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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.
141

Site Assessment and Remediation Feasibility Study of a Petroleum Hydrocarbons Contaminated Site

Wu, Long-chem 07 September 2004 (has links)
This study presents detailed procedures for site assessment, remedial system design, and optimization of the remedial action operation (RAO) for the petroleum-hydrocarbons contaminated sites. In this work, a petroleum-hydrocarbons contaminated site located in southern Taiwan was selected. Contaminants of concerns (CoCs) from leaking underground storage tanks (USTs) and associated piping included mono-aromatics (e.g., benzene, toluene, ethyl-benzene, xylenes), naphthalene, and aliphatic hydrocarbons. The direct push (DP) technology was adopted for soil gas and soil samples collection. CoCs in the affected subsurface soils and the aquifers were determined by solid-phase micro-extraction/gas chromatography/mass spectrometry and several other analytic instruments. Site investigation via various tests was conducted to evaluate the geology, hydrogeology, bioactivity and free product availability. Based on results of specific site characterization, successful hydraulic containment and substantial recovery of observed free-phase petroleum product were achieved. During the process of field-scale remediation, a test cell which was equipped with a subset of monitoring points and numerous different function active wells (injection well, extraction well, monitoring well, soil gas monitoring probe, reference well and recovery well) was used for remedial system evaluation. A treatment train consisting of the source control treatment and in situ groundwater treatment technology was employed in this study. The former included a vertical containment barrier (i.e., slurry wall) and three pumping wells, whereas the latter included some passive remedial activities. Approximately 87% to 95% decline of the CoCs concentration was observed in those monitor wells after 135 days of operation. Results show that the spilled light non-aqueous phase liquids (LNAPLs) could be efficiently contained and removed using the treatment train system. The treatment train application could be successfully used to reduce the concentrations of CoCs in groundwater to satisfactory levels. Benzene was found to be the only compound in groundwater violating the groundwater pollution control standard. The risk assessment process including hazard identification and exposure assessment was conducted to assess the risk impact of benzene on the human health. Using the methodology approved by ASTM and American Petroleum Institute (API), the baseline carcinogenic risk (9.0E-07) and risk-based groundwater screening level for benzene (0.660 mg/L) were determined. The BIOPLUME III model was also applied to simulate the transport and fate of benzene in site groundwater. Results from this study indicate that site assessment coupled with the treatment train could be used to reduce the concentrations of CoCs in groundwater and soil to satisfactory levels efficiently and effectively.
142

Health risk communication : reporting of avian influenza in New Zealand newspapers 2002-2008 : a thesis submitted in fulfilment of the requirements for the degree of Master of Arts in Sociology, School of Social and Political Sciences, University of Canterbury /

Mackie, Brenda. January 2009 (has links)
Thesis (M.A.)--University of Canterbury, 2009. / Typescript (photocopy). Includes bibliographical references (leaves 146-158). Also available via the World Wide Web.
143

Validation of a risk assessment model to quantify the occurance of work related musculoskeletal disorders

Brandon, Katie. January 2002 (has links)
Thesis (M.S.) -- Mississippi State University. Department of Industrial Engineering. / Title from title screen. Includes bibliographical references.
144

Lessons learned through the analysis of public responses towards the release of governmental information during the SARS epidemic in HongKong

盧偉明, Lo, Brian L. January 2012 (has links)
The risk perception as presented by the media is important because it is usually through the media that the general population first receives information about an important event or crisis. The unique position of the media comes with a responsibility to provide a ‘communication bridge’ between the government and the general population. However the editorial choices determining the appropriateness of source, amount, and type of information conveyed to the public during a crisis is influenced by the contextual environment. The issue attention framework proposed by Downs was used to explore the possible links between the trajectory of a crisis and the media response may shed some light on the populations perception of risk during a crisis (the Hong Kong SARS epidemic in 2003) in which WiseNews was used to search the grey literature. The articles identified were classified into 4 categories: incidence, public health information, economy, and sensationalism by date of publication. These categories were then plotted on the Hong Kong hospital admissions and deaths epidemic curves. The study explored the potential link between key events during the Hong Kong SARS epidemic and the specific content of the medial publications. / published_or_final_version / Community Medicine / Master / Master of Public Health
145

Risques sanitaires et perception chez les agriculteurs utilisateurs de produits phytopharmaceutiques / Health risks and perception among farmers users of plant protection products

Boissonnot, Romain 08 December 2014 (has links)
ContexteDe nombreux facteurs influencent l’exposition des agriculteurs aux produits phytopharmaceutiques (PP) : facteurs techniques (matériel de pulvérisation, forme et type des PP employés), agronomiques (pression parasitaire, doses employées, type de culture) et humains. La perception d'un risque est un facteur déterminant du comportement humain face à celui-ci. La perception du risque phytosanitaire chez les agriculteurs et ses conséquences sur l'exposition aux substances actives des utilisateurs sont peu étudiées.ObjectifL’objectif de ce travail est d’évaluer comment la perception du risque influe sur les pratiques des agriculteurs. Il vise aussi à décrire et évaluer les déterminants de cette perception, et leurs impacts sur le risque sanitaire des utilisateurs de PP. Méthode.Des entretiens individuels sont menés pour évaluer la perception du risque auprès d’utilisateurs de PP. Des mesures et modélisations d’exposition complètent ces observations. Les mesures se focalisent sur les paramètres influencés par la perception du risque décrits lors des entretiens. Les résultats des mesures d’exposition sont comparés aux pratiques observées et servent à qualifier et quantifier l’impact de la perception sur le risque sanitaire.RésultatsCe travail montre que la perception des agriculteurs du risque liés aux PP est empirique et se base sur des critères tels que l'odeur, le type, la forme ou l'efficacité des produits pour estimer le risque. Les comportements des agriculteurs pour réduire leur exposition sont corrélés à leur perception des produits employés. L'utilisation des équipements de protection individuelle (EPI) est le marqueur le plus fort de la perception. Plus le risque est perçu comme important, plus l'utilisation d'EPI est élevée. Mais les pratiques de réduction du risque ne sont pas toujours efficaces pour réduire l'exposition. En effet, les mesures d'exposition réalisées montrent que les opérateurs, même utilisateurs d'EPI, n'ont pas conscience des phénomènes de contaminations indirectes (cabine des tracteurs, environnement de travail). Combinés à un mauvais usage fréquent des EPI (réutilisation d'EPI à usage unique, utilisation partielle ou inadaptée), ces défauts de perception jouent sur l'exposition aux PP.Les modélisations et mesure d’exposition en fonction des pratiques observées ont permis de quantifier les conséquences sanitaires de ces comportements. Il ressort que le risque sanitaire lors de l'utilisation des PP dans le cadre des bonnes pratiques est acceptable. Cependant ces bonnes pratique sont théoriques et les observations montrent que les opérateurs ont des comportements qui s'éloignent des bonnes pratiques et les exposent aux PP, mais ces comportements ne sont pas perçus comme tels. Le risque sanitaire associé aux pratiques est très individuel et difficilement généralisable. Cependant, ce travail exploratoire a permis de mettre à jour des profils de risque et de décrire les déterminants forts de la perception. La sensation de maîtrise du risque est le déterminant clef dans l'acceptation du risque par les agriculteurs. ConclusionCe travail montre que la perception du risque joue un rôle décisif dans l'exposition totale des agriculteurs aux PP. Le risque sanitaire est sensiblement dépendant de la perception du risque. Les politiques de prévention des risques doivent s'appuyer sur cet aspect afin d'adapter les messages et d'éduquer les opérateurs aux pratiques exposantes telles que la contamination indirecte ou le mauvais usage des EPI, aujourd'hui peu pris en compte par les utilisateurs de pesticides. / IntroductionMany factors influence the exposure of farmers to pesticides. Technical (spraying equipment, type of pesticides used), agronomic (type of crop, doses used, frequency) and human factors. The perception of risk is a determinant key of human behavior and how human faces to risk. Pest risk perception among farmers and the consequences of exposure to active substances of farmers have not been clearly studied.AimsThe objective of this study is to evaluate how risk perception affects farmers' practices. It also aims to describe and assess the determinants of this perception, and their impact on the health risk of pesticides users.Individual interviews are conducted to describe the perception of risk of pesticides' users. Measurements and modeling of exposure complement these observations. The measures focus on the parameters influenced by the perception of risk described in the interviews. The results of exposure measurements are compared to practices observed and used to qualify and quantify the impact of perception on health risk.ResultsThis work shows that farmers' perceptions of risk related to pesticides used is empirical and based on criteria such as smell, type, form or effectiveness of products to estimate the risk. Farmers' behavior to reduce exposure is correlated with their perception of the products used. The use of personal protective equipment (PPE) is the strongest marker of perception. The higher the risk perceived, the greater the use of PPE is high. But the practical risk reductions are not always effective in reducing exposure. Indeed, exposure measurements show that operators, even in users of PPE, are unaware of indirect contamination (cab tractors, work environment). Combined with frequent misuse of PPE (reuse of disposable PPE, partial or improper use), these defects perception are increase exposure to pesticides.Modeling and exposure’s measurement based on observed practices are used to quantify the health consequences of these behaviors. It appears that the health risk of pesticides is acceptable when used as recommended. However, recommended practices are theoretical and observations show that operators have behaviors that deviate from recommended practices depending on pesticides used. But these behaviors are not perceived as risky. The health risks associated with individual practice is very difficult to generalize. However, this work highlights profiles of risk and describes strong determinants of perception. The risk-control feeling is the key determinant in risk acceptance by farmers.ConclusionThis work shows that the perception of risk plays a decisive role in the exposure to pesticide of farmers. The health risk is substantially dependent on the perception of risk. The risk prevention policies must support this risk perception to adapt messages and educate the operators to not adapted practices such as indirect contamination or improper use of PPE, few considered by some pesticides users.
146

An evaluation of communication strategies used in the voluntary counselling and testing (vct) campaign at the University of Durban- Westville.

Tesfu, Tesfagabir Berhe. January 2003 (has links)
The present project evaluates and examines a communication campaign carried out at the University of Durban-Westville (UDW) in 2003, which publicized the introduction of a HIV/AIDS Voluntary Counselling and Testing (VCT) facility on campus. Drawing on theories 'of entertainment education (EE) and behaviour change, the campaign's effectiveness is analysed in relation to (1) audience reception; (2) take-up of the service promoted; and (3) visibility and penetration of the media employed. The thesis is that the message in campaigns of this nature benefits from avoiding claims of bringing about behaviour change by the mere fact of commurlication or information transfer. Instead, it is proposed that anti-H1V behaviour-change messages focus on urging audiences to act in presenting for VCT, because the ongoing counselling of VCT is a proper communicative forum for such changes. In conclusion, the present campaign's shortcomings are noted, and considered in the context of how to address these in relation to the opportunities offered by the merger ofUDW with the University of Natal from 2004. / Thesis (M.A.)-University of Natal,Durban,2003.
147

Conditions associated with levels of allergens and fungal aerosols in selected homes of selected primary school children in Durban.

Jafta, Nkosana. January 2007 (has links)
This indoor environment study formed part of the South Durban Health Study (SDHS) that investigated the health effects of exposure to ambient air pollution. Homes of children from seven communities corresponding schools were recruited to participate. This study was designed to determine characteristics in the homes that are associated with higher or lower levels of allergens and fungal aerosols. Homes were inspected using a field tested walkthrough checklist to collect data on home characteristics associated to adverse health effects. The characteristics include dampness, visible mould, type of flooring, type of bedding, type of heating systems, and building type and age. Dust samples for allergen analysis were collected from the bedding and the floor of the sleep area used by the children. Air samples from all rooms in the house were collected on malt extract agar, the media used for identifying and quantifying airborne fungal aerosols. More than 70% of the homes were single units standing on their own, 20% were attached houses (flats or apartments) and the rest (10%) were informal houses. Construction material of the homes comprised of bricks (93%), wood (5%) and other material (2%) such as corrugated iron of which 94% were formally constructed. Dampness signs were observed in 51% of the homes and visible mould growth 13% of them. In all them, at least one characteristic that is hypothetically associated to elevated house dust mite allergens was found. Levels of mould (Asp f 1) allergen and house dust mite (Der p 1 and Der f 1) allergen were comparable to levels found in other parts of the world. Asp f 1 allergen levels ranged between 0.32-1.379g/g and Der p 1 and Der f 1 allergen levels ranged from undetectable to 49.61 and from undetectable to 39.319g/g of dust respectively. Some home characteristics from walkthrough checklist were associated with Asp f 1, Der p1 and Der f 1 allergen levels when simple regression analysis was performed. Asp f 1 was significantly associated with single family home [OR= 0.004 (95%CI 0.004–0.35)] and polyester filled pillows [OR= 0.07 (95%CI 0.01– 0.61)] in logistic regression models. Der p 1 allergen was associated with observed extent of roof dampness [OR= 0.33 (95%CI 0.13–0.81)]. Fungal aerosol mixture consisted of Cladosporium spp. as the predominant genus together with other genera such as Aspergillus, Penicillium and Fusarium were, to a lesser extent, identified in the samples from the homes. Mean concentration of total indoor fungal aerosol of indoor and outdoor were 1108 CFU/m3 and 1298 CFU/m3 respectively. Individual genera of fungi in the childrens sleep area had mean levels of 783 CFU/ m3, 30CFU/ m3, 64CFU/ m3, 48CFU/ m3 and 43 CFU m3 for Cladosporium spp., Aspergillus spp., Penicillium, spp., Fusarium spp. and Rhizopus spp. respectively. Simple regression showed some conditions in the homes to be predictors of higher levels of total fungal aerosols. In a linear regression models, total outdoor fungal levels were a protective effect on total indoor fungal levels [C= 0.542 (95%CI 0.437–0.647)] whilst homes with hard floors had about 25 CFU/m3 [C= 5.235 (95%CI 0.557–9.913)] in the homes were significantly associated. This study showed the need to adapt observational instrument/ checklist/ questionnaire to suit the environment or the study area of interest. As other studies and findings indicated, the best way to assess exposure to biological pollutants indoors needs a combination of two or more methods, i.e. direct and indirect methods. / Thesis (MMedSc-Occupational and Environmental Health)-University of KwaZulu-Natal, 2007.
148

Ambient sulphur dioxide (SO2) and particulate matter (PM10) concentrations measured in selected communities of north and south Durban.

January 2006 (has links)
The industrial basin in the south of Durban is an area of ongoing contention between the residents and major industries, regarding environment health issues especially poor air quality resulting from industrial air pollution. This region is a result of poor urban planning that began in the early 1960's which saw rapid industrialisation alongside expanding communities, which has now resulted in a major environmental dilemma for the city of Durban, eThekwini Municipality. Durban is seen as a key area of growth in South Africa: it has the busiest harbour on the continent; it is a regional hub of the chemical industry and a major motor and metal manufacturer centre; and Durban's population continues to grow at ~4% per annum, all of which are destined to have significant environmental impacts. As part of a large epidemiological study and health risk assessment in this industrial basin, particulate matter smaller than 10 microns (PM10) and sulphur dioxide (S02) were measured in seven community sites across Durban: four in the South, (Wentworth, Bluff, Merebank and Lamontville) and three in the north (Kwamashu, Newlands East and Newlands West). The south sites are located in an industrial basin near two petroleum refineries and a paper mill, while the north comparison sites are ~25 km North West from major industries in the Basin. 24 hour PMIO samples were collected gravimetrically every day during four, three-week intensive phases and thereafter every 6th day using high, medium and low volume samplers. S02 was monitored every 10 minutes with active continuous analysers (European monitor labs and API) according to internationally accepted methods. Rigorous quality assurance methods were followed for both pollutants. S02 followed a distinct spatial distribution where the mean difference in S02 concentrations between the southern and the northern region was 6.7 ppb, while for PMIO similar concentrations were found across all sites with the highest mean concentration at Ngazana in the north (59 Ilg/m3) > Assegai in the south (~58 Ilg/m3) with all other sites ~ I to 10 Ilg/m3 less in mean concentration. S02 diurnal variations display two maxima from 5:00AM to 10:00AM being repeated in the latter part of the day from 20:00PM to 24:00PM. Seasonal pattern of PMIO and SOz to a lesser extent, display very similar mean variations for all sites - the highest levels seen in the colder months of May; June, July of 2004 and 2005. Weak to strong intersite correlations were found for SOz ranging from 0.16 to 0.22 among the south sites; 0.06 to 0.64 among the north sites, while PM10 ranged from 0.73 to 0.88 among the south sites and 0.86 to 0.91 among the north sites. A cross regional correlation of PMIO by sites displayed a moderate to strong correlation ranging from 0.73 to 0.88, while intrasite SOz with PMIO correlations displayed weak to moderate correlations from 0.35 to 0.53. Meteorological conditions wind speed, temperature, pressure and humidity differed across Durban. The difference in temperature and humidity between "summer" and "winter" was on average, approximately 7 °c and 10-15% respectively. These temperature and humidity patterns closely track the increase in SOz and PM10 during "winter" explaining the effects of winter inversions on pollutant levels. Also of interest is the variability of meteorological parameters between south and north Durban with the two regions being 35 km apart. Meteorological conditions impact differently on each pollutant e.g. rain is more likely to decrease PMIO concentrations than it would SOz In general relationships between pollutants and meteorological parameters differ on a site-bysite basis. For instance, wind direction at Assegai increases SOz levels whereas wind direction at Ngazana decreases SOz levels. Another independent variable that proved to be a consistent and important predictor for SOz and PM10 across most sites was the previous day's pollution events; this was a much stronger predictor for PM10 rather than SOz. These findings suggest that pollutants are not fully removed from the atmosphere during a 24 hour period and that the previous day's pollution levels will contribute to current levels, a finding that has important implication when implementing early warning pollution systems as envisaged for the Durban South Basin. / Thesis (MMed)-University of KwaZulu-Natal, 2006.
149

Indoor and outdoor environmental assessment of Durban block hostels : an internal evaluations on exposure measures and outcomes of self supported health and well-being in hostels.

Buthelezi, Sikhumbuzo Archibald. January 2007 (has links)
Hostel dwellers form a larger part of the urban population in South Africa (Ramphele, 1999). These hostels were initially created as temporal arrangement for African men moving from rural to urban areas seeking for employment. Due to housing shortage in urban areas they eventually became permanent residential accommodation. However, observations into the environmental conditions in these hostels have raised concerns about the health and well being of residents and neighbouring communities. The area of study was selected on the basis of the current depleted living conditions due to mismanagement of facilities provided by both the occupants and the hostel administrators. The study was a cross sectional descriptive study involving all three Durban Metropolitan block hostels. Assessing (i) the quality of block hostel environment (indoor and outdoor) through visual inspection (walkthrough), (ii) the exposure measures and outcomes (biophysical environment assessment) by means of questionnaire survey, air testing and microbial identification. Sixty three (63) hostel inventory were completed, followed by the administration of 450 questionnaires, and 646 surface and air samples were collected in the indoors of the selected hostel blocks including the control outdoor samples. The demographic profile of the hostel dwellers in the selected hostel blocks revealed that in the five bed type dormitories the habitable space per individual was 3 m 2 to 3.8 m2. Whilst in the ten bed type dormitories the habitable space per individual was 3.3 m 2 to 3.6 m2 . This was not even close to the World Health Organization suggested habitable space of 12 m2 (WHO, 2000) and was therefore regarded as overcrowding. Lack of access control in the hostels exacerbated by the socio-economic demands of the living environments, e.g. unemployment, was to blame for overcrowding. This overcrowding of the hostels was overloading the services, causing enormous number of blockages and bursts of wastewater pipes resulting in the system not functioning. This situation resulted in the accumulation of dampness in the indoor environment, and hence creating conditions favouring the growth of indoor mouldiness in the buildings. This was further supported by evidence that 47% of the occupants in the selected hostel blocks were experiencing respiratory symptoms and 53% experiencing non-respiratory symptoms. The most recorded respiratory symptoms were pulmonary tuberculosis (14.3%), chest tightness (12.2%), sore and dry throat (7%), sinus congestion (7%) symptoms. Whilst the most recorded non-respiratory symptoms were headache (11.5%), dry and itchy skin (11.5%), stomach upset (6.3%) and fatigue (3.6%). Forty five percent (45%) of the respondents were current smokers and 80% of them had a tendency of smoking indoors. The results of the surface and air samples indicated that the level of indoor mould growth in the selected hostel blocks was at 37, 24%. Surface moulds were at 58% and airborne spores were at 42%. Statistical analysis of data revealed a significant relationship between exposure factors and outcomes in the 5, 10 and 15-bed type dormitories. Incidence Risk Rate (IRR) and the p-value (p . 0.01) were used to determine relationships between exposure factors and outcomes. Certain factors were very much supportive in the development of selfreported symptoms in the selected hostel blocks of the three hostels under certain circumstances and these were the hygiene state of the building, leaking pipes, smoking habits and total mea and dg surface moulds. At all levels of the analysis the hygiene state of the building was very much supportive in the development of self-reported symptoms. Other exposure factors were not supportive at all, for example, structural defects, bed-types, different floor levels and participants' perception of overcrowding. A review process of the role of legislation in controlling the adverse health effects revealed that certain aspects of the legislation relating to building standards requirements, sanitation requirements, ventilation requirements, space and density requirements, and air quality standards requirements were violated. Therefore, the findings of the study recommended that a proper management plan must be developed to enhance living standards. This plan shall include a routine maintenance of the building structures, the development of a culture of self-care, as well as access control in the hostels. In addition to that where there are signs of visible moulds on walls and ceilings adequate control measures are highly recommended using commercially available measures in order to provide a healthy living environment. In conclusion is the adoption of a compliance policy towards legal requirements pertaining to building standards as defined in the National Building Regulations Standards Act (Act 103 of 1977). This study has showed that necessary iii steps need to be taken in South Africa in order to combat this problem. Further research need to be taken in order the inhabitable buildings to be better living environment improving the existing building structures. / Thesis (MMed.)-University of KwaZulu-Natal, Durban, 2007.
150

Exploring student nurses' risk perceptions of contracting tuberculosis during clinical placement in a selected KwaZulu-Natal college of nursing campus.

Cele, Winile Dorentce. January 2010 (has links)
The World Health Organization (WHO) declared Tuberculosis (TB) to be a global emergency (Baral, Karki & Newell, 2007). In KwaZulu-Natal 5704 TB cases were registered in 2009 (KwaZulu-Natal Uthukela Health District report, 2009). According to Mak, Mo, Cheung and Woo (2006) pulmonary tuberculosis (PTB) has the longest history compared to other two types of infectious diseases which are HIV/AIDS and Severe Acute Respiratory Syndrome (SARS). The purpose of this study was to explore student nurses’ risk perceptions of contracting tuberculosis (TB) during their clinical placement in a selected KwaZulu-Natal College of Nursing campus. The researcher used quantitative descriptive exploratory design. A questionnaire with closed and open ended questions was used to collect data from the respondents. Data was analysed using the Statistical Package for Social Sciences (SPSS) version 15. One hundred and thirty-two respondents participated in the study, 66 (50%) were first year students and 66 (50%) were second year students. The majority of the respondents were females n= 93 (70, 5%). The findings of the study indicated that student nurses perceived TB as a serious disease and they perceived themselves to be susceptible to contracting the disease during clinical placement. They also displayed good knowledge of preventive measures of risk perceptions, the highest mean score was 3, 79. The Fisher’s exact test was performed to establish a relationship between the variables, and it showed that there was a relationship between age and perceived barriers, p-value was 0,039. In conclusion, the respondents displayed relevant knowledge on TB preventive measures and positive perceptions of contracting TB, which will be the predisposing factors for behavioural change. / Thesis (M.N.)-University of KwaZulu-Natal, Durban, 2010.

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