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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Public access and recreation in the countryside and their impacts on biodiversity : an interdisciplinary analysis

Barlow, Catherine January 2010 (has links)
Despite its relatively small land mass (approximately 245 000 sq km), the UK is now home to close to 61 million people (Office of National Statistics, 2009). This high population density (243 per km2), aggregated in major cities, leaves the remaining land area, under great stress to produce food and housing and recreation opportunities for the country’s ever increasing population. The principle of ‘right of way’, allowing walkers to cross privately owned land on paths or tracks, totalling about 140,000 miles (225,000km) makes recreation in Britain unique. In the mosaic of the English countryside, linear features (such as field boundaries, woodland edges and streams) are often the natural route of public rights of way. The importance of field boundaries to wildlife within the agricultural landscape, has been recognised for several years. Disturbance by public access and recreation is another potential source of detriment to farmland wildlife, and one that is noticeably absent from current research. As managers consider how to limit impacts, they are faced with difficult decisions that affect countryside users, landowners and biodiversity. A call by authors for better integrated social and ecological research regarding recreation impacts has been heard in recent years. This study takes a holistic approach to this challenge utilizing a questionnaire survey of farmers/landowners, recreational groups and members of the public in the Midland counties of England to identify areas of conflict between recreational users and identify areas current management that could be improved. Disturbance to wildlife and damage to tracks from ‘trampling’ were two topics commonly identified as areas of concern to landowners, recreational groups and the general public. Study two attempts to account for the differences in diversity, abundance and spatial distribution of farmland birds along a disturbance gradient (footpath). No significant difference between bird abundance or species richness on transects following public rights of way and control transects was found in this study, suggesting that presence of public rights of way with ‘low’ recreational disturbance does not impact on the abundance of farmland birds in lowland England. Study three investigates an important consideration in management of recreation and access - the durability or vulnerability of a vegetation type to activity. Low resistance to four studied activities (All Terrain Vehicles, horse & rider, walker and mountain bike), was exhibited by MG7 grassland in this study; all four activity types showing a 50% cover loss at 40 passes or less. The low resistance of grassland to trampling could have implications for management since areas of disturbance become obvious with just a few passes – these areas will tend to attract more use, and therefore lead to trail formation. In the case of Rights of Way that follow an obvious route such as a field boundary are less likely to have issues with be a problem. ROW without an obvious route to follow (through pasture or grassland) or physical boundary (hedge or crop edge) to guide the trail user wandering from the intended trail and possible formation of secondary trails could occur. This potential problem argues for the use good signage to avoid trail users losing their way from the intended route. The results of the three studies were drawn together in the final chapter to formulate suggestions for management of public access and recreation in lowland farmland.
62

Social representations of nature : the case of the 'Braer' oil spill in Shetland

Gervais, Marie-Claude January 1997 (has links)
In this thesis, the work of Serge Moscovici on the human history of nature is made relevant to his theory of social representations. This theoretical synthesis breaks away both from the realist assumption of a given, immutable and non-socialised nature, and from the individualist conceptualisations of man-environment relations which still dominate environmental, ecological and social psychology. It is argued that social representations are not solely the concern of epistemology; they have ontological correlates and are involved in the social construction on nature. The empirical study investigates how social representations of nature functioned in Shetland - a society which combines traditional and late modern features - in the wake of the Braer oil spill in January 1993. The findings are based on the qualitative analysis of 17 individual interviews, five small group discussions, 375 articles from the newspaper The Shetland Times, the transcript of a public debate on the Cost of the Braer for Shetland and, more generally, participant observation. The analysis reveals the synchronic existence of three distinct, yet interrelated, social representations of nature: organic, mechanistic and cybernetic. Each of them is intrinsically related to a particular sense of identity, mode of knowledge, and mode of relations to nature. "Real Shetlanders" hold predominantly organic representations, whereby nature constitutes a repository of their history, a definer of their identity as a marginal but resilient community. It is known through direct engagement and participation in a life world. By contrast, "Sooth-Moothers" (outsiders) hold mechanistic and/or cybernetic representations which rest upon some universal, abstract knowledge of the systemic properties of "the environment". Their relations to nature oscillate between domination, mastery and protection. However, the imperatives facing the community, together with constant exchanges of information via the media, blur the boundaries between representations.
63

New urbanist housing in Toronto, Canada : a critical examination of the structures of provision and housing producer practices

Moore, Susan Margaret January 2005 (has links)
The empirical focus for this thesis research is Toronto, Canada where four case study sites are investigated and fifty-seven semi-structured interviews conducted with a range of actors both directly and indirectly involved in the creation of New Urbanist-inspired development projects. Two of the sample projects are situated in greenfield locations outside the administrative boundary of the City of Toronto, and two are situated in brownfield locations on formerly developed lands, both within the urban core of the City of Toronto. The contrasting contexts of the study units have been purposefully selected to explore the possibility of multi-factor causality involving contrasts of place, process, time, and social interaction. Underpinning this empirical research is the contention that the structures of provision model provides a useful approach for framing housing production research. However, it is argued that the evaluative power of this approach is limited by its inability to adequately account for how and why the New Urbanist form of provision has emerged, been legitimised, and normalised as 'best practice' within Toronto. In an unorthodox move, the final chapter of this thesis takes the level of theorisation enabled via the empirical framework of the structures of provision a step further to address this shortcoming. This is done by applying a 'rationalities' perspective to the investigation of how and why New Urbanism has become such a powerful force within Toronto's development cultures.
64

Negotiating youth work : moral geographies of the Boys' Brigade in Scotland

Kyle, Richard G. January 2006 (has links)
The sites and settings of structured youth work have been a neglected sphere of study in contemporary human geography. This thesis addresses this silence through an examination of The Boys’ Brigade – a voluntary Christian uniformed youth work movement. Limited in geographic scope to Scotland, the thesis draws upon a multiple-methods research strategy comprising: a mail-based questionnaire, semi-structured interviews, and a period of participant observation, incorporating participatory approaches with boys. Resting upon Foucouldian theoretical foundations, and written with audiences both within and without academia in mind, the thesis argues that a failure to appreciate the spatialities of structured youth work settings invariably results in partial accounts of both the motives underpinning their voluntary provision by adults’ and boys’ participation in them. More specifically, it suggests that the spaces of structured youth work are realised through small-scale processes of negotiation between boys and adults that stabilise a shared spatio-temporal regime – a structure – through which youth work is conducted by both adults and boys. It contends that it is space itself, and particularly its purposive ordering, that is both enlisted and resisted to achieve this fleeting stabilisation with its attendant disciplinary and developmental ends. In so doing the thesis delivers an analytical framework through which other spaces of structured youth work can be read that, by remaining alert to the interweaving of the geographies of voluntary provision and participation, neither overplays adults’ nor downplays young people’s agency in their creation.
65

Pigeon geographies : aesthetics, organisation, and athleticism in British pigeon fancying, c.1850-1939

Whiston, Kate January 2017 (has links)
This thesis provides new ways of thinking about human-bird encounters under domestication, providing the first substantive geographical study of ‘pigeon geographies’. It explores the spaces, practices, and human-pigeon relationships involved in pigeon showing and long-distance pigeon racing in Britain, from the mid-nineteenth century up until World War Two. The growth of fancy pigeon exhibitions was part of a wider Victorian passion for domesticating animals, at a time when human bodies were also subject to increasing aesthetic and moral scrutiny. Long-distance pigeon racing emerged at the end of this period, organised competitive sport more generally seen as an important means of moral improvement and identity expression. Like many other competitive pastimes in the second half of the nineteenth century, then, institutional bodies were formed to manage the expansion of showing and long-distance racing. The Pigeon Club and the Marking Conference were formed in 1885 to oversee British pigeon exhibitions, whilst the National Homing Union, formed in 1896, governed British long-distance pigeon racing. Both pastimes facilitated the formation of social worlds around varieties of domestic pigeon (Columba livia) and their respective practices. Whilst these pastimes historically had strong concentrations of male working-class followers – particularly in the north-west and north-east – they were both widespread throughout Britain and spanned all socio-economic classes, although accounts of female fanciers were rare. Through the exhibition of pigeons, fanciers debated and defined aesthetics, formulating breeding standards for each fancy breed, and questioning the ways in which pigeons were manipulated – sometimes contentiously – to produce the ‘ideal’. Long-distance pigeon racers, on the other hand, sought to understand and hone their birds’ athletic abilities, becoming entangled in scientific debate about homing, as well as geographical questions about the conduct and regulation of their sport. Racers were also drawn into aesthetic debates, exhibiting their racing birds during the off-season, the show pen becoming a fascinating frontier between showing and racing. Through the organisation of the spaces and practices that made up the fabric of these pastimes, pigeon showing and long-distance racing reconfigured both humans and their birds, the two becoming closely intertwined through collaborative encounters.
66

A matter of evolutionary life and death : an ecological model of growth and development in Homo erectus

Buckley, Carina A. January 2005 (has links)
This thesis investigates the evolutionary ecology of Homo erectus, focussing on the differential impact of the environment on the species' life history strategy. Departing from previous studies in taking an integrated approach, it examines the related factors of age-specific mortality, encephalisation, and the rate and energetic burden of growth, in order to identify the mechanism by which H. erectus adapted to a diverse range of climates and environments, and how thoroughly that adaptation was achieved. An exploration of the environmental tolerance of H erectus is framed within a model that shows regions that comprised the core of the species, where tolerance is highest and conditions are optimum for growth and reproduction, and periphery regions which fall towards the extremes of tolerance and have repercussive effects on encephalisation, juvenile mortality and growth. Life history traits should vary accordingly, allowing the development of a model for the relationship between environmental variation and the differential evolution of H. erectus. The work is organised thematically. Having provided an overview of evolutionary ecology and introduced the concept of paleo-demes as a means of organising, grouping and understanding the fossils of H. erectus, I address the shortcomings of the r-K dichotomy with a study of age-specific mortality. This work is then applied to patterns of encephalisation, and the energetic implications bf increasing brain size are addressed. A comparative study of two modern human populations supports the prediction that stability of environment translates into stability of growth, and these findings are applied to H. erectus. I demonstrate that H erectus exhibited a long-term trend of an increasing cranial capacity, but that this was not uniform across the species and had varying success, with subsequent energetic stress in the young resulting in high juvenile mortality in some areas. I conclude that the model of core and periphery relates to the latitude of the environment, and that H. erectus was an adaptable and flexible species with a number of strategies available to maximise survival in a range of environmental conditions.
67

'The Law of Help' : John Ruskin's ecological vision, 1843-1886

Frost, Mark January 2005 (has links)
No description available.
68

Adequação e verificação de procedimentos para determinação de mercúrio em amostras de fígado e rim de rato utilizando a técnica CV-GF AAS

SANTOS, A. E. 25 August 2014 (has links)
Made available in DSpace on 2016-08-29T15:35:36Z (GMT). No. of bitstreams: 1 tese_8105_André Eliziário dos Santos.pdf: 1636286 bytes, checksum: c6a5766e7cd00151e9c2336f4121dcd9 (MD5) Previous issue date: 2014-08-25 / O mercúrio é um elemento que ainda necessita constante monitoramento devido sua capacidade tóxica em concentrações em níveis de traço com possibilidade de contaminação e exposição por uma variedade de formas e compostos presentes no ambiente. Esse estudo possuiu como objetivo a obtenção de um procedimento simplificado e eficiente para a determinação de teores de mercúrio em tecidos de rato Wistar a partir da otimização de um método de determinação, utilizando um sistema de geração de vapor frio acoplado a espectrometria de absorção atômica com forno de grafite (CV-GF AAS). Houve a comparação entre métodos de digestão, comparação de métodos de amalgamação, otimização, verificação do método a partir da obtenção de figuras de mérito e análise de amostras de fígado e rins de ratos tratados com exposição crônica ao mercúrio. Os resultados comprovaram que o método de digestão em bloco digestor, a utilização de amalgamação por recobrimento de tubo em ouro em conjunto com rede de ouro e adição pré-análise à solução de simeticona e isopropanol apresentou os melhores resultados, com teores de recuperação médios entre 92 e 114 %, viabilizando a utilização do procedimento proposto.
69

Adequação e verificação de procedimentos para determinação de mercúrio em amostras de fígado e rim de rato utilizando a técnica CV-GF AAS

Santos, André Eliziário dos 25 July 2014 (has links)
Submitted by Maykon Nascimento (maykon.albani@hotmail.com) on 2014-12-12T19:36:28Z No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertacao.Andre Elizario dos Santos.texto completo.pdf: 1636329 bytes, checksum: 2a6ae08a2a5db20270e59c8548e445a5 (MD5) / Approved for entry into archive by Elizabete Silva (elizabete.silva@ufes.br) on 2014-12-19T18:08:25Z (GMT) No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertacao.Andre Elizario dos Santos.texto completo.pdf: 1636329 bytes, checksum: 2a6ae08a2a5db20270e59c8548e445a5 (MD5) / Made available in DSpace on 2014-12-19T18:08:25Z (GMT). No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertacao.Andre Elizario dos Santos.texto completo.pdf: 1636329 bytes, checksum: 2a6ae08a2a5db20270e59c8548e445a5 (MD5) Previous issue date: 2014 / O mercúrio é um elemento que ainda necessita constante monitoramento devido sua capacidade tóxica em concentrações em níveis de traço com possibilidade de contaminação e exposição por uma variedade de formas e compostos presentes no ambiente. Esse estudo possuiu como objetivo a obtenção de um procedimento simplificado e eficiente para a determinação de teores de mercúrio em tecidos de rato Wistar a partir da otimização de um método de determinação, utilizando um sistema de geração de vapor frio acoplado a espectrometria de absorção atômica com forno de grafite (CV-GF AAS). Houve a comparação entre métodos de digestão, comparação de métodos de amalgamação, otimização, verificação do método a partir da obtenção de figuras de mérito e análise de amostras de fígado e rins de ratos tratados com exposição crônica ao mercúrio. Os resultados comprovaram que o método de digestão em bloco digestor, a utilização de amalgamação por recobrimento de tubo em ouro em conjunto com rede de ouro e adição pré-análise à solução de simeticona e isopropanol apresentou os melhores resultados, com teores de recuperação médios entre 92 e 114 %, viabilizando a utilização do procedimento proposto. / Mercury is an element that still needs constant monitoring because it is highly toxic at trace-level concentrations, with possibility exposure and contamination by a variety of forms present in the environment. Thus, the aim of this work was adapt and verify a simple and efficient procedure for mercury determination in Wistar rat tissues using cold vapor generation, pre-concentration in graphite furnace and analysis by atomic absorption spectrometry (CV-GF AAS). They were made comparison of amalgamation methods, procedure optimization, verification of merit figures and analysis of liver and kidneys of chronically treated rat. The best results were obtained using the hot block digestion method as sample pre-treatment and gold coated tube combined with and net of gold for amalgamation. It was necessary to use dichromate, isopropanol and simeticone pre-analysis. Procedure accuracy was verified through recovery tests at five concentration (between 92 and 114 %), enabling the use of the proposed procedure.
70

Influência do baixo peso ao nascer na antropometria, composição corporal e indicadores metabólicos de crianças dos 8 aos 10 anos do município de Vitória de Santo Antão - PE

ALVES, Cristian Fernando de Siqueira 01 March 2013 (has links)
Submitted by Nathália Neves (nathalia.neves@ufpe.br) on 2015-03-04T18:11:03Z No. of bitstreams: 2 dissertacao_cristian alves_DEFINITIVA.pdf: 1182951 bytes, checksum: 13d22944e79580c62bcdbeaca77359ca (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) / Made available in DSpace on 2015-03-04T18:11:03Z (GMT). No. of bitstreams: 2 dissertacao_cristian alves_DEFINITIVA.pdf: 1182951 bytes, checksum: 13d22944e79580c62bcdbeaca77359ca (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Previous issue date: 2013-03-01 / CNPq / Objetivo: analisar a influência do baixo peso ao nascer (PN) sobre variáveis antropométricas, de composição corporal e indicadores metabólicos em crianças dos 8 aos 10 anos. Método: Um total de 99 crianças, de ambos os sexos, oriundos de escolas públicas município de Vitória de Santo Antão (PE – Brasil) foram divididas em dois grupos de acordo com o peso ao nascer (PN) (BPN < 2.500g, n = 24, e peso normal ao nascer, PNN, ≥ 2.500 g ≤ 4.850 g, n = 75). As variáveis antropométricas e de composição corporal incluem a massa corporal, altura, altura sentado, IMC, dobras triciptal, subescapular, supra-ilíaca, geminal, percentual de gordura, massa magra e gorda. Os indicadores metabólicos incluem a pressão arterial, IGF-1, peptídeo-C, colesterol, triglicerídeos, HDLc e LDLc. Resultados: Na comparação entre médias das variáveis estudadas, os grupos BPN e PNN foram iguais. Na análise de correlação bivariada, o PN se correlacionou com o IGF-1, apresentando comportamento de associações diferente nos grupos, no grupo PNN foi assinalada uma correlação positiva (r: 0,502) e no grupo BPN uma correlação negativa (r: -0,462) o que pode esta relacionado a compensação devido ao menor crescimento intra-uterino. Nas correlações por grupo, BPN e PNN, entre variáveis antropométricas e composição corporal com indicadores bioquímicos, foram assinaladas diferenças entre os grupos em todas as variáveis estudadas, exceto colesterol. Conclusão: Os grupos não apresentam diferenças médias, mas apresentam associações diferentes nas variáveis analisadas. O grupo PNN apresentou associações que seguiram padrões normativos, diferindo do grupo de BPN, especialmente nas associações dos indicadores metabólicos de pressão sistólica e peptídeo-C, com destaque para o IGF-1

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