a crucial step in environmental remediation. The exact contaminant source locations and release histories are often unknown due to lack of records and therefore must be identified through inversion. Coupled source location and release history identification is a complex nonlinear optimization problem. Existing strategies for contaminant source identification have important practical limitations. In many studies, analytical solutions for point sources are used; the problem is often formulated and solved via nonlinear optimization; and model uncertainty is seldom considered. In practice, model uncertainty can be significant because of the uncertainty in model structure and parameters, and the error in numerical solutions. An inaccurate model can lead to erroneous inversion of contaminant sources. In this work, a constrained robust least squares (CRLS) estimator is combined with a branch-and-bound global optimization solver for iteratively identifying source release histories and source locations. CRLS is used for source release history recovery and the global optimization solver is used for location search. CRLS is a robust estimator that was developed to incorporate directly a modeler's prior knowledge of model uncertainty and measurement error. The robustness of CRLS is essential for systems that are ill-conditioned. Because of this decoupling, the total solution time can be reduced significantly. Our numerical experiments show that the combination of CRLS with the global optimization solver achieved better performance than the combination of a non-robust estimator, i.e., the nonnegative least squares (NNLS) method, with the same solver.  相似文献   
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The architecture and function of the lophophore of the marine bryozoan Cryptosula pallasiana (Moll) are described, including some new features not previously discovered in bryozoans. The nature of fluid movements within the lophophoral coelom during feeding activities is postulated on the basis of the arrangements of epithelia and muscles. Epithelial cells at the tentacle bases are blastemic in nature, and there is a ciliated pit of unknown function in the angle between every pair of tentacles. There are 6 nerves in each tentacle, including a pair of single-axon subperitoneal nerves. Neurosecretory-like vesicles and glycogen occur in some neurons of the ganglion. The basal lamina collagen has a diameter smaller than that previously recorded for an invertebrate. Filament dimensions are given for several different muscles. Tentacle muscles and lophophore retractor muscles are smooth. Thick paramyosin-like filaments up to 75 nm diameter occur in two muscle types. A new set of muscles is described: the basal transverse muscles of the tentacles.  相似文献   
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