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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.
11

The ENCOURAGEing workplaces project: the addition of a fitness based health risk assessment to a physical activity counseling intervention

Hamm, Naomi 13 September 2016 (has links)
There has been a large growth in workplace wellness initiatives; however, use of fitness based health risk assessments (fHRAs) remains largely unexplored. I hypothesized that adding an fHRA to a physical activity counseling intervention (PAC+HRA) would greater increase physical activity levels compared to physical activity counseling alone (PAC). A 4 month, two- group quasi-experimental design was used to test this hypothesis. Over time, there was an increase in total, moderate to vigorous, and moderate physical activity ≥10-minute bouts. Self-Efficacy for Exercise increased and symptoms of depression decreased. Subgroup analysis of the PAC+HRA group found a significant improvement in overall fitness levels. Participants progressed to more advanced stages of change. In conclusion, PAC+HRA did not increase physical activity levels more than PAC. This is likely due to the characteristics of the counseling, fHRA, and outcome measurements. / October 2016
12

Characterization, bioavailability and health risk assessment of mercury in dust impacted by gold mining

Yalala, Bongani Ndhlovu 25 May 2015 (has links)
A Thesis submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy 2015. / Gold mining in South Africa has been the backbone of the economy for many years. With it came economic well-being, the growth and development of satellite towns, cities and metropolitan cities, e.g. Johannesburg-a place of gold. Unfortunately, it also came with adverse effects, most of which are now evident, after a century of mining, with little or no regard for pollution prevention or any form of remediation. Of interest, in this study, is the presence of tailings storage facilities (TSFs) found within the residential areas, in close proximity to commercial district and industry, having been built around them. Currently, some 270 TSFs lie dormant, pregnant with vast number of toxic heavy metals from the initially low efficient but selective gold processing techniques. This led to the deposition of the sand dumps, with high sulphur, iron, chromium, cadmium, arsenic, and mercury amongst other toxic metals. Exposure to oxygen, and water, the pyrites were oxidized and formed acid mine drainage (AMD), which resulted in the leaching out all toxic heavy metals into ground water and surface water causing serious water pollution and environmental degradation. Due to the low efficient gold processing technique, some gold amount was discarded together with the tailings materials. The reprocessing of these dumps led to the generation of dust, which is easily distributed over large areas of land. The unrehabilitated, semi-rehabilitated, and the abandoned TSFs contributed to all forms of pollution, majorly, windblown dust from unprotected tops and sides, AMD leaching toxic heavy metals. In this study, mercury, one of the most toxic elements found within the vast TSFs was determined. This was carried out as part of a larger environmental impact assessment on the effects and scale of pollution from the gold mining in the Witwatersrand. The study area consisted of the greater Johannesburg area, covering commercial business district (CBD), the industrial areas (Aeroton, City Deep, Germiston, Selby, Springs), and the residential areas (Alberton, Boksburg, Centurion, Germiston, Greenside, Sandton, Springs). Dust samples were collected from paved surfaces in the streets, and accessible buildings, were sieved into three sieved into three fractions (PM100, PM50, PM25), and most of the work focused on the smallest size fraction (PM25) in order to study impact of inhalable and respirable dust. Three sequential extraction procedures (modified BCR-the European Community Bureau of Reference, selective sequential procedure (SSE), and novel sequential extraction procedure (n-SEP)) were applied for partitioning and evaluating the mobility, availability and persistence of mercury in urban dusts. Bioavailability of mercury was assessed by leaching dust with artificial gastric and lung fluids which mimicked body conditions. Contamination levels were assessed based on the enrichment factor (EF), contamination factor (Cf) and geoaccumulation index (Igeo) were calculated to further assess the environmental risk and provide a preliminary estimate of the main sources of mercury in street dust. Non-carcinogenic effects and carcinogenic effects due to exposure to urban street dusts were assessed for both children and adults. The total mercury (HgTOT) ranged from 269 to 1350 μg kg-1. In the PM25 size fraction, mercury exhibited the following decreasing order of HgTOT: industrial area > CBD > residential area. This order shows that the HgTOT concentration in the street dust decreased with increased distance from the TSFs. The highlight was that the highest HgTOT was reported in industrial areas next to the TSFs, tailings reprocessing areas, and tailings footprints. Furthermore, in residential areas grossly affected by TSFs and tailings reprocessing, reported high HgTOT values similar to those reported for industrial samples. These results indicated that the presence of TSFs were largely responsible for the mercury found in the dust. The results from the characterization of the dust showed a large concentration of fine particulate matter, with the characteristically high quartz (74 – 98 wt. %), and minor minerals phases such as chloritoid, chlorite, K-feldspar, jarosite, mica, muscovite, pyrite, and pyrophyllite, all below 10 wt. %. These have been known to enrich trace metals, hence a high concentration of mercury. The close proximity of the tailings to the communities led to the determination of bioavailability of mercury from dust. The bioaccessible Hg extracted by lung fluid (up to 3% of HgTOT) was higher than that of gastric fluid (up to 1% of HgTOT) and was related to the mobile pool of Hg in dust. This suggests that human exposure to Hg in dust via inhalation is greater than that via the gastric tract. These values were very similar to the values obtained from water soluble phase in the sequential extraction procedure (average 1.4% of HgTOT). This indicated that these fluids were able to extract the most bioavailable fraction of Hg, which is responsible for most of the transformation reactions involving mercury. Contamination assessment factor was carried out to classify the pollution levels and indicate whether they are from natural or anthropogenic sources. Based on the EF, Cf, and Igeo, 70, 82, and 84% of the street dust samples were classified as heavily enriched, very highly contaminated, and strongly polluted by mercury, respectively, indicating that they are of anthropogenic origin. The human health risk model was useful in identifying the areas of health risks from exposure to mercury pollution. It showed that children were more vulnerable than adults when exposed to mercury in dust via ingestion. The cancer risk for exposure to As, Cd, and Cr by both children and adults was significantly high for oral ingestion of dust. Cr (VI) was the highest contributor followed by As and lastly Cd. For inhalation pathway, the possibility of developing cancer after a lifetime exposure was low and below the acceptable limits (10-6).
13

Adolescent Social Motives: Measurement and Implications

Flournoy, John 11 January 2019 (has links)
The study of decision making during adolescence has received considerable attention throughout the history of developmental psychology, justifiably, given the marked increases in morbidity and mortality that belie otherwise robust health. Although the dominant theories invoked to help explain decision-making during adolescence acknowledge the existence of motivations that are thought to be central to this developmental period, there is little work that investigates the effects of these motives, per se. In particular, motivations toward developing sexual and romantic relationships, as well as toward navigating peer status hierarchies have both been acknowledged as especially relevant for this period of development. Almost all research in this area focuses on self-report, and is heavily weighted toward the domain of status and popularity. A major gap in this literature is an understanding of how adolescent-relevant motivations affect basic behavioral processes, and of the consequences of individual differences in motivations. The current investigation uses reinforcement learning to examine the effects of social motives on stimulus salience. This may allow both indirect, behavioral measurement of motivations, and is itself a potential mechanism by which motivations affect behavior via experience of the environment, and learning. Adolescent (N = 104) and college student (N = 230) participants learned four social-motive-relevant, and two baseline face-word associations. Learning was characterized using both proportion of optimal responses in the last half of the learning task, and a Rescorla-Wagner-like computational model. Results showed greater learning, and higher learning rates, in the social-motive conditions. In order to explore the validity of behavior on the task as a measure of particular motivations, individual learning differences between social and baseline conditions were compared with developmental indices, self-report traits, and self-report health-relevant behaviors. Older participants were better at the learning task, but social-motive learning enhancement was constant across development. Measures of social-motive effects on learning did not correlate with self-reported traits or health-related behaviors. The effects of motive-relevant words on learning may be due to factors unrelated to motivation, but research design may also be problematic. Self-report trait instruments performed well, but a more comprehensive taxonomy of motivational constructs and measures would be beneficial.
14

Attityder hos lastbilsförare gällande mat i samband med långa, korta -respektive blandade transportsträckor

Martinez Lopez, Alejandro January 2012 (has links)
Martinez, A (2011). Attityder hos lastbilsförare gällande mat i samband med långa -respektive korta transportsträckor. Akademin för hälsa och arbetsliv, Högskolan i Gävle.   AbstractBackground: The profession as a lorry driver is in many aspects very risky. Factors such as time directive, poor diet and shift work characterize the profession and puts drivers' health at risk. Current research shows that the vast majority of lorry drivers are overweight, suffer from high stress related to work and have on average a very low consumption of fruits and vegetables. All these factors may be associated with increased risk of cardiovascular disease, type 2 diabetes, obesity, and impaired quality of life. Purpose: To investigate the attitudes of the lorry drivers regarding food and meals in connection with the long, short and combined distances.Materials: A convenience sample was used in connection with this study, as professional drivers are a difficult study target. A total of 50 lorry drivers with three different professional backgrounds were investigated, long distance, distribution (short) and combined driving. In total the loss amounted to ten drivers, which means a shortfall of 20 percent.Design and Methods: A cross-sectional study was used as a diagnostic method for the analysis of individual factors in relation to attitudes. The above quantitative design was chosen because it effectively facilitates the study of large groups. Data collection was conducted with a questionnaire consisting of 21 questions. All questions were graded from 1-7 using the Likert- scale, which is a useful grading tool for attitudes and is also the correct scale level in relationship to this study. Results: The results show that there are no significant differences in attitudes between drivers who drive long, short – or combined distances. In addition the independent variables, do not affect the results. However, the driver’s exhibit similar attitude settings for individual study factors and the results show that there is a neutral attitude toward the social aspect of meals, while “mood” as a factor during food consumption is very important.Discussion: In order to improve lorry drivers working conditions and attitudes to food in a work setting, it requires knowledge of the individual factors that influence the attitudes of the profession. Attitudes are an important part of individual decision making and behavior. By examining the attitudes of lorry drivers on individual factors we can effectively streamline public health efforts to improve this vulnerable profession. Further research is needed to investigate the underlying and individual factors that determine the lorry driver’s food choices in relationship to work, however, this study can also be used in the continuing effort to improve lorry driver’s health and wellbeing.   Keywords: Lorry drivers, food, nutrition and health risk / I tid och otid
15

Gesundheitsrisiken inhalierter Partikel / Effects of inhaled particles on human health

Koch, Thea, Spieth, Peter 04 September 2007 (has links) (PDF)
Although not all hazardous effects on human health have been clearly defined so far, the health risks of particulate matter can be considered evident. Pulmonary and cardiovascular diseases, in particular, are caused or aggravated by inhaled particulate matter. The aim of this article is to describe the incorporation and the effects on organ function of inhaled particles. Furthermore, the potential risks of de novo synthesised nanoparticles are discussed in the context of the public controversy regarding environmental particulate matter pollution. / Obwohl die schädlichen Auswirkungen inhalierbarer Partikel auf unseren Organismus bisher noch nicht vollständig geklärt sind, kann eine Gesundheitsgefährdung durch Feinstäube als erwiesen angesehen werden. Insbesondere pulmonale und kardiovaskuläre Erkrankungen werden durch Feinstaubexposition ausgelöst oder verschlimmert. Dieser Artikel stellt Aufnahme und Auswirkungen inhalierter Partikel im menschlichen Organismus dar und erörtert potenzielle Gefahren de novo synthetisierter Nanopartikel im Kontext der auch in der breiten Öffentlichkeit kontrovers geführten Feinstaubdiskussion.
16

The relationship between maternal depression, adolescent depression, and engagement in health-risk behaviours

Wickham, Maeve E. Unknown Date
No description available.
17

An analysis of health promoting and risky behaviours of health science students of the University of the Western Cape.

Steyl, Tania. January 2007 (has links)
<p>Assessing and understanding the health needs and abilities of university and college students is vital in creating healthy campus communities. Student learning is a central part of the higher education academic mission, and health promotion serves this mission by supporting students and creating healthy learning environments. Findings from various studies suggest that students entering the university setting put themselves at risk through unhealthy behaviours. Health science students are the future health professionals who will teach health promotion and disease prevention. The aim of this study was to determine and analyse health risk behaviours and health promoting behaviours among health science students at the University of the Western Cape. The study further aimed to identify the factors influencing these students' engagement in these risk behaviours.</p>
18

A critical review of languages of risk, with implications for public health /

Burge, Julie Patricia. January 1999 (has links) (PDF)
Thesis (M.P.H.) -- University of Adelaide, Dept. of Public Health, 2000? / Bibliography: leaves 195-205.
19

Willingness to pay for health risk reductions : the importance of scenario adjustment, household structure and type of disease /

Johnson, Erica H. January 2009 (has links)
Typescript. Includes vita and abstract. Includes bibliographical references (leaves 146-150). Also available online in Scholars' Bank; and in ProQuest, free to University of Oregon users.
20

Risk assessment model to predict foodborne illness outbreaks at restaurants

Sato, Heidi D. January 1900 (has links)
Thesis (Ph.D.)--Touro University International, 2007. / Adviser: Marc Strassburg. Includes bibliographical references.

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