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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.
191

Perspectives on Policy Framework for Trans-Boundary Water Quality Management in China

Zhang, Wei, Zhen, Gengchong, Tong, Yindong, Yang, Lei, Zhu, Yan, Liu, Guohua, Wang, Xuejun, Li, Ying 02 April 2016 (has links)
In river basins that cross jurisdictional boundaries, water quality degradation has become a crucial problem and results in intensive competition among water users, especially in developing countries. Under this situation, implementing water quality management and control across jurisdictional boundaries can strengthen watershed pollution controls, and prevent pollution from being passed on and promote active pollution control within the related jurisdictional regions. This study examined the limitations of the current trans-boundary water quality management system in China and reviewed the planning and implementation of two pilot integrated trans-boundary water management systems established in the Jiangsu and Zhejiang provinces. Based on our findings, we proposed a new policy framework for trans-boundary water quality management. As a first step toward integrated watershed management in China, this policy framework can help assess the actual water pollution status of various regions and serve as a basis for an integrated watershed management system. The framework can be easily applied in other countries with trans-boundary water pollution issues, particularly in the context of developing countries.
192

The Influence of Air Quality Model Resolution on Health Impact Assessment for Fine Particulate Matter and Its Components

Li, Ying, Henze, Daven, Jack, Darby, Kinney, Patrick L. 01 February 2016 (has links)
Health impact assessments for fine particulate matter (PM2.5) often rely on simulated concentrations generated from air quality models. However, at the global level, these models often run at coarse resolutions, resulting in underestimates of peak concentrations in populated areas. This study aims to quantitatively examine the influence of model resolution on the estimates of mortality attributable to PM2.5 and its species in the USA. We use GEOS-Chem, a global 3-D model of atmospheric composition, to simulate the 2008 annual average concentrations of PM2.5 and its six species over North America. The model was run at a fine resolution of 0.5 × 0.66° and a coarse resolution of 2 × 2.5°, and mortality was calculated using output at the two resolutions. Using the fine-modeled concentrations, we estimate that 142,000 PM2.5-related deaths occurred in the USA in 2008, and the coarse resolution produces a national mortality estimate that is 8 % lower than the fine-model estimate. Our spatial analysis of mortality shows that coarse resolutions tend to substantially underestimate mortality in large urban centers. We also re-grid the fine-modeled concentrations to several coarser resolutions and repeat mortality calculation at these resolutions. We found that model resolution tends to have the greatest influence on mortality estimates associated with primary species and the least impact on dust-related mortality. Our findings provide evidence of possible biases in quantitative PM2.5 health impact assessments in applications of global atmospheric models at coarse spatial resolutions.
193

Agricultural Water Consumption Decreasing Nutrient Burden at Bohai Sea, China

Tong, Yindong, Wang, Xuejun, Zhen, Gengchong, Li, Ying, Zhang, Wei, He, Wei 05 February 2016 (has links)
In this study, we discussed the impacts of human water consumption to the nutrient burden in a river estuary, and used Huanghe River as a case study. The agricultural water consumption from the Huanghe River has significantly decreased the natural water flows, and the amount of water consumption could be almost twice as high as the water entering into the estuary. According to our calculation, agricultural water usage decreased TN outflows by 6.5 x 104 Mg/year and TP outflows by 2.0 x 103 Mg/year. These account for 74% and 77% of the total output loads. It has been widely reported that the majority of the rivers in northern China were severely polluted by nutrients. Its implication on the budget of nutrient in the estuary ecosystem is not well characterized. Our study showed that the discharge of nutrients in the coast waters from polluted rivers was over concerned. Nutrients in the polluted rivers were transported back to the terrestrial systems when water was drawn for human water consumption. The magnitudes of changes in riverine nutrient discharges even exceed the water-sediment regulation trails in the Huanghe River. It has non-negligible impact on estimating the nutrient burden in costal water ecosystem.
194

Assessing Public Health Burden Associated with Exposure to Ambient Black Carbon in the United States

Li, Ying, Henze, Daven K., Jack, Darby, Henderson, Barron H., Kinney, Patrick L. 01 January 2016 (has links)
Black carbon (BC) is a significant component of fine particulate matter (PM2.5) air pollution, which has been linked to a series of adverse health effects, in particular premature mortality. Recent scientific research indicates that BC also plays an important role in climate change. Therefore, controlling black carbon emissions provides an opportunity for a double dividend. This study quantifies the national burden of mortality and morbidity attributable to exposure to ambient BC in the United States (US). We use GEOS–Chem, a global 3-D model of atmospheric composition to estimate the 2010 annual average BC levels at 0.5 x 0.667° resolution, and then re-grid to 12-km grid resolution across the continental US. Using PM2.5 mortality risk coefficient drawn from the American Cancer Society cohort study, the numbers of deaths due to BC exposure were estimated for each 12-km grid, and then aggregated to the county, state and national level. Given evidence that BC particles may pose a greater risk on human health than other components of PM2.5, we also conducted sensitivity analysis using BC-specific risk coefficients drawn from recent literature. We estimated approximately 14,000 deaths to result from the 2010 BC levels, and hundreds of thousands of illness cases, ranging from hospitalizations and emergency department visits to minor respiratory symptoms. Sensitivity analysis indicates that the total BC-related mortality could be even significantly larger than the above mortality estimate. Our findings indicate that controlling BC emissions would have substantial benefits for public health in the US.
195

Oh what a tangled web ... : Building capacity for environmental health action in Australia

Nicholson, Rosemary J., Public Health & Community Medicine, Faculty of Medicine, UNSW January 2003 (has links)
In the early years of the 21st century environmental health has to contend not only with the more 'traditional' and essentially localised environmental risks to human health. We now face the additional challenges posed by a range of 'modern' environmental health issues. These are characteristically more complex, more ubiquitous, and much less clearly defined than any we have previously encountered. They have been brought about through rapid industrial expansion, technological advances that have transformed our social structures and the emergence of a global economy that is now forging ahead in the face of ever-increasing socio-economic inequity. These are problems that are not amenable to traditional environmental health solutions. They call instead for new, innovative and integrative strategies based on cooperative and collaborative working partnerships. This thesis explores the question of what needs to be done to build capacity for such partnerships among environmental health stakeholders in Australia. The current situation is clarified through a critical review of the author?s professional career, the historical development of environmental health practice, the different knowledge constructs of four distinguishable stakeholder groups and the objectives and guiding principles of Australia's National Environmental Health Strategy. A case study of a federally funded collaborative environmental health project serves to highlight some of the inherent challenges of intersectoral partnership and community participation. The metaphor of the spider's web illustrates the imperative of such partnerships among stakeholder groups and across all geographical scales from the local to the global. Finally, the barriers to be overcome in building environmental health capacity are analysed through a force field analysis. The study concludes with an analysis of the constituents of action necessary to develop the partnering capabilities of the various stakeholders, to build supportive community and organisational infrastructures and to demonstrate the political will of government to support change.
196

An integrative approach to characterizing the estrogenicity gradient of a portion of the South Platte River

Bourdon, Lisa Marie 08 June 2016 (has links)
<p>Endocrine disrupting compounds (EDCs) from agricultural, industrial, and municipal sources can be found in many surface waters with potential adverse implications for human and ecosystem health. The South Platte River represents a significant source of water for the Denver Metro Area, yet little data exists concerning EDCs. The aim of this study is to evaluate the occurrence and effects of EDCs downstream from two major wastewater treatment plants (WWTPs). This study characterizes the estrogenicity gradient of the South Platte River in the Denver Metro area by combining data from qPCR analysis for liver vitellogenin (<i>vtg</i>) mRNA with liver NMR metabolomics after a 5 day in situ caged exposure of fathead minnows. Concurrent water samples collected from the start and end times of the exposures were used to determine the occurrence and concentration of wastewater contaminants. Results found 68 of 122 chemicals downstream of WWTP 1 and 73 downstream of WWTP 2, including known EDCs (e.g. nonylphenol and octylphenol). A steroidal estrogen, estrone, was only found downstream of WWTP 2. Consistent with the highest measured concentrations of wastewater estrogens, the highest levels of <i>vtg</i> mRNA were measured downstream of WWTP 2. Metabolomics data coincided with <i>vtg </i> data and showed little variation except downstream of WWTP 2, where male polar metabolomes showed increased levels of alanine and glutamate, which are utilized in VTG synthesis. PCA of male polar metabolomes showed significant separation of WWTP 2 from WWTP 1 and the reference site, further supported by PLS-DA scores plot. Female polar metabolomes showed significant separation between WWTP 1 and WWTP 2 using PLS-DA scores plot. This study demonstrates that qPCR and metabolomics data can be reliably and concurrently used to illuminate impacts from chemical exposures, although further research will better elucidate target genes and metabolites of interest. </p>
197

Comparison of Urinary PAHs among Firefighters and Asphalt Pavers

Aquino, Theodore 20 May 2016 (has links)
<p>Firefighters and asphalt pavers are exposed to polycyclic aromatic hydrocarbons (PAHs) during various work activities. The purpose of this study was to evaluate urinary PAH levels and compare these bio-monitoring levels among firefighters, asphalt pavers, and non-occupationally exposed individuals. The National Institute of Standards and Technology (NIST) urinary PAH levels were used for non-occupationally exposed controls. When compared to the NIST standard for smokers and non-smokers, firefighters demonstrated statistically significant differences in urinary concentration differences for the following metabolites: 2-OH-fluorene, 3-OH-fluorene and 1-OH-pyrene, which were lower in firefighters than the NIST mean for smokers. 1-OHphenanthrene, 2-OH-phenanthrene and 3-OH-phenanthrene were higher among world trade center exposed firefighters than the NIST mean for smokers. When firefighters were compared to the NIST non-smoker standard, firefighters demonstrated elevated levels in all tested PAH biomarkers due to a mixture of smokers and non-smokers in the firefighter cohort. </p><p> Asphalt workers had statistically significant higher urinary concentration elevations in 2OH-fluorene, 1-OH-phenanthrene and 3-OH-phenanthrene as compared to the NIST smoker mean. When asphalt pavers were compared to the NIST non-smoker mean, asphalt pavers had statistically significant increases in all tested PAH biomarkers, with the exception of 2-OHphenanthrene. While firefighters did not demonstrate a substantial change in urinary PAH metabolite levels compared to control populations of smokers and non-smokers, asphalt pavers experienced concentrations that were in some cases increased by orders of magnitude compare to NIST controls. Future research may be needed to evaluate any potential health risk posted to occupational exposed asphalt pavers. </p>
198

Investigating the Potential of Land Use Modifications to Mitigate the Respiratory Health Impacts of NO2| A Case Study in the Portland-Vancouver Metropolitan Area

Rao, Meenakshi 30 June 2016 (has links)
<p>The health impacts of urban air pollution are a growing concern in our rapidly urbanizing world. Urban air pollutants show high intra-urban spatial variability linked to urban land use and land cover (LULC). This correlation of air pollutants with LULC is widely recognized; LULC data is an integral input into a wide range of models, especially land use regression models developed by epidemiologists to study the impact of air pollution on human health. Given the demonstrated links between LULC and urban air pollution, and between urban air pollution and health, an interesting question arises: what is the potential of LULC modifications to mitigate the health impacts of urban air pollution? </p><p> In this dissertation we assess the potential of LULC modifications to mitigate the health impacts of NO<sub>2</sub>, a respiratory irritant and strong marker for combustion-related air pollution, in the Portland-Vancouver metropolitan area in northwestern USA. We begin by measuring summer and winter NO<sub>2</sub> in the area using a spatially dense network of passive NO<sub> 2</sub> samplers. We next develop an annual average model for NO<sub>2</sub> based on the observational data, using random forest&mdash;for the first time in the realm of urban air pollution&mdash;to disentangle the effects of highly correlated LULC variables on ambient NO<sub>2</sub> concentrations. We apply this random forest (LURF) model to a 200m spatial grid covering the study area, and use this 200m LURF model to quantify the effect of different urban land use categories on ambient concentrations of NO<sub>2</sub>. Using the changes in ambient NO<sub>2</sub> concentrations resulting from land use modifications as input to BenMAP (a health benefits assessment tool form the US EPA), we assess the NO<sub>2</sub>-related health impact associated with each land use category and its modifications. We demonstrate how the LURF model can be used to assess the respiratory health benefits of competing land use modifications, including city-wide and local-scale mitigation strategies based on modifying tree canopy and vehicle miles traveled (VMT). </p><p> Planting trees is a common land cover modification strategy undertaken by cities to reduce air pollution. Statistical models such as LUR and LURF demonstrate a correlation between tree cover and reduced air pollution, but they cannot demonstrate causation. Hence, we run the atmospheric chemistry and transport model CMAQ to examine to what extent the dry deposition mechanism can explain the reduction of NO<sub>2</sub> which statistical models associate with tree canopy. </p><p> Results from our research indicate that even though the Portland-Vancouver area is in compliance with the US EPA NO<sub>2</sub> standards, ambient concentrations of NO<sub>2</sub> still create an annual health burden of at least $40 million USD. Our model suggests that NO<sub>2</sub> associated with high intensity development and VMT may be creating an annual health burden of $7 million and $3.3 million USD respectively. Existing tree canopy, on the other hand, is associated with an annual health benefit of $1.4 million USD. LULC modifications can mitigate some fraction of this health burden. A 2% increase in tree canopy across the study area may reduce incidence rates of asthma exacerbation by as much as 7%. We also find that increasing tree canopy is a more effective strategy than reducing VMT in terms of mitigating the health burden of NO<sub> 2</sub>. </p><p> CMAQ indicates that the amount of NO<sub>2</sub> removed by dry deposition is an order of magnitude smaller than that predicted by our statistical model. About one-third of the difference can be explained by the lower NO<sub>2</sub> values predicted by CMAQ, and one-third may be attributable to parameterization of stomatal uptake. </p>
199

The effect of air pollutants on functional and biochemical changes in bronchial epithelial cells from atopic patients with mild asthma and non-atopic non-asthmatic volunteers

Bayram, Hasan January 1998 (has links)
No description available.
200

Personal exposure to 50 Hz electromagnetic fields from sources in the home and external environment

Grainger, Peter January 2000 (has links)
No description available.

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