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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
281

Variação de peso materno e fatores associados em diferentes ambientes intrauterinos

Cazarotto, Bianca da Rosa January 2017 (has links)
Introdução: Diferentes ambientes intrauterinos podem influenciar na variação de peso corporal materno pré-gestacional até seis meses após o parto. A variação de peso é um importante traço materno na direção do ganho de peso gestacional, uma vez que um ganho de peso insuficiente é relacionado ao parto prematuro, ao baixo peso ao nascer ou a um recém-nascido pequeno para a sua idade gestacional, enquanto o seu excesso está associado com o desenvolvimento de diabetes gestacional, parto prematuro, parto cesáreo, recém-nascidos grandes para a sua idade gestacional, retenção de peso materno e, consequentemente, sobrepeso e obesidade. Objetivo: Avaliar a variação do peso materno pré-gestacional até o sexto mês após o parto em puérperas de diferentes ambientes intrauterinos, verificando a associação de fatores sociodemográficos, obstétricos, nutricionais e comportamentais com este desfecho. Métodos: Trata-se de um estudo observacional longitudinal, utilizando uma amostra de conveniência de pares de mães e filhos divididos em quatro grupos: gestantes diabéticas (DM), hipertensas (HAS), tabagistas (TAB) e um grupo controle (CTL). A amostra foi recrutada em três hospitais públicos de Porto Alegre, capital do Rio Grande do Sul, no período de 2011 a 2016. Entrevistas domiciliares e no Centro de Pesquisa Clínica do Hospital de Clínicas de Porto Alegre foram realizadas para a coleta de dados. Foram coletadas informações de peso corporal materno, índice de massa corporal (IMC) pré-gestacional, ingestão alimentar, orientação nutricional durante a gestação e práticas de lactação como variáveis nutricionais-antropométricas; escolaridade materna, etnia, idade, renda familiar e estado civil, como variáveis sociodemográficas; planejamento da gestação, tipo de parto, número de consultas pré-natais e paridade como variáveis obstétricas e percepção de estresse, sintomas depressivos, e nível de atividade física durante a gestação, como variáveis comportamentais. As variáveis nutricionais-antropométricas, sociodemográficas e obstétricas foram coletadas por questionários estruturados. As variáveis comportamentais foram coletadas por meio de instrumentos validados (Escala de Estresse Percebido – 14, Escala de Depressão Pós-Parto de Edimburgo e Questionário Internacional de Atividade Física – versão curta). Regressões lineares múltiplas e modelos de estimativas generalizadas (GLMs) foram conduzidas para a identificação dos fatores associados à variação de peso materno 6 meses após o parto. Todas as análises foram realizadas no programa SPSS, versão 18.0, e o nível de significância adotado para todas as análises foi fixado em 5%, exceto para as comparações aos pares por GLMs, sendo estes em 10%. Resultados: A amostra foi composta de 124 puérperas distribuídas entre diferentes ambientes intrauterinos e um grupo controle. Para todas as GLMs, as medidas de peso materno foram ajustadas para algumas variáveis (estatura materna, paridade, escolaridade materna e tipo de parto), e foram fixadas 3 medições de tempo (peso pré-gestacional, peso antes do parto e 15 dias após o parto) para todas as análises. Os grupos DM e TAB apresentaram maior peso antes do parto, quando comparados com as demais medições. O grupo CTL apresentou maiores pesos 15 dias e 1 mês após o parto, enquanto o grupo HAS apresentou maior peso antes e 15 dias após o parto, em relação às outras avaliações. Um modelo hierárquico associou proximamente o diagnóstico materno de hipertensão arterial e o IMC pré-gestacional de sobrepeso com o ganho de peso materno aferido até o sexto mês após o parto (a diferença entre o peso materno ao sexto mês e o peso pré-gestacional). Já os IMCs pré-gestacionais maternos de desnutrição e de obesidade se associaram com a diminuição de peso corporal seis meses após o parto. Conclusões: Em uma população de diferentes ambientes intrauterinos verificou-se que o IMC de sobrepeso prégestacional e o diagnóstico de hipertensão arterial materna se relacionam com o aumento de peso corporal materno seis meses após o parto. / Introduction: Different intrauterine environments may influence maternal prepregnancy weight variation up to six months after delivery. Gestational weight gain has important maternal-infant repercussions, affecting outcomes of pregnancy and delivery. Insufficient weight gain is related to preterm birth, low birth weight and to newborns small for their gestational age, while its excess is associated with the development of gestational diabetes, preterm delivery, cesarean delivery, newborns large for their gestational age, maternal postpartum weight retention and, consequently, overweight and maternal obesity. Aim: To evaluate the prepregnancy weight gain up to the sixth month after delivery in mothers from different intrauterine environments, verifying its association with sociodemographic, obstetric, nutritional and behavioral factors. Methods: This was a longitudinal observational study, using a convenience sample of mothers and children divided according to four groups of pregnant women: diabetic (DM), hypertensive (HM), smokers (SM), and control (CM) women. The sample was recruited from three public hospitals in Porto Alegre, capital of Rio Grande do Sul, from 2011 to 2016, and the interviews were home conducted or at the Clinical Research Center of the Clinical Hospital of Porto Alegre. Data collection included information on maternal body weight, prepregnancy body mass index (BMI), food intake, nutritional orientation during gestation and lactation practices as nutritionalanthropometric variables; maternal educational level, ethnicity, age, family income and marital status as sociodemographic variables; gestation planning, type of delivery, number of antenatal care visits and parity as obstetric variables; and perceived stress, depressive symptoms, and physical activity level during gestation as behavioral variables. The sociodemographic, nutritional, anthropometric and obstetric variables were collected by structured questionnaires, and the behavioral ones by validated instruments (Perceived Stress Scale – 14, Edinburgh Postpartum Depression Scale, and the International Physical Activity Questionnaire – short version). Multiple linear regressions and Generalized estimates models (GLMs) were conducted to identify factors associated with maternal weight variation up to six months after delivery. The significance level adopted for all analyzes was set at 5%, except for the pairwise comparisons by GLMs, which were set at 10%. All analyzes were performed in the SPSS, version 18.0. Results: The samples consisted of 124 mothers distributed among the four different intrauterine environments. For all GLMs analyzes, maternal weight measures were adjusted for some variables (maternal height, parity, educational level and the type of delivery) and 3 measurements were fixed (prepregnancy, preceding delivery, and 15 days weight after delivery). The DM and SM groups presented greater weight preceding delivery when compared with all other measurements. The CM group displayed higher weights 15 days and 1 month after delivery, while the HM group presented higher weight 15 days after delivery, in relation to other evaluations. A hierarchical model associated maternal diagnosis of hypertension and prepregnancy BMI of overweight with maternal weight gain measured up to the sixth month after delivery (the difference between maternal weight at 6 months and prepregnancy weight). Maternal prepregnancy BMIs of malnutrition and obesity were associated with a decrease in body weight gain six months after childbirth. Conclusions: In a population of different intrauterine environments, it was verified that the prepregnancy overweight BMI and the diagnosis of maternal hypertension were related to maternal body weight gain six months after delivery.
282

Visual ecology of nocturnal bees: how light intensity affects foraging activity in cambuci, a neotropical Myrtaceae / Ecologia Visual de Abelhas Noturnas: como a intensidade de luz afeta a atividade de forrageio no cambuci, uma Myrtaceae neotropical

Dias, Rodolfo Liporoni 02 May 2018 (has links)
The foraging activity of day-active bees often rely on flower availability, light intensity and temperature. However, some bees developed a nocturnal habit and fly during the dusk, dawn and night. We still do not know how these bees cope with environmental factors, especially dimmer light levels, to explore flower earlier than their diurnal relatives. Given that typical bee apposition compound eyes work better in brighter environments and function in their limits in dim-light conditions, we can expect a larger dependence of light intensity for nocturnal groups. Nocturnal and crepuscular bees are frequent visitors of cambuci (Campomanesia phaea, Myrtaceae) in southeastern Brazil. We aimed to investigate how light intensity affects flower visitation of cambuci by nocturnal and crepuscular bees, also controlling for other environmental factors. We counted visits per minute along 30 nights/twilights in 33 cambuci trees from a commercial orchard, measuring the following environmental variables: light intensity, flower availability, temperature, air relative humidity and wind speed. Light intensity is the only variable that explained flower visitation of nocturnal bees in cambuci, which peaks at intermediate light levels that occur around 30 minutes before sunrise. The minimum light intensity threshold to bees start flying is of 0.00024 cd/m2, the first recorded value for nocturnal and crepuscular bees finding flowers in an agro-forest context. Our results highlight for the first time how nocturnal bees rely on light to explore resources and show that the bees light-dependent foraging activity is not always linear, as postulated by previous theoretic models. This is the first step to understand how nocturnal bees react to environmental factors. Our findings also bring concerns about possible negative effects of light pollution at night for cambuci-crepuscular bees interaction / O forrageio de abelhas geralmente depende de disponibilidade de flores, intensidade de luz e temperatura. Contudo, algumas abelhas desenvolveram hábitos noturnos e voam durante os crepúsculos e a noite. Não se sabe como essas abelhas lidam com os fatores ambientais, especialmente os reduzidos níveis de luminosidade. Dado que os olhos compostos de aposição de abelhas funcionam melhor em maiores luminosidades, espera-se uma maior dependência da luz para os grupos noturnos. Abelhas noturnas e crepusculares são visitantes frequentes do cambuci (Campomanesia phaea, Myrtaceae) no sudeste do Brasil. Nosso objetivo foi investigar como a intensidade de luz afeta a visitação floral do cambuci por abelhas noturnas e crepusculares, controlada também por outros fatores ambientais. Para isso, contamos as visitas a cada minuto ao longo de 30 noites/crepúsculos em 33 árvores de cambuci em um pomar comercial, medindo as seguintes variáveis ambientais: intensidade de luz, disponibilidade de flores, temperatura, umidade e velocidade do vento. A intensidade de luz foi a única variável que explicou a visitação floral de abelhas noturnas no cambuci, a qual tem um pico em níveis intermediários de luz que ocorrem ao redor de 30 minutos antes do nascer do sol. O limiar mínimo de intensidade de luz para as abelhas começarem a voar foi de 0.00024 cd/m2, o primeiro valor registrado para abelhas noturnas e crepusculares procurando por flores em um contexto agroflorestal. Nossos resultados destacam pela primeira vez como as abelhas noturnas dependem da luz para explorar recursos e mostram que essa dependência, para abelhas em geral, não é sempre linear, como postulado por modelos teóricos prévios. Este é o primeiro passo para entender como abelhas noturnas reagem a fatores ambientais. Nossos dados também trazem alertas para possíveis efeitos negativos da poluição luminosa à noite para a interação entre cambuci e abelhas noturnas
283

Estratégias reprodutivas e ecologia alimentar de serpentes aquáticas da tribo Hydropsini (Dipsadidae, Xenodontinae). / Reproductive strategies and feeding ecology of the aquatic snakes of the tribe Hydropsini (Dipsadidae, Xenodontinae).

Scartozzoni, Rodrigo Roveri 27 January 2010 (has links)
A tribo Hydropsini compreende três gêneros de serpentes. Dados alimentares são escassos, mas indicam que as espécies consomem principalmente peixes e secundariamente anfíbios anuros. Os Hydropsini são ovíparos ou vivíparos e o polimorfismo é sugerido para algumas espécies. Entretanto, outros aspectos reprodutivos são desconhecidos para a maioria dessas serpentes. Por outro lado, as relações filogenéticas entre os Hydropsini estão estabelecidas. Este trabalho teve como objetivo caracterizar a reprodução e alimentação de doze espécies dos três gêneros, mapear a evolução e analisar possíveis relações entre a evolução de caracteres morfológicos, reprodutivos e alimentares, utilizando a filogenia disponível. Dados foram obtidos de indivíduos preservados (N = 2.871) de espécies amazônicas (Hydrops spp., Pseudoeryx spp., Helicops hagmanni, H trivittatus, H angulatus, H polylepis), do sudoeste (H leopardinus) e sudeste do Brasil (H carinicaudus, H modestus, H infrataeniatus, H gomesi). Os Hydropsini são especialistas em peixes, porém algumas Helicops (exceto H hagmanni) podem consumir anfíbios e lagartos. Hydrops triangularis e P. plicatilis são especialistas em peixes alongados (Synbranchiformes), Peixes Gymnotiformes, Siluriformes e Perciformes foram dominantes nas dietas de Hy. martii, H polylepis e H hagmanni, respectivamente. Nenhum tipo de presa teve dominância importante nas dietas das demais espécies, porém Perciformes foram consumidos com maior freqüência pela maioria. Esses dados indicam que as espécies diferem quanto ao local de forrageio. Aparentemente, o ancestral da tribo possuía cabeça pequena e dieta composta por Synbranchiformes. A dieta se toma mais ampla e o tamanho da cabeça parece ter aumento no ancestral de Helicops. As presas consumidas por muitas Helicops possuem corpos relativamente mais altos e são mais robustas o que pode explicar alterações no crânio de determinadas espécies. Fêmeas atingem a maturidade com tamanho, relativo ao tamanho médio dos adultos, similar em comparação aos machos. Fêmeas são maiores, possuem maior cabeça, circunferência e cauda mais curta que machos. O menor tamanho dos machos indica que o ritual de combate não deve ocorrer na tribo. Os Hydropsini são ovíparos ou vivíparos e o polimorfismo foi confirmado para H angulatus. A reprodução da maioria das espécies deve ser bienal, já que menos de 50% das fêmeas estavam reprodutivas. Os ciclos das fêmeas são sazonais, exceto para H angulatus. A reprodução das espécies amazônicas ocorre ao longo da estação seca e parte da chuvosa. Ciclos reprodutivos restritos às chuvas ocorrem para as espécies do sudeste e sudoeste. Diferenças nos ciclos das fêmeas podem estar associadas à variação no clima dessas regiões. A espermatogênese pode ser contínua ou sazonal. Os duetos deferentes de muitas espécies estão maiores na seca, sugerindo a ocorrência de cópula nesta estação. A fecundidade e o tamanho dos filhotes, relativos ao tamanho das fêmeas, não diferiu entre serpentes ovíparas e vivíparas. A oviparidade é característica plesiomórfica e a viviparidade pode ter surgido três vezes entre as Helicops. A fecundidade parece aumentar no ancestral do clado (Pseudoeryx, Helicops), o qual é composto por serpentes mais robustas em comparação a Hydrops e a muitos Xenodontinae. Porém, o tamanho dos filhotes tende a diminuir nessas serpentes. / The tribe Hydropsini comprises three genera of snakes. Information on food habits is scarce. However previous data indicate that species feed mainly upon fishes but also eat anurans. The Hydropsini are oviparous or viviparous and the polymorphism is suggested for some species. Other reproductive traits are unknown for most species. On the other hand, the phylogenetic relationships of Hydropsini are established. This study aimed to characterize the reproduction and the feeding habits of twelve species of three genera, hypothesise the evolution of morphological, reproductive and diet characters, as well as probable relationships among these traits. Data were obtained from preserved individuals (N = 2.871) of species from northern (Hydrops sp., Pseudoeryx sp., Helicops hagmanni, H. trivittatus, H. angulatus, H. polylepis), southwestern (H. leopardinus) and southeastern Brazil (H. carinicaudus, H. modestus, H. infrataeniatus, H. gomesi). The Hydropsini feed on fishes, but most Helicops eat also frogs and eventually lizards. Hydrops triangularis and P. plicatilis are specialized on Synbranchiformes fishes. Siluriformes, Perciformes and Gymnotiformes were the dominant item in of H. polylepis, H. hagmanni and Hy. martii, respectively. Other species eat several fishes, but Perciformes were consumed more frequently by most. These data here obtained suggest that the species differ in foraging microhabitat. The ancestor of the tribe probably had small head and diet composed predominantly by Synbranchiformes. The diet became widespread and the size of the head increase in the ancestor of Helicops. The preys consumed by most Helicops are stouter and have higher bodies, which may explain changes in the skull of some species. Females and males attain sexual maturity at similar body size, but adult females are larger. Moreover females have larger head and body circumference, and shorter tail than males. The smaller size of males indicates that the combat behavior should not occur in the tribe. The Hydropsini are oviparous or viviparous and the polymorphism was confirmed to H. angulatus. The reproduction of most species may be biennial, since less than 50% of females were reproductive. The cycles of females are seasonal. At the least H. angulatus, has continuous cycle. The reproduction of the Amazonian species occurs throughout the dry season and part of the rainy season. Cycles restricted mainly to the rainy season occur for species in southeastern and southwestern. Differences in the females cycles may be related to distinct climate in the occurrence areas of the species. The spermatogenesis are continuous or seasonal (restricted to the dry or rainy season). The diameter of deferent ducts of most species are larger in the dry season, suggesting that mating is restricted to this season. The fecundity and size of newborns, relative to the body size of female, was similar among species and did not differ between oviparous and viviparous snakes. The oviparity is plesiomorphic and the viviparity may have arisen at the least three times among Helicops. The fecundity increases in the ancestor of the clade (Pseudoeryx, Helicops), which is stouter than Hydrops and many Xenodontinae. However, the size of newborns tends to decrease in these snakes.
284

Authenticating & repairing personhood : the experiences of opioid dependent back pain sufferers

Gardner, Janet Rose January 2003 (has links)
Abstract not available
285

Pro-environmental travel behavior : The importance of attitudinal factors, habits, and transport policy measures

Eriksson, Louise January 2008 (has links)
The aim of this thesis was to study determinants of a readiness for pro-environmental travel behavior in households. Four empirical studies were conducted examining reduction in car use (Study I), acceptability of transport policy measures (Study II and III), and behavioral adaptations in response to travel demand management (TDM) measures (Study IV). In Study I, the aim was to interrupt habitual car use by means of a deliberation intervention and to examine the importance of moral motivation (i.e., personal norm) for car use reduction. Results showed that, as a result of the intervention, car use was mainly reduced among car users with a strong car use habit and a strong moral motivation to reduce car use. The aim of Study II was to examine factors important for the acceptability of three TDM measures: raised tax on fossil fuel, improved public transport, and an information campaign. The results demonstrated the importance of general environmental beliefs (i.e., pro-environmental orientation, problem awareness, personal norm, and willingness to reduce car use) and policy specific beliefs (i.e., perceived impact on freedom to choose travel mode and own car use, perceived effectiveness, and perceived fairness) for the acceptability of the measures. Furthermore, personal norm was found to be particularly important for the acceptability of raised tax and the information campaign, whereas problem awareness was more important for the acceptability of improved public transport. Following up on Study II, the purpose of Study III was to examine the acceptability of single and combined transport policy measures, more specifically, raised tax on fossil fuel, improved public transport, subsidies of renewable fuel, a package of raised tax on fossil fuel and improved public transport, and a package of raised tax on fossil fuel and subsidies of renewable fuel. General environmental beliefs (i.e., pro-environmental orientation, problem awareness, personal norm, and willingness to act) and policy specific beliefs (i.e., perceived effectiveness and perceived fairness) were found to be important for the acceptability of the measures. Moreover, personal norm was particularly important for the acceptability of raised tax on fossil fuel and the packages, while problem awareness was more important for the acceptability of improved public transport and subsidies of renewable fuel. The aim of Study IV was to examine the behavioral adaptations, more specifically, the expected car use reduction, in response to three hypothetical TDM measures: raised tax on fossil fuel, improved public transport, and a package of raised tax on fossil fuel and improved public transport. Furthermore, factors important for the expected car use reduction were analyzed. Results showed that a combination of the measures was expected to lead to a larger car use reduction compared to the single measures, and the most commonly chosen reduction strategies were more efficient car use and changing travel mode. Moreover, internal motivational factors, such as personal norm, and the perceived personal impact of the measures were important for expected car use reduction in response to the measures.
286

The Practice of Voting: Immigrant Turnout, the Persistence of Origin Effects, and the Nature, Formation and Transmission of Political Habit

Pikkov, Deanna 11 January 2012 (has links)
This dissertation is a multi-layered examination of the practice of voting, with a focus on the electoral turnout of immigrants. Chapter Two’s statistical analyses show that pre-migration cultural familiarity with democracy, formalized as levels of democratization in source countries, strongly shapes the likelihood of post-migration voting among Canadian immigrants. These origin effects, comparable in size to the best predictors of turnout that we have, exert a persistent influence – affecting turnout not only among the foreign-born, but also among the native-born second generation. Multilevel models demonstrate that the shifting source country composition of immigrant period-of-arrival cohorts provides an alternate explanation for what have previously been identified as generational, racial, and length of residence or ‘exposure’ effects among immigrant voters. This provides further evidence that voting is in most cases habitual, and raises questions about the acquisition, transmission, and reproduction of a voting practice. Chapter Three’s narratives of political development, gathered through in-depth, semi-structured interviews, confirm the importance of parental influence, and suggest that the ‘stickiness’ of practical capacities like voting may be the result of powerful processes of observational social learning. Providing a new twist on dominant models of political socialization, observation of parental voting appears to be the pivotal event in a path-dependent process of political learning, with acquisition of values and beliefs playing a supporting, rather than a leading role. Chapter Four reviews recent efforts among sociologists to amend action theory to make more room for habit, and these efforts are discussed in reference to contemporary research on turnout. I argue that these theoretical revisions still retain too sharp a focus on the cognitive aspects of practice. There is a lack of appreciation for the ways that action itself – our own previous actions and the actions of those close to us – can directly structure outcomes. Evidence from cognitive neuroscience is used to more precisely delineate habitual behaviour and thought. Where the intergenerational transmission of voting behaviour is concerned, culture is often coded directly into embodied practice. Efforts to encourage electoral participation should be built on a better understanding of voting’s substantial behavioural aspects.
287

The Practice of Voting: Immigrant Turnout, the Persistence of Origin Effects, and the Nature, Formation and Transmission of Political Habit

Pikkov, Deanna 11 January 2012 (has links)
This dissertation is a multi-layered examination of the practice of voting, with a focus on the electoral turnout of immigrants. Chapter Two’s statistical analyses show that pre-migration cultural familiarity with democracy, formalized as levels of democratization in source countries, strongly shapes the likelihood of post-migration voting among Canadian immigrants. These origin effects, comparable in size to the best predictors of turnout that we have, exert a persistent influence – affecting turnout not only among the foreign-born, but also among the native-born second generation. Multilevel models demonstrate that the shifting source country composition of immigrant period-of-arrival cohorts provides an alternate explanation for what have previously been identified as generational, racial, and length of residence or ‘exposure’ effects among immigrant voters. This provides further evidence that voting is in most cases habitual, and raises questions about the acquisition, transmission, and reproduction of a voting practice. Chapter Three’s narratives of political development, gathered through in-depth, semi-structured interviews, confirm the importance of parental influence, and suggest that the ‘stickiness’ of practical capacities like voting may be the result of powerful processes of observational social learning. Providing a new twist on dominant models of political socialization, observation of parental voting appears to be the pivotal event in a path-dependent process of political learning, with acquisition of values and beliefs playing a supporting, rather than a leading role. Chapter Four reviews recent efforts among sociologists to amend action theory to make more room for habit, and these efforts are discussed in reference to contemporary research on turnout. I argue that these theoretical revisions still retain too sharp a focus on the cognitive aspects of practice. There is a lack of appreciation for the ways that action itself – our own previous actions and the actions of those close to us – can directly structure outcomes. Evidence from cognitive neuroscience is used to more precisely delineate habitual behaviour and thought. Where the intergenerational transmission of voting behaviour is concerned, culture is often coded directly into embodied practice. Efforts to encourage electoral participation should be built on a better understanding of voting’s substantial behavioural aspects.
288

Experiential Avoidance in Chronic Tic Disorders: an Online Survey and Pilot Treatment Study Using Habit Reversal and Acceptance and Commitment Therapy

Best, Stephanie Helena January 2009 (has links)
<p>Among some researchers, there is an emerging conceptualization of chronic tic disorders (CTDs) as conditions that are partially rooted in avoidance of tic-related private experiences (i.e., painful or difficult thoughts and feelings) and internal sensations (i.e., premonitory urges to tic). The first specific aim of the present research was to investigate the possibility that experiential avoidance is related to tic severity and perceived quality of life in individuals with CTDs. The second aim was to determine whether the efficacy of Habit Reversal Training (HRT), the most prevalent and effective behavioral intervention for CTDs to date, might be enhanced by combining it with Acceptance and Commitment Therapy (ACT), an intervention that directly targets experiential avoidance. These aims were addressed by conducting two related studies. Study I, an online survey, included 239 adults (<italic>M</italic> = 37.6 years; <italic>SD</italic> = 13.8 years) who reported having been previously diagnosed with a CTD. Results showed that levels of premonitory urges, as well as both general and tic-specific experiential avoidance, were significantly positively related to tic severity. General and tic-specific experiential avoidance were also significantly negatively related to perceived quality of life. Psychometric analyses of two novel measures developed for Study I (i.e., the Yale Global Tic Severity Scale-Self-Report Version and the Acceptance and Action Questionnaire-Tic-Specific Version) demonstrated excellent internal consistency and convergent validity. Study II, a multi-site pilot investigation, involved 13 adolescents (<italic>M</italic> = 15.4 years; <italic>SD</italic> = 1.3 years) who were treated with either HRT alone or a novel HRT+ACT intervention. Results suggest that the HRT+ACT treatment is feasible, highly acceptable to both patients and parents, and as effective as HRT alone at reducing tic severity from pre-treatment through week 22 follow-up. Participants in both groups reported clinically significant post-treatment decreases in general and tic-specific experiential avoidance and improvements in overall functioning. Researchers concluded that experiential avoidance plays an important role in tic expression and overall functioning for individuals with CTDs. Results support additional development and testing of the promising HRT+ACT intervention, to evaluate its efficacy alone and in comparison to other relevant psychosocial and pharmacological interventions.</p> / Dissertation
289

Essays in asset pricing and portfolio choice

Illeditsch, Philipp Karl 15 May 2009 (has links)
In the first essay, I decompose inflation risk into (i) a part that is correlated with real returns on the market portfolio and factors that determine investor’s preferences and investment opportunities and (ii) a residual part. I show that only the first part earns a risk premium. All nominal Treasury bonds, including the nominal money-market account, are equally exposed to the residual part except inflation-protected Treasury bonds, which provide a means to hedge it. Every investor should put 100% of his wealth in the market portfolio and inflation-protected Treasury bonds and hold a zero-investment portfolio of nominal Treasury bonds and the nominal money market account. In the second essay, I solve the dynamic asset allocation problem of finite lived, constant relative risk averse investors who face inflation risk and can invest in cash, nominal bonds, equity, and inflation-protected bonds when the investment opportunityset is determined by the expected inflation rate. I estimate the model with nominal bond, inflation, and stock market data and show that if expected inflation increases, then investors should substitute inflation-protected bonds for stocks and they should borrow cash to buy long-term nominal bonds. In the lastessay, I discuss how heterogeneity in preferences among investors withexternal non-addictive habit forming preferences affects the equilibrium nominal term structure of interest rates in a pure continuous time exchange economy and complete securities markets. Aggregate real consumption growth and inflation are exogenously specified and contain stochastic components thataffect their means andvolatilities. There are two classes of investors who have external habit forming preferences and different localcurvatures oftheir utility functions. The effects of time varying risk aversion and different inflation regimes on the nominal short rate and the nominal market price of risk are explored, and simple formulas for nominal bonds, real bonds, and inflation risk premia that can be numerically evaluated using Monte Carlo simulation techniques are provided.
290

A Different Approach To Evolutionary Ethics: From Biology To Society

Aydin, Aysun 01 February 2008 (has links) (PDF)
In this thesis I analyze the evolutionary ethics and propose a new perspective that develops on the notion of altruism. The view of evolutionary ethics, especially the sociobiological account, has some problems. The most important philosophical problem is the &ldquo / is-ought&rdquo / problem which refers to the question as to whether moral propositions can be inferred from factual statements. In order to overcome this problem I suggest a different reading of the notion of altruism namely &ldquo / altruistic behavior practice&rdquo / that refers to norms, habits and repeated actions that provide the sustainability of society. The notion of altruistic behavior practice is presented and evaluated with the help of Alasdair MacIntyre&rsquo / s and John Dewey&rsquo / s moral philosophy. The moral views of these two philosophers are based on human practices and habitual formations in society. In this respect, evolutionary ethics and the notion of altruism are re-established on the basis of human practices and habitual modes of socialization.

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