Firefighting is a very hazardous profession. Firefighters experience an injury rate that is three times higher than other physically demanding professions and the death rate in the fire service is also much higher compared to typical. Throughout the literature, data suggest the physical nature of firefighting contributes to the high incidence of injury and death among firefighters. As such, special interest groups and firefighting organizations advocate for firefighters to exercise and stay fit in order to safeguard their physical health. Yet, despite these efforts, firefighters still experience a very high incidence of back injuries and heart attacks which can lead to early retirement from disability or death. In the first aim of this dissertation, we examined the relationships between specific back fitness tests and history of back injuries in 113 firefighters in an effort to understand which fitness tests may aid in screening firefighters for risk of back injury. We found that a test of lumbar extension flexibility was associated with a higher incidence of back injuries among our sample (p<0.01). In the second aim of the study, we investigated whether perceived fitness was related to history of back injuries since firefighters’ perceptions of their fitness level may direct how they choose to perform job tasks that pose high risk for injury. Within the same sample of firefighters, we found that perceived fitness was not related to history of back injuries nor was the relationship between actual fitness and history of back injuries mediated by perceived fitness. However, perceived fitness correlated with scores on our back strength (r=0.28; p=0.003) and hamstring strength (r=0.21; p=0.03) tests. In the third aim of the dissertation, we sought to develop a treadmill walking protocol to screen firefighters for low aerobic capacity which is a major risk factor for heart attack. Thirty-eight male firefighters wore a vest weighing 20% of their body weight and performed a walking VO2max test in which the treadmill grade increased by 1% each minute. The predicted VO2max from this walking test was very accurate; within a standard error of the estimate of 3.2 ml/kg/min. This new (Moore) protocol requires only a standard treadmill and is more job specific than a running test. In conclusion, more research needs to be conducted to understand how firefighters’ perceived fitness directs their behaviors when performing job tasks and how high levels of fitness can protect against back injuries and heart attacks in firefighters. This dissertation has contributed to the development of screening protocols to aid in preventing these adverse events. / Graduation date: 2013

M.Tech. Business Administration. Business School. / The purpose of this study is to investigate the internal behavioural barriers to the implementation of hazard analysis and critical control point (HACCP). This investigation aims to assist the hospitality industry in implementing best practice in food hygiene to maximise public food safety and profitability. It also aims to investigate and possibly generate creative initiatives to control and monitor the long-term implementation of hazard analysis and critical control point principles in the sector so as to render it competitive on an international level.

Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-08-05T15:07:47Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) 20160404 Tese final Duarte catalogada formato digital.pdf: 4026733 bytes, checksum: d6ac5259ffcea51116ee53e1ba8c164a (MD5) / Made available in DSpace on 2016-08-05T15:07:47Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) 20160404 Tese final Duarte catalogada formato digital.pdf: 4026733 bytes, checksum: d6ac5259ffcea51116ee53e1ba8c164a (MD5) Previous issue date: 2016-03-18 / CNPq / The environment is a complex system where human, ecological environment (e.g., plants, animals, microbes), materials (eg, pollutants, medical), and meteorological/oceanographic conditions interact. The human impact has potential to cause significant damage to the ecological environment (e.g., potential oil spills on the coast cause risk to coastal ecosystems, tuna industrial fishing cause risk to sharks that are bycaught). Similarly, the human impact may turn against the human itself by favoring the growth of populations of unwanted species (e.g., poor sanitation favors the growth of microbial populations that cause risk of an excessive proportion of sick humans). Therefore, it has been demanded an efficient method of quantifying the risks in systems where plant, animals or microbes populations are involved in order to give support to risk management in environmental issues, fisheries management and public health. First, this paper proposes a methodology capable of quantifying ecological risks (i.e., likelihood of adverse effects on the ecosystem, in the long term, due to exposure to stressors such as chemical, fishing, etc.) or microbial risks (i.e., likelihood of adverse effects in humans, in the long term, due to exposure to microbial pathogens). It uses population modeling to simulate future changes in populations of ecologically important species (e.g., fish, corals, sharks), or undesirable (e.g., parasites), under conditional scenarios simulating the influence humans impacting and/or managing the risks. The risk is calculated in terms of probability of extinction or decline, explosion or growth of these populations over time. Second, the methodology is applied to four case studies in Brazil. Each of them have their specific conclusions, as follows. (1) Ecological Risk Assessment caused by potential maritime accidents in the transportation of oil to the port of Suape. Conclusion: low but significant ecological risk. (2) Ecological Risk Assessment caused by potential maritime accidents in the passage of oil tankers nearby Fernando de Noronha. Conclusion: negligible ecological risk, although a more detailed analysis is required due to limited data. (3) Microbial Risk Assessment to Porto de Galinhas community inherent to sanitation and medical treatment program. Conclusion: high microbial risk, the current sanitation level is not enough to contain the spread of schistosomiasis disease, and periodic treatment of patients is not efficient to reduce risks significantly. (4) Ecological Risk Assessment of tuna industrial fishing in Brazilian waters. Conclusion: industrial tuna fishing does not cause significant risks to the population of Mako sharks in the South Atlantic Ocean. In each case study, several conditional scenarios were simulated for the next 100 years, including adverse scenarios and scenarios with risk control measures. Thus, it was possible to quantify the added risk caused by each adverse condition as well as the reduced risk caused by each control measure. In this way, the manager has objective information to prioritize scenarios and evaluate the cost-effectiveness of control measures. The general conclusion of this work is that the proposed methodology has proven to be practicable, useful and efficient. / O meio-ambiente é um sistema complexo onde interagem humanos, meio ecológico (e.g., plantas, animais, micróbios), materiais (e.g., poluentes, medicinais) e condições meteorológicas/oceanográficas. O impacto humano tem potencial para causar danos significativos ao meio ecológico (e.g., potenciais vazamentos de petróleo na costa causam risco ao ecossistema costeiro, pesca industrial de atum causa risco aos tubarões que são pescados por acidente). Similarmente, o impacto humano pode se voltar contra o próprio humano ao favorecer o crescimento de populações de espécies indesejáveis (e.g., saneamento básico precário favorece o crescimento de populações de micróbios que causam risco de haver uma excessiva parcela de humanos doentes). Portanto, tem sido demandado um método eficiente de quantificar os riscos inerentes a sistemas onde populações de plantas, animais ou micróbios estejam envolvidas, de forma a dar suporte para o gerenciamento dos riscos em problemas de gestão ambiental, gestão pesqueira e saúde pública. Em primeiro lugar, este trabalho propõe uma metodologia capaz de quantificar riscos ecológicos (i.e., probabilidade de ocorrência de efeitos adversos no ecossistema, no longo prazo, devido à exposição a estressores como químicos, pesca, entre outros) ou microbianos (i.e., probabilidade de ocorrência de efeitos adversos em humanos, no longo prazo, devido à exposição a patógenos microbianos). Utilizase a modelagem populacional para simular futuras mudanças nas populações de espécies ecologicamente importantes (e.g., peixes, corais), ou indesejáveis (e.g., parasitas), quando condicionadas a cenários que simulam a influência do humano causando impacto e/ou gerindo os riscos. O risco é calculado em termos de probabilidade de extinção ou declínio, explosão ou crescimento, dessas populações ao longo do tempo. Em segundo lugar, aplica-se a metodologia para avaliar o risco inerente a quatro estudos de caso no Brasil. Cada um deles tem sua conclusão específica, como segue. (1) Análise de Risco Ecológico causado por potenciais acidentes marítimos no transporte de petróleo para o porto de Suape. Conclusão: baixo risco ecológico, porém significativo. (2) Análise de Risco Ecológico causado por potenciais acidentes marítimos na passagem de navios petroleiros ao largo de Fernando de Noronha. Conclusão: risco ecológico negligenciável, mas uma análise mais detalhada é necessária devido à escassez de dados. (3) Análise de Risco Microbiano à comunidade de Porto de Galinhas inerentes ao sistema de saneamento básico e programa de tratamento medicinal. Conclusão: alto risco microbiano, o nível de saneamento básico atual não é suficiente para conter a proliferação da doença esquistossomose, e o tratamento periódico de doentes não é eficiente para reduzir os riscos significativamente. (4) Análise de Risco Ecológico causado pela pesca industrial de atum em águas brasileiras. Conclusão: a pesca industrial de atuns não causa riscos significativos à população de tubarões Mako no oceano Atlântico Sul. Em cada estudo de caso, foram simulados diversos cenários condicionais para os próximos 100 anos, incluindo cenários adversos e cenários com medidas de controle dos riscos. Assim, foi possível quantificar a adição do risco causada por cada cenário adverso e a redução do risco causada por cada medida de controle. Desta forma, o gestor tem informação objetiva para priorizar cenários e avaliar o custo-benefício das medidas de controle. A principal conclusão deste trabalho é que a metodologia proposta provou-se ser praticável, útil e eficiente.

HIV risk assessment models use multiple risk factors to build composite index scores to evaluate population level HIV risk. In this report, four risk assessment models were applied to a dataset with demographic, biological, and behavioral risk factors from 927 individuals in high and low HIV burden zip code groups in metro Atlanta, GA. Predictive ability of the risk assessment models were evaluated by comparing their sensitivity and specificity, area under the ROC curve, and mean score difference between high-burden and low-burden zip code area. The results show that the proportion of study participants who scored high in the risk assessment method are significantly greater in high-HIV burden zip code area than in low-HIV burden zip code area in all four risk assessment models. The Clinical Decision Rule risk-scoring model showed the best predictive ability of HIV risk and Binary Risk Indicator model showed the best predictive ability in predicting the residence zip code area.

Polycyclic aromatic hydrocarbons (PAHs) are common soil contaminants due to their lipophilic nature which limits partitioning to water or air. Soil properties such as organic carbon can affect PAH release from soil, and thus affect PAH bioavailability of ingested soil. Risk assessment of PAHs in soil generally assumes equal bioavailability of PAHs ingested in soil compared to PAHs ingested in reference dose media, leading to environmental cleanup guidelines that are potentially too conservative. This research intended to use the juvenile swine model to assess PAH bioavailability from impacted soil to better inform bioavailability estimates for risk assessment. This was done by assessing PAH bioavailability from single and repeated exposure to PAHs in different spiked exposure media, assessing PAH bioavailability from soil collected from PAH impacted sites, and assessing biomarkers of exposure and effect following PAH exposure. The effect of exposure duration on bioavailability was assessed because people are usually chronically exposed to PAHs, rather than acutely exposed, as most bioavailability studies are performed, and chronic exposure may lead to increases in xenobiotic metabolizing enzymes and transporters which may affect bioavailability. This research found that exposure duration did not significantly affect anthracene and benzo[a]pyrene bioavailability (p>0.075), but exposure media did (p<0.004). These results suggest that exposure medium has a more important effect on bioavailability than exposure duration, and also bioavailability calculated from a single exposure is appropriate for use in risk assessment. Bioavailability from 24 naturally impacted soils was assessed to determine which soil characteristics had the greatest effect on PAH bioavailability. Area under the curve (AUC) measurements for benzo[a]pyrene (BaP) and anthracene in swine blood after oral exposure from a soil matrix for benzo[a]pyrene and anthracene in soils had s very poor relationship with soil concentrations in soils collected from impacted sites (r2<0.15), but a very strong relationship with soil concentrations from spiked artificial soils (r2<0.95). As spiked soils had much higher concentrations of PAH, these results suggest there is a point of departure in soil concentrations where internal exposure becomes linearly related to soil concentration. Point of departure modeling indicates that this point occurs at soil PAH concentrations greater than 1,900 mg kg-1. Thus, risk assessment can assume a constant exposure to PAHs at soil concentrations lower than the point of departure. Comparison of terminal rate constants from intravenous (IV) exposure to PAHs and oral exposure to PAHs in a soilmatrix suggest that flip-flop kinetics occur in swine, where absorption occurs at a slower rate than elimination. Flip-flop kinetics likely explains the lack of relationship between real world soil concentrations and area under the curve measurements as absorption is the rate limiting step of elimination. Biomarkers of exposure and effect were assessed in swine liver and ileum tissue, as well as blood following single and subchronic exposure to PAHs to determine if relationships could be drawn between exposure magnitude and duration and biomarker formation. Biomarkers included cytochrome P450 (P450) 1A1, 1A2, and 1B1 expression and activity as biomarkers of exposure and DNA adducts, carbonylated proteins, and micronucleated reticulocytes as biomarkers of effect. Biomarkers of exposure were not affected by exposure magnitude or duration, indicating that they would serve best as exposure markers rather than indicators of bioavailability or other effects. However, DNA adduct and protein carbonyl formation was significantly affected by exposure duration (p<0.045), but micronuclei formation was not. The micronuclei results suggest the liver was effective at clearing PAHs to non-toxic metabolites at the study doses, while tissue biomarkers of effect may correlate more effectively with exposure iv length and magnitude of dose. This work indicates that PAH bioavailability from soil is lower than 100%, but additional work needs to be done to determine soil characteristics that affect bioavailability and to determine a bioavailability value relative to reference material.

Thesis (MBA) -- Stellenbosch University, 2007. / ENGLISH ABSTRACT: Hedge funds are amongst the fastest growing types of investment funds, both in tenns of worldwide assets under management, as well as the number of private and institutional investors. More recently, analysts and investors focussed their attention on accurately estimating the inherent risks of hedge funds (e.g, Brooks & Kat, 2001; Fung & Hsieh, 2004). Past research suggests that the traditional approach of assessing the risks of investment funds through mean-variance analysis can lead to severe underestimation of left-hand-tail risks for hedge funds (Amenc, Malaise, Martellini & Vaissie, 2004; Favre & Galeano, 2002; Fung & Hsieh, 1999). This phenomenon is mainly attributab le to the non-normal distribution of monthly hedge fund returns around the mean. In addition, it has been found that skewed return distribution with high excess kurtosis has substantial impact on the rel iability of beta as a measure of systemic risk in hedge funds (Chan, Getmansky, Haas & Lo, 2005). Other problems when estimating hedge fund risks arise from serial correlation of time series (Getmansky, Lo & Makarov, 2003), managerial and survivorship bias (Amin & Kat, 2001 ), as well as spurious bias when estimating performance from economic time series (Fung & Hsieh, 2000). The following thesis provides statistical evidence of the limitations of traditional risk measures when applied to hedge fund investments. It also includes advice on how to improve the significance of the aforementioned risk measures. In the course of the mean-variance analysis, the applicability and reliability of Value at Risk as a risk measurement tool for hedge funds is explored. Furthennore, the reliability and accuracy of different univariate and multivariate regression models is tested. In the final chapter emphasis is placed on the possibilities of predicting the inherent risks of single funds from hedge fund style index performance. This should provide investors and analysts with an introductory framework for the appropriate risk assessment of hedge funds, considering the unique structure and dynamics of these alternative investment funds. / AFRIKAANSE OPSOMMING: Skansfondse tel onder die vinnigste groeiende tipes beleggingsfondse in terme van sowel wereldwye bates onder bestuur as die aantal private en institusionele beleggers. OnJangs het analiste en beleggers hulle aandag daarop begin toespits om die inherente risiko's verbonde aan skansfondse akkuraat te bereken (Brooks & Kat. 2001; Fung & Hsieh, 2004). Vroeere navorsing het daarop gedui dat die tradisioncle benadering om die risiko's verbonde aan beleggingsfondse deur gemiddeldevariansie-analise te takseer, daartoe kan lei dat linkerkantse-eindrisiko's verbonde aan skansfondse emstig onderskat word (Fung & Hsieh, 1999; Favre & Galeano, 2002; Amenc. Malaise, Martellini & Vaissie, 2004). Hierdie verskynsel is hoofsaaklik toe te skryf aan die abnonnale verspreiding van maandeliksc skansfondsopbrengste rondom die gemiddelde. Boonop is bevind dat skewe verdeling met hoe kurtose-oorskryding aansienlik inslaan op die betroubaarheid van beta as 'n meting van sistemiese risiko by skansfondse (Chan. Getmansky. Haas & Lo, 2005). Ander probleme by die raming van skansfondsrisiko's spruit uit tydreekskorrelasie (Getmansky, Lo & Markov, 2003), bestuurs- en oorlewingsydigheid (Amin & Kat, 2002) en vals sydigheid by die beraming van prestasie uil die ekonomiese tydsreeks (Fung & Hsieh, 2000). Hierdie tesis gaan statistiese bewyse lewer van die tradisioncle risikometings se beperkings wanneer dit op skansfondsbeleggings toegepas word. Verder sal daar raad gegee word oor hoe om die beduidendheid van die genoemde risikometings te verbeter. In die loop van die gemiddeldevariansie-analise sal die toepasbaarheid en betroubaarheid van die Waarde onder Risiko as 'n risikometing vir skansfondse ondersoek word. Voorts sal die betroubaarheid en akkuraatheid van verskillende ecnvariaat- en meervariaatregressiemodelle getoets word. In die laaste hoofstuk val die klem op die moontlikheid om die inherente risiko's van enkelfondse aan die hand van 'n skansfondstipe-indeksprestasie te voorspel. Wat hier volg, behoort beJeggers en analistc van 'n inleidende raamwerk vir die toepaslike risikotaksering van skansfondse - met inagneming van die unieke struktuur en dinamika van hierdie altcmatiewe beleggingsfondse - te voorsien.

published_or_final_version / abstract / Environmental Management / Master / Master of Science in Environmental Management

published_or_final_version / Applied Geosciences / Master / Master of Science

published_or_final_version / Applied Geosciences / Master / Master of Science

<p>The old water system in Sala, formerly belonging to thesilver mine, is analysed with regard to dam safety focusing onthe hydrological aspects. The hydrological safety of the riskclass I dams in the area, built in the 16th century, is notconsidered adequate according to the Swedish guidelines fordesign flood determination. A review is made of internationalprinciples for design flood determination. The overview showsthat there is no common principle used internationally whendealing with design flood for dams. In some countries there isan ambition to implement risk assessment for evaluation ofhydrological safety. However, at present Australia is the onlycountry that has fully integrated risk assessment in theirdesign flood guidelines. A risk assessment of the water systemin Sala shows that neither increasing the spillway capacity norimplementing flood mitigation measures in the watershed haveany significant effect on dam safety in the area. Nothingindicates that watersheds with a high presence of mires, likein the Sala case, should be particularly well suited forimplementing flood mitigation in the watershed as a dam safetymeasure. In order to safely handle the design flood in Sala andavoid dam failure due to overtopping the flood needs to bediverted from the water system.</p><p><b>Key words:</b>dam safety; design flood; flood mitigation;hydrological; risk assessment</p>