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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.
101

Construction project manager health and safety interventions towards improving workers' performance

Ayessaki, Winn-Yam Houdou January 2016 (has links)
Optimum construction worker (CW) performance is required to achieve project delivery within project parameters. It is not always the case as CWs are regularly exposed to hazards, involved in accidents, their productivity is poor, they suffer from ill health, suffer from work-related musculoskeletal disorders (WMSDs) and contractors lack resources to allocate towards H&S. However, the lack or the absence of health and safety (H&S) measures, which the aforementioned depend on, has a negative impact on workers’ performance. Two descriptive surveys were conducted among professional construction project managers (CPMs) registered with the South African Council for Project and Construction Management Professions (SACPCMP) and general contractors (GCs) registered with the East Cape Master Builders Association (ECMBA). Interviews were also conducted with CPMs registered with the SACPCMP residing in the Nelson Mandela Bay metropolitan area. The salient findings include: • Accidents, which occur on construction sites, impact workers’ performance; • Inadequate H&S implementation affects both CW skills and motivation, which in turn affects their performance; • Poor constructability is relevant to H&S and CWs’ skills; • Provision and maintenance of welfare facilities are commonly inadequate and affect workers’ performance, and • Projects do not benefit from the adequate financial provision for H&S. It was concluded that exposure to hazards, poor site conditions, inadequate provision of welfare facilities, WMSDs, and insufficient financial provision for H&S affect workers’ performance by either incapacitating or demotivating them. Recommendations include : CPMs should make better use of their influence on clients; they should improve communication channels between project stakeholders; legislators need to raise awareness regarding H&S and worker welfare, and training and education institutions need to empower workers and professionals with H&S knowledge.
102

Effects of methylmercury on reproduction and offspring development and potential benefits of supplemental selenium and vitamin E intake in rats

Beyrouty, Peter. January 2002 (has links)
No description available.
103

Interactions of nutrients on methyl mercury toxicity in neuron X spinal chord hybrid cells (NSC-34) and human oligodendrocyte X rhabdomyosarcoma cells (MO3.13)

Chapman, Laurie A. January 2001 (has links)
No description available.
104

An investigation of safety syringes in the prevention of needlestick injuries

Kroes, Gabriel 12 1900 (has links)
Thesis (MBA)--Stellenbosch University, 2001. / ENGLISH ABSTRACT: Daily more than 300 000 health care workers in South Africa are to a lesser or greater extent exposed to the risk of deadly viruses which can be transferred through neediestick injuries. It is estimated that currently 9,8 million people in South Africa are HIV positive. This high incidence of HIV has a great impact on the danger of infection from neediestick injuries. It is estimated that 44 000 neediestick injuries takes place annually in South Africa. Despite such a high risk there are currently few safety regulations or official efforts to prevent or determine the true impact and incidence of needlesticks in South Africa. This study project investigated the number of neediestick injuries that could potentially be prevented by the use of needles with safety features and estimated the ranges of benefits and costs of using such safety devices. With the financial constraints that are imposed on South African hospitals, infection control through the use of safety syringes makes economic sense. Prevention of infections is clearly far cheaper than cure. / AFRIKAANSE OPSOMMING: Daagliks word meer as 300 000 gesondheids personeel in Suid Afrika in 'n mindere of meerdere mate blootgestel aan die risiko van lewens gevaarlike viruse wat deur middel van naaldprik ongelukke oorgedra kan word. Hierdie risiko word spesifiek in Suid Afrika verhoog deur die hoë insidensie van HIV. Dit word beraam dat daar tans 9,8 miljoen mense in Suid Afrika is wat HIV positief is. Daar word beraam dat daar tans 44 000 naaldprik ongelukke per jaar in Suid Afrika plaasvind. Ten spyte van die hierdie hoë risko is daar tans min veiligheids regulasies of amptelike pogings om die omvang en voorkoming van naaldprik insidente te bepaal nie. Hierdie studie het die getal naaldprikke wat voorkom kan word deur die gebruik van veiligheids inspuitnaalde ondersoek en het die voordele en kostes van sulke veiligheidsmaatreëls beraam. Gegewe die finasiële druk wat ons tans in Suid Afrikaanse hospitale ondervind, is bewys dat die gebruik van veiligheids inspuitnaalde ekonomiese sin maak. Voorkoming op hierdie manier is bewys as 'n ver goedkoper opsie as nasorg.
105

Health status of children left behind in Sichuan rural areas :a cross-sectional study

Choi, Weng I January 2018 (has links)
University of Macau / Institute of Chinese Medical Sciences
106

The post-occupancy evaluation of a green star SA certified building in order to determine the internal environmental quality effectiveness.

Nibakuze, Noella. January 2013 (has links)
Thesis (MTech. degree in Architectural Technology)--Tshwane University of Technology, 2013. / The aim of this study was to conduct a Post-Occupancy Evaluation (POE) of a Green Star SA certified office building in order to determine to what extent this building performs in terms of the Internal Environmental Quality (IEQ) from the perspective of the occupants as well as the effect of POE on the occupants' health and productivity. The objectives were to measure employees' satisfaction with the IEQ in a green building; to determine whether the health of the occupants is satisfactory in a green building; and to determine whether the health of the employees and their perceived productivity are influenced by IEQ in a green building.
107

A proposed pathophysiological role for TNFa in obesity induced cardiac hypertrophy

Rostami, Maryam 03 1900 (has links)
The a of TNFa in title is the Greek alpha. / Thesis (MSc)--University of Stellenbosch, 2002. / ENGLISH ABSTRACT: Background: Cardiac hypertrophy is an adaptive process occurring in response to mechanical overload or tissue injury. The stimuli for cardiac hypertrophy are diverse and vary from increased afterload on the heart to cardiac remodeling in response to cytokines. Amongst others, obesity is characterized by excessive body weight resulting in metabolic disorders. This excess body weight necessitates an increased blood and oxygen delivery to the peripheral tissues, which is achieved by an elevated cardiac output. Total blood volume is also increased in the obese due to the increased tissue volume and vascularity. With time, the obesity induced increase in cardiac preload results in left ventricular hypertrophy and dilatation. Obesity is also associated with complications such as hypertension, insulin resistance and impaired glucose metabolism. In addition, adipose tissue has been implicated to contribute to elevated circulating TNFa levels in obesity and may contribute to the pathophysiology of the heart in obese individuals. The heart is a major cytokine-producing organ that generates amongst others tumor necrosis factor a (TNFa). TNFa is a proinflammatory cytokine, which acts to increase its own production, has cytotoxic and cytostatic effects on certain tumor cells and influences growth and differentiation in virtually all cell types including cardiomyocytes. Elevated levels of TNFa are detected peripherally in almost all forms of cardiac injury and in hypertrophic cardiomyopathy. These elevations are proposed to be deleterious to the heart, although an adaptive role for low levels of TNFa has been proposed. Aim: The aim of the study was to determine whether there is a correlation between obesity and serum, myocardial, and adipose tissue TNFa levels and cardiac hypertrophy. We also wished to determine whether the hearts from the obese animals functioned normally under normoxic conditions and whether they responded differently to ischaemia/reperfusion when compared with their concurrent controls. Materials and Methods: Male Sprague-Dawley rats (n=100) were fed a high caloric diet (HCD) containing 33% rat chow, 33% condensed milk, 7% sucrose and 27% water, or standard laboratory rat chow for 6-12 weeks. Food consumption, body weight gain, heart weight and tibia length were measured. Serum glucose, insulin and lipid levels were also determined. Hearts were excised and perfused on the isolated Working Heart perfusion apparatus and cardiac function was monitored and documented. Hearts were then subjected to 15 minutes of total global ischaemia at 370C, and reperfused for 30 minutes. Cardiac function was again documented. A separate series of hearts were freeze-clamped at different time points during the experimental protocol and stored in liquid nitrogen for the determination of myocardial TNFa and cGMP levels. Serum TNFa levels were determined after 12 weeks on the high caloric or normal/control diet. After 12 weeks on the diet myocardial TNFa levels of the HCD fed animals and their concurrent controls were determined before and during ischaemia. Adipose tissue and myocardial tissue TNFa levels were also determined after 6, 9 and 12 weeks on the respective diets. Myocardial cGMP levels were measured in the HCD fed rats and the control rats after 6, 9, and 12 weeks. These data were used as an indirect index to determine whether the myocardial NOcGMP pathway was activated in the normoxic hearts on the respective diets. Results: The body weight of the HCO fed animals was significantly higher compared with their respective controls after 12 weeks on the diet (459.9 ± 173.8 g and 271.5 ± 102.6 g respectively (p<0.05». The HCO fed animals also had heart weight to body weight ratios that were significantly greater compared with the controls (4.2 ± 0.1 mglg and 3.7 ± 0.1 mglg respectively (p<0.05». The plasma glucose levels of the HCO fed animals were higher than their respective controls (9.2 ± 0.3 mmoiII and 7.8 ± 0.3 mmoiII respectively (p<0.05)), but their insulin levels were similar (12.87 ± 1.02 IlIUlml and 12.42 ± 5.06 IlIU/ml). Plasma lipid profiles (plasma cholesterol, high density lipoprotein (HOL) cholesterol and plasma triacylglyceride (TAG)) were abnormal in the HCO fed animals compared with the control rats. Plasma TAG levels in the HCO fed animals were significantly higher compared with the control rats (0.664 ± 0.062 mmoiII and 0.503 ± 0.043 (p<0.05», while plasma cholesterol levels (1.794 ± 0.058 mmoIII and 2.082 ± 0.062 mmoiII (p<0.05» and HOL cholesterol levels were significantly lower (1.207 ± 0.031 mmoiII and 1.451 ± 0.050 mmoiII (p<0.05». Cardiac mechanical function was similar for both groups before ischaemia, but the percentage aortic output recovery was lower for the hearts from the HCO fed animals when compared with their controls (47.86 ± 7.87% and 66.67 ± 3.76 % respectively (p<0.05». Serum TNFa levels of the HCO fed animals were higher compared with the control animals (51.04 ± 5.14 AU and 31.46 ± 3.72 AU respectively (p<0.05», but myocardial TNFa levels remained lower in these animals (312.0 ± 44.7 pglgram ww and 571.4 ± 132.9 pg/gram ww respectively (p<0.05)). During ischaemia these myocardial TNFa levels increased above those of the controls (442.9 ± 12.4 pg/gram ww and 410.0 ± 12.5 pg/gram ww respectively (p<0.05)). The adipose tissue TNFa levels were significantly increased after 12 weeks on the high caloric diet compared with the control animals (4.4 ± 0.4 pg/gram ww and 2.5 ± 0.3 pg/gram ww respectively (p<0.05)). There was no significant difference in the myocardial cGMP levels of the HCD rats compared with the conrol rats after 6, 9 and 12 weeks. Conclusion: 1) The high caloric diet induced obesity, which lead to cardiac hypertrophy in this study. 2) There was a strong correlation between elevated adipose tissue and serum TNFa levels, and cardiac hypertrophy. 3) Elevated serum TNFa levels did not lead to activation of the myocardial NO-cGMP pathway in the normoxic hearts in this model. 4) The hypertrophied hearts from the HCD fed animals had poorer post-ischaemie myocardial functions than their concurrent controls. / AFRIKAANSE OPSOMMING: Agtergrond: Miokardiale hipertrofie is In aanpassing wat gebeur as In gevolg van meganiese oorbelading of weefsel beskadiging. Verskillende stimuli kan tot miokardiale hipertrofie aanleiding gee soos byvoorbeeld In verhoging in nalading, of miokardiale hermodellering in respons op sitokiene. Verhoging van voorbelading in vetsug mag ook tot hipertrofie aanleiding gee. Vetsug word gekenmerk deur In oormatige liggaamsmassa wat tot metaboliese versteurings lei. Die oormatige liggaamsmassa vereis In verhoging in bloed- en suurstofverskaffing aan die perifere weefsel wat deur In verhoging in die kardiale uitset vermag kan word. Die bloed volume van In vetsugtige individu word ook verhoog as gevolg van In verhoging in weefselvolume en vaskulariteit en met verloop van tyd induseer die verhoogde kardiale voorbelading linker ventrikulêre hipertrofie en dilatasie. Vetsug word ook met verskeie ander siekte toestande soos hipertensie, insulien weerstandigheid en versteurde glukose metabolisme, geassosieer. Vetweefsel dra ook by tot verhoging van tumor nekrose faktor alfa (TNFa) vlakke in die bloed, wat op sy beurt tot miokardiale hipertrofie mag bydra. TNFa is In proinflammatoriese sitokien wat sy eie produksie kan stimuleer. Dit het ook sitotoksiese en sitostatiese effekte op sekere tumor selle en kan groei en differensiasie in bykans alle seltipes, insluitende kardiomiosiete, stimuleer. Die hart kan ook TNFa produseer en verhoogde TNFa vlakke word feitlik in alle vorms van miokardiale besering en hipertrofiese kardiomiopatie waargeneem. Daar word voorgestel dat verhoogde TNFa vlakke vir die hart nadelig is, ten spyte van die vermoeding dat die sitokien In potensiële aanpassings rol by laer vlakke het. Doelstelling: Die doel van hierdie studie was om vas te stelof daar 'n verband tussen vetsug en serum, miokardiale en vetweefsel TNFa vlakke en miokardiale hipertrofie, bestaan. Ons het ook gepoog om te bepaal of harte van vetsugtige diere normaal funksioneer en of die response van sulke harte op isgemie-herperfusie van die van ooreenstemmende kontroles verskil. Materiaal en tegnieke: Manlike Sprague-Dawley rotte (n=100) is vir 6-12 weke op 'n hoë kalorie dieët (HKD) geplaas. Die HKD het uit 33% rotkos, 33% gekondenseerde melk, 7% sukrose en 27% water bestaan. Kontrole diere het standaard laboratorium rotkos ontvang. Voedselinname, liggaamsmassa toename, serum insulien, glukose en lipied vlakke is ook bepaal. Harte is geïsoleer en geperfuseer volgens die Werk Hart perfusie metode en hart funksie is gemonitor en gedokumenteer. Harte is vervolgens aan 15 minute globale isgemie by 3rC blootgestel en daarna weer vir 30 minute geherperfuseer waartydens hartfunksie weer gedokumenteer is. 'n Aparte groep harte is op spesifieke tydsintervalle gedurende die eksperimentele protokol gevriesklamp en in vloeibare stikstof gestoor vir die bepaling van miokardiale TNFa en sGMP vlakke. Serum TNFa vlakke is bepaal na 12 weke op die dieët. Na die diere 12 weke op die HKD was, is hierdie diere en hulooreenstemmende kontroles se miokardiale TNFa vlakke voor en na isgemie bepaal. Vetweefsel en miokardiale TNFa vlakke is ook onderskeidelik na 6, 9 en 12 weke bepaal. Miokardiale sGMP vlakke is in die HKD diere en in die kontrole diere na 6, 9 en 12 weke bepaal. sGMP vlakke is gebruik as 'n indirekte indeks van aktivering van die miokardiale NO-sGMP boodskapper pad. Resultate: Na 12 weke op die dieët was die liggaamsmassa van die HKD diere beduidend hoër in vergeleke met hulooreenstemmende kontroles (459.9 ± 173.8 g en 271.5 ± 102.6 g (p<0.05)). Die HKD diere se hart massa tot liggaam massa verhouding was ook beduidend hoër in vergelyking met die van kontroles (4.2 ± 0.1 mglg en 3.7 ± 0.1 mglg (p<0.05)). Alhoewel insulien vlakke dieselfde was (12.42 ± 5.06 j.lIU/ml en 12.87 ± 1.02 j.lIU/ml), was serum glukose vlakke van die HKD diere hoër as die van die ooreenstemmende kontroles (9.2 ± 0.3 mmoiii en 7.8 ± 0.3 mmoiii (p<0.05)). Plasma lipied profiele (HOL cholesterol, plasma cholesterol en trigliseriede) was abnormaal in die HKD diere. Plasma TAG vlakke in die HKD diere was beduidend hoër as die van die kontroles (0.664 ± 0.062 mmoiii en 0.503 ± 0.043 (p<0.05)), terwyl plasma cholesterol vlakke (1.794 ± 0.058 mmoiii en 2.082 ± 0.062 mmoiii (p<0.05)) en HOL cholesterol vlakke beduidend laer was (1.207 ± 0.031 mmoiii en 1.451 ± 0.050 mmoiii (p<0.05)). Miokardiale meganiese funksie was dieselfde vir beide groepe voor isgemie, maar die persentasie aorta omset herstel tydens herperfusie was laer in die HKD diere in vergelyking met die van kontrole diere (47.86 ±. 7.87% en 66.67 ± 3.76% (p<0.05)). Serum TNFa vlakke van die HKD diere was beduidend hoër as die van kontrole diere (51.04 ± 5.14 AU en 31.46 ± 3.72 AU (p<0.05)), maar miokardiale TNFa vlakke was laer (312.0 ± 44.7 pglgram nat gewig en 571.4 ± 132.9 pglgram nat gewig (p<0.05)). Die vetweefsel TNFa vlakke was ook beduidend verhoog na 12 weke op "n hoë kalorie dieët wanneer dit vergelyk word met die van kontrole diere (4.4 ± 0.4 pglgram nat gewig en 2.5 ± 0.3 pglgram nat gewig respektiewelik (p<0.05)). Daar was geenbeduidende verskille in die miocardiale vlakke van sGMP in die HKD diere in vergelyking met die kontroles na 6, 9 en 12 weke. Gevolgtrekkings: 1) "n Hoë kalorie dieët het in dié studie vetsug geïnduseer en tot miokardiale hipertrofie gelei. 2) Daar was "n positiewe korrelasie tussen verhoogde vetweefsel en serum TNFa vlakke, en miokardiale hipertrofie. 3) Verhoogde serum TNFa vlakke het nie tot die aktivering van die miokardiale NO-sGMP pad in hierdie model gelei nie. 4) Die hipertrofiese harte het tydens herperfusie ná isgemie swakker as hulooreenstemmende kontroles gefunksioneer.
108

DDT as a malarial vector control method and its potential risks to human reproductive health and neonatal development

Siu, Ka-yan, Sky., 蕭加欣. January 2007 (has links)
published_or_final_version / Community Medicine / Master / Master of Public Health
109

Association between tea drinking and markers of rheumatoid arthritis: a cross sectional study of baseline datafrom the Guangzhou biobank cohort study

Cheng, Ping-yuen., 鄭秉源. January 2006 (has links)
published_or_final_version / Community Medicine / Master / Master of Public Health
110

Ventilation for controlling airborne infection in hospital environments

Qian, Hua, 錢華 January 2007 (has links)
published_or_final_version / abstract / Mechanical Engineering / Doctoral / Doctor of Philosophy

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