929 resultados para situated
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We investigate the dynamic nature of metal speciation in colloidal dispersions using a recently proposed theory [J.P. Pinheiro, M. Minor, H.P. Van Leeuwen, Langmuir, 21 (2005) 8635] for complexing ligands that are situated on the surface of the particles. The new approach effectively modifies the finite rates of association/dissociation of the colloidal metal complexes, thus invoking consideration of the two basic dynamic criteria: the association/dissociation kinetics of the volume complexation reaction (the ‘‘dynamic’’ criterion), and the interfacial flux of free metal to a macroscopic surface due to dissociation of complex species (the ‘‘lability’’ criterion). We demonstrate that the conventional approach for homogeneous systems that assume a smeared-out ligand distribution, overestimates both the dynamics and the lability of metal complexes when applied to colloidal ligands. It is also shown that the increase of lability with increasing particle radius, as expected for a homogeneous solution, is moderated for spherical microelectrodes and practically eliminated for planar electrodes.
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Since 2004 several studies have been carried out in order to identify the main insect species that usually inhabiting the olive ecosystem. The field trials have taken place in two olive groves, one situated in Olhão and the other one in Loulé, both in Algarve and also under Integrated Pest Management (IPM). The sampling techniques used differ according to their purpose (sticky traps, pheromone traps, pitfall traps and samples of aerial parts of the trees such as inflorescences, leaves, fruits and branches). Results showed that the main insect pests of olive tree in southern Portugal were the olive fruit fly Bactrocera oleae Gmelin (Diptera: Tephritidae) and the olive moth Prays oleae Bernard (Lepidoptera: Hyponeumetidae). Other insect pests were also found in our olive groves namely the olive psyllid Euphyllura olivina Costa (Homoptera: Psyllidae), the olive dark beetle Phloeotribus scarabaeoides Bernard (Coleoptera: Curculionidae), the mediterranean black scale Saissetia oleae (Olivier) (Homoptera: Coccidae) and the olive thrip Liothripes oleae Costa (Thysanoptera: Phlaeothripidae). Concerning the auxiliary insects that were found in our olives groves they belong to the following orders and families: Diptera (Syrphidae), Coleoptera (Carabidae, Coccinelidae and Staphylinidae), Hemiptera (Anthocoridae and Miridae), Neuroptera (Chrysopidae) and Hymenoptera (Braconidae, Encyrtidae, Eulophidae, Formicidae and Trichogrammatidae).
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Every can of tuna purchased by the consumer has taken a long journey before reaching the supermarket shelves. For each can bought there is a lengthy process from sea to shelf. A large proportion of the tuna cans purchased in the European Union come all the way from West Africa; a developing region with a high dependency on fisheries. Amidst an ever-increasing demand for tuna products the global tuna fisheries are set to continue expanding, apparently one of the last natural resource based industries fit to do so in West Africa. Tuna is the biggest fisheries export and dominates the fisheries sector in Ghana, a country situated in West Africa. This thesis aims to understand how this globally important industrial fisheries functions in terms of procedures, practices, Governance and finance. Socioeconomic influences, in the setting of a developing country, were also examined. For these purposes a Value Chain Analysis was employed. A Value Chain Analysis is a tool commonly used to understand how different companies and organizations participate in a domestic policy environment, which directs conclusion in the global economy. This analysis has the potential to allow researchers to fully understand a commodity chain and hence identify realistic opportunities for consequential improvements. Interviews and questionnaires were employed in-field Ghana along with secondary data collection techniques. It was found that the fisheries functions at the production level under influences from large multinational companies and tends to operate with a certain degree of lawlessness. Governance over the value chain is well defined, however implementation is poor or non-existent. The processors, whom are also dominated by multinationals, exert some control over the producers and their sales, however the high value links which are highlighted occur at the retail stage. Socioeconomic dynamics acting in the chain included the lack of communication between the public and private sector, power imbalances amongst players at production, the role of local businesswomen as actors in the chain and the general characteristics of the workers in the industry. Value addition and upgrading are needed the most in Governance over the chain, especially within Monitoring, Control and Surveillance. The results of the study provide a wealth of material about the components of a cost-heavy fishing industry in a developing country; an industry on which many eyes have recently turned due to illegal fishing activities. It highlights clearly where funding and future focus are needed. This value chain can be used as a guide for those that need to comprehend the financial complexities and real life dynamics of the Ghanaian tuna fishing industry today.
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Relatório de estágio de mestrado, Estudos Regionais e Autárquicos, Universidade de Lisboa, Faculdade de Letras, 2012
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This paper draws on findings from a four‐year longitudinal research project, commissioned by the Department for Education and Skills (DfES), which investigated Variations in Teachers’ Work, Lives and Effectiveness (VITAE). Drawing on data gathered from 300 teachers working in 100 primary and secondary schools in England, the research identified associations between commitment and effectiveness (perceived and in terms of pupil attainment) and found that there were more, and less, effective teachers in each of six professional life phases. It found that teachers in each of these phases experienced a number of different scenarios that challenged their abilities to sustain their commitment (i.e. remain resilient). This paper discusses how these impact, positively and negatively, on teachers’ capacities for sustaining their initial commitment and associations between identity, well‐being and effectiveness. It finds that teacher identities are neither intrinsically stable nor intrinsically fragmented, but that they can be more, or less, stable and more or less fragmented at different times and in different ways according to the influence of the interaction of a number of personal, professional and situated factors. The extent to which teachers are able to and are supported in managing the scenarios they experience will determine their sense of effectiveness.
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This study aims to determine the potential origin of Olea pollen recorded in Badajoz in the Southwest of the Iberian Peninsula during 2009–2011. This was achieved using a combination of daily average and diurnal (hourly) airborne Olea pollen counts recorded at Badajoz (south-western Spain) and Évora (south-eastern Portugal), an inventory of olive groves in the studied area and air mass trajectory calculations computed using the HYSPLIT model. Examining olive pollen episodes at Badajoz that had distinctly different diurnal cycles in olive pollen in relation to the mean, allowed us to identify three different scenarios where olive pollen can be transported to the city from either distant or nearby sources during conditions with slow air mass movements. Back trajectory analysis showed that olive pollen can be transported to Badajoz from the West on prevailing winds, either directly or on slow moving air masses, and from high densities of olive groves situated to the Southeast (e.g. Andalucía). Regional scale transport of olive pollen can result in increased nighttime concentrations of this important aeroallergen. This could be particularly important in Mediterranean countries where people can be outdoors during this time due to climate and lifestyle. Such studies that examine sources and the atmospheric transport of pollen are valuable for allergy sufferers and health care professionals because the information can be incorporated into forecasts, the outputs of which are used for avoiding exposure to aeroallergens and planning medication. The results of studies of this nature can also be used for examining gene flow in this important agricultural crop.
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This paper aims to reflect upon the potential analytical utility of the political discourse analysis framework proposed by Isabela Fairclough and Norman Fairclough (2012). This framework represents the most recent substantive development upon Norman Fairclough's past work situated within the wider school of Critical Discourse Analysis, building upon his influential position this methodological tradition. Central to this development is the additional emphasis placed upon the necessity to conceptualise all political discourse as 'argumentative' in nature, given that political actors are ultimately proposing or refuting particular courses of concrete future action. This paper will therefore apply Fairclough and Fairclough's model to provisional data derived from an ongoing doctoral thesis which considers the nature of political discourse relating to sport, the Glasgow 2014 Commonwealth Games and Scottish independence, with an ultimate aim of critically considering the benefits and limitations of applying this analytical framework as a methodological tool within this ongoing study.
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This study improves the spatial coverage of top-down Ambrosia pollen source inventories for Europe by expanding the methodology to Austria, a country that is challenging in terms of topography and the distribution of ragweed plants. The inventory combines annual ragweed pollen counts from 19 pollen-monitoring stations in Austria (2004–2013), 657 geographical observations of Ambrosia plants, a Digital Elevation Model (DEM), local knowledge of ragweed ecology and CORINE land cover information from the source area. The highest mean annual ragweed pollen concentrations were generally recorded in the East of Austria where the highest densities of possible growth habitats for Ambrosia were situated. Approximately 99% of all observations of Ambrosia populations were below 745 m. The European infection level varies from 0.1% at Freistadt in Northern Austria to 12.8% at Rosalia in Eastern Austria. More top-down Ambrosia pollen source inventories are required for other parts of Europe.
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Fungi belonging to the genus of Alternaria are recognised as being significant plant pathogens, and Alternaria allergens are one of themost important causes of respiratory allergic diseases in Europe. This study aims to provide a detailed and original analysis of Alternaria transport dynamics in Badajoz, SW Spain. This was achieved by examining daily mean and hourly observations of airborne Alternaria spores recorded during days with high airborne concentrations of Alternaria spores (N100 s m−3) from 2009 to 2011, as well as four inventory maps of major Alternaria habitats, the overall synoptic weather situation and analysis of air mass transport using Hybrid Single Particle Lagrangian Integrated Trajectory model and geographic information systems. Land use calculated within a radius of 100 km from Badajoz shows that crops and grasslands are potentially the most important local sources of airborne Alternaria spores recorded at the site. The results of back trajectory analysis showthat, during the examined four episodes, the two main directions where Alternaria source areas were located were: (1) SW–W; and (2) NW–NE. Regional scale and long distance transport could therefore supplement the airborne catch recorded at Badajoz with Alternaria conidia originating from sources such as crops and orchards situated in other parts of the Iberian Peninsula.
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Air quality is an increasing concern of the European Union, local authorities, scientists and most of all inhabitants that become more aware of the quality of the surrounding environment. Bioaerosols may be consisted of various elements, and the most important are pollen grains, fungal spores, bacteria, viruses. More than 100 genera of fungal spores have been identified as potential allergens that cause immunological response in susceptible individuals. Alternaria and Cladosporium have been recognised as the most important fungal species responsible for respiratory tract diseases, such as asthma, eczema, rhinitis and chronic sinusitis. While a lot of attention has been given to these fungal species, a limited number of studies can be found on Didymella and Ganoderma, although their allergenic properties were proved clinically. Monitoring of allergenic fungal spore concentration in the air is therefore very important, and in particular at densely populated areas like Worcester, UK. In this thesis a five year spore data set was presented, which was collected using a 7-day volumetric spore trap, analysed with the aid of light microscopy, statistical tests and geographic information system techniques. Although Kruskal-Wallis test detected statistically significant differences between annual concentrations of all examined fungal spore types, specific patterns in their distribution were also found. Alternaria spores were present in the air between mid-May/mid-June until September-October with peak occurring in August. Cladosporium sporulated between mid-May and October, with maximum concentration recorded in July. Didymella spores were seen from June/July up to September, while peaks were found in August. Ganoderma produced spores for 6 months (May-October), and maximum concentration could be found in September. With respect to diurnal fluctuations, Alternaria peaked between 22:00h and 23:00h, Cladosporium 13:00-15:00h, Didymella 04:00-05:00h and 22:00h-23:00h and Ganoderma from 03:00h to 06:00h. Spatial analysis showed that sources of all fungal species were located in England, and there was no evidence for a long distance transport from the continent. The maximum concentration of spores was found several hours delayed in comparison to the approximate time of the spore release from the crops. This was in agreement with diurnal profiles of the spore concentration recorded in Worcester, UK. Spores of Alternaria, Didymella and Ganoderma revealed a regional origin, in contrast to Cladosporium, which sources were situated locally. Hence, the weather conditions registered locally did not exhibit strong statistically significant correlations with fungal spore concentrations. This has had also an impact on the performance of the forecasting models. The best model was obtained for Cladosporium with 66% of the accuracy.
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Thesis (Ph.D.)--University of Washington, 2014
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Tese (doutorado)—Universidade de Brasília, Faculdade de Educação, Programa de Pós-Graduação em Educação, 2016.
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Senior thesis written for Oceanography 445
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The chapter considers the role that urban consolidation centres (UCCs) can play in helping to reduce goods vehicle traffic and its environmental impacts in urban areas. A UCC is a logistics facility that is situated in relatively close proximity to the area that it serves. Goods destined for this area are dropped off at the UCC, and are sorted and consolidated onto goods vehicles for delivery to their final destinations, often using environmentally friendly vehicles such as electric and gas-powered goods vehicles, and electrically-assisted cycles. The development of UCCs since their first appearance in the 1970s is reviewed and the various types of UCC categorised. The freight transport and logistics advantages offered by UCCs are discussed. Case studies of four recent UCC trials are included. The objectives, operational and financial aspects and impacts of these UCCs are compared and their critical success factors identified.
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In this paper I outline possibilities for, and issues arising from, opposition towards the dominant ideologies and practices of marketing knowledge (Hirschman 1993) through an engagement with feminist epistemology (Longino 1991, Harding 1987). Feminist epistemology is a political branch of naturalised epistemology (Quine 1969) primarily concerned with critique of constructions of gender, gender norms and gendered interests within the production of knowledge (Anderson 1995) and with theorising, grounding and legitimating feminist knowledge making practices (Harding 1987). It is most often associated with the feminist critique of science, and with feminist science and technology studies (Haraway 1987, Wajman 1997). Feminist epistemology asks the question, ‘what is the nature of the feminist critical project as a way of knowing?’ (McLennan 1995:392). This paper outlines the basis of the feminist critique of knowledge generally, and as applied to marketing knowledge, offers description of the three main epistemological approaches to this question and suggestions for their application in practice. The paper progresses important work by consumer behaviour theorists (Bristor and Fischer 1993, Hirschman 1993) on the potentials of feminist ways of knowing for marketing and consumer behaviour by moving beyond the tripartite of feminist approaches outlined, and extending the discussion to take into account the development of situated knowledges theory (Haraway 1989, 1997), which has become so important in the decade since these papers were written. It joins ongoing conversations in consumer behaviour and marketing that share similar feminist concerns (Catterall et al 1997, 2000, 2005, Bettany and Woodruffe Burton 1999, 2005, and Hogg et al 1999, 2000) but in this contribution it takes a slightly tangential approach, seeing marketing knowledge in terms of its epistemic culture by using a model of masculinity in academic cultures from feminist theory (Wagner 1994) to help conceptualise it as such. The dominant masculine ideology of marketing knowledge both in execution (Penaloza 1994, Bristor and Fischer 1994, Fischer and Bristor 1993, Woodruffe 1996), and values (Hirschman 1993, Brown 2000, Desmond 1997) has been well documented over the past fifteen years. However, although the basis of this, how is it manifested and how a feminist informed marketing knowledge could be achieved, have been addressed somewhat in the literature (Bristor and Fischer 1993, Hogg, Bettany and Long 2000) an updated rendering is necessary which focuses specifically on epistemology and situates this discussion within a cultural framework. To do this I use the notions of cultural masculinity in academic disciplines developed by Wagner (1994) of ‘organisational egocentrism’, ‘fake collectivity’ and ‘de realisation’. With these, I raise important and specific issues around the notion of the masculinity of marketing knowledge, and then present an outline of feminist epistemologies to illustrate how different feminist approaches to knowledge would address these concerns.