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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

A Spatial Analysis of the Impact of Development on Wetland Habitat in Mount Pleasant, South Carolina

Medlin, Jenna 01 April 2004 (has links)
In response to growing concerns over wetland habitat loss and the associated impact on water resources, federal and state legislation has been enacted to protect vulnerable wetland habitats from the impacts of humans. In order to examine the efficacy of current coastal resource policy and its implementation, a study was conducted in Mount Pleasant, South Carolina, a coastal city of the Atlantic, focusing on the quantification of wetland habitat change over time within a specific area of interest. The study incorporated an assessment of the effects of escalating population pressures and subsequent urban development on local wetland habitats due to the inherent threat of habitat degradation resulting from negligent development practices. The research methodology included a series of stakeholder interviews conducted within the Mount Pleasant community in order to define the key players who shape coastal resource policy formation, implementation, and enforcement. Further, a spatial analysis examined land use change over time. A historical record of regional land use derived from remotely sensed satellite imagery enabled the measurement of land use change over time. The results of a change detection analysis indicate an acceleration of wetland habitat loss in the second decade chosen for analysis in spite of strengthened coastal resource regulations enacted within the same time period. These results support a need for improved regulatory enforcement strategies and utilization of conservation-driven development practices.
62

Water Quality Assessment in Cypress Creek Nature Preserve

Flora, Jason 01 May 2003 (has links)
Swamps are unique ecological communities that provide many valuable ecosystem services. In Kentucky, however, many swamps were altered by cypress removal and land development in their watersheds. Cypress Creek Swamp, which lies near Paducah in western Kentucky, is a good example of a swamp whose ecological integrity may be threatened by past and current nearby land use practices. This study was conducted to assess the water quality and macro- and microinvertebrate communities in the swamp. Three sites were monitored for temperature, dissolved oxygen, pH, specific conductivity, depth, phosphorus measured as orthophosphate, nitrite (NO2") and nitrate (NO3", NOx collectively), and ammonia nitrogen (NH3). The temperature, dissolved oxygen, NH3 and NOx concentrations changed with the growing season, but pH demonstrated little variability among the sites. The specific conductivity and phosphorus levels were highly variable. Principal component analysis (PCA) indicated no significant difference in microinvertebrate taxa identified among locations or through time. A oneway analysis of variance (ANOVA) indicated no significant difference in macroinvertebrate population total densities between locations (P = 0.847), and a oneway analysis of variance (ANOVA) showed no significant difference in microinvertebrate population total densities among locations (P = 0.153) or through time (P = 0.294). As development continues in the watershed, this work provides an important baseline for future water quality monitoring in the preserve.
63

The Progression of Recycling in Bowling Green, Kentucky

Marklin, Susan 01 December 2001 (has links)
Recycling is an important issue when dealing with solid waste. It keeps many tons of garbage out of our landfills and prolongs landfill life. Although many people in the Bowling Green area participate in the mandatory recycling program, there are still many who do not. The number of people who participate in the program has steadily grown over the past five years; however, there are still many people who need to get involved. This research argues that much effort has been put into recycling in recent years at the global, national, and local level. However, it also argues that even more remains to be done, especially at the local level. I have conducted a sixty-day field study of both commercial and residential sites in the Bowling Green area. This field study shows that everyday there are many recyclables as well as other items placed into the trash that need not go into our garbage. This field study will also show that there are some very wasteful industries in Bowling Green. They are throwing food items away that could be used to help hungry people in the Bowling Green vicinity. It will also show that some industries, such as Houchens Markets, throw recyclables such as cardboard into their dumpster even though they have a cardboard bailer on the premises. This research will also offer reasons for people choosing not to use the recycling program. I have conducted a survey of one hundred people who live in the Bowling Green area. This survey shows that one reason some people do not use the recycling program is that they feel they are forced to do it. A few people went so far as to say that they feel the recycling program is a form of communism, and they will not use the program for that reason. I have also included entire matrices from both the residential and commercial study areas. These matrices list every item that I found during this field study. I have also included some recommendations for increased participation in the recycling program, as well as some suggestions for the industries as to how they could dispose of their unwanted food items and help the general public at the same time. I wish people could see the Earth the way that I see it. If they could, they wouldn't even think about recycling: it would become a part of their everyday routine.
64

Environmentalism in the United States: An Evolving Perspective

Snow, Mary 01 May 1996 (has links)
The purpose of this study is to investigate environmentalism in the United States. The dimension of perspective receives considerable attention. The prevailing perspective by a society regarding the importance of the health of the natural world greatly influences the degree of support of environmental organizations, environmental policy, as well as the direction charted for the future of that society. The perspectives of the Native Americans and the dominant European cultures which arrived in North America are presented and contrasted. It is supposed that the perspective which prevails in the United States regarding the importance of the natural world is evolving. During the eighteenth and nineteenth centuries, Manifest Destiny and the American Industrial Revolution exacted a steep cost from the nation's natural resources. Previously perceived as "raw materials," today the unmanipulated environment is viewed in terms of its recreational, aesthetic, ecologic, and spiritual worth. This evolving perspective is demonstrated qualitativelythrough case studies featuring methods of sustainable agriculture, by an ecological restoration project, and by grassroots eco-poltical activism. The changing perspective is quantified by measuring the growth of some of the nation's leading environmental organizations. It is hypothesized that those organizations have experienced significant growth over the study period, or from 1980-1994. It is concluded that there has been phenomenal growth of the leading environmental organizations during the study period. The prevailing perspective by the citizens of the United States is indeed evolving toward a view that is more sustainable since the missions of the nation's leading environmental organizations are endorsed by the financiers of those organizations Environmentalists, now more than ever, must remain encouraged and vigilant in order to increase the chances that the newly evolved perspective will become policy. Increased participation in the political process is facilitated by the personal computer which allows both the monitoring of environmental voting records of the individual Members of Congress while making those legislators accessible by electronic mail systems. Finally, the optimal sustainable perspective is reflected in the words of Ralph Waldo Emerson. Each step toward the ultimate environmental perspective indicates genuine progress for America.
65

Ecology, Economy and Ecotourism: Sustaining People and the Environment

Snow, Richard 01 May 1996 (has links)
Tourism is the world's largest industry. The fastest growing segment of the travel and tourist trade is ecotourism. The concept of sustainable development insists that humans cooperate with nature in the search for an ecological economy which can support present and future populations. Ecotourism attempts to attain this elusive goal by preserving ecosystems while generating revenue for local communities. In this study, the researcher examines the positive and negative effects of ecotourism on people, culture, and landscape. An analysis of tourism data seems to suggest that developing countries, which are popular ecotour destinations, are benefitting economically and ecologically from properly planned ecotourism.
66

Evaluation of Constructed Wetlands for the Waste Management of a Large Scale Swine Production Unit

Sutton, Robert 01 December 1996 (has links)
The effectiveness of using constructed wetlands to remove unwanted nutrients, increase dissolved oxygen while at the same time decreasing the biological oxygen demand, and to reduce the levels of the Fecal Coliform Bacteria from a swine operation was evaluated. The indicator of proper waste purification will be the result of testing for the following: ammonia nitrogen, nitrate nitrogen, total phosphorus, total suspended solids, dissolved solids, dissolved oxygen, biological oxygen demand, and Fecal Coliform Bacteria. The wetland was divided into nine connected cells that covered approximately 3.8 hectares. Material was loaded from an anaerobic holding lagoon on four separate occasions during the testing period. As the material passed through the wetland, the vegetation, water column, substrate, and microbial populations functioned as the purification factors in the wetlands. During the sampling period, water was collected from each cell and analyzed for results. The data indicated that the constructed wetlands were effective in the waste management at a large swine production unit. Ammonia nitrogen showed an acceptable decrease, allowing nitrogen to be freed or converted into nitrate nitrogen. Total phosphorus and dissolved solids showed an expected decrease. Total suspended solids showed an overall decrease from the upper cells to the lower cells; however, results fluctuated during the testing period. Dissolved oxygen and biological oxygen demand showed an almost perfect inverse relationship with dissolved oxygen increasing as biological oxygen demand decreased. The removal of Fecal Coliform Bacteria was the most impressive, with the majority of bacteria being removed in the upper cells.
67

Development of a systematic process to evaluate the effectiveness of environmental health and safety training at XYZ Medical Center

Nesbitt, Jeffrey C. January 2004 (has links) (PDF)
Thesis--PlanB (M.S.)--University of Wisconsin--Stout, 2004. / Includes bibliographical references.
68

Dietary and developmental exposure to the fungicide tolylfluanid disrupts global energy metabolism in mice

Regnier, Shane Michael 16 September 2015 (has links)
<p> The past several decades have witnessed a dramatic expansion in the rates of metabolic disease, most prominently the obesity and diabetes epidemics. While metabolic disease is undoubtedly driven by increased caloric intake and decreased physical activity, exposure to endocrine disrupting chemicals (EDCs) has been implicated as a causal factor in the development of metabolic disease. EDCs are exogenous compounds capable of modulating endogenous hormonal axes, with some compounds capable of interfering with metabolic pathways. Prior work identified the fungicide and booster biocide tolylfluanid (TF) as a potent EDC with the capacity to induce adipocyte differentiation and impair adipocyte insulin signaling through stimulation of the glucocorticoid receptor (GR). The present studies seek to expand upon these data by investigating the outcomes of dietary exposure to TF across the lifespan, with the hypothesis that TF disrupts energy metabolism through aberrant stimulation of the GR, and that disruptions in global metabolic homeostasis are driven by modulation of adipose physiology. When male mice were provided a diet supplemented with 100ppm TF, they exhibited several metabolic changes that mirror the metabolic syndrome, including augmented visceral adiposity, glucose intolerance, global and cellular insulin resistance, and disruptions in circadian rhythms. Importantly, gene set enrichment analysis identified an enrichment of GR-dependent genes in the adipose tissue of exposed mice. Next, investigating the interaction of TF with diet identified novel differences in the outcomes of exposure depending on the background macronutrient content of the diet. Finally, developmental exposure to TF during prenatal and early postnatal life was found to modulate insulin-glucose homeostasis in adult life, in a sex-dependent manner. Taken together, these findings identify TF as a novel metabolic disruptor <i> in vivo,</i> and support prior studies identifying TF as a potent environmental glucocorticoid.</p>
69

Estimating the Health Effects of Environmental Exposures: Statistical Methods for the Analysis of Spatio-temporal Data

Correia, Andrew William 09 October 2013 (has links)
In the field of environmental epidemiology, there is a great deal of care required in constructing models that accurately estimate the effects of environmental exposures on human health. This is because the nature of the data that is available to researchers to estimate these effects is almost always observational in nature, making it difficult to adequately control for all potential confounders - both measured and unmeasured. Here, we tackle three different problems in which the goal is to accurately estimate the effect of an environmental exposure on various health outcomes.
70

Epigenetics| The transgenerational transmission of ancestral trauma, experiences, and behaviors? as seen in systemic family constellations

Jelinek, Elizabeth Maureen 31 October 2015 (has links)
<p> A Systemic Family Constellation is a phenomenological systemic group process that promotes healing and transformation in individuals through the use of representatives who stand in for family members, so that entanglements with the ancestors can be revealed and brought to reconciliation. Family Constellations were created by German psychotherapist and former priest, Bert Hellinger, who spent 16 years as a missionary and educator with the Zulu peoples of South Africa. Hellinger suggests that individuals become entangled with the fate of the ancestors. This study proposes that epigenetics can explain the heritability of ancestral experiences. </p><p> This study explores the role of epigenetics in the transgenerational transmission of the effects of trauma, experiences, and behaviors of the ancestors as observed in Systemic Family Constellations. It employs a multiparadigmatic model of research and performs a systematic review of existing literature on epigenetics from the fields of biology, genetics, medicine and psychology, and demonstrates that some epigenetic changes can be inherited for as many as four generations&mdash;and possibly iv more, without any changes in the underlying DNA. A systematic review of existing literature has become a viable research method in the fields of medicine and the social sciences in recent years, and is used here to explore epigenetic changes in genomic expression that are transmitted transgenerationally. This study recommends that epigenetics be added as a scientific explanation to the existing metaphysical theories of how constellations work, that include: (a) the knowing field, (b) morphic fields and morphic resonance, and (c) indigenous ways of knowing. </p><p> Some of the examples of epigenetic inheritance presented in this study, include the epigenetic effects of major traumas, such as the bombing of the World Trade Center, the Holocaust, and the Dutch Hunger Winter, as well as the effects of mothering on the stress responses of their offspring, the effects of feast or famine in utero that can potentially result in schizophrenia, and the effects of child sex abuse on mental health in adulthood and on same sex orientation&mdash;as well as potential evolutionary changes.</p>

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