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Análise da interação entre substâncias húmicas e xenobióticos através de estudos ecotoxicológicos: propostas para a geração de tecnologias de detoxificação aquática / Study of humic substances and xenobiotics interaction using ecotoxicological studies: aquatic detoxification technologies purposesBarbosa, Domingos Sávio 31 October 2008 (has links)
Este estudo teve como objetivo avaliar a interação entre substâncias húmicas e xenobióticos através de estudos ecotoxicológicos. O principal foco foi avaliar a resposta entre diferentes níveis tróficos em organismos aquáticos (fitoplanctônicos, zooplanctônicos, peixes e macroinvertebrados bentônicos) e terrestres (vegetais superiores, insetos e anelídeos) avaliando os efeitos diretos e indiretos das SH e de sua mistura com xenobióticos sobre os organismos. O reconhecido efeito das SH aumentarem ou reduzirem o efeito tóxico de algumas substâncias foi estudado. Os principais pontos para discussão são: a) SH podem reduzir ou estimular o crescimento algal (P. subcapitata); b) A presença de SH podem proteger os organismos contra efeitos tóxicos de metais, no entanto, a presença de Cd/Cu afeta negativamente o crescimento de C. xanthus. d) Em uma análise integrada de processos de remediação solo/água, a presença de SH afetou negativamente ou positivamente os efeitos tóxicos da atrazina em alguns organismos. A significância das SH como tecnologia é discutida. / This study focuses the interaction of humic substances and xenonbiotics, throw ecotixicological studies. The main point was quantify and qualify the ecotoxicological responses of several throphic levels of freshwater (algae, zooplankton, fishes and benthic organisms) and soil organisms (higth plants, insects and annelids) analyzing the direct and indirect effects of humic substances (HS) and their mixture on organisms. The recognized ability of HS on improve or reduce the toxic effect of same substances has been studied. The main points of discussion are: a) humic can be both reduce or stimulate the algal growth (P. subcapitata); b) The presence of HS can be protect aquatic organisms to negative effects of metals. However, the presence of mixture of Cd/Cu affect negatively the growth of C. xanthus; d) In a integrated analysis of remediation process in soil/water microcosm, the presence of HS displayed negative or positive effects on atrazine toxicity for some organisms. The value of humic technology was discussed.
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Diet of the Purple Swamphen in south Florida and invasion pathways of nonnative avian species in FloridaUnknown Date (has links)
The spread of nonnative invasive species has become the second greatest threat to global biodiversity, making management of invasive species a critical component of the conservation of biodiversity worldwide. Managers and conservation biologists often lack basic life history data, as well as quantitative and theoretical models to predict risk of invasion or other negative effects. I contribute information to both categories by providing life history information (diet and morphology) of the Purple Swamphen (Porphyrio porphyrio) and by characterizing the invasion pathways that nonnative avian species in Florida follow. I found Purple Swamphens are predominantly eating and selecting for Eleocharis cellulosa. Additionally, there is a large amount of variation in nonnative avian species’ propensity to colonize natural habitat and the time it takes to do so. Nine out of 15 species investigated colonized natural habitat and the time it took them to do so ranged from 8 to 41 years. It is through a combination of various techniques that ecologists will begin to fully understand the importance of studying nonnative species as well as reducing the impact that nonnatives have on native ecosystems. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2015 / FAU Electronic Theses and Dissertations Collection
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An educational tobacco intervention: impact of the Health Belief Model on college studentsUnknown Date (has links)
The purpose of this study was to determine whether an educational tobacco intervention impacted college students' perceptions relative to tobacco, self-efficacy, and perceived stress levels. The Health Belief Model (HBM) provided a theoretical framework to distinguish differences relative to tobacco between groups. Both the control (N=155) and intervention (N=184) group consisted of a convenience sample of students from a 2000-level health course. A pre- and post-test questionnaire was administered to both groups which included questions regarding demographics, tobacco use, HBM, self-efficacy, and perceived stress. Data analysis included frequency counts, confirmatory factor analysis, Cronbach's alpha, and two-way ANOVA. Two-way ANOVA results indicated statistically significant differences for the Health Belief Model questions (p=0.002) and self-efficacy items (p=0.03). No statistical significance was found regarding perceived stress. These findings provide evidence an educational tobacco intervention administered at the college level can have a significant impact on students. / by Kelley E. Rhoads. / Thesis (M.S.)--Florida Atlantic University, 2012. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2012. Mode of access: World Wide Web.
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Die gehalte van ondersoeke en die institusionele oordra van data oor aanmeldbare voedselvergiftigingsuitbrakeMalherbe, WF January 1997 (has links)
Thesis (MTech(Environmental Health)--Cape Technikon, Cape Town,1997 / The study project researched the quality of the investigations
and the institutional transfer of data regarding notifiable food
poisoning outbreaks reflected in "the study region", that is to
say North-, East- and Western Cape Provinces.
In comparing the data of the central-, provincial- and local
governments' total notifiable food poisoning outbreaks
notifications for specific local areas, problems relating to
incomplete and poor data, poorly completed reports and ignorance
of health workers re notifiable medical conditions were
identified.
Various conclusions and recommendations were made for "the
purpose of future improvements.
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An evaluation of flood risk communication efforts based upon the values judgements of the inhabitanats of a selection of informal settlements in the Cape Town municipal areaTigere, Diana January 2013 (has links)
Proposal submitted in partial fulfilment for the award of MTech in Environmental Management / It is widely believed that experts often have a more rational approach towards risks. This is because they are known to use algorithms, formal logic, risk assessments and normative rules to make decisions about risks. The central tenet of this research is that communication based on an understanding of how people conceptualise and evaluate risk communication efforts is critical for translating risk management knowledge into effective risk practices necessary for value generation in flood risk mitigation. Rational decisionEmaking requires both analytic and intuitive systems to operate on a parallel level. Therefore, this research proposes a Flood Risk Communication Model that takes cognisance of lay perceptions. The model emphasises on how risk communication efforts are evaluated by the lay using a combination of descriptive psychological and social construction theories. In particular, the prospect theory, heuristics and biases, cultural theory and trust theory are used to provide explanatory sketches on how flood risk communication efforts are perceived in highly vulnerable environmental contexts such as informal settlements. The challenge in this research however, lies in verifying the model empirically. The associative group analysis technique will be used to generate empirical data from a case study population. Two basic analytic methods will be employed to measure psychological dispositions of respondents. Firstly, word associations are scored and weighted based on frequency of occurrence to generate a dominance score. The higher the dominance score, the greater the interpretation and the more meaningful the theme is for that particular group. Secondly, the different theories of the model are factored into a questionnaire to measure priorities. All the responses are then compared to the proposed model and also used to evaluate actual lay perceptions and feelings towards the current risk communication interventions. The results showed a high level of consistency with the FRCM and hence with the descriptive psychological models of Kahneman and Tversky. However, we conclude that what is has been proposed to be biases are intuitive tendencies to adapt and make sustainable decisions in the face of applicable contextual influences. Thus, these contextual hierarchies determine the reference point and status quo of the recipient in decision making. Therefore, these influences and hierarchies need to be factored in the designing of a risk communication.
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Avaliação de risco ambiental e o processo de licenciamento : o caso do gasoduto de distribuição gás brasiliano trecho São Carlos - Porto Ferreira / Risk assessment and the process of environmental licensing : the case study of the natural gas pipeline between Sao Carlos and Porto FerreiraKirchhoff, Denis 02 June 2004 (has links)
O Licenciamento Ambiental é instrumento que se mostra com estreita ligação com processos de avaliação de impacto ambiental, e somente deve ser concedido após a certeza da conciliação entre a atividade e a qualidade ambiental. No Estado de São Paulo é usado o Relatório Ambiental Preliminar (RAP) como forma de se analisar a viabilidade ambiental de empreendimentos. Concluiu-se que o mesmo não serve como elemento no processo de licenciamento de gasodutos, pois não exige a necessidade de estudo de alternativas locacionais, e em sendo assim, seu uso não garante que a atividade analisada demonstre viabilidade ambiental, função fundamental de qualquer Estudo de Impacto Ambiental. O estudo de viabilidade ambiental necessita instrumentos que atribuam confiabilidade ao processo decisório e a Avaliação de Risco Ambiental (ARA) é uma ferramenta importantíssima, pois complementa a avaliação sobre a viabilidade ambiental do empreendimento, e se mostra útil para o Licenciamento Ambiental de atividades. Dessa forma, o principal motivo de escolha desta ferramenta decorre do fato de seu uso servir como instrumento para tomadas de decisões mais racionais e efetivas onde exista possibilidade de danos, o que a torna de suma importância na verificação da viabilidade ambiental de um empreendimento. A ARA foi aplicada ao transporte de gás natural por gasodutos, porque este combustível tem ganhado maior espaço na matriz energética do Brasil, com crescente tendência de expansão. Concluiu-se que a ARA deve ser usada desde o início do processo de licenciamento, já para a obtenção da primeira das licenças que é a LP. Com isso, os riscos são avaliados e usados como critério fundamental para o estudo de localização do traçado do gasoduto. Dessa maneira, os riscos de fatalidades associados a acidentes com gasodutos são reduzidos, garantindo mínimos riscos à população / Environmental Licensing is a tool showing great connection with the environmental impact assessment process, and should only be granted after the conciliation between activity and environmental quality is verified. The State of Sao Paulo has implemented the Preliminary Environmental Report (PER), which is used to evaluate the environmental suitability of activities. As it does not require consideration of all location (siting) and technology alternatives, the use of PER for licensing purposes does not assure under any circumstance that the analyzed activity presents environmental suitability, which is a fundamental role of any environmental impact study. Environmental suitability evaluation needs instruments to increase reliability to decision making, and Risk Assessment (RA) is a very important tool because it complements the analysis about the activity's environmental suitability, making it essential for the Environmental Licensing process. RA was applied to the conveying of natural gas through pipes because the Brazilian natural gas network has been expanding for the last few years. It was concluded that RA should be used from the beginning of the environmental licensing process, adopting associated risks as fundamental criteria for location study of the gas pipe route, which is an essential condition to define the environmental suitability of the proposed activity. This way, fatality risks posed by the gas lines are reduced, assuring minimal risks to the population/environment
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Avaliação quantitativa do risco de doença, causada por Vibrio arahaemolyticus, associado ao consumo de ostras (Crassostrea brasiliana) cruas cultivadas e comercializadas no Estado de São Paulo / Quantitative risk assessment of illness, caused by Vibrio parahaemolyticus, associated with the consumption of raw oysters (Crassostrea brasiliana) farmed and commercialized in the State of São PauloCosta Sobrinho, Paulo de Souza 03 August 2007 (has links)
Vibrio parahaemolyticus (Vp) é uma bactéria naturalmente presente em regiões estuarinas, sendo a principal causa de gastrenterite de origem bacteriana associada a pescados, principalmente ostras cruas. Nesta pesquisa, foi desenvolvida uma avaliação quantitativa de risco para avaliar a probabilidade de Vp causar doença após o consumo de ostra crua, produzida e comercializada no Estado de São Paulo. O estudo incluiu a identificação e caracterização do perigo, a avaliação da exposição e a caracterização do risco. Um modelo matemático foi desenvolvido. Este modelo leva em consideração o comportamento de Vp em ostras na cadeia produtiva, em cada estação do ano, além da relação entre a dose de Vp ingerida e a probabilidade de desenvolver a doença. A avaliação da exposição foi desenvolvida em três etapas: cultivo, pós-coleta e consumo. Na etapa de cultivo foram considerados os fatores que influenciam a prevalência e o número de Vp em ostras no momento da coleta. Na etapa pós-coleta, foram descritas as práticas da indústria e foram considerados os fatores associados ao processamento, transporte e manipulação. Já na etapa de consumo foram considerados os fatores como a quantidade de ostras consumidas por porção, o peso médio por ostra consumida e a população de Vp patogênico no momento do consumo. O resultado do modelo quantitativo da avaliação da exposição foi, então, integrado ao modelo dose-resposta, Beta-Poisson, para se obter uma estimativa do risco. Esta estimativa expressa o impacto da exposição humana a Vp, sobre a saúde pública, associada ao consumo de ostras. A simulação de Monte Carlo foi utilizada para avaliar o efeito da variabilidade e incerteza das variáveis do modelo sobre a estimativa do risco. O modelo prediz uma probabilidade de ocorrência de doença de 4,6x10-4, por porção de ostra, consumida ao longo do ano. As variáveis que possuem maior influência sobre o risco de ocorrência de doença são a população de Vp em ostras no cultivo, a temperatura de transporte das ostras até o varejo e a porcentagem de Vp patogênico em ostra, no momento do seu consumo. O modelo evidencia que uma das maneiras de reduzir o risco de ocorrência de doença seria intervir nas condições de transporte de ostras até o varejo por meio da sua refrigeração. Com o modelo é possível identificar fatores e simular cenários para avaliar o comportamento de V. parahaemolytícus como um perigo microbiológico, ao longo da cadeia produtiva de ostra até o momento do seu consumo. Também é possível avaliar o impacto de medidas de intervenção na cadeia produtiva. As suposições adotadas limitam a aplicabilidade do modelo. Portanto, é necessário que o modelo seja validado, particularmente com relação ao número de casos de doença causados por Vp, cujos dados de vigilância epidemiológica inexistem no Brasil. / Vibrio parahaemolyticus (Vp) is naturally present in estuarine regions and is the main cause of gastroenteritis associated with the consumption of bivalve molluscan shellfish, specially raw oysters. In this research, a quantitative risk assessment was developed to evaluate the probability of Vp causing disease after consumption of raw oyster, produced and commercialized in the state of Sao Paulo. The study included the identification and characterization of the hazard, exposure assessment and risk characterization. A mathematical model was developed. This model takes into account the behavior of Vp in oysters in the productive chain, for each season of the year, besides the relationship between the number of cells of Vp ingested and the probability of developing the disease. The exposure assessment was done in three steps: farming, after harvesting and consumption. At the farming step, the factors that influence the prevalence and the population of Vp at the time of harvesting were considered. At the after harvesting step, the factors associated with transportation, handling and processing were considered. At the consumption step, factors related to the amount of oysters and the average weight per oyster consumed and the density of pathogenic Vp at the time of consumption were considered. Then, the quantitative model of exposure assessment was integrated to the dose-response model, BetaPoisson, in order to obtain a risk estimate. This calculation expresses the impact of the human exposure to Vp associated with the consumption of oysters on public health. The Monte Carlo simulation was used to evaluate the effect of variability and uncertainty of variables of the model in the risk estimation. The model predicts a probability of occurrence of the disease of 4,6x10-4 per serving of oyster consumed during one year. The variables showing the greatest influence on the risk of occurrence of disease are the density of Vp in oyster in the farming step, the temperature during transportation of oysters to the retail market and the percentage of pathogenic Vp strains in oysters,\' at the moment of consumption. The model indicates that the use of refrigeration during transportation of oysters to retail could reduce the risk of disease. The model allows the identification of factors and the simulation of scenarios in order to evaluate the behavior of V. parahaemolyticus, as a microbiologícal hazard, in the productive chain of oyster to the consumption. It is also possible to evaluate the impact of intervention measures in the productive chain. The assumptions Iimit the application of the model. Therefore, it is necessary to validate the model, particularly in relation to the number of cases of dísease caused by V. parahaemolyticus of which the data on epidemiologic surveillance do not exist in Brazil.
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Análise de riscos para redução dos riscos de segurança em uma pedreira paulista. / Risk analysis to reduce safety risks in a São Paulo quarry.Leinfelder, Robson Rodrigues 22 September 2016 (has links)
Um programa de gerenciamento de riscos pode abordar simplesmente aspectos legais, previsto na Norma Regulamentadora nº 22 (BRASIL, 2016a), o que essencialmente exige a antecipação e identificação das condições perigosas, avaliação dos fatores de risco e registro dos dados levantados. Ou pode abordar a gestão dos riscos como parte inerente de seu negócio. A NBR ISO 31.000 (ABNT, 2009) recomenda um processo de gestão dos riscos, cuja identificação e classificação dos riscos, seja fundamentada por uma ferramenta de análise de riscos, adequada aos objetivos da organização e à natureza do risco que se quer analisar. Na presente dissertação foi utilizada a ferramenta de análise de riscos denominada Workplace Risk Assessment Control (WRAC). A WRAC é uma de análise de riscos semiquantitativa, desenvolvida para a indústria mineral, utilizada para mapear e classificar potenciais grandes riscos. No presente caso, a análise de riscos por meio da WRAC, visando reduzir os riscos de segurança em uma pedreira, integra o Programa de Gerenciamento de Riscos pretendido pela Pedreira, e tem como resultado prático a descrição de dezenove eventos indesejados, cuja classificação dos riscos de segurança resultou em quatro riscos toleráveis, oito riscos moderados, seis riscos significativos e um risco intolerável. O risco intolerável foi tratado e para cada risco moderado ou significativo foi estabelecido um plano de ação para tratamento dos riscos. A presente dissertação também apresenta três tabelas dos requisitos atendidos pela WRAC, em comparação com os requisitos do PGR da NR 22, da OSHAS 18.001 e da ABNT ISO 31.000. / A risk management program can treat of legal aspects of Regulatory Norm 22 (BRAZIL, 2016a), which essentially requires the anticipation and identification of hazardous conditions, assessment of risk factors and recording of the data collected. Or you can approach risk management as an inherent part of your business. ISO 31,000 (ABNT, 2009) recommends a process of risk management, whose identification and classification of risks is based on a risk analysis tool, appropriate to the objectives of the organization and the nature of the risk to be analyzed. In the present work was used the risk analysis tool called Workplace Risk Assessment Control (WRAC). WRAC is a semi-quantitative risk analysis, developed for the mineral industry, used to map and classify potential big risks. In the present case, the WRAC risk analysis, aimed at reducing the safety risks in a quarry, is part of the Risk Management Program intended by the quarry, and has as a practical result the description of nineteen unwanted events whose risk classification resulted in four tolerable risks, eight moderate risks, six significant risks and one intolerable risk. The intolerable risk was treated and for each moderate or significant risk was established an action plan for risk management. This dissertation also presents three tables of the requirements covered by WRAC, compared to the requirements of the PGR of NR 22, OSHAS 18.001 and ABNT ISO 31.000.
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Avaliação e gestão de riscos no controle da qualidade da água em redes de distribuição: estudo de caso / Risk management and assessment in the control of the quality of water in water distribution networks: a case studyMoreno, José 06 November 2009 (has links)
Esta pesquisa diz respeito à proposta de usar a avaliação e gestão de risco como instrumento para controle da qualidade da água para consumo humano e operação de redes de distribuição. Em 2004 a Organização Mundial da Saúde - OMS - apresentou uma proposta abrangente para controle da qualidade da água denominada PSA, na qual foi indicado um processo sistemático para identificação de perigos e procedimentos de gestão e controle de riscos. Segundo a OMS, o maior benefício em se desenvolver planos desta natureza é a sistematização, avaliação detalhada e a priorização de perigos - além de monitoramento operacional através de múltiplas barreiras de controle. Este trabalho tem como objetivo examinar a pertinência de utilizar a avaliação de risco na operação de redes de distribuição e no controle da qualidade da água para consumo humano. Para tanto foi estudado como os conceitos de avaliação e de gestão de risco podem ser especificamente aplicados em redes de distribuição de água. Este estudo possibilitou a identificação e caracterização de variáveis relevantes, as quais possibilitaram definir critérios e parâmetros, a partir dos quais foi possível elaborar método para a avaliação de risco microbiológico em redes de distribuição de água, baseado nos estudos de Godfrey et. al. (2002) e Tibatemwa (2003). A avaliação e a validação do instrumento proposto foram feitas por meio de estudo de caso desenvolvido no sistema de abastecimento de água de Itatinga, cidade de pequeno porte situada no interior do Estado de São Paulo. O método proposto propiciou conhecer em detalhes como é feita a gestão da rede de distribuição de água, indicou situações de perigo e, principalmente, permitiu quantificar os referidos riscos. A partir da compreensão dos riscos avaliados, através do modelo foi possível observar o efeito sinérgico de determinadas intervenções, tais como a substituição de tubulações com elevada pontuação de risco. O método proposto mostrou ser eficaz na identificação e caracterização dos riscos microbiológicos que envolvem a operação e o controle da qualidade da água em redes de distribuição. / The basis of this study corresponds to using risk management and evaluation as a tool for the control of the quality of water for human consumption and operation of water distribution networks. The need for developing and implementing a new way to control the quality of water intended for human consumption is identified and debated in this research due to evident limitations of the current \"Final Product Analysis\" in assuring reliability of the water distributed to the population. In 2004, the World Health Organization - WHO presented a comprehensive proposal for water quality control denominated WSP, Water Safety Plan, in which a systematic process for identifying hazards, management procedures, and risk control is indicated. According to WHO, the greatest benefits of developing plans such as this one are systematization, detailed evaluation, and prioritizing hazards, besides the operational monitoring through the multi-barrier control. The objective of this research is to discuss the use of risk evaluation in water distribution networks and in the control of the quality of water for human consumption. The application of risk management and evaluation concepts in water distribution networks was investigated. Therefore, it was possible to identify and characterize relevant variables, which enabled to define criteria and parameters in order to develop a methodology to evaluate the microbiological risk in water distribution networks based on the studies of Godfrey et al. (2004) and Tibatemwa (2003). The assessment and validation of the measures proposed were done through the analysis of a case study conducted in a water supply station in Itatinga, a small town located in the province of São Paulo state. The methodology proposed allowed a thorough investigation of the management of water distribution networks, identified risks, and mainly it made possible to quantify those risks. Having evaluated the risks, the synergistic effect of some operations, such as the substitution of pipes associated with high risk, could be observed using the model. The methodology proved efficient at identifying and characterizing the microbiological risks involved in the operation and control of water quality in water distribution networks.
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Shrinkage method for estimating optimal expected return of self-financing portfolio. / CUHK electronic theses & dissertations collectionJanuary 2011 (has links)
A new estimator for calculating the optimal expected return of a self-financing portfolio is proposed, by considering the joint impact of the sample mean vector and the sample covariance matrix. A shrinkage covariance matrix is designed to substitute the sample covariance matrix in the optimization procedure, which leads to an estimate of the optimal expected return smaller than the plug-in estimate. The new estimator is also applicable for both p < n and p ≥ n. Simulation studies are conducted for two empirical data sets. The simulation results show that the new estimator is superior to the previous methods. / By the seminal work of Markowitz in 1952, modern portfolio theory studies how to maximize the portfolio expected return for a given risk, or minimize the risk for a given expected return. Since these two issues are equivalent, this thesis only focuses on the study of the optimal expected return of a self-financing portfolio for a given risk. / Finally, under certain assumptions, we extend our research in the framework of random matrix theory. / The mean-variance portfolio optimization procedure requires two crucial inputs: the theoretical mean vector and the theoretical covariance matrix of the portfolio in one period. Since the traditional plug-in method using the sample mean vector and the sample covariance matrix of the historical data incurs substantial estimation errors, this thesis explores how the sample mean vector and the sample covariance matrix behave in the optimization procedure based on the idea of conditional expectation and finds that the effect of the sample mean vector is an additive process while the effect of the sample covariance matrix is a multiplicative process. / Liu, Yan. / Adviser: Ngai Hang Chan. / Source: Dissertation Abstracts International, Volume: 73-06, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 76-80). / 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.
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