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The urban solid waste of the city of Indaiatuba (pop. 175 000), located in the state of S?o Paulo, was characterized, focusing on the recycling potential. For this purpose, collected waste was subdivided into 27 items, classified by mass and volume. About 90% of this waste was found to be potentially recyclable and only 10% requiring landfilling. The compostable organic matter, in the form of food and garden waste, both with high moisture content (51 and 41%, respectively), represents 54% in mass and 21% in volume. The most common type of plastic in this waste is high density polyethylene, whose estimated disposal is about 5000kgday(-1). A socio-economic analysis of the waste generation indicates that low-income neighbourhoods discard relatively less packaging and more food waste, shoes and construction debris than middle and high income ones, which may be due to low purchasing power and schooling. Our findings indicate that more aluminium and uncoloured polyethylene terephthalate is discarded in the warmest months of the year, probably due to a greater consumption of canned and bottled drinks.  相似文献   
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The link between individual habitat selection decisions (i.e., mechanism) and the resulting population distributions of dispersing organisms (i.e., outcome) has been little-studied in behavioural ecology. Here we consider density-dependent habitat (i.e., host) selection for an energy- and time-limited forager: the mountain pine beetle (Dendroctonus ponderosae Hopkins). We present a dynamic state variable model of individual beetle host selection behaviour, based on an individual’s energy state. Field data are incorporated into model parameterization which allows us to determine the effects of host availability (with respect to host size, quality, and vigour) on individuals’ decisions. Beetles choose larger trees with thicker phloem across a larger proportion of the state-space than smaller trees with thinner phloem, but accept lower quality trees more readily at low energy- and time-states. In addition, beetles make habitat selection decisions based on host availability, conspecific attack densities, and beetle distributions within a forest stand. This model provides a framework for the development of a spatial game model to examine the implications of these results for attack dynamics of beetle populations.  相似文献   
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Previous studies of loggerhead sea turtles have concluded that drifting longlines were the main threat for immature specimens in the western Mediterranean, because immature loggerhead sea turtles mainly inhabit oceanic waters. However, recent aerial surveys have revealed large numbers of immature loggerhead sea turtles over the continental shelf of eastern mainland Spain, where turtles are exposed to neritic fishing gears but not to drifting longlines. We satellite-tracked seven loggerhead sea turtles (minimum straight carapace length (SCLmin) range: 36.5–55.0 cm) to assess whether the turtles in this region are vagrants from the adjoining oceanic regions or whether these loggerheads mostly inhabit the continental shelf. Satellite-tracking revealed that six of the tagged turtles avoided the oceanic realm and made extended use of the continental shelf, whereas only one individual could be considered a true vagrant as it avoided the continental shelf and primarily used the oceanic habitat. These results are in sharp contrast with those previously reported for immature loggerhead sea turtles of similar size from the south-western Mediterranean and fit well a relaxed ontogenic model that was recently proposed for loggerhead sea turtles in the central Mediterranean. Furthermore, these results demonstrate the vulnerability of loggerhead sea turtles of eastern mainland Spain to neritic fishing gears, as three of the seven turtles died and one was bycaught incidentally while being tracked over the continental shelf.  相似文献   
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As federal agencies and businesses rely more on cyber infrastructure, they are increasingly vulnerable to cyber attacks that can cause damages disproportionate to the sophistication and cost to launch the attack. In response, regulatory authorities call for focusing attention on enhancing infrastructure resilience. For example, in the USA, President Obama issued an Executive Order and policy directives focusing on improving the resilience and security of cyber infrastructure to a wide range of cyber threats. Despite the national and international importance, resilience metrics to inform management decisions are still in the early stages of development. We apply the resilience matrix framework developed by Linkov et al. (Environ Sci Technol 47:10108–10110, 2013) to develop and organize effective resilience metrics for cyber systems. These metrics link national policy goals to specific system measures, such that resource allocation decisions can be translated into actionable interventions and investments. In this paper, a number of metrics have been identified and assessed using quantitative and qualitative measures found in the literature. We have proposed a generic approach and could integrate actual data, technical judgment, and literature-based measures to assess system resilience across physical, information, cognitive, and social domains.  相似文献   
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Endemic goitre was prevalent in the population of Derbyshire in the UK for many centuries until it declined from the 1930s. A contemporary medical survey showed that endemicity of goitre was particularly higher in the Carboniferous limestone areas of the Derbyshire-Peak District. Unlike classical goitrous areas of the world, where the distribution of goitre has been found to be related to the iodine content in the environment, there is no such relationship reported for the Derbyshire-Peak District area. The present study reviews the presence of endemic goitre in this area with reference to iodine in different environmental media using past and present data. In comparison with the world average values, the iodine contents in the soil and sediment in the Peak District are not deficient, but compared to England, Wales and Scotland averages, these levels are low. As no information on the mobility and bioavailability of iodine of this area is available, a cautious approach is necessary before any assumption is made on the aetiology of endemic goitre. The study also discusses some hypotheses relating to the possible cause of endemic goitre in the limestone areas. Further research needs are suggested depending on the land use and geochemistry of the Peak District to determine the underlying causes of the former endemic goitre in this area.  相似文献   
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