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231.
This research has been motivated by a real-life problem of a waste cooking oil collection system characterized by the existence of multiple depots with an outsourced vehicle fleet, where the collection routes have to be plan. The routing problem addressed allows open routes between depots, i.e., all routes start at one depot but can end at the same or at a different one, depending on what minimizes the objective function considered. Such problem is referred as a Multi-Depot Vehicle Routing Problem with Mixed Closed and Open Inter-Depot Routes and is, in this paper, modeled through a mixed integer linear programming (MILP) formulation where capacity and duration constraints are taken into account. The model developed is applied to the real case study providing, as final results, the vehicle routes planning where a decrease of 13% on mileage and 11% on fleet hiring cost are achieved, when comparing with the current company solution.  相似文献   
232.
Geodiversity is considered as the natural range of geological, geomorphological, and soil features, including their assemblages, relationships, properties, interpretations, and systems. A method developed for the quantitative assessment of geodiversity was applied to Paraná, a Brazilian state with an area of about 200,000 km2. The method is based on the overlay of a grid over different maps at scales ranging from 1/500,000 to 1/650,000, with the final Geodiversity Index the sum of five partial indexes calculated on a 25 × 25 km grid. The partial indexes represent the main components of geodiversity, including geology (stratigraphy and lithology), geomorphology, paleontology, and soils. The fifth partial index covers mineral occurrences of geodiversity, such precious stones and metals, energy and industrial minerals, mineral waters, and springs. The Geodiversity Index takes the form of an isoline map that can be used as a tool in land-use planning, particularly in identifying priority areas for conservation, management, and use of natural resources at the state level.  相似文献   
233.
Tony Matthews 《Local Environment》2013,18(10):1089-1103
This paper characterises climate change as a “transformative stressor”. It argues that institutional change will become increasingly necessary as institutions seek to reorientate governance frameworks to better manage the transformative stresses created by climate change in urban environments. Urban and metropolitan planning regimes are identified as central institutions in addressing this challenge. The operationalisation of climate adaptation is identified as a central tenet of a comprehensive urban response to the transformative stresses that climate change is predicted to create. Operationalisation refers to climate adaptation becoming incorporated, codified and implemented as a central tenet of urban planning governance. This paper has three purposes. First, it examines conceptual perspectives on the role of transformative stressors in compelling institutional change. Second, it establishes a conceptual approach that characterises climate change as a transformative stressor requiring institutional change within planning frameworks. Third, it reports emergent results and analysis from an empirical inquiry which examines how the metro-regional planning regime of Southeast Queensland has responded to climate change as a transformative stressor via institutional change and the operationalisation of climate adaptation.  相似文献   
234.
Environmental Science and Pollution Research - Free-living birds play an important role as bioindicators in natural environments. In this study, we used the micronucleus test and nuclear...  相似文献   
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Claims of employment and productivity gains from environmental taxation are examined in the context of recent policy developments which have extended the traditional role of economic instruments in environmental regulation. Although the general existence of such spin-offs cannot be established, the debate has clarified guidelines for designing and implementing specific environmentally based taxes to help deliver sustainable development. Recent UK tax proposals have started to draw on the flexibility of fiscal instruments to tackle environmental problems. Innovations include earmarking taxes to fund allied spatial and sectoral programmes, recycling revenues to provide fiscally neutral improvements in tax efficiency and using taxation to help promote eco-efficiency.  相似文献   
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Fetal sacrococcygeal teratoma can lead to a high output cardiac failure resulting in hydrops fetalis. One of the prenatal therapeutic options is to occlude the feeding vessels by radiofrequency ablation. We present a case of fetal sacrococcygeal teratoma diagnosed at 13 weeks of gestation. The tumour increased in size more than 100-fold over 5 weeks causing polyhydramnios and cardiac and placental enlargement. Thermocoagulation was performed at 18 weeks' gestation by passing an insulated electric wire through an 18-gauge needle placed close to the feeding vessels of the tumour at its neck. Blood supply to the tumour was successfully reduced. However, fetal death was diagnosed 2 days after the procedure. We speculate that it may be safer to limit the extent of coagulation in one attempt but to repeat the procedure at a later stage when necessary. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
239.
Laurencia dendroidea shows high inter- and intrapopulation variability in the amount of the sesquiterpene elatol, caused by genetic variation as well as environmental factors. To test the independent effect of physical and nutritional conditions, the growth and the levels of elatol in L. dendroidea clones were evaluated under different conditions of temperature, salinity, irradiance, and culture medium in the laboratory. Growth of L. dendroidea was clearly affected by all these factors, but elatol levels were influenced only by temperature and salinity. Better conditions for growth did not produce a similar effect on elatol production in L. dendroidea, contradicting the carbon/nutrient balance and growth/differentiation balance models. On the contrary, severe conditions of temperature and salinity promoted a decrease in elatol levels, as predicted by the environmental stress model. Our results using clones indicated that abiotic factors clearly take part in fostering chemical variations observed in natural populations, in addition to genetic factors, and can promote differential susceptibility of plant specimens to natural enemies.  相似文献   
240.
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