11 |
PCB-Contaminated Food in the Canadian Arctic: Interactions between Environmental Policy, Cultural Values, and the Healthcare SystemBrieger, Katharine K 01 January 2011 (has links)
Current Canadian policies do not adequately prevent water contamination or mitigate the effects of existing polychlorinated biphenyl pollution. There is conflict between the Canadian government and the Inuit people over how to approach the pollution problem, arising from a clash of cultural values and traditions. Legislation related to healthcare is an inherently sensitive issue and some measures that seem acceptable to westernized societies are not appropriate for the Inuit. The purpose of this thesis is to answer (a) why polychlorinated biphenyls (PCBs) are in the Arctic, (b) what the effects of PCBs are on the Arctic people, and (c) how healthcare policy can address the issue.
|
12 |
The Effects of Biodegradation on the Toxicity of Creosote in an Artificial SoilSams, J. P., Scheuerman, Phillip R. 01 January 1996 (has links)
No description available.
|
13 |
Frequency and Intensity Of Heat Waves In East Tennessee: Measurements Using Various Heat Wave DefinitionsAdesoba, Taiwo Peter, Li, Ying, Silver, Kenneth 04 April 2018 (has links)
Introduction: More frequent and intensive heat waves have been generally considered as a consequence of global climate change. In spite of the fact that there is a lack of generally accepted definition of heat waves in terms of intensity and duration, the adverse impacts of heat wave are undeniable. East Tennessee has experienced noticeably higher summer temperatures in the recent past, including possible deadly heat waves. This study aims at measuring the frequency and duration of heat waves in East Tennessee over the last ten years using various heat definitions extracted from epidemiological literature.
Methods: A literature search was conducted in PubMed using key words: Heat wave, mortality and morbidity. The search located 311 peer-reviewed articles that were screened and 108 were reviewed for heat wave definitions. The definitions used in the 108 articles were then summarized and seven most commonly used definitions were selected for this study. Daily temperature (mean, maximum and minimum) data from three weather stations namely Tri-City Airport, Kingsport and Elizabethton in East Tennessee were collected for the period from 2008 to 2017 to test the seven different definitions of heat waves. The World Meteorological Organization (WMO)’s definition “daily maximum temperature for more than five consecutive days exceeding the average maximum temperature (for the 30-year normals period) by at least 9º Fahrenheit (5º Celsius)” was also tested and compared with the seven definitions extracted from epidemiological literature.
Results: Using the WMO definition and temperature data from the Tri-City Airport Weather Station located in Bristol, TN, it was estimated that the total number of heat wave in the 10-year period was 58, which spanned a total of 1343 days, or 134.3 days per year on average. The results further indicate that the onset of heat wave days has been earlier within the past four years than the previous years with the earliest occurrence on February 24, 2017. Year 2016 is regarded as the hottest year in the period as virtually the whole of 2016 summer was a heat wave period. It is also worthy of note that the end-date of the heat wave episodes using the WMO definition is observed to have extended for the first time to the month of November as seen in 2016, which was not so for the other years. The heat wave episodes observed with the 97th percentile mean and 90th percentile minimum temperatures in Tri-City Airport Weather Station were lower than the WMO definition. Similar results were observed in Kingsport weather station. But in Elizabethton weather station, the 97th percentile mean and 90th percentile minimum temperatures produced higher episodes of heat waves but shorter days than the WMO definition.
Conclusion: Heat wave is deadly and evidences suggest that its manifestation may become severe as more damages are being done to the atmosphere through pollution and deforestation. A reversal of this trend through early warning systems and preparedness is very important and urgent. Further research will look into the mortality health outcome associated with heat waves in this region.
|
14 |
Determining How Temperature Affects the Survival of Salmonella and E. coli Species in Sinking Creek: A Meta-EvaluationLiner, Miranda 01 December 2019 (has links)
In recreational waters, pathogen pollution is a major concern for the USEPA. The USEPA is responsible for initiating the National 303(d) List of Impaired Surface Waters. Pathogen pollution from E. coli is a common reason why recreational waters are placed on the 303(d) list. E. coli O157 H:7 and other enteric pathogens can cause serious illness and even death. Sinking Creek is a part of the Watauga River watershed which runs through Carter and Washington county. Sinking Creek is currently listed on the 303(d) as impaired due to the presence of E. coli. Because of the known presence of E. coli, it is possible that other enteric pathogens may exist in the creek. The main objective of the study was to determine the presence of E. coli and Salmonella bacteria within Sinking Creek and was accomplished by using selective media to isolate the bacteria. The second goal of the study was to understand how various temperature treatments effect the growth of Salmonella and E. coli in Sinking Creek. Water samples from Sinking Creek were incubated at 4, 28, and 37°C. The third objective of the study was to determine how the survival of Salmonella and E. coli from Sinking Creek compared to samples taken from manure slurry via a meta-evaluation. It was predicted that Salmonella would not be present in water samples taken from Sinking Creek. It was further hypothesized that E. coli and any present Salmonella would have limited to no growth at 4°C and the most growth would occur at 37°C. A pilot study was conducted to determine the growth of microorganisms naturally present in Sinking Creek. The data from the pilot study was used to determine the creek’s ability to support a healthy microbiota. Samples for the main experiment were taken from September 2019 to November 2019. The main experiment found that Salmonella was present in Sinking Creek at lower amounts than E. coli. Both E. coli and Salmonella grew significantly at 4°C. On average, the least amount of growth for Salmonella and E. coli was at 37°C. Most growth on R2A peaked at 5 days of incubation. Water incubated at 37°C showed the highest growth peaks at 5 days for all three selective plates. For all three selective plates, water incubated at 4°C peaked in growth between days 5 and 7. The results of the main experiment could have been affected by factors such as contamination. Another limitation of the study was that enumeration of the colony forming units became less accurate after larger colonies had formed. Replicating the main experiment over a longer period could indicate more representative growth curves. The meta-evaluation concluded there was no difference in decay rate between samples taken from water or manure. The results of the meta-evaluation disproved the hypothesis that manure would have lower decay rates than samples taken from water. A larger sample size is recommended to yield more representative results for the meta-evolution. Further replications of the main experiment are recommended along with studies sampling the presence of Salmonella and E. coli at various distances from the below wetlands site.
|
15 |
Risk Factors of Diarrheal Disease Among Children in the East African Countries of Burundi, Rwanda and TanzaniaO'Connell, Bethesda J., Quinn, Megan, Scheuerman, Phillip R. 01 January 2017 (has links) (PDF)
Diarrheal diseases are a leading cause of childhood morbidity and mortality globally and in East Africa. Determining diarrheal disease risk factors and their strength of association to diarrheal disease in this region is necessary to identify and prioritize future research questions and interventions. Demographic and Health Surveys (DHS) Program Data on child health in Burundi, Rwanda, and Tanzania from 2010 were used and simple and multiple logistic regressions were completed to determine factors that predicted diarrheal disease. Diarrhea that occurred in the two weeks prior to data collection was reported for 24.80% of Burundian, 13.1% of Rwandan, and 13.91% of Tanzanian children under five. In Burundian children, increased risk of diarrhea was associated with unimproved sanitation, young mothers, and the mother’s education level (secondary school or less). In Rwandan children, increased risk of diarrhea was associated with more than 30-minute travel time to water source, rainy season, young mothers, mother’s lack of education, and low wealth index. In Tanzanian children, increased risk of diarrhea was associated with rainy season and young mothers. The impact of improved water source and sanitation facility on diarrheal disease is not consistent across the literature or results of this study. Future research should include information on hygiene practices, type of water storage container and types of household water treatment. Further, pathogen specific research, such as molecular fingerprinting, would assist to link the source to the disease. These additions would provide a more comprehensive understanding of risk factors for and sources of diarrheal disease globally and in East Africa.
|
16 |
Comparing Heatwave Related Mortality Data from Distressed Counties to Affluent Counties in Central and Southern Central AppalachiaPardue, Miranda Taylor 01 May 2020 (has links)
The Appalachian Mountains are home to some of the most culturally rich places in the United States, but also some of the most impoverished communities as well. Several recent events support climate change across the globe. It is expected that Appalachian communities may suffer more dire consequences, as many communities lack strategies to help relieve some of the worst effects of climate change. Heatwaves are predicted to increase in duration and frequency over time, and communities that are not well prepared for the damaging effects of heatwaves can suffer unduly. This study aims to quantify the likelihood that people living in economically distressed counties in the Central and Southern Central regions of Appalachia will face heatwave related mortality more intensely than those who live in more affluent counties in the same regions. Twelve counties from each socioeconomic group have been selected based on the county economic status to analyze climate and mortality data over thirty-eight years starting in 1981 and ending in 2018. Data was collected during the warm season for each county, May 1st to September 30th, and compared to the mortality data from the same county during the same warm season. This study used all-cause mortality numbers from each of the twenty-four counties for the mortality data. The relative risk for each county in both the distressed and affluent categories was calculated. The average relative risk for each socioeconomic status were then compared. The results of this study did not show statistical significance in the likelihood that being in a socioeconomically distressed county increases one's chances of succumbing to heatwave related mortality in the Central and Southern Central regions of Appalachia. More research with larger sample sizes and more attention paid to the factors driving socioeconomic status is needed to better assess the relationship of heatwave mortality to socioeconomic status.
|
17 |
The Impact of Pesticides on the White-Faced IbisCapen, David E. 01 May 1977 (has links)
The white-faced ibis (Plegadis chihi) which nested in northern Utah was assessed as a species with a relatively low reproductive potential. Ibises normally laid either three or four eggs in a clutch and did not renest persistently, nor with good success, if initial nesting attempts failed. Evidence indicated that the birds did not breed until at least 2 years old. Competition for food, exposure to severe weather, and predation were conspicuous sources of nestling mortality. White-faced ibises usually fed in irrigated agricultural areas, where they came into direct contact with insecticides, such as DDT which was used routinely in northern Utah until 1971. The most frequent food items of the ibises were insect larvae and earthworms, hence the birds were subject to food-chain concentrations of pesticide residues.
White-faced ibises commonly laid eggs with cracked or broken shells from 1968 through 1971, but the incidence of aberrant eggs decreased after 1971. By 1974, no significant difference was found between the current mean eggshell thickness and the thickness of eggshells collected before 1940 and preserved in museums. Also, in 1974, less than 1 percent of nests surveyed contained cracked eggs. White-faced ibises in Utah again laid thin-shelled eggs in 1975 and 1976, Cracked eggs were found in about 30 percent of nests examined during both of these years, and the means of eggshell thickness were significantly less than in 1974. A high incidence of cracked eggs was associated with less than 10 percent thinning of eggshells.
Eggshell thickness of white-faced ibis eggs collected in 1975 was significantly related, linearly and negatively, to the logarithms of DDE residues of the eggs. The comparison of this relationship to those of other species indicated that the white-faced ibis is especially sensitive to eggshell thinning.
DDE residues were found in samples of blood serum, breast muscle. and subcutaneous fat of white-faced ibises collected in 1974 and 1975. The logarithm of DOE in blood serum was positively correlated with 1n DDE in fat and with ln DDE in muscle. DDE levels in blood serum were related to lipid mobilization and varied by season and between sexes.
|
18 |
The Characterization of Chitin Microparticle Preparations: Degree of Acetylation and its Effect on Immunologic ResponseZimmerman, Julianne R 29 August 2014 (has links)
Studies examining the immune response upon exposure to chitin microparticles in living models have reached drastically differing conclusions, and the reason remains unclear. One notable issue between the experiments is that they have not characterized their chitin preparations for degree of acetylation. They all use different chitin processing methods prior to administration, which could potentially be the source of the variance between studies. Chitin and chitosan preparations specified in the literature and several novel preparations were analyzed for degree acetylation (DA) using High Performance Anion-Exchange Chromatography with Pulsed Amperometric Detection (HPAEC-PAD). It was found that autoclaving and sonication processing steps do not have a significant influence on degree of acetylation. Chitin and chitosan preparations were used to create a dose-response curve of DA compared to cytokine elicitation from THP-1 monocytes, and it was found that the initial response was dominated by TNF (similar to previous studies), though after 12 hours showed a tip toward the start of an IL-1β-dominated Th17 effector response. This study also confirmed that immunostimulatory effects can occur from chitin and chitosan particles at orparticles, which would have long residence times in air, might be implicated in initiating allergic or asthmatic processes.
|
19 |
Exploring the built environment and physical activity in rural Ontario health unitsCoghill, Cara-Lee M. 04 1900 (has links)
<p>The purpose of this thesis was to explore how health units servicing large rural populations in Ontario are integrating the built environment into public health interventions related to physical activity for the purpose of fostering healthy and sustainable communities. Additionally, this research sought to identify barriers and/or enabling structures that rural health units face in addressing the built environment within physical activity programming.</p> <p>This exploratory research study employed a descriptive qualitative approach. Semi-structured interviews were conducted with a purposeful sample of public health practitioners and managers identified by participating health units (n=12) as those most knowledgeable about program planning, implementation, and policy development in relation to physical activity and the built environment. Key themes were identified using qualitative content analysis and an inductive approach.</p> <p>The types of interventions were: engagement with policy work at a county or municipal level; building and working with community partners; gathering and providing evidence; hosting knowledge sharing opportunities; program development and implementation; social marketing, information sharing and awareness raising; and resource development and dissemination. Barriers and enabling processes and structures were identified at an organizational, community, and systemic level. Specific rural contextual enablers and barriers were also identified.</p> <p>This was the first study to the researchers’ knowledge that has examined current practices of Ontario’s rural health units related to built environment initiatives. In-depth perspectives elicited from public health practitioners and managers address gaps in the literature and contributes to new knowledge regarding built environment interventions to enhance physical activity in rural settings.</p> / Master of Science (MSc)
|
20 |
Concentration Levels of PM2.S and PM 10 Paper Dust in a Book Production FacilityCvengros, Blake J 01 April 2017 (has links)
Concentration levels of PM2.5 and PM10 paper dust were measured in a book production facility using a quantitative single subject study. Dust concentration data was collected in three processes of a book manufacturing facility; paper recycling, the digital pressroom and the digital bindery. Data was collected using the DustTrak DRX 8533 Aerosol Monitor, focusing on particulate sizes of PM2.5 and PM10. The data was used to determine if paper dust in the book production industry reached concentration levels that could have negative respiratory health effects on surrounding employees and to determine which process within the studied facility had the highest concentrations of paper dust. The study revealed that the paper recycling warehouse had the highest concentrations of paper dust. It was also determined that the paper recycling warehouse could cause negative respiratory health effects on surrounding employees. Further research is needed to determine the extent of those effects and potential remediation.
|
Page generated in 0.0994 seconds