34 resultados para Legal Environment of Distribution,
em CentAUR: Central Archive University of Reading - UK
Resumo:
The extent to which airborne particles penetrate into the human respiratory system is determined mainly by their size, with possible health effects. The research over the scientific evidence of the role of airborne particles in adverse health effects has been intensified in recent years. In the present study, seasonal variations of PM10 and its relation with anthropogenic activities have been studied by using the data from UK National Air Quality Archive over Reading, UK. The diurnal variation of PM10 shows a morning peak during 7:00-10:00 LT and an evening peak during 19:00-22:00 LT. 3 The variation between 12:00 and 17:00 LT remains more or less steady for PM10 with the minimum value of similar to 16 mu g m(-3). PM10 and black smoke (BS) concentrations during weekdays were found to be high compared to weekends. A reduction in the concentration of PM10 has been found during the Christmas holidays compared to normal days during December. Seasonal variations of PM10 showed high values during spring compared to other seasons. A linear relationship has been found between PM10 and NO, during March, July, November and December suggesting that most of the PM10 is due to local traffic exhaust emissions. PM10 and SO2 concentrations showed positive correlation with the correlation coefficient of R-2 = 0.65 over the study area. Seasonal variations of SO2 and NOx showed high concentrations during winter and low concentrations during spring. Fraction of BS in PM10 has been found to be 50% during 2004 over the study area. (C) 2005 Elsevier Ltd. All rights reserved.
Resumo:
Habitat-based statistical models relating patterns of presence and absence of species to habitat variables could be useful to resolve conservation-related problems and highlight the causes of population declines. In this paper, we apply such a modelling approach to an endemic amphibian, the Sardinian mountain newt Euproctus platycephalus, considered by IUCN a critically endangered species. Sardinian newts inhabit freshwater habitat in streams, small lakes and pools on the island of Sardinia (Italy). Reported declines of newt populations are not yet supported by quantitative data, however, they are perceived or suspected across the species' historical range. This study represents a first attempt trying to statistically relate habitat characteristics to Sardinian newt occurrence and persistence. Linear regression analysis revealed that newts are more likely to be found in sites with colder water temperature, less riparian vegetation and, marginally, absence of fish. The implications of the results for the conservation of the species are discussed, and suggestions for the short-term management of newt inhabited sites suggested. (C) 2003 Elsevier Ltd. All rights reserved.
Resumo:
The following paper builds on ongoing discussions over the spatial and territorial turns in planning, as it relates to the dynamics of evidence-based planning and knowledge production in the policy process. It brings this knowledge perspective to the organizational and institutional dynamics of transformational challenges implicit in the recent enlargement of the EU. Thus it explores the development of new spatial ideas and planning approaches, and their potential to shape or ‘frame’ spatial policy through the formulation of new institutional arrangements and the de-institutionalization of others. That is, how knowledge is created, contested, mobilized and controlled across governance architectures or territorial knowledge channels. In so doing, the paper elaborates and discusses a theoretical framework through which the interplay of knowledge and policymaking can be conceptualized and analyzed.
Resumo:
The majority of the world’s population now live in cities. This poses great challenges, but also great opportunities in terms of tackling climate change, resource depletion and environmental degradation. Policy agendas have increasingly focused on how to develop and maintain ‘integrated sustainable urban development’, and a number of theoretical conceptualisations of urban transition have been formulated to help our thinking and understanding in both developed and developing countries. Drawing on examples around the world the paper aims to examine the key ‘critical success factors’ that need to be in place for cities to traverse a pathway to a more sustainable future in urban development terms by 2050. The paper explores how important the issues of ‘scale’ is in the context of complexity and fragmentation in the city’s built environment, identifies the lessons that can be learned for future sustainable urban development, and the further research which is needed to address future urban transitions to 2050.
Resumo:
Let 0 denote the level of quality inherent in a food product that is delivered to some terminal market. In this paper, I characterize allocations over 0 and provide an economic rationale for regulating safety and quality standards in the food system. Zusman and Bockstael investigate the theoretical foundations for imposing standards and stress the importance of providing a tractable conceptual foundation. Despite a wealth of contributions that are mainly empirical (for reviews of these works see, respectively, Caswell and Antle), there have been relatively few attempts to model formally the linkages between farm and food markets when food quality and consumer safety are at issue. Here, I attempt to provide such a framework, building on key contributions in the theoretical literature and linking them in a simple model of quality determination in a vertically related marketing channel. The food-marketing model is due to Gardner. Spence provides a foundation for Pareto-improving intervention in a deterministic model of quality provision, and Leland, building on the classic paper by Akerlof, investigates licensing and minimum standards when the information structure is incomplete. Linking these ideas in a satisfactory model of the food markets is the main objective of the paper.