La mise en place de l’asymétrie droite/gauche (D/G) est fondamentale au développement normal des organismes bilatériens. Cependant, les mécanismes essentiels à la cassure de symétrie ainsi que leur conservation au cours de l’évolution sont encore mal compris. Chez le poisson-zèbre l’organisateur de l’asymétrie D/G ou vésicule de Kupffer (KV), consiste en une sphère remplie d’un liquide mis en mouvement de façon circulaire antihoraire pas le battement de cils motiles. Nous avons observé dans la lumière de la KV la présence de vésicules positives pour la protéine ESCRT Chmp1b. De plus, une diminution du nombre de ces vésicules est associée à l’apparition de défauts de latéralité, ce qui suggère un rôle potentiel de ces vésicules dans la mise en place de l’asymétrie D/G. Nous montrons que malgré sa forme circulaire, le flux de la KV peut transporter de façon asymétrique des vésicules. Deuxièmement, nous avons également montré que la fonction de la protéine Myo1D, impliquée dans l’asymétrie D/G chez la drosophile, est conservée chez le poisson-zèbre. La perte de Myo1D a un impact sur les signaux les plus précoces d’initialisation de la latéralité. De plus, Myo1D interagit de façon fonctionnelle avec la protéine Vangl2, un composant de la voie PCP contrôlant le positionnement et l’orientation des cils de la KV. Ces découvertes établissent ainsi que le système Myo1D représente une machinerie conservée au cours de l’évolution pour l’établissement d’une latéralité chez les animaux. / The proper establishment of Left/Right (L/R) asymmetry is fundamental to normal development in bilaterians. However, the initial mechanisms involved in symmetry breaking and their conservation throughout the course of evolution remain poorly understood. In zebrafish, the L/R organizer region or Kupffer’s vesicle (KV) consists as a fluid filled cavity, whose circular counterclockwise motion is driven by the motion of motile cilia. We have observed the presence of vesicles containing the ESCRT component Chmp1b in the lumen of the KV. Hence, the diminution of their number is associated with laterality defect, suggesting a potential role for those vesicles in L/R asymmetry establishment. We also participate to show that in spite of its overall circular geometry, the KV flow can ensure the directional transport of vesicles in the organ lumen. Secondly, we are also showing that the function of the Myo1D protein, implicated in L/R asymmetry establishment in drosophila, is conserved in zebrafish. The loss of Myo1D leads to an impaired early lateralization. Moreover, Myo1D functionally interact with the protein Vangl2, a component of the PCP pathway, which controls the tilt and positioning of KV cilia. These findings are supportive of a mechanism according to which Myo1D system represents a conserved molecular machinery essential for L/R asymmetry establishment in bilaterians.

Orb-weavers (Araneidae) are a diversified spider family comprising more than 3,100 species in more than 170 genera. Together with 13 other families, they con- stitute to superfamily Araneoidea. The presented thesis focuses on karyotype evo- lution of Araneidae, including its comparison with a related family Tetragnathidae. The results obtained from 19 araneid and four tetragnathid species confirm previ- ously postulated hypothesis that the ancestral karyotype of Araneoidea (including Araneidae) consists of 24 acrocentric chromosomes in males, including two acro- centric X chromosomes of system X1X20. However, there is a tendency of 2n decrease in some araneids due to centric fusions. In these cases, centric fusions affected most autosomes (and sometimes gonosomes as well); number of chromosome pairs de- creased from 11 to six. Three independent reduction events were detected in this thesis. Furthermore, pattern of nucleolar organizer regions (NORs) was studied in this thesis using fluorescent in situ hybridization, since data on evolution of this marker are scarce in spiders. Striking variability in NORs number was discovered, ranging from one to 13 loci. Remarkably, multiple centric fusions were always ac- companied by considerable increase of NORs number. In araneids and tetragnathids possessing...

Orb-weavers (Araneidae) are a diversified spider family comprising more than 3,100 species in more than 170 genera. Together with 13 other families, they con- stitute to superfamily Araneoidea. The presented thesis focuses on karyotype evo- lution of Araneidae, including its comparison with a related family Tetragnathidae. The results obtained from 19 araneid and four tetragnathid species confirm previ- ously postulated hypothesis that the ancestral karyotype of Araneoidea (including Araneidae) consists of 24 acrocentric chromosomes in males, including two acro- centric X chromosomes of system X1X20. However, there is a tendency of 2n decrease in some araneids due to centric fusions. In these cases, centric fusions affected most autosomes (and sometimes gonosomes as well); number of chromosome pairs de- creased from 11 to six. Three independent reduction events were detected in this thesis. Furthermore, pattern of nucleolar organizer regions (NORs) was studied in this thesis using fluorescent in situ hybridization, since data on evolution of this marker are scarce in spiders. Striking variability in NORs number was discovered, ranging from one to 13 loci. Remarkably, multiple centric fusions were always ac- companied by considerable increase of NORs number. In araneids and tetragnathids possessing...

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The evolution and development of eyespot and non-eyespot colour pattern elements was studied in Vanessa butterflies using a phylogenetic approach. A Bayesian phylogeny of the genus Vanessa was reconstructed from 7750 DNA base pairs from 10 genes. Twenty-four non-eyespot and forty-four eyespot color pattern elements from the Nymphalid ground plan were defined and studied and their evolutionary history was traced on the Vanessa phylogeny. Ancestral character states were predicted and the direction of evolutionary changes was inferred for all characters. Five serially arranged eyespots were predicted for the ancestral Vanessa on all wing surfaces. Homologous eyespot and non-eyespot characters on the surfaces of the forewing were more similar than those on the surfaces of the hindwing. Homologous eyespot characters on the dorsal surfaces of fore and hindwings show more similarities than the ventral surfaces, in contrast to what was found for non-eyespot characters. Independent Contrast analysis was also used to study correlations between eyespot characters. Independent Contrast analysis revealed significant correlations between eyespots 2 and 5 and eyespots 3 and 4 on all wing surfaces. This consistency among highly variable eyespot characters suggested a structural hypothesis: the existence of a Far-Posterior (F-P) compartment boundary and organizer could be responsible for the observed correlations. This hypothesis was tested in several ways. First, examination of wing patterns across species from all families of butterflies revealed correspondence between wing cells 1 and 4 and between cells 2 and 3. Second, evaluation of spontaneous mitotic clones in butterflies and moths reveals a peak abundance of clonal boundaries along the vein dividing wing cells 2 and 3. Finally, experimentally generated FLP/FRT mitotic wing clones produced in Drosophila, reveal a clonal boundary posterior to the L5 wing vein, which is homologous to the vein dividing wing cells 3 and 4 in butterflies. Collectively, this suggests the existence of an additional compartment boundary associated with an organizer in wing cell 3 responsible for patterning the posterior portion of insect wings. A model is proposed that predicts that the wing developmental compartment boundaries produce unique combinations of gene expression for each wing sector, permitting eyespot individuation. / February 2016

Cytogenetics of spiders of the infraorder Mygalomorphae is largely unknown. My thesis is focused on the karyotype evolution of spiders of families Hexathelidae Dipluridae, which are basal groups of the superfamily Avicularioidea. In this thesis the evolution of diploid chromosome number, chromosome morfology, and also sex chromosomes are studied. The karyotypes of the mygalomorphs are quite interesting for their diversity. Many members of the family Hexathelidae exhibit extreme systems of a chromosomal sex determination which are composed by many gonosomes X. The meiotic division of males is analyzed. Some species exhibit modifications of this division such as achiazmatic meiosis. Selected markers have been detected by fluorescence in situ hybridization. Keywords: evolution, fluorescent in situ hybridization, karyotype, nucleolus organizer region, sex chromosomes, spider

Resumo: Os triatomíneos são insetos hematófagos de grande importância para a parasitologia humana, pois são transmissores do Trypanosoma cruzi, protozoário causador da doença de Chagas. Além de sua importância médico-sanitária, os triatomíneos destacam-se pela sua citogenética, pois possuem cromossomos holocêntricos e um modelo de meiose incomum, com meiose invertida para os cromossomos sexuais. Recentes pesquisas com marcadores moleculares em triatomíneos tentam compreender a ancestralidade do grupo. Uma das formas de se compreender a evolução entre espécies é a partir da análise de seqüências do DNA ribossômico (DNAr). Por pertencer a famílias multigênicas, cópias individuais do DNAr não acumulam mutações independentemente, resultando em pequena variação intra-específica e relevante diferenciação interespecífica. No presente trabalho foi realizado um estudo comparativo entre as espécies Triatoma maculata e Triatoma pseudomaculata, com base no uso das técnicas citogenéticas convencionais de orceína lacto-acética, impregnação por íons prata, bandamento-C, reação de Feulgen; da técnica de citogenética molecular de bandamento- C CMA/DAPI; e também por meio da análise da região ITS-1 do DNAr, com base no sequenciamento, com o objetivo de avaliar o grau de homologia entre as espécies estudadas. Os cariogramas das duas espécies indicaram dez pares de autossomos (um deles de tamanho maior) e um par de cromossomos sexuais (2n = 22). No ciclo meiótico foi possível observar a fragmentação da região nucleolar no final do estágio difuso. Corpúsculos nucleolares foram observados em alguns dos núcleos em metáfases meióticas de T. pseudomaculata, evidenciando a persistência nucleolar. A técnica de bandamento-C revelou que o cromossomo Y é heterocromático em ambas as espécies. O sequencimento da região ITS-1, indicou que as espécies apresenta... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The triatomines are hematophagous insects of great concern in public health because they are vectors of Trypanosoma cruzi, a protozoan that causes Chagas disease. Triatomines are also of great genetic interest, because that they present holocentric chromosomes and an unusual form of meiosis with post-reductional segregation of sex chromosomes. Recent studies based on molecular markers try to understand the evolutionary history of triatomines. To understand the evolution of a given species, ribosomal DNA (rDNA) analyses are frequently used, which can help to infer evolutionary relationships among species. Individual copies of rDNA do not accumulate mutations independently because they belong to multigene families, resulting in slight intraspecific and important interspecific variation. In this study, a comparative analysis was performed between the species Triatoma maculata and Triatoma pseudomaculata, based on the cytogenetic techniques of lacto-acetic orcein, silver ion impregnation, Cbanding, Feulgen reaction; and CMA/DAPI C-banding. We also compared the species by sequencing the ITS-1 rDNA internal transcribed region in order to evaluate the degree of homology among the studied species. The cariograms of the two species revealed ten autosomes and one pair of sexual chromosomes (2n= 22). In the meiotic cycle, nucleolar fragmentation during the final stages of meiotic prophase I was found. Nucleolar corpuscles were found in some meiotic metaphases of T. pseudomaculata, which is evidence of nucleolar persistence. The C-banding technique revealed that the Y chromosome is heterochromatic in both species. The ITS-1 rDNA sequences showed that the species presented a discharge proximity to each other, and had a high degree of homology (98.5%). The knowledge obtained in this study contributes to the understanding of the interrelation and distribution of those species, and offers... (Complete abstract click electronic access below) / Orientador: Maria Tercília Vilela de Azeredo Oliveira / Coorientador: Lilian Castiglioni / Banca: João Aristeu da Rosa / Banca: Carlos Roberto Ceron / Mestre

O presente trabalho trata da análise da estrutura e da espacialidade na obra de Mies van der Rohe. O objetivo é identificar sistemas e estratégias estruturais diversas ao longo do seu trabalho e entender sua relação com a evolução da concepção espacial de suas obras. Adotou-se como referência para esta análise dois períodos da carreira de Mies: o Período Europeu, de 1906 a 1938, e o Período Americano de 1938 a 1968, nos quais foram identificadas respectivamente quatro fases estruturais, conforme os sistemas estruturais e espaciais utilizados. A investigação centrou-se em quatro obras de referência do arquiteto: o Pavilhão de Barcelona (1928-29), o Crown Hall (1950), o Edifício Seagram (1954) e a Neuegalerie (1968). Compreendendo que o elemento poético da obra do arquiteto, aquele a partir do qual se articulam estrutura e espacialidade, é a tectônica, buscou-se analisar as convergências entre concepção espacial e estrutural e a tectônica destas obras. O resultado mostra que Mies van der Rohe, através de sessenta anos de ensaios e pesquisas estruturais e espaciais, consegue nas décadas de 1950-60 chegar à essência da sua obra: a estrutura como meio ordenador espacial do edifício. / This dissertation analyzes the structure and spatial characteristics on Mies van der Rohe´s work. The goal is to identify many structural strategies and systems throughout Rohe's work in order to understand their relationship with his spatial conception evolution. Two periods of Rohe's career were adopted as reference for this analysis: the European period, from 1906 to 1938, and the American period, from 1938 to 1968. In these periods, four structural stages were identified according to the structural and spatial systems used. The investigation focused on four of his key works: Barcelona Pavilion (1928), Crown Hall (1950), Seagram Building (1954) and Neuegalerie (1968).Understanding that the poetic element within the architect´s work - that from which structural and spatial concepts articulate - is its tectonic element, it was developed here the analysis of the convergence between the space and structural conceptions and the tectonics of the cited works. The dissertation finds that Mies van der Rohe - after 60 years of attempts, and structural spatial researches - achieved, during the 50s and 60s , the essence of his work: the structure as the spatial organizer of the building.

本研究旨在探討使用閱讀網絡圖對於臺灣高中生閱讀理解能力的影響，並分析學習者對於使用閱讀網絡圖後的態度觀感。 根據研究目的，所採用的實驗工具為閱讀理解測驗以及態度問卷。實驗對象為台中市某私立高中的92名學生。實驗進行前，實驗組與對照組的學生們接受閱讀理解前測。在為期六週的教學期間，實驗組接受閱讀網絡圖教學訓練，而對照組則接受傳統的教師講述閱讀教學方式。實驗後，兩組學生接受閱讀理解後測；實驗組另在後測結束後填寫問卷。資料分析透過描述性統計、T檢定、與ANOVA檢視閱讀網絡圖教學的效益；問卷旨在瞭解學生對於閱讀網絡圖輔助閱讀理解的態度和看法。 研究主要結果如下： 1.閱讀網絡圖有助於學生閱讀理解。此外，閱讀網絡圖對於學生在回答克漏字網絡圖題型有助益，但其顯著差異並未反映在選擇題的作答表現上。 2.學生對於閱讀網絡圖抱持正面的態度。第一，他們給予網絡圖正面回饋；第二，他們肯定網絡圖對於閱讀理解及文章架構的助益；第三，他們表示有意願在未來應用閱讀網絡圖於英語文章或其他學科的學習上。 綜合研究結果，本研究透過瞭解閱讀網絡圖在閱讀教學上的效益，期能提供教師對於閱讀網絡圖的使用有更一步的瞭解，以充分幫助學生的英語閱讀學習。 / The present study aimed to investigate the effects of graphic organizer instruction on Taiwanese senior high school students’ reading comprehension. Also, it explored students’ attitudes toward the use of graphic organizers. Based on the purpose of this study, instruments included reading comprehension tests and an attitude questionnaire. Two intact classes of 92 private senior high school second-grade female students in Taichung City participated in the study. The classes were first divided into the experimental group and the control group. Before the treatment, the reading comprehension pre-test was administrated. During the six-week instruction, the experimental group received graphic organizer instruction, while the control group received the traditional reading instruction. After that, the effects of graphic organizer instruction were evaluated through measures of reading comprehension post-test. The attitude questionnaire was distributed to the experimental group right after the post-test. The quantitative analysis of the mean scores on comprehension tests was conducted through descriptive statistics, t-Tests, and two-way ANOVA to indicate the effects of graphic organizers. In addition, the data of the questionnaire were analyzed for students’ attitudes toward and perceptions of graphic organizers. The major findings of the study were listed below: 1. The results of comprehension tests showed a significant effect of graphic organizer instruction on reading comprehension of senior high school students. Besides, the graphic organizer instruction positively affected students’ performance on answering cloze graphic organizer questions, while its effect on students’ answering multiple-choice questions was not salient. 2. Information gathered from the questionnaire indicated students’ positive attitudes toward the facilitation of graphic organizers. First, the students expressed positive feedbacks toward the use of graphic organizers. Second, they confirmed the benefits of graphic organizer instruction like increasing their reading comprehension and familiarizing themselves with text structure. Third, they generally showed their willingness to apply the use of graphic organizers to future learning while reading English articles or studying other subjects. To conclude, this study may be of importance in understanding the effectiveness of graphic organizers in its application of reading instruction, as well as in providing English teachers with a better understanding of how to use graphic organizers so as to offer learners with best help.

The correct development of multicellular organisms is tightly regulated by intrinsic and extrinsic factors at specific time points. Disturbance on any level of these multiple processes may result in drastic phenotypes or eventually death of the organism. The midbrain-hindbrain boundary (also termed isthmic organizer) is a region of high interest as well in early as also in later development. The isthmic region carries organizer identity by the expression and subsequent release of FGF8. False patterning events of this region in early developmental stages would therefore display dramatic results over time. As it has been shown that the midbrain-hindbrain boundary (mhb) in the zebrafish is a compartment (or lineage restriction) boundary I tried to understand the underlying molecular mechanism for its correct establishment. In this work I focused both on embryological, molecular and genetic means to characterize involved molecules and mechanisms. In the first part of the thesis I followed in vivo cell transplantation assays, having started with an unbiased one. Cells of either side the mhb were challenged with this boundary by bringing them into direct cell contact with their ectopic counterpart. In a biased approach, cells overexpressing mRNA of specific candidate genes were transplanted and their clonal distribution in host embryos was analyzed. In the second part of the thesis I started interfering with specific candidate genes by transiently knocking down their protein translation. The adhesion molecules of the Eph/ephrin class had been shown to restrict cell mixing and thereby creating compartment boundaries in other tissues, such as the hindbrain, in the zebrafish and other organisms. Additionally, we generated several stable genetic mutant lines in cooperation with the Tilling facility at the Max-Planck-Institute. The only acquired potential null mutant ephrinB2bhu2971 was analyzed and characterized further. I observed that a knock down or knock out of only one of the ephrinB2 ligands does not seem to be sufficient for a loss of compartment boundary formation. The combinatory approach of blocking translation of EphrinB2a in ephrinB2bhu2971 mutants gave very complex and interesting phenotypes, which need to be investigated further.