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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.
71

The Big, Predictable Picture: Construal-Level Reflects Underlying Life History Strategy

January 2011 (has links)
abstract: Integrating research from life history theory with investigations of construal-level theory, the researcher proposes a novel relationship between life history strategy and construal-level. Slow life history strategies arise in safe, predictable environments where individuals give up current reproductive effort in favor of future reproductive effort. Correspondingly, high-level construals allow individuals to transcend the current context and act according to global concerns, such as the type of future planning necessary to enact slow life history strategies. Meanwhile, fast life history strategies arise in harsh, unpredictable environments where the future is uncertain and individuals need to pay close attention to the current context to survive. Correspondingly, low-level construals immerse individuals in the immediate situation, enabling them the flexibility needed to respond to local concerns. Given the correspondence between aspects of life history and construal-level, it seems possible that individuals adopting slow life history strategies should more frequently use high-level construals to assist in transcending the current situation to plan for the future, while individuals adopting fast life history strategies should more frequently use low-level construals to assist in monitoring the details of their harsh, unpredictable environment. To test the relationship between life history and construal, the researcher investigated whether or not a childhood cue of environmental harshness and unpredictability, childhood SES, and a current cue of environmental harshness and unpredictability, local mortality rate, influenced construal-level. In line with past research, the researcher predicted that childhood SES would interact with current cues of local mortality rate to influence construal-level. For individuals growing up in high SES households, a high local mortality rate will lead to an increase in high-level construals. For individuals growing up in low SES households, a high local mortality rate will lead to an increase in low-level construals. Overall, results did not support the hypotheses. Childhood SES did not interact with prime condition to influence either categorization or trend predictions. Examining how the prime interacted with another measure of life history strategy, the Mini-K, yielded mixed results. However, there are several ways in which the current study could be altered to reexamine the relationship between life history strategy and construal. / Dissertation/Thesis / M.S. Psychology 2011
72

TGF-β2 in human milk research: Exploration of a new field methodology and new findings of biosimilar TGF-β2 in non-human milk

Sweetman, Chlöe A. 06 April 2018 (has links)
Objectives: There are three aims for this thesis: the first is to develop a field and laboratory protocol for the storage and analysis of transforming growth factor–beta 2 (TGF-β2) in human breastmilk; second, to validate this protocol and the immunoassay used to assess this new method; and lastly, to explore the ramifications of biosimilar TGF-β2 across multiple milks on human health, growth, and immunity through the review of laboratory findings and previous literature. Rational: Little anthropological research has been done on TGF-β2 in human milk. Anthropology as a discipline is well positioned to provide insight into TGF-β2, combining biocultural, evolutionary, and ecological approaches to holistically illustrate the effects this cytokine has on human immunity. This thesis provides an applied anthropological perspective and methodology on TGF-β2 in human milk. Methods: A protocol was developed for a new method of drying breastmilk on polystyrene microplates. Samples were then reconstituted using reagent diluent with 1% BSA and assayed using a Human TGF-beta 2 DuoSet enzyme-linked immunosorbent assay (ELIZA) assay kit from R&D Systems. Other mammalian milks and infant formula samples were also dried and tested for TGF-β2 concentrations. Validity of the assay and TGF-β2 concentrations were then statistically measured using linear regression analysis and Bland-Altman plots. Results: The results of the first objective in the development of a laboratory and field protocol for drying breastmilk on polystyrene plates for the extraction of TGF-β2 showed this method to hold promise for future application, but lacked statistical power in this study to confirm if this method is viable. The second objective of assay validation was unsuccessful, with the percent coefficient of variation for the intra-assay variation and inter-assay validation 38.28% and 17.70%, respectively indicating that this assay struggled to produce consistent and reliable results from the reconstituted samples. Results from the third objective suggest that biosimilar TGF-β2 in non-human milk can influence human growth and development, the extent of which, however, needs further study. Conclusions: Given these findings, more work with TGF-β2 in milk is required. TGF-β2 is a cytokine which could reveal a great deal about the developmental origins of human immunity and how it is maintained and altered across our life course and therefore an area of biology worth further research.
73

Professoras urbanas no campo, professora rural na cidade : limites e possibilidades na construção de uma leitura de mundo para uma educação do povo

Laureano, Marisa Antunes January 2015 (has links)
Este trabalho visa desenvolver uma análise sobre histórias de vidas que nos permitam perceber os caminhos e descaminhos de professoras para buscar seu lugar enquanto educadoras, tendo, para isso, que compreender a realidade onde atuam. Buscamos perceber como a leitura de mundo, de Paulo Freire, e o conceito de intelectual, de Gramsci, podem ser aplicados nas trajetórias de vidas aqui apresentadas. Como estas mulheres foram se constituindo enquanto professoras e quais os limites e possibilidades que elas encontraram para conduzir suas vidas enquanto educadoras desta ou daquela maneira. Para compreender histórias de vidas e resgatar pontos que nos permitam responder aos questionamentos levantados é preciso embasamentos anteriores que deem uma visão do contexto onde estas vidas estão inseridas. Nesse trabalho delimitamos três momentos históricos para um resgate sobre o processo educacional do país, que atingia uma educação para o povo. Percorremos a década de 1930 e a era Vargas, passamos pelos anos de 1960 e chegamos ao processo de redemocratização com a constituição de 1988. Percebemos, nestes três momentos, avanços e retrocessos, na educação, dando destaque à educação rural/campo, uma vez que o foco de análise e pergunta embasadora desta tese envolvem professoras urbanas que atuam no campo. Como estas professoras, com formação e origem urbana, atuam junto às escolas do campo? E para um contraponto, que nos pareceu instigante, visitamos a história de vida de uma professora rural que atua na cidade. Além de conduzirmos uma narrativa, cujo foco são as vidas das três professoras protagonistas, olhamos, também, para uma escola no campo, que traz suas protagonistas também, e que nos permite perceber caminhos de uma escola em Assentamento rural que não foi ocupada pelos assentados. / This work aims to develop an analysis of stories of lives that allow us to realize the paths and detours for teachers to find their place as educators, what has to understand the reality in which they operate. We seek to understand how the world reading of Paulo Freire and Gramsci's concept of intellectual can be applied in the trajectories of lives presented here. As these women were formed while teachers and the limits and possibilities they found to lead their lives as educators this way or that. To understand life histories and redeem points for addressing the questions raised in the previous one must emplacements that give an overview of the context in which these lives are embedded. In this work we delimited three historic for a bailout on education in the country that reached an education for the people moments. Traverse the 1930s and the Vargas era, passed by the 1960's and got to the democratization process in the constitution of 1988. We see these three moments advances and backward in education, with emphasis on rural education / field, since the focus analysis and embasadora question of this thesis involves urban teachers who work in the field. As these teachers with training and urban origin are close to the school field? And for a counterpoint, what seemed exciting, visited the life story of a rural teacher who works in the city. In addition to conduct a narrative whose focus is the lives of the three protagonists teachers also looked at a school in the countryside, bringing their protagonists too, and that allows us to perceive paths of a school in a rural community that was not occupied by settlers.
74

DETERMINING THE FEASIBILITY OF USING TELEMETRY TO EVALUATE HABITAT USE OF AGE-0 SCAPHIRHYNCHUS STURGEONS IN THE MISSISSIPPI RIVER

Johnson, Jennifer Leigh 01 December 2011 (has links)
Scaphirhynchus sturgeons are species of concern throughout their ranges. To revitalize their populations, a thorough understanding of their habitat use during all life stages is critical. However, limited information exists about fine-scale habitat use during early life. To determine the feasibility of using radio telemetry to monitor habitat use in the field, I assessed growth and survival of age-0 sturgeon tagged with 0.2 g, non-functioning telemetry tags during an eight-week period in a controlled setting and then tested field performance in the Middle Mississippi River (MMR). Three treatments were evaluated: 1) control, 2) internally implanted tags, and 3) externally attached tags. Growth and survival varied across treatment groups (all comparisons P<0.05). Sturgeon with internally implanted tags grew slowly and had low survival, while sturgeon within the control group and those with external tags grew faster and had higher survival (~100%). A trial was conducted to determine swimming performance of each of the treatment groups, which resulted in no differences in critical swimming speed among the tag types. Based on these results, a field-based telemetry evaluation was performed to determine if it is feasible to monitor fine-scale habitat use. Four wild, age-0 Scaphirhynchus sturgeon were externally tagged with functioning radio transmitters in the MMR. After less than 24-h, the tagged fish were no longer detectable, likely due to environmental conditions (e.g., extreme depths and high conductivity). Thus, efforts should be directed to creating a small telemetry transmitter that uses technology (e.g., ultrasonic) that transmits well in deep rivers while maintaining a minimum tag weight and maximizing battery life. Fine scale habitat use of age-0 sturgeon may ultimately be able to be quantified in the MMR and other deep rivers in the future, if technologies improve.
75

Influence of Fishes on Macroinvertebrate Communities in Prairie Stream Permanent Water Refugia

Bonjour, Sophia 01 May 2018 (has links)
Physical factors, such as hydrologic variability, are major structuring forces of prairie stream communities. Macroinvertebrate and algae densities can both decrease sharply in response to floods and drying. Less is known about the influences of biological factors, such as fishes. The influence of fishes on macroinvertebrate communities varies with environmental factors and other biologic interactions, ranging from neutral to strong negative effects on some populations, and the strength of these interactions sometimes appear linked to hydrology. Drying intermittent streams leave permanent water refugia that may be hotspots for interactions between fishes and invertebrates. Effects of fishes on macroinvertebrate communities may vary with invertebrate life cycle stages (e.g., larvae, emerging adults, colonizing adults). I examined macroinvertebrate communities (benthic and emerging) and algal biomass across a range of permanent stream pool sites at Konza Prairie Biological Station with naturally varying densities of fishes. I also manipulated fish densities in a mesocosm experiment to address how fishes may also be effecting colonization during recovery from hydrologic disturbance. Fish biomass had a negative impact on invertebrate abundance, but not biomass or taxa richness, in natural pools. Total fish biomass was not correlated with total insect emergence in natural pools, but orangethroat darter (Etheostoma spectabile) biomass was inversely correlated with emerging Chironomidae biomass (r2 = 0.43, p = 0.047) and individual midge body size (r2 = 0.61, p = 0.014). Predatory fish biomass and a date interaction appeared in top linear models, indicating fish may also delay insect emergence from natural pools. Fish presence reduced abundance of colonizing insects (p < 0.001) and total invertebrate biomass (p = 0.001) in mesocosms. Mesocosm insect communities in pools without fishes were characterized by more Chironomidae, Culicidae, and Corduliidae (p < 0.001 for all). Chlorophyll-a increased between sampling dates in mesocosms, but did not differ between treatments. Not all life stages showed the same response to fishes, illustrating the need for understanding life histories in order to interpret the influence of fishes. Understanding how fishes in prairie streams affect ecosystem structure and function is critical for conservation and management of remaining grassland streams. Results suggest fishes can influence colonization and community structure in prairie stream pools, which serve as important refugia during hydrologic disturbance and source areas for colonists during recovery.
76

Ecology of Veliidae and Mesoveliidae (Heteroptera: Gerromorpha)in Central Europe / Ecology of Veliidae and Mesoveliidae (Heteroptera: Gerromorpha)in Central Europe

DITRICH, Tomáš January 2010 (has links)
Ecology of Veliidae and Mesoveliidae (Hemiptera: Heteroptera: Gerromorpha) was studied in selected European species. The research of these non-gerrid semiaquatic bugs was especially focused on voltinism, overwintering with physiological consequences and wing polymorphism with dispersal pattern. Hypotheses based on data from field surveys were tested by laboratory, mesocosm and field experiments. New data on life history traits and their ecophysiological consequences are discussed in seven original research papers (four published journal papers, two submitted papers and one communication in conference proceedings), creating core of this thesis.
77

Professoras urbanas no campo, professora rural na cidade : limites e possibilidades na construção de uma leitura de mundo para uma educação do povo

Laureano, Marisa Antunes January 2015 (has links)
Este trabalho visa desenvolver uma análise sobre histórias de vidas que nos permitam perceber os caminhos e descaminhos de professoras para buscar seu lugar enquanto educadoras, tendo, para isso, que compreender a realidade onde atuam. Buscamos perceber como a leitura de mundo, de Paulo Freire, e o conceito de intelectual, de Gramsci, podem ser aplicados nas trajetórias de vidas aqui apresentadas. Como estas mulheres foram se constituindo enquanto professoras e quais os limites e possibilidades que elas encontraram para conduzir suas vidas enquanto educadoras desta ou daquela maneira. Para compreender histórias de vidas e resgatar pontos que nos permitam responder aos questionamentos levantados é preciso embasamentos anteriores que deem uma visão do contexto onde estas vidas estão inseridas. Nesse trabalho delimitamos três momentos históricos para um resgate sobre o processo educacional do país, que atingia uma educação para o povo. Percorremos a década de 1930 e a era Vargas, passamos pelos anos de 1960 e chegamos ao processo de redemocratização com a constituição de 1988. Percebemos, nestes três momentos, avanços e retrocessos, na educação, dando destaque à educação rural/campo, uma vez que o foco de análise e pergunta embasadora desta tese envolvem professoras urbanas que atuam no campo. Como estas professoras, com formação e origem urbana, atuam junto às escolas do campo? E para um contraponto, que nos pareceu instigante, visitamos a história de vida de uma professora rural que atua na cidade. Além de conduzirmos uma narrativa, cujo foco são as vidas das três professoras protagonistas, olhamos, também, para uma escola no campo, que traz suas protagonistas também, e que nos permite perceber caminhos de uma escola em Assentamento rural que não foi ocupada pelos assentados. / This work aims to develop an analysis of stories of lives that allow us to realize the paths and detours for teachers to find their place as educators, what has to understand the reality in which they operate. We seek to understand how the world reading of Paulo Freire and Gramsci's concept of intellectual can be applied in the trajectories of lives presented here. As these women were formed while teachers and the limits and possibilities they found to lead their lives as educators this way or that. To understand life histories and redeem points for addressing the questions raised in the previous one must emplacements that give an overview of the context in which these lives are embedded. In this work we delimited three historic for a bailout on education in the country that reached an education for the people moments. Traverse the 1930s and the Vargas era, passed by the 1960's and got to the democratization process in the constitution of 1988. We see these three moments advances and backward in education, with emphasis on rural education / field, since the focus analysis and embasadora question of this thesis involves urban teachers who work in the field. As these teachers with training and urban origin are close to the school field? And for a counterpoint, what seemed exciting, visited the life story of a rural teacher who works in the city. In addition to conduct a narrative whose focus is the lives of the three protagonists teachers also looked at a school in the countryside, bringing their protagonists too, and that allows us to perceive paths of a school in a rural community that was not occupied by settlers.
78

Professoras urbanas no campo, professora rural na cidade : limites e possibilidades na construção de uma leitura de mundo para uma educação do povo

Laureano, Marisa Antunes January 2015 (has links)
Este trabalho visa desenvolver uma análise sobre histórias de vidas que nos permitam perceber os caminhos e descaminhos de professoras para buscar seu lugar enquanto educadoras, tendo, para isso, que compreender a realidade onde atuam. Buscamos perceber como a leitura de mundo, de Paulo Freire, e o conceito de intelectual, de Gramsci, podem ser aplicados nas trajetórias de vidas aqui apresentadas. Como estas mulheres foram se constituindo enquanto professoras e quais os limites e possibilidades que elas encontraram para conduzir suas vidas enquanto educadoras desta ou daquela maneira. Para compreender histórias de vidas e resgatar pontos que nos permitam responder aos questionamentos levantados é preciso embasamentos anteriores que deem uma visão do contexto onde estas vidas estão inseridas. Nesse trabalho delimitamos três momentos históricos para um resgate sobre o processo educacional do país, que atingia uma educação para o povo. Percorremos a década de 1930 e a era Vargas, passamos pelos anos de 1960 e chegamos ao processo de redemocratização com a constituição de 1988. Percebemos, nestes três momentos, avanços e retrocessos, na educação, dando destaque à educação rural/campo, uma vez que o foco de análise e pergunta embasadora desta tese envolvem professoras urbanas que atuam no campo. Como estas professoras, com formação e origem urbana, atuam junto às escolas do campo? E para um contraponto, que nos pareceu instigante, visitamos a história de vida de uma professora rural que atua na cidade. Além de conduzirmos uma narrativa, cujo foco são as vidas das três professoras protagonistas, olhamos, também, para uma escola no campo, que traz suas protagonistas também, e que nos permite perceber caminhos de uma escola em Assentamento rural que não foi ocupada pelos assentados. / This work aims to develop an analysis of stories of lives that allow us to realize the paths and detours for teachers to find their place as educators, what has to understand the reality in which they operate. We seek to understand how the world reading of Paulo Freire and Gramsci's concept of intellectual can be applied in the trajectories of lives presented here. As these women were formed while teachers and the limits and possibilities they found to lead their lives as educators this way or that. To understand life histories and redeem points for addressing the questions raised in the previous one must emplacements that give an overview of the context in which these lives are embedded. In this work we delimited three historic for a bailout on education in the country that reached an education for the people moments. Traverse the 1930s and the Vargas era, passed by the 1960's and got to the democratization process in the constitution of 1988. We see these three moments advances and backward in education, with emphasis on rural education / field, since the focus analysis and embasadora question of this thesis involves urban teachers who work in the field. As these teachers with training and urban origin are close to the school field? And for a counterpoint, what seemed exciting, visited the life story of a rural teacher who works in the city. In addition to conduct a narrative whose focus is the lives of the three protagonists teachers also looked at a school in the countryside, bringing their protagonists too, and that allows us to perceive paths of a school in a rural community that was not occupied by settlers.
79

Aspectos evolutivos da história de vida e estrutura da casca do ovo de lagartos tropiduríneos / Evolutive aspects of life history and eggshell morphology of Tropidurinae lizards

Renata Brandt Nunes 27 August 2010 (has links)
Em lagartos, componentes de história de vida apresentam grande plasticidade fenotípica e evoluem de maneira correlacionada. O número de ovos, por exemplo, tende a ser correlacionado positivamente com o tamanho corpóreo das fêmeas grávidas, tanto em linhagens evolutivas quanto entre indivíduos, embora alguns tipos de hábito pareçam restringir ninhadas maiores. Há indícios de que outros fatores, como componentes climáticos, ou latitude, também sejam determinantes das características de história de vida do grupo, tanto por questões de fisiologia termal quanto ecológicas. Componentes climáticos influenciam ainda diferentes aspectos da reprodução em lagartos, como por exemplo a estrutura e morfologia da casca dos ovos de Squamata, conforme indicam diferenças nestas características entre linhagens de lagartos ovíparos. Neste contexto, o presente trabalho investigou aspectos evolutivos da história de vida de lagartos da subfamília Tropidurinae, e sua relação com componentes climáticos e latitude, através de métodos filogenéticos comparativos. Observou-se que o número de ovos da ninhada é positivamente correlacionado com o tamanho corpóreo ao longo da linhagem dos tropiduríneos. Por outro lado, esse padrão não é observado no caso de hábito escansorial e utilização de frestas de rochas, em razão de possíveis compromissos envolvendo peso e forma corpórea com efeitos na sobrevivência das fêmeas. O tamanho corpóreo em tropiduríneros é maior em regiões geográficas com maiores componentes de precipitação, possivelmente relacionado a disponibilidade de alimento. Há diminuição do tamanho corpóreo com incrementos na distância da linha do Equador, até aproximadamente 1500 km. A partir desse limite, o tamanho corpóreo aumenta. Adicionalmente foi estudada a morfologia e estrutura da casca de Tropidurus torquatus, uma das espécies com distribuição mais ampla dentro da subfamília. A morfologia da casca de Tropidurus torquatus segue o padrão geral para Squamata com algumas particularidades, mas estudos comparativos futuros é que elucidarão padrões evolutivos da morfologia da casca. / In lizards, life history components have great phenotypic plasticity and evolve in a correlated way. Clutch size, for example, tends to be positively correlated to body size of gravid females, when comparing different evolutive lineages or different individuals, though some kinds of habit seems to restrict larger clutches. There are indications that other factors, such as climate components or latitude, also determine characteristics of lizard life history, as a matter of thermal physiology or ecology. Climate factors also affect different aspects of lizards reproduction, for example the structure and morphology of Squamata eggshells, as differences observed in these factors between oviparous lizards lineages indicate. In this context, the present work investigated evolutive aspects of Tropidurinae lizards life history and its relation to climate components and latitude, using comparative phylogenetic methods. It has been observed that clutch size is positively correlated to body size in the Tropidurinae lineage. On the other hand, this pattern is not observed in lizards with scansorial habits or those that inhabit rock crests, maybe due to compromises involving the weight and shape of female bodies that can affect female survival. The body size in Tropidurinae is larger in geographical regions presenting higher precipitation, possibly due to increased food availability. Female body size decreases with increased distance from the Equator until approximately 1500 km. Beyond this limit, female body size increases. Additionally, morphology and structure of eggshells were studied on Tropidurus torquatus, one of the species within the Tropidurinae group with higher latitudinal range of distribution. Tropidurus torquatus eggshell morphology follows the general pattern described for Squamata with some particularities, and future comparative studies are needed to elucidate evolutive patterns of eggshell morphology in the group.
80

I'd Give My Right Kidney to Be Altruistic: The Social Biogeography of Altruism in the United States of America

Garcia, Rafael Antonio, Garcia, Rafael Antonio January 2017 (has links)
The purpose of this dissertation is to model biosocial determinants of group-directed altruistic behavior – exploring the nomological net around it. To do this a study will be presented to determine existing associations among various biological and social predictors and test a life-history-derived causal cascade using a partially exploratory and partially confirmatory statistical technique called Sequential Canonical Analysis to ultimately predict living-donor, non-directed kidney donations (NDKD). Toward that end, some important methodological considerations first need to be discussed. The first consideration revolves around the level of analysis and how this frames the cascade model and its interpretation. Following a general discussion, an exercise in some of the general principles is provided – investigating the higher-order factor structure of the Big-5 personality constructs across two levels of analysis. The second consideration is the use of unit-weighted factor scores and their appropriateness. Following the theoretical discussion, a demonstration is provided – deriving an estimate of genetic relatedness from a set of heterogeneous data sets. Once the methodological considerations have been discussed, the primary cascade model is presented in two parts: 1) the measurement model – operationalizing the measures incorporated into 2) the structural model – testing the proposed causal cascade using Sequential Canonical Analysis. A discussion follows in which the results are summarized, limitations are articulated, and further research directions are explored.

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