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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.
391

An evaluation of a pilot school-based "Mighty heart health promotion program" for primary school students.

January 2006 (has links)
Cheung Yuk Lin Porky. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 236-248). / Abstracts in English and Chinese; appendices also in Chinese. / Acknowledgements --- p.i / Abstract --- p.ii / 論文摘要 --- p.iv / Table of Contents --- p.vi / List of Figures --- p.xii / List of Tables --- p.xiii / List of Abbreviations --- p.xix / Presentations --- p.xx / Chapter CHAPTER 1: --- INTRODUCTION --- p.1 / Chapter 1.1 --- Overview on Childhood Obesity --- p.1 / Chapter 1.1.1 --- Worldwide Situation --- p.1 / Chapter 1.1.2 --- Hong Kong Situation --- p.3 / Chapter 1.2 --- Consequences of Childhood Obesity --- p.4 / Chapter 1.2.1 --- Physiological Problems --- p.4 / Chapter 1.2.2 --- Psychosocial Problems --- p.6 / Chapter 1.2.3 --- Economic Problems --- p.6 / Chapter 1.3 --- Possible Causes and Associated Factors of Childhood Obesity --- p.7 / Chapter 1.3.1 --- Genetics --- p.7 / Chapter 1.3.2 --- Lifestyle Patterns --- p.8 / Chapter 1.3.2.1 --- Physical Activity --- p.8 / Chapter 1.3.2.2 --- Dietary Factors --- p.8 / Chapter 1.3.3 --- Environmental Influence --- p.10 / Chapter 1.3.3.1 --- Parental Influence and Home Environment --- p.10 / Chapter 1.3.3.2 --- Other External Environmental Factors --- p.10 / Chapter 1.4 --- Prevention and Treatment of Childhood Obesity --- p.12 / Chapter 1.4.1 --- Clinical Trials --- p.12 / Chapter 1.4.2 --- Family Based Interventions --- p.13 / Chapter 1.4.3. --- School Based Interventions --- p.14 / Chapter 1.4.4 --- Other Possible Measures --- p.17 / Chapter 1.5 --- Local Intervention Implementation --- p.17 / Chapter 1.6 --- "Study Rationale, Design,Aims and Objectives" --- p.18 / Chapter 1.6.1 --- Study Rationale --- p.18 / Chapter 1.6.2 --- Study Design --- p.19 / Chapter 1.6.3 --- Study Aims and Objectives --- p.21 / Chapter 1.7 --- Conceptual Framework and Hypothesis --- p.21 / Chapter 1.7.1 --- Conceptual Framework --- p.22 / Chapter 1.7.2 --- Hypothesis --- p.23 / Chapter CHAPTER 2: --- METHODOLOGY --- p.23 / Chapter 2.1 --- Sample --- p.23 / Chapter 2.1.1 --- School Recruitment --- p.23 / Chapter 2.1.2 --- Subject Recruitment --- p.23 / Chapter 2.2 --- Parental Consent --- p.24 / Chapter 2.3 --- Focus Groups --- p.24 / Chapter 2.4 --- Assessment Tools --- p.25 / Chapter 2.4.1 --- Weight and Height measures --- p.25 / Chapter 2.4.2 --- Physical Fitness Tests --- p.25 / Chapter 2.4.3 --- Student Questionnaire --- p.26 / Chapter 2.4.4 --- Parental Questionnaire --- p.27 / Chapter 2.4.5 --- Questionnaires Pre-testing --- p.27 / Chapter 2.5 --- Intervention --- p.28 / Chapter 2.5.1 --- Intervention A: Mighty Heart Health Promotion Program --- p.28 / Chapter 2.5.1.1 --- Materials --- p.28 / Chapter 2.5.1.2 --- Procedures --- p.30 / Chapter 2.5.2 --- Intervention B: Health Club --- p.31 / Chapter 2.5.2.1 --- Materials --- p.31 / Chapter 2.5.2.2 --- Procedures --- p.32 / Chapter 2.6 --- Evaluation --- p.35 / Chapter 2.6.1 --- Qualitative Evaluation --- p.35 / Chapter 2.6.2 --- Quantitative Evaluation --- p.35 / Chapter 2.7 --- Data Manasement --- p.36 / Chapter 2.8 --- Statistics --- p.37 / Chapter 2.8.1 --- Health Knowledge and Food Preferences Scores of Students --- p.37 / Chapter 2.8.2 --- "Health Knowledge, Dietary Habits and Home Food Availability Scores of Parents" --- p.40 / Chapter 2.9 --- Ethical Approval --- p.42 / Chapter CHAPTER 3: --- RESULTS --- p.43 / Chapter PART A: --- Baseline Focus Groups Results / Chapter 3.1 --- Baseline Focus Groups Results --- p.43 / Chapter 3.1.1 --- General Description of Participants --- p.44 / Chapter 3.1.2 --- "Views of ""Health"" held by students" --- p.44 / Chapter 3.1.3 --- "Views of ""Health"" of parents" --- p.45 / Chapter 3.1.4 --- "Views of ""Healthy Eating"" of students" --- p.46 / Chapter 3.1.5 --- "Views of ""Healthy Eating"" held by parents" --- p.47 / Chapter 3.1.6 --- "Perceived views on ""Physical Activity"" by students" --- p.48 / Chapter 3.1.7 --- "Views on ""Physical Activity"" of parents" --- p.49 / Chapter 3.1.8 --- Preferred delivery mode of activities communication channels --- p.50 / Chapter PART B: --- Baseline Profile of Participants / Chapter 3.2 --- Response Rate --- p.52 / Chapter 3.3 --- Baseline Characteristics and Socio-dem ograph ic Profile of Participants --- p.54 / Chapter 3.3.1 --- Students --- p.54 / Chapter 3.3.2 --- Parents --- p.56 / Chapter 3.4 --- "Self-perceived Important Values, Health and Weight Status at baseline" --- p.60 / Chapter 3.4.1 --- Students --- p.60 / Chapter 3.4.2 --- Parents --- p.62 / Chapter 3.5 --- Baseline Physical Activity --- p.63 / Chapter 3.5.1 --- Students --- p.63 / Chapter 3.5.2 --- Parents --- p.69 / Chapter 3.6 --- Baseline Dietary Aspects --- p.71 / Chapter 3.6.1 --- Students --- p.71 / Chapter 3.6.2 --- Parents --- p.81 / Chapter 3.7 --- Summary of Baseline associations between students,and parents 'parameters --- p.94 / Chapter 3.7.1 --- Factors associated with Students' weight status --- p.94 / Chapter 3.7.2. --- Factors associated with Studente´ة Dietary Habits --- p.97 / Chapter 3.7.3 --- Factors associated with students´ة physical Activity Habits --- p.104 / Chapter 3.8 --- Summary of Baseline Profile of Participants --- p.108 / Chapter PART C: --- Outcome Evaluation / Chapter 3.9 --- The Final MH activities Conducted --- p.111 / Chapter 3.10 --- Comparisons of Weight Status --- p.112 / Chapter 3.11 --- Comparisons of Self-perceived Health Status and Important Values --- p.114 / Chapter 3.12 --- Comparisons of Physical Activity Parameters --- p.118 / Chapter 3.12.1 --- Students --- p.118 / Chapter 3.12.2 --- Parents --- p.126 / Chapter 3.13 --- Comparisons of Dietary and Health Related Aspects --- p.129 / Chapter 3.13.1 --- Students --- p.129 / Chapter 3.13.2 --- Parents --- p.148 / Chapter 3.13.3 --- Home Food and Meal Environments --- p.167 / Chapter PART D: --- Results of Health Club / Chapter 3.14 --- Baseline Profile of the Participants --- p.180 / Chapter 3.14.1 --- Characteristics and Health Status --- p.180 / Chapter 3.14.2 --- Baseline Physical Activity --- p.181 / Chapter 3.14.3 --- Baseline Dietary Related Parameters --- p.183 / Chapter 3.15 --- The Final HC Lessons Conducted --- p.187 / Chapter 3.16 --- Outcome Evaluation of HC program --- p.188 / Chapter 3.16.1 --- Physical Fitness and Anthropometric Parameters --- p.188 / Chapter 3.16.2 --- Self-perceived Health Status and Important Values --- p.192 / Chapter 3.16.3 --- Physical Activity Related Aspects --- p.193 / Chapter 3.16.4 --- Dietary Aspects --- p.196 / Chapter 3.17 --- Summary of results of the HC Program --- p.201 / Chapter PART E: --- Process Evaluation / Chapter 3.18 --- Process Evaluations of Mighty Heart --- p.203 / Chapter 3.18.1 --- Students --- p.203 / Chapter 3.18.1.1 --- Comments on Program Activities and Materials --- p.203 / Chapter 3.18.1.2 --- Comments on Program Effectiveness and Acceptability --- p.204 / Chapter 3.18.1.3 --- Overall Comments and Suggestions --- p.204 / Chapter 3.18.2 --- Teachers --- p.205 / Chapter 3.18.2.1 --- Comments on Program Activities and Materials --- p.205 / Chapter 3.18.2.2 --- Comments on Program Effectiveness and Acceptability --- p.205 / Chapter 3.18.2.3 --- Overall Comments and suggestions --- p.206 / Chapter 3.19 --- Process Evaluations of the Health Club --- p.207 / Chapter 3.19.1 --- Students --- p.207 / Chapter 3.19.1.1 --- Comments on Program Activities and Materials --- p.207 / Chapter 3.19.1.2 --- Comments on Program Effectiveness and Acceptability --- p.208 / Chapter 3.19.1.3 --- Overall Comments and Suggestions --- p.208 / Chapter 3.19.2 --- Teacher --- p.209 / Chapter 3.19.2.1 --- "Comments on Program Activities, Educational Materials/Resources" --- p.209 / Chapter 3.19.2.2 --- Comments on Program Effectiveness and Acceptability --- p.210 / Chapter 3.19.2.3 --- Overall Comments and Suggestions --- p.211 / Chapter Chapter 4: --- Discussion --- p.212 / Chapter 4.1 --- Overall Effects of the MH Program --- p.213 / Chapter 4.1.1 --- Changes in PA-related Aspects --- p.213 / Chapter 4.1.2 --- Changes in Dietary-related Aspects --- p.216 / Chapter 4.1.3 --- Changes in Health Status related Aspects --- p.225 / Chapter 4.1.4 --- Acceptability and Appropriateness of the MH --- p.225 / Chapter 4.2 --- Overall Effects of the HC Program --- p.226 / Chapter 4.2.1 --- Changes in PA Related Aspects --- p.226 / Chapter 4.2.2 --- Changes in Dietary-related Aspects --- p.227 / Chapter 4.2.3 --- Changes in Health Status related Aspects --- p.228 / Chapter 4.2.4 --- Acceptability and Appropriateness of the HC --- p.229 / Chapter 4.3 --- Strengths and Limitations of the Study --- p.231 / Chapter 4.4 --- Implications and Recommendations for Future Research --- p.233 / Chapter Chapter 5: --- Conclusions --- p.234 / References --- p.236 / Appendix A Principal/ teacher Questionnaire --- p.249 / Appendix B Consent form for parents --- p.252 / Appendix C Focus group questionnaire - Students --- p.258 / Appendix D Focus group questionnaire - Parents --- p.262 / Appendix E Survey questionnaire -Students --- p.266 / Appendix F Survey Questionnaire - Parents --- p.274 / Appendix G Powerpoint material for teachers´ة monthly sharing --- p.282 / Appendix H Working sheets --- p.283 / Appendix I Newsletters for parents --- p.287 / Appendix J Teachers´ة guide for the “Mighty Heart´حprogram --- p.302 / Appendix K Teachers' guide for Health Club --- p.307 / Appendix L The student workbook --- p.311 / "Appendix M Discussion guide for students participating in the ""Mighty Heart ""program" --- p.312 / Appendix N Discussion guide for students participating in the Health Club --- p.313 / Appendix O Discussion guide for teachers conducting the Mighty Heart program --- p.314 / Appendix P Discussion guide for the teachers conducting the Health Club --- p.316
392

Epidemiology, prevention and control of hand, foot, and mouth disease in Hong Kong. / CUHK electronic theses & dissertations collection

January 2013 (has links)
Background / Hand, foot, and mouth disease (HFMD), in particular those associated with enterovirus 71 (EV71), has caused large outbreaks in the Western Pacific and Southeast Asian countries in the past three decades. There is currently no effective chemoprophylaxis or vaccination for HFMD or EV71 infection. Public health strategies rest on good understanding of the epidemiological features of HFMD. The present series of studies examined the epidemiological characteristics of HFMD in Hong Kong, with a view to better understand the disease epidemiology so as to guide public health actions. / Methods and results of individual studies / Study (1)--characterizing the changing epidemiological features identified from various surveillance systems for HFMD / The trend of HFMD activities from 2001-2009 was analyzed using the sentinel surveillance statistics and HFMD outbreaks. The type of institutions reporting HFMD over time, incidences of outbreaks in 18 districts, and age and sex distribution of affected persons of HFMD outbreaks were analyzed. The clinical presentation, hospitalization rate, complication rate and case fatality of outbreaks were examined. The circulating enterovirues each year were determined by laboratory surveillance findings from 2001-2009 and test for morbidity caused by EV71. Seasonal peak was detected from warmer months of May through July but a smaller winter peak was found from October to December since 2006. An increasing trend of more older children aged above 5 years were infected, from 25.4% in 2001 to 33.0% in 2009 (p=0.01, Mantel-Haenszel Chi-square test). Laboratory surveillance detected a cyclical high activity of EV71 in every 3 to 4 years, which was associated with a higher average hospitalization rate among patients of the HFMD outbreaks reported in corresponding year, although it was only marginally significant (p=0.09, linear regression test). / Study (2)--analyzing the characteristics of EV71 epidemic in 2008 / All EV71 cases diagnosed by PHLC from 1998-2008 were analyzed. The complication and case fatality rates, percentage requiring hospitalization, median duration of hospital care, and the likelihood of being associated with an HMFD outbreak in institution in 2008 were compared with the corresponding rates calculated from cases reported from 1998-2007. Phylogenetic tree was constructed by using the neighbour-joining method and the molecular epidemiology of EV71 detected in 2008 was compared with the past years’ trends. Ninety-eight EV71 cases were reported in 2008, highest in the past decade. The annual incidence was 1.4/100 000 in general population, with highest incidence reported in children aged 0-4 years old (27.9/100 000). 11.2% had complications including meningitis or encephalitis (6.1%), pneumonia (3.1%), acute flaccid paralysis (1.0%), and shock (1.0%). There was only one fatal case (CFR: 1.0%) attributed to interstitial pneumonitis. 45.9% had concurrent HFMD outbreaks in their schools or institutions, and six schools required temporarily class suspension for 14 days. Both the complication rate and CFR werenot significantly different from the corresponding rates of the past 10 years (p=0.12 and 1.00 respectively). Phylogenetic analysis found that most cases reported in 2008 were C4 strains, which were the predominant circulating strains in the past ten years. / Study (3)--examining the association between meteorological parameters and HFMD activity / The sentinel consultation rate of HFMD was tested for any association with the meteorological parameters obtained from the Hong Kong Observatory from 2000-2004. Different regression models were examined to find the best model for predicting HFMD consultation rates from 2005-2009. In multivariate regression analysis, model M2 (in which mean temperature, diurnal difference in temperature, relative humidity and wind speed were positively associated with HFMD) was found to have a higher R2 (0.119) than M0 and M1 models with an R2 of 0.079 and 0.062 respectively, indicating that HFMD consultation rates were better explained using meteorological parameters measured 2 weeks earlier. The predicted trend of HFMD consultation rates for 2005 to 2009 matched well with the observed one (Spearman’s rank correlation coefficient=0.276, P=0.000). Sensitivity analysis showed that the estimated HFMD consultation rates were mostly affected by varying the relative humidity and least affected by wind speed. / Study (4)--determining the basic reproduction number of coxsackievirus A16 and enterovirus 71 using mathematical model / The basic reproduction numbers (R0) of EV71 and CoxA16 from laboratory confirmed HFMD outbreaks reported to DH from 2004-2009 were determined using mathematical model. Thirty four outbreaks were analyzed, 27 due to CoxA16 and seven due to EV71. The median R0 of EV71 was 5.48 with an inter-quartile range of 4.206.51 while median R0 of CoxA16 was 2.50 with an inter-quartile range of 1.963.67. In the sensitivity analysis, R0 of EV71 was significantly higher than that of CoxA16 in whole range of incubation periods, p≦0.025. R0was not associated with outbreak setting, size of the institution or number of persons affected. / Study (5)--assessing the impact of SARS and pandemic influenza H1N1 on transmission of HFMD in Hong Kong / I compared the observed HFMD consultation rates and the projected rates, which were constructed using mathematical model, in defined periods of 2003 and 2009 during which territory-wide public health interventions (including school closure) against Severe Acute Respiratory Syndrome (SARS) and pandemic influenza H1N1 were implemented. There was a reduction of 57.2% (95% C.I.:53.0-60.7%) in observed HFMD consultation rates during SARS period in 2003 and a reduction of 26.7% (95% C.I.:19.5-32.7%) during pandemic influenza H1N1 period in 2009. In 2003, the projected rates were still lower than the observed rates beyond week 31 until almost the end of the year. On the contrary, in 2009, the observed HFMD consultation rates became comparable to that of the projected rates in August, before the end of the defined intervention period. / Conclusions / This thesis bridges the knowledge gaps regarding epidemiological characteristics of HFMD. The changing epidemiology of HFMD, including the cyclical high activity of EV71 warrants vigilant surveillance of its activity in order to guide preventive measures. I have demonstrated that climate parameters may help predict HFMD activity, which could assist in explaining the winter peak detected in recent years and issuing early warning in the future. The R0 of EV71 and CoxA16 were first determined in the literature and I found that R0 of EV71 was higher than R0 of CoxA16. The reduction of transmission of HFMD during the SARS and H1N1 periods suggested that public health measures are effective in reducing the transmission of enteroviruses. / Ma, Siu Keung. / Thesis (M.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 121-149). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Table of content --- p.ii / Acknowledgements --- p.iv / Abbreviations --- p.v / Caption for Tables --- p.vi / Caption for Figures --- p.viii / Précis --- p.1 / Chapter PART I: --- LITERATURE REVIEW ON HFMD --- p.5 / Chapter Chapter 1. --- Current Understanding of Epidemiology of HFMD --- p.6 / Chapter 1.1 --- Causative agents and virology --- p.6 / Chapter 1.2 --- Clinical presentation and management --- p.8 / Chapter 1.3 --- Geographical distribution and past epidemics --- p.14 / Chapter 1.4 --- Host susceptibility and molecular determinants of neruovirulence --- p.26 / Chapter 1.5 --- Routes of transmission and transmission dynamics --- p.27 / Chapter 1.6 --- Knowledge gap identified from literature review --- p.29 / Chapter PART II: --- STUDIES ON EPIDEMIOLOGY OF HFMD IN HONG KONG --- p.33 / Chapter Chapter 2. --- Study Objectives and Main data source for analysis --- p.34 / Chapter 2.1 --- Aim and objectives of this thesis --- p.34 / Chapter 2.2 --- Sentinel surveillance system for monitoring HFMD activity --- p.35 / Chapter 2.3 --- Institutional outbreaks of HFMD reported to DH . --- p.37 / Chapter 2.4 --- EV 71 infection reported to Department of Health --- p.37 / Chapter 2.5 --- Laboratory surveillance for monitoring enteroviruses --- p.37 / Chapter Chapter 3. --- Study (1)--Characterizing the changing epidemiological features identified from various surveillance systems for HFMD --- p.38 / Chapter Chapter 4. --- Study (2)--Analyzing the epidemic of enterovirus 71 in 2008 and its public health implication to Hong Kong --- p.52 / Chapter Chapter 5. --- Study (3)--Examining the association between meteorological parameters and HFMD activity --- p.67 / Chapter Chapter 6. --- Study (4)--Determining the basic reproduction number of coxsackievirus A16 and enterovirus 71 using mathematical model --- p.85 / Chapter Chapter 7. --- Study (5)--Impact of SARS and Pandemic Influenza H1N1 on transmission of HFMD in Hong Kong --- p.100 / Chapter Chapter 8. --- Conclusion --- p.111 / List of publications related to this thesis --- p.119 / References --- p.121
393

Mainland Chinese women's perception of risk of cervical cancer: a model to understand factors determining cervical screening behavior. / CUHK electronic theses & dissertations collection

January 2010 (has links)
A model was developed in this study to understand women's cervical screening behaviour. It revealed that the interaction among institutional factors, risk appraisal, coping appraisal, and health beliefs and cultural factors contributed to the complex nature of screening behaviour among Chinese women. The institutional component provided the contextual factors within which women perceived the risk of cervical cancer, perceived the practice of cervical screening, and decided to take or not to take cervical screening. Risk appraisal provided the premise factor that induces women to seek coping strategies to reduce or remove the risk. During the process of coping appraisal, women's motivation to have cervical screening could be increased or decreased as the perceived benefits and costs of screening interacted with each other. The importance of the women's health beliefs and cultural factors was reflected in the way that they were affected by their notions of health behaviour and their cultural beliefs about cervical cancer risk and cervical screening participation. Commitment to participate in screening was a reinforcing factor inducing women to take up an offer of cervical screening. / Aim: To explore the knowledge and the perception of the risk of cervical cancer, identify the factors determining cervical screening behaviour, and develop a model to understand cervical screening behaviour among women in mainland China. / Background: Cervical cancer is the most common type of cancer, and is the second most common cause of cancer death in women in mainland China. Cervical screening is the most important intervention for the secondary prevention of cervical cancer. Theories of health behaviour and empirical research highlight risk perception as a significant factor motivating people to opt for cancer screening. However, little is known about the risk perception of cervical cancer and the factors influencing the screening participation of women in mainland China. / Conclusion: This study provides evidence of the complex factors influencing cervical screening behaviour and contributes new knowledge to the understanding of cervical screening behaviour within the Chinese cultural context. It further informs programmes for the promotion of cervical screening among this population. / Methods: A mixed method design consisting of two phases was used, employing both quantitative and qualitative methods of data collection. First, a cross-sectional survey was conducted to collect a baseline assessment of women's knowledge of cervical cancer and screening, their perceptions of the risk of cervical cancer, and the relationship between these factors and their cervical screening behaviour. Findings from this phase also guided the purposive sampling of participants in phase two. / Results: The findings from phase one demonstrated that the availability of an organized screening programme was a major motivator for women to opt for cervical screening. Multivariate analysis shows that having children (OR=2.57, p=0.026), a perception that visiting doctors regularly is important for health (OR-2.66, p=0.025), average (OR-4.84, 1)=0.006) and high levels of knowledge about cervical screening (OR-9.66, p=0.001) were significantly associated with having been screened in the previous three years. / Then in phase two, qualitative research was conducted using semi-structured interviews of 27 women, 16 of whom had been screened and 11 had not. The interview structure was based on an initial analysis of the data from phase one and from a review of the related literature. The data from the interviews were analyzed using latent content analysis, involving an interpretative reading of the symbolism underlying the surface structure in the text. The audio recordings of the interviews were transcribed verbatim in Chinese, and then the key phrases which were important for the objectives of the study were identified. The key phrases and words were grouped according to their commonality of meaning. Then, these groups of data were sorted and classified to create categories and sub-categories, which were mutually exclusive, explicit and accurate without overlapping. / Two themes emerged from the qualitative data from phase two. Theme I was that perceptions of cervical cancer and cervical screening included five categories: the perceived effects of suffering from cervical cancer; the perception of cervical screening; a lack of understanding about cervical cancer and screening; the perceived risk of cervical cancer; and factors related to the cultural beliefs system. Theme II was that the institutional and health care practitioner system included two categories: availability of an organised physical examination programme and the role of the health care practitioner in encouraging cervical screening utilization. / Gu, Can. / Adviser: Chan, Carmen. / Source: Dissertation Abstracts International, Volume: 73-02, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 244-267). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
394

Weight management in Hong Kong Chinese adults. / CUHK electronic theses & dissertations collection / Digital dissertation consortium / ProQuest dissertations and theses

January 2004 (has links)
Sea Man Mei. / "September 2004." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (p. 194-218). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest dissertations and theses, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.
395

Análise de intervenção em séries temporais de dengue e leptospirose da cidade de São Paulo: influência de fatores políticos, administrativos, técnicos e ambientais / Intervention analysis in time series of dengue and leptospirosis of the city of São Paulo: political, administrative, technical and environmental factor impact

Eduardo de Masi 03 June 2014 (has links)
A dengue e a leptospirose estão entre as principais zoonoses de ocorrência no mundo. A primeira pelo elevado potencial epidêmico e a segunda pela alta letalidade. Na cidade de São Paulo, anualmente ocorrem dezenas de casos de leptospirose e centenas de casos de dengue, fazendo desses agravos alguns dos eventos de maior interesse da vigilância em saúde do município. Para melhor compreender o efeito de fenômenos climáticos e o impacto de medidas de prevenção e controle sobre a transmissão desses agravos ao longo do tempo, dois diferentes modelos estatísticos de estudo de séries temporais foram usados: 1) Função de Transferência, com erros dados por modelos ARIMA (ARIMAX), os quais foram modelados segundo a filosofia de Box-Jenkins e 2) Modelos Aditivos Generalizados (GAM) de regressão de Poisson, com estrutura de defasagem dada por funções polinômios PDL (Polynomial Distributed Lags). Os principais fatores climáticos associados ao aumento do número de casos de dengue na cidade de São Paulo foram a elevação da temperatura mínima do ar, dos níveis de precipitação pluviométrica, da densidade do vetor e a entrada de casos importados da doença, estimulada pelo feriado de carnaval. A chegada de frentes frias (temperatura < 16°C) e valores extremos de precipitação ( 70mm) reduzem o número de casos de dengue. Medidas de prevenção adotadas pelas equipes de vigilância em saúde do município também contribuem com a redução do número de casos. Os fatores associados ao aumento do número de casos de leptospirose foram o aumento da precipitação pluviométrica e da temperatura máxima do ar. O aumento das horas de brilho do sol reduz o número de casos. Os métodos adotados foram adequados aos objetivos do estudo e conseguiram captar as relações defasadas entre os fatores de interesse e a transmissão de dengue e de leptospirose na cidade de São Paulo. Tais técnicas também parecem adequadas como ferramentas a serem incorporadas à rotina da vigilância em saúde, permitindo fazer previsões do número de casos futuros e compreender as relações temporais entre as doenças e seus fatores determinantes e condicionantes / Dengue and leptospirosis are among the major zoonosis of occurrence in the world; the first because of the epidemic potential and the second due to high lethality. In São Paulo, dozens of leptospirosis cases and hundreds of dengue fever cases are registered annually, being some of the most important events to the municipal public health surveillance system. To understand the effect of climatic conditions and the impact of measures of prevention and control over the transmission of such diseases in the time context, two time series approaches were used: 1) Transfer Functions, with ARIMA error structure (ARIMAX), modeled by Box-Jenkins methods and 2) Additive Generalized Models (GAM) of Poisson regressions, with time structure given by Polynomial Distributed Lags (PDL). The most important climatic factors that increased the number of cases of dengue fever in the city of São Paulo were the elevation in air temperature, precipitation, vector density and the number of imported cases, which increased after carnival holiday (an important calendar event). The arrival of cold fronts from the south (air temperature < 16°C) and extreme precipitations (70mm) are factors that decrease the number of new dengue cases. The public health preventive interventions adopted by the municipality were effective in diminishing the dengue occurrence. The most important factors that increased the number of leptospirosis cases in São Paulo were elevation in maximum air temperature and precipitation. Largest amount of hours of sunshine decreased the number of new cases of leptospirosis. The methods used were adequate to the study objectives, the relations among the interest lagged factors and dengue and leptospirosis transmission in the city of São Paulo were satisfactorily modeled. Such techniques also seem appropriate as tools to be incorporated into the municipal health surveillance system, allowing the prediction of the number of future disease cases and understanding temporal relations between diseases and their determinants and conditioning factors
396

Risk perceptions, cognitive behavioral models and HIV-related risk behaviors among non-institutionalized male injecting drug users in China. / 中國社區男性靜脈注射吸毒者之風險認知、行為認知理論模型及愛滋病相關高危行為研究 / CUHK electronic theses & dissertations collection / Zhongguo she qu nan xing jing mai zhu she xi du zhe zhi feng xian ren zhi, xing wei ren zhi li lun mo xing ji ai zi bing xiang guan gao wei xing wei yan jiu

January 2010 (has links)
Conclusion. The significance of risk perception in predicting behavioral intention, hence actual future behaviors, is therefore evident. Conditional measures need to be used. HIV prevention can employ conditional risk perception approaches. Health behavioral theories can be strengthened by using such conditional measures on risk perceptions. The results add to this new and growing area of risk behavior research. / Introduction. Risk perception, a core element of key health behavioral theories and health interventions, is assumed to motivate people to avoid risk behaviors. Mixed findings however prevail in the literature due to methodological issues. Many of such studies are cross-sectional, using global risk perception measures that do not condition on type of risk behavior or partnership which may affect the level of risk. / Male injecting drug users (IDU) are driving the HIV epidemic in China and bridge HIV transmission to non-IDU female populations; they may be at risk of both unprotected sex and syringe sharing. HIV prevention targeting male IDU is greatly warranted and would benefit from understanding of the relationships between risk perceptions and behaviors, in the context of health behavioral theories such as the Health Action Process Approach (HAPA) model, which had not been applied to studies targeting IDU. / Objectives. This study refined the concepts and measures of HIV-related risk perception, conditioning on different types of behaviors and partners, and extended it to include others-directed risk perceptions. The relationship between such conditional risk perception measures and both prior risk behaviors and behavioral intention to avoid sex-related and drug-related risk behaviors in the future were investigated and were compared to those involving global unconditional risk perception measures. The nature of the aforementioned relationships, being motivational or reflective was investigated. A longitudinal component validated the predictive power of behavioral intention over actual future behaviors. / Results. Almost 90% of the respondents had had unprotected sex though &lt;20% shared syringes with others in the last 6 months. Prior syringe sharing but not unprotected sex in the last 6 months was significantly associated with global unconditional risk perception measures. The picture is totally different when risk perception measures conditioned on type of sex partner and unprotected sex or syringe sharing were used instead of the global measures---higher levels of the conditional risk perception measures were significantly associated with higher levels of behavioral intention for consistent condom use and avoidance of syringe sharing, thus supporting the motivational hypothesis. Conditional others-directed risk perceptions (perceived risk of transmitting HIV to others via unprotected sex and syringe sharing) were also associated with the aforementioned behavioral intentions to avoid risk behaviors. A pilot longitudinal study showed that behavioral intentions strongly predict actual future behaviors. Other HAPA-based variables such as self-efficacy and outcome expectancies had predictive effects on behavioral intentions, independent from those of risk perceptions. / Subjects and methods. A total of 456 sexually active male IDU were recruited from Dazhou, Sichuan and Hengyang, Hunan, via snowball sampling. With informed consent, anonymous face-to-face interviews were conducted by trained and experienced staff of the local CDC in privacy settings. / Tsui, Hi Yi. / Adviser: Joseph Lau. / Source: Dissertation Abstracts International, Volume: 72-04, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 118-130). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese; appendix in Chinese.
397

Can a preschool health intervention improve preschoolers' lifestyle behaviors and home food environment?.

January 2008 (has links)
Chan, Yun Kwan. / Accompanying CD-ROM contains appendix H, I, J, and K. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 161-170). / Abstracts in English and Chinese; three appendixes in Chinese only. / Library's copy: lacks accompanying CD-ROM. / Acknowledgement --- p.i / Abstract --- p.ii / Abstract (Chinese) --- p.iv / List of publications --- p.vi / Table of Contents --- p.viii / List of Figures --- p.xvi / List of Tables --- p.xvii / List of Abbreviations --- p.xxv / Chapter CHAPTER ONE: --- INTRODUCTION --- p.1 / Chapter 1.1 --- Global prevalence of childhood overweight --- p.1 / Chapter 1.2 --- Preschool health situation in HK --- p.2 / Chapter 1.2.1 --- Breastfeeding --- p.2 / Chapter 1.2.2 --- Diet and physical activity patterns --- p.3 / Chapter 1.2.3 --- Prevalence of childhood overweight --- p.5 / Chapter 1.2.3.1 --- Definition of childhood overweight --- p.5 / Chapter 1.2.3.2 --- Local prevalence of childhood overweight --- p.6 / Chapter 1.3 --- Consequences of childhood overweight --- p.7 / Chapter 1.3.1 --- Health consequences of childhood overweight --- p.7 / Chapter 1.3.2 --- Economic consequences of childhood overweight --- p.9 / Chapter 1.4 --- Risk factors of childhood overweight and obesity --- p.11 / Chapter 1.4.1 --- Family Socioeconomic status --- p.11 / Chapter 1.4.2 --- Parental overweight --- p.11 / Chapter 1.4.3 --- Breastfeeding --- p.12 / Chapter 1.4.4 --- Birth order --- p.13 / Chapter 1.4.5 --- Breakfast consumption --- p.13 / Chapter 1.4.6 --- Beverage consumption --- p.14 / Chapter 1.4.7 --- High calcium intake --- p.15 / Chapter 1.4.8 --- Fruit and vegetable consumption --- p.15 / Chapter 1.4.9 --- Physical inactivity --- p.15 / Chapter 1.4.9.1 --- Physical activity recommendations for preschoolers --- p.17 / Chapter 1.4.9.2 --- Screentime recommendations for preschoolers --- p.18 / Chapter 1.5 --- Child development --- p.18 / Chapter 1.5.1 --- Onset of overweight --- p.18 / Chapter 1.5.2 --- Early establishment of lifelong habits at preschool age --- p.19 / Chapter 1.5.3 --- Interaction with parents --- p.20 / Chapter 1.6 --- Justification of preschool multi-component health intervention in Hong Kong --- p.22 / Chapter 1.6.1 --- Local health promotion initiative at preschool --- p.22 / Chapter 1.6.2 --- Justification for DRAGON2006 modifications --- p.23 / Chapter 1.6.2.1 --- Inclusion of family-home component in school- based health intervention --- p.24 / Chapter 1.6.2.2 --- Child BMI monitoring and health report to parents --- p.24 / Chapter 1.7 --- Present school-based preschool health intervention --- p.25 / Chapter 1.8 --- Summary --- p.27 / Chapter 1.9 --- Aims and objectives --- p.27 / Chapter CHAPTER TWO: --- METHODOLOGY --- p.28 / Chapter 2.1 --- Recruitment of preschools and preschoolers --- p.28 / Chapter 2.2 --- Development of DRAGON2006 --- p.33 / Chapter 2.2.1 --- Ethics approval --- p.35 / Chapter 2.2.2 --- Focus groups with parents --- p.35 / Chapter 2.2.3 --- Amendment and pretest of the questionnaires --- p.35 / Chapter 2.2.4 --- Health lessons --- p.36 / Chapter 2.2.4.1 --- Development and adaptation of the health lessons --- p.36 / Chapter 2.2.4.2 --- Improvement of the teaching materials --- p.37 / Chapter 2.2.4.3 --- Lyrics reproduction and CD production --- p.37 / Chapter 2.2.4.4 --- Worksheets --- p.38 / Chapter 2.2.4.5 --- Process evaluation --- p.38 / Chapter 2.2.5 --- Teachers´ة training --- p.38 / Chapter 2.3 --- Intervention Activities and Components --- p.39 / Chapter 2.3.1 --- Opening ceremony --- p.39 / Chapter 2.3.2 --- Health Talks --- p.40 / Chapter 2.3.3 --- Health report --- p.40 / Chapter 2.3.4 --- Parental newsletters --- p.41 / Chapter 2.4 --- Outcome evaluation --- p.42 / Chapter 2.5 --- Data collection --- p.43 / Chapter 2.5.1 --- Recruitment of subjects --- p.43 / Chapter 2.5.2 --- Anthropometric measurements --- p.43 / Chapter 2.5.3 --- Parental baseline and evaluation questionnaire administration --- p.44 / Chapter 2.5.4 --- Teachers´ة pre- and post-intervention evaluation and process evaluation --- p.44 / Chapter 2.6 --- Data management --- p.44 / Chapter 2.6.1 --- Verification of data from the questionnaires --- p.44 / Chapter 2.6.2 --- Data coding --- p.45 / Chapter 2.6.3 --- Data entry and verification --- p.45 / Chapter 2.6.4 --- Data analysis --- p.45 / Chapter 2.5.4.1 --- Descriptive and association analysis --- p.45 / Chapter 2.5.4.2 --- Construction of BMI-for-age percentile and z- score curves --- p.46 / Chapter 2.5.4.3 --- Evaluation of the effectiveness of the program --- p.47 / Chapter CHAPTER THREE: --- RESULTS --- p.48 / Chapter 3.1 --- Organization of the results --- p.48 / Chapter 3.2 --- Baseline comparability between the EG and CG --- p.48 / Chapter 3.2.1 --- General sociodemographic characteristics --- p.48 / Chapter 3.2.2 --- Preschoolers' diet and meal behaviors --- p.54 / Chapter 3.2.3 --- Preschoolers´ة dental health --- p.61 / Chapter 3.2.4 --- Parental child feeding behaviors --- p.62 / Chapter 3.2.5 --- Preschoolers´ة physical activity and sedentary behaviors --- p.66 / Chapter 3.2.6 --- Summary --- p.67 / Chapter 3.3 --- Baseline comparability between the completes and dropouts --- p.69 / Chapter 3.3.1 --- Participant flow in the EG and CG --- p.69 / Chapter 3.3.2 --- General sociodemographic characteristics --- p.70 / Chapter 3.3.3 --- "Preschoolers´ة diet, meal and physical and sedentary activity behaviors and parental child feeding behaviors" --- p.74 / Chapter 3.3.4 --- Summary --- p.75 / Chapter 3.4. --- Evaluation of the effectiveness of the DRAGON2006 --- p.76 / Chapter 3.4.1 --- General demographic characteristics --- p.76 / Chapter 3.4.2 --- Effects on preschoolers´ة anthropometry and weight status --- p.77 / Chapter 3.4.3 --- Effects on preschoolers' diet and meal behaviors --- p.79 / Chapter 3.4.4 --- Effects on parental child feeding behaviors --- p.89 / Chapter 3.4.5 --- Effects on preschoolers´ة physical and sedentary activities --- p.92 / Chapter 3.4.6 --- Summary --- p.94 / Chapter 3.5 --- "Teaching staff members´ة attitudes, perceptions and practices with respect to addressing childhood overweight" --- p.95 / Chapter 3.5.1 --- General demographic characteristics --- p.95 / Chapter 3.5.2 --- Teachers' attitude toward addressing childhood overweight --- p.98 / Chapter 3.5.3 --- Teachers' behaviors toward addressing childhood overweight --- p.99 / Chapter 3.5.4 --- Teachers' perceived abilities to deal with some childhood overweight topics --- p.100 / Chapter 3.5.5 --- Teachers´ة reported helpful factors to implementing a new preschool health program --- p.101 / Chapter 3.5.6 --- Teachers´ة reported helpful factors for and barriers to parents´ة participation --- p.102 / Chapter 3.5.7 --- Comparisons between staff with and without self-reported weight and height --- p.103 / Chapter 3.5.8 --- Summary --- p.105 / Chapter 3.6 --- EG teachers´ة evaluation of the program --- p.106 / Chapter 3.6.1 --- Teachers' perception of DRAGON2006 program before the intervention --- p.106 / Chapter 3.6.2 --- DRAGON teachers´ة process evaluation of the DRAGON2006 curriculum --- p.113 / Chapter 3.6.3 --- DRAGON teachers´ة evaluation of DRAGON2006 program after the intervention --- p.118 / Chapter CHAPTER FOUR: --- DISCUSSION --- p.127 / Chapter 4.1 --- "Baseline findings about the preschoolers' weight status, diet, meal and physical and sedentary activity situation" --- p.127 / Chapter 4.1.1 --- Preschooler and parental overweight and obesity --- p.127 / Chapter 4.1.2 --- Preschoolers´ة diet and meal behaviors --- p.128 / Chapter 4.1.3 --- Preschoolers´ة physical and sedentary activity behaviors --- p.130 / Chapter 4.2 --- "Gender associations with preschoolers´ة diet, meal and physical and sedentary activity behaviors and parental child feeding behaviors" --- p.131 / Chapter 4.2.1 --- Gender associations with preschoolers´ة diet and meal behaviors --- p.132 / Chapter 4.2.2 --- Gender associations with parental child feeding behaviors --- p.134 / Chapter 4.2.3 --- Gender associations with preschoolers´ة physical and sedentary activity behaviors --- p.135 / Chapter 4.3 --- "Age associations with preschooler diet, meal and physical and sedentary activity behaviors and parental child feeding behaviors" --- p.136 / Chapter 4.3.1 --- Preschoolers' age associations with their anthropometry --- p.137 / Chapter 4.3.2 --- Preschoolers´ة age associations with their diet and meal behaviors --- p.137 / Chapter 4.3.3 --- Preschoolers' age associations with their dental health --- p.139 / Chapter 4.3.4 --- Preschoolers´ة age associations with parental child feeding behaviors --- p.139 / Chapter 4.3.5 --- Preschoolers´ة age associations with their physical and sedentary activity behaviors --- p.140 / Chapter 4.4 --- "Family income associations with preschooler diet, meal and physical and sedentary activity behaviors and parental child feeding behaviors" --- p.141 / Chapter 4.4.1 --- Family income associations with some general demographic characteristics of the sample --- p.143 / Chapter 4.4.2 --- Family income associations with preschoolers´ة diet and meal behaviors --- p.144 / Chapter 4.4.3 --- Family income associations with parental child feeding behaviors --- p.147 / Chapter 4.4.4 --- Family income associations with preschoolers' physical and sedentary activity behaviors --- p.148 / Chapter 4.5 --- Factors associated with preschool overweight and obesity --- p.148 / Chapter 4.5.1 --- Preschooler overweight and obesity associations with some general demographic characteristics of the baseline participants --- p.149 / Chapter 4.5.2 --- Preschooler overweight and obesity associations with parental overweight and obesity --- p.150 / Chapter 4.5.3 --- Preschooler overweight and obesity associations with preschoolers' meal behaviors --- p.150 / Chapter 4.5.4 --- Preschooler overweight and obesity associations with their physical and sedentary activity behaviors --- p.150 / Chapter 4.6 --- The evaluation of the effectiveness of DRAGON2006 --- p.151 / Chapter 4.6.1 --- Baseline comparison between the education (EG) and control group (CG) --- p.151 / Chapter 4.6.2 --- Baseline comparison between completers and dropouts --- p.151 / Chapter 4.6.3 --- Follow up comparison between the education (EG) and control groups (CG) --- p.152 / Chapter 4.6.3.1 --- The changes in preschooler anthropometry --- p.153 / Chapter 4.6.3.2 --- The changes in preschooler diet and meal behaviors --- p.154 / Chapter 4.6.3.3 --- The changes in preschooler physical and sedentary activity behaviors --- p.155 / Chapter 4.6.3.4 --- Parental child feeding behaviors --- p.156 / Chapter 4.7 --- The teachers´ة evaluation results of DRAGON2006 and of Color Me Healthy --- p.156 / Chapter 4.7 --- Strengths and limitations of the study --- p.157 / Chapter 4.8 --- Suggestions for improvement of DRAGON --- p.159 / Chapter CHAPTER FIVE: --- CONCLUSION --- p.160 / References --- p.161 / Appendices / Chapter AI --- Invitation letter for preschool (English) --- p.171 / Chapter AIII --- Invitation letter for preschool (Chinese) --- p.172 / Chapter AIII --- Invitation letter for CG preschool (Chinese only) --- p.173 / Chapter BI --- Research proposal (English) --- p.174 / Chapter BII --- Research proposal (Chinese) --- p.178 / Chapter CI --- Purpose and structure of DRAGON2006 health lessons (English) --- p.181 / Chapter CII --- Purpose and structure of DRAGON2006 health lessons (Chinese) --- p.185 / Chapter DI --- Teacher evaluation Part A (pre-intervention) (English) --- p.189 / Chapter DII --- Teacher evaluation Part A (pre-intervention) (Chinese) --- p.191 / Chapter EI --- Teacher evaluation Part B (process evaluation) (English) --- p.193 / Chapter EII --- Teacher evaluation Part B (process evaluation) (Chinese) --- p.205 / Chapter FI --- Teacher evaluation Part C (post-intervention) (English) --- p.218 / Chapter FII --- Teacher evaluation Part C (post-intervention) (Chinese) --- p.222 / Chapter GI --- Child health report (English) --- p.224 / Chapter GII --- Child health report (Chinese) --- p.226 / Chapter H --- Teaching kit --- p.228 / Chapter I --- Music sound track --- p.228 / Chapter J --- Curriculum worksheets (Chinese only) --- p.228 / Chapter K --- Parents´ة newsletters (Chinese only) --- p.228 / Chapter LI --- Focus group study questions (English) --- p.229 / Chapter LII --- Focus group study questions (Chinese) --- p.231 / Chapter MI --- Consent form for EG parents (English) --- p.233 / Chapter MII --- Consent form for EG parents (Chinese) --- p.235 / Chapter MII --- Consent form for CG parents (English) --- p.237 / Chapter MI --- Consent form for CG parents (Chinese) --- p.238 / Chapter NI --- Pre-internvetion parental questionnaire (English) --- p.239 / Chapter NII --- Pre-intervention parental questionnaire (Chinese) --- p.245 / Chapter OI --- Post-intervention parental questionnaire (English) --- p.250 / Chapter OII --- Post-internvetion parental questionnaire (Chinese) --- p.256 / Chapter PI --- Post-intervention staff survey (English) --- p.262 / Chapter PII --- Post-intervention staff survey (Chinese) --- p.264 / Chapter Q --- "Gender differences in preschoolers´ة diet, meal, physical and sedentary behaviors and parental child feeding behaviors" --- p.266 / Chapter R --- "Age differences in preschoolers´ة diet, meal, physical and sedentary behaviors and parental child feeding behaviors" --- p.296 / Chapter S --- "Income differences in preschoolers' diet, meal, physical and sedentary behaviors and parental child feeding behaviors" --- p.313 / Chapter T --- Factors associated with preschooler weight status --- p.334 / Chapter U --- "Maternal education level differences in preschoolers´ة diet, meal, physical and sedentary behaviors and parental child feeding behaviors" --- p.352 / Chapter V --- "Maternal birth place differences in preschoolers´ة diet, meal, physical and sedentary behaviors and parental child feeding behaviors" --- p.374 / Chapter W --- Test-retest reliability of DRAGON2006 questionnaire --- p.394
398

Epidemic modeling for travel restrictions on the pandemic influenza A (H1N1). / CUHK electronic theses & dissertations collection

January 2011 (has links)
Chong, Ka Chun. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 125-141). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
399

Fuel load characterisation and quantification for the development of fuel models for Pinus patula in South Africa

Ross, Timothy Ian 12 1900 (has links)
Thesis (MScBosb)--University of Stellenbosch, 2004. / ENGLISH ABSTRACT: The characteristics and total fuel load of the forest floor (FF) and harvest residue (HR) are needed to develop tools that can be used for fuel load management, fire risk analysis and fire behaviour prediction for P. patula grown in the summer rainfall area of South Africa (SA). Forest floor depth, mass and ash-free mass were measured and there was generally a greater range in depth under sawtimber (ST) stands than under pulpwood (PLP) stands. Forest floor loads, prior to ashing, ranged from 21 - 168 t ha-1 and 27 - 72 t ha-1, for ST and PLP stands, respectively and loads increased linearly with stand age. Sawtimber and PLP stands were analysed together, which resulted in a significant correlation between depth and mass (r2 = 0.78, n = 31). A loss on ignition procedure carried out on sub-samples of the FF improved the relationship between the FF depth and the ash-free mass for the different stands, and provided a more accurate model for the prediction of mass from depth. A multiple regression analysis revealed that age, altitude and mean annual precipitation (MAP) provided the best subset and accounted for 72% of the variation in the FF mass observed. The effect of increasing FF load and increasing moisture content on the fireline intensity (FLI) was examined using the fire behaviour prediction programme, BehavePlus. Harvest residue was quantified and characterised in terms of fuel size classes, under current silvicultural regimes for ST and PLP, for the development of fuel models for this species over its planted range in SA. An investigation into the proportion (by mass) of the 1- (0.0 - 0.6 cm), 10- (0.6 – 2.5 cm), 100- (2.5 – 7.6 cm) and 1000-hr (> 7.6 cm diameter) fuel classes of the total HR mass indicated that there was a significant difference between the mass of the 1-, 10- and 1000-hr fuel classes of the two silvicultural regimes, and no significant difference for the 100-hr fuel class. Two fuel models for P. patula HR and two models for standing timber were developed using the new model (NEWMDL) programme of BEHAVE and tested in BehavePlus. Nutrient concentrations were used with FF layer and HR size class load data to estimate the quantities of nutrients held in the fuel and to describe nutrient distributions in the fuel complex. Significant differences in the nutrient concentration of the FF layers and fuel components were observed which has important implications for fuel management. The concentration of N determined in this study, relative to that determined in other similar studies on P. patula was low. Forest floor loads were predicted and nutrient pools calculated for typical ST and PLP stands at both low and high altitude to provide insight into the nutrient distributions within the fuel complex. / AFRIKAANSE OPSOMMING: Die karaktereienskappe en totale brandstoflading van die bosvloer (FF) en kaalkap oorskot (HR) word benodig om instrumente te ontwikkel wat gebruik kan word vir brandstoflading bestuur, brandgevaar ontleding en brandgedrag voorspelling vir P. patula, wat in die somer reënvalgebied van Suid-Afrika groei. Die bosvloer diepte, massa en asvrye massa is gemeet en daar was oor die algemeen ‘n groter variasie in diepte onder saaghout (ST) opstande as onder pulphout (PLP) opstande. Die bosvloerladings, voor verassing, het varieer van 21 – 168 t ha-1 en 27 – 72 t ha-1 vir ST en PLP opstande respektiwelik. Ladings het linieêr vermeerder met opstand ouderdom. Saaghout en PLP opstande is saam geanaliseer en het tot ‘n betekenisvolle korrelasie gelei tussen diepte en massa (r2 = 0.78, n = 31). ‘n Verliestydens- ontbranding prosedure is uitgevoer op die FF monsters en het die verhouding tussen FF diepte en die asvrye massa van die verskillende opstande verbeter. Dit het ook gelei tot akkurater model vir die voorspelling van massa vanaf diepte. ‘n Veelvoudige regressie analise het aan die lig gebring dat ouderdom, hoogte en gemiddelde jaarlikse reënval (MAP) die beste sub-groep verskaf, en het 72% van die variasie in die FF massa verklaar. Ondersoek is ingestel op die effek van toenemende FF lading en toenemende voginhoud op die brandlyn intensiteit (FLI) deur die brandgedrag program, BehavePlus, toe te pas. Die kaalkap oorskot is gekwantifiseer en gekarakteriseer volgens brandstof grootteklasse, onder die huidige boskultuurstelsels vir ST en PLP, vir die ontwikkeling van brandstofmodelle vir hierdie spesie oor die betrokke groeistreek in SA. ‘n Ondersoek in die verhouding (volgens massa) van die 1- (0.0 – 0.6 cm), 10- (0.6 – 2.5 cm), 100- (2.5 – 7.6 cm) en 1000-uur (> 7.6 cm deursnee) brandstofklasse van die totale HR massa het aangedui dat daar ‘n betekenisvolle verskil is tussen die massas van die 1-, 10- en 1000-uur brandstofklasse van die twee boskultuurstelsels, en geen betekenisvolle verskil vir die 100- uur brandstofklas nie. Twee brandstofmodelle is ontwikkel vir P. patula HR en twee modelle vir staande hout deur gebruik te maak van die nuwe model (NEWMDL) program van BEHAVE en getoets in BehavePlus. Voedingstof konsentrasies is gebruik, tesame met die FF laag en HR klasgrootte ladingdata, om die voedingstof inhoud van die brandstof te skat en om die voedingstof verspreiding te beskryf in die brandstofkompleks. Betekenisvolle verskille is waargeneem in die voedingstof konsentrasies van die FF lae en brandstof komponente wat belangrike implikasies inhou vir brandstofbestuur. Die konsentrasie wat vir N in hierdie studie bepaal is, was laag relatief tot ander soortgelyke studies vir P. patula. Die bosvloer ladings is voorspel en voedingstofpoele bereken vir tipiese ST en PLP opstande vir beide lae en hoë hoogtes om insig te verkry, sodat insig verkry kon word in die voedingstof verspreidings binne die brandstofkompleks.
400

Relationship between work and non-work stressors and work-life balance amongst global market trading professionals

De Sousa, Michelle Fontainha 11 1900 (has links)
In the financial industry, there is a high demand for employees to possess all the necessary skills and motivation to perform highly specialized functions, and handle demands that accompany increasing stress levels. The aim of the research was to determine whether there is a relationship between work and non-work stressors and work-life balance in the Global Market Trading industry. A cross-sectional survey design was used, with a sample of 72 global market trading professionals drawn from a financial institution in Gauteng. Two questionnaires and a biographical questionnaire were administered. The questionnaires proved to be reliable. The power of the study was calculated. Descriptive statistics and Spearman correlation was used to organise, summarise and describe the data. The findings of the study show that as global market trading professional’s intrinsic factors at work and stress regarding their personal time increases, their experience of negative WHI increase as well. / Industrial and Organisational Psychology / M.Com. (Industrial and Organisational Psychology )

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