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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.

The Impact of a Workplace Environmental Change on Work- Related Outcomes: Productivity, Presenteeism and Cognition

January 2014 (has links)
abstract: The purpose of this study was to examine whether a workplace environmental intervention would improve work-related outcomes including productivity, presenteeism and cognition. The secondary aim was to investigate whether work-related outcomes are correlated to observed changes in sitting time, physical activity, and sleep. The study was introduced as part of a naturalistic environmental change in which university staff and faculty were relocated into a new building (n=23). The comparison group consisted of university staff within the same college with no imminent plans to re-locate during the intervention period; there were no environmental changes to this workplace (n =10). Participants wore two behavioral monitoring devices, activPAL and GeneActiv, for 7 consecutive days at two time points (immediately prior and 16 weeks following the office relocation). Measures of productivity and presenteeism were obtained via four validated questionnaires and participants underwent cognitive performance testing. Baseline adjusted analysis of covariance statistical analyses were used to examine differences between groups in work-related outcomes. A residual analysis in regression was conducted to determine the differences between observed changes in sitting time, physical activity and sleep, and work-related outcomes. The results showed that a reduction in work hour sitting time was not detrimental to work related outcomes. Decreased sitting was observed to potentially improve presenteeism and absenteeism. Additionally, physical activity was shown to modestly improve productivity, presenteeism and absenteeism. Poor sleep patterns were associated with work impairment and increased absenteeism. / Dissertation/Thesis / M.S. Exercise and Wellness 2014

Determinants of occupational allergic respiratory disease and asthma in spice mill workers

Van der Walt, Anita January 2010 (has links)
Includes abstract. / Includes bibliographical references (leaves 94-100). / The aim of this study was to determine the prevalence of occupational allergy and asthma associated with airborne spice and to determine the host and environmental risk factors associated with allergic respiratory disease among spice mill workers. A cross-sectional epidemiological study of 150 currently employed workers in a spice mill was conducted. Environmental exposure assessment entailed the collection of 62 full-shift airborne personal samples on randomly selected individuals employed in various departments of the spice mill using the NIOSH occupational exposure sampling strategy manual. The samples were analysed for inhalable particulate mass, specific spice dust allergens (garlic) and endotoxin using ELISA inhibition (antibodies from sensitised subjects) and chromogenic LAL assays.

Obstructive Lung Disease among tobacco farmers in Malawi

Moyo, Yotam Mgonjetsi 16 February 2021 (has links)
Introduction and aim Tobacco farmers are exposed to toxic workplace hazards such as nicotine and pesticides in addition to known agriculture related hazards like dust, and ergonomic factors. Nicotine and pesticide exposure have been linked to the development of chronic respiratory diseases. This study was aimed at determining the prevalence of obstructive lung disease among tobacco farmers in Malawi and its association to nicotine and pesticide exposure. Methods A cross-sectional study was conducted comprising of 279 current workers across four flue-cured tobacco farms in rural Zomba district of Malawi during a tobacco growing season. The assessment involved the use of a modified ECRHS questionnaire and questions on pesticides and nicotine exposure. Voluntary HIV testing was offered to individuals who did not know their HIV status. Health outcomes assessment involved the use of both symptom and spirometry-based diagnoses of obstructive lung disease. The data was analyzed using STATA 14 computer software and included bivariate and multivariate logistic regression analysis. Results The study had predominantly male participants (68%) with a total mean age of 37.7 years, majority (73%) of whom had attained primary education or higher, with 20% being current smokers. Participants had a mean employment duration of 7.3 years and 62% indicated that they worked mainly with tobacco while 57% were involved in pesticides application. HIV prevalence was 16%. The prevalence of current asthma (ECRHS) was 20% whilst for asthma score≥2 it was 23%. The prevalence of chronic bronchitis, work related ocular nasal symptoms and work- related chest symptoms were 17%, 20% and 29%, respectively. Airflow Limitation measured as FEV1 < LLN was 14% (NHANES and sample reference). The prevalence of moderate to severe obstruction was 4%. The prevalence of green tobacco sickness (a proxy for nicotine exposure) in the past year was 26% with an average of 3 episodes within that period. Most workers were exposed to pesticides with 72% reporting exposure during spraying of pesticides while 83% reported re-entry into fields soon after spraying. The main pesticide in use was organophosphates (18%). The majority (51%) of participants reported use of organophosphate pesticides at home. In multivariate analysis nicotine exposure and associated tasks were significantly associated with all respiratory outcomes (OR range 1.78-7.26). Pesticide application was positively associated with all the symptom-based respiratory outcomes (OR 1.96- 2.62) except for work related chest symptoms. Exposure during spraying was significantly associated with asthma score≥2 (OR 2.09, CI 1.01-4.31), current asthma (OR 2.57, CI 1.22-5.40), and work related ocular nasal symptoms (OR 2.43, CI 1.17- 5.04) while pesticide drift was associated with current asthma (OR 2.62, CI 1.00-6.86) and work related ocular nasal symptoms (OR 3.00, CI 1.18-7.62). In spirometry-based outcomes duration of pesticide exposure was significantly associated with FEV1/FVC< LLN (OR 5.11, CI 1.57-16.66), FEV1/FVC< 70% (OR 4.58, CI 1.17-17.98) and moderate to severe obstruction (OR 13.25, CI 1.69-103.93). Nicotine exposure was not significantly associated with spirometry-based outcomes. Conclusion In conclusion, this study showed that tobacco farmers in Malawi have a higher prevalence of asthma and chronic bronchitis compared to the general population or tobacco farmers in other settings. Additionally, exposure to nicotine and pesticides is strongly associated with the prevalence of obstructive lung diseases among these farmers.

A Proposed industrial hygiene program based on an integrated service with the local health departments a report submitted in partial fulfillment ... Master of Public Health ... /

Garber, Louis F. January 1947 (has links)
Thesis equivalent (M.P.H.)--University of Michigan, 1947.

A Proposed industrial hygiene program based on an integrated service with the local health departments a report submitted in partial fulfillment ... Master of Public Health ... /

Garber, Louis F. January 1947 (has links)
Thesis equivalent (M.P.H.)--University of Michigan, 1947.


Gao, Fei 06 February 2006 (has links)
The adverse health consequences of air pollution are well recognized and range from minor upper respiratory system irritation to severe chronic lung disease. The identity and mechanisms of these pollutants, as well as how toxicity is influenced by additional risk factors are unclear. This study elucidates the relationship between air pollution and microbial agents and explores the mechanisms by which the two stimuli interact to cause adverse health effects with important public health relevance. Mycoplasma fermentans is a species of atypical bacteria with immune-regulatory properties and potential to establish chronic latent infections. Particulate matter (PM) is a complex and diverse component of air pollution associated with adverse health effects. The hypothesis of this study is that M. fermentans infection modulates the cellular responses induced by exposure to residual oil fly ash (ROFA), a type of PM particularly rich in metals. Using human lung fibroblasts (HLF) as an in vitro model I measured the release of the immune-modulating cytokine interleukin-6 (IL-6) as a biomarker of stress-induced cell activation after exposure to various chemical and microbial challenges alone or together. The synergistic interaction between live M. fermentans and ROFA to stimulate IL-6 release and gene expression in HLF was demonstrated. This effect was specific for PM that contains high amounts of water-soluble metal and was recapitulated when NiSO4 was substituted for ROFA. The potentiating effect of live infection was mimicked by exposure to M. fermentans-derived macrophage-activating lipopeptide-2 (MALP-2), a Toll-like receptor-2 agonist. Experiments with consecutive singular exposures to MALP-2 and NiSO4 revealed that pre-treatment of cells with NiSO4 facilitated MALP-2-induced IL-6 production, while pre-exposure to MALP-2 failed to influence the response to Ni. Facilitation of MALP-2 response by NiSO4 depended, in part, upon Ni-induced activation of the ERK1/2 MAP kinase. These interactive effects were studied at the level of gene transcription using a series of IL-6 promoter-luciferase reporter constructs and mutants.

Adult Asthma: The Use of Novel Public Health Methods to Investigate the Prevalence of Environmental Risk Factors

Ramos, Rosemarie Govea 03 February 2006 (has links)
Although the incidence of new cases of asthma has decreased in recent years, the prevalence of asthma morbidity continues to be a significant clinical and public health issue. The measures of morbidity include the need for urgent medical care and high-dose asthma medications due to uncontrolled asthma symptoms. However, the risk factors for uncontrolled asthma symptoms are poorly defined, especially for the adult asthmatic. Much interest in the host-environment interaction has evolved in response to the greater morbidity observed in adult asthmatics. Thus, the need to identify risk factors is greater than ever. An underlying problem is that surveillance for asthma does not exist at the local or state level. Here we address the concept of environmental health surveillance by demonstrating the utility of local asthma hospitalization data to estimate the burden of asthma morbidity in hopes of identifying environmental risk factors. We examine this burden within 2 geographic settings: 1. a selected urban-rural setting in Pennsylvania and 2. within the 89 zip codes in Allegheny County, Pennsylvania. We also demonstrate that such hospitalization records are a rich source for data needed to generate hypotheses with respect to the prevalence of environmental risk factors and chronic disease morbidity. Lastly, we demonstrate the use of a non-invasive biomarker (i.e. antibodies specific for atypical respiratory pathogens) to assess the risk of exposure to a biological environmental agent to adult asthma morbidity. Given the poor understanding of risk factors for adult asthma prevalence and morbidity, this research is both relevant and important in addressing environmental public health disparities.


Liu, Yan 27 September 2007 (has links)
This study recruited local anglers to catch catfish from 3 locations within the Pittsburgh Pool and an upstream location on Allegheny River at Kittanning Dam to compare the As, Hg and Se levels in catfish fillet. The objectives were: to find if there exist locational differences of As, Hg and Se levels in catfish flesh; use catfish as sentinels to identify the sources of pollution; determine if any catfish had mercury levels above the EPA criterion; and assess the consumption risk for semi-subsistence anglers and their families. Local store-bought catfish are also compared with river-caught samples. Fish tissue was prepared following EPA method 3052. As and Se were analyzed by collision cell ICP-MS with calibration by standard addition methods. Mercury was analyzed by isotope dilution cold vapor ICP-MS. Data were log-transformed and analyzed by ANOVA with Tukey Post-Hoc Comparisons. There were no significant differences in As, Hg and Se concentrations among the Pittsburgh Pool catch, so we combined these data. Significantly higher levels of Hg and Se were found in Kittanning-caught fish even given significantly smaller fish sizes compared to those caught in the Pittsburgh Pool. The store-bought fish were significantly lower in As, Hg and Se than those caught in the Pittsburgh Pool. In addition, 23% of samples caught in Kittanning had higher mercury levels than the EPA criterion. Hg and Se levels in samples are significantly positively correlated. Using upper 95% CI of mean mercury level in Kittanning-caught catfish flesh, the maximum monthly allowable fish consumption limit for adult anglers is 4 meals, for children below 16 years old is 2 meals, and for women of childbearing age is 3 meals. Conclusions: The Hg and Se levels in catfish in Pittsburgh Rivers vary significantly by location. Fishers are exposed to higher Hg and Se levels when they eat the fish caught near Kittanning and Pittsburgh pool than bought from the fish market. Public health implications: River areas upstream from Pittsburgh may have higher mercury levels than those nearer Pittsburgh because of deposition of emissions from coal-fired power plants. Location specific fish consumption advisories are needed for local fishers.

Nitric Oxide-Mediated Signaling in Pulmonary Endothelial Cells

Stitt-Fischer, Molly Sue 26 June 2008 (has links)
S-nitrosothiol modifications of proteins are emerging as an important nitric oxide-mediated signaling pathway. Our laboratory has focused on S-nitrosation of the metal binding protein metallothionein and the resulting effects on zinc homeostasis, gene and protein expression and nitric oxide (NO) mediated signaling in the pulmonary endothelium. Statement of public health significance: The pulmonary endothelium is responsible for filtering the blood before it enters systemic circulation, and as such it is extremely vulnerable to injury by inhaled toxicants in the environment as well as those that circulate in the bloodstream. As the endothelium constitutively produces NO, we are interested in studying NO-mediated signaling in order to lay a foundation that will allow us to better understand diseases such as asthma, pulmonary hypertension and sepsis in which dysregulation of NO-mediated signaling is thought to be a contributing factor to the disease pathology. To this end we have used both recombinant DNA and biochemical techniques to examine the relationship between metallothionein, zinc homeostasis and the metal responsive transcription factor MTF-1. We demonstrated that exposure to NO results in zinc release from metallothionein, which in turn activates MTF-1, resulting in nuclear translocation of the protein and NO-dependent increases in metallothionein protein expression. We hypothesized that S-nitrosation of the sulphydryl groups in metallothionein were the cause of NO-mediated zinc release and downstream protein expression effects. We used a fluorescent modification of the biotin switch assay in combination with two-dimensional electrophoresis and mass spectroscopy to extend our study of NO-mediated signaling through S-nitrosation of protein thiols to identify S-nitrosated metallothionein in endothelial cells exposed to NO donor, and used the technique in further studies to illuminate the proteome of pulmonary endothelial cells. We were able to identify several potential targets of S-nitrosation in endothelial cells including cytoskeletal, cytoprotective, glycolytic and chaperone proteins. The proteomic assay that we developed is a useful screening tool, and may lead to new insights in post-translational S-nitrosothiol modifications of endothelial proteins, and eventually to new perspectives regarding diseases exacerbated by dysregulation of this NO-mediated signaling pathway.


Rucekova, Alica 26 September 2008 (has links)
Background: Breast cancer is a worldwide public health concern. Breast cancer now ranks first not only in the industrialized world but also in the developing world. In the United States, breast cancer is the most common non-skin cancer and the second leading cause of cancer-related death in women. In the past fifty years, a woman's lifetime risk of breast cancer more than tripled in the United States, to one in seven today. This trend parallels a staggering increase of chemicals in the environment. Given the increasing number of women in the workforce, it is possible that increases in breast cancer incidence may be caused by occupational exposure. Methods: Application of literature review results of breast cancer risk factors and screening efforts at workplaces to determine the cost-benefit analyses for applications in an occupational medicine practice. Results: Review of epidemiologic studies on suspected environmental risk factors for breast cancer shows that at risk populations can readily be found in the workplace. Effective screening efforts by occupational medicine physicians can reduce mortality in the workforce. Although, conclusions drawn here are limited, it is advisable to develop national policies to reduce chemical exposures that may be associated with breast cancer. Conclusions: Occupational physicians may be an important and appropriate healthcare provider with the opportunity to screen on at risk population, (workforce- female from 18- 65) and influence a wide range of well established and suspected environmental risk factors for breast cancer by incorporating prevention into occupational medicine clinic visits. Mammography and the clinical breast exam have a potential to detect suspicious lesions and may be implemented in occupational medicine clinics. Integrating screening into pre-employment or periodic examinations would expend minimal time and reasonable expenses while potentially preventing worker mortality. The integration of breast cancer screening into occupational medicine may simultaneously improve worker health and increase the value of the occupational medicine physician.

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