Os Xenarthra representam um clado de mamíferos eutérios. Pouco se sabe sobre a evolução morfológica craniana do grupo. Esta tese iniciou os estudos relativos a esta questão com base na genética quantitativa, na morfometria e na sistemática, e teve por objetivos específicos: 1) avaliar empiricamente se as matrizes de variância e covariância fenotípica (matriz-P) dos diversos gêneros de Xenarthra estudados podem ser utilizadas como substitutas das respectivas matrizes de variância e covariância genética aditiva (matriz-G), uma vez que não existem matrizes-G estimadas para os Xenarthra, e também se elas podem ser utilizadas em estudos macroevolutivos; 2) testar se a diversificação morfológica craniana no grupo ocorreu somente através de deriva genética; e 3) compreender como a relação entre os caracteres morfológicos (módulos) e a magnitude geral de integração podem influir na evolução morfológica craniana. Além destes objetivos focados na evolução do grupo, também foi escopo desta tese inferir o hábito alimentar de taxa fósseis do final do Pleistoceno/início do Holoceno para melhorar o conhecimento sobre a ecologia de alguns grupos fósseis. O banco de dados utilizado foi composto por medidas lineares de aproximadamente 1150 espécimes adultos, representando 12 dos 14 gêneros atuais e sete dos diversos gêneros extintos de Xenarthra. Com base nesses dados, matrizes-P de variância e covariância e de correlação foram estimadas para cada gênero. Essas matrizes foram posteriormente comparadas par a par para avaliar a semelhança na estrutura das diferentes matrizes. Também a partir dessas matrizes, foram obtidas as variâncias entre e intra populações para testar se a diversificação morfológica ocorreu de acordo com a expectativa teórica de diversificação sob a ação exclusiva de deriva genética. As mesmas matrizes-P foram comparadas a diferentes matrizes teóricas de hipóteses de modularidade craniana. As matrizes teóricas expressaram a relação entre os caracteres com base no desenvolvimento e/ou desempenho de função compartilhado pelas partes do crânio. Para cada matriz-P de correlação calculou-se a magnitude geral de integração. Além disto, a dieta dos grupos extintos foi inferida através de análises de funções discriminantes a partir da relação entre forma e função dos animais atuais. Os resultados obtidos indicam que as matrizes-P dos diversos gêneros são similares entre si, o que sugere que matrizes-P podem ser utilizadas tanto como substitutas das matrizes-G quanto no contexto macroevolutivo. Os resultados obtidos refutaram a hipótese nula da diversificação morfológica craniana ocorrendo somente por deriva genética, ao menos nos níveis mais inclusivos da filogenia dos Xenarthra. Consequentemente, a seleção natural provavelmente atuou neste processo de diversificação. Os resultados também sugeriram que o crânio desse grupo está organizado em módulos, sendo os módulos mais conspícuos os relacionados à face. Além disso, foi detectada grande variação na magnitude geral de integração entre gêneros. A variação no padrão modular, mas principalmente na magnitude geral de integração, faz com que os gêneros apresentem diferenças nas possíveis capacidades de responder de forma alinhada às pressões seletivas. Por último, as análises morfofuncionais indicaram elevada diversidade de hábitos alimentares entre os Xenarthra extintos / Xenarthra are an eutherian mammal clade and little is known about their cranial morphological evolution. This thesis has initiated studies related to this topic and, based on quantitative genetics, morphometrics and systematics, aimed to: 1) empirically assess if the phenotypic variance and covariance matrices (P-matrix) of several genera can be used as surrogates for their respective additive genetic variance and covariance matrices (G-matrix), since G-matrices for Xenarthra are not available, and also if P-matrices can be used in macroevolutionary studies; 2) test whether the skull morphological diversification within the group occurred only through genetic drift; and 3) understand how the relationship between the traits (modules) and overall magnitude of integration may influence cranial morphological evolution. Besides these objectives focused on the evolution of the group, it was also within the scope of this thesis to infer the feeding habits of late Pleistocene/early Holocene fossil taxa to better understand the ecology of some fossil groups. The database used consist of linear measurements of approximately 1150 adult specimens, representing 12 of the 14 extant genera and seven of the several extinct genera of Xenarthra. The data gathered were used to estimate variance/covariance and correlation P-matrices for every genus. These matrices were compared between pairs of genera to evaluate the matrices\' structural similarities. Based on these matrices, within and between population variances were obtained and it was tested whether morphological diversification was in accordance to the theoretical expectation of diversification under genetic drift alone. The same matrices were compared to theoretical matrices expressing modularity hypotheses. These theoretical matrices represent the relationship among traits in reference to the shared development and/or function of different skull\'s anatomical regions (modules). For every correlation P-matrix the overall magnitude of integration was calculated. Moreover, the extinct groups\' diet was inferred through discriminant function analysis relying on the relationship between form and function of extant animals. Results indicate that P-matrices from several genera were structurally similar. This suggests that P-matrices can be used as surrogates of their G-matrices and in the macroevolutionary context. Results refuted the null hypothesis of cranial morphological diversification occurring only due to genetic drift, at least in more inclusive levels of Xenarthran phylogeny. Consequently, natural selection probably acted on this diversification process. The results also suggested that the Xenarthran skull is organized in modules, and the most conspicuous modules are in the face region. A large variation in the overall magnitude of integration among genera was detected. The variation in the modular pattern, but especially in the overall magnitude of integration, allows genera to differ in their potential capacity to respond aligned with selective pressures. Finally, morphofunctional analyses indicate a high diversity of feeding habits among extinct Xenarthra

Os padrões de covariância genética entre caracteres, expressos pela matriz de covariância aditiva G, desempenham um papel importante na evolução de morfologias complexas, visto que esta matriz influencia a direção e magnitude da resposta à seleção em uma população. Assumindo-se a estabilidade da matriz G ao longo do tempo, pode-se testar explicitamente hipóteses acerca da influência de processos evolutivos sobre a diversificação. Espera-se que esta matriz influencie os padrões expressos por sua equivalente fenotípica P, devido a contingências funcionais e ontogenéticas na relação entre genótipo e fenótipo, que levam à estruturação de modularidade nesta relação, de modo a otimizar a evolvabilidade. No presente trabalho, investiguei a estrutura da covariância genética no crânio e mandíbula de uma população do roedor sigmodontíneo Calomys expulsus, com o objetivo de estimar a similaridade entre covariâncias fenotípicas e genéticas; também avaliei a influência de padrões de modularidade sobre ambos os níveis de organização da variação morfológica. As matrizes P e G que obtive para o crânio e para a mandíbula se mostraram bastante similares no que diz respeito à sua estrutura de covariação e se relacionam parcialmente às hipótese de modularidade estabelecidas. Os resultados que obtive aqui são bastante similares àqueles obtidos para os mamíferos como um todo, portanto suportando a hipótese de estabilidade no padrão de covariâncias genéticas e fenotípicas na evolução do grupo. / Patterns of genetic covariance between characters (represented by the additive covariance matrix G) play an important role in the evolution of morphological complexes, since they influence the direction and norm of the response to selection in a population. Therefore, the assumption that G-matrices are stable through evolutionary timescales allows evolutionary biologists to infer the influence of evolutionary processes that operate over biological diversification. These matrices are also expected to influence the patterns expressed in their phenotypic counterparts (P-matrix), because of the imposition of multiple developmental and functional contingencies over the genotype/phenotype map, that leads to its modular organization in order to increase evolvability. Here, I have investigated patterns of genetic covariance structure in the skull and mandible of a population of the vesper mouse Calomys expulsus in order to estimate the level of similarity between additive and phenotypic covariances; I have also evaluated the influence of expected patterns of modularity over both levels of morphological variation. For either skull and mandible, I have obtained P- and G-matrices that are strongly similar in their structure; these matrices also support the modularity hypotheses for developmental and functional constrains, akin to the overall results obtained for mammals, thus supporting the hypothesis of stability in genetic and phenotypic covariance structure in mammalian evolution.

An Yucatan Micropig(R) wurde überprüft, ob die systemische Applikation von Wachstumshormon (GH) in der Lage ist, die Regeneratkonsolidierung bei der Distraktionsosteogenese signifikant zu beschleunigen. Es erfolgte die Entwicklung eines speziellen externen Fixateurs (Halbringf.) mit welchem biomechanische in-vivo Messungen durchgeführte werden konnten. Ebenso wurden serologische, sonographische, röntgenologische, computertomographische, histomorphometrische und post mortem biomechanische Untersuchungen entwickelt und durchgeführt. Die Applikation von rekombinantem spezies-spezifischen Wachstumshormon bei der Distraktionsosteogenese zeigte bei dem von uns gewählten Tiermodell eine signifikante Beschleunigung der Regeneratkonsolidierung. Die biomechanischen Messungen ergaben eine mehr als verdoppelte Steifigkeit und Festigkeit der distrahierten Tibiae nach nur 10 Tagen Konsolidierungszeit im Vergleich zur Kontrollgruppe. Die CT erbrachte für die mit GH behandelten Tiere einen signifikant erhöhten Mineralisierungsgrad im Regenerat, zum gleichen Ergebnis kam die digitale Lumineszenzradiographie und die sonographische Vermessung des Regeneratdurchbaus. Somit zeigten alle Meßmethoden eine deutliche Beschleunigung der Regeneratkonsolidierung durch systemisch appliziertes GH. In den serologischen Untersuchungen fand sich eine signifikante Korrelation zwischen dem Serumspiegel der b-ALP und dem des IGF-I. Dies ist ein Hinweis darauf, dass die Wirkung des Wachstumshormons auf das Regenerat durch seinen Mediator IGF-I bedingt ist. / To investigate the effect of systemic growth hormone (GH) application experiments were performed in a micropig animal model. Systemic daily s.c. injection of species-specific recombinant GH was investigated in Yucatan micropigs to evaluate the effect on intramembranous bone formation in distraction osteogenesis. Quantitative computed tomography (qCT), quantitative ultrasound, digital luminescence radiography, biomechanical in-vivo and post mortem testing, serological investigations as well as histomorphometric analyses were performed to investigate differences in regenerate formation. Systemic GH administration significantly increased in the present animal model the torsional stability of the regenerate in-vivo as well as post mortem in comparison to the contralateral side. Also all additional methods showed an accelerated regenerate consolidation in case of GH application. Systemic Insulin-like growth factor -I levels correlated well with the bone specific alkaline phosphatase levels. This may indicate, that the effect of GH on the distraction osteogenesis is IGF-I mediated.

The purpose of this study was to develop a methodological approach using secondary data that researchers, faculty, and staff can utilize to assess student course performance and to identify the input and course environment factors that best predict student course success in an undergraduate lecture capture quantitative methods course. Using Astin and antonio (2012)’s Input Environment and Outcome (IEO) Model as a framework, this quantitative study examined both input variables that students bring to a course as well as the course environment factors that students experience in the course. Three secondary data sources were utilized and analyzed using descriptive and multivariate statistics. The findings revealed that students with higher levels of student course engagement and academic self-concept were more likely to achieve student course success in this lecture capture quantitative methods course. In addition, prior University GPA along with live-class attendance, discussion board posts, and course quiz and exam scores were the strongest predictors of student course success. The largest implication from this study was the methodological approach developed to identify factors that predicted student course success. This approach can be used to help faculty identify course-embedded measures for assessment as well as develop Keys for Success to help future students succeed in difficult courses. While this study added significantly to the limited research on lecture capture courses, future research should further explore qualitative aspects of the course, such as motivation and student video-viewing behaviors, as well as additional impacts on physical attendance in lecture capture courses. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2018. / FAU Electronic Theses and Dissertations Collection

Reading comprehension emerges as an important skill set in the early elementary grades. It is supported by component skills including decoding, linguistic knowledge including vocabulary and syntactic knowledge, as well as more complex, higher-level components such as inference making and comprehension monitoring. Theoretical understanding of reading comprehension has historically included reader-focused models, as well as models that include reader-text interaction and text-task interaction. Together, the dimensions of reader, text, and task represent the conceptual space in which comprehension can occur. Using a crossed random-effects model, the probability of a correct item response can be modeled as a function of reader, text, and item characteristics. This approach has been used in several studies of reading comprehension, with informative results. However, to date this work has focused on older readers, or has used relatively small samples of readers. In this study, a crossed random-effects modeling approach was used to analyze a large data set consisting of item response data from a sample of 2,723 Grade 3 students. Student-level predictors of vocabulary knowledge, syntactic knowledge, and word recognition, as well as several categorizations of item type, and passage-level predictors of lexile and several indices of passage complexity were found to be significant predictors of reading comprehension. Cross-level interactions were investigated, and significant interactions were found between student and item predictors, and between student and passage predictors. Approximately 50% of variance in reading comprehension across students was explained by the student-level predictors, but only 18-22% of variance across items was explained by the passage-level and item-level predictors. Results from this study suggest that for Grade 3 readers, the strong predictive relations between student predictors of syntactic and vocabulary knowledge to reading comprehension may be moderated by some aspects of item and task demands. However, for this large-scale, multiple choice assessment of reading comprehension, variability in items and passages was largely unexplained. Results are discussed in the context of theoretical accounts of reading comprehension, from which the item and passage predictors are derived. / A Dissertation submitted to the School of Communication Science and Disorders in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Summer Semester 2017. / July 26, 2017. / Florida Assessments for Instruction in Reading, grade three, item response modeling, multilevel modeling, reader-text interactions, reading comprehension / Includes bibliographical references. / Hugh W. Catts, Professor Directing Dissertation; Christopher Schatschneider, University Representative; Carla Wood, Committee Member; Donald Compton, Committee Member.

Corruption is an area that has intrigued plenty of political scientists. This thesis is an attempt to examine how corruption is affected by the sheer amount of public outsourcing with a sample of countries used in a qualitative multivariate analysis. The variables used to control the correlation are inspired by previous research on what causes corruption, while the sample of countries used are those countries that had representation in the indexes used between 2012 to 2015. The main findings are that spending more on public outsourcing tend to lead to slightly less corruption. These results are inconclusive since the main findings was a non-statistically significant when introduced to my set of control variables. However, there is a silver-lining to this inconclusiveness, that being to pinpoint a mechanism for outsourcing and/or corruption: civil wages.

Many people view climate change as one of the top issues facing the world today. As a result, a better understanding of how climate change messages are communicated has become increasingly important. Additionally, with the progression of today’s society into that of highly-visual culture, opportunities for the investigation at the intersection of climate change and visual content would be of great benefit to academia and society, as a whole. More specifically, providing insight into how climate change visuals are framed and what their relationship is to emotions would support visual framing theory and present opportunities to strengthen climate change messaging in the future. Taking a quantitative approach, this research deploys experimental design to test hypotheses and answer research questions on the relationships among three climate change visual frames (causes, impacts, solutions), emotional experience, and climate change salience. In addition, to attempt to provide further insight into these relationships, the personality traits neuroticism and extraversion are tested as moderators. A sample provided from Amazon Mechanical Turk (n = 289) was evenly disturbed between three experimental conditions, each representative of one of the climate change visual frames. Statistical analysis was then utilized to generate results in response to hypotheses one thru eleven and research questions one and two. The findings from this study show that climate change visual frames each generate specific emotional experiences upon viewing. The causes and impacts climate change visual frames result in a negative emotional experience, while the solutions climate change visual frame generates a positive emotional experience. However, this research found no support for the personality traits neuroticism or extraversion playing a role in that response. Similarly, there was no connection found between emotional experience and climate change salience. The findings of this research, however, ultimately support the effectiveness of climate change visual frames without their traditional accompanying text, in the form of a caption or story, and contribute to visual framing theory. Considering the effectiveness of stand-alone climate change visual frames in generating positive and negative emotional experiences can prove useful for practitioners in the creation of future climate change content.

Des changements de méthylation de l’ADN peuvent affecter l’expression des gènes et pour certains être transmis au travers des générations. De telles « épimutations » qui concernent des groupes de cytosines à proximité ou dans les gènes sont donc une source potentielle de variation phénotypique héritable en absence de changements de la séquence de l’ADN. Chez les plantes la méthylation de l’ADN est cependant principalement observée au niveau des séquences répétées. Il reste à déterminer dans quelle mesure les changements de méthylation au niveau de ce type de séquences peuvent être héritées et affecter les phénotypes. Afin de répondre à ces questions, plus de 500 épiRIL (epigenetic Recombinant Inbred Lines) quasi-isogéniques a été générée chez Arabidopsis thaliana. Cette population a été obtenue par le croisement d’un parent sauvage et d’un parent mutant pour le gène DDM1 présentant une très forte réduction du taux de méthylation de l’ADN. Après un rétrocroisement de la F1 avec une plante sauvage, les individus sauvages pour le gène DDM1 ont été sélectionnés et propagées sur 6 générations par autofécondation. Nous avons montré par l’analyse du méthylome de plus de 100 épiRIL que l’hypométhylation induite par ddm1 présente selon les séquences affectées différents degrés de transmission au travers des générations. La réversion de l’hypométhylation concerne des régions associées à une abondance élevée en sRNA de 24 nt. Nous avons utilisé l’hypométhylation stablement transmise dans les épiRIL induite par ddm1 afin de détecter des QTL (Quantitative Trait Loci) affectant le temps de floraison et la longueur de la racine primaire, deux caractères pour lesquels les variations observées dans les épiRIL présentent une héritabilité importante. En dernier lieu, nous avons recherché par différentes approches les variations causales de ces QTL. / Loss or gain of DNA methylation can affect gene expression and is sometimes transmitted across generations. Such epigenetic alterations, which concern clusters of cytosines located near or within genes, are thus a source of heritable phenotypic variation in the absence of DNA sequence change. In plants however, DNA methylation targets repeat elements predominantly and it remains unclear to which extent DNA methylation changes over repeat sequences can be inherited and affect phenotypes. To address these issues, a population of near-isogenic, epigenetic Recombinant Inbred Lines (epiRILs) was generated in Arabidopsis thaliana. These were derived from a cross between a wild type and an isogenic ddm1 mutant line, in which DNA methylation is compromised specifically over repeat elements. After backcrossing of the F1 and selection of the progeny homozygous for wild-type DDM1, the epiRILs were propagated through six rounds of selfing. Analysis of the methylomes of more than 100 epiRILs and of the parents, indicates that ddm1-induced hypomethylation exhibit different patterns of inheritance through generations. Reversion of ddm1-induced hypomethylation is observed for regions associated with high level of 24 nt siRNA. Based on these findings, stable ddm1-induced hypomethylated regions were used to map quantitative trait loci (QTL) for flowering time and primary root length, two complex traits for which substantial heritable variation is observed in the epiRIL population. We finally analysed these QTL by different approaches to find their causal variations.

La progression naturelle des tumeurs consiste en une extension locale, puis à distance (métastase) par migration de cellules dans le sang et la lymphe vers des sites secondaires. Il est donc primordial de pouvoir détecter des cellules tumorales circulantes en plus de l’analyse morphologique et de l’immunocytochimie. De plus, deux technologies (cytométrie en flux et RT-PCR quantitative en temps réel) sont adaptées pour une analyse automatisée, rapide et sensible d’une très faible quantité de cellules. Le but de notre travail a été de mettre au point des systèmes de détection pour l’identification de cellules cancéreuses dans les épanchements péritonéaux et dans le sang. L’étude des biomarqueurs moléculaires apparaît comme une approche complémentaire intéressante pour améliorer l'efficacité du diagnostic dans ce type d'échantillons biologiques. Nous nous sommes intéressés à la mise en évidence de nouveaux marqueurs tumoraux qui pourront être utilisés pour le diagnostic précoce et le pronostic des cancers en utilisant les nouvelles techniques de biologie moléculaire. Il est probable que l'utilisation de multiples marqueurs moléculaires puisse permettre d’évoquer plus particulièrement certains types de cancers. Nous avons pu mettre en place une technique de PCR quantitative en temps réel, nettement plus sensible que la cytologie classique, et nous avons appliqué cette technique à l'étude de marqueurs tumoraux dans les liquides d’épanchement, mais aussi dans le sang pour rechercher et doser l’ARN messager. Nos résultats montrent que la cytométrie en flux adaptée à des lignées cellulaires ne l’est pas pour des prélèvements cliniques. Par la PCR quantitative, il a été possible de quantifier le niveau d’expression des marqueurs tumoraux étudiés en utilisant des plasmides de référence qui ont été préparés pour chaque gène. Plusieurs marqueurs permettent de différencier des épanchements malins et des épanchements bénins, mais surtout les antigènes CLDN4 et Ep-CAM étaient significativement plus élevés (68% et 57%, respectivement) chez les patients avec épanchements malins. L’ARN messager circulant de la CLDN4 était détectable et significativement plus élevée dans les sérums de patients atteints de cancer du sein (64% p<0,05). Les résultats indiquent que l'utilisation d'une combinaison de marqueurs comportant laclaudine 4 est plus susceptible de détecter des cellules malignes et d'être utiles pour le suivi de patients / The natural progression of tumors is a local extension, and remotely (metastasis) by migrating cells in the blood and the lymph to secondary sites. It is therefore essential to detect circulating tumor cells in addition to morphological analysis and immunocytochemistry. In addition, two technologies (flow cytometry and RT-PCR in real time) are suitable for a rapid and sensitive automated analysis of a very small quantity of cells. The aim of our work was to develop detection systems for identification of cancer cells in peritoneal effusions and blood. The study of molecular biomarkers appears as an attractive complementary approach to improve the efficiency of diagnosis in this type of biological samples. We are interested in the identification of new tumor markers that can be used for early diagnosis and prognosis of cancer using new techniques of molecular biology. It is likely that the use of multiple molecular markers can help to raise some specific types ofcancers. We were able to develop a quantitative PCR technique in real time, significantly more sensitive than conventional cytology, and we applied this technique to the study of tumor markers in effusions, but also in blood for detecting messenger RNA. Our results show that flow cytometry well-adapted to cell lines, is not unusable for clinical specimens. For quantitative PCR, it was possible to quantify the expression levels of tumor markers using reference plasmids prepared for each gene. Several markers can differentiate malignant and benign effusions, but especially CLDN4 and Ep-CAM antigens were significantly higher (68% and 57% respectively) in patients with malignant effusions.The circulating CLDN4 mRNA was detectable and significantly higher in the sera of patients with breast cancer (64% p <0.05). The results indicate that using a combination of markers including claudin 4 is more likely to detect malignant cells and be useful for monitoring patients

At embryonic day 3.5 (E3.5), inner cell mass (ICM) cells co-express the transcription factors NANOG and GATA6. Between E3.5 and E4.5, cells of the ICM differentiate into epiblast (Epi) and primitive endoderm (PrE). These two lineages are distinguished by the differential expression of the previously coexpressed transcription factors; Epi cells express NANOG while PrE cells express GATA6. FGF/ERK signalling is responsible for Epi and PrE differentiation but it does not explain the initial co-expression of both factors and how the mutually exclusive expression arises. β-catenin is the downstream effector of Wnt signalling, and it is also found in the membrane forming a complex with E-cadherin. Depending on it subcellular location, β-catenin has been associated with pluripotency and differentiation of mESCs, whose origin is the mouse embryo. My hypothesis was that changes in both cellular pools of β-catenin are involved in ICM differentiation. To characterize Wnt/β-catenin role during preimplantation development, I applied quantitative immunofluorescence analysis (QIF) together with chemical and classical genetics in in vitro and in vivo models. I found that high membrane β-catenin levels are associated with Epi cells from E4.0 stage, while nuclear β-catenin levels are higher in co-expressing cells at E3.5 and PrE precursors at E4.0. My results indicate that increases in nuclear β-catenin levels allow the ICM cells to be specified earlier, determined by an earlier appearance of mutually exclusive expression of GATA6 and NANOG in vitro and ex vivo. Moreover, increased β-catenin levels promote specification towards PrE fate, observed by the presence of higher percentages of PrE cells. Conversely, a decrease in β-catenin levels result in slower ICM specification into Epi and PrE. Finally, modulation of FGF/ERK signalling in mouse embryos, which is the main pathway in this cell fate choice, led to changes in β-catenin subcellular location and levels. Altogether, my results are consistent with a role for Wnt/β-catenin signalling facilitating PrE fate acquisition concomitantly with FGF/ERK signalling.