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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
361

Cartographie fine de la recombinaison, analyse des séquences locales et étude du déséquilibre de liaison chez le blé tendre (Triticum aestivum) / High-resolution mapping of crossover events in the hexaploid wheat genome

Darrier, Benoît 08 December 2016 (has links)
Mieux connaitre les facteurs qui gouvernent l’apparition des évènements de recombinaison (crossing-overs ; CO) chez le blé tendre (Triticum aestivum L.) est primordial car ce processus est l’outil principal du sélectionneur pour permettre le brassage de la diversité génétique et l’introgression de régions d’intérêt dans des variétés agronomiques. L’utilisation de techniques de cytogénétique développées sur l’orge a permis de comparer la mise en place de la synapse lors de la méiose chez des lignées de blé tendre délétées de tout ou partie du bras long du chromosome 3B et qui avaient été préalablement montrées comme présentant un nombre de chiasmas réduit par rapport à la variété euploïde. Les analyses cytogénétiques couplées à des études bioinformatiques de la séquence montrent que le synapsis a lieu quasiment normalement chez les mutants et que la délétion de certains gènes connus comme impactant le déroulement de la méiose pourrait expliquer le phénotype observé. De plus, le développement de ressources génomiques (SNP, séquence) à destination des sélectionneurs a permis la réalisation de cartes génétiques haute densité des 21 chromosomes ancrées sur la séquence du génome. Tous les chromosomes montrent le même profil de recombinaison avec un accroissement dans les parties distales et une réduction drastique dans les parties centromériques et péri-centromériques. L’exploitation de plus de 250 CO localisés dans des fenêtres de moins de 25 kb sur le chromosome 3B utilisé comme modèle pour l’étude de l’impact de la séquence sur la recombinaison, montre que les profils de recombinaison ancestrale et actuelle sont conservés et que les CO ont lieu préférentiellement dans les parties promotrices des gènes exprimés en méiose ce qui suggère que la conformation chromatinienne influence la recombinaison. Finalement, ces données ont aussi été l’opportunité de détecter des motifs liés à la recombinaison qui présentent des similarités avec celui ciblé par la protéine PRDM9 qui conduit à la recombinaison chez l’humain. Cela suggère que les mécanismes de contrôle de la recombinaison sont conservés chez les eucaryotes. / Better knowledge of the factors that drive recombination (crossovers; COs) in bread wheat (Triticum aestivum L.) is of main interest since this process is the main tool allowing breeders to admix the genetic diversity and to introgress regions of interest in agronomic varieties. We used cytogenetic techniques previously developed on barley to compare the establishment of synapsis during meiosis in deletion lines missing part or whole of the long arm of chromosome 3B of bread wheat and which were previously shown as having a reduced chiasmata number compared to euploid varieties. Cytogenetic analysis combined with bioinformatics studies showed that the synapsis occurs almost normally in mutants and that deletion of some genes known to impact meiosis behavior may explain the observed phenotype. In addition, development of genomic resources (SNPs, sequence) for wheat breeders allowed simultaneous elaboration of high density genetic maps for the 21 chromosomes anchored on genome sequence. All chromosomes present the same recombination pattern with an increase of recombination in the distal parts and reduction in centromeric/pericentromeric regions of the chromosomes. Analysis of more than 250 COs mapped in windows lower than 25kb located on chromosome 3B used as model to study the impact of sequence features on recombination showed that current and ancestral recombination patterns are conserved and that COs preferentially occur in the promoter part of gene expressed in meiosis suggesting that chromatin conformation impacts recombination. Finally, these data were the opportunity to detect recombination-associated motif which presents similarities with the motif targeted by the PRDM9 protein driving recombination in human. This suggests that the control of recombination mechanisms is conserved among eukaryotes.
362

Exploring studio-based higher education for T-shaped knowledge workers, case LAB studio model

Heikkinen, K.-P. (Kari-Pekka) 02 January 2018 (has links)
Abstract Speed of information, uncertainty and complexity are increasing in the work-life of the knowledge worker. In addition, solving complex and wicked global problems require cooperation skills as well as ability to learn in collaboration across the disciplines, meaning skills in crossing boundaries. These requirements set new challenges for educating knowledge workers in higher education. Metaskills, such as learning by utilising networks, communication and critical thinking, have become as essential as discipline-specific skills. Metaskills combined with discipline-specific skills are called T-shaped skills. Individuals possessing these skills, so-called T-shaped professionals, are exposed to the experience and the knowledge of other disciplines and thus are recognised as carrying the skills for crossing boundaries. This dissertation examines how a Finnish studio-based pedagogical approach to bachelor education, the LAB Studio Model (LSM), contributes to the education of boundary crossing competence. This qualitative dissertation utilises exploratory as well as design research as its research approach and contains four original publications. First, the characteristics of LSM and the utilisation of studio-based practices in higher education are studied by conducting literature reviews. Second, the internal and external boundary crossing activities are studied by performing case studies, where the new knowledge creation and establishment of learning networks are in focus. Empirical data has been collected by conducting web-based surveys, theme-based student and student team interviews, direct observation, and participative observation. The outcome of this dissertation suggests that LSM offers a potential educational model for learning the skills of boundary crossing, resulting in a T-shaped skill base. The results of this dissertation include new findings on how commonly studio-based education is utilised world wide in higher education, how LSM differs from the existing configurations that utilise the studio-based model in higher education, as well as active internal and external boundary crossing among students. This dissertation contributes to the discussion of university-society collaboration by the new learning configurations, and to the interdisciplinary education of knowledge workers. The results of this dissertation can be utilised in the development of studio-based configurations in higher education. / Tiivistelmä Tiedonvälittämisen nopeus, epävarmuus ja monimutkaisuus lisääntyvät tietotyöläisten työssä. Lisäksi yleismaailmallisten ja monimutkaisten ongelmien ratkaisemisen vaatima monialainen yhteistyö, sekä yhdessä oppiminen edellyttävät taitoja erilaisten rajojen ylittämiseen. Nämä vaatimukset asettavat uusia haasteita tietotyöläisten korkeakoulutukselle. Metataidot, kuten vuorovaikutustaidot, verkostojen avulla oppiminen ja kriittinen ajattelu, ovat tulleet yhtä tärkeiksi kuin alakohtaiset taidot. Metataidot yhdistettyinä alakohtaisiin taitoihin muodostavat niin kutsutut T-malliset taidot. T-mallisia taitoja omaavat ammattilaiset ovat altistuneet muiden alojen ammattilaisten kokemuksille ja tietotaidolle, ja siten omaavat taitoja rajojen ylittämiseen monialaisissa työryhmissä. Tämä väitöskirja pyrkii vastaamaan kuinka suomalaisessa korkeakoulussa kehitetty, studiomallinen ja monialainen tietotyöläisten koulutusmalli, LAB-malli, vastaa rajojen ylittämisen taitojen kouluttamisen haasteeseen. Tutkimus toteuttaa laadullista tutkimusstrategiaa käyttäen eksploratiivista ja kehittämistutkimuksen lähestymistapaa tutkimusprosessissaan. Alkuperäiset julkaisut keskittyvät studiomallin hyödyntämisen yleisyyteen korkeakoulutuksessa maailmanlaajuisesti, LAB-mallin ominaisuuksiin studiomallina ja opiskelijoiden rajojen ylittämiseen monialaisen koulutuksen aikana. Ensimmäinen julkaisu keskittyy LAB-mallin ominaisuuksien analyysiin ja toinen studiomallin hyödyntämisen selvittämiseen kirjallisuuskatsauksien avulla. Kolmas julkaisu keskittyy rajojen ylittämiseen koulutuksen sisällä uuden tiedon tuottamisen teorian kautta ja neljäs koulutuksen ulkopuolisten rajojen ylittämiseen oppimisverkostojen muodostamisen kautta. Tutkimus tehtiin keräämällä tietoa kyselyillä, teemapohjaisilla opiskelija- ja tiimihaastatteluilla, sekä suoralla, että osallistuvalla tarkkailemisella. Tämä väitöskirja osoittaa, että LAB-malli tarjoaa koulutusmallin rajojen ylittämisen oppimiseen ja siten T-mallisten taitojen oppimiseen. Tulokset osoittavat, että studiomallin hyödyntäminen on lisääntynyt korkeakoulutuksessa, LAB-malli on omaleimainen verrattuna muihin studiomallia noudattaviin korkeakoulutuksiin ja että koulutuksen aikana opiskelijat ylittävät rajoja aktiivisesti. Tämä väitöskirja osallistuu keskusteluun korkeakoulujen yhteiskunnallisesta yhteistyöstä, sekä monialaisen ja studiomallisen oppimisen mahdollisuuksista tietotyöläisten kouluttamisessa. Tämän väitöskirjan tuloksia voidaan hyödyntää edelleen kehitettäessä studiomallisia korkeakoulujen oppimisympäristöjä.
363

Etude des patrons de recombinaison, de leur déterminisme génétique et de leurs impacts en sélection génomique / Study of the recombination patterns, of their genetic determinisms and of their impact on genomic selection in the ovine French breed Lacaune

Petit, Morgane 17 October 2017 (has links)
La recombinaison génétique est un processus biologique fondamental, ayant lieu au cours de la méiose et assurant la bonne ségrégation des chromosomes, ainsi que le maintien de la variabilité génétique grâce au brassage intrachromosomique. La recombinaison a été étudiée dans de nombreuses espèces, en particulier chez les Mammifères et les animaux d’élevage, comme les bovins, les porcs ou les ovins. Dans tous les cas, une variation du taux de recombinaison a été observée entre les individus et il a été démontré qu’elle était héritable et sous déterminisme génétique. Dans certaines espèces, des cartes génétiques ont également été construites, ce qui a permis de localiser les crossingovers et de détecter de très petites zones du génome où la recombinaison était importante : les points chauds. En race ovine Lacaune, de nombreuses données de génotypages sont disponibles, notamment grâce à l’existence de deux puces : une de moyenne densité avec 54 000 marqueurs et une de haute densité avec 600 000 marqueurs. Deux jeux de données étaient donc disponibles ; un jeu de données familial avec près de 6 000 individus apparentés et génotypés pour les 54 000 marqueurs et un jeu de données comportant 70 Lacaune non apparentés et génotypés pour les 600 000 marqueurs. Des cartes génétiques ont donc été créées pour ces deux jeux de données. Avec les animaux non apparentés, environ 50 000 points chauds ont été détectés. Le jeu de données familial a permis d’observer des motifs de distribution de la recombinaison communs aux autres Mammifères. Enfin, la combinaison des deux jeux de données a révélé la présence de signatures de sélection et a permis de créer une carte génétique de haute densité. De plus, une variation du taux de recombinaison a été observée entre les individus et a pu être liée à l’existence de 2 QTLs majeurs sur les chromosomes 6 et 7. Des gènes candidats plus ou moins bien connus ont pu être proposés, voire étudiés : RNF212 et HEI10. De plus, une comparaison avec une autre population ovine a permis de montrer que les cartes de recombinaison étaient quasiment identiques, mais que le taux de recombinaison individuel était soumis à un déterminisme génétique différent. Il a également été possible de proposer une application concrète pour l’utilisation des cartes génétiques en sélection génomique, grâce à la création de puces basse densité pouvant être utilisées pour l’imputation des reproducteurs et donc favoriser le génotypage et la sélection génomique à moindre coût. / Genetic recombination is a fundamental biological process, which occurs during the meiosis. It allows the good segregation of the chromosomes and contributes to maintain the genetic diversity. Recombination was already studied in a lot of different species, especially in mammals and in farm animals, such as the pig, the cattle or the sheep. In each case, a variation of the recombination rate between the individuals was observed. This variation was heritable and under genetic determinism. In some species, genetic recombination maps were also created, which allowed to localize the crossovers and to detect really tiny genomic regions where the recombination is huge: the recombination hotspots. In the Lacaune breed sheep, a lot of genotyping data are available thanks to two existing arrays: a first with a medium density of markers (about 54,000 markers) and a second with a high density of markers (about 600,000 markers). Two datasets were thus available: a familial dataset with about 6,000 animals genotyped for the 54,000 markers and a dataset of 70 unrelated Lacaune genotyped for the 600,000 markers. Genetic recombination maps were created for these two datasets. With the 70 unrelated Lacaune, about 50,000 hotspots were detected. The familial dataset allowed to observe the mammals common recombination patterns. Finally, when the two datasets were combined, selection signatures were revealed and a high density recombination map were created. Furthermore, a variation of the recombination rate within the individuals was observed and was associated to 2 main QTLs on the chromosomes 6 and 7. Already known, or not, candidate genes were proposed and sometimes studied: especially RNF212 and HEI10. Finally, a comparison with another sheep breed revealed that the genetic recombination maps were really similar, but the individual recombination rate was under a different genetic determinism. A concrete application of the genetic recombination map in genomic selection was also proposed thanks to the creation of lowdensity SNPs sets, which could be used to impute the animals and thus to improve the genotyping and the genomic selection for lessercosts.
364

Feasibility of Using Electrical Network Frequency Fluctuations to Perform Forensic Digital Audio Authentication

El Gemayel, Tarek January 2013 (has links)
Extracting the Electric Network Frequency (ENF) fluctuations from an audio recording and comparing it to a reference database is a new technology intended to perform forensic digital audio authentication. The objective of this thesis is to implement and design a range of programs and algorithms for capturing and extracting ENF signals. The developed C-program combined with a probe can be used to build the reference database. Our implementation of the Short-Time Fourier Transform method is intended for the ENF extraction of longer signals while our novel proposed use of the Autoregressive parametric method and our implementation of the zero-crossing approach tackle the case of shorter recordings. A Graphical User Interface (GUI) was developed to facilitate the process of extracting the ENF fluctuations. The whole process is tested and evaluated for various scenarios ranging from long to short recordings.
365

L'influence climatique et anthropique sur trois cours d'eaux bourguignons : géoarchéologie de sites de franchissement sur la Loire, la Saône et le Doubs au cours de l'Holocène / Climatic and anthropogenic influences on three burgundian watercourses : geoarchaelogy of crossing sites on Loire, Saône and Doubs during the Holocene

Steinmann, Ronan 02 July 2015 (has links)
Dans le but de mieux comprendre les facteurs agissant sur le milieu fluvial à l’échelle plurimillénaire, ainsi que les effets de la dynamique alluviale sur la préservation de l’information archéologique, une étude géoarchéologique a été menée sur quatre fenêtres des vallées de la Loire, de la Saône et du Doubs en Bourgogne (France). À partir de sites de franchissement romains et d’un pont médiéval, retrouvés dans le chenal actuel, puis en étendant les recherches à d’autres secteurs, l’évolution des lits mineur et majeur au cours de l’Holocène a été reconstituée. Des informations de natures diverses, datées et spatialisées, ont été croisées : pour les deux derniers siècles, principalement les plans et vues aériennes contemporains, tandis que les périodes plus anciennes sont abordées grâce aux indices archéologiques, à l’analyse géomorphologique du lit majeur et, principalement, aux archives sédimentaires. Ces dernières ont été analysées du point de vue de la sédimentologie de faciès afin d’identifier les processus à l’origine des dépôts. Les grandes étapes de l’évolution des trois grands cours d’eau étudiés, une fois identifiées et datées, ont été confrontées aux données existantes afin d’interroger l’influence qu’ont pu avoir les fluctuations climatiques et les activités humaines sur la dynamique alluviale. La reconstitution de l’évolution du milieu au cours de l’Holocène permet enfin d’aborder la question de la conservation des données archéologiques en domaine alluvial, propice à l’implantation humaine, mais où l’information est la plupart du temps masquée par une succession de processus taphonomiques. / A geoarchaeological study was led on four sections of the valleys of the Loire, Saône and Doubs rivers (Burgundy, France) in order to point out the factors influencing the alluvial dynamics on a multimillennial scale, and their effects on the preservation of archaeological information. Investigations started by roman and medieval remains of bridges discovered in active channels, were then carried out on larger parts of alluvial plains, and altogether allowed the evolutions of the channels during the Holocene period to be deducted. Various types of information on alluvial characteristics were crossed through time and space: ancient maps and XXth century or aerial photographs for centennial scale, archaeological data, geomorphological analysis, but mostly alluvial deposits for older periods. Facies analyses on fluvial sediments led to the identification and the reconstitution of successive sedimentary environments through time. The main steps of the evolution of the three rivers, after being identified and dated, were compared to previous studies in order to estimate the respective roles of climatic changes and anthropic influence on alluvial dynamics, on this regional scale, during the Holocene. Preservation of archaeological information in fluvial deposits is therefore discussed here, to reach a better understanding of taphonomic issues in such environmennts, which are potentially rich in archaeological remains.
366

Effects of a dialogical argumentation instructional model on grade 10 learners’ conceptions of lightning

Hlazo, Noluthando January 2014 (has links)
Magister Educationis - MEd / The study employed a quasi-experimental design to determine the effect of DAIM on learners’ conceptions of lightning. The experimental group was taught using DAIM while the control group was taught the same content using TLM. Data was collected using the Science Attitude Questionnaire (SAQ), Beliefs about Lightning Questionnaire (BALQ), Conceptions of Lightning Questionnaire (COLQ) and Science Achievement Test on Lightning (SATOL) which was used to determine learners’ overall performance on the topic of electrostatics. The data was analysed using both qualitative and quantitative methods. The findings of the study revealed that prior to the intervention (DAIM); the two groups of learners had both the scientific and the indigenous knowledge about lightning. A majority of the learners believed that lightning is caused by witches and traditional doctors. After being exposed to the DAIM most of the learners in the experimental group were found to have changed to the more scientific explanation of cause of lightning and protective measures against lightning. Few learners in the control were classified as possessing an equipollent worldview in terms of the CAT after the post tests. Some learners’ conceptions about lightning wavered between the scientific and traditional worldviews. The Science Attitude Questionnaire showed that both groups of learners had a positive attitude towards science. The findings also suggested that the inclusion of indigenous knowledge in science lessons promoted active participation from the learners, reinforced the learning of science because it promoted conceptual development and scientific literacy. The learners in the study also supported the integration of the scientific and the traditional worldviews about lightning. After the instruction, the learners in both groups seemed to still hold indigenous beliefs in relation to lightning. The post-test results showed that the DAIM group seemed to have been able to link the concept of lightning with electrostatics when they related lightning storms to electric discharge. The experimental group was found to be more elaborate in their explanations of the scientific nature of lightning than the control group which was not exposed to DAIM
367

Rozdíly v chování řidiče při jízdě přes přechod pro chodce v noci a ve dne / Differences in the Driver's Behavior when Driving through a Pedestrian Crossing at Night and in the Daytime

Vlasák, Jaroslav January 2017 (has links)
The theoretical part of the diploma thesis focuses on the drivers reacting on a pedestrian crossing during the day and the night. A particular attention is paid to all the factors that can influence drivers' behaviour while driving through a pedestrian crossing. The influence of the behaviour by these factors often causes car accidents with pedestrians. One of the basic techniques is to analyze the behavior of the driver in the optical perception of stimuli that affect the optical response. Eyetracker is used to measure the optical responses. This device monitors changes of the angle of a driver's view, navigation of a driver and the driver's reaction on different stimuli while driving. The practical part of the thesis deals with an analysis of the drivers' behaviour while driving through a pedestrian crossing during the day and during the night. Twelve drivers took part in the day measurement of driving through the pedestrian crossing in Brno. Night measurement was taken place in Břeclav and Lednice with the attendance of seven drivers. During the ride are monitored the optical reactions of drivers on various impulses with the use of a special device Eyetracker.
368

Konverze Heršpické ulice na sběrnou komunikaci / Conversion of Heršpická street to urban road

Mareček, Zdeněk January 2018 (has links)
The aim of this project is a refurbishment of the local collecting road Herspicka located in Brno, Czech republic. The goal of the project is to improve the accessibility for various transport means. The project contains design of several crossroads situated along this major road. This thesis is elaborated in a form of a technical study. The traffic flows intensity calculation was conducted on studied level crossings along the studied road.
369

Kolmá křížení tramvajových tratí s vlečkami / Perpendicular crossings tram tracks with railway sidings

Omaník, David January 2018 (has links)
The diploma thesis deals with the perpendicular crossing of tram track with railway siding. The structure of crossing is described both in the Czech Republic and in the world. The aim of the thesis is to find the recommended design solution for the crossing of tram and railway tracks with regard to legislation and feasibility. After a comparison of the existing structures is chosen which satisfies the conditions of feasibility.
370

Rekonstrukce železniční stanice Lipová Lázně / Upgrading of Lipová Lázně Railway Station

Kopecká, Denisa January 2018 (has links)
The master's thesis deals with reconstruction design of Lipová Lazně railway station. The main goal is to design new platforms suitable for passengers with reduced mobility and orientation and valid standart. Another goal is to increase line speed. Part of the thesis includes modifications of railway superstructure, substructure and drainage system of the station.

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