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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.
421

The Epidemiology and Surveillance of Ciguatera Fish Poisoning in the Turks and Caicos Islands

Schneider, Evan 11 September 2012 (has links)
Innovative ways to conduct disease surveillance are required to address the complexity of Ciguatera Fish Poisoning (CFP). Mixed methods were employed to explore CFP epidemiology and interdisciplinary approaches to its surveillance in the Turks and Caicos Islands (TCI). Quantitative analyses of cross-sectional data collected by the TCI’s National Epidemiology and Research Unit in 2010 demonstrated that a low percentage of residents reported lifetime histories of illness following fish consumption (3.9%). Furthermore, gender, age, island, and home remedy use were significantly associated with reported clinic visitation by ill individuals. Next, a multisectoral CFP surveillance model was conceptualized. A qualitative exploration of the model’s hypothetical integration into TCI’s health system revealed that several systemic and contextual factors could influence the future uptake of interdisciplinary CFP surveillance. Targeted interventions are recommended to improve national CFP surveillance and to facilitate the growth of interdisciplinary networks between stakeholders from TCI’s health, fisheries and environment sectors. / Canadian Institutes of Health Research, Ontario Veterinary College, University of Guelph, Ministry of Health and Human Resources of the Turks and Caicos
422

The development of executive function in children exposed to alcohol in utero: An exploratory study.

Badenhorst, Tania. January 2008 (has links)
<p><font face="Times New Roman" size="3"><font face="Times New Roman" size="3"> <p align="left">The study made use of cross-sectional design that compared the performance of younger children (6- to 7-year-olds) with that of older children (12- to 13-year-olds) on various measures of executive function. Within this, it made use of a natural experimental design, with children exposed to alcohol<i><font face="Times New Roman" size="3"> as the experimental group and non-exposed children as the control group.</font></i></p> </font></font></p>
423

Smoking behaviour, risk perception and attitude to anti-smoking legislation among students at the University of the Western Cape

Popovac, Masa January 2010 (has links)
The study investigated three aspects related to smoking, namely, smoking behaviour, risk perception and attitudes to anti-smoking legislation. The theoretical framework of the study was the Information-Motivation-Behavioural (IMB) skills model. The study was a quantitative one, making use of a cross-sectional survey design to obtain data about the three variables of interest. Responses to statements about risk perception and attitudes to anti-smoking legislation in the questionnaire were arranged on a three-point Likert scale. The inferential statistics used were one-sample ttests and Chi-square analyses. The results showed an overall smoking prevalence of 16%, with twice as many females than males being smokers in the sample. ‘Coloured’ students in both genders had the highest smoking rate compared to all other race groups. The knowledge of the health risks of smoking were very high, however smokers had a lower perception of risk compared to non-smokers. Moreover, while there was a fair amount of support for anti-smoking legislation among smokers, smokers tended to show less support for legislation than non-smokers, especially to those parts of the legislation that affect them more directly. The results of the study indicate a clear connection between smoking behaviour and the effect it has on both risk perception as well as attitudes to anti-smoking legislation in individuals.
424

Work-related low back pain among clinical nurses in Tanzania.

Mwilila, Mary Chandeu. January 2008 (has links)
<p>Low back pain (LBP) is a significant problem among the nursing population worldwide. Manual lifting and shifting of heavy objects and patients are primary contributing factors. Nurses are supposed to be knowledgeable about the risk factors and preventive measures and effectively apply it into practice to prevent them from sustaining back injuries. Strategies to reducing the incidences of LBP in nurses have been previously implemented but with little outcomes. The purpose of this study was to explore the relationship between occupational risk factors and the prevalence of LBP in nurses at MOI, Tanzania. Therefore, the study examined / the prevalence of LBP amongst nurses, work-related risk factors contributing to LBP, knowledge and effectiveness of back care techniques, and barriers to effective back care techniques in clinical nurses.</p>
425

Dental anxiety among 15-year-olds : Psychosocial factors and oral health

Stenebrand, Agneta January 2015 (has links)
AIM: The overall aim of this thesis was to examine the associations between dental anxiety, experiences of dental care, psychosocial factors and oral health among 15-year-olds, and to analyse changes in the prevalence of dental anxiety over time. MATERIALS AND METHODS: The thesis was based on two cross-sectional epidemiological studies in Jönköping, Sweden. Papers I, II, and III were based on a random sample of 15-year-old individuals. The total sample consisted of 221 individuals. Six questionnaires were used, one included items of background data, while the others were psychometric instruments measuring dental anxiety, temperament, general anxiety and depression, general fearfulness and attitudes to dental care. Paper IV was based on the Jönköping studies, a series of epidemiological studies from 1973, 1983, 1993, and 2003 in which random samples of 15-year-old individuals were included. The total sample consisted of 405 individuals. Questionnaires including background data and dental anxiety were used and clinical data were collected. RESULTS: Of the 15-year-old individuals 6.5% were classified as dentally anxious with girls proportionally more fearful than boys (Papers I-III). Dental anxiety correlated significantly with three of the temperament dimensions; emotionality, activity and impulsivity. Reported pain or unpleasant experiences during dental care treatment were clear predictors concerning dental anxiety (Paper I). Both symptoms of general anxiety and depression were significantly correlated with dental anxiety after controlling for other potential risk factors (Paper II). Dental anxiety was associated with both general fearfulness and with attitudes to dental care, where the strongest predictor of dental anxiety was general fearfulness (Paper III). A trend analysis over the 30-year period showed a gradient of statistically significantly decreasing dental anxiety prevalence, from 38.1% in 1973 to 12.8% in 2003. Over the period the 15-year-old individuals with dental anxiety had significantly higher number of filled tooth-surfaces than those with no dental anxiety, and also more caries in 1973. There were no such differences concerning plaque and gingivitis (Paper IV). CONCLUSIONS: Dental anxiety in 15-year-olds correlated with experiences of dental care, psychosocial factors as well as to oral health. Specifically, pain experiences related to dental care, attitudes to dental care and general fearfulness seem to have the strongest impact on dental anxiety. Dental anxiety showed a clear declining change over time. More girls than boys reported dental anxiety. The thesis shows that dental care providers need paying attention on providing a supportive dental care situation, in which the patients should not experience pain. One part may be adequate local anaesthesia during operative dentistry or similar dental treatments. Another part may be a good oral health to prevent negative experiences of dental care. There is a need for the understanding of psychological factors associated with dental care procedures. / SYFTE: Det övergripande syftet med denna avhandling var att bland 15-åringar undersöka sambanden mellan tandvårdsrädsla, erfarenheter av tandvård, psykosociala faktorer och oral hälsa, samt att analysera förändringar i förekomsten av tandvårdsrädsla över tid. MATERIAL OCH METOD: Avhandlingen baseraspå två epidemiologiska tvärsnittsstudier i Jönköping. I arbete I, II och III redovisas studier av 221 slumpmässigt utvalda 15-åriga individer. Deltagarna besvarade frågor avseende bakgrundsdata, tandvårdsrädsla, temperament, ångest och depression, generell rädsla samt attityder till tandvård. Arbete IV bygger på Jönköpingsstudierna, från 1973, 1983, 1993, och 2003, där sammanlagt 405 slumpmässigt utvalda 15-åriga individer ingick. Datainsamling gjordes med hjälp av frågeformulär, bestående av bakgrundsdata och tandvårdsrädsla, samt kliniska data. RESULTAT: Resultatet i arbete I, II och III visade att 6,5% av ungdomarna rapporterade hög tandvårdsrädsla, där en övervägande andel var flickor. I arbete I visade tandvårdsrädsla samband med tre av temperamenten; emotionalitet, aktivitet och impulsivitet. Rapporterad smärta eller obehagliga upplevelser under tandbehandling var tydliga prediktorer avseende tandvårdsrädsla. I arbete II visade både symtom på ångest och depression samband med tandvårdsrädsla, sedan effekterna av andra potentiella riskfaktorer hade kontrollerats för statistiskt. I arbete III visade tandvårdsrädsla starkt samband med både generell rädsla och med attityder till tandvård, där den starkaste prediktorn för tandvårdsrädsla var generell rädsla. I arbete IV visade en trendanalys en statistiskt säkerställd minskning gällande förekomsten av tandvårdsrädsla, från 38,1% år 1973 till 12,8% år 2003. Ungdomarna med tandvårdsrädsla hade signifikant fler fyllda tandytor än ungdomarna utan tandvårdsrädsla under 30-årsperioden, och år 1973 även mer karies. Det fanns inga sådana skillnader avseende plack och gingivit. SLUTSATSER: Resultatet visar att tandvårdsrädsla är relaterat till smärtsamma erfarenheter av tandvård, generell rädsla, och oral hälsa. Resultatet visar också att tandvårdsrädsla hos 15-åringar har minskat över tid och är vanligare hos flickor. Resultaten pekar på att tandvårdspersonalen har en viktig uppgift i att unga tandvårdspatienter inte utsätts för smärtsam behandling. Framtida forskning av intresse kan vara hur olika sätt att administrera lokalbedövning kan förändra uppfattningen av smärta och nivåer av tandvårdsrädsla.
426

Multi-Unit Longitudinal Models with Random Coefficients and Patterned Correlation Structure: Modelling Issues

Ledolter, Johannes January 1999 (has links) (PDF)
The class of models which is studied in this paper, multi-unit longitudinal models, combines both the cross-sectional and the longitudinal aspects of observations. Many empirical investigations involve the analysis of data structures that are both cross-sectional (observations are taken on several units at a specific time period or at a specific location) and longitudinal (observations on the same unit are taken over time or space). Multi-unit longitudinal data structures arise in economics and business where panels of subjects are studied over time, biostatistics where groups of patients on different treatments are observed over time, and in situations where data are taken over time and space. Modelling issues in multi-unit longitudinal models with random coefficients and patterned correlation structure are illustrated in the context of two data sets. The first data set deals with short time series data on annual death rates and alcohol consumption for twenty-five European countries. The second data set deals with glaceologic time series data on snow temperature at 14 different locations within a small glacier in the Austrian Alps. A practical model building approach, consisting of model specification, estimation, and diagnostic checking, is outlined. (author's abstract) / Series: Forschungsberichte / Institut für Statistik
427

Lower selenium status among adult white American males: prevalence, risk factors, and identification of augmentation strategies: a potential approach to reduce prostate cancer incidence

Pinfold, Andrew James 01 May 2008 (has links)
Abstract Objectives: To establish the prevalence of lower serum selenium status (<106 ng/ml) among the adult white American male population, to determine whether certain social, economic, geographic, physical, and dietary characteristics are risk factors for lower selenium status, and to identify a selenium augmentation strategy for white adult men deficient in this trace element. Design: An exploratory cross-sectional study using nationally representative data from the National Health and Nutrition Examination Survey III, 1988-1994 (NHANES III). Methods: 2989 white men, aged 20 or greater in the NHANES III dataset had recorded serum selenium values. These men were divided in two groups based on selenium status, those with values of less than 106 ng/ml (n=288) and those with a status greater than or equal to 106 ng/ml (n=2701). Various demographic, physical, and dietary variables were then compared between the two selenium status groups in a bivariate analysis. Multiple logistic regression was then performed to assess possible risk factors for lower selenium status. Results: This study estimated that 7.7% of white American adult men aged 20 years and older, a total of 4,751,618 individuals, had a selenium status less than 106 ng/ml. Several, of the more than forty, social, economic, geographic, physical and dietary characteristics examined were shown to be significantly associated with a lower selenium status. Risk factors for lower selenium status (<106 ng/ml) were, smoking, living in the Southern census region, being in either the 20-39 or the 60 years or older age groups, exercising less than their peers, having a lower income, and not consuming dark bread. Conclusion: It would appear that certain physical, geographic, dietary and demographic characteristics are significantly associated with lower selenium status. While, this work was unable to identify a suitable selenium fortification vehicle to reduce the prevalence of lower selenium status, it did identify risk factors that may contribute to this condition.
428

Sapwood Amount and its Predictive Equations for Young Hinoki Cypress (Chamaecyparis obtusa) Trees

ADU-BREDU, Stephen, HAGIHARA, Akio, 萩原, 秋男 12 1900 (has links) (PDF)
農林水産研究情報センターで作成したPDFファイルを使用している。
429

Design, maintenance and methodology for analysing longitudinal social surveys, including applications

Domrow, Nathan Craig January 2007 (has links)
This thesis describes the design, maintenance and statistical analysis involved in undertaking a Longitudinal Survey. A longitudinal survey (or study) obtains observations or responses from individuals over several times over a defined period. This enables the direct study of changes in an individual's response over time. In particular, it distinguishes an individual's change over time from the baseline differences among individuals within the initial panel (or cohort). This is not possible in a cross-sectional study. As such, longitudinal surveys give correlated responses within individuals. Longitudinal studies therefore require different considerations for sample design and selection and analysis from standard cross-sectional studies. This thesis looks at the methodology for analysing social surveys. Most social surveys comprise of variables described as categorical variables. This thesis outlines the process of sample design and selection, interviewing and analysis for a longitudinal study. Emphasis is given to categorical response data typical of a survey. Included in this thesis are examples relating to the Goodna Longitudinal Survey and the Longitudinal Survey of Immigrants to Australia (LSIA). Analysis in this thesis also utilises data collected from these surveys. The Goodna Longitudinal Survey was conducted by the Queensland Office of Economic and Statistical Research (a portfolio office within Queensland Treasury) and began in 2002. It ran for two years whereby two waves of responses were collected.
430

A modified obesity proneness model in the prediction of weight status among high school students

Nickelson, Joyce E. January 2008 (has links)
Dissertation (Ph.D.)--University of South Florida, 2008. / Title from PDF of title page. Document formatted into pages; contains 118 pages. Includes vita. Includes bibliographical references.

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