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571.
572.
We report two cases in the same family of progressive neuronal degeneration of childhood—Alpers syndrome—with prenatal MRI findings in one case. The first infant presented at birth with severe microcephaly, then rapidly evolved to progressive encephalopathy with refractory epilepsy, leading to death at 10 months. Biochemical investigations including liver function tests were normal. CT and MRI showed severe diffuse brain atrophy. The diagnosis of progressive neuronal degeneration of childhood was made on the clinical and imaging data. The second pregnancy was marked by gradual decrease of fetal cerebral biometry and a prenatal MRI performed at 32 weeks showed diffuse cortical atrophy, as observed in the sibling. The infant died at 5 months. Neuropathological findings were consistent with Alpers syndrome. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
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We measured the clearance rates of the filter-feeding bivalve Corbicula fluminea over a period of 2?years. Strong seasonal variations, such as a 50-fold increase from February to July, were observed. These variations were only poorly linked to temperature, as they could be found at both the ambient field temperature and a constant temperature of 15°C. Instead, peaks in the filtration activity corresponded to the spawning activity. Additionally, a strong interannual variability with much lower clearance rates in 2009 than in 2008 was identified. The low clearance rates were linked to a preceding period of low winter temperatures close to the lethal temperature of 2°C and the associated reduced reproduction rates. Our findings demonstrate that other factors besides temperature and body mass can strongly affect clearance rates. These results should be considered when predicting the effects of changing temperatures on the ecosystem impact of filter-feeding bivalves.  相似文献   
575.
This paper describes a preliminary evaluation of the performance of carbonaceous materials prepared from sewage sludges (SBCMs) in a hybrid water treatment process based on adsorption and catalytic wet air oxidation; phenol was used as the model pollutant. Three different sewage sludges were treated by either carbonisation or steam activation, and the physico-chemical properties of the resultant carbonaceous materials (e.g. hardness, BET surface area, ash and elemental content, surface chemistry) were evaluated and compared with a commercial reference activated carbon (PICA F22). The adsorption capacity for phenol of the SBCMs was greater than suggested by their BET surface area, but less than F22; a steam activated, dewatered raw sludge (SA_DRAW) had the greatest adsorption capacity of the SBCMs in the investigated range of concentrations (<0.05 mol L?1). In batch oxidation tests, the SBCMs demonstrated catalytic behaviour arising from their substrate adsorptivity and metal content. Recycling of SA_DRAW in successive oxidations led to significant structural attrition and a hardened SA_DRAW was evaluated, but found to be unsatisfactory during the oxidation step. In a combined adsorption–oxidation sequence, both the PICA carbon and a selected SBCM showed deterioration in phenol adsorption after oxidative regeneration, but a steady state performance was reached after 2 or 3 cycles.  相似文献   
576.
The ability to pay for water and wastewater services is a growing issue in the developed world. To this point in time, utilities have helped customers grappling with affordability issues using different types of customer assistance programs (CAPs). Income‐based billing approaches differ from CAPs in that bills are structured so as to be affordable for customers at the outset. Recently, the City of Philadelphia implemented an innovative program to work towards resolving the affordability problem in their city using income‐based billing. This tiered assistance program or TAP structures bills for water, wastewater, and stormwater services to program enrollees’ income. Given the innovative nature of the program, this paper describes the rollout of TAP and assesses the impact of the program on customers and utility revenues. The paper closes with a critical assessment of TAP and considerations for utilities evaluating the implementation of similar programs.  相似文献   
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Climate change has the potential to compromise the sustainability of natural resources in Mediterranean climatic systems, such that short-term reactive responses will increasingly be insufficient to ensure effective management. There is a simultaneous need for both the clear articulation of the vulnerabilities of specific management systems to climate risk, and the development of appropriate short- and long-term strategic planning responses that anticipate environmental change or allow for sustainable adaptive management in response to trends in resource condition. Governments are developing climate change adaptation policy frameworks, but without the recognition of the importance of responding strategically, regional stakeholders will struggle to manage future climate risk. In a partnership between the South Australian Government, the Adelaide and Mt Lofty Ranges Natural Resource Management Board and the regional community, a range of available research approaches to support regional climate change adaptation decision-making, were applied and critically examined, including: scenario modelling; applied and participatory Geographical Information Systems modelling; environmental risk analysis; and participatory action learning. As managers apply ideas for adaptation within their own biophysical and socio-cultural contexts, there would be both successes and failures, but a learning orientation to societal change will enable improvements over time. A base-line target for regional responses to climate change is the ownership of the issue by stakeholders, which leads to an acceptance that effective actions to adapt are now both possible and vitally important. Beyond such baseline knowledge, the research suggests that there is a range of tools from the social and physical sciences available to guide adaptation decision-making.  相似文献   
579.
This article provides a critical review of the environmental chemistry of inorganic antimony (Sb) in soils, comparing and contrasting findings with those of arsenic (As). Characteristics of the Sb soil system are reviewed, with an emphasis on speciation, sorption and phase associations, identifying differences between Sb and As behaviour. Knowledge gaps in environmentally relevant Sb data for soils are identified and discussed in terms of the limitations this imposes on understanding the fate, behaviour and risks associated with Sb in environmental soil systems, with particular reference to mobility and bioavailability.  相似文献   
580.
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