Introdução: As trissomias 18 (T18) e Trissomia 13 (T13) são respectivamente a segunda e terceira causa mais comum de aneuploidias, com um aumento no diagnóstico dado o desenvolvimento de métodos e protocolos que incluem rastreio ecográfico e bioquímico, com a possibilidade de realizar um diagnóstico pré-natal a partir da realização de cariótipo fetal. São síndromes polimalformativas graves, potencialmente letais, associadas a uma alta taxa de aborto espontâneo, morte intrauterina e uma vida pós-natal curta, com morte neonatal precoce. O presente estudo visa descrever e analisar a história natural destas trissomias em um país onde não há previsão legal para interrupção terapêutica para estes casos. Objetivos Analisar e descrever a história natural das gestações com diagnóstico pré-natal de trissomia 13 e trissomia 18, identificadas através da realização de amniocentese para obtenção de cariótipo, que foram realizadas entre outubro de 1994 até outubro de 2017 no Serviço de Ginecologia e Obstetrícia do Hospital de Clínicas de Porto Alegre e acompanhadas pelo grupo de Medicina Fetal, e assim comparar os dados encontrados nesta casuística local com a literatura atual a respeito do tema. Métodos: Realizado análise dos prontuários das pacientes que realizaram cariótipo fetal através de amniocentese, e fizeram diagnóstico pré-natal de trissomia 13 ou trissomia 18.Quando incompletos, foram realizadas ligações telefônicas para completá-los. A partir dos dados coletados (demográficos, ecográficos, curso da gestação) foram avaliados os possíveis desfechos fetais (abortamento espontâneo, óbito fetal e nascido vivo), descrevendo a sua história natural, e considerando principalmente a sobrevida dos nativivos. Análise estatística usando SPSS versão 18.0. Resultados: Quarenta e duas pacientes foram incluídas, sendo 13 (31%) T13 e 29 (69%) T18. Todos os casos fizeram cariótipo para diagnóstico pré-natal através de amniocentese. 92,9% das pacientes foram encaminhadas devido a malformações detectadas em ecografia. Na avaliação das malformações, encontrou-se que a identificação de fenda labial e/ou palatina (p 0,008), dilatação pielocalicial (p 0,037) e holoprosencefalia (p <0,0001) foram achados ecográficos com significância estatística freqüentes em T13. A taxa de abortamento foi de 9% para T18, enquanto não houve casos em T13. Óbito fetal aconteceu em 46% e 52% dos casos para T13 e T18 respectivamente. A taxa de nascidos vivos foi de 54% para T13, sendo que a mediana de sobrevida foi de um dia (IC95% -33,55-90,40). 71% dos casos morreram nas primeiras 24 horas e dois casos que ultrapassaram a primeira semana de vida: com 14 dias e 180 dias respectivamente. Para T18 a mediana de sobrevida foi de dois dias [IC95% -1,89-13,17]. Cinco casos (45%) faleceram dentro das primeiras 24 horas. Outros 45% morreram na primeira semana de vida. Um caso (10%) ultrapassou o primeiro mês de vida, com sobrevida de 39 dias. Nenhum caso em ambas as trissomias ultrapassou o primeiro ano de vida. Conclusões: Os resultados deste estudo são consistentes com os referenciados na literatura acerca do diagnóstico de T13 e T18, quando realizado no pré-natal. A presença de malformações em ecografia foi o que mais motivou o encaminhamento para o atendimento especializado e realização de procedimentos diagnósticos, sendo identificados alguns achados característicos que podem aumentar a suspeita diagnóstica, quando detectados no exame ultrassonográfico, principalmente para trissomia 13, como são a defeitos de línea media e dilatação pielocalicial. Além disso, foi possível confirmar as características de síndrome polimalformativa potencialmente letal, destas trissomias quando avaliada a história natural, caracterizando-se por uma taxa alta de morte fetal intra-uterina e com uma sobrevida global curta ao nascimento. Este estudo também proporcionará informações importantes para definir condutas e protocolos de manejo e acompanhamento a serem executadas por equipes multidisciplinares treinadas, que permitam adequados processos de aconselhamento pré-concepcional e genético, e assim facilitar a tomada de decisões pela paciente gestante, seu parceiro e a família. Além disso, proporcionará informações que permitam reavaliar as políticas em saúde coletiva, abrindo a discussão sobre se deve também ser considerada a interrupção terapêutica da gestação em casos de trissomia 13 e trissomia 18 a partir do desejo dos pais e da autorização judicial. / Introduction: Trisomy 18 (T18) and Trisomy 13 (T13) are respectively the second and third most common cause of aneuploidies, with an increase in diagnosis given the development of methods and protocols that include ultrasound and biochemical screening, with the possibility of performing a prenatal diagnosis from the fetal karyotype. These are a serious, potentially lethal polymalformative syndromes associated with a high rate of spontaneous abortion, intrauterine death and short postnatal life with early neonatal death. The present study aims to describe and analyze the natural history of these trisomies in a country where there is no consider a legal provision for therapeutic interruption in these cases. Objectives To analyze and describe the natural history of pregnancies with prenatal diagnosis of trisomy 13 and trisomy 18, identified through amniocentesis to obtain a fetal karyotype, which were performed between October 1994 and October 2017 at the Gynecology and Obstetrics Service of Hospital de Clínicas de Porto Alegre and accompanied by the Fetal Medicine Group, and thus compare the data found in this local casuistry with the current literature on the subject. Methods: Analyzed the medical records of patients who performed a fetal karyotype, through amniocentesis, for prenatal diagnosis of trisomy 13 or trisomy 18. When incomplete, telephone calls were made to complete them. The possible fetal outcomes (spontaneous abortion, fetal death and live birth), describing their natural history, and considering mainly the survival of the 16 children were born alive. Data about each patient was collected and organized (demographic, ultrasound, gestation course) in order to do a secondary analysis. Statistical analysis using SPSS version 18.0. Results: Forty-two patients were included, being 13 (31%) T13 and 29 (69%) T18. All cases had a fetal karyotype for prenatal diagnosis through amniocentesis. 92.9% of the patients were referred due to malformations detected on ultrasound. In the malformations assessment, it was found that the identification of cleft lip and / or palate (p 0.008), pyelocalycial dilatation (p 0.037) and holoprosencephaly (p <0.0001) were frequent echographic findings in T13. The abortion rate was 9% for T18, while there were no cases in T13. Fetal death occurred in 46% and 52% of cases for T13 and T18 respectively. The rate of live births was 54% for T13, and the median survival was one day [95% CI - 33.55-90.40]. 71% of the cases died in the first 24 hours and two cases that exceeded the first week of life: 14 days and 180 days respectively. For T18 the median survival was 2 days [95% CI -1.89-13.17]. Five cases (45%) died within the first 24 hours. Another 45% died in the first week. One case (10%) exceeded the month of life, with a survival of 39 days. No case in both trisomies has exceeded the year of life. Conclusions The results of this study are consistent with those referenced in the literature on the diagnosis of T13 and T18, when performed in the prenatal period. The presence of malformations in ultrasound was the most motivated the referral to specialized care and diagnostic procedures, being identified some characteristic findings that can increase the diagnostic suspicion, when detected in the ultrasound examination, mainly for trisomy 13, as they are defects of midline and pyelocalycial dilatation. In addition, it was possible to confirm the characteristics of a potentially lethal polymalformative syndrome of these trisomies when evaluated its natural history, characterized by a high rate of intrauterine fetal death and short overall survival at birth. This study will also provide important information to define management and follow-up procedures and protocols to be carried out by trained multidisciplinary teams that allow adequate preconceptional and genetic counseling processes, and thus facilitate decision making by the pregnant patient, her partner and the family. In addition, it will provide information to reassess collective health policies, opening the discussion on whether to also consider the therapeutic interruption of gestation in cases of trisomy 13 and trisomy 18, based on parental desire and judicial authorization.

This thesis examines the revivalist writings of Jonathan Edwards (1703-1758) and George Whitefield (1714-1770) for evidence that the Great Awakening altered their perspective on revival. It is principally based on primary sources written between 1736 and 1743. Six separate chapters explore their background, their understanding of revival, their efforts at propagating it, their techniques in managing the revival, their defense of revival, and their institutionalization of revival. Both their understandings of revival came from their own observations of the revivals that accompanied their evangelistic efforts. Their theological background, heavily influenced by Calvin, insisted that God was responsible for both conversions and revival. The thesis notes that Whitefield�s and Edwards� use of four primary techniques to propagate revival evolved as they experienced revival. Their preaching, their organization of small, religious education groups, their publishing of sermons, and their written narratives of revival all show signs of adaptation to changing circumstances. Both managed revival by using small groups and publications to guide people way from inappropriate spiritual expressions. These groups and documents also provided opportunities to educate new converts about their spiritual experiences. Edwards and Whitefield had the opportunity to clarify their understanding of revival as they defended the revival against those critics who questioned their claims about God�s role in the religious events of 1735-1743. Both institutionalized revival by interacting with the next generation of evangelical ministers and by making available their doctrines and their own experiences in their published narratives. This propensity to publish their reflections on revival allowed future generations access to their revival principles. The overriding hypothesis of this study is that Whitefield�s and Edwards� understanding of revival grew out of their involvement in revival in the eighteenth century religious revivals of colonial North America and that their revival writings and preaching were attempts to codify and transfer the lessons they had learned about revival to future generations of Christians who might, they hoped, themselves experience a God-ordained time of revival. The key conclusions of this study are that 1) Whitefield�s and Edwards� positions on revival issues developed through repeated exposures to revival, 2) Whitefield and Edwards used similar means to propagate, manage, defend, and institutionalize revival, 3) Whitefield�s sermons and journals themselves express a clear and concise theology, 4) a comparison of Whitefield�s and Edwards� theology refutes the suggestion that the lack of a uniform theology throughout the colonies negates the reality of the Great Awakening, 5) a careful study of Whitefield�s and Edwards� revival writings produces a heightened awareness of the nature of their narrative works, 6) Edwards� revival writings show a concern for worship that is too often missed in studies of his work, 7) Edwards and Whitefield were actively involved in developing, recording, and teaching the principles of authentic revival.

Cette étude doctorale porte sur une matrice polyamide 6.6, utilisé dans les matériaux renforcé fibre de verre courtes, et consiste en la mise en place d'une modélisation thermomécanique, autour de la transition mécanique α du polymère. Une première partie consiste en la mise en évidence expérimentale du comportement thermomécanique du matériau de l'étude. Une campagne d'essais mécanique en traction et cisaillement a été menée, où un effort important sur le protocole expérimental a été mené. Les techniques d'analyse de déformation par corrélation d'images, et de suivi pyrométrique de la température ont, par exemple, été utilisées. La construction de la base expérimentale met à profit les équivalences vitesses / températures, sur une gamme de température comprise entre -10° et +60°, et une gamme de vitesse de déformation comprise entre 10-4 et 10 s-1, soit 21 décades suivant la grandeur caractéristique de ces essais, i.e. la vitesse de déformation équivalente à une température de référence. Une seconde partie consiste en un développement d'un modèle de comportement visco-hyperélastique, décrit dans le cadre formel de la thermodynamique des processus irréversible, et physiquement basé sur les modèles de statistique de chaînes modifiés. L'introduction d'un processus de relaxation, d'une partie de l'énergie élastique emmagasinée dans le réseau comme source d'anélasticité entropique a été proposée, puis confrontée avec la base expérimentale. Le modèle prend en compte les couplages thermomécaniques forts, et permet, avec un nombre de paramètres réduits, de représenter le comportement global de l'ensemble de nos essais expérimentaux.

Anthropogenic activities are responsible for increases in atmospheric CO₂ and climate change. These increases are partly counterbalanced by natural processes, such as carbon uptake in land surfaces. These processes are themselves subject to climate change, creating a coupled carbon-climate system. I investigated the carbon sink that woody encroachment represents, using a Central Texas savanna as study site, and studied how climatic factors influence this carbon sink. Woody plant encroachment, a worldwide structural change in grassland and savanna ecosystems, alters many ecosystem properties, but the net effect on the carbon balance is uncertain. Woody encroachment represents one of the key uncertainties in the US carbon balance, and demands a more detailed understanding. To come to a process-based understanding of the encroachment effect on carbon dynamics, I analyzed patterns of carbon exchange using eddy-covariance technology. I expected the imbalance between carbon uptake and release processes associated with the encroaching trees specifically, to be responsible for the carbon sink. I also expected that the sink would vary in time, due to strong links between carbon fluxes and soil water in this semi-arid ecosystem. I further studied the ecophysiology of the dominant species, as well as soil respiration processes under different vegetation types, and scaled these findings in space and time. I found that the ecosystem was a significant carbon sink of 405 g C m⁻² yr⁻¹. The encroaching trees increased photosynthesis by 180% and decreased soil respiration by 14%, compared to the grassland, resulting in a strong carbon sink due to the encroachment process. The encroaching process also altered carbon dynamics in relation to climatic drivers. The evergreen species Ashe juniper effectively lengthened the growing season and widened the temperature range over which the ecosystem acts as a carbon sink. The drought resistance of the encroaching trees reduced the sensitivity of this savanna to drought. I conclude that encroachment in Central Texas savannas increased the carbon sink strength by increasing the carbon inputs into the ecosystem. Woody encroachment also reduced the sensitivity to climatic drivers. These two effects constitute a direct effect, as well as a negative feedback to the coupled carbon-climate system. / text

Woody plant encroachment, that is, a substantial increase in the abundance of woody plants in a grassland or savanna, occurs in many parts of the world. It often has large effects on plant and animal populations and communities and on ecosystem properties and processes. However, little is known about the dynamics of woody plant encroachment and how these are affected by soils, by topography, and by the spatial pattern of the vegetation. Encroachment in turn can affect the spatial pattern of the vegetation. Using data from historical aerial photographs, I measured changes in woody plant cover and constructed, parameterized and compared a set of dynamic models of woody plant encroachment in central Texas savannas. These models predicted final woody cover from initial woody cover and the initial spatial configuration of woody plants. Then I incorporated soil and topography into these models to determine their effects. Finally, I examined the effects of encroachment on the spatial pattern of the vegetation. Incorporating negative density dependence in our models improved their fit, demonstrating that encroachment is density-dependent. A function that predicted the formation of new woody patches from a density-independent seed supply also improved the models' performance. The improvement in the models that resulted from incorporating the total length of woody-herbaceous edges confirmed that encroachment in this system occurs in part by the outward expansion of woody patches. The spatial pattern of the vegetation changed during woody plant encroachment. Spatial pattern (measured as degree of fragmentation) often had a non-linear relationship with cover. Furthermore, the spatial heterogeneity in fragmentation, that is, plot-to-plot variation in the degree of fragmentation, also changed during encroachment. Topography and soil type had, in general, little effect the dynamics of woody plant encroachment. Therefore, a relatively simple model of woody plant encroachment provided good predictions of woody cover at the end of the time periods. Other systems experiencing woody plant encroachment, forest succession, or invasion by non-native plants could be modeled using the same approach. / text

This report examines the cultural and economic growth of the Texas Hill Country resulting from the construction of the Highland Lake chain. It compares the current political and social climate of the region with the historical past, and offers solutions to avert an inevitable collision between a rising population and the constraints of limited water resources. / text

This thesis examines the revivalist writings of Jonathan Edwards (1703-1758) and George Whitefield (1714-1770) for evidence that the Great Awakening altered their perspective on revival. It is principally based on primary sources written between 1736 and 1743. Six separate chapters explore their background, their understanding of revival, their efforts at propagating it, their techniques in managing the revival, their defense of revival, and their institutionalization of revival. Both their understandings of revival came from their own observations of the revivals that accompanied their evangelistic efforts. Their theological background, heavily influenced by Calvin, insisted that God was responsible for both conversions and revival. The thesis notes that Whitefield�s and Edwards� use of four primary techniques to propagate revival evolved as they experienced revival. Their preaching, their organization of small, religious education groups, their publishing of sermons, and their written narratives of revival all show signs of adaptation to changing circumstances. Both managed revival by using small groups and publications to guide people way from inappropriate spiritual expressions. These groups and documents also provided opportunities to educate new converts about their spiritual experiences. Edwards and Whitefield had the opportunity to clarify their understanding of revival as they defended the revival against those critics who questioned their claims about God�s role in the religious events of 1735-1743. Both institutionalized revival by interacting with the next generation of evangelical ministers and by making available their doctrines and their own experiences in their published narratives. This propensity to publish their reflections on revival allowed future generations access to their revival principles. The overriding hypothesis of this study is that Whitefield�s and Edwards� understanding of revival grew out of their involvement in revival in the eighteenth century religious revivals of colonial North America and that their revival writings and preaching were attempts to codify and transfer the lessons they had learned about revival to future generations of Christians who might, they hoped, themselves experience a God-ordained time of revival. The key conclusions of this study are that 1) Whitefield�s and Edwards� positions on revival issues developed through repeated exposures to revival, 2) Whitefield and Edwards used similar means to propagate, manage, defend, and institutionalize revival, 3) Whitefield�s sermons and journals themselves express a clear and concise theology, 4) a comparison of Whitefield�s and Edwards� theology refutes the suggestion that the lack of a uniform theology throughout the colonies negates the reality of the Great Awakening, 5) a careful study of Whitefield�s and Edwards� revival writings produces a heightened awareness of the nature of their narrative works, 6) Edwards� revival writings show a concern for worship that is too often missed in studies of his work, 7) Edwards and Whitefield were actively involved in developing, recording, and teaching the principles of authentic revival.

Thesis (D. Min.)--Reformed Theological Seminary, 2004. / Abstract and vita. Includes bibliographical references (leaves 295-307).

Thesis (M.A.)--Wheaton College, 2007. / Includes bibliographical references (leaves 85-92).

Thesis (M.A.)--Wheaton College, 2007. / Includes bibliographical references (leaves 85-92).