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Predictive modelling to map subtidal communities is an alternative to “traditional” methods, such as direct sampling, remote sensing and acoustic survey, which are neither time- nor cost-effective for vast expanses. The principle of this modelling is the use of a combination of environmental key parameters to produce rules to understand species distribution and hence generate predictive maps. This study focuses on subtidal kelp forests (KF) on the coast of Brittany, France. The most significant key parameters to predict KF frequency are (1) the nature of the substrate, (2) depth, (3) water transparency, (4) water surface temperature and (5) hydrodynamics associated with the flexibility of algae in a flow. All these parameters are integrated in a spatial model, built using a Geographical Information System. This model results in a KF frequency map, where sites with optimum key parameters show a deeper limit of disappearance. After validation, the model is used in the context of Climate Change to estimate the effect of environmental variation on this depth limit of KF. Thus, the effects of both an increase in water temperature and a decrease in its transparency could lead to the complete disappearance of KF.  相似文献   
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Introduction  

To use biomarkers in monitoring programmes, potential confounding factors must be considered. In the clam Scrobicularia plana, the influence of size and salinity on biomarkers at different levels of biological organisation has been examined.  相似文献   
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Extrapolating across scales is a critical problem in ecology. Explicit mechanistic models of ecological systems provide a bridge from measurements of processes at small and short scales to larger scales; spatial patterns at large scales can be used to test the outcomes of these models. However, it is necessary to identify patterns that are not dependent on initial conditions, because small scale initial conditions will not normally be measured at large scales. We examined one possible pattern that could meet these conditions, the relationship between mean and variance in abundance of a parasitic tick in an individual based model of a lizard tick interaction. We scaled discrepancies between the observed and simulated patterns with a transformation of the variance–covariance matrix of the observed pattern to objectively identify patterns that are “close”.  相似文献   
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In its successful annual cycle of controversies and debates, the International Society of Prenatal Diagnosis and Therapy once again addressed non-invasive prenatal testing (NIPT) by following up on the 2013 controversy, ‘Should non-invasive DNA testing be the standard screening test for Down syndrome in all pregnant women’? with the proposition, ‘NIPT for chromosomel abnormalities should be offered to women with low a priori risk’. © 2014 John Wiley & Sons, Ltd.  相似文献   
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Tradable-permit schemes are becoming an increasingly popular technique for encouraging materials recovery and the diversion of waste from landfill. Such schemes operate using various forms of market-based trading of waste permits between polluters but usually rely on mandatory recycling targets to provide an incentive for trading. Using the UK's Packaging Recovery Note (PRN) scheme as a template, this paper examines the potential for permit trading where mandatory targets are absent and schemes must be driven solely by the financial benefits of reduced landfill costs and permit/material sales. The case examined is sterilized clinical waste, which has considerable recycling potential but suffers from health concerns and a poor public image. Interviews with healthcare and waste-management representatives indicate that although elements of the PRN scheme might prove appropriate for encouraging materials recovery, the absence of government targets and uncertain end markets for sterilized clinical waste present major obstacles to trading. Alternative incentives would therefore be required to catalyse schemes and develop recycling infrastructure. In the final analysis, thermal processing may be a more practical alternative to landfill than materials recovery for this particular waste stream.  相似文献   
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The goal to noninvasively detect fetal aneuploidies using circulating cell-free fetal DNA in the maternal plasma seems to be achieved by the use of massively parallel sequencing (MPS). To date, different MPS approaches exist, all aiming to deliver reliable results in a cost effective manner. The most widely used approach is the whole genome MPS method, in which sequencing is performed on maternal plasma to determine the presence of a fetal trisomy. To reduce costs targeted approaches, only analyzing loci from the chromosome(s) of interest has been developed. This review summarizes the different MPS approaches, their benefits and limitations and discusses the implications for future noninvasive prenatal testing. © 2013 John Wiley & Sons, Ltd.  相似文献   
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