Dissertations / Theses: 'Exposure index'

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Lundy, Erin. "The effect of assigning different index dates for control exposure measurement on odds ratio estimates." Thesis, McGill University, 2012. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=110733.

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In case-control studies it is reasonable to consider the exposure history of a case prior to disease onset. For the controls, it is necessary to define comparable periods of exposure opportunity. Motivated by data from a case-control study of the environmental risk factors for Multiple Sclerosis we propose a control-to-case matching algorithm that assigns pseudo ages at onset, index ages, to the controls. Based on a simulation study, we conclude that our index age algorithms yields a greater power than the default method of assigning a control's current age as their index age, especially for moderate effects. Furthermore, we present theoretical results that show that for binary and ordered categorical exposure variables using an inappropriate index age assignment method can obscure or even mask a true effect. The effect of the choice of index age assignment method on the inference on the odds ratio is highly data dependent. In contrast to the results of our simulation study, our analysis of the data from the motivating case-control study resulted in odds ratio and variance estimates that were very similar regardless of the choice of the method of assigning index ages.
Dans les études cas- témoins il est raisonnable de considérer que l'histoire de l'exposition d'un cas avant l'apparition de la maladie. Pour les témoins, il est nécessaire de définir des périodes de l'occasion d'exposition qui sont comparables. Motives par des données provenant d'une étude cas- témoins des facteurs de risque environnementaux pour la sclérose en plaques, nous proposons un cas- témoins algorithme de comparaison qui affecte des âges pseudo a l'apparition, âges d'index, aux témoins. Nous concluons, base sur une étude de simulation, que nos algorithme pour d'âges d'index donnent une plus grande puissance que la méthode défaut d'affecter l'âge actuel d'une témoins comme son âge d'index, particulièrement pour les effets modères. En plus, nous présentons des résultats théoriques qui montrent que pour des variables binaire et des variables ordinale, l'utilisation d'une méthode d'affectation inappropriée peut obscurcir ou mémé masquer un véritable effet. L'effet du choix de la méthode d'affectation sur l'inférence sur le rapport de cotes est très dépendant des données. En contraste avec le reste de notre étude de simulation, notre analyse des données de l' étude cas- témoins motivant a produit des estimations de le rapport de cotes et variance qui étaient très semblables quelque soit le choix de la méthode d'affectation des l'âges d'index.

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Crespo, Rodrigo Dinis. "Chromosomal damage in fish (Anguilla anguilla L.) induced by the fungicide Macozan® upon exposure and post-exposure periods." Master's thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/16837.

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Mestrado em Biologia Aplicada
Mancozan® is a dithiocarbamate fungicide used worldwide and its consumption has been increasing year after year. Due to its extensive use, their metabolites can be easily found in aquatic ecosystems around the world, representing thus a potential hazard to non-target organisms. Many studies performed with its active ingredient, mancozeb, have demonstrated its negative impact to fish. However, the toxic effects, and particularly the genotoxic potential of the commercial formulation Mancozan® are still poorly understood. Thus, and in order to improve the knowledge concerning this thematic, the present study aimed to evaluate the genotoxic potential of the fungicide Mancozan® to blood cells of the European eel (Anguilla anguilla) following a short-term (3 days) exposure to environmental realistic concentrations (2.8 and 28 μg.L-1). With the intuit of investigate the damage progression after the contamination source cessation, a post-exposure period (1, 7 and 14 days) was included, where fish were transferred to fungicide-free water. In order to evaluate the genetic damage, the ENA (erythrocytic nuclear abnormalities) assay was performed. Additionally, the frequency of immature erythrocytes (IE) was scored in order to provide indirect information on the erythrocyte catabolism and erythropoiesis rate. As a complement, the EMI (erythrocyte maturity index) was adopted in order to better discriminate the stage of erythrocytic immaturity. The obtained results demonstrated the potential of the highest concentration of Mancozan® to induce chromosomal damage, following a 3 days exposure, as well as a rapid recover in the post-exposure period. On the other hand, the lowest concentration of the commercial formulation was able to induce chromosomal damage only 14 days after the end of the exposure period, suggesting a progressive degradation and the collapse of eel erythrocytes defences. At the same time it was observed, through the IE assay and the calculation of the EMI, that the balance between the erythropoiesis, erythrocytes elimination and the cellular maturation rate was not affected by the exposure to the fungicide and consequently had no influence in the appearance of ENA. Globally, these results reinforce the idea concerning the pesticide risks to non-target organisms, highlighting the occurrence of a short-term genome-destabilizing in fish, as a result of occasional pesticide applications.
Mancozan® é um fungicida da família dos ditiocarbamatos amplamente utilizado em todo o mundo, tendo o seu consumo vindo a aumentar de ano para ano. Como consequência do seu uso intensivo, é possível encontrar os seus metabolitos nos ecossistemas aquáticos, representando assim um potencial perigo para organismos não-alvo. Vários estudos realizados com o seu princípio ativo, mancozeb, têm reportado um impacto negativo para peixes. Contudo, os potenciais efeitos tóxicos, e particularmente a genotoxicidade da formulação comercial Mancozan®, são ainda pouco conhecidos. Assim, e com o intuito de melhorar este conhecimento, o presente estudo pretendeu avaliar o potencial genotóxico da formulação comercial Mancozan® para células sanguíneas de enguia europeia (Anguilla anguilla), após uma exposição de curta duração (3 dias) a concentrações ambientalmente realistas (2.8 e 28 μg.L-1). No sentido de avaliar a progressão do dano após a cessação da exposição, foi incluído um período de pós-exposição (1, 7 e 14 dias) onde os peixes foram transferidos para água sem pesticida. O dano genético foi avaliado através do teste das ANE (anormalidades nucleares eritrocíticas). Em simultâneo, determinou-se a frequência de eritrócitos imaturos (EI), com o intuito de fornecer informação indirecta acerca do catabolismo dos eritrócitos e taxa de eritropoiese. No sentido de melhor discriminar o estado de maturidade dos eritrócitos, adoptou-se o índice de maturidade eritrocítica (IME). Os resultados deste estudo demonstraram o potencial genotóxico do Mancozan®, em particular para a concentração testada mais elevada, apresentando uma indução de dano cromossomal, após 3 dias de exposição, assim como uma rápida recuperação no período de pós-exposição. Por outro lado, a concentração mais baixa induziu dano cromossomal apenas 14 dias após o fim do período de exposição, já no período de pós-exposição, sugerindo uma degradação progressiva e o colapso das defesas eritrocíticas das enguias. Ao mesmo tempo foi observado, através da frequência de eritrócitos imaturos (EI) em conjunto com o IME, que o balanço entre a eritropoiese, a eliminação de eritrócitos e o ritmo de maturação celular não foram afetados pela exposição ao fungicida, não existindo uma influência no aparecimento de ANE. Deste modo, estes resultados reforçam a constatação dos perigos associados aos pesticidas para organismos não-alvo, dando um especial enfoque à ocorrência de uma destabilização de curto-termo do genoma dos peixes, como um efeito nefasto provocado pelas aplicações sazonais de pesticidas

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Gravel, Jonathan. "Prenatal Exposure to Maternal Cigarette Smoke and Offspring Body Mass Index: A Prospective Study of Québec Children." Thèse, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/20247.

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Concern is mounting over the increase in prevalence and severity of overweight and obesity in children worldwide. Intrauterine life has been identified as a critical period for the development of overweight or obesity and other related chronic diseases. Prenatal exposure to maternal cigarette smoke (PEMCS) has consistently emerged as an important risk factor for excess weight in the offspring and is a targetable behaviour for prevention strategies. This study examines first the relationship between PEMCS and overweight status of children at 10 years of age and second, whether PEMCS is associated with distinct longitudinal BMI trajectories. Analyses include multivariate and multinomial logistic regression and longitudinal group based modeling methods. PEMCS was found to be a significant risk factor for overweight in children independent of birth weight and catch-up growth. However, PEMCS was not associated with BMI trajectory membership. Our results lend support to the paradigm of in-utero excess weight prevention.

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Lömäng, Magnus. "Undersökning av exponeringsindex för bildplattesystem inför optimeringsarbete." Thesis, Linköping University, Department of Biomedical Engineering, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-2477.

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The county hospital of Dalarna has for the last couple of years carried through a process of digitalization. The result is that within the county it exists image plate systems from two different manufacturers. In an attempt to create a tool for dose optimization and dose surveillance the county of Dalarna would like to investigate if the exposure index from Agfa and Fuji is suitable as a dose indicator. An investigation of the exposure index, S, from Fuji has already been done. This thesis has been continuing the investigation by evaluating the stability of the exposure index, lgM, from Agfa. Simultaneously an observation if there is a simple relation between the exposure indicators from Agfa and Fuji has been performed. The result showed that the average of lgM, for a set of images from the same type of examination, is appropriate as a dose indicator to the image plate for that specific examination type and X-ray equipment. The usefulness is linked to the same tube voltage and Speed Class for a specific examination, and is to a certain degree restricted by the collimating. There is a relation between the exposure index from Agfa and Fuji, and there is in a simple way possible to transform S-values to lgM-values for comparison. The relation turned out to be examination specific.

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Olsson, Magnus. "Metod för dosoptimering av digitalt detektorsystem i klinisk drift." Thesis, Linköping University, Department of Biomedical Engineering, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-2471.

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The county of Dalarna is at present carrying through a process of digitalization where traditional x-ray film is being replaced with digital detectors. Earlier used methods for dose optimization turned out not being sufficient. This report presents a method to harmonize dose levels between x- ray sites equipped with Fujifilm imaging plate systems. An exposure index, S, related to the dose level of the examination is computed to every x-ray image. S turned out to be inversely proportional to the detector dose used at the examination. Detector dose is also the one simulated factor that doubtlessly affects S the most.There are however a lot of parameters, e.g difference between patients, that are not easily simulated even though they still have considerable affect. The method for harmonizing dose levels between x-ray sites are based on statistics of collected S-values for a kind of examination. The average of the collected S-values levels variations and is a more solid measure of the dose level for the examination. By means of this method the dose level of frontal images of the lungs at a site have been reduced by 30 per cent without endanger the diagnostic security.

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Lockey, Stephen. "The Association Between Childhood Traffic Exhaust Exposure and Asthma Differs Between Normal and Overweight Children." University of Cincinnati / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1352490277.

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Iheanacho, Ivory. "Can the USA National Weather Service Heat Index Substitute for Wet Bulb Globe Temperature for Heat Stress Exposure Assessment?" Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/5244.

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Heat stress occurs when the body cannot adequately cool itself due to the combined contributions of metabolic heat, environmental factors and clothing. Heat stress found in the workplace puts employees at risk of developing heat-related illnesses, disorders and could be fatal. The wet bulb globe temperature (WBGT) index is the current method used to assess environmental contributions to heat stress in an occupational setting. The purpose of this thesis was to explore whether the National Weather Service's Heat Index (HI) could substitute for the WBGT Index during occupational heat stress exposure assessment. The possibility of using the HI for heat stress exposure assessments was explored by first developing an occupational exposure limit based on the HI and then by comparing the HI to WBGT Index over a range of environments. Data from 10 selected studies were reviewed and categorized into two groups (Classic Data and Progressive Data) based on the method used to determine the upper limit of the prescriptive zone. WBGT and HI values were estimated from the environmental data provided in the 10 studies and the metabolic demands were also noted. These data were used to illustrate the relationship between environment (WBGT and HI) and metabolic rate. Next the relationship between HI and WBGT was compared over a range of environments consisting of combinations of air temperature and percent relative humidity as defined by the NWS's Heat Index Chart. Finally the effects of adding a high radiant heat load (Tg = Tdb+10 °C) to the relationship between WBGT and HI was explored. The HI occupational exposure limits were protective of the upper limit threshold points in a manner similar to WBGT. A greater spread in the Classic and Progressive upper limit data was observed above the occupational exposure limit when expressed as HI. High correlation was observed (R2 = 0.95) between the WBGT Index and HI over a range of environments, assuming no radiant heat. The incremental increase in HI due to high radiant heat indicated a strong dependency on the absolute value of HI, which makes using HI to predict WBGT in radiant heat environments problematic. Findings suggest the Heat Index could be used to assess heat stress exposures and to set occupational exposure limits for hot environments in the absence of high radiant heat.

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Jones, Antwan. "A Clean (Dollar) Bill of Health: Understanding Parental Socioeconomic Disparities in Child Health as Functions of Timing, Transitions and Exposure." Bowling Green State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1277149458.

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Allen, Whitney M. "The relationship between plasticity ratio and hydraulic conductivity for bentonite clay during exposure to synthetic landfill leachate." [Tampa, Fla.] : University of South Florida, 2005. http://purl.fcla.edu/fcla/etd/SFE0001393.

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Goudie, Anthony. "The effects of maternal prenatal insults on the BMI growth trajectory of children between the ages of 5-12 years." Thesis, Birmingham, Ala. : University of Alabama at Birmingham, 2008. https://www.mhsl.uab.edu/dt/2009r/goudie.pdf.

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Bastos, Jorge Tiago. "Road safety strategic analysis in Brazil: indicator and index research." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/18/18144/tde-08042015-103747/.

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The intense economic growth that Brazil has experienced in recent decades and its consequent explosive motorization process have resulted in an undesirable impact: the continuously increasing trend in traffic fatality numbers. This study presents a research on indicators and indexes with the objective of delivering both overall and disaggregated evidence about the road safety performance and targets in fatality reduction in Brazil at the state level taking the exposure into account. The intention is to support road safety strategic analysis in the country and to contribute to improve this critical scene. The methodological structure of this thesis consists of the following three main parts: (I) diagnosing the road safety situation at the state level using final outcome related information, in particular traffic fatality risk data; (II) setting a target number of traffic fatalities based on the relationship between the exposure level and the number of traffic fatalities in each state; and (III) suggesting domains for improvements based on the research of safety performance indicators representing three domains (road user, environment and vehicle) throughout the states. From a benchmarking point of view, we divided the Brazilian states into three separate clusters in order to provide more realistic state performance comparisons. After a data collection and indicators selection step, Data Envelopment Analysis (DEA) was the method used for executing the different steps, with the application of four different types of models specially developed for the identified research purposes. In addition, by means of bootstrapping the DEA scores we measured the sensitivity of the results to possible variations in the input data, for example concerning data quality and availability. As a result, we provided a road safety diagnosis per state as well as traffic fatality targets according to different perspectives: the entire group of road users (motorized and nonmotorized ones), motor vehicle occupants, and finally a disaggregated performance evaluation by running four separate DEA models (for motorcycle, car, truck and bus). Moreover, the SPI research including a hierarchy of 27 safety performance indicators expressed the states relative performance on the main road safety domains. Lastly, state profiles compiling all this information summarized the \"per state\" findings.
O intenso crescimento econômico que o Brasil tem experimentado nas últimas décadas e seu consequente explosivo processo de motorização resultaram em um impacto indesejado: a tendência contínua do aumento do número de mortes no trânsito. Este estudo apresenta uma pesquisa acerca de índices e indicadores com o objetivo de fornecer evidências gerais e desagregadas sobre o desempenho da segurança viária e metas de redução no número de mortes no Brasil no âmbito estadual, levando a exposição em consideração. A intenção é embasar uma análise estratégica da segurança viária no país e contribuir para melhorar este cenário crítico. A estrutura metodológica desta tese consiste das seguintes três partes principais: (I) diagnóstico da situação da segurança viária no nível estadual utilizando informações relacionadas ao resultado final, em particular dados de risco de morte no trânsito; (II) estabelecer uma meta para o número de mortes no trânsito para cada estado; e (III) sugerir domínios para melhorias baseado em pesquisa de indicadores de desempenho da segurança viária voltada a três domínios (usuário da via, ambiente e veículo). Sob a ótica do benchmarking, dividiram-se os estados brasileiros em três clusters para proporcionar comparações mais realistas dos desempenhos estaduais. Após uma etapa de coleta e seleção de indicadores, utilizou-se o método de Data Envelopment Analyis (DEA) para executar as diferentes etapas, com a aplicação de quatro tipos distintos de modelos especialmente desenvolvidos para os propósitos da pesquisa. Além disso, por meio de bootstrapping dos escores obtidos com a DEA, mediu-se a sensibilidade dos resultados a possíveis variações nos dados de entrada, no que diz respeito a, por exemplo, qualidade e disponibilidade dos dados. Como resultado, propicia-se, a partir de diferentes perspectivas, um diagnóstico da segurança viária por estado, assim como metas no número de mortes: para todo o grupo de usuários (motorizados e não-motorizados), ocupantes de veículos motorizados, e finalmente uma avaliação desagregada por meio de quatro modelos separados (para motocicletas, automóveis, caminhões e ônibus). Adicionalmente, a pesquisa de indicadores de desempenho da segurança considerando a hierarquia de 27 indicadores expressou os desempenhos relativos dos estados nos principais domínios da segurança viária. Por fim, perfis estaduais compilando todas estas informações resumem os resultados para os estados.

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Trippett, E. M. "Body Mass Index, avoidance and psychosocial factors : what moderates the impact of brief mirror exposure and other interventions on the body image of women?" Thesis, University of Sheffield, 2017. http://etheses.whiterose.ac.uk/18649/.

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Literature Review: This systematic review sought to determine whether interventions can reduce body dissatisfaction for adults, and whether body mass index (BMI) moderates the effectiveness of body dissatisfaction interventions. A search of two databases produced 14 studies, which generated 21 treatment groups. Where data were available, the relationships between effect size, quality score, publication date and treatment group mean BMI were calculated. A range of body dissatisfaction interventions were found to be effective, in particular those delivered in person, in groups, and using CBT components. There was a strong correlation between study quality and intervention effect size. Larger treatment effect sizes were found among participants with a heavier BMI. Research Report: This study used a non-randomized experimental design to determine the impact of brief mirror exposure on a non-clinical sample of women with a healthy body mass index (BMI) and women with an overweight/obese BMI. It examined the moderating effect of reassurance-seeking, social anxiety, and body avoidance. Forty-six women completed a battery of measures and undertook a 15-minute mirror exposure intervention. Analyses showed that mirror exposure was effective at improving the body perception and satisfaction of overweight/obese women. Reassurance-seeking, social anxiety, and body image avoidance did not affect the impact of mirror exposure.

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Lassalle, Guillaume. "Exploitation of hyperspectral data for assessing vegetation health under exposure to petroleum hydrocarbons." Thesis, Toulouse, ISAE, 2019. http://www.theses.fr/2019ESAE0030.

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L’exploration pétrolière et le monitoring de la contamination demeurent très limités dans les régions coloniséespar la végétation. La présence de suintements naturels et de fuites d’installations pétrolières est bien souventmasquée par le feuillage, rendant inopérantes les technologies actuelles de détection du pétrole brut et des produitspétroliers. L’exposition de la végétation à ces composés affecte toutefois son état de santé et, par conséquent, sespropriétés optiques dans le domaine [400:2500] nm. Cela suggère de pouvoir détecter les suintements et les fuitesd’installations de manière indirecte, en analysant l’état de santé de la végétation au travers de sa réflectancespectrale. Basée sur cette hypothèse, la présente thèse évalue le potentiel de l’imagerie hyperspectrale aéroportéeà très haute résolution spatiale pour détecter et quantifier la contamination pétrolière en région tempéréevégétalisée. Pour cela, une approche multi-échelles en trois étapes a été adoptée. La première étape a eu pourobjet de développer une méthode de détection et de caractérisation de la contamination en conditions contrôlées,exploitant les propriétés optiques de Rubus fruticosus L. La méthode proposée combine 14 indices de végétationen classification et permet de détecter divers contaminants pétroliers avec précision, depuis l’échelle de la feuillejusqu’à celle du couvert. Son utilisation en conditions naturelles a été validée sur un bourbier de productioncontaminé, colonisé par la même espèce. Au cours de la seconde étape, une méthode de quantification deshydrocarbures pétroliers totaux, basée sur l’inversion d’un modèle de transfert radiatif, a été développée. Cetteméthode exploite le contenu en pigments des feuilles, estimé à partir de leur signature spectrale, afin de prédireprécisément le taux de contamination en hydrocarbures du sol. La dernière étape de l’approche a démontré larobustesse des deux méthodes en imagerie aéroportée. Celles-ci se sont montrées très performantes pour détecteret quantifier la contamination des bourbiers. Une autre méthode de quantification, basée sur la régressionmultiple, a également été proposée. Au terme de cette thèse, les trois méthodes proposées ont été validées pourune utilisation sur le terrain, à l’échelle de la feuille et du couvert, ainsi qu’en imagerie hyperspectrale aéroportéeà très haute résolution spatiale. Leurs performances dépendent toutefois de l’espèce, de la saison et du niveau decontamination du sol. Une approche similaire a été conduite en conditions tropicales, permettant de mettre aupoint une méthode de quantification de la contamination adaptée à ce contexte. En vue d’une utilisationopérationnelle, un effort important reste nécessaire pour étendre le champ d’application des méthodes à d’autrescontextes et envisager leur application sur les futurs capteurs hyperspectraux embarqués sur satellite et sur drone.Enfin, l’apport de la télédétection active (radar et LiDAR) est à considérer dans les recherches futures, afin delever certaines limites propres à l’utilisation de la télédétection optique passive
Oil exploration and contamination monitoring remain limited in regions covered by vegetation. Natural seepages and oil leakages due to facility failures are often masked by the foliage, making ineffective the current technologies used for detecting crude oil and petroleum products. However, the exposure of vegetation to oil affects its health and, consequently, its optical properties in the [400:2500] nm domain. This suggest being able to detect seepages and leakages indirectly, by analyzing vegetation health through its spectral reflectance. Based on this assumption, this thesis evaluates the potential of airborne hyperspectral imagery with high spatial resolution for detecting and quantifying oil contamination in vegetated regions. To achieve this, a three-step multiscale approach was adopted. The first step aimed at developing a method for detecting and characterizing the contamination under controlled conditions, by exploiting the optical properties of Rubus fruticosus L. The proposed method combines 14 vegetation indices in classification and allows detecting various oil contaminants accurately, from leaf to canopy scale. Its use under natural conditions was validated on a contaminated mud pit colonized by the same species. During the second step, a method for quantifying total petroleum hydrocarbons, based on inverting the PROSPECT model, was developed. The method exploits the pigment content of leaves, estimated from their spectral signature, for predicting the level of hydrocarbon contamination in soils accurately. The last step of the approach demonstrated the robustness of the two methods using airborne imagery. They proved performing for detecting and quantifying mud pit contamination. Another method of quantification, based on multiple regression, was proposed. At the end of this thesis, the three methods proposed were validated for use both on the field, at leaf and canopy scales, and on airborne hyperspectral images with high spatial resolution. Their performances depend however on the species, the season and the level of soil contamination. A similar approach was conducted under tropical conditions, allowing the development of a method for quantifying the contamination adapted to this context. In a perspective of operational use, an important effort is still required for extending the scope of the methods to other contexts and for anticipating their use on satellite- and drone-embedded hyperspectral sensors. Finally, the contribution of active remote sensing (radar and LiDAR) should be considered in further research, in order to overcome some of the limits specific to passive optical remote sensing

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Nechvátalová, Ivana. "Bezpečnostní studie technologie galvanického pokovování." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2008. http://www.nusl.cz/ntk/nusl-228206.

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Submitted thesis deal with estimation safeness of electroplating technologi with reference to occurrence hazardous substances falls on man and environment. To identification diversification was used quantitative risk assessment and chemical exposure index.

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Marion, Jason W. "Protecting Public Health at Inland Ohio Beaches: Development of Recreational Water Quality Indicators Predictive of Microbial and Microcystin Exposure." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1313588302.

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Monteiro-Oliveira, Marcela Pinto 1982. "Relationship among nutritional status, caries, sugar exposure and social factors in 3-to-5-year-old preschoolers = Relação entre estado nutricional, cárie, exposição ao açúcar e fatores sociais em pré-escolares de 3 a 5 anos de idade." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/288088.

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Orientador: Marines Nobre dos Santos Uchoa
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
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Resumo: Este estudo transversal objetivou investigar a relação entre o estado nutricional, cárie dental, exposição diária ao açúcar e fatores sociais, assim como a presença de biofilme visível em 303 pré-escolares de 3 a 5 anos da cidade de Teresina-PI. A cárie dental foi determinada por meio do critério da Organização Mundial de Saúde (OMS) incluindo lesões iniciais de mancha branca (LMB). O peso e altura corporais foram mensurados e o Índice de massa corporal (IMC) obtido foi plotado em diagrama segundo gênero e faixa etária para obter-se o ranking do percentil segundo o Centers for Disease Control and Prevention (CDC). Os dados de exposição diária ao açúcar (líquido, sólido e total) foram obtidos pelo diário de dieta, usando-se a média de exposição diária de 72 horas. A presença de biofilme dental clinicamente visível nos incisivos superiores foi também registrada. Os fatores comportamentais e socioeconômicos foram coletados por meio de uma entrevista com as mães ou responsáveis pelas crianças. Os dados foram analisados por meio do teste qui quadrado seguido de regressão logística múltipla (? = 0,05, intervalo de confiança = 95%). Os resultados mostraram que 10,6% das crianças eram malnutridas, 17,2% tinham baixo peso, 44,9% apresentaram peso normal, 15,5% tinham sobrepeso e 11,9% eram obesos; 24,8% estavam livres de cárie e 75,2% apresentavam cárie precoce da infância (CPI). A média do ceo-s + LMB foi 10,8 (+ 11,2). Crianças com experiência de cárie apresentaram 0,3 mais chance de serem obesas do que aquelas livres de cárie (p = 0,0049). Da mesma forma, aquelas que consumiam líquidos açucarados mais de 2 vezes por dia apresentaram 2,7 mais chance de serem obesas (p = 0,0339). Nenhuma associação foi encontrada ente cárie e sobrepeso (p = 0,3640) e a presença de biofilme dental (p= 0,3190). Crianças que apresentaram o hábito de dormir com a mamadeira mostraram 2,3 vezes mais chance de terem baixo peso do que aquelas sem esse hábito (p = 0,0174). O gênero feminino apresentou a probabilidade 0,3 vezes maior de serem malnutridas do que o masculino (p = 0,00797). Além disso, pré-escolares com a presença de biofilme dental tiveram 3,1 vezes mais chance de serem malnutridas do que aquelas sem biofilme visível (p = 0,0247). Este estudo mostrou que houve relação entre experiência de cárie, consumo de líquidos açucarados e obesidade. Também mostrou relação entre o uso da mamadeira noturna e baixo peso na infância. Fatores socioeconômicos não foram relacionados ao estado nutricional da criança
Abstract: This cross-sectional study aimed to investigate the relationship among body mass index (BMI), dental caries, sugar exposure and social factors, as well as the presence of visible biofilm in 303 three-to-five-year-old preschoolers in the city of Teresina-PI, Brazil. Dental caries was recorded according to the World Health Organization criteria (WHO) + early caries lesions (ECL). Body weight/height was determined and BMI was calculated. Data regarding the sugar exposure was recorded using the mean exposure of 72-hour recall diet frequency chart. The presence of clinically visible dental biofilm on maxillary incisors was also recorded. Behavioral and social economic status of the study subjects were assessed using an interview applied to the mother. Data were analyzed by chi-square test followed by multiple logistic regression analysis (? = 0.05, confidence interval = 95%). The results showed that 10.6% of the children were malnourished, 17.2% were underweight, 44.9% had health weight, 15.5% were at risk of overweight, and 11.9% were obese; 24.8% were caries free and 75.2% had early childhood caries (ECC). The mean dmfs score was 10.8 (± 11.2). Preschool children with ECC were 0.3 times more likely to be obese than caries free children (p = 0.0049). In the same way, those who consumed liquid sugar more than 2 times a day, were 2.7 times more likely to be obese (p = 0.0339). No association was found between overweight and caries (p=0.3640) and dental biofilm (p= 0.3190). Preschool children who slept with a bottle were 2.3 times more likely to have underweight than children who did not sleep with a bottle (p = 0.0174). Female preschool children were 0.3 times more likely to be malnourished than boys (p = 0.00797). Moreover, preschool children with presence of dental biofilm were 3.1 times more likely to be malnourished than children with absent biofilm (p = 0.0247). In conclusion, our results suggest that preschool children having early childhood caries and a high liquid sugar consumption were more likely to be obese and those who were bottle fed during the night showed a higher chance of having underweight
Doutorado
Odontopediatria
Doutora em Odontologia

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Nedomová, Lenka. "Posouzení bezpečnosti chladicí stanice." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2008. http://www.nusl.cz/ntk/nusl-228346.

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Estimation of cooling station safety Diploma thesis, institute of metrology and quality assurance and testing, Brno University of Technology. The diploma thesis deals with safety evaluation of cooling plant at a pool stadium, which uses amonia as a coolant. The work includes particular calculation (quantitative risk estimation) of cooling the plant with amonia. For cooling at the pool stadium no salt water, only amonia is used, so it is direct cooling. The safety of population, animals and enviroment is considered. Part of this thesis is also the estimation of the chemical exposure index (CEI) and simulation of breakdown effects with ALOHA model (Areal Locations of Hazardous Atmospheres). At the end FMEA method is used, the method cause – effect.

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Bigelow, Dyk Melinda Michelle. "Determinants of human exposure to Fipronil following use as a topical flea and tick treatment of companion animals." Diss., UC access only, 2009. http://proquest.umi.com/pqdweb?index=44&did=1905733921&SrchMode=1&sid=2&Fmt=7&retrieveGroup=0&VType=PQD&VInst=PROD&RQT=309&VName=PQD&TS=1270145414&clientId=48051.

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Thesis (Ph. D.)--University of California, Riverside, 2009.
Includes abstract. Includes bibliographical references (leaves 201-210). Issued in print and online. Available via ProQuest Digital Dissertations.

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Pilkytė, Laima. "Radionuklidų savitojo aktyvumo statybinėse medžiagose Lietuvoje eksperimentinis tyrimas, jų sukeltos apšvitos modeliavimas ir vertinimas." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2006. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2006~D_20061109_193015-36445.

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The study is devoted to problems of exposure caused by radionuclides in construction materials. Results received by gamma measurements and calculations (dose modeling) are used. Construction materials produced and/or used in Lithuania were investigated. The results of measurements (concentrations of natural radionuclides and activity indexes) are given for different types of construction materials. On the basis of these results and peculiarities of use of construction materials they have been classified according to their radiological significance. It helps to determine possible amounts of construction materials to be investigated and priorities of investigations. Relationship between activity indexes of different construction materials and dose rates in premises constructed of these construction materials has been determined. It might be used for increase of precision of personal dosimetric measurements performed in premises constructed of different materials. Possible relationship between absorbed dose rate indoors and concentration of indoor radon is discussed. Results of measurements of concentrations of natural radionuclides in archeological samples of construction materials are also presented and discussed. Dose modeling has been performed with the help of ALARA planning tool Visiplan 3D. Distributions of absorbed dose rate in standard living premises have been determined, relationship between dose rate and different parameters of constructions, such as thickness... [to full text]

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Li, Yanhong. "Occurrence and the exposure potential of selected pesticide residues in strawberries, particularly preformed human malathion biomarkers in leaves and berries." Diss., UC access only, 2009. http://proquest.umi.com/pqdweb?index=113&did=1871875451&SrchMode=1&sid=1&Fmt=7&retrieveGroup=0&VType=PQD&VInst=PROD&RQT=309&VName=PQD&TS=1270486529&clientId=48051.

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Smith, Michael Derrick. "Developmental effects in zebrafish (Danio rerio) following exposure to benzo[a]pyrene, diesel particulate matter and retinoic acid : a comparative study/." Full text available from ProQuest UM Digital Dissertations, 2009. http://0-proquest.umi.com.umiss.lib.olemiss.edu/pqdweb?index=0&did=1800249061&SrchMode=1&sid=1&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1268250038&clientId=22256.

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Thesis (Ph.D.)--University of Mississippi, 2009.
Typescript. Vita. "May 2009." Major professor: Dr. Stephen D'Surney Includes bibliographical references (leaves 112-186). Also available online via ProQuest to authorized users.

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Wilson, Brenda Chaffin. "A newspaper reading habit in college students: family newspaper literacy practices, K-12 newspaper exposure, and civic interest : a dissertation presented to the faculty of the Graduate School, Tennessee Technological University /." Click to access online version, 2007. http://proquest.umi.com/pqdweb?index=66&did=1400959021&SrchMode=1&sid=1&Fmt=6&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1254944459&clientId=28564.

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Wan, Margaret. "Assessment of occupational heat strain." [Tampa, Fla] : University of South Florida, 2006. http://purl.fcla.edu/usf/dc/et/SFE0001661.

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Lavelle, Karlene Sellani Olshan Andrew F. "Effects of lifestyle exposures and body mass index on sperm quality parameters of fertile men." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2008. http://dc.lib.unc.edu/u?/etd,1857.

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Thesis (Ph. D.)--University of North Carolina at Chapel Hill, 2008.
Title from electronic title page (viewed Dec. 11, 2008). "... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Epidemiology, School of Public Health." Discipline: Epidemiology; Department/School: Public Health.

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Nemeth, Julianna Maria. "Intimate Partner and/or Sexual Gender-based Violence and Smoking in Ohio Appalachia." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1429731984.

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Faustini, Fabiana Benevenuto. "Conforto térmico e tempo de permanência em espaços abertos de lazer : Influência de diferentes níveis de sombreamento /." Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/157133.

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A sensação de conforto térmico experimentada pelos usuários de espaços abertos de lazer, como praças, parques, bosques, entre outros, pode afetar positiva ou negativamente a quantidade de usuários, atividades desenvolvidas, além do tempo de permanência das pessoas. No entanto, essa relação entre conforto térmico e tempo de permanência ainda é pouco estudada, fato que justifica a importância desta pesquisa, que busca investigar essa relação em um espaço aberto de lazer. O estudo foi desenvolvido em um parque Zoológico, na cidade de Bauru-SP, através da coleta de dados objetivos (medições microclimáticas e quantificação de pessoas), e subjetivos (aplicação de questionários) em dois subespaços com mesma atratividade (área de felinos) e diferentes Fatores de Visão do Céu (FVC), em duas condições de tempo, quente e ameno. Esses dados permitiram identificar os Votos de Sensação Real (ASV), calcular o índice PET (Temperatura Equivalente Fisiológica), verificar a preferência térmica dos usuários e registrar o tempo de permanência em cada subespaço, nas condições de tempo analisadas. Os resultados evidenciam a estreita relação entre FVC e o tempo de permanência em determinado espaço. Destaca-se ainda: 1. Maior frequência de sensação térmica de conforto dos usuários na área com maior sombreamento, nas condições de tempo quente, e frequências de sensação térmica equivalentes nos dois subespaços em condições de tempo ameno. 2. Nas condições de tempo quente, permanência de curta duração dos usuários nas áreas de alta incidência de radiação solar direta e faixa de neutralidade do índice PET variada em relação aos dois subespaços. 3. Em situações de desconforto por calor, o tempo de permanência é reduzido em função do FVC, e a atração passa a ser um aspecto secundário, ou seja, o maior interesse se torna a busca por um local mais confortável.
The sensation of thermal comfort experienced by the users of leisure open places, such as squares, parks, woods, among others, may positively or negatively affect the amount of users, developed activities, and permanency time of people. However, this relation between thermal comfort and exposure time is still poorly studied, fact that justifies the importancy of this research, that seeks to investigate this relation in an leisure open place. The study was developed in a Zoo Park, in Bauru-SP, trough objective data collect (microclimatic measurements and quantification of people), and subjective data collect (questionnaires application) in two subspaces with the same attractiveness (feline area) and different Sky View Factors (SVF), under two weather conditions, hot and mild. These data allowed to indentify the Actual Sensation Votes (ASV), to calculate the PET index (Physiological Equivalent Temperature), verify the thermal preference of the users and record the exposure time in each subspace, under the microclimatic conditions analyzed. The results show the narrow relation between SVF and the exposure time in a given space. It also shows: 1. Higher frequency of thermal sensation of comfort of the users in the area with greater shading, in hot weather conditions, and equivalent thermal sensation frequencies in the two subspaces in mild weather conditions. 2. In hot weather conditions, permanency of short duration of the users in the areas of high incidence of direct solar radiation and neutrality range of the PET index varied in relation to the two subspaces. 3. In situations of heat discomfort, the permanecy time is reduced in function of the SVF, and the attraction turns into a secondary aspect, that is, the greater interest becomes the search for a more comfortable place.

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Lyckeberg, Sara. "Commodity exposures and risk management in the Swedish construction sector : A comparison between Skanska, NCC, Peab and JM." Thesis, Uppsala universitet, Industriell teknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-192613.

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Today’s construction industry consists of fierce competition and low margins, resulting in companies focusing on cost risk awareness. The aim of this thesis was to investigate how construction companies manage their market risks, with a special focus on commodity risks. In addition, the thesis purpose was also to explore the composition of commodity exposures within a few selected construction companies. A financial index of commodity exposures was generated out of Statistiska Centralbyråns’ totala faktorprisindex for multi-residence housing projects. Furthermore, a fictional case was combined to test the risk management effect of the financial index, using Sweden’s four largest construction companies’ commodity exposures. In summary, the construction companies were all aware of their commodity exposures although most of them did not actively manage them or know their exposures extent. Moreover, financial risk management of commodities is not easy or straightforward, resulting in difficulties in choosing the right management tool. Therefore, this thesis created and illustrated how a financial index could be used as a way to stabilize the profitability in construction projects.

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Ruiz, Castell María de la Concepción 1981. "Environmental contamination and infant development in a Bolivian mining city." Doctoral thesis, Universitat Pompeu Fabra, 2012. http://hdl.handle.net/10803/109261.

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Background: Oruro is a mining city in the Bolivian highlands. Most of its citizens are exposed to polymetalic cocktails. This study aims to determine whether the neuropsychological development of one year-old children can be associated with 1) polymetalic exposures and/or 2) growth patterns. Methods: The thesis builds from data collected by the ToxBol multidisciplinary project. The health task was centred on the follow-up of a birth-cohort that set to evaluate child development. Children were examined at 11 and 12 months of age using the Bayley Scale of Infant Development (BSID). Results: 1) Analyses revealed no high concentrations of metals in the blood of pregnant women. 2) No neuropsychological anomalies were observed in association with metal concentrations or growth patterns. 3) A positive association was observed between low lead values in blood and the neuropsychological development of children. 4) During the first 6 months of life, growth rate was negatively associated with weight at birth and positively associated with the BMI at 12 months of age. Conclusion: Although heavy metallic pollution was demonstrated by environmental studies, unexpected low levels of exposure were registered from pregnant women. Neither the level of exposure to metals nor the growth patterns appear to have an impact on child neuropsychological development. We argue that the positive effect that was observed in association to lead might be caused by factors such as diet.
Antecedentes: Oruro es una ciudad minera del altiplano boliviano. Muchos de sus habitantes están expuestos a un cóctel polimetálico. El objetivo principal es el de determinar si existe una asociación entre desarrollo neuropsicológico de los niños de un año y 1) la exposición polimetálica y/o 2) los patrones de crecimiento. Métodos: Esta tesis está basada en los datos recogidos del Proyecto multidisciplinario ToxBol. Se realizó el seguimiento de una cohorte de niños para evaluar su desarrollo. Para evaluar el desarrollo neuropsicológico de los niños se utilizaron las escalas de Bayley de desarrollo infantil (BSID). Resultados: 1) No se observaron altas concentraciones de metales en sangre de las mujeres embarazadas. 2) No se observaron anormalidades neuropsicológicas en relación con concentraciones de metales o patrones de crecimiento. 3) Se observó una asociación positiva entre exposiciones bajas de plomo y el desarrollo neuropsicológico del niño al año de vida. 4) La velocidad de crecimiento, desde el nacimiento hasta los 6 meses, se asoció negativamente con el peso al nacer y positivamente con el BMI a los 12 meses. Conclusión: A diferencia de lo demostrado en otros estudios epidemiológicos, se observó una inesperada baja exposición. No se observó una relación entre el grado de exposición a metales- o los patrones de crecimiento -y el desarrollo neuropsicológico del niño. El efecto positivo del plomo creemos que se debe a otros factores como la dieta.
Antecedents: Oruro es una ciutat minera del altiplà Bolivià. La població es troba es contacte amb fonts de contaminación polimetàlica. L’objectiu principal es el de determinar si existeix una associació entre el desenvolupament neuropsicològic dels nens d’un any i 1) la exposició polimetálica i/o 2) patrons de creixement. Mètodes: Esta tesi està basada en dades del Projecte multidisciplinari ToxBol. La tasca de salut es va centrar en el seguiment del desenvolupament d’una cohort de nens. El desenvolupament neuropsicològic infantil es va avaluar amb les escales de Baley de Desenvolupament infantil (BSID). Resultats: 1) No es van observar concentracions altes de metalls en sang de les dones embarassades. 2) No es va observar anormalitats neuropsicològiques en realció amb les concentracions de metalls o patrons de creixement. 3) Es va observar una associació positiva entre concentracions baixes de plom en sang i el desenvolupament neuropsicològic dels nens d’un any. 4) La velocitat de creixement, des del naixement fins els 6 mesos, es va associar negativament amb el pes al néixer i positivament amb el BMI als 12 mesos. Conclusió: A diferencia del que esperàvem, es van registrar baixes concentracions de metalls a les dones embarassades. Tampoc s’observa una relació entre el grau d’exposició a metalls, o patrons de creixement, i el desenvolupament neuropsicològic del nens. El efecte positiu que observem del plom, pensem que es deu a altres factors com la dieta.

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Harirforoush, Homayoun. "An integrated GIS-based and spatiotemporal analysis of traffic accidents: a case study in Sherbrooke." Thèse, Université de Sherbrooke, 2017. http://hdl.handle.net/11143/10574.

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Abstract: Road traffic accidents claim more than 1,500 lives each year in Canada and affect society adversely, so transport authorities must reduce their impact. This is a major concern in Quebec, where the traffic-accident risks increase year by year proportionally to provincial population growth. In reality, the occurrence of traffic crashes is rarely random in space-time; they tend to cluster in specific areas such as intersections, ramps, and work zones. Moreover, weather stands out as an environmental risk factor that affects the crash rate. Therefore, traffic-safety engineers need to accurately identify the location and time of traffic accidents. The occurrence of such accidents actually is determined by some important factors, including traffic volume, weather conditions, and geometric design. This study aimed at identifying hotspot locations based on a historical crash data set and spatiotemporal patterns of traffic accidents with a view to improving road safety. This thesis proposes two new methods for identifying hotspot locations on a road network. The first method could be used to identify and rank hotspot locations in cases in which the value of traffic volume is available, while the second method is useful in cases in which the value of traffic volume is not. These methods were examined with three years of traffic-accident data (2011–2013) in Sherbrooke. The first method proposes a two-step integrated approach for identifying traffic-accident hotspots on a road network. The first step included a spatial-analysis method called network kernel-density estimation. The second step involved a network-screening method using the critical crash rate, which is described in the Highway Safety Manual. Once the traffic-accident density had been estimated using the network kernel-density estimation method, the selected potential hotspot locations were then tested with the critical-crash-rate method. The second method offers an integrated approach to analyzing spatial and temporal (spatiotemporal) patterns of traffic accidents and organizes them according to their level of significance. The spatiotemporal seasonal patterns of traffic accidents were analyzed using the kernel-density estimation; it was then applied as the attribute for a significance test using the local Moran’s I index value. The results of the first method demonstrated that over 90% of hotspot locations in Sherbrooke were located at intersections and in a downtown area with significant conflicts between road users. It also showed that signalized intersections were more dangerous than unsignalized ones; over half (58%) of the hotspot locations were located at four-leg signalized intersections. The results of the second method show that crash patterns varied according to season and during certain time periods. Total seasonal patterns revealed denser trends and patterns during the summer, fall, and winter, then a steady trend and pattern during the spring. Our findings also illustrated that crash patterns that applied accident severity were denser than the results that only involved the observed crash counts. The results clearly show that the proposed methods could assist transport authorities in quickly identifying the most hazardous sites in a road network, prioritizing hotspot locations in a decreasing order more efficiently, and assessing the relationship between traffic accidents and seasons.
Les accidents de la route sont responsables de plus de 1500 décès par année au Canada et ont des effets néfastes sur la société. Aux yeux des autorités en transport, il devient impératif d’en réduire les impacts. Il s’agit d’une préoccupation majeure au Québec depuis que les risques d’accidents augmentent chaque année au rythme de la population. En réalité, les accidents routiers se produisent rarement de façon aléatoire dans l’espace-temps. Ils surviennent généralement à des endroits spécifiques notamment aux intersections, dans les bretelles d’accès, sur les chantiers routiers, etc. De plus, les conditions climatiques associées aux saisons constituent l’un des facteurs environnementaux à risque affectant les taux d’accidents. Par conséquent, il devient impératif pour les ingénieurs en sécurité routière de localiser ces accidents de façon plus précise dans le temps (moment) et dans l’espace (endroit). Cependant, les accidents routiers sont influencés par d’importants facteurs comme le volume de circulation, les conditions climatiques, la géométrie de la route, etc. Le but de cette étude consiste donc à identifier les points chauds au moyen d’un historique des données d’accidents et de leurs répartitions spatiotemporelles en vue d’améliorer la sécurité routière. Cette thèse propose deux nouvelles méthodes permettant d’identifier les points chauds à l’intérieur d’un réseau routier. La première méthode peut être utilisée afin d’identifier et de prioriser les points chauds dans les cas où les données sur le volume de circulation sont disponibles alors que la deuxième méthode est utile dans les cas où ces informations sont absentes. Ces méthodes ont été conçues en utilisant des données d’accidents sur trois ans (2011-2013) survenus à Sherbrooke. La première méthode propose une approche intégrée en deux étapes afin d’identifier les points chauds au sein du réseau routier. La première étape s’appuie sur une méthode d’analyse spatiale connue sous le nom d’estimation par noyau. La deuxième étape repose sur une méthode de balayage du réseau routier en utilisant les taux critiques d’accidents, une démarche éprouvée et décrite dans le manuel de sécurité routière. Lorsque la densité des accidents routiers a été calculée au moyen de l’estimation par noyau, les points chauds potentiels sont ensuite testés à l’aide des taux critiques. La seconde méthode propose une approche intégrée destinée à analyser les distributions spatiales et temporelles des accidents et à les classer selon leur niveau de signification. La répartition des accidents selon les saisons a été analysée à l’aide de l’estimation par noyau, puis ces valeurs ont été assignées comme attributs dans le test de signification de Moran. Les résultats de la première méthode démontrent que plus de 90 % des points chauds à Sherbrooke sont concentrés aux intersections et au centre-ville où les conflits entre les usagers de la route sont élevés. Ils révèlent aussi que les intersections contrôlées sont plus à risque par comparaison aux intersections non contrôlées et que plus de la moitié des points chauds (58 %) sont situés aux intersections à quatre branches (en croix). Les résultats de la deuxième méthode montrent que les distributions d’accidents varient selon les saisons et à certains moments de l’année. Les répartitions saisonnières montrent des tendances à la densification durant l’été, l’automne et l’hiver alors que les distributions sont plus dispersées au cours du printemps. Nos observations indiquent aussi que les répartitions ayant considéré la sévérité des accidents sont plus denses que les résultats ayant recours au simple cumul des accidents. Les résultats démontrent clairement que les méthodes proposées peuvent: premièrement, aider les autorités en transport en identifiant rapidement les sites les plus à risque à l’intérieur du réseau routier; deuxièmement, prioriser les points chauds en ordre décroissant plus efficacement et de manière significative; troisièmement, estimer l’interrelation entre les accidents routiers et les saisons.

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Klein, Achim. "Annoyance indicators for various urban road vehicle pass-by noises and urban road traffic noise combined with tramway noise." Thesis, Vaulx-en-Velin, Ecole nationale des travaux publics, 2015. http://www.theses.fr/2015ENTP0002/document.

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La pollution sonore est un problème majeur pour les résidents des zones urbaines. La directive Européenne 2002/49/CE impose aux états membres l’établissement de cartes de bruit. Ces dernières sont construites sur la base de l’indice énergétique Lden, également utilisé dans les relations dose-effet établies pour prédire la gêne. Toutefois, pour l’évaluation de la gêne due au bruit dans les zones urbaines, la pertinence de cet indice est souvent remise en question. En effet, de nombreuses études ont montré que les caractéristiques temporelles et spectrales des bruits environnementaux influencent aussi les réponses de gêne et ne sont pas prises en compte dans cet indice. Cette thèse vise à contribuer à l’amélioration de la caractérisation de la gêne due au bruit des véhicules routiers en ville. Elle est basée sur des expériences réalisées en laboratoire. Elle comprend deux parties principales. La première partie a comme objectif de progresser sur la caractérisation physique et perceptive du bruit des passages de divers véhicules routiers en milieu urbain tels que les bus, les deux-roues motorisés, les poids lourds et les véhicules légers. Une attention particulière a été portée sur la caractérisation de la gêne due aux deuxroues motorisés qui sont cités parmi les véhicules routiers les plus gênants et sont peu étudiés dans la littérature. Dans cette perspective, un indicateur acoustique caractéristique de la gêne due au bruit routier urbain a été déterminé : il rend compte de différents attributs auditifs gênants en associant la sonie, un indice spectral et deux indices de modulation proposés dans le cadre de ces travaux. Dans les zones urbaines, les riverains sont souvent exposés à la circulation routière en présence d’autres sources de bruit de l’environnement. L’objectif principal de la deuxième partie est la prédiction de la gêne totale due au bruit du trafic routier urbain combiné avec le bruit de tramway. Dans le but de caractériser la gêne totale, les phénomènes perceptifs liés à la combinaison de ces bruits sont tout d’abord étudiés. Ensuite, l’indicateur proposé précédemment pour caractériser la gêne due au bruit des passages de différents véhicules routiers est testé lorsque différents trafics routiers urbains sont considérés. Sur la base de ces résultats, des modèles permettant de caractériser la gêne due au bruit de trafic routier urbain combiné au bruit de tramway ont été proposés
Noise pollution is a major concern for residents of urban areas. To date, the European directive 2002/49/CE requires member states to represent community noise through noise maps. These are produced using the Lden (day-evening-night level) index which is also employed for dose-effect relationships in noise annoyance prediction. However, for the assessment of noise annoyance in urban areas, its relevance is often questioned. Numerous studies have shown that noise annoyance due to community noise is not solely based on the sound pressure level and other acoustical signal characteristics such as temporal and spectral features influence noise annoyance ratings. This thesis aims to improve the assessment of noise annoyance due to various road vehicle noises in cities. It is based on experiments carried out in laboratory conditions and comprises two main parts. The first addresses the enhancement of the physical and perceptual characterization of annoyance due to various urban road vehicle pass-by noises, such as buses, poweredtwo- wheelers, heavy vehicles and light vehicles. A specific focus is put on the characterization of annoyance due to powered-two-wheelers which are among the most annoying road vehicles and studied little in the existing literature. An indicator accounting for annoyance-relevant auditory attributes of urban road vehicle pass-by noises is determined: it comprises loudness, a spectral index and two modulation indices proposed in this work. In urban agglomerations, people are often exposed to road traffic in presence of a variety of other environmental noise sources. The focal point of the second part is on the prediction of total annoyance due to urban road traffic noise combined with tramway noise. In the aim of adequately characterizing total annoyance, first the perceptual phenomena involved in annoyance due to the combination of the sources are studied. Furthermore, the analysis allows for the testing of the proposed noise annoyance indicator for the characterization of urban road traffic noise. To characterize annoyance due to tramway noise, an indicator determined in a recent study is employed. Based on these indicators and the findings regarding perceptual phenomena, models for the prediction of total annoyance due to combined urban road traffic and tramway noise are proposed

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Jones, Esther Lane. "Spatial ecology of marine top predators." Thesis, University of St Andrews, 2017. http://hdl.handle.net/10023/12278.

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Species distribution maps can provide important information to focus conservation efforts and enable spatial management of human activities. Two sympatric marine predators, grey seals (Halichoerus grypus) and harbour seals (Phoca vitulina), have overlapping ranges but contrasting population dynamics around the UK; whilst grey seals have generally increased, harbour seals have shown significant regional declines. A robust analytical methodology was developed to produce maps of grey and harbour seal usage estimates with corresponding uncertainty, and scales of spatial partitioning between the species were found. Throughout their range, both grey and harbour seals spend the majority of their time within 50 km of the coast. The scalability of the analytical approach was enhanced and environmental information to enable spatial predictions was included. The resultant maps have been applied to inform consent and licensing of marine renewable developments of wind farms and tidal turbines. For harbour seals around Orkney, northern Scotland, distance from haul out, proportion of sand in seabed sediment, and annual mean power were important predictors of space-use. Utilising seal usage maps, a framework was produced to allow shipping noise, an important marine anthropogenic stressor, to be explicitly incorporated into spatial planning. Potentially sensitive areas were identified through quantifying risk of exposure of shipping traffic to marine species. Individual noise exposure was predicted with associated uncertainty in an area with varying rates of co-occurrence. Across the UK, spatial overlap was highest within 50 km of the coast, close to seal haul outs. Areas identified with high risk of exposure included 11 Special Areas of Conservation (from a possible 25). Risk to harbour seal populations was highest, affecting half of all SACs associated with the species. For 20 of 28 animals in the acoustic exposure study, 95% CI for M-weighted cumulative Sound Exposure Levels had upper bounds above levels known to induce Temporary Threshold Shift. Predictions of broadband received sound pressure levels were underestimated on average by 0.7 dB re 1μPa (± 3.3). An analytical methodology was derived to allow ecological maps to be quantitatively compared. The Structural Similarity (SSIM) index was enhanced to incorporate uncertainty from underlying spatial models, and a software algorithm was developed to correct for internal edge effects so that loss of spatial information from the map comparison was limited. The application of the approach was demonstrated using a case study of sperm whales (Physeter macrocephalus, Linneaus 1758) in the Mediterranean Sea to identify areas where local-scale differences in space-use between groups and singleton whales occurred. SSIM is applicable to a broad range of spatial ecological data, providing a novel tool for map comparison.

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Aasa, Ulrika. "Ambulance Work : Relationships between occupational demands, individual characteristics and health-related outcomes." Doctoral thesis, Umeå : Umeå universitet, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-478.

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Valvi, Damaskini 1983. "Effects of endocrine disrupting chemicals on childhood growth and obesity : evidence from the Spanish INMA Birth Cohort Study." Doctoral thesis, Universitat Pompeu Fabra, 2014. http://hdl.handle.net/10803/320194.

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Acumulada evidencia en estudios experimentales sugiere que la exposición a contaminantes capaces de interrumpir el sistema endocrino podría alterar las vías moleculares de los procesos de regulación hormonal y epigenética que están involucrados en el desarrollo del tejido adiposo y la homeostasia energética, lo que incrementaría la susceptibilidad de los individuos a ser obesos. La evidencia de esta emergente “Hipótesis de los Obesógenos Ambientales” en estudios humanos es escasa y se basa mayoritariamente en datos transversales. Por este motivo, el objetivo principal de la presente tesis fue evaluar los efectos de la exposición prenatal a compuestos orgánicos persistentes (COPs) y a los compuestos orgánicos no persistentes, BPA y ftalatos, en el crecimiento y la obesidad durante la infancia. Los datos que se utilizaron en esta tesis provienen del estudio poblacional de cohortes de nacimiento en España “Infancia y Medio Ambiente”-INMA. Los hallazgos sugieren que la exposición prenatal a COPs, ftalatos y de forma menos evidente a BPA, podrían influir en el crecimiento y la obesidad durante la infancia y que el sentido de estas asociaciones puede diferir según el contaminante y el sexo del niño.
A growing body of experimental evidence suggests that exposure to endocrine disrupting chemicals during the critical windows of development may alter the molecular pathways that underlie the hormonal and epigenetic regulation of adipose tissue development and energy homeostasis and thus, may increase individuals susceptibility towards obesity. Human evidence supporting this emerging “Environmental Obesogen Hypothesis” is still scarce and largely relies on cross-sectional data. Thus, the main scope of the present thesis was to prospectively evaluate the influences of prenatal exposures to persistent organic pollutants (POPs) and the non-persistent organic pollutants, BPA and phthalates, on childhood growth and obesity. Data used in this thesis come from the population-based INMA-“INfancia y Medio Ambiente” Birth Cohort Project in Spain. Findings suggest that prenatal exposures to POPs, phthalates and less clearly BPA may influence childhood growth and obesity and that the direction of the effects may differ according to the chemical tested and child sex.

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YingShen and 沈穎. "The development of Biological monitoring index for vinyl chloride exposure workers." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/92695354743795647824.

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碩士
國立成功大學
環境醫學研究所
100
According to the Toxic Chemicals Database of Environmental Protection Administration, the production quantity of Vinyl Chloride Monomer (VCM) in Taiwan was 2 million tons per year. VCM exposure has been associated with toxicity of the liver and was classified as a group 1 carcinogen by IARC (1987). Due to the extremely volatile property, the major exposure route is inhalation. The main urinary metabolites of VCM is thiodiglycolic acid (TDGA). Urinary TDGA could be detected by GS/MS method, but the higher detection limit (〉1 mg/L) was the limitation for low exposure workers. In order to assess the relationship of low exposure level of VCM and health risk, the development of a precise and accurate analytical method for measurement of urinary TDGA is needed. The high performance liquid chromatography electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) was used as qualitative and quantitative analytical instrument. Two VCM manufacturing plants were selected based on the recruited criteria with operation amount of VCM (〉 500 tons/ year), number of employees, and process conditions. Pre- and post-shift urine samples were collected from each VCM exposed worker and urinary TDGA were analyzed as analytical method field validation. We also used urinary TDGA to calculated VCM exposure dose for health risk assessment. Atlantis HILIC Silica (2.1 x150mm, 3μm) was used to separate TDGA, and 4-nitrobenzoic acid (internal standard, IS). The mobile phases were acetonitrile and LC grade water (containing 0.2% formic acid). The calibration curve was ranged from 5 to 1000 ng/mL (R2 〉 0.995), spike recovery was set between 70% and 130%, the method detection limit (MDL) is 1.34 ng/mL, and TDGA concentration of blank sample was lower than twice of MDL. Forty workers in two VCM operating plants were recruited as subject, and 80 urine samples (pre- and post-shift urine sample for each subject) had been collected. The median (range) of the urinary TDGA levels in the post-shift (347.22 g/g- Cre, 48.41-1914.17) were significantly higher than those of pre-shift (311.23 g/g-Cre, 15.44-1232.66) (p〈0.05). We also use the metabolic percentage of urinary TDGA of different exposure routes to back-estimate the daily intake (DI Urine) and airborne exposure levels of VCM for each worker. Du to the carcinogenicity of VCM, it is important to assess the noncarcinogenic and carcinogenic risk of VCM exposure workers. The noncarcinogenic hazard index (HI) is 0.033 (0.0044-0.18) and carcinogenic risk were 9.0×10-5 (1.26×10-5-5.06×10-4)、1.09×10-4 (1.47×10-5-5.91×10-4)及1.24×10-4 (1.68×10-5- 6.75×10-4) (for working 30, 35 and 40 year respectively ). The non-carcinogenic risk of VCM exposure is acceptable (HI〈1). And, the carcinogenic risk of VCM exposure for some workers were lower than acceptable level (1×10-3). We first set up the calculating model to assess VCM daily exposure dose with urinary TDGA. In the future, this model need to validate using more measured data.

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Hesson, Jacqueline Barbara. "Cumulative estrogen exposure and prospective memory in older women." Thesis, 2007. http://hdl.handle.net/1828/2404.

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With the average female life expectancy in Canada currently at 82 years, women are now spending approximately one-third of their lives in a hypoestrogenic state. Numerous studies from the basic sciences have shown that estrogen is neuroprotective in a variety of ways. The findings from the clinical studies of the effects of estrogen replacement on cognition in postmenopausal women are more inconsistent, though current research suggests that the timing of initiation of estrogen replacement relative to menopause is a major contributing factor to the discrepant findings in this literature. Reproductive and biological variables that affect levels of endogenous estrogen throughout a woman's lifespan may also influence cognitive function later in life as well as modify a woman's response to exogenous estrogen. The present study looked at the effects of cumulative estrogen exposure on the performance of a measure of prospective memory in a group of older postmenopausal women. Cumulative estrogen exposure was estimated using a mathematical index that included variables known to influence estrogen levels across the life span such as age at menarche and menopause, parity, duration of breastfeeding and estrogen replacement therapy, body mass index and time since menopause. Prospective memory is memory for future intentions and it was chosen because of its relevance for independent function and possible utility as an early indicator of dementia. Imaging studies link prospective memory to the prefrontal cortex, an area of the brain that is known to be influenced by estrogen so it was hypothesized that women with higher levels of cumulative estrogen exposure would perform better on a measure of prospective memory than women with lower levels of endogenous estrogen. Measures of verbal memory were also included in the study for comparative purposes as verbal memory is the cognitive function reported most consistently in the previous literature to be affected by postmenopausal estrogen replacement use. The results of the multivariate analyses indicated a significant positive correlation between prospective memory scores and cumulative estrogen exposure but only when women who had initiated estrogen replacement more than five years after menopause were excluded from the analysis. The significant positive correlation between cumulative estrogen exposure and prospective memory performance remained significant when only women who had never used estrogen were included in the analysis. No relationships were observed between levels of cumulative estrogen exposure and performance on measures of verbal memory. While the study was limited by the fact that it was observational in nature and the sample size was small, the results are consistent with recent findings from the hormone literature, in that they suggest that the timing of hormone replacement as well as the influence of variables that affect endogenous estrogen levels over a woman's lifespan need to be considered when studying relationships between cognitive performance and estrogen. In addition, the finding that performance on a measure of prospective memory but not performance on a measure of verbal memory was associated with levels of cumulative estrogen exposure adds further support to the theory that the frontal cortex may be especially sensitive to estrogen.

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Belle, Bharath Kumar. "Development of a dust exposure level index (Deli) for South African underground coal mine workers." Thesis, 2006. http://hdl.handle.net/10539/1859.

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Faculty of Engineering and the Built Environment, School of Mining
Inhaling excessive amounts of respirable coal dust will lead to work-related lung disease commonly known as Coal Worker’s Pneumoconiosis (CWP) or black lung. Prevention and control of CWP requires accurate knowledge of the dose-response relationship to set-up and review occupational exposure limits (OELs), which do not exist in SA. Due to historical reasons, poor emphasis of occupational health on the mines resulted in inadequate exposure data in SA. The new Mine Health and Safety Act (1996) overcame the deficiencies of the past and require quantifying the dust exposure and efficiency of dust control measures, and continuous risk assessments for dust exposure. The current method of exposure assessment is expressed using an Air Quality Index (AQI) which is the ratio of the measured dust level and OEL of coal dust. The difficulties with the usage of AQI are poor descriptions of dust problem areas and its magnitude, poor quality of the data leading to “no dust problem situation” and failure to extract information on ‘dose in milligram’ to relate them to the disease rate. Gravimetric size-selective dust sampling was introduced for the first time in 1990 in SA. Due to the lack of critically important coal dust exposure data available, this thesis has set out to examine several critical exposure related parameters and determine dust levels underground. This research study had the objective of the development of a pragmatic diagnostic tool (method) called the Dust Exposure Level Index (DELI) to evaluate the exposure of workers. The DELI incorporates a set of controllable parameters and influential areas and prioritises them to manage and reduce the worker exposure. The DELI model was to provide critical information as an index, i.e., to show whether the environment is dusty, border line or relatively free of dust and effectiveness of administrative and engineering dust control measures. The research work in this thesis has led to very explicit conclusions, which were based on extensive dust measurements in various coal mines over a five year period. Conclusions obtained for the various sets of controllable parameters used in the DELI model are as follows: 1. A previous analysis of the dust data during 1990 indicated that the dust levels have increased with mechanisation. The contamination of coal dust samples due to stone dusting can result in high dust levels giving a “false” indication of the efficiencies of the dust-control systems. 2. The dust exposure levels during coal cutting indicated that a worker positioned inside the cabin of a CM during the cutting of a 24 m coal block is at a higher dust exposure risk than the worker when cutting a 12 m coal block. Also, the miner who is operating in a heading is exposed to higher dust exposure risk than in a split. 3. The analyses of measured real-time dust data showed a clear relationship between the average dust levels and the frequency of occurrence of “peak” dust levels. The study demonstrated a clear method of using real-time dust data for assessing exposure. 4. The average measured section intake dust level was 0.80 mg/m3 and 60 % of the collected data exceeded the 0.5 mg/m3 limit indicating that this is a base dust level to which the worker is exposed without carrying out any additional work in the section. 5. The average measured section return dust level was greater than 2.0 mg/m3 indicating the high exposure levels of workers, and ineffectiveness of the ventilation and dustcontrol systems. 6. The results of this research study indicated that there is no conclusive relationship between the rate of coal production and respirable dust levels. Also, the type of dust control system used has pronounced effect on dust levels in the sections. The capture efficiency of any dust control system is not one hundred percent at any given time. During any cutting process for a given time and dust control type, part of the escaped respirable dust is added to the coal face atmosphere through air re-circulation. Therefore, respirable dust levels can be expected to increase with time during the shift, even at constant production levels. 7. A limited number of particle size analyses have indicated that there is no clear relationship between the dust concentration in mg/m3 and total surface area (m2) of the respirable dust sample. 8. For the first time, a clear delineation of coal types (semi-bituminous and semianthracite) that possess the most inherent respirable dust generation potential (IRDGP) was possible (p = 0.000). Also, there was no conclusive relationship (p = 0.373) between different semi-bituminous coal seams (1, 2, 4 and 5) and IRDGP. 9. The laboratory roll-crusher test results of South African coal types indicated that average inherent silica for the test coals was 3.54 %. The DELI model took into account, the merits of personal exposure data in exposure assessment, but the limitations and quality of data one obtains in the South African situation overweighed use of the fixed-point sampling. The “limits of acceptability” used in DELI are based upon acceptable guidelines prescribed by the authorities such as National Institute of Occupational Safety and Health (NIOSH), Mine Safety and Health Administration (MSHA), South African Department of Minerals and Energy Affairs (DME) and latest information on epidemiological studies. The DELI model gives the visual “colour” coding and descriptive categories for easy interpretation and understanding of exposed dust level to uneducated workforce. This type of DELI index representation gives a clear and concise picture of the mine or various section dust conditions. The DELI model exposure assessment technique gives accurate feedback because it was based on latest recommended size-selective sampling methods and instrument and vast amount of measured data, which was not previously available. The application of the developed DELI model for exposure assessment and its comparison with AQI were evaluated for coal mine dust data. The study demonstrated that the DELI model is a practical diagnostic tool that gives a fair reflection and information on dust levels and is an exposure assessment tool for the coal mining industry that will assist in reduction of CWP in South Africa.

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Liang, Lin Kung, and 林龔樑. "Study on Arsenic Exposure Hazard Prevention and Worker Health Index In Gallium-Arsenide(GaAs) Epitaxy Process." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/33890518156363751970.

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碩士
國立交通大學
產業安全與防災學程碩士班
91
This research studied the high technology companies with gallium arsenide process. questionnaires of 21 advanced technology companies with effective gallium arsenide manufacture capabilities were collected. The questionnaire investigation revealed that 62% of the advanced technology companies were established within 5 years, and 33% of the advanced technology companies were established within 10 years. Thus, 95% of the 21 advanced technology companies were newly formed. 93% of the gallium arsenide epitaxy production companies using metal organic chemical vapor deposition (MOCVD) machine to produce GaAs based Epitaxial layers. There was only one gallium arsenide epitaxy production company using the machines of molecular beam epitaxy and liquid phase epitaxy. It revealed that most gallium arsenide epitaxy production companies used MOCVD. These companies faced the problem of arsenic wastes treatment. Besides identification and classification of wastes, the most serious problem was these companies can not find the legal or qualified companies to deal with arsenic wastes in domestic area. No company can grind and recycle the wastes of gallium arsenide substrates. Therefore, majority of these companies store gallium arsenide substrates wastes in their factories, others commissioned foreign companies to recycle or solidify wastes. The reason for no recycling mechanism for rare gallium metals was probably due to no existing recycling company for gallium in Taiwan. This study also surveyed the workers exposed to arsenic in one advanced technology company which grows gallium arsenide epitaxyal layers. The study includes environmental monitoring for arsenic, and biological monitoring of arsenic. By using the Chi-Square test, the arsenic exposed workers group and the workers group with no arsenic exposure shows no significant differences no matter the age, working time, smoking status, alcohol consumption, diabetes, asthma, allergic rhinitis, allergic dermatitis, and kidney disease status. The total arsenic concentrations for samples collected from personal sampling and area sampling in the company were both lower than the permissible exposure limit of time weight average authorized by the Council of Labor Affairs, Executive Yuan. The total arsenic concentrations in air can not be correlated significantly with the trivalent arsenic concentration, pentavalent arsenic concentration, monomethylarsonic acid (MMA) concentration, dimethylarsinic acid (DMA) concentration, and total inorganic arsenic metabolites concentration, and the total arsenic concentration in hair, total arsenic concentrations in toenail, in urine. Howere, there was significantly positive correlation between the total arsenic concentrations in air and the total arsenic concentration in fingernail. Thus, the accumulation of low level arsenic exposure can’t be ignored. The maintenance personnel in the exposed arsenic enviroment should wear respirator, protective clothing, and protective glove, because the protective equipment is the last way to prevent exposure to the hazard arsenic enviroment.

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Pavlíková, Monika. "Výpočet expozičního indexu AOT40 z výsledků měření koncentrací přízemního ozonu pasivními dosimetry." Master's thesis, 2010. http://www.nusl.cz/ntk/nusl-296247.

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The study summerizes methods of ozone AOT40 index estimation from time intergarated passive sampler measurements in forests. Ground-level ozone is a highly phytotoxic atmospheric pollutant. In recent years negative impacts of elevated concentrations of ground-level ozone on vegetation and ecosystems have been studied and atmospheric levels of ozone have been measured. There is a noticeable negative impact of elevated concentrations of ground-level ozone on forests in the Czech Republic, mainly in rural areas that are far away from the emission sources. The AOT40F exposure index is a tool to assess the geographical areas with vegetation potentially at risk due to elevated ground-level ozone concentrations. The AOT40 index is the accumulated hourly exposure during daytime hours above cut-off concentration of 40 ppb, during the growing season. Passive samplers are used for measuring ground-level ozone in high spatial resolution. Passive samplers are easy to use. However this metod provides time intergrated values of pollutant concentrations (1-2 weeks). It is not possible to estimate AOT40 index by using just data of mean ozone concentrations over the sampling period. Three methods were used to estimate the exposure index AOT40F for forests by mean ozone concentrations measured in the Jizerské Hory...

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Hystad, Perry Wesley. "Modeling residential fine particulate matter infiltration : implications for exposure assessment." Thesis, 2007. http://hdl.handle.net/1828/1264.

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This research investigates the difference between indoor and outdoor residential fine particulate matter (PM2.5) and explores the feasibility of predicting residential PM2.5 infiltration for use in exposure assessments. Data were compiled from a previous study conducted in Seattle, Washington, USA and a new monitoring campaign was conducted in Victoria, British Columbia, Canada. Infiltration factors were then calculated from the indoor and outdoor monitoring data using a recursive mass balance model. A geographic information system (GIS) was created to collect data that could be used to predict residential PM2.5 infiltration. Spatial property assessment data (SPAD) were collected and formatted for both study areas, which provided detailed information on housing characteristics. Regression models were created based on SPAD and different meteorological and temporal variables. Results indicate that indoor PM2.5 is poorly correlated to outdoor PM2.5 due to indoor sources and significant variations in residential infiltration. A model based on a heating and non-heating season, and information on specific housing characteristics from SPAD was able to predict a large portion of the variation within residential infiltration. Such models hold promise for improving exposure assessment for ambient PM2.5.

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Federchook, Taylor Joan. "Recovery of DNA from teeth exposed to various temperatures." Thesis, 2017. https://hdl.handle.net/2144/26625.

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In situations of mass disaster (1), which include airline crashes (2), terrorist attacks (2), large fires (3), and mass homicide (4), the human remains are often damaged beyond recognition (5). In these cases, bones and teeth are potentially the only acceptable source of deoxyribonucleic acid, or DNA (6). Previous studies have evaluated a plethora of techniques to purify DNA from hard tissue, but there is no consensus on the optimal process by which to extract and purify DNA from these samples. Not only are hard tissue samples difficult to process, in many cases the samples are subjected to extreme environmental conditions, such as high temperature. Thus, there is interest in obtaining information on DNA quality from samples exposed to high temperatures (7). This work hopes to fill the gap by: 1) optimizing a DNA extraction protocol from hard tissue; and 2) measuring the degree to which the DNA is degraded in an effort to link the quantity and quality of the DNA recovered to the outer appearance of the tooth. To accomplish this, individual teeth were burned in a furnace at 100 °C, 200 °C, 300 °C, 400 °C, 500 °C, and 600 °C for 10, 20, and 30 minutes. The optimal extraction procedure utilized Amicon® Ultra-4 Centrifugal 30K filter devices and the QIAGEN MinElute Polymerase Chain Reaction (PCR) Purification Kit. Samples were quantified using the Quantifiler® Trio quantification kit to obtain the quantity and quality metrics. After heat exposure, each tooth was photographed and subsequently given a color designation or value: light yellow to beige teeth were assigned a value of 1; dark yellow to orange were assigned a value of 2; brown was assigned a value of 3; shiny black was assigned a value of 4; and black to light gray teeth were assigned a value of 5. Both carbonization and the early stages of calcination were observed. The mass of DNA per mass of tooth was determined by examining quantitative PCR (qPCR) results for both a large and small autosomal fragment. The degradation index, or DI, was also calculated from qPCR measurements. The results demonstrate a strong correlation between the quantity of DNA recovered, the quality of the DNA obtained, and the designated color value. The highest recovery rates were obtained from teeth assigned a color value of 1 (unaltered beige) or 2 (yellow to orange). These teeth were exposed to either room temperature, 100 °C or 200 °C. At temperatures exceeding 300 °C, the amount of DNA recovered drastically decreased and was inconsistent. Some of the samples subjected to temperatures at and above 300 °C resulted in no quantifiable DNA. In contrast, the DI results suggested that when the teeth were subjected to temperatures ≤ 100 °C, the quality of the DNA was good, wherein the DI value was approximately 1. At 200 °C, the temperature began to impact the DI value, which increased with time to the point where a DI was no longer able to be calculated because the large autosomal fragment could not be detected. In conclusion, the current work compares five different methods of DNA extraction to establish a best practice extraction procedure for these difficult samples. Furthermore, this work suggests that examination of the tooth’s appearance can be used to deduce whether successful DNA recovery is likely. In summary, the results demonstrate that when the tooth sample was assigned a color value of 1, the quantity and quality of the DNA obtained was high. Once the color value of the sample rose to 2, the quantity and quality of DNA varied greatly and the probative value of the sample was diminished. Samples that exhibited large color changes or had begun the calcination process resulted in no recoverable DNA.

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Munyai, Rendani Bigboy. "An assessment of community flood vulnerability and adaptation: A case study of Greater Tzaneen Local Municipality, South Africa." Diss., 2017. http://hdl.handle.net/11602/941.

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MENVSC (Geography)
Department of Geography and Geo-Information Sciences
The Limpopo lowveld is at risk of floods from tropical storms from the South West Indian Ocean. The flood risk is particularly high in low altitude areas with poor infrastructure and limited resources. This study assessed flood vulnerability and adaptation at Lenyenye, Ga-Kgapane Masakaneng and Nkowankowa Section B and C within the Mopani District in the Limpopo Province of South Africa. The research objectives were to establish the determinants of flood vulnerability, assess the levels of flood vulnerability and the community‟s coping strategies. A quantitative survey approach was employed using questionnaires which were administered to affected households to identify determinants of flood vulnerability, indicators and coping strategies by communities. A qualitative survey was also undertaken to supplement the information obtained from the quantitative survey. Key informant interviews were conducted with disaster management authorities in the study area to provide information on indicators, flood experience, adaptation and mitigation measures. Field observations were undertaken to observe the physical landscape and flood impacts. Secondary data were acquired through records, maps, Census 2011 and from the South African Weather Service. Collected data were imputed into the flood vulnerability index to measure the level of flood vulnerability. The results of this study will contribute to flood disaster risk reduction in the lowveld. The results indicate that flood vulnerability in the study areas is determined by dwelling quality, poor or lack of drainage, education levels, employment status, rainfall amount and topography. The calculated flood vulnerability levels in the three case study villages indicate that Ga-Kgapane Masakaneng, Lenyenye and Nkowankowa Section B and C have a „vulnerability to floods‟ level. However, the FVI also showed that the economic aspect scored a high vulnerability to floods in Ga-Kgapane. In Nkowankowa Section B and C; physical component obtained a „high vulnerability to floods.‟ Major coping strategies in the three case villages were: making „Le-guba‟ around houses; sand-bags; making a furrow and channel around houses and on roads; temporary relocation and lastly relocating to a safer area. Key recommendations are public awareness; integrating modern mitigations with local knowledge; development of programs to ensure resilience through incorporation of (Integrated Development Planning) IDP and flood management and flood early warning system.

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(5929760), Christelene A. Horton. "Lead Exposure and Effects across the Lifespan among Vulnerable Populations." Thesis, 2019.

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This dissertation examines lead exposure and effects across the lifespan among vulnerable populations. The vulnerable population that this dissertation focuses on are the elderly, newcomers to the US, which represents immigrants, as well as adolescents and women of childbearing age. The first chapter gives an introduction and highlights the history of lead as it relates to environmental and occupational exposure having deleterious effects on the human system. The second chapter highlights the association between blood lead level and subsequent Alzheimer’s disease (AD) mortality in those 65 years and older. Chapter 3 looks at whether length of time in the United States is a predictor of adolescent and adult blood lead levels. The fourth chapter assesses whether early life lead exposure is associated with AD mortality later in life. Adaptations of Chapter 2 and Chapter 3 of this dissertation have been submitted for publication.

Chapter 2 presents a longitudinal study of 8080 elders (≥60 years) with BLL data from the 1999-2008 National Health and Nutrition Examination Survey, where mortality was determined from linked 1999-2014 National Death Index data. In this study, a causal diagram presented causal assumptions and identified a sufficient set of confounders: age, sex, poverty, race/ethnicity, and smoking. Cox proportional hazard models were used to determine the association between BLL and subsequent AD mortality. Impacts of competing risks and design effect were also assessed. Adjusted hazard rate ratio (HRR) and 95% confidence interval (CI) were reported. Results showed that those with BLL of 1.5 μg/dL and 5 μg/dL had 1.2 (95% CI: 0.70, 2.1) and 1.4 (95% CI: 0.54, 3.8) times the rate of AD mortality compared to those with BLL of 0.3 μg/dL, respectively, after accounting for competing risks. Adjusted HRRs were 1.5 (95% CI 0.81, 2.9) and 2.1 (95% CI 0.70, 6.3), respectively, after considering design effect. This longitudinal study demonstrated a positive, albeit statistically non-significant association between BLL and AD mortality, after adjustment for competing risks or design effect.

Chapter 3 included cross-sectional 1580 women of childbearing age (15-45 years) and 5933 men and women (≥15 years) from the 2013-2016 United States National Health and Nutrition Examination Survey. Linear regression models adjusted for race/ethnicity, education, blood cotinine, age, sex (as appropriate) and accounted for complex survey design. Results showed that women of childbearing age who have lived 0-4 years in the US have, on average, a 43% (95% confidence interval (CI): 31%, 56%) higher BPb compared to women born in the US. Corresponding results for all adults and adolescents was 40% (95% CI: 28%, 51%). Similar, statistically significant, results were observed for other time periods (5-9 years, 10-19 years, and ≥20 years); the magnitude of the association decreased with increasing time in the US. Higher BPb was also significantly associated with Asian (vs. white), lower education, higher age, and male (vs. female).

Chapter 4 is an ecologic study utilizing data from the United States Census Bureau and American Fact Finder. This ecologic study uses publicly available data from the 1930s US census and the Centers for Disease Control and Prevention to compare estimated historic lead exposure with AD mortality rates among US states and Indiana counties. Occupations were assigned a numeric weight based on the likelihood of lead exposure. The proportion of workers in each occupation multiplied by this weight was used to create a historic lead exposure index; quintiles of this index were used in analyses. AD mortality rates among persons ≥ 65 years old from 1999-2016 were obtained from the Centers for Disease Control and Prevention. The relationship between the historic exposure index and mortality was evaluated using correlation coefficients and linear regression models adjusting for age, sex, education, socioeconomic status (SES). Maps to characterize spatial pattern of historic lead exposure and AD mortality were completed using Geographic Information System (GIS) spatial analysis tools for the U.S. at state level and at county level for Indiana. Results showed that among states, the average AD mortality rate was 202.2 per 100,000 (SD=44.4). Within Indiana, the average AD mortality rate was 209.6 per 100,000 (SD= 64.9). Among Indiana counties, the unadjusted model shows an association of higher HEI with higher AD mortality, with the fifth quintile reaching statistical significance. Results for the adjusted model were not statistically significant. Results for US states for both unadjusted and adjusted regression models show that the third, fourth, and fifth quintiles of the historic exposure index were associated with a significantly lower AD mortality rate when compared to the lowest quintile.

Conclusion: The first study, using a longitudinal design, shows a positive but non-significant association between BLL and subsequent AD mortality after adjustments for competing risks or design effects. The second study, using a cross-sectional design, showed that newcomers to the US may be a population at higher risk for elevated BPb. The third, ecological study, did not find any significant association between historic lead exposure and AD mortality rates for Indiana counties, however there was a significant association of higher historic lead exposure index with lower AD mortality rates for states in the US.

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LAI, YAN-LING, and 賴彥伶. "Investigation of Item Exposure Control and Constraint-weighted Item Selection of Continuous a-stratification Index in Computerized Adaptive Testing." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/aan383.

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碩士
國立中正大學
心理學系研究所
107
Because test takers can arrange the testing time according to their schedule, the former test takers might share the test information with the later ones. If test overlap rates between the former and later test takers were high, it could threaten test security and validity. Hence, item exposure control plays a critical role in computerized adaptive testing. A commonly used method for item exposure control is a-stratification. Whenever the item pool is updated frequently, it is inconvenient for practitioners to partition the item bank and determine appropriate strata. Huebner, Wang, Daly, and Pinkelman (2018) proposed the continuous a-stratification index (CAI), which incorporates exposure control as one building block intrinsic to the index itself, therefore having greater flexibility when applying in an operational framework. They found that when examinees come from the normal distribution, the CAI yielded 7% and 12% items overexposed for 20- and 30-item test length, respectively. It meant that the CAI still cannot control the item exposure rate well. Besides, assembling tests usually requires fulfilling various constraints, such as content balancing, key balancing, and so on; while composing a quiz should include all the constraints to avoid being dubious test validity. Previous researches adopted the maximum priority index (MPI; Cheng & Chang, 2009) to meet many constraints simultaneously; however, no research has been conducted to combine the CAI and MPI for item selection while meeting the constraints. The purpose of this paper has two fold: (a) to add the item exposure control method into the CAI for reducing the item exposure rates, and (b) to integrate the CAI with the MPI for item selection. Results show that after incorporating the CAI into the exposure control method, the item exposure rate was indeed effectively decreased, but the measurement precision slightly declined. When the CAI combined with the MPI, the item exposure and measurement precision were controlled well, while only a few constraints were violated.

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Soares, José Filipe Henriques. "Controlo automático de exposição (CAE) : dose no doente e qualidade de imagem." Master's thesis, 2012. http://hdl.handle.net/10400.14/10564.

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O controlo automático de exposição (CAE) é o sistema que suporta a definição dos parâmetros que vão conduzir a exposição e a dose no doente. Considerando que o circuito de medida é único e efectua o cálculo (e consequente corte) através da média do sinal recebido, sem ter em conta o gradiente de assimetria das densidades coincidentes com o campo dos respectivos detectores, formulou-se como objectivo o determinar a influência de diversas configurações do CAE na dose no doente e na qualidade da imagem num sistema de Radiologia Computadorizada (CR), em três regiões de um fantôma antropomórfico: tórax, abdómen e bacia. Seguiram-se os critérios recomendados por Guidelines internacionais e as imagens obtidas foram gravadas em Dicom e identificadas para posterior análise em software OsiriX. Os valores de cada exposição foram tratados no software Statistical Package for the Social Sciences (SPSS) e determinada a média, o desvio padrão, o erro padrão, a variância e realizado o teste de Tukey (HSD). No tórax, verificou-se que, utilizando o CAE direito se obtém menor dose absorvida no que noutras configurações: – 6,1% em relação ao esquerdo, – 39,7% do que quando se utiliza o central e de – 8,6% e de – 26,8% em relação à utilização dos dois laterais e aos três em simultâneo, respectivamente. No abdómen obteve-se a menor dose absorvida utilizando o CAE esquerdo: em relação ao direito de – 6,4%, em relação ao central de – 22,2%, em relação aos dois laterais e três em simultâneo de – 2,5% e de – 8,2%. Na bacia a menor dose absorvida foi obtida com a selecção do CAE central: tanto em relação a qualquer um dos laterais como dos três em simultâneo, com valores – 55,2% e – 30,8% respectivamente. Considerando uma prótese parcial na anca esquerda as diferenças acentuam-se em relação à selecção dos dois e dos três detectores em simultâneo para – 58,1% e – 30,1% e ao coincidente com a prótese de – 83,3%. Conclui-se que a importância dada à selecção do/s detector/es do CAE tem acção directa na redução da dose no doente, sem alterar a qualidade da imagem e que que as recomendações das Guidelines nem sempre estão de acordo com o Princípio da Optimização (Directiva 97/43 da Euratom). Os resultados obtidos indicam a necessidade de reapreciação das configurações do CAE sugeridas pela Dimond III e das European Guidelines o que poderá ser comprovado com um estudo relacionando os valores obtidos no fantôma com um cadáver, que se sugere como trabalho futuro.
The automatic exposure control (AEC) is the system that supports the definition of the parameters that will lead to exposure and dose to the patient. Whereas the measuring circuit system that is unique and is calculated (and consequent cutting) by averaging the received signal, without regard to the asymmetry of the density gradient coincident with the field of the respective exposure detectors, formulated as objective to determine the influence of various configurations of the EAC in the patient dose and image quality in a system of Computed Radiography (CR) in three regions of an anthropomorphic phantom: chest, abdomen and pelvis. Followed the criteria recommended by international Guidelines and the images were saved in Dicom and identified for further analysis in software OsiriX. The values for each exposure were treated in the Statistical Package for Social Sciences (SPSS) and determined the mean, standard deviation, standard error, variance and performed the Tukey test (HSD). In the thorax, it was found that, using the obtained lower right AEC absorbed dose in other configurations: – 6,1% on the left – 39,7% than when using the central and – 8,6% and – 26,8% compared to the use of two to three sides and at the same time, respectively. The abdomen was obtained using the lowest dose absorbed AEC left: on the right – 6,4%, relative to center – 22,2% on the two sides and three simultaneous – 2,5% and – 8,2%. In the lower bowl the absorbed dose was obtained by selection of AEC central, both in relation to any of the three sides and simultaneously, with values – 55,2% and – 30.8%, respectively. Whereas a partial prosthesis on the left hip accentuate differences in relation to the selection of the two and three detectors for simultaneously – 58,1% and – 30,1% and coincident with a value of the prosthesis – 83,3%. It is concluded that the importance given to the selection detector/s AEC has direct action in reducing the dose to the patient, without changing the image quality and that the recommendations of the Guidelines are not always in accordance with the Principle of Optimization (Directive 97/43 Euratom). The results indicate the need to review the settings suggested by AEC Dimond III and European Guidelines which can be proven with a study correlating the values obtained in the phantom with a corpse, which is suggested as future work.

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Mascarenhas, Caio Tentilhão. "Multi-criteria assessment to evaluate potential risk due to exposure to agrochemical products in natura 2000 sites of community importance in Italy." Master's thesis, 2018. http://hdl.handle.net/10362/33649.

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Dissertation submitted in partial fulfilment of the requirements for the degree of Master of Science in Geospatial Technologies
Natura 2000 network is the largest interconnected area of protected sites in the world and covers almost 20% of European Union territory. It entails more than 25.000 sites all over the 27 Member States (Sundseth, 2008). However, many protected areas consist of private lands where agricultural activities have impacts on the conservation of biodiversity and habitats. The spread of large amounts of synthetic agrochemical products, and the consequent contamination of ecosystems, can reduce the biodiversity, triggering selection processes and creating resistant strains to those substances (ISPRA, 2015). The present work is based on an embraced methodology to evaluate the potential risk from the use of agrochemical products in Natura 2000 Sites of Community Importance (SCI) in Italy. The methodology is founded on a multi-criteria assessment of several variables, combined to generate a simulated risk index. The aim of the project is to develop a replicable geoprocessing workflow to generate the potential Risk Index for SCI in Italy. The use of GIS analysis is addressed to perform an integrated multi-criteria calculation of potential risk, based on the Preliminary Risk Assessment Model for the identification and assessment of problem areas for Soil contamination in Europe (PRA.MS methodology). The potential Risk Index is an instrument based on a qualitative methodology, constructed from the expert judgment on certain variables. Despite being a qualitative method, the potential Risk Index is an indicator pointing to sites that are potentially in greater danger due to exposure to agrochemicals. Even though there is no “ground-truth” to validate the results, they may serve as a suggestion for further quantitative studies to be carried out in the areas of greatest risk.

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Setton, Eleanor May. "Probabilistic estimates of variability in exposure to traffic-related air pollution in the Greater Vancouver Regional District - a spatial perspective." Thesis, 2007. http://hdl.handle.net/1828/1195.

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A probabilistic spatial exposure simulation model (SESM) was designed to investigate the effect of time spent at work and commuting on estimates of chronic exposure to traffic-related air pollution in large populations. The model produces distributions of exposure estimates in six microenvironments (home indoor, work indoor, other indoor, outdoor, transit to work and transit other) for workers and non-workers, using randomly sampled time-activity patterns from the Canadian Human Activity Pattern Survey and work flow data from Statistics Canada. The SESM incorporates geographic detail through the use of property assessment data, shortest route analysis, and the use of a geographic information system (GIS) to develop pollution concentration distributions. The SESM was implemented and tested using data for 382 census tracts in the Greater Vancouver Regional District of British Columbia. Simulation results were found to be relatively insensitive to the choice of distance used to represent the typical range of non-work related trips; the use of a simple annual average pollution estimate versus a time-stratified annual average; and the use of different indoor/outdoor ratios representing the infiltration of ambient pollution into indoor locations. Substantial sensitivity was observed based on the use of different methods for producing spatial estimates of ambient air pollution. The SESM was used to explore variability in annual total exposure of workers to traffic-related nitrogen dioxide (NO2). Total exposure ranged from 8 μg/m3 to 35 μg/m3 of iv annual average hourly NO2 and was highest where ambient pollution levels are highest, reflecting the regional gradient of pollution in the study area and the relatively high percentage of time spent at home locations. Within census tract variation was observed in the partial exposure estimates associated with time spent at work locations, particularly in suburban areas where longer commuting distances are more prevalent. In these areas, some workers may have exposures 1.3 times higher than other workers residing in the same census tract. Exposures to NO2 associated with the activity of commuting to work were negligible. No statistically significant difference in total exposure estimates was found between female and male commuters, although there were small but observable differences at the upper end of the exposure distributions associated specifically with the work indoor microenvironment. These differences were highest in suburban areas (up to 3 μg/m3 of annual hourly average NO2 higher for female commuters, in relation to 99th percentile total exposures levels of approximately 37 μg/m3), illustrating the impact of systematically different work locations for female compared to male commuters in these same census tracts. Simulated exposures for workers, non-workers, and a base scenario where all time is spent at the residence only were compared. Statistically significant differences were found in the exposure distributions for workers versus non-workers, workers versus residence only, and non-workers versus residence only. Differences in exposure within census tracts were highest at the 10th and 90th percentiles, on the order of -5.4 to +6.5 μg/m3 of annual average hourly NO2 respectively for workers compared to non-workers, in relation to exposure estimates between 10 and 40 μg/m3 of annual average hourly NO2 on average.

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Sinkulová, Michaela. "Predikce průměrných hodinových koncentrací přízemního ozonu z měření pasivními dozimetry." Master's thesis, 2020. http://www.nusl.cz/ntk/nusl-436006.

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In terms of air pollution, ground-level ozone is according to current knowledge, contributes the most to damage to ecosystems. To calculate the key indicators of potential damage to ecosystems, such as the exposure index AOT40 and stomatal flux, it is important to know the hourly ozone concentrations, which are the input data for both calculations. For the measurement of O3 air pollution concentrations for the purposes of environmental studies, continuous measurement is not used, but measurement by passive (diffusion) dosimeters, which are exposed for a longer period (usually 1 week-1 month) and thus indicate the average concentration for the relevant longer period. The aim of this diploma thesis is the prediction of hourly concentrations of ground-level ozone from measurements by diffusive samplers, which took place in the period 2006-2010 in Jizerské hory mountains. Monitoring always took place for 2 weeks during the vegetation seasons (April-October) at localities and at various altitudes (714 m above sea level - 1,000 m above sea level). Ogawa diffusive samplers were used. From these average and meteorological concentrations, hourly values of ground-level ozone concentrations were calculated according to the model from professional study and these were compared with measurements from an...

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Hsiu, Chien Yi, and 簡伊琇. "The association between sister chromatid exchange, replication index in peripheral blood cells and cell cycle of exfoliated urothelial cells, and arsenic exposure among residents of Lanyang Basin." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/17812060733247635181.

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碩士
台北醫學院
公共衛生學研究所
86
Inorganic arsenic has been considered to be a human carcinogen. However, ther eis little evidence for its carcinogenicity in animal models. In vitro studie sshowed that it is also a potent clastogen in a variety of mammalian cellsyste ms. In this study, the spontaneous sister chromatid exchanges (SCEs) inhuman p eripheral blood cells, and the flow cytometric DNA ploidy of humanurothelial c ells were used to identify the early biological effects that mayreveal genetic damage by arsenic.Two villages, Meicheng and Meifu of Lanyang Basin located o n the northeastcoast of Taiwan, were selected as study area. Most of the resi dents in thisstudy area still drink well water. Well water in the two study v illages werefound to have variant arsenic contents, ranging from non-detected to 3,464 ug/Lin Meicheng and non-detected to 2,177 ug/L in Meifu, respectively . Arseniccontents in well water were divided into four groups, including non- detected to10, 10.1-50, 50.1-299.9, and 300 ug/L or more. A total of 80 resid ents wererecruited as study subjects. However, only 48 residents agreed to pa rticipatethis study. The number of study subjects in each groups is 11, 11, 1 4, 12,respectively. After adjustment for age, sex and cigarette smoking, SCEs in the group with arsenic contents in well water more then 50 ug/L was signifi cantly higher thanthat in the group less than 10 ug/L. The SCEs of cumulative arsenic exposuremore than 2,000 ug/L-year were significantly higher than that of cumulativearsenic exposure less than 2,000 ug/L-year. SCEs was not positi vely correlated with internal exposure indices included arsenic concentration in urine, arseniccontents in hair and toenail. The replication index (RI) of human peripheralblood cells was positively associated with arsenic contents in well water. Atotal of 43 samples for urothelial cell cycle analysis were inc luded in this study. After adjustment for age and sex, arsenic content in blo od was significantly associated with the indices of cell cycle such as values of G0G1,S and G2M. However, various arsenic exposure indices did not show an y significantly association with these indices of cell cycle. Furthermore,ars enic content in blood has negative association with G0G, and positiveassociati on with S and G2M, showing that inorganic arsenic might interfere thecell cycl e.

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Campbell, Jonathan Edward. "Exercise mediated changes in peripheral glucocorticoid exposure in the fructose-fed hamster /." 2006. http://proquest.umi.com/pqdweb?index=0&did=1299815841&SrchMode=1&sid=3&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1195667700&clientId=5220.

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Thesis (M.Sc.)--York University, 2006. Graduate Programme in Kinesiology and Health Science.
Typescript. Includes bibliographical references (leaves 50-71). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://proquest.umi.com/pqdweb?index=0&did=1299815841&SrchMode=1&sid=3&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1195667700&clientId=5220

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Lim, Jenny M. "Temporal effects of prenatal ethanol exposure on the hypothalamo-neurohypophyseal system in the rat (Rattus norvegicus)." Thesis, 2004. http://proquest.umi.com/pqdweb?index=0&did=775189191&SrchMode=1&sid=8&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1233884068&clientId=23440.

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Dissertations / Theses on the topic 'Exposure index'

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