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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.
1

Honouring the journey to the eighth fire: educating to create common-unity

McLeod, Kristine Louise 19 September 2016 (has links)
Honouring the Journey to the Eighth Fire: Educating to Create Common-Unity Many directions people turn to today there is dissension: bombings, riots, shootings, famine and even genocide. There is an increasing awareness that change is required to create a more peaceful world, but how can we create common-unity and integrate it into educational systems? This narrative enquiry research explores the ways Maxwell International Baha’i School (MIBS) attempted to create an inclusive community that was founded on the principle of the oneness of humanity. It was through MIBS’s conscious attempt to create community that people felt accepted, safe and learned to connect. This research, through a focus group of primary stakeholders, explored the way community was intentionally built. The findings in this research revealed that from its inception, MIBS accepted diversity as a means to create unity, leading to members feeling a sense of belonging, connected to a greater purpose and a desire to serve humanity. With a conscious desire, schools could replicate this type of inclusive community. It is with this knowledge that I have been asked to create a more inclusive community at my current school. Education for a globally inclusive world must not be merely a separation and honouring of diversity, but must instead weave together the diverse elements through ritual and ceremony in a manner that creates an integrated tapestry. It is time to consciously and fully educate people to see that “the earth is but one country and mankind its citizens.” (Baha’u’llah, 1990, p. 346) / Graduate / mcleod.kristy@gmail.com
2

Archaea at the El Tatio Geyser Field : community composition, diversity, and distribution across hydrothermal features and geochemical gradients

Franks, Megan A. 11 July 2012 (has links)
Methanogenesis, a metabolic pathway unique to Archaea, is severely inhibited by the reduced form of arsenic (As). Despite this inhibition, methanogenic Archaea are present in some hydrothermal features at the El Tatio Geyser Field (ETGF), a high-arsenic site with 100+ hydrothermal features, including boiling pools, geyers, fumaroles, and springs. The ability of methanogenic Archaea and other microorganisms to withstand elevated arsenic concentrations, and a variety of other extreme environmental conditions at ETGF, may be due to unique adaptations or syntrophic relationships with other microorganisms. ETGF is situated in the Andes Mountains at an altitude of ~4300 meters. UV radiation is elevated in this region and air temperatures fluctuate widely. Most hydrothermal waters discharge at ~85˚C, the local boiling point, and rapidly evaporate due to the arid climate. This concentrates hydrothermal salts and metals, including arsenic (As) and antimony (Sb). Additionally, dissolved inorganic carbon (DIC) concentrations are extremely low in most features and may limit life. Water chemistry analyses done for this study show variability in dissolved constituents between features that are consistent over time. Variations may be due to the source or residence time of waters, and differences in chemistry could be responsible for the presence or absence of methanogenic Archaea at hydrothermal sites. The overlying control on microbial diversity and community composition may be water geochemistry, and potentially specific constituents. The goals of this study were to detect novel microbial taxa at ETGF, including novel methanogens, as well as to document microbial community composition at select hydrothermal features. The distribution and diversity of microorganisms at each feature was analyzed phylogenetically and within an ecological context in order to determine physicochemical and biological controls on community composition. Additionally, a model methanogen was used in laboratory analyses to determine how concentrations and oxidation states affected growth and methane production. This methanogen, Methanothermobacter thermautotrophicus, is found at ETGF, Yellowstone, and other hydrothermal fields, and thrives in high-temperature environments. MPN (most probable number) analyses show that culturable biomass from multiple sites contain metabolically active methanogens. These results support the biogenicity of dissolved methane detected in the field. 16S rRNA surveys of Archaea at four sites show that Archaea are diverse, and archaeal community composition varies across features. Phylogenetic tree construction indicates that Archaea from ETGF group together, suggesting that the isolation and broad environmental constrains on ETGF have some control on phylogenetic diversity. Laboratory analyses of As and Sb concentrations on M. thermautotrophicus suggest that Sb may decrease the inhibition of methanogenesis by As by preventing the formation of As(III) from As(V). Statistical analyses correlating microbial community composition and structure to physicochemical parameters show that archaeal and bacterial communities relate to different variables; with Bacteria correlating to water temperature, and Archaea correlating to dissolved constituents such as hydrogen gas and sulfate. / text
3

A Biophysical Analysis of Forest Diversity Patterns at Mt. Kasigau, Kenya

Henkin, Michael Albert 19 August 2013 (has links)
No description available.
4

15N stable isotope probing of pulp and paper wastewaters

Addison, Sarah Louise January 2008 (has links)
Stable isotope probing (SIP) is an established technique that can be applied to identify the metabolically active micro-organisms within a microbial population. The SIP method utilises an isotopically-labelled substrate and PCR techniques to discern the members of a microbial community that incorporate the isotope into their DNA or RNA. The current literature gap around using 15N isotopes with RNA-SIP offers real potential and advantages for targeting and identifying active members from mixed communities involved in global biogeochemical nitrogen cycling. This study specifically investigated whether nitrogen based compounds can be used as substrates in RNA-SIP methodologies and whether they can in turn be used to probe mixed community environments known to be actively fixing nitrogen. The nitrogen-limited systems targeted represented an ideal opportunity to assess the suitability of 15N-RNA-SIP approaches due to their known high nitrogen fixation rates. Identifying these nitrogen-fixing bacteria could provide a better representation analysis of the community, leading to an improved prediction on how to manage and optimise the treatment performance of target waste systems and to exploit the unique bioconversion properties of these types of organisms. Initially, the project undertook methodological proof of concept by using a soluble nitrogen source, 15NH4Cl, to label the RNA of Novosphingobium nitrogenifigens and a mixed microbial community. Successful separation of the 14N- (control) and 15N-RNA was achieved for both pure and mixed communities using isopycnic caesium trifluoroacetate (CsTFA) gradients in an ultracentrifuge. The usefulness of this technique to identify active diazotrophs in real environmental samples was tested using a nitrogen-fixing community from a pulp and paper wastewater treatment system. After growing the mixed culture with 15N2 as the sole nitrogen source, the labelled RNA was extracted and fractionated using isopycnic centrifugation in CsTFA gradients. The community composition of the active nitrogen-fixing community in the 15N2 enriched fraction was analysed by establishing a 16S rRNA gene clone library containing over 200 members. These were analysed by comparison with published sequences and by phylogenetic analysis. It was found that the more isotopic label substrate incorporated, the further the buoyant density (BD) separation between 15N- and 14N-RNA. Novosphingobium nitrogenifigens gave an average BD shift of 0.03 + 0.004 g ml-1 (95.0 atom % 15N) with 15NH4Cl. For mixed communities the average BD shift was 0.02 + 0.004 g ml-1 (80.0 atom % 15N) with 15NH4Cl and 0.013 + 0.002 g ml-1 (32.6 atom % 15N) when using 15N2. Clone library analysis of 16S rRNA genes present in the enriched 15N-RNA fraction of the mixed community was shown to consist of a diverse population of bacteria as indicated by a Shannon Weaver index value of gt;2.8. Three dominant genera (Aeromonas, Pseudomonas and Bacillus) were identified by comparison with published sequences and phylogenetic analysis. Many other groups not known as archetypal nitrogen-fixing bacteria were also identified, demonstrating that 15N2-RNA-SIP provides a useful tool for the identification of important and previously unknown contributors to nitrogen fixation in a range of environments. Overall, this project has established that nitrogen based RNA-SIP is a powerful tool that can be used successfully and reproducibly with both pure and complex mixed microbial communities to study active diazotrophs in environmental samples.
5

Competing realities, diverse needs : an inter-disciplinary approach to religious engagement with HIV prevention and care

Morris, Margaret January 2012 (has links)
The World Health Organisation/ UNAIDS and the UK's HIV-related public health policies are premised on universal access to information, treatment and care. With a focus on wider determinants of health, such rights-based approaches and their associated commitment to consistent HIV prevention messages and effective care include also a requirement to be respectful of and sensitive to religio-cultural beliefs and practices. There is evidence that access to HIV information and care can be restricted by the moral codes, beliefs and teachings which determine some religious responses to HIV, those, for example, which address issues of sexuality and gender, identity and belonging, authority and power. With a particular interest in a UK context of religio-cultural diversity, this study asks whether existing strategic public health responses to HIV prevention and care are adequate to the multiplicity of psychosocial realities and needs of a diverse community. The study follows comparative interpretative approaches and draws on a range of theoretical perspectives, primarily those of sociology, anthropology and psychology. It identifies the potential for dialogical compatabilities between public health practice and practical theology. Gathering and analysing data and discourse this interdisciplinary, qualitative investigation examines religion-informed responses to HIV prevention and care. With a small-scale localised study positioning the content and authority of religious belief on responses to HIV prevention and care in a UK Midlands city of high religio- cultural diversity, the primary and secondary data are 'grounded' in the experience of a local community. In its tracing of the multiple realities of HIV in contexts of global and local religio - cultural diversity, the study finds that global dimensions of HIV touch the local in unavoidable and diverse ways Religion-defined identity and belonging are valued by people affected by HIV and the communities of which they are part, but the stigmatizing impact of HIV, often reinforced by religious beliefs and teachings, generates anxieties about the disclosure of a diagnosis, the initiation of open discussion and access to HIV information and care. Constraints on the access of sexual minorities, young people and women can raise particular concern. In situations of diverse need and contested reality quests for coherent meaning, identity and belonging confront a public health preference for consistent HIV health messages and for accessible and effective programmes of HIV information, support and care. The study evidences diverse and often competing perspectives on HIV and highlights the need for health and social care services and religious groups to have greater awareness of the extensive complexities which the realities of diversity bring to HIV prevention policy design and service delivery. Complexity theory and practical theology inform a new and integrative model for theological, epidemiological and public health partnering through which the inadequacies in both religion-informed responses to HIV and public health HIV prevention and care policy and service delivery can be addressed.
6

Avian malaria in the montane tropics

Daly, Benjamin January 2013 (has links)
Understanding the unequal distribution of life on earth is a fundamental goal of ecology and evolutionary biology. Past efforts to explain large-scale patterns in diversity have tended to focus on two broad classes of explanation, one invoking the importance of abiotic factors (i.e. climate and vegetation) and the other biotic (i.e. competition); but neither has proven entirely adequate. Parasites are a major but poorly understood component of life that may offer some answers. Yet despite widespread theoretical support and some empirical evidence, the role of parasites in explaining patterns in the diversity, distribution, and abundance of species remains largely untested in natural communities. In this thesis I use a mega-diverse elevation gradient of birds as a model system to study the role of avian malaria in explaining these macroecological patterns. In the first data chapter I tested the extent to which patterns of infection across species is predictable. I found that the effects of host ecology and environment were weakly related to infection prevalence and were not consistent across different malaria lineages. Instead, I show that hosts coexisting with many close phylogenetic relatives consistently experience higher infection than evolutionarily distinct host species. In the second chapter I tested if parasite sharing may help explain these observed relationships and show that parasite sharing among host pairs declines with the time since divergence. Spatial contiguity between host pairs was also positively associated with parasite sharing. In the third chapter I tested how infection prevalence varies across species ranges in accordance with expected variation in host abundance. I show that birds are more likely to be infected at the centre of their elevation range, where host abundance is expected to be highest. Intriguingly, I also found that the incidence of host infection is unrelated to the position within the geographic range of the parasite. In the fourth data chapter, I tested whether parasites may regulate diversity by limiting geographic ranges of their hosts through ‘apparent competition’ in which a non-lethal parasite in a primary host, may be lethal in a secondary host. In support of this, I found that more observed bird ranges end at parasite infection zones than would be expected by chance. Taken together, my results suggest that parasites may play a major role in shaping patterns in the distribution and diversity of species, over both ecological and evolutionary scales. This is likely to arise and be maintained by host parasite interactions in which distantly related hosts are less likely to be infected by local parasites than close relatives, thus promoting the build up of diversity locally. On the basis of my analyses, I conclude that across montane elevation gradients in birds, and across diversity gradients more generally, parasites are likely to play a crucial role in the origin and maintenance of high biological diversity.
7

Bioassessment and the Partitioning of Community Composition and Diversity Across Spatial Scales in Wetlands of the Bonneville Basin

Keleher, Mary Jane 13 July 2007 (has links)
The Bonneville Basin encompasses an area that was covered by ancient Lake Bonneville and which today lies within the Great Basin province. The Bonneville Basin is distinguished geologically by its characteristic parallel north-south mountain ranges that are separated by broad, alluviated desert basins and valleys. Benches and other shoreline features of ancient Lake Bonneville prominently mark the steep, gravelly slopes of these ranges. Numerous artesian desert springs are present at the base of the mountains and in the valley floors that form various sizes of both isolated wetlands and wetland complexes. Many these wetlands are some of the most unique and currently some of the most threatened wetlands in the United States. Several aquatic species and communities have maintained an existence as relict populations and communities in these wetlands since the receding of Lake Bonneville over 10,000 years ago. For example, Hershler has described 58 previously undescribed species of hydrobiid snails, 22 of which are endemic to single locations. Like hydrobiid snails, numerous other species, such as the least chub, Iotichthys phlegethontis and the Columbia spotted frog, Rana luteioventris, depend on these wetlands for their continued existence, many of which are already imperiled. The continued decline and loss of these wetlands would further push many of these species toward endangerment and/or extinction. Several factors have already eliminated or altered many of these habitats including capping and filling,water depletions, agricultural practices, livestock grazing, and introduction of nonnative species. In recent years, the significant loss and degradation of wetlands resulting in sensitive species designations have provided impetus for resource agencies to develop and implement management plans to conserve and protect these vital ecosystems. One problem facing appropriate management is the lack of biological information for determining which wetlands should receive protection priorities based on the presence of viable, functioning characteristics. The purpose of this dissertation project was to obtain biological information needed to support defensible decisions concerning conservation, protection, acquisition, restoration, and mitigation of the artesian springs in the Bonneville Basin. The primary objectives of this project were to 1) Develop bioassessment procedures for artesian wetlands of the Bonneville Basin using macroinvertebrates and 2) Determine patterns of community composition and diversity for macroinvertebrates and metaphyton algae at multiple scales in Bonneville Basin artesian wetlands.
8

Environmental DNA Detection and Population Genetic Patterns of Native and Invasive Great Lakes Fishes

Snyder, Matthew Robert January 2019 (has links)
No description available.
9

Patterns and processes of exotic plant invasions in Riding Mountain National Park, Manitoba, Canada

Otfinowski, Rafael 10 September 2008 (has links)
Invasive exotic species threaten the biodiversity and function of native ecosystems. Existing models, attempting to predict and control successful invaders, often emphasize isolated stages of in their life history and fail to formalize interactions between exotic species and recipient environments. In order to elucidate key mechanisms in the success of select invaders, I investigated the role of dispersal, establishment, proliferation, and persistence in their threat to natural areas. Focusing on Riding Mountain National Park, Manitoba, Canada, I integrated the native climatic range and biological traits of 251 exotic vascular plants reported inside and outside the park. Based on their climatic range in Europe, 155 among 174 exotic plant species absent from the Park were predicted to establish within its boundaries; among these, 40 clonal perennials were considered the highest threat to the Park’s biodiversity. Focusing on smooth brome (Bromus inermis Leyss.), a Eurasian perennial, threatening the structure and function of native prairies throughout the Great Plains, I extended my research to investigate the role of dispersal, establishment, proliferation, and persistence in characterizing its threat to the endemic diversity of northern fescue prairies, protected within Riding Mountain National Park. Patterns of smooth brome invasions were contingent on the type of propagules dispersed. The shallow dispersal gradient of individual florets combined with the steeper gradient of panicles and spikelets suggested that smooth brome is capable of simultaneously invading along dense fronts as well as by establishing isolated foci. While low correlations between the number of dispersed seeds and their recruitment suggested post-dispersal transport, seedling establishment remained contingent on prairie diversity. Seedling biomass increased with declining plant diversity, however, its impact depended on the availability of soil nitrogen. As a result, disturbed areas, preserving the root function of native plants, resisted smooth brome establishment. Even though low nitrogen contributed to a decline in seedling biomass, physiological integration between ramets facilitated their vegetative proliferation in low resource environments. Despite its rapid establishment and proliferation, smooth brome productivity declined at the center of invading clones. Although field and greenhouse observations failed to implicate soilborne pathogens, reasons for the observed decline remain unresolved. My research demonstrates that while Riding Mountain National Park and other natural areas in western Canada will continue to be impacted by exotic plants, integrating key stages in their life history provides an important conceptual framework in predicting their threat to natural areas and prioritizing management. / October 2008
10

Patterns and processes of exotic plant invasions in Riding Mountain National Park, Manitoba, Canada

Otfinowski, Rafael 10 September 2008 (has links)
Invasive exotic species threaten the biodiversity and function of native ecosystems. Existing models, attempting to predict and control successful invaders, often emphasize isolated stages of in their life history and fail to formalize interactions between exotic species and recipient environments. In order to elucidate key mechanisms in the success of select invaders, I investigated the role of dispersal, establishment, proliferation, and persistence in their threat to natural areas. Focusing on Riding Mountain National Park, Manitoba, Canada, I integrated the native climatic range and biological traits of 251 exotic vascular plants reported inside and outside the park. Based on their climatic range in Europe, 155 among 174 exotic plant species absent from the Park were predicted to establish within its boundaries; among these, 40 clonal perennials were considered the highest threat to the Park’s biodiversity. Focusing on smooth brome (Bromus inermis Leyss.), a Eurasian perennial, threatening the structure and function of native prairies throughout the Great Plains, I extended my research to investigate the role of dispersal, establishment, proliferation, and persistence in characterizing its threat to the endemic diversity of northern fescue prairies, protected within Riding Mountain National Park. Patterns of smooth brome invasions were contingent on the type of propagules dispersed. The shallow dispersal gradient of individual florets combined with the steeper gradient of panicles and spikelets suggested that smooth brome is capable of simultaneously invading along dense fronts as well as by establishing isolated foci. While low correlations between the number of dispersed seeds and their recruitment suggested post-dispersal transport, seedling establishment remained contingent on prairie diversity. Seedling biomass increased with declining plant diversity, however, its impact depended on the availability of soil nitrogen. As a result, disturbed areas, preserving the root function of native plants, resisted smooth brome establishment. Even though low nitrogen contributed to a decline in seedling biomass, physiological integration between ramets facilitated their vegetative proliferation in low resource environments. Despite its rapid establishment and proliferation, smooth brome productivity declined at the center of invading clones. Although field and greenhouse observations failed to implicate soilborne pathogens, reasons for the observed decline remain unresolved. My research demonstrates that while Riding Mountain National Park and other natural areas in western Canada will continue to be impacted by exotic plants, integrating key stages in their life history provides an important conceptual framework in predicting their threat to natural areas and prioritizing management.

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