Dissertationen zum Thema „Fly eye“

Au cours du développement, l’expression rapide des gènes, la division cellulaire et la différenciation sont essentielles à la formation et au fonctionnement appropriés des tissus et des organismes. Cependant, ce qui donne le tempo des événements de développement ou ce qui régule la vitesse du développement est moins connu. Pour comprendre la base moléculaire de la régulation de la vitesse de développement, nous proposons d’utiliser l’œil de mouche en développement comme nouveau système modèle pour l’étude génétique. Dans le troisième stade larvaire de la drosophile, un front de différenciation balaie du disque imaginal postérieur à antérieur de l’œil, formant des ommatidies rangée par rangée derrière lui. Cette caractéristique rend la progression du front facile à observer. Le mécanisme derrière le mouvement de l’avant est clair, avec le front se déplaçant à environ 1 rangée d’ommatidies toutes les 2 heures. Les puissants outils génétiques utilisés pour étudier la drosophile peuvent nous aider à répondre aux questions qui nous intéressent. À l’aide de disques imaginaux oculaires de drosophile, nous avons d’abord effectué un criblage de l’ARNi pour les gènes nécessaires à la bonne progression du front de différenciation. Nous avons utilisé le système mirr-GAL4/UAS pour introduire des perturbations génétiques dans le compartiment dorsal du disque imaginal de l’œil, le compartiment ventral servant de contrôle interne puisqu’il n’a aucune expression de l’élément UAS. La comparaison des nombres de rangées ommatidiales dans les deux compartiments après perturbation dorsale a permis de découvrir les gènes qui régulent la progression du front de différenciation. Les gènes candidats ont été sélectionnés à partir de gènes métaboliques précédemment criblés dans l’œil adulte, d’autres gènes du métabolisme énergétique / NAD, des gènes du métabolisme ARN / protéine et des gènes connus pour être impliqués dans la progression du front. Notre crible a identifié des gènes d’un petit nombre de voies métaboliques, y compris la chaîne de transport d’électrons et la voie de signalisation de l’insuline. Deuxièmement, pour valider si ces perturbations ralentissent la vitesse de progression du front ou retardent le début de la progression du front, nous avons généré un nouvel outil génétique pour mesurer la vitesse de progression in vivo. À l’aide de cet outil, nous avons mesuré la vitesse de progression du front de différenciation à 18°C et 25°C, et avec différentes perturbations génétiques dorsales. Les résultats ont montré que les gènes perturbateurs de la chaîne de transport d’électrons ou de la voie des récepteurs de l’insuline ralentissent la vitesse de progression du front de différenciation. Enfin, comprendre comment ces perturbations génétiques entraînent une modification de la vitesse de progression du front de différenciation reste une question importante mais largement non résolue. Une hypothèse est que les perturbations génétiques déclenchent des changements vers un état métabolique associé à une vitesse de développement plus lente. Conformément à cette hypothèse, nous avons constaté que l’ARNm Ldh s’accumulait dans les cellules indifférenciées (mais pas dans les cellules différenciées) lors de la perturbation de la chaîne de transport d’électrons, suggérant une glycolyse accrue. La deuxième hypothèse est que différentes perturbations génétiques entraînent des états métaboliques différents. Conformément à cela, la réduction de la signalisation de l’insuline, qui a également entraîné une vitesse de développement lente, n’a pas induit des niveaux plus élevés d’expression de Ldh. Dans les travaux futurs, différents capteurs métaboliques fluorescents qui ont été utilisés chez la drosophile pourraient nous aider à découvrir l’état métabolique à chaque perturbation et nous aider à comprendre si différents états métaboliques pourraient lire différentes vitesses de développement. Il serait utile d’étudier si les gènes que nous avons [...]
During development, timely gene expression, cell division and differentiation are essential for tissue and organism proper functioning and formation. But what sets up the tempo of developmental events, or what regulates the speed of development are less known. To understand the molecular basis of regulation of developmental speed, here, we propose the developing fly eye as a new model system to genetically study developmental speed.In the 3rd larval instar of Drosophila, there is a differentiation front sweeps from posterior to the anterior of the eye imaginal disc, and the ommatidia are formed row by row behind the differentiation front. This character makes the progression of the front easy to be observed. The mechanism of how this front move forward is clear, and the movement speed of the front is about 1 row of ommatidia every 2 hours. Many powerful genetic tools used to study Drosophila could also help us address the question which we are interested in.By using Drosophila eye imaginal discs, first, we performed an RNAi screen for genes required for the differentiation front to travel at proper speed. As mirr only express in the dorsal compartment of the eye imaginal disc, we were using mirr-GAL4/UAS system to introduce the genetic perturbations in the dorsal compartment of the eye imaginal disc, and the ventral compartment which has no expression of UAS element could be considered as the internal control. After dorsal perturbation, comparing the ommatidia row numbers in both compartments will uncover the genes regulate the differentiation front progression speed. The candidate genes are selecting from metabolic genes previously screened in the adult eye, other energy/NAD metabolism genes, some RNA/protein metabolism genes, and genes known to be involved in the progression of the front, etc. Our screen identified genes from a small number of metabolic pathways, including the Electron Transport Chain and the Insulin signaling pathway.Second, to validate whether these perturbations slow down the speed of front progression, or delay the onset of the front progression, we generated a new genetic tool to measure the speed of progression of the differentiation front in vivo. By using this tool, we measured the differentiation front progression speed at 18°C and 25°C, and measured the speed of the front with different dorsal genetic perturbations. The results showed that perturbing the genes of Electron Transport Chain or Insulin receptor pathway slow down the speed of front progression.Finally, understanding how these genetic perturbations result in altered speed of progression of the differentiation remains an important, yet largely unsolved issue. One hypothesis is that genetic perturbations trigger changes toward a metabolic state associated with a slower developmental speed. Consistent with this hypothesis, we found that ldh mRNA accumulated in undifferentiated cells (but not differentiated cells) upon Electron Transport Chain perturbation, suggestive of increased glycolysis. The second hypothesis is that different genetic perturbations result in different metabolic states. Consistent with this, reducing Insulin signaling which also resulted in slow developmental speed, did not induce higher levels of ldh gene expression.In the future work, different fluorescent metabolic sensors which have been used in Drosophila may help us uncover the metabolic state upon each perturbations, and help us understand whether different metabolic state might readout different developmental speed. And whether these candidate genes that we screened were shown to slow down the speed of differentiation front progression also regulate the speed of other developmental events is worth examining in the future

It is generally assumed that the reproductive success of both males and females is not limited by the availability of ejaculates. However, when male ejaculate production is physiologically constrained, the maintenance of high fertility can be an important determinant of fitness. Under the phenotype-linked fertility hypothesis, females can maximise their fertility by choosing mates on the basis of external phenotypic indicators (exaggerated sexual ornaments or displays) of male reproductive quality. I test the phenotype-linked fertility hypothesis in the stalk-eyed fly Cyrtodiopsis dalmanni, a species characterised by sexual dimorphism in the length of the eyestalks that project laterally from the head (eyespan). I demonstrate that females prefer large eyespan males as mates and exhibit higher fertility when housed with large eyespan males than when housed with small eyespan males. I also show that male eyespan predicts the growth rates and final sizes of the accessory glands and testes of males raised under different levels of nutritional stress. Thus male eyespan is a reliable indicator of male reproductive quality, and female preference for this trait can directly increase female fitness through fertility assurance. The higher fertility of large eyespan males is associated with the ability to copulate at a higher frequency rather than greater success on a per-mating basis. Using artificial selection experiments and behavioural observations, I provide evidence that male mating frequency is physiologically constrained by the size of the accessory glands. As eyespan reflects male accessory gland size, females can improve their chances of obtaining an ejaculate by choosing mates with large eyespan. Moreover, I show that males allocate larger ejaculates to females that offer a greater number of fertilisation opportunities. Based on my results, I have proposed a physiological mechanism for the signalling of male mating frequency by male eyespan mediated by circulating levels of juvenile hormone.

Stalk-eyed flies of the family Diopsidae have their eyes laterally displaced on the end of head extensions called “eye-stalks”. Diopsids vary in their degree of sexual dimorphism for eyespan (distance between the eyes). In some dimorphic species it has been well established that females preferentially mate with males possessing exaggerated eyespan. With over 150 members, the family Diopsidae is an ideal model system for analysing the evolution and development of exaggerated sexual traits. Progress towards understanding the mechanisms underlying the development of exaggerated eyespan has been significantly hampered by the lack of modern molecular genetic technology in stalk-eyed flies. I have developed a transgenic protocol in Teleopsis dalmanni, a highly dimorphic diopsid species. I selected and tested embryo microinjection procedures. I used excision assays to compare the activity of three potential transposable element vector systems. Minos and piggyBac demonstrated suitable activity in T. dalmanni embryos but mariner did not. Using Minos and the transgene construct Px3-eGFP, I successfully achieved stable germline transformation in T. dalmanni. A number of transgenic lines were created. In one, a single copy of the insertion was seen to segregate with the X chromosome. I used a histological approach to investigate the relative contributions of cell size and cell number to variation in eyespan. I compared estimates of cell size in the eye-stalks of newly eclosed flies among fully fed and nutritionally stressed individuals. For comparison, I assessed cell size in a non-sexually dimorphic organ, the wing. I found that variation in eyespan was explained, at least in part, by variation in cell size. No inherent difference in eye-stalk cell size was detected between the sexes. The implications of the cell size findings and of the future studies made possible by transgenic technology are discussed.

P2X receptors and pannexins (Panx) are eukaryotic ion channels that are implicated in a range of diseases and conditions including cancer, inflammation and pain sensation and as a result, are important therapeutic targets. Deducing their 3D-structures would enable the use of structure-based drug design to identify novel agonists or antagonists. However, solving eukaryotic membrane protein structures is a significant challenge due to the requirement for high yields of purified folded, functional protein, which are not readily obtainable with conventional over-expression systems. By using P2X receptors and pannexins as model ion channel targets, this thesis aims to test Drosophila melanogaster as a system for the over-expression and functional analysis of eukaryotic ion channels. A number of epitope-tagged P2X and Panx protein constructs were generated and first expressed in HEK-293 cells (rat P2X2-GFP, human P2X4-GFP, rat Panx1-GFP and human P2X4-int-CBD (chitin binding domain)) to allow their expression, glycosylation and oligomeric states to be investigated as markers of protein folding and quality. Subsequently, rat P2X2-GFP and rat Panx1-GFP constructs were successfully expressed in the photoreceptor cells of Drosophila melanogaster, where the photoreceptive membrane in the visual system is organised into a densely packed brush of microvilli, the rhabdomere. This system provides a large surface area of membrane for protein expression. Although the yields of purified protein were lower than expected, rat Panx1-GFP was successfully purified and used for low resolution structural studies with transmission electron microscopy. Rat P2X2-GFP was also expressed in the nervous system of Drosophila under control of a pan-neural, C155-Gal4 driver and was shown to be functional by measuring ATP-evoked action potentials using electrophysiological recordings of the Drosophila taste sensilla. This system was also used to test the activity of an adenosine nucleotide library of 80 compounds. Three nucleotides were identified that elicited responses similar to ATP; these were 2F-ATP, ATPαS and ATPγS.

Meiotic drive genes are a class of segregation distorter that gain a transmission advantage in heterozygous males by causing degeneration of non-carrier sperm. This advantage must be balanced by fertility or viability costs if drive is to remain at stable frequencies in a population. A reduction in male fertility due to sperm destruction reduces the fitness of the rest of the genome, accordingly mechanisms to circumvent the effects of drive may evolve. Such adaptations will have implications for how likely it is that drive will persist. The primary theme of this thesis has been examining fertility consequences of meiotic drive in a Malaysian stalk-eyed fly, Teleopsis dalmanni. I demonstrate that drive carrier males are not sperm limited, despite the destruction of half their sperm. They produce ejaculates with sperm numbers equivalent to wildtype male ejaculates. Furthermore, drive males achieve this with greatly enlarged testes. However, resources are not unlimited; drive males also have reduced body size, and reduced accessory glands and eyespan for their body size. Accessory gland size limits male mating frequency, and male eyespan is a sexually selected trait used in female choice and male-male competition. I discuss how these patters fit with theoretical models that predict males should invest in producing an optimal ejaculate according to levels of expected sperm competition, even if they are low-fertility males. A second interrelated theme of this thesis has been to examine the benefits of polyandry, female mating with multiple males, using wild-caught individuals. Polyandry is widespread across many taxa and almost ubiquitous in insects. However, there is much debate around its proximate and ultimate causes. There are many costs associated with mating and so polyandry requires an adaptive explanation. I utilise data on wild-caught T. dalmanni to explore how natural variation amongst females and males influences fertility gains for females.

Inserita negli ambiti della linguistica applicata e della didattica della lingua spagnola, la presente Tesi esamina la disponibilità e la ricchezza lessicale di un gruppo di studenti italiani di spagnolo LS a livello universitario. Partendo dai primi studi finalizzati all’elaborazione del Proyecto Panhispánico de Disponibilidad Léxica dedicati a ispanofoni nativi, dai progetti pionieristici di Carcedo (2000c) e Samper Hernández (2002) che si sono occupati di apprendenti non nativi di spagnolo ed infine dai contributi più recenti di Sánchez-Saus (2011), Hidalgo (2017b) e Del Barrio y Vann (2018), è stato elaborato un test che ha permesso di svolgere un’indagine linguistico-statistica trasversale e longitudinale del lessico disponibile del campione. Suddetto consisteva nella prova standardizzata di disponibilità lessicale, in cui si presentano alcuni stimoli semantici per attivare i vocaboli che i soggetti intervistati associano a tali input. Inoltre, nello stesso test è stata inserita un’ulteriore prova destinata alla misurazione e alla valutazione della ricchezza lessicale, dove era richiesta la stesura di un breve testo narrativo che è stato analizzato in base a indici standard (Read, 2000). L’esperimento, proponendosi come un progetto innovativo che tratta il complesso fenomeno della competenza lessicale, ha conciliato due metodologie complementari capaci di determinare il livello di apprendimento e la conoscenza del vocabolario spagnolo dei partecipanti. I risultati emersi dalle analisi quantitativa, qualitativa e comparativa dei dati hanno condotto a nuove ed interessanti riflessioni derivanti dall’unione della disponibilità e della ricchezza lessicale per la prima volta in un unico studio. In più, gli approcci trasversale e longitudinale hanno portato a rinnovare il modus operandi di ricerca applicato finora in questo ambito, improntato solamente su studi trasversali.
This thesis, framed within the areas of Applied Linguistics and Didactics of Spanish, investigates lexical availability and lexical richness in a group of Italian university students learning Spanish as a FL. The theoretical framework consists of Proyecto Panhispánico de Disponibilidad Léxica, involving native Spanish speakers, pioneering works of Carcedo (2000c) and Samper Hernández (2002) that dealt with non-native Spanish learners and the latest findings of Sánchez-Saus (2011), Hidalgo (2017b) and Del Barrio y Vann (2018). It was designed an associative test which allowed to conduct a linguistic-statistical survey on the available lexicon of informants through a cross-sectional and longitudinal analysis. This test focuses on the vocabulary produced by respondents when prompted with stimuli and collects their mental lexicon. In addition, it was included a further test for measuring and evaluating lexical richness, which required the writing of a short narrative text that was examined on the basis of standard indexes (Read, 2000). The experiment aims to be an innovative project which deals with the complex phenomenon of lexical competence, combining two complementary methodologies capable of ascertaining the participants’ language proficiency and knowledge of Spanish vocabulary. Results of the quantitative, qualitative and comparative analysis of data led to significant new considerations arising from the combination of lexical availability and lexical richness merged for the first time in a single study. Moreover, the transverse and longitudinal approaches brought about a renewal of the research method in this field, which so far was solely based on cross-sectional studies.

Esta tesis, que quiere ser transdisciplinaria, combinando las ciencias del lenguaje, las ciencias de la educación y la sociolingüística, se centra en cuatro áreas principales: la política del plurilingüismo en las instituciones educativas, el aprendizaje y la adquisición de LE (el Francés Lengua Extranjera: FLE, y el Español Lengua Extranjera: ELE), el tratamiento del error y el feedback correctivo (FC) en la producción escrita, así como las pistas de optimización didáctica para promover la educación plurilingüe y el FC. Los resultados de este trabajo de investigación muestran que, a nivel nacional, el objetivo del plurilingüismo en las instituciones educativas está muy lejos de ser alcanzado en Francia y en España, como lo demuestra el análisis de las cifras y las estadísticas publicadas por los dos Ministerios de Educación en el año académico 2014-2015, dejando ver una situación poco ventajosa del francés en España y del español en Francia frente al dominio del inglés, aunque es innegable que el ELE presenta en este sentido mejores resultados que el FLE. A nivel local, es decir en el marco del aula, la investigación-acción realizada en clase de FLE y de ELE se ha centrado en el análisis de diferentes tipos de FC escrito (directo, indirecto, reformulativo, metalingüístico, electrónico y mixto) a través de un proceso en tres etapas: redacción / comparación con el FC / reescritura. Se trataba de descubrir el impacto de cada FC experimentado en ambos sistemas educativos y de realizar una síntesis de la retroalimentación correctiva más eficaz en Francia y en España, con el fin de desarrollar el estadio de interlengua de los alumnos. Los datos y los resultados de la investigación muestran que la práctica de algunos tipos de FC, según diferentes modalidades de agrupamiento de aprendices (individual o por parejas), ha tenido un impacto directo en el proceso de aprendizaje / adquisición de la LE, tales como el FC directo en los alumnos de Secundaria de FLE y de ELE, el FC metalingüístico en tándem en los aprendices hispanófonos de Bachillerato, el FC mixto en los aprendices francófonos de Instituto y los estudiantes de ambos países. En cambio, otros FC no han provocado la asimilación de nuevos conocimientos por parte de los aprendices; a saber el FC indirecto, sobre todo en los alumnos españoles de ESO, el FC metalingüístico en tándem en los aprendices francófonos de Instituto, el FC metalingüístico individual en los aprendices de habla español, el FC indirecto en los estudiantes de ambos lados de los Pirineos. Esto ha dado lugar a que numerosas reglas gramaticales permanezcan todavía inertes. De ahí, la presencia recurrente de errores no rectificados en la producción escrita de los alumnos. El estudio finaliza proponiendo algunas recomendaciones susceptibles de ser ampliadas o modificadas, con el fin de lograr el "plurilingüismo" tan proclamado por las instancias europeas y optimizar el FC en clase de FLE y de ELE.

Cette thèse qui se veut transdisciplinaire, alliant les sciences du langage, les sciences de l'éducation et la sociolinguistique, se centre sur quatre axes principaux : la politique du plurilinguisme dans les institutions éducatives, l'apprentissage et l'acquisition des LE (le Français Langue Etrangère : FLE, et l'Espagnol Langue Etrangère : ELE), les erreurs et le feedback correctif (FC) à l'écrit, les pistes d'optimisation didactique pour promouvoir l'éducation plurilingue et le FC. Les résultats de ce travail de recherche montrent que, à l'échelle nationale, l'objectif du plurilinguisme dans les institutions éducatives est très loin d'être atteint en France et en Espagne, comme en témoigne l'analyse des chiffres et des statistiques publiés par les deux Ministères de l’Éducation Nationale durant l'année académique 2014-2015, laissant transparaître la situation peu avantageuse du français en Espagne et de l'espagnol en France face à la prédominance de l'anglais, bien qu'il soit indéniable que l'ELE présente de bien meilleurs résultats que le FLE. A l'échelle locale, c'est-à-dire au niveau de la classe, notre travail de recherche-action autour du FLE et de l'ELE s'est centré sur l'analyse de différents types de FC expérimentés à l'écrit (direct, indirect, reformulatif, métalinguistique, électronique et mixte) à travers une démarche en trois étapes : rédaction / comparaison avec le FC / réécriture. L'objectif était de découvrir l'impact de chacun des FC à l'étude dans les deux systèmes éducatifs considérés, et de réaliser une synthèse de la rétroaction corrective s'avérant la plus efficace en France et en Espagne, en vue de faire évoluer le stade d'interlangue des apprenants. Les données et les résultats de la recherche montrent que la pratique de certains types de FC, suivant différentes modalités de regroupement d'apprenants (individuel ou en binôme), a eu une incidence directe dans le processus d'apprentissage / acquisition de la LE, tels que le FC direct chez les collégiens de FLE et d'ELE, le FC métalinguistique en binôme chez les lycéens espagnols, le FC mixte chez les lycéens français et les étudiants des deux pays. En revanche, d'autres FC n'ont pas entraîné l'assimilation de nouvelles connaissances par les apprenants, à savoir le FC indirect, surtout chez les collégiens hispanophones, le FC métalinguistique en binôme chez les lycéens francophones, le FC métalinguistique individuel chez les lycéens hispanophones, le FC indirect chez les étudiants de part et d'autre des Pyrénées. C'est ainsi que de nombreuses règles grammaticales restent encore inertes. D'où la présence récurrente d'erreurs non rectifiées dans les productions écrites de tous les apprenants. L'étude conclut en proposant quelques recommandations susceptibles d'être étoffées, voire modifiées, ayant pour finalité le « plurilinguisme » tant proclamé par les instances européennes et l'optimisation du FC en classe de LE
This thesis, which aims at adopting a transdisciplinary approach by combining the Language Sciences, Education Sciences and Sociolinguistics, focuses on four main ranges: the politics of the plurilingual education, the learning and acquisition of a foreign language (French as a Foreign Language: FFL, Spanish as a Foreign Language: SFL), error treatment and corrective feedback (CF) in writing, as well as the didactic optimization tools directed to promoting both plurilingual education and CF. The results of this piece of research show that the nationwide goal of fostering plurilingualism is far from being reached in France as well as in Spain, as evidenced by the figures and statistics issued by both respective Ministries of Education for the academic year 2014-2015, which attest to the underprivileged status of the French language in Spain and that of the Spanish language in France compared with English language, even though it cannot be denied that SFL teaching delivers, in this regard, better results than FFL teaching. On a local scale, at the classroom level, the methodological approach of action-research carried out in different FFL/SFL classrooms has focused on the analysis of different types of written corrective feedback (direct, indirect, reformulative, metalinguistic, electronic and mixed) throughout a process split into three phases: writing task / comparison between the aforementioned task and the provided corrective feedback / rewriting task. The objective sought was both to bring to light the impact of CF on both education systems and to elaborate an abridgment of the most effective CF in France and Spain in order to develop the students' interlanguage stages. As shown by the data and results of the research, the practice of some types of CF, according to different classification methods for learners (individual, pairs), has had a direct impact on the foreign language learning/acquisition process through the direct CF in secondary school students (both FFL and SFL), the metalinguistic CF in tandem partners amongst Spanish-speaking students undertaking the Spanish Baccalaureate and the mixed CF amongst the French-speaking high school students and the students of both countries. Nevertheless, other types of CF have been proven to be ineffective to insure assimilation by learners such as the case of the indirect CF, especially amongst secondary-school Spanish students, the metalinguistic CF in tandem partners amongst French-speaking high school students, the individual metalinguistic CF amongst Spanish-speaking learners and the indirect CF amongst students on both sides of the Pyrenees. This has brought about the specific conservatism of plenty of grammar rules. Hence, the recurring presence of errors left uncorrected by students in their writing tasks. The study concludes with some recommendations liable to being broadened or modified, with the objectives of reaching the much proclaimed "plurilingualism" by the European institutions and of optimizing the CF in the FFL/SLF classrooms
Esta tesis, que quiere ser transdisciplinaria, combinando las ciencias del lenguaje, las ciencias de la educación y la sociolingüística, se centra en cuatro áreas principales: la política del plurilingüismo en las instituciones educativas, el aprendizaje y la adquisición de LE (el Francés Lengua Extranjera: FLE, y el Español Lengua Extranjera: ELE), el tratamiento del error y el feedback correctivo (FC) en la producción escrita, así como las pistas de optimización didáctica para promover la educación plurilingüe y el FC. Los resultados de este trabajo de investigación muestran que, a nivel nacional, el objetivo del plurilingüismo en las instituciones educativas está muy lejos de ser alcanzado en Francia y en España, como lo demuestra el análisis de las cifras y las estadísticas publicadas por los dos Ministerios de Educación en el año académico 2014-2015, dejando ver una situación poco ventajosa del francés en España y del español en Francia frente al dominio del inglés, aunque es innegable que el ELE presenta en este sentido mejores resultados que el FLE. A nivel local, es decir en el marco del aula, la investigación-acción realizada en clase de FLE y de ELE se ha centrado en el análisis de diferentes tipos de FC escrito (directo, indirecto, reformulativo, metalingüístico, electrónico y mixto) a través de un proceso en tres etapas: redacción / comparación con el FC / reescritura. Se trataba de descubrir el impacto de cada FC experimentado en ambos sistemas educativos y de realizar una síntesis de la retroalimentación correctiva más eficaz en Francia y en España, con el fin de desarrollar el estadio de interlengua de los alumnos. Los datos y los resultados de la investigación muestran que la práctica de algunos tipos de FC, según diferentes modalidades de agrupamiento de aprendices (individual o por parejas), ha tenido un impacto directo en el proceso de aprendizaje / adquisición de la LE, tales como el FC directo en los alumnos de Secundaria de FLE y de ELE, el FC metalingüístico en tándem en los aprendices hispanófonos de Bachillerato, el FC mixto en los aprendices francófonos de Instituto y los estudiantes de ambos países. En cambio, otros FC no han provocado la asimilación de nuevos conocimientos por parte de los aprendices; a saber el FC indirecto, sobre todo en los alumnos españoles de ESO, el FC metalingüístico en tándem en los aprendices francófonos de Instituto, el FC metalingüístico individual en los aprendices de habla español, el FC indirecto en los estudiantes de ambos lados de los Pirineos. Esto ha dado lugar a que numerosas reglas gramaticales permanezcan todavía inertes. De ahí, la presencia recurrente de errores no rectificados en la producción escrita de los alumnos. El estudio finaliza proponiendo algunas recomendaciones susceptibles de ser ampliadas o modificadas, con el fin de lograr el "plurilingüismo" tan proclamado por las instancias europeas y optimizar el FC en clase de FLE y de ELE

The first definitive haematopoietic stem cells (HSCs) produced during embryonic development are generated from a specialised subset of endothelial cells known as haemogenic endothelium. Recently, it was reported that Gata3 plays a dual role in the development of sympathetic nervous system and haematopoietic system. In fact, Gata3 has proven to be crucial for the production of HSCs through regulation of catecholamine production from the co-developing sympathetic nervous system. Also, it was recently shown that Gata3 is expressed in the haemogenic endothelium and haematopoietic progenitor cells. Here, I will specifically examine the role of Gata3 in the production of HSCs; if it is expressed and plays a role in the precursors from which HSCs arise. Using a Gata3-GFP reporter mouse line, we found that Gata3 is expressed in various cell types in the HSCs microenvironment, including mesenchymal cells, endothelial cells, haematopoietic cells and sympathetic nervous system, and this expression was stage dependant. In the endothelial cells, we have found that the haemogenic endothelium activity is enriched in Gata3 expressing cells. Within the haematopoietic cells, we have found that Gata3 marks a specific stage along the developmental pathway towards the generation of definitive haematopoietic stem cells, and that Gata3 expressing haematopoietic cells are enriched for the most immature and stem cell like progenitors. Moreover, Gata3 will be specifically knocked out in haemogenic endothelial cells to determine whether it plays an essential role in the production of HSCs from the endothelium using the Vec-Cre system. We found that Gata3 within the haemogenic endothelium plays a major role in haematopoietic progenitors formation, and possibly haematopoietic stem cell formation. Finally, we used molecular assay (RNA seq) to identify the role of Gata3 in the haematopoietic stem cell microenvironment and found that Gata3 plays a major role in the development and differentiation of various cells and systems, and implicated Gata3 as cell cycle regulator. In summary, we found that Gata3 expressing cells is enriched for haemogenic endothelium, crucial for the haematopoietic progenitors formation, plays and important role in endothelial to haematopoietic transition, and plays a key developmental role in both haematopoietic stem cell and its microenvironment.

El objetivo de esta monografía es tratar de determinar en qué medida y de qué manera cuatro manuales didácticos suecos de español como lengua extranjera (ELE), usados en la enseñanza en el nivel de bachillerato, tratan aspectos pragmáticos. Además, evaluaremos el potencial y la relevancia de la información metapragmática y las actividades relacionadas a los aspectos pragmáticos para el proceso de adquisición de una competencia tanto metapragmática como pragmática. En este estudio se parte de la noción de la competencia pragmática como una destreza orientada a saber crear y comprender significados en la interacción de manera eficaz (Thomas, 1995), que supone, más que los conocimientos lingüísticos en una interacción intercultural, los conocimientos extralingüísticos (cf. Bravo, 2005). La hipótesis de partida de este trabajo postula que los manuales no explican a fondo por qué cierto lenguaje se utiliza en ciertos contextos y que el contenido pragmático sería poco variado y difícil de asimilar y que los ejercicios no estarían diseñados principalmente para desarrollar la competencia pragmática. Hasta cierta medida se puede decir que los resultados de esta investigación confirman la hipótesis: los manuales podrían efectivamente ser más exhaustivos en cuanto a los temas que abarcan, asimismo podrían variar y explicar más a fondo aquellos temas. No obstante, parece haber un esfuerzo de incorporar actividades comunicativas e información extralingüística, sin embargo, hace falta una conceptualización y progresión en cuanto a cómo tratar estos temas como el propósito principal. Ni siquiera se ofrecen en las guías del profesor modelos didácticos o información adicional, y por lo general, no se combina la información metapragmática en los manuales con actividades complementarias que pretenden desarrollar las destrezas comunicativas.
The purpose of this paper is to try to determine to what extent and in what way four Swedish textbooks on Spanish as a foreign language (SFL) treat pragmatic aspects, as well as to evaluate the potential and relevance of the metapragmatic information and activities related to pragmatic aspects provided by the textbooks, for the development of pragmatic awareness and competence in Spanish. This study parts from the notion of pragmatic competence as a skill of knowing how to create and understand meanings in interaction effectively (Thomas, 1995), which in intercultural interaction probably requires extra-linguistic knowledge more than language skills (cf. Bravo, 2005). The hypothesis postulated at the beginning of the study was that the manuals would not fully explain why certain language is being used in certain contexts, that the pragmatic content would be scarcely varied and rather difficult to assimilate and that the exercises would not be designed primarily to develop a pragmatic competence. To some extent it can be said that the hypothesis is confirmed: the manuals could have been more comprehensive in terms of the topics covered, they could also have varied and explained those issues further. Despite the fact that there seems to be an effort to incorporate extra-linguistic information and communicative activities, the results indicate that there is a lack of emphasis on or progression on how to treat these issues. For example, there are no didactic models or suggestions in the teacher’s guide, nor is additional information provided elsewhere; usually the metapragmatic information is not combined with any activities, and the activities that aim to develop communicative skills are not combined with further metapragmatic information.

碩士
國立臺灣科技大學
營建工程技術學系
81
This study, based on the "least-void-ratio" concept of concrete proportional method, presents the experimental results the properties of high-strength concrete with cold-pelletized lightweight fly-ash aggregates. The experimental variables, are selected to investigate their effects on the compressive strength, unit weight and etc., include substitution of cement silica fume, addition of steel fiber, water-cement ratio and of mortar. In addition, the splitting test, flexural test and fracture test were also conducted for the proportional ratio of high-strength light weight concrete which gives the highest compressive strength. The fracture test contains the fracture toughness, stress intensity factor, load-deflection curve and CMOD (Crack Mouth Opening Displacement) curve. It is shown that the substitution of cement with silica fume increases the compressive strength, but adversely decrease the values of splitting strength, flexural strength and fracture toughness. On the other hand, the addition of steel fiber does not alter a negligible variation of the compressive strength, but obviously improves the splitting strength, flexural strength and toughness. On fracture properties, the high-strength lightweight cold- pelletized fly-ash aggregate concrete shows an apparent tendency size effects, from which the fracture toughness ranged from 34 to 52 N/m and stress intensity factor ranged from 949000 to 1120000 N/m1.5 were calculated. Those values of stress intensity factor found to be comparative to those of normal concretes.

碩士
國立高雄應用科技大學
機械與精密工程研究所
104
A compact projection system, using separated RGB LEDs as light sources, is designed mainly by cementing fly-eye arrays on the surfaces of X-cube prism, which is helpful for not only shrinking the system volume but also increasing the energy efficiency by reducing the reflection loss on optical surfaces. For constructing the initial first-order design of the illumination component, the focal lengths and dimensions of corresponding elements are solved by the optical invariant principle. The next step is to compare the influence on the uniformity for condensers with the same focal length but different lens shapes. Thirdly, condensers are optimized and analyzed for each primary colors. For imaging component, two types of telecentric lenses with purely spherical surfaces are designed. One design is not offset but the other provides offset ability to correct the keystone distortion. Eventually, both illumination and imaging parts are combined and the overall illumination uniformity on the projection screen is discussed.

碩士
國立師範大學
生物學研究所
82
1.Electro-microscopic examination showed that the rhabdomeres of retinular cells (R1-6)in the medial-dorsal region of the left compound eye of Dacus dorsalis Hendel twist along their length. Again as in Musca and Calliphora, the two groups of rhabdomeres, R1-3 and R4-6, twist in mirror-image directions. As the twisting degree was concerned, the rhabdomeres could be divided into three regions; (1)region Ⅰabout 0-84±5μｍ below the crystalline cone, twisting rate between 0.226-0.464°/μｍ.(2) region Ⅱ: about 84-110±5μｍ, twisting rate between 1.602-5.28 °/μｍ.(3)region Ⅲ:about 110-160±5μｍ, twisting rate between 0.09--.659°/μｍ. 2.Intracellular recordings were made from the medial-dorsal region of the Dacus dorsalis Hendel. Spectral sensitivity curve showed that the maximun absorbing band is near the UV band (λ max=349nm), and the second is near the green band (λmax=460nm). Polarization sensitivity values averaged 1.1-1.4. Divided by polarization sensitivity θmax, they had three pattern:(1)θmax =3.83°;(2)θmax=152.53°;(3)θmax=48.19°。

Num momento em que o estudo de uma segunda língua é tão indispensável para o mundo do trabalho e para a valorização pessoal, é necessário repensar uma forma eficaz e interessante de aprendizagem da mesma. Logo, estando nós numa época de apogeu das novas tecnologias e onde é recorrente o aparecimento de metodologias cada vez mais modernas, torna-se imprescindível renovar também os métodos utilizados. É, por isso, neste contexto que surge esta investigação, a qual pretende apresentar uma proposta válida e fundamentada para o ensino-aprendizagem de uma língua estrangeira (LE). Partindo de uma perspetiva histórica, nela analisar-se-á, essencialmente, a importância e os benefícios da utilização dos jogos como método de aprendizagem de vocabulário, tendo, para isso, como base a prática pedagógica supervisionada, realizada numa escola pública do concelho de Braga. Assim, nesta investigação será defendida a necessidade de promover o caráter lúdico e polivalente dos jogos, os quais permitem introduzir, rever e praticar todo e qualquer tipo de conteúdo de uma forma mais motivadora e interessante. Além disso, comprovar-se-á igualmente a multiplicidade de jogos que podem ser utilizados, sendo, ainda, apresentadas algumas propostas para diferentes temas. Por fim, descrever-seão os resultados e conclusões obtidos, após a implementação do estudo.
Hoy en día el estudio de una segunda lengua es indispensable para el mundo del trabajo y para la valoración personal, por lo que se hace necesario repensar una forma eficaz e interesante de aprenderla. Además, en una época álgida para las nuevas tecnologías y en la que es recurrente la aparición de metodologías cada vez más modernas, es imprescindible renovar también los métodos utilizados. En este contexto surge esta investigación, la cual pretende presentar una propuesta válida y fundamentada para la enseñanza-aprendizaje de una lengua extranjera (LE). Partiendo de una perspectiva histórica, en estas páginas se analizarán, sobre todo, la importancia y los beneficios de la utilización de los juegos como método de aprendizaje de vocabulario, utilizando, para eso, la Práctica Pedagógica Supervisionada (PPS), realizada en un colegio de Braga. Así, será defendida la necesidad de promover el carácter lúdico y polivalente de los juegos, los cuales permiten introducir, revisar y practicar cualquier tipo de contenido de una forma más motivadora e interesante. Además, se comprobará igualmente la multiplicidad de juegos que pueden ser utilizados, presentando a mayores algunas propuestas para diferentes temas. Finalmente, serán descritos los resultados obtenidos y las conclusiones alcanzadas, después de la implementación del estudio.
At a time when learning a second language is so essential for professional and personal development, it is mandatory to rethink second-language learning processes more effectively. As we live in an era in which new technologies abound and more modern teaching methodologies constantly arise, it is also indispensable to modernize those very teaching methods themselves. It is, thus, in this context that this research arises, as it aims at giving a valid and reasoned proposal to teach and learn a foreign language (FL). From a historical perspective, I will revise the importance and the benefits of using games as a method of vocabulary learning; this revision will be backed up by our teaching experiences as performed in a public school of Braga. Thus, in this research will be defended the urge to promote the playful and multipurpose function of using games in teaching as they are able to introduce, review and practice different sorts of linguistic content in more motivating and interesting ways. Moreover, the multifariousness of games that can be used in teaching will also be tested and some proposals for different subjects will be presented. After implementing the study, some conclusions and final results will be described.

Este relatório assume como finalidade analisar e avaliar as potencialidades das tecnologias da informação e comunicação (TIC), com especial enfoque nas ferramentas da Web 2.0, para a criação de ambientes de aprendizagem colaborativa e construtiva. Para isso, parte-se da implementação de um projeto eTwinning levado a cabo com mais sete escolas europeias e desenvolvido, em Portugal, no Agrupamento de escolas Ibn Mucana, com alunos do 9º ano, no âmbito da disciplina de Espanhol Língua Estrangeira (ELE). O projeto implementado intitula-se Europa estudia español e encontra-se centrado na vida escolar dos alunos e nas obras literárias, teatrais e cinematográficas que integram o currículo dos diversos participantes. Pretende-se, com este relatório, alcançar um melhor conhecimento do processo de ensino e aprendizagem, no que se refere ao impacto da implementação de um projeto colaborativo eTwinning e do seu potencial na promoção da motivação e na melhoria dos resultados escolares. No primeiro capítulo, dá-se conta da pesquisa bibliográfica relativa a campos de conhecimento que possam oferecer contributos válidos para fundamentar e orientar a análise e avaliação das potencialidades das TIC. No segundo capítulo apresenta-se e descreve-se o programa de intervenção, o espaço escolar onde foi realizada a Prática de Ensino Supervisionada (PES) e faz-se uma caracterização das turmas em que foram lecionadas as aulas práticas e, finalmente, reflete-se sobre o impacto da sua implementação.

Dissertação de mestrado em Espanhol como Língua Segunda / Língua Estrangeira
La participación en las actividades de producción oral es uno de los mayores problemas a los que se enfrenta el profesor de español. El estudio de los factores afectivos envueltos en esta problemática es relativamente reciente en lo que se refiere a la enseñanza-aprendizaje de una lengua extranjera, pero ya ha mostrado que la ansiedad ante su estudio y la motivación, así como la forma en que ambas se relacionan, se encuentran en la base de la misma. La investigación nos muestra que los factores grupales y la figura del profesor juegan un importante papel a la hora de manejar estos dos factores afectivos en el aula, ayudándonos a aumentar la motivación y disminuir la ansiedad. Este informe de prácticas pretende arrojar luz sobre el tipo de técnicas y estrategias que se pueden llevar a cabo en la clase de ELE para fomentar los factores grupales y mejorar la actuación del profesor en el aula, de forma que consigamos disminuir la ansiedad y promover la motivación para que los alumnos participen más en clase. Para ello, la presente investigación se encuadra dentro de una Investigación-Acción, con la consecuente reflexión sobre la práctica educativa que esta conlleva, utilizando como base metodológica el Enfoque Comunicativo Mediante Tareas. La intervención fue realizada en un centro de lenguas en dos cursos diferentes con alumnos portugueses adultos. Los resultados fueron positivos y fueron extraídos de dos fuentes diferentes: el diario de la profesora y un cuestionario respondido por los alumnos a través del cual se pretendió saber si creían que participaban con menos ansiedad en las actividades de producción oral propuestas en el aula al final de los cursos y qué tipo de actividades y estrategias consideraban que habían sido de más ayuda.
One of the largest challenges faced by a spanish teacher is getting students to engage in activities of oral production. The study of affective factors involved in these kind of issues is relatively recent, in what regards to the teaching-learning of a foreign language, but has already shown that anxiety towards its study and motivation, as well as their inter-relation, are at the basis of these challenges. Investigation reveals that group factors and the teacher's stance both play an important role when it comes to handling these two affective factors in class, helping increase motivation and reduce anxiety. This report intends to throw some light over the kind of techniques and strategies that can be used in a Spanish-Foreign-Language class to nurture the group factors and improve the performance of the teacher, in a way as to reduce anxiety and promote motivation so that students take a more active role in class. The present investigation is thus framed within Investigation-Action, with the resulting reflexion on educative practice, using Task-based Language Learning as base methology. The intervention was undertaken in a language center, in two different courses, with adult portuguese students. The results were positive and extracted from two different sources: the teacher's journal and a questionnaire administered to the students, with the intention of assessing whether they believed to be participating with less anxiety in the proposed oral production activities, and what kind of activities and strategies they considered to have been the most helpful.

A língua portuguesa ocupa atualmente um lugar de destaque no mundo global. É a língua mais falada no hemisfério sul e uma das cinco línguas mais faladas no mundo, com cerca de 263 milhões de falantes. Em 2050 serão de 390 milhões de falantes nos seis continentes e 490 milhões até 2100 (Atlas da Língua Portuguesa, 2016). De acordo com a World Internet Statistics (2016) o português é também a quinta língua mais usada na Internet, com cerca de 154.5 milhões de utilizadores, à sua frente ficam o Inglês (948.6), o chinês (751.9), o espanhol (277.1) e o árabe (168.4). O Brasil aparece em quarto lugar com o maior número de utilizadores de Internet (139.1 milhões). A importância da língua portuguesa como fator de afirmação no mundo global estende-se, nos dias de hoje, aos mais diversos domínios, como meio privilegiado de comunicação, saber e cultura, assumindo um poder geoestratégico indiscutível. O português tem sido uma língua de contacto entre povos e civilizações distintas. Como resultado, é a língua oficial de nove países (Portugal, Brasil, Angola, Moçambique, Guiné-Bissau, Cabo Verde, São Tomé e Príncipe e, mais recentemente, Guiné-Equatorial) e a segunda oficial de Timor-Leste e Macau, exibindo, assim, a vasta diversidade de contextos linguísticos, políticos e geográficos. No entanto, o seu estatuto como Língua segunda e estrangeira difere de contexto para contexto. É, assim, crucial perceber esta modificação ao nível de seu uso em contextos linguísticos, geográficos e políticos distintos. É, nesse sentido, um desafio entender como a pesquisa atual no campo do ensino e aprendizagem das línguas se aplica à diversidade cultural das audiências alvo e se adapta às realidades diferentes e complexas, refletindo as suas limitações, conflitos e exigências, na medida em que a língua (s) e a cultura (s) estão ligadas inevitavelmente uma(s) à(s) outra(s). Pelas razões expostas, pretende-se determinar os contextos, as políticas e as abordagens que presidem ao ensino do português no estrangeiro, no sentido de clarificar como se organiza este tipo de ensino na Europa e em África, em particular, nos Países Africanos de Língua Oficial Portuguesa (PALOP), mediante a aplicação de um inquérito aos professores e alunos do EPE nos contextos europeu e africano, individualizando o domínio da aprendizagem e ensino do português como língua segunda e estrangeira, em contextos políticos, geográficos e linguísticos múltiplos. Constatámos que os desafios dos sistemas de ensino e realidades diferentes apresentam algumas diferenças, mas também se debatem com problemas semelhantes. Há ainda um longo caminho a percorrer em virtude das dificuldades e das muitas ineficiências na execução do EPE nos diferentes contextos.
Today, the portuguese language has a proeminent place in the global world, being one of the five most widely spoken languages, it is spoken by approximately 263 million speakers in the six continents. The projection of about 390 million in 2050 and of about 490 million until 2100 (Atlas da Língua Portuguesa, 2016), suggests a trend towards an increase in the number of speakers. According to the World Internet Statistics (2016) Portuguese is also the fifth most used language on the Internet, with 154.5 million users, ahead of them are English (948.6), Chinese (751.9), Spanish (277.1) and Arabic (168.4). Brazil appears in fourth place with the largest number of Internet users (139.1 million). The importance of Portuguese as a factor of affirmation in the global world nowadays extends to the most diverse domains, as a privileged means of communication, knowledge and culture, assuming an undisputed geostrategic power. The portuguese language has been a language of contact between peoples and civilizations, holding the premise of unity and diversity simultaneously. As a result, it is the official language of eight countries (Portugal, Brazil, Angola, Mozambique, Guinea-Bissau, Cape Verde, São Tomé e Príncipe, East Timor), displaying a huge diversity of linguístic, political and geographical contexts. However, its status differs from context to context (within different contexts). In Europe is the result of Multilinguistic policies within the EU. It is crucial to realize this modification at the level of its use, referring to established approaches in teaching a Language Two (Second Language) and a Foreign language, aplying the cutting edge teaching theories to these so specific and multiple contexts. It's a challenge also to realize how current research within the learning/ teaching of languages applies to cultural diversity of the target audience and adapts to different and complex realities, reflecting on their limitations, conflicts and needs, to the extent that language (s) and culture (s) are linked inevitably one to the other. For these reasons, the following research aims to display the contexts, current policies and learning and teaching approaches in the Portuguese Teaching Abroad in Europe and in Africa, in particular, in the Portuguese Speaking Countries (PALOP), individualizing the learning and teaching of the Portuguese as a second and foreign language in multiple political, geographical and linguistic contexts. We have found that the challenges of different education systems and realities present some differences, but also face similar problems. There is still a long way to go due to the difficulties and many inefficiencies in the implementation of EPE in different contexts.

Esta dissertação pretende centrar-se no ensino da Língua Portuguesa como língua segunda ou estrangeira através da aplicação dos conceitos dos jogos na educação. Numa primeira parte pretende-se explorar a gamification e verificar as diversas formas existentes da mesma. Num segundo momento, será analisada a sua aplicabilidade dentro e fora de uma sala de aula, verificando se é possível aplicar em todas situações ou não e de que maneira esta pode facilitar o ensino e promoção da Língua Portuguesa. Em terceiro lugar será feita uma análise a estudos realizados previamente relativa à realidade dos assistentes de Língua Portuguesa em França. Com a análise deste estudo pretende-se descobrir quais as dificuldades dos assistentes nas salas de aula de Português como língua segunda ou estrangeira. Por último será elaborado um plano de aula, tendo como base os mecanismos dos jogos e com o objetivo de encontrar uma resposta para as dificuldades dos professores/assistentes bem como dos alunos.
This dissertation focuses on teaching the Portuguese language as a second or foreign language through the application of concepts and mechanisms found in games and applied to education. In a first moment, I intend to explore the concept of gamification and analyze its various forms. Secondly, it will be examined if this method/concept is applicable inside and outside a classroom, verifying if it is possible to apply it in different situations and in what way this can facilitate the teaching and promotion of the Portuguese Language. Thirdly, an analysis will be made of a previous 5 study about the reality of the assistants of Portuguese Language in France. This study intends to find out the difficulties of assistants in Portuguese classrooms as a second or foreign language. Finally, a lesson plan will be elaborated, based on mechanisms that exist in games in order to find an answer to the difficulties of the teachers / assistants as well as the difficulties of the students.