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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.
41

Modelo teórico sobre os significados do estresse precoce e a vida adulta com depressão / Theoretical model of the meanings of early life stress and adulthood with depression

Carla Araujo Bastos Teixeira 22 February 2017 (has links)
O desenvolvimento humano, presente desde a formação primária do indivíduo é constituído pelo conjunto das experiências vividas durante infância, incluindo as experiências de estresse precoce. Tais vivências repercutem nas ações do sujeito, podendo ser importante no aparecimento da depressão. Objetivos: explorar e analisar o significado do Estresse Precoce para portadores de depressão e construir um modelo teórico sobre o fenômeno estudado; caracterizar a amostra quanto às características sociodemográficas e de saúde; explorar e analisar, à luz do Interacionismo Simbólico, o significado do estresse precoce entre adultos portadores de depressão. Método: Estudo qualitativo que teve como referencial teórico norteador o Interacionismo Simbólico e como referencial metodológico a Teoria Fundamentada nos Dados. Os participantes desse estudo foram portadores de depressão que vivenciaram Estresse Precoce, recrutados no Centro de Atenção Psicossocial - CAPS III do interior paulista. Instrumentos utilizados: Childhood Trauma Questionnaire -CTQ, questionário sociodemográfico e entrevista em profundidade. O número de participantes foi se configurando conforme a análise da teoria emergente (amostragem teórica), totalizando 12 participantes. Resultados: a análise dos dados permitiu identificar o modelo teórico \"Caminhando entre a infância traumática e a vida adulta com depressão\". Sete categorias estruturaram a experiência relatada pelos participantes do estudo: \"Vivenciando o Estresse Precoce\"; \"Sentindo diferenciação de tratamento dentro no núcleo familiar\"; \"Percebendo a distribuição de papeis dentro do núcleo familiar\"; \"Construindo a si próprio\"; \"Aliando-se à passividade frente a incapacidade de decisões\"; \"Percebendo comportamentos nos pais e em si próprio\" e \"Vivenciando a depressão\". Conclusões: o estudo permitiu identificar um modelo teórico que simbolizou a forma como as vivências foram compreendidas pelos próprios sujeitos e como o significado de cada experiência foi se entrelaçando na composição do ser, moldando seu conjunto de símbolos, sendo expresso em sentimentos, percepções e comportamentos. O modelo teórico contribuiu para a compreensão dos significados construídos e as condições que afetam o indivíduo desde a infância traumática até a depressão na idade adulta / Human development, present since the primary formation of the individual, consists of all the lived experiences during childhood, including the early life stress experiences. Such experiences have repercussions on the subject actions, and may be important in the depression onset. Objectives: To explore and to analyze the meaning of early life stress in adulthood with depression and to construct a theoretical model about the phenomenon; To characterize the sample regarding sociodemographic and health characteristics; to explore and to analyze, in the according to Symbolic Interactionism, the meaning of early life stress among adults with depression. Method: Qualitative study that had as a guiding theoretical referential the Symbolic Interactionism and Grounded Theory as a methodological referential. The study participants were depressive individuals who experienced early life stress, recruited at the Center for Psychosocial Care - CAPS III in inner city of São Paulo, Brazil. Instruments: Childhood Trauma Questionnaire - CTQ, sociodemographic questionnaire and in-depth interview. The participants number was configured according to the analysis of the emerging theory (theoretical sampling), totaling 12 participants. Results: Data analysis allowed the identification of the theoretical model \"Walking between traumatic childhood and adulthood with depression\". Seven categories structures the experience: \"Experiencing early life stress\"; \"Feeling treatment differentiation within the family nucleus\"; \"Perceiving the distribution of characters within the family\"; \"Building Yourself\"; \"Allying to passivity in the face of inability to make decisions\"; \"Perceiving behaviors in parents and in yorurself\" and \"Experiencing depression\". Conclusions: the study allowed to identify a theoretical model that symbolized the way as the experiences were understood by the individuals and how the meaning of each experience was interlaced in the composition of being, shaping its set of symbols, being expressed in feelings, perceptions and behaviors. The theoretical model contributed to the understanding of the raised meanings and the conditions that affect the individual from traumatic childhood to depression in adulthood
42

Effects of effluent wastewater in developing zebrafish (Danio rerio)

Frieberg, Kim January 2018 (has links)
Traditional wastewater treatment is known not to be specifically designed to eliminate the new generation of chemical residues that ends up in the sewage system. Polluted wastewatereffluent therefore reaches the aquatic environment possibly causing adverse effects in aquatic wildlife. The effects of effluent water from five Swedish sewage treatment plants sampled on 6 occasions 2017, were studied in developing zebrafish (Danio rerio). The study included morphological, physiological and behavioural endpoints. Overall there were few effectswhere deviations from control animals could be seen in the exposed zebrafish. The overall outcome of this assessment was that the wastewater effluent had no consistent effects on the early development of zebrafish. The consequences of continuous low-level exposure duringthe whole life-cycle of wild fish are presently unknown and further studies are needed to evaluate potential risks.
43

Faunal Composition and Distribution of Pelagic Larval and Juvenile Flatfishes (Teleostei: Pleuronectiformes) in the Northern Gulf of Mexico: Connectivity Between Coastal and Oceanic Epipelagic Ecosystems

Malarky, Lacey 08 December 2015 (has links)
Pleuronectiformes (flatfishes) occur throughout the global oceans, and have high ecological and commercial importance in some areas. Though much is known regarding life history, abundance, and distribution for the benthic adult stage of flatfish species, much less is known about the pelagic larval phases of flatfishes in the open ocean. Taxonomic uncertainty and limited sampling in the oceanic Gulf of Mexico contribute to data gaps with respect to the distribution of early life history stage of flatfishes in this region. Knowledge of the faunal composition, abundance and distribution of larval flatfishes, such as members of Bothus, which have extended pelagic phases, is important for modeling their population dynamics as well as for understanding the importance of connectivity between neritic and oceanic ecosystems in their life histories. Pleuronectiform specimens utilized in this study were collected in the northern offshore Gulf of Mexico during several cruises conducted throughout 2010-2011 as part of the NOAA Natural Resource Damage Assessment (NRDA) after the Deepwater Horizon Oil Spill (DWHOS). The Offshore Nekton Sampling and Analysis program (ONSAP) was established to determine composition, abundance and distribution of deep-water invertebrates and fishes in Gulf of Mexico waters that were potentially affected by the DWHOS. Results of the first large-scale discrete-depth distributional analysis of fishes in this region revealed that flatfishes were an intrinsic component of the oceanic ichthyofauna of these waters. A total of 2365 flatfish specimens were collected in offshore waters, representing four families and 11 of the 18 genera that occur in the Gulf of Mexico. Species composition was dominated by members of the genus Bothus, which had a high frequency of occurrence in the epipelagic zone throughout the year. Citharichthys spilopterus and Trichopsetta ventralis were the second- and third-most abundant and frequently occurring taxa, respectively. Detailed spatial analyses of taxa in the epipelagic zone revealed that larvae of Citharichthys spilopterus were only collected in winter and occurred most frequently near the continental shelf break, while early life stages of Bothus spp. were more abundant at the northern convergence flow of a large anticyclonic Loop Current eddy during spring and summer.
44

Essays in Health Economics

Petrova, Olga 03 July 2017 (has links)
Over the past two decades, a growing body of literature within health economics has provided evidence of the impact of fetal conditions on individual’s health and economic outcomes over the entire life course. This dissertation contributes to the field of health economics by investigating the effects of two distinct types of public policies, antimalarial interventions in sub-Saharan Africa and medical marijuana laws in the United States, on early-life health. Chapter 1 adds to the increased understanding of the impact of in utero exposure to large-scale interventions to combat endemic diseases by examining the effects of antimalarial interventions aimed at preventing and controlling malaria in pregnancy on birth outcomes. Since the year 2000, a coordinated international effort against malaria has led to a significant scale-up of intervention coverage across sub-Saharan Africa. One of the objectives of this undertaking was to improve maternal and early-life health. This chapter investigates the effect of access to malaria prevention and control measures, including insecticide-treated nets, intermittent preventive treatment in pregnancy, indoor residual spraying, and artemisinin-based combination therapy, on birth weight. I exploit the geographic and time variation in the rollout of antimalarial interventions in sub-Saharan Africa across regions with different levels of initial malaria prevalence to analyze 277,245 live births in 22 countries from 2000 to 2013 in a continuous difference-in-differences estimation framework and find that the diffusion of intermittent preventive treatment among pregnant women contributed to the reduction of low birth weight incidence in sub-Saharan Africa. I do not find other antimalarial interventions to be associated with significant improvements in birth outcomes. Chapter 2 provides an investigation focused on examining the impact of medical marijuana laws in the United States on birth outcomes. As of June 2017, medical marijuana laws which liberalize the cultivation, possession, and use of cannabis for allowable medical purposes have been adopted by 29 states and the District of Columbia. The expansion of state-level legislation allowing for medical marijuana use has fueled an ongoing debate regarding drug policy. Despite a growing interest in investigating and quantifying both direct and indirect effects of marijuana liberalization policies, little is known about how they affect early-life health. Using data on the entire universe of births in the U.S. between 1990 and 2013 and a difference-in-differences research design, I find no evidence to support the hypothesis that medical marijuana laws have a negative impact on birth weight and gestation, however I also find that medical marijuana laws are associated with reductions in Apgar scores.
45

Development and dynamics of gut microbial communities of migratory shorebirds in the Western Hemisphere

Grond, Kirsten January 1900 (has links)
Doctor of Philosophy / Division of Biology / Brett K. Sandercock / Gastrointestinal microbiota play a vital role in maintaining organismal health, through facilitating nutrient uptake, detoxification and interactions with the immune system. Shorebirds vary widely in life-history characteristics, such as habitat, migration and breeding system, but the dynamics of their gut microbial communities are unknown. In my dissertation, I investigated composition and dynamics of gut microbiota in migratory shorebirds from embryos to 10 day old chicks, and determined environment and host-related factors affecting gut microbial communities of adults. First, I tested whether precocial chicks from three species of arctic-breeding shorebirds acquire gut microbiota before or after hatching using next-generation sequencing. In addition, I documented the dynamics of gut microbial establishment. I showed that gut microbiota were absent in shorebird embryos before hatching, but that stable gut communities established within the first three days after hatching. In addition, gut microbiota of young shorebird chicks were more similar to the environmental microbiome than later in life, suggesting that the environment is a likely source for microbial recruitment. After reaching adulthood, shorebirds migrate long distances, potentially exposing them to a wide range of microorganisms. Host phylogeny and environmental factors have both been identified as drivers of gut microbiota composition in birds in previous studies. The second part of my project aimed to compare the relative importance of host and environmental factors that underlie variation in gut microbiota composition in eight species of migratory shorebirds sampled across the North American Arctic. I found that sampling site was the main driver of variation in gut microbiota of Arctic-breeding shorebirds, and that site-related variation in gut microbiota of shorebirds was a result of differences in core bacterial taxa that occurred in more than half of the analyzed samples. A relatively large influence of local environment on gut microbiota composition of chicks and adults lead to the question: how does site affect pathogen prevalence in shorebirds? Migratory behavior has been hypothesized to have evolved as a response to variation in climatic conditions and food availability, to avoid predation, and to reduce risk of exposure to pathogens. The migratory escape hypothesis predicts avoidance of high disease prevalence areas through migration, and has been proposed as one of the main reasons that many bird species migrate to the Arctic for breeding. To test the migratory escape hypothesis in shorebirds, I screened for prevalence of seven known avian pathogens in shorebirds at different stages of migration. I did not detect the majority of pathogens we tested for, with the exception of Campylobacter jejuni and C. coli. Prevalence of C. jejuni in shorebirds was linked to sampling sites but not shorebird species. My dissertation is the first comprehensive study to broadly characterize the gut microbiota in shorebirds. Overall, local environment emerged as an important factor in shaping microbiota composition in Arctic-breeding shorebirds throughout my dissertation research. The role of local environment in shaping gut microbiota invites future investigations of the interactions among shorebirds and the microorganisms present in their environment, as well as the functions gut microbiota perform within their shorebird hosts.
46

The influence of early life adversity and recent life stress on psychological trajectories in women with ovarian cancer

Clevenger, Lauren Angela 01 August 2016 (has links)
Ovarian cancer is a malignancy characterized by poor prognosis, high levels of distress, and impaired quality of life (QOL). Investigation into the contributors to QOL is of psychological and prognostic significance in cancer. Contemporary stress theories and empirical accounts identify early life adversity and recent life stress as those sources which exert significant impact on physical and psychological health. To date, life stress research in cancer has yielded few designs which operationalize both indices of early life and recent life stress exposures. Moreover, despite the high-resolution stress data provided by the Life Events and Difficulties Schedule (LEDS) system, no studies to date comprehensively operationalize the early life adversity data obtained during each interview. Therefore, the proposed study is the first of its kind to comprehensively obtain ratings and examine effects of early life adversity data collected as part of the LEDS interview. It is also the first to examine independent influences of differentially timed life stress indices on psychological variables important to psychosocial functioning in ovarian cancer. Early life adversity was experienced by 43.1% of the sample. Adversity varied in content, number of occurrences, and severity. Ongoing difficulties, but not recent life events or early life adversity, were significantly associated with pre-surgical depression and QOL. Ongoing difficulties were also associated with lower depression, sleep, and QOL scores at all time-points. Early life adversity was associated with a poorer trajectory of sleep and QOL over the first year post-diagnosis. Findings are discussed with attention to behavioral and biological mechanisms. Applications to generative and cumulative theories of life stress are proposed. These findings lend support to the potential benefit of interventions aimed toward practical support and stress management in patients with ovarian cancer, as well as provide guidelines for use of early life adversity data obtained through the LEDS interview.
47

Asociación entre eventos adversos durante la niñez y desórdenes mentales autorreportados: Análisis del Censo Nacional Penitenciario Perú 2016 / Association between Early Life Stressors and self-reported mental disorders: Analysis of the 2016 Peruvian National Penitentiary Census

Castañeda Montenegro, Giancarlo, Ascarruz Asencios, Josue Jonatan 23 July 2019 (has links)
Introducción: Estudio pionero en analizar los datos referentes a ansiedad y depresión del Censo Nacional Penitenciario 2016 (CNPP). Los eventos adversos en la niñez (ELS) se encuentran relacionados a nivel epigenético a depresión y ansiedad. Los problemas de salud mental son la primera carga en años de vida perdidos por discapacidad al año 2016 en el Perú. La depresión y ansiedad tienen alta prevalencia en sistemas penitenciarios internacionalmente. Objetivos: Determinar si la exposición a ELS está asociada a depresión y ansiedad autorreportadas en la población penitenciaria peruana. Materiales y métodos: Análisis secundario a partir de la base de datos del CNPP. Las variables dependientes fueron el autorreporte de depresión y/o ansiedad. Las variables independientes fueron la exposición a los siguientes ELS por parte de los cuidadores: Abuso físico, consumo de alcohol, consumo de drogas y situación de abandono. La asociación fue de tipo multivariada, estimada mediante el cálculo de razones de prevalencia ajustadas (RPa) con intervalos de confianza al 95% mediante la regresión de Poisson con varianzas robustas. Resultados: Se encontró asociación entre ELS y depresión (RPa 1.41, IC 1.34-1.49, p<0,05). Asimismo, se encontró asociación entre ELS y ansiedad (RPa 1.35, IC 1.28 – 1.42, p<0,05). Conclusiones: Se encontró asociación entre los ELS estudiados y depresión, así como con ansiedad autorreportadas. Los resultados de este estudio podrían contribuir al mejor conocimiento de la salud mental de la población penitenciaria peruana con el fin de optimizar sistemas de tamizaje y tratamiento. / Introduction: Neuropsychiatric disease represents the first major cause of disability adjusted life years in Peru. This dissertation analyzes the data referring to anxiety and depression from the 2016 Peruvian National Penitentiary Census. On 2016, mental health problems were the first cause of years lost to disability in Peru. Internationally, both anxiety and depression have high prevalence among inmates. Objectives: Establish association between depression and anxiety in relation to Early Life Stressors (ELS) in the Peruvian imprisoned population, additional factors associated with depression and anxiety were analyzed. Materials and methods: Secondary analysis of the data from the 2016 Peruvian National Penitentiary Census. The assessed outcomes are anxiety and depression; while the exposure variables are ELS, experienced between the ages of 5-12, such as physical abuse, tutor’s alcohol or illegal drugs consumption, neglect. Multivariable analysis has been executed, through the calculus of adjusted prevalence ratios using Poisson's regression model with a confidence interval (CI) of 95%. Results: Association between ELS and self-reported depression (PR 1.41, CI 1.34-1.49, p<0,05). Similarly, association between ELS and self-reported anxiety was found (PR 1.35, CI 1.28 – 1.42, p<0,05). Conclusions: This paper finds significant association between both mental health issues. The acknowledgement of these factors is important inasmuch as the understanding of them, which may help the optimization of screening methods and later treatment of the imprisoned population. / Tesis
48

The relationship between career anchors and employability

Ndzube, Fezeka 06 1900 (has links)
In the post-industrial society, career management has become vitally important for assisting workers to be employable. This study aimed to investigate the relationship between career anchors and employability. The effort of researching these concepts is geared towards adding to the knowledge base in the field of Industrial and Organisational Psychology, so that the current organisation from which the sample was chosen and other organisations in South Africa can adopt a strong career management culture. A quantitative survey using primary data was conducted on a convenience sample (N=108) of full-time employees in a South African financial company. The Career Anchors Inventory (COI) and the Employability Attribute Scale (EAS) were used to gather data. The study found a statistically significant positive relationship between career anchors and employability. In addition, there were significant correlations between the sub-constructs of career anchors and employability, while significant differences in career anchor preferences and employability perceptions between males and females emerged. The only differences in career anchor preferences were detected between racial and age groups. The results indicate a mutual and positive relationship between career anchors and employability, which can be useful in career guidance in the 21st century. / Industrial and Organisational Psychology / M.A. (Industrial and Organisational Psychology)
49

Early Life History of the Mountain Whitefish Prosopium williamsoni (Girard) in the Logan River, Utah

Brown, Lawrence Guy 01 May 1972 (has links)
Growth and food habits of 399 Age 0 mountain whitefish from the Logan River, Utah, were studied between March, 1970, and April, 1971. At the end of their first six months of life, whitefish were 86-96 mm total length and weighed 6-8 grams (wet). Total temperature experience was 2,950-3,430 degree- days above 32° F. The length-weight relationship for Age 0 mountain whitefish was best described by three stanzas with slopes of 4.3333 for fish 12.5-17.0 mm total length, 3.4437 for fish 17.0-55.0 mm total length, and 2.8043 for fish 50.0-112.0 mm total length. Scalation commenced at 30-35 mm total length and was complete at 40-50 mm total length. Feeding began before yolk-sac absorption was complete and 85 percent of the total diet in numbers was chironomid larvae. Age 0 mountain whitefish in the Logan River fed during daylight and evening hours, and selected chironomid larvae and other food organisms 2-4 mm long.
50

Identification and spatiotemporal dynamics of tuna (Family: Scombridae; Tribe: Thunnini) early life stages in the oceanic Gulf of Mexico

Pruzinsky, Nina 02 May 2018 (has links)
Fishes within the family Scombridae (i.e. tunas, mackerels and bonitos) are of high ecological and economic value, as they are heavily targeted by commercial and recreational fisheries. In coastal and open-ocean environments, adults are high-level predators, while larvae and juveniles serve as prey for numerous species. Much is known about the distribution and abundance of adult tunas, but high taxonomic uncertainty and limited knowledge regarding the distributional patterns of larval and juvenile tunas have led to an “operational taxonomic unit” gap in our understanding of tuna ecology. Scombrids were collected across the Gulf of Mexico (GoM, hereafter) during seven research cruises from 2010-2011, as part of the NOAA-supported Offshore Nekton Sampling and Analysis Program, and during five research cruises from 2015-2017, as a part of the GOMRI-supported Deep Pelagic Nekton Dynamics of the Gulf of Mexico Consortium. In this thesis, species composition, distribution, and abundance of tunas collected from the surface to 1500 m depth are characterized in relation to depth, time of year, and physical oceanographic features. A synthesis of the morphological characteristics used to identify the taxonomically challenging larval and juvenile stages of tunas is presented, along with length-weight regressions to fill the data gap on the growth patterns of these early life stages. A total of 945 scombrid specimens were collected, representing 11 of the 16 species that occur in the GoM. The dominant species included: Euthynnus alletteratus (Little Tunny), Thunnus atlanticus (Blackfin Tuna), Auxis thazard (Frigate Mackerel), and Katsuwonus pelamis (Skipjack Tuna). Evidence of sampling gear selectivity was observed, with a MOCNESS (rectangular, research-sized trawl) collecting larvae predominantly, and a large, high-speed rope trawl catching only juveniles. Scombrids were collected primarily in the upper 200 m of the water column. Species-specific environmental preferences and seasonality were identified as the main drivers of tuna spatial distributions across the epipelagic GoM. Integrating aspects of scombrid ecology in neritic and oceanic environments improves management and conservation efforts for this highly important taxon.

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