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Life cycle thinking is a good approach to be used for environmental decision-support, although the complexity of the Life Cycle Assessment (LCA) studies sometimes prevents their wide use. The purpose of this paper is to show how LCA methodology can be simplified to be more useful for certain applications.In order to improve waste management in Catalonia (Spain), a Cumulative Energy Demand indicator (LCA-based) has been used to obtain four mathematical models to help the government in the decision of preventing or allowing a specific waste from going out of the borders. The conceptual equations and all the subsequent developments and assumptions made to obtain the simplified models are presented.One of the four models is discussed in detail, presenting the final simplified equation to be subsequently used by the government in decision making.The resulting model has been found to be scientifically robust, simple to implement and, above all, fulfilling its purpose: the limitation of waste transport out of Catalonia unless the waste recovery operations are significantly better and justify this transport.  相似文献   
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In October 2008, the 5th Environmental Management for Sustainable Universities (EMSU) international conference was held in Barcelona, Spain. It dealt with the need to rethink how our higher educational institutions are facing sustainability. This special issue has been primarily derived from contributions to that conference. This issue builds upon related academic international publications, which have analysed how to use the critical position of universities to accelerate their pace of working to help to make the transition to truly SUSTAINABLE SOCIETIES!This issue focus is on the ‘softer’ issues, such as changes in values, attitudes, motivations, as well as in curricula, societal interactions and assessments of the impacts of research. Insights derived from the interplay of the ‘softer’ issues with the ‘harder’ issues are empowering academic leaders to effectively use leverage points to make changes in operations, courses, curricula, and research. Those changes are being designed to help their students and faculty build resilient and sustainable societies within the context of climate change, the Decade of Education for Sustainable Development (DESD), and the UN Millennium Development Goals (MDGs).The overall systems approach presented by Stephens and Graham provides a structured framework to systematize change for sustainability in higher education, by stressing on the one hand the need for “learning to learn” and on the other hand by integrating leadership and cultural aspects. The “niche” level they propose for innovative interactions between practitioners such as EMSU is exemplary developed by all of the other documents in this special issue. To highlight some of the key elements of the articles in this issue, there are proposals for new educational methods based in sustainability science, a set of inspirational criteria for SD research activities, new course ranking and assessment methods and results of psychological studies that provide evidence that participatory approaches are the most effective way to change values within university members in order to facilitate the development and sharing of new sustainability norms.  相似文献   
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Electrochemical advanced oxidation processes (EAOPs) are environmentally friendly methods based on the destruction of organic pollutants in wastewaters with in situ electrogenerated hydroxyl radical. This species is formed in anodic oxidation (AO) from water oxidation at the anode and in indirect electro-oxidation methods like electro-Fenton (EF) and photoelectro-Fenton (PEF) also from reaction between catalytic Fe2+ and H2O2 continuously produced at the O2-diffusion cathode. The PEF method involves the irradiation of the treated solution with UVA light to enhance the photolysis of organics including Fe(III) complexes. In this work, the oxidation power of such EAOPs to decontaminate synthetic wastewaters of the biocide chloroxylenol (4-chloro-3,5-dimethylphenol) at pH 3.0 is comparatively examined with an undivided electrolytic cell containing a Pt or boron-doped diamond (BDD) anode and a stainless steel or O2-diffusion cathode. The initial chlorine is released as Cl(-) ion, which remains stable in the medium using Pt or is oxidized to Cl2 on BDD. The biocide solutions can be completely decontaminated using AO with a BDD anode, as well as PEF with a Pt or BDD anode. The PEF procedure with a BDD anode is the most powerful method leading to total mineralization in about 300 min, practically independent of current density. When current density rises, the degradation rate of processes increases, but they become less efficient due to the larger enhancement of waste reactions of oxidants. Chloroxylenol is much more rapidly removed in EF and PEF than in AO. 2,6-dimethylhydroquinone, 2,6-dimethyl-p-benzoquinone and 3,5-dimethyl-2-hydroxy-p-benzoquinone are identified as aromatic by-products, and maleic, malonic, pyruvic, acetic and oxalic acids are found as generated carboxylic acids. A general pathway for chloroxylenol mineralization by all EAOPs including the above by-products is proposed.  相似文献   
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The study of successional gradients may help to understand the relative influence of habitat structure and competition on territory characteristics. Here, we evaluate the effects of vegetation cover, conspecific and heterospecific densities, and distance to the nearest neighbor on territory size, shape, and overlap in insectivorous birds. We studied these effects along a gradient of postfire habitat regeneration in which foliage cover and densities of focal species varied several-fold. We delineate 197 territories (minimum convex polygons) of the shrub-dwelling Dartford warbler (Sylvia undata) and 255 of the syntopic Sardinian (Sylvia melanocephala), subalpine (Sylvia cantillans) and melodious (Hippolais polyglotta) warblers at three plots in NE Catalonia (Spain and France) in 1987–2005. After accounting for the effect of the number of locations used to delineate polygons, generalized linear mixed models (GLMM) showed a reduction in territory area of the Dartford warbler as conspecific density increased and distance to nearest neighbor decreased, in accordance with the contender pressure hypothesis for territory size regulation. Heterospecific density was not included in the final model of territory size and the effect of habitat structure was marginal. Territory roundness was positively correlated with its size and with conspecific density, probably in relation to energetic constraints, and negatively with heterospecific density. Territorial exclusion was almost complete among Dartford warblers, whereas interspecific territory overlap was extensive and tended to increase with heterospecific density and with structural diversity along the gradient. Our results support the hypothesis that Mediterranean warbler coexistence derives from ecological segregation and not from interspecific territoriality.  相似文献   
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This paper explains the strategy and procedures followed by the Universitat Autònoma de Barcelona (UAB) to spread green purchasing practices throughout its administration and supply chain, highlighting the identified barriers against their implementation and monitoring, and showing the actions carried out to overcome them. The university's green supply chain management has been analysed in five selected case studies: office material, recycled toner cartridges, fair trade coffee, reusable glass bottles and catering services. These cover the wide range of purchasing patterns currently taking place at UAB taking into account both the acquisition model (directly or indirectly through contracted firms) and the supply chain management perspective (linear or loop). A comparison of the different cases is carried out and some general rules are created that should be investigated further.  相似文献   
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Forest fires represent a major driver of change at the ecosystem and landscape levels in the Mediterranean region. Environmental features and vegetation are key factors to estimate the ecological vulnerability to fire; defined as the degree to which an ecosystem is susceptible to, and unable to cope with, adverse effects of fire (provided a fire occurs). Given the predicted climatic changes for the region, it is urgent to validate spatially explicit tools for assessing this vulnerability in order to support the design of new fire prevention and restoration strategies. This work presents an innovative GIS-based modelling approach to evaluate the ecological vulnerability to fire of an ecosystem, considering its main components (soil and vegetation) and different time scales. The evaluation was structured in three stages: short-term (focussed on soil degradation risk), medium-term (focussed on changes in vegetation), and coupling of the short- and medium-term vulnerabilities. The model was implemented in two regions: Aragón (inland North-eastern Spain) and Valencia (eastern Spain). Maps of the ecological vulnerability to fire were produced at a regional scale. We partially validated the model in a study site combining two complementary approaches that focused on testing the adequacy of model’s predictions in three ecosystems, all very common in fire-prone landscapes of eastern Spain: two shrublands and a pine forest. Both approaches were based on the comparison of model’s predictions with values of NDVI (Normalized Difference Vegetation Index), which is considered a good proxy for green biomass. Both methods showed that the model’s performance is satisfactory when applied to the three selected vegetation types.  相似文献   
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Two cases of twin reversed arterial perfusion (TRAP) sequence with relevant ultrasound features that would help an accurate diagnosis are described. Available management options are proposed and discussed.  相似文献   
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The degradation of 100ml of solutions with paracetamol (N-(4-hydroxyphenyl)acetamide) up to 1 g l(-1) in the pH range 2.0-12.0 has been studied by anodic oxidation in a cell with a boron-doped diamond (BDD) anode and a graphite cathode, both of 3-cm2 area, by applying a current of 100, 300 and 450 mA between 25 and 45 degrees C. Complete mineralization is always achieved due to the great concentration of hydroxyl radical (*OH) generated at the BDD surface, with release of NH4+ and NO3- ions. The mineralization rate is pH-independent, increases with increasing applied current and temperature, but decreases when drug concentration raises from 315 mg l(-1). Reversed-phase chromatography revealed a similar complex paracetamol decay in acid and alkaline media. Ion-exclusion chromatography allowed the detection of oxalic and oxamic acids as ultimate carboxylic acids. When the same solutions have been comparatively treated with a Pt anode, a quite poor mineralization is found because of the production of much lower *OH concentration. Under these conditions, the degradation rate is enhanced in alkaline medium and polymerization of intermediates is favored in concentrated solutions. Paracetamol can be completely destroyed with Pt and its kinetics follows a pseudo-first-order reaction with a constant rate independent of pH.  相似文献   
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