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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.
311

Is predation performance of Pike (Esox lucius) affected by Oxazepam exposure?

Persson, Josefine January 2015 (has links)
Pharmaceutical contamination is increasing in the environment and the consequences this will bring are of growing concern. The highest contamination of pharmaceuticals can be found in aquatic ecosystems and the organisms of these systems are therefore of utmost importance to research in order to understand the ecological consequences of pharmaceutical contamination. This report will reveal the effect contamination can have on an important apex predator often found in temperate aquatic systems, the Northern pike (Esox lucius) when exposed to the psychiatric pharmaceutical Oxazepam. The predatory performance of pike was studied before and after Oxazepam exposure by monitoring how fast each pike caught three prey of roach (Rutilus rutilus), as well as observing the amount of failed predation attempts when hunting the roach. The exposed pike displayed more failed predation attempts after exposure as opposed to the control group. Furthermore it took the exposed pike longer to catch all three roach after exposure while the mean for the control group decreased. Hence, Oxazepam exposure seem to have an effect on predation performance of pike but no definite conclusion could be drawn about to which extent this affects the foraging success and thereby the survival of the pike considering the complex nature of aquatic systems. More studies are therefore needed in order to determine the full effect pharmaceutical contamination can have on complex aquatic ecosystems and more specifically on an apex predator.
312

The effect of corporate social responsibility on consumers buying decisions : An empirical study of a Swedish grocery retailer

Hellqvist, Erik, Malmström, Hans-Magnus January 2016 (has links)
Aim: The aim of this study is to analyze how CSR affects consumer behavior and how consumers are affected by, act on and behave as a result of the CSR strategies implemented by Coop grocery stores. If people are aware, have knowledge and what they know about Coop´ CSR work will be analyzed and compared with the help of survey investigations conducted in both Stockholm and Gävle. Like most big food retailers, Coop has a stated policy, but we will investigate if their CSR work makes a difference and if so - how, in the mind of the consumers. Method: A survey with 16 questions was constructed and these questions were adjusted to previous research made about CSR and its impact on the consumers and their buying decision process. The data was collected at the entrance of two Coop food retails stores, one in Gävle and the other in Stockholm. People that were at least 18 years of age were asked to participate. A total of more than 200 questioners added together in both cities were willing to participate. The data was analysed with the help of the statistical analyse program SPSS, where a regression analysis was made which we combined with a thematic analysis. Result and Conclusion: Our research indicates that consumer doesn't engage in the grocery stores work with CSR. Consumers do consider the ecological assortment but they find the price to be an obstacle when it comes to actually buying ecological products. Our study shows that there is no link between buying ecological products and loyalty towards Coop. For Coop to sell more ecological products, we suggest they should lower the prices or increase the knowledge among consumers to motivate a higher pricing. Suggestion to further research: Our study could easily be made on other food retail stores as it would be interesting to investigate if and how the end results would differ. Contribution of thesis: Our thesis gives Coop the opportunity to evaluate their CSR work and more importantly, its impact on its consumers, where suggestions are made on how to improve their CSR strategy.
313

Human obesity and Arctic adaptation : epidemiological patterns, metabolic effects and evolutionary implications

Young, Theron Kue Hing January 1994 (has links)
The objective of this dissertation is to investigate the occurrence, determinants and consequences of obesity among the Inuit people in the central Canadian Arctic, based on the Keewatin Health Assessment Study (KHAS), conducted during 1990/91 in 8 Inuit communities in the Northwest Territories (n=434 adults aged 18yr+). Data from three other surveys are included for comparison: (1) the 1190 Manitoba Heart Health Survey among 2200 predominantly Caucasian residents of the province of Manitoba; (2) the 1986-87 Northern Indian Chronic Disease Study among 704 Cree-Ojibwa Indians from Northern Ontario and Manitoba; and (3) the 1990-91 Chukotka Chronic Disease Survey among 362 Chuckchi and Inuit in coastal Chukotka in the Russian Far North. Judged by both body mass index and two skinfold thicknesses, obesity among the Inuit in the Keewatin region is as prevalent as it is in the general North American population. This is a new development over the past two or three decades, the result of rapidly changing physical activity, diet and other lifestyles. Obesity is more prevalent among women, among whom there is also a higher prevalence of central fat patterning. Age, education and non-smoking status (females only) are consistently identified as independent predictors of various obesity indices on multivariate analysis. While better educated men are more likely to be obese, the relationship is reversed in women, possibly due to the different sex roles and their associated stress levels in a rapidly acculturating and modernizing society. When different categories of obesity indices are compared, there is a consistent pattern of an increasing trend in blood pressure and one or more of the lipids but no significant change in glucose or insulin level. This observation distinguishes the Inuit and Chukchi from Caucasians and Amerindians. Even where a relationship exists, as with triglycerides and HDL-cholesterol, the magnitude of response is also lower among the Inuit. The differential effect of obesity on glucose, blood pressure and lipids in Inuit compared to non-Inuit suggests a type of selective insulin resistance, the underlying mechanism of obesity and several chronic diseases. The Inuit metabolism reflects their almost exclusive diet of fat and proteins. Apart from its public health importance, the study of Inuit obesity can shed some light into issues related to the peopling of the Americas: are the Inuit "exempt" from the "New World syndrome", and can the "thrifty genotype" explain the differential occurrence of diabetes among Arctic and Subarctic hunter-gatherers? It provides an opportunity to elucidate fundamental questions relating to the interaction of genetic and environmental factors in disease causation and distribution.
314

Bridging the ecological knowledge and knowledge-action gaps: a utopian vision for education in Manitoba

Henderson, Matthew 12 September 2016 (has links)
This thesis seeks to advance a curriculum which provides learners with educative experiences required to promote an ecological literacy. This particular type of literacy enables individuals and communities to understand their connectedness to all systems, to appreciate the finite carrying capacity of the planet, to predict consequences of human activity, and to ultimately create sustainable communities through action, or praxis. The proposed curriculum is a vision of public education in Manitoba, borrowing examples of experiences throughout the world which are then adapted to meet the ecological, social, and political realities of this province. It is a utopian-inspired curriculum as it seeks to shed current restraints imposed by contemporary educational practices in Manitoba. By removing certain constraints, this philosophical inquiry can then be used to provoke a dialogue as to how we might transform learners into agents of social and ecological change. / October 2016
315

Integration of Traditional Chinese Building Concepts with Contemporary Ecological Design Considerations: A Case for High-rise Wood Buildings

Zhuo, Xiaoying, Zhuo, Xiaoying January 2016 (has links)
The ecological design considerations are focusing on the built environment and the living process of the building. It considering the environment impact in designing building, and integrating ecological responsive design methods. While the traditional Chinese building shared the same design philosophy. Our ancestors are really concerning the connection between their living space with the broader environment, not only in the time they occupying the building, but also when they construct and demolish it. They use the word "harmony" to describe this relationship with the environment, and consider it as the high-quality pursuit of life. Wooden building has been a major building type in China for thousands of years, however, over 40 thousand traditional Chinese building has been demolished in the past 30 years, most of them are wooden buildings. Since the steel, concrete and other emerging materials has become the major materials for the modern building, wooden building seems to step down from the stage of history. Not until in recent years, wooden building come into people’s view again, it’s increasingly appeared in all over the world and take part in a major role in mordent architecture. Since the wood is a sustainable and renewable building material, and a good carbon sink, it is more environmental friendly than steel, concrete or some other building materials. The wooden building has a great potential to discover its ecological benefits and as a carrier of traditional Chinese culture. In seeking the development of wood as a building material, and the future of sustainable buildings, I integrate the theory with practice that human population is growing rapidly, the high-rise wooden building might be a best solution for this quest. I expect to explore the application of wood in high rise building’s envelope and structure, integrate the wood with other material to expand its performance, emotionally and reality connect the traditional Chinese culture and people’s memory of the land to the present day.
316

An Ecological Design Approach to Wastewater Management

Lozano, Sacha 01 January 2008 (has links)
Global water depletion and unsustainable food production systems represent two iconic crises of our time. These two crises have important themes in common, referring to basic human needs and the way we interact with landscapes in order to satisfy them. But they are also closely related to the way we produce and dispose wastes in our current societal organization. Insufficient, or inadequate, sanitation and waste management practices continue to undermine not only human well-being, but the entire planet’s ecological integrity, on which humans depend. An ecological design approach to manage human waste invites to learn how to participate more harmoniously within the planet’s recycling of matter, using renewable energy sources and mimicking nature’s low entropic states to maintain the life-support systems that we and our economies are part of. This thesis is an in-depth exploration of such an approach, and an attempt to integrate several elements from ecology, engineering, economics, and community development, around issues of water quality, sanitation and waste management in Latin America. As a whole, the thesis explores how can this transdisciplinary approach translate into coherent, feasible, and concrete action, providing appropriate solutions for sanitation, in ways that are effective and viable on a long term, for Latin American rural communities. Three different papers address different dimensions of the problem, focusing on domestic wastewater and human excreta, as a type of waste of major importance to ecological integrity, public health and economic development. Two of the papers are case studies, carried out at two different rural communities in South West Colombia; one of them focuses on technological and ecological aspects, and the other focuses on social and economic considerations, for a multifunctional-ecological waste management. In the first paper I present an overview of the sanitation problem in Latin America, and the opportunities and challenges of managing waste with an ecological and multifunctional perspective. More specifically, this papers attempts to provide a sound conceptual framework for managing wastewater (sewage) as a valuable resource, in a way that: 1) is affordable –or even profitable– by small communities in developing countries; 2) is safe to the environment and to public health; and 3) provides opportunities for recycling nutrients and organic matter (available in wastewaters), to restore and protect water and soil resources, while enhancing rural livelihoods in tropical agroecosystems. The second paper evaluates the performance and feasibility of an experimental, solar-energy-based, wetland mesocosm, as a complementary aerobic unit to enhance anaerobic wastewater treatment, in a rural locality of the Cauca Valley in Colombia. In the third paper I explore the integration between ecological design and community-based solutions to sanitation, and discuss opportunities and challenges of implementing ecological waste management in the particular bioregional and socioeconomic context of a proposed ecological-low-income co-housing project, in another rural community of Colombia. In doing this, several arguments are presented to support the idea that assuming the responsibility of managing its own waste can be a powerful and transformative experience for a community to fundamentally change its perspective and understanding of its place within the planet. Furthermore, managing waste can be an integrative force linking economic, social and environmental considerations, and favoring human-scale development, genuine progress, and self-reliance in a community. In its broadest level my research aims at reviewing and questioning the very notion of “waste” and the articulation between humans, nature, and technology within that context.
317

Global Ocean Futures : Governance of marine fisheries in the Anthropocene

Merrie, Andrew January 2016 (has links)
This PhD thesis provides an analysis of how an adaptive governance approach can be applied to address existing and emerging challenges in global governance with a focus on marine, wild-capture fisheries. All the papers share a coupled social-ecological framing while providing diverse but complementary perspectives. Paper I provides a lens through which it is possible understand the types of interactions that link social and ecological components of fisheries systems at the global scale. The key result of this paper was the development of a marine social-ecological framework to guide future modelling and scenario analysis. Paper II describes the process of emergence and spread of new ideas in marine governance using Marine Spatial Planning as an illustrative case study. The study shows how governance innovations may contribute to resolving the mismatches between the scale of ecological processes and the scale of governance of ecosystems. A key finding of the paper is the identification and explanation of the mechanisms by which informal networks of actors are able to influence the emergence and spread of new governance forms from the local to the global scale. Paper III focuses on governance of ocean areas beyond national jurisdiction. The key finding from this paper is the urgent need for existing and emerging governance institutions to build capacity for responding to the challenges facing governance of marine fisheries. These challenges arise from unexpected shifts in markets, technology and society. Paper IV develops a set of four imaginative but plausible ‘radical’ futures for global fisheries drawing on trends compiled from a diverse evidence base. The four resulting narratives aim to act as lenses for engaging debate and deeper reflection on how non-linear changes in technology and society might radically shift the operating context and core assumptions of fisheries governance in the future. These papers make a novel contribution to Sustainability Science through their focus on 1) the conditions for, and mechanisms of emergence of diverse and divergent governance forms, 2) the role of agency in complex actor settings, 3) the need for governance institutions to not only deal with, but also be able to anticipate surprise, and 4) the development of scenarios of marine social-ecological futures using a creative and rigorous narrative approach. / <p>At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 4: Manuscript.</p>
318

Wilderness Women: Embodiment in Nature

Cordell, Tami 08 1900 (has links)
Virginia Woolf makes clear in her book A Room of One's Own that "[A] woman must have money and a room of her own if she is to write…." This statement extends to all endeavors by women, including sport. The gap between men and women's sports is not bridged by monetary compensation. The domination of women exists in conceptual ideals and how those are expressed through our roles in this world. I use Val Plumwood's ecological feminist theory to expose the blatant masculinity imposed upon sport. I shall argue that sport is an arena of constant struggle over basic social conceptions of men and women. My endeavor is to implore traditionally masculine territory, and show sport as the domain of no single gender, but a field of simplicity and cooperation.
319

Colonisation and development of salt marsh in the Dee estuary, NW England : integrating large-scale pattern and small-scale ecological process

Huckle, Jonathan Mark January 2000 (has links)
The Dee estuary, one of the most important British estuaries in terms of size and conservation value, has been subject to extensive colonisation and development of intertidal mudflats by salt marsh vegetation. In the last century, acceleration of this process has been attributed to the ability of Spartina anglica C.E. Hubbard to colonise bare sediment. The research in this thesis aims to investigate the ecological patterns and processes involved in the development of salt marsh vegetation. These have been examined using a large-scale approach involving remote sensing techniques and a small-scale approach to examine ecological processes at the level of the individual plant and species. Large-scale temporal patterns in the distribution were investigated by analysing a sequence of monochrome aerial photographs dating from 1955 to 1997. At the marsh apex, initial rapid colonisation was followed by a decreased rate of expansion and a reduction in the pioneer zone. This suggested a steepening of the marsh elevation gradient, which is interpreted as the marsh approaching its natural limit of expansion. The rate of salt marsh expansion was consistent across the time sequence for the second target area, a cross-section of the marsh gradient, but with S. a«g/zca-dominated colonisation of mudflats changing to colonisation by a pioneer community co-dominated by S. anglica and Salicornia europaea. Large-scale spatial distribution patterns were further investigated using multispectral remote sensing data from 1997. Radiometric data were used to define the spectral characteristics of the major types of salt marsh vegetation. Airborne Thematic Mapper data were used to classify the reflectance data from the whole marsh to determine the spatial distribution of plant communities based on their spectral characteristics. Mapping of these communities provided a baseline that will be a useful tool for future management of the salt marsh. An experimental approach was used to examine the role of abiotic and biotic factors on the growth and interactions between S. anglica and Puccinellia maritima (Huds.) Parl. In two series of competition experiments, P. maritima exerted a one¬way effect over S. anglica. The intensity of this interaction was increased in environmental conditions favourable to P. maritima, and was greater in terms of above-ground than below-ground biomass. In both experiments, S. anglica exhibited a disproportionate reduction in below-ground competitive interaction in abiotic conditions less favourable to P. maritima. A corresponding increase in rhizomes suggested that this is a potential mechanism by which S. anglica may evade competitive neighbours at low marsh elevations. An appreciation of the importance of scale has led to a multi-scaled and holistic view of the ecological process of salt marsh colonisation and development. Integration of both large and small-scale approaches has provided valuable information on the ecological patterns and processes, and has important implications for current and future management of salt marsh in the Dee estuary.
320

Investigating the molecular basis of adaptation and speciation in divergent populations

Smith, Gilbert January 2013 (has links)
The creation of biodiversity involves the evolution of new species. Recent trends in the study of speciation have increased the emphasis on the role of ecology in adaptation and the evolution of reproductive isolation. This includes examining the relative contributions of different types of selection, the role of gene flow and the genomic changes that occur during ecological speciation. The search for speciation genes continues, however our growing knowledge of how the genome translates into phenotypes means we should now consider a broader molecular basis of speciation, which includes genetic, transcriptomic and potentially epigenetic variation that contribute to phenotypic variation. This thesis addresses the molecular basis of speciation by using three different complementary methods to examine the early stages of ecological speciation and the evolution of premating reproductive isolation between two incipient species of the cactophilic fly, Drosophila mojavensis. First, the genetic basis was examined through the sequencing of two candidate genes underlying reproductive isolation (Chapter 2). Second, the historical biogeography of population divergence was uncovered using multiple sequenced loci (Chapter 3). Lastly, gene expression across the whole transcriptome associated with phenotypic plasticity and mating success was assessed (Chapter 4). Further, the role of epigenetic imprinting in the population divergence of a freshwater fish, Girardinichthys multiradiatus, was examined through sequencing of a well known gene involved in sexual conflict (Chapter 5). These studies find that uncovering the genetic variation underlying speciation is difficult, especially when there is extensive phenotypic plasticity. Further, gene expression plasticity may play an important role in the evolution of premating isolation, and this includes a role for epigenetic mechanisms of gene expression. Additionally, it is important to assess the demographic scenario of population divergence to put into context the ecological and functional data on divergent groups. Through these studies this thesis examines the genetic, expression and epigenetic variation associated with on-going population divergence, and emphasises the need to consider the potential role of the full range of gene expression changes during ecological speciation.

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