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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.
51

Investigation Of The Impact Of Video-based Anchored Instruction On The Implementation Of Inclusive Practices By Students With Learning Disabilities

O'Brien, Christopher 01 January 2006 (has links)
For several years emerging trends in special education services have favored inclusion for students with disabilities. Concurrent to this evolution of philosophy in special education has been the advent of what could be considered inclusive instructional practices--those methods that aid in the successful inclusion of students with disabilities. These inclusive practices include co-teaching, cooperative learning, peer-mediated instruction, positive behavioral support, embedded learning strategies, and content-enhancements (Ehren, Lenz, & Deshler, 2005; King-Sears, 1997). As inclusive placements become an increasingly common standard of practice, particularly for students with learning disabilities, the need to assist general educators in establishing inclusive classrooms becomes a major priority. It is logical then to prioritize the propagation of inclusive practices in general education classrooms--practices that would take into account the natural diversity of student populations likely to be present in American classrooms. Cooperative learning, in the form of Literature Circles, is offered in this study as a highly effective method for laying the groundwork for inclusion. This study, rooted in the theory of anchored instruction, attempted to address the need for incorporating inclusive practices by investigating the potential for students with learning disabilities to implement Literature Circles by viewing video models. This research evaluated the impact of video models on three levels--the extent to which the video models improve the ability for students with learning disabilities to a) learn the foundational information and rationale of a strategy, b) implement the strategy effectively, and c) improve academic outcomes by implementing the strategy. Finally, an attempt was made to further probe student perception of learning a strategy from a video model through focus group interviews. Data was collected using a quasi-experimental design. Forty-nine classrooms were randomly assigned to video-based and traditional treatments. Students attempted to implement Literature Circles in their middle school social studies classes. Following data collection, quantitative statistical analysis was completed using Multivariate Analysis of Variance (MANOVA) to examine group differences in knowledge of the essential elements of the strategy, implementation of the strategy, and content achievement. Qualitative analysis of student focus group responses was completed by scrutinizing transcripts for general themes (Erickson, 1986). This study made a connection between lines of research on video-based anchored instruction for students with learning disabilities and video-anchors in teacher preparation. The full sample of 196 students, including 43 students with learning disabilities, demonstrated significantly more effective implementation of Literature Circles. Students in the video model focus group indicated that they benefited from the explicit, positive peer models demonstrated in the video. The continued proliferation of visual images in the form of video-based models represents a positive step toward increasing available resources to students and teachers and ultimately improving outcomes for students with learning disabilities.
52

Comparing the Effects of Student-Created Content Acquisition Podcasts and Teacher-Created Content Acquisition Podcasts

Jordan, Katlyn 26 July 2022 (has links)
No description available.
53

Cysteine residues of the mammalian GET receptor: Essential for tail-anchored protein insertion?

Schaefer, Moritz 30 May 2017 (has links)
No description available.
54

Evolution and Classification of the Cariceae-Dulichieae-Scirpeae Clade (Cyperaceae)

Léveillé-Bourret, Étienne 07 May 2018 (has links)
For over a century, the origins and mechanisms underlying the diversification of the enormous cosmopolitan genus Carex (>2,100 species; Cariceae, Cyperaceae or sedge family) have remained largely speculative. Although its unique morphology (e.g., unisexual flowers, perigynia) clearly indicated it was a natural group, it obscured its relationships to all other Cyperaceae because the morphological gap between it and the rest of the family was so wide. Consequently, no plausible sister group to Carex has ever been proposed. Early molecular analyses narrowed the problem by placing Carex within a strongly-supported clade with the enigmatic monospecific genus Khaosokia, and tribes Dulichieae and Scirpeae (hereafter CDS), a group consisting of 2,250 species, or approximately 41% of all Cyperaceae. However, poor taxonomic sampling and the limited number of molecular markers used in these studies meant that the sister group to Carex remained a mystery. The goals of this thesis were to resolve evolutionary relationships within the CDS clade, to identify the sister group to Carex, and to develop a new natural tribal classification of CDS that could be used in future biogeographic and comparative analyses of Carex and its relatives. Initial phylogenetic analyses using two plastid markers (matK, ndhF) identified seven major CDS lineages, and suggested that Carex could be nested within a paraphyletic Scirpeae. However, backbone support for these relationships was low due to an ancient rapid radiation (~10 million years) followed by long divergence of the seven major lineages (~40 million years). The addition of conventional sequence-based markers from the plastid genome (rps16) and nuclear ribosomal region (ETS-1f, ITS) indicated that a traditional molecular approach would not resolve these key backbone nodes. Consequently, a recently developed flowering-plant-specific anchored enrichment probe kit targeting hundreds of conserved nuclear genes combined with next generation sequencing was used to resolve the CDS backbone. Although the resulting phylogenomic dataset was able to resolve the CDS backbone with high support, the topology and branch lengths only reaffirmed the isolated position of Carex. However, comparative morphological analyses of specimens at key herbaria not only suggested that Sumatroscirpus, a rare genus thought to be endemic to Sumatra, could be sister to Carex, but they also provided an easily accessible site to collect DNA in Northern Vietnam. Subsequent phylogenetic analyses of plastid (matK, ndhF, rps16) and nuclear ribosomal (ETS-1f, ITS) markers strongly supported Sumatroscirpus as the sister to Carex, and molecular dating estimates suggested they shared a common ancestor in the late Eocene (~36 million years ago). Comparative studies and ancestral state estimates of key morphological characters were congruent with this hypothesis, suggesting that the perigynium is not unique to Carex, but in fact a synapomorphy shared with Sumatroscirpus. This means that the initial key innovation in the remarkable diversification of Carex is not the perigynium, but could be the release of mechanical constraints that permitted the evolution of the remarkable morphological diversity of Carex perigynia seen today. A taxonomic revision of Sumatroscirpus revealed that this purportedly monospecific genus actually consisted of four species, and it extended its range over 2,400 km to the north into Northern Vietnam, Myanmar, and Southwestern China. The phylogenetic framework provided by the previous studies enabled a new tribal and generic classification of CDS to be proposed. Seven monophyletic tribes are recognised including four new tribes (Calliscirpeae, Khaosokieae, Sumatroscirpeae, Trichophoreae), and a new genus (Rhodoscirpus). Morphological synapomorphies are identified for all recognized tribes, and a worldwide treatment, including identification keys, is provided for Sumatroscirpus species, CDS genera, and Cyperaceae tribes.
55

Molecular Studies of South American Teiid Lizards (Teiidae: Squamata) from Deep Time to Shallow Divergences

Tucker, Derek B. 01 June 2016 (has links)
I focus on phylogenetic relationships of teiid lizards beginning with generic and species relationship within the family, followed by a detailed biogeographical examination of the Caribbean genus Pholidoscelis, and end by studying species boundaries and phylogeographic patterns of the widespread Giant Ameiva Ameiva ameiva. Genomic data (488,656 bp of aligned nuclear DNA) recovered a well-supported phylogeny for Teiidae, showing monophyly for 18 genera including those recently described using morphology and smaller molecular datasets. All three methods of phylogenetic estimation (two species tree, one concatenation) recovered identical topologies except for some relationships within the subfamily Tupinambinae (i.e. position of Salvator and Dracaena) and species relationships within Pholidoscelis, but these were unsupported in all analyses. Phylogenetic reconstruction focused on Caribbean Pholidoscelis recovered novel relationships not reported in previous studies that were based on significantly smaller datasets. Using fossil data, I improve upon divergence time estimates and hypotheses for the biogeographic history of the genus. It is proposed that Pholidoscelis colonized the Caribbean islands through the Lesser Antilles based on biogeographic analysis, the directionality of ocean currents, and evidence that most Caribbean taxa originally colonized from South America. Genetic relationships among populations within the Ameiva ameiva species complex have been poorly understood as a result of its continental-scale distribution and an absence of molecular data for the group. Mitochondrial ND2 data for 357 samples from 233 localities show that A. ameiva may consist of up to six species, with pairwise genetic distances among these six groups ranging from 4.7–12.8%. An examination of morphological characters supports the molecular findings with prediction accuracy of the six clades reaching 72.5% using the seven most diagnostic predictors.
56

Evolutionary Studies of Fruit-Piercing Moths in the Genus Eudocima Billberg (Lepidoptera: Erebidae)

Crystal Klem (7053191) 16 October 2019 (has links)
<p>The prevalence of monoculture and landscape simplification is correlated with diminished biodiversity and increased presence of harmful pest species in crop environments. Lepidoptera is the largest clade of herbivorous insects, with many agriculturally significant species. The pest status of insects in agricultural settings is human-defined based on behaviors that may negatively impact the yield of susceptible crops. As such, both the insect behavior and the affected crop play a part in determining pest status. One helpful means of understanding pest status involves using pest injury guilds, which distinguish different pest groups based on similar kinds of injury to comparable plant tissues. Pest injury guilds defined in the literature are reviewed and then applied to agriculturally-significant Lepidoptera. Specialized Lepidoptera behaviors are reviewed within their respective injury guilds, and the systematics, ecology, and control options for fruit-piercing moths are discussed within the context of pest Lepidoptera behaviors. To address the need for distribution information for economically relevant Lepidoptera, the first annotated checklist of pest Lepidoptera is also provided for the United States and Canada. This checklist includes 80 agriculturally significant Lepidoptera species and complexes, and incorporates notes on distribution, species delimitation, natural history, and establishment.<br></p> <p><b> </b></p> <p>Fruit-piercing moths in the genus <i>Eudocima</i> Billberg, 1820 have significant pest status as adults rather than as larvae, and directly injure fruits using a specially-adapted proboscis. There are at least 48 <i>Eudocima</i> species which are found in the world’s tropics, but confusion persists in the classification of this genus and there are several suspected complexes. Additionally, the area of origin for this group is uncertain, although the Oriental region has been postulated. A comprehensive phylogenetic analysis of <i>Eudocima</i> is conducted using 82 morphological characters, which are each described and figured, and analyzed using parsimony. Results suggest that <i>Eudocima</i> is not monophyletic. Strongly-resolved relationships were recovered, although these did not correspond with previous generic concepts. The Australian region is recovered as the most parsimonious area of origin for <i>Eudocima</i>, and patterns of dispersal, particularly between the Oriental and Australian regions along the Indo-Australian Archipelago, are discussed.</p> <p> </p> <p>The <i>Eudocima phalonia</i>-complex is distributed throughout the Old World and has been the subject of increasing interest and research due to its economic impact in the tropics and status as a potential invasive species. The recent description of closely-related sister species, as well as morphological variation documented within <i>E. phalonia</i> itself, suggests possible speciation occurring within <i>E. phalonia</i> populations across its wide geographic range. To test species boundaries for this taxon, a molecular phylogeny is constructed using anchored hybrid enrichment and a next-generation sequencing approach. Sampling for this phylogeny was informed using a global range map for <i>E. phalonia</i>, which was developed using georeferenced specimen data from natural history collections. Biogeographic analyses are also conducted to investigate the area of origin and dispersal patterns of <i>E. phalonia</i>, and to examine possible speciation modes and gene flow. Georeferenced range information is also utilized along with environmental variables in constructing a correlative environmental niche model using MaxEnt, which is used to evaluate a previous mini risk assessment for environmental suitability in the continental United States for <i>E. phalonia</i> establishment. Results suggest that <i>E. phalonia</i> is monophyletic, with gene flow still occurring between populations. The area of origin for <i>E. phalonia</i> is postulated to be the Oriental region, although further investigation is needed. Range predictions for <i>E. phalonia</i> from environmental modelling were performed for both the Old World, which concurred well with occurrence data, and for the New World. Assessment of environmental suitability for <i>E. phalonia</i> in the continental United States suggests areas in Florida and along the Gulf Coast are most favorable for establishment.</p>
57

La morphodynamique éolienne en régions sèches : des échelles spatiales et temporelles aux outils / Aeolian morphodynamics in drylands : spatial and temporal scales, associated tools

Venard, Cédric 13 December 2012 (has links)
Les régions sèches situées à la périphérie des déserts sont généralement peuplées et mises en valeur sur un mode sédentaire. Elles partagent cependant avec les milieux désertiques des conditions environnementales qui les rendent sensibles et fragiles. Cela implique de bien connaître les mécanismes de leurs milieux, a fortiori dans un contexte de désertification qui augmente le risque environnemental. Celui-ci est souvent évalué par le suivi de la végétation, mais l’expérience de terrain montre que les formes éoliennes pourraient apporter des compléments utiles. La morphodynamique éolienne joue en effet un rôle non négligeable dans le risque environnemental en régions sèches. Si, dans les systèmes désertiques, l’influence des activités humaines sur l’évolution des formes éoliennes de grande taille est réduite, dans les régions sèches non-désertiques, elles sont de plus petite dimension et leur vitesse de réaction aux changements des conditions du milieu est élevée. Elles sont de surcroît liées aux autres composants du paysage, avec lesquels elles interagissent fortement, et leur fonctionnement peut être corrélé aux modalités d’exploitation du milieu. Cela en fait des indicateurs pertinents et leur suivi doit donc être conçu dans une approche systémique appuyée sur une bonne maîtrise des fondements physiques de l’étude de la morphodynamique éolienne qui sont présentés en ouverture de ce mémoire. Différents outils et concepts élaborés dans les contextes désertiques, parmi lesquels les déplacements potentiels sableux et la densité d’obstacle, sont détaillés. Les effets paysagers de la morphodynamique éolienne sont illustrés par divers exemples. Son intégration dans les études de suivi est alors questionnée pour démontrer que de nouvelles approches peuvent être explorées. Les propositions faites s’intéressent en particulier à un objet, la forme éolienne d’obstacle, qui reste mal connu malgré la place qu’il tient dans les paysages des régions sèches. Une grille de caractérisation fine de cet objet est définie, à partir de laquelle un protocole de quantification et d’évaluation qualitative nécessaire à la production d’indicateurs peut être élaboré. Pour cela, les méthodes développées doivent être reproductibles et minimiser la complexité et les coûts de mise en oeuvre. Dans le domaine de la télédétection, la facilité d’utilisation et la précision des images du Pixy, paramoteur léger à voile souple, démontrent le potentiel des vecteurs de type drone. L’intérêt des satellites à très haute résolution spatiale pour, notamment, la généralisation d’études ciblées est également démontré. Les images produites correspondent notamment à une échelle intermédiaire qui faisait jusqu’alors défaut. Parmi les fournisseurs d’images très haute résolution spatiale, Google Earth est une alternative possible des fournisseurs commerciaux. La disponibilité de plus en plus grande d’images de résolution très élevée offre des perspectives d’applications dans des domaines variés. Leur exploitation présente cependant des contraintes que la Morphologie Mathématique (MM), discipline de l’analyse d’image orientée-objet, permet de contourner. Les outils de la MM facilitent l’analyse façon robuste des images non corrigées, du type Pixy ou Google Earth. Elle s’appuie sur des procédures simples à reproduire, dont les résultats s’expliquent facilement. Elle participe ainsi à réduire le coût des études. Or, la question économique du diagnostic environnemental ne peut être évacuée, en particulier dans les pays concernés par la lutte contre la désertification. Chaque chapitre de ce mémoire démontre l’importance de la prise en considération de deux seuils : d’une part, le seuil d’hétérogénéité, en-deçà duquel l’information recherchée est noyée dans le bruit d’un trop grand détail, d’autre part, le seuil d’homogénéité, au-delà duquel la maille d’analyse fait que l’information est trop lissée pour être pertinente.... / Drylands share with deserts many environmental conditions that make them sensitive and fragile. It is a necessity to understand the mechanisms of these environments, especially in contexts where there is a risk of desertification. Such an understanding is often assessed by monitoring vegetation. Field experience, however, shows that aeolian morphodynamics may provide useful additional information. The aeolian morphodynamics plays indeed a significant role in the environmental risk of drylands. In desert systems, the anthropogenic pressure on aeolian processes is low. On the other hand, in non-desert drylands, features are smaller but have a faster reaction time to environmental change. They interact strongly with other components of the landscape, such as human activities. Accordingly, the study of non-desertic aeolian morphodynamics has to be designed following a systematic approach. It relies on a good knowledge of fundamental physics of wind geomorphology that is described in this dissertation. Various tools and concepts developed in desert environments, including potential displacement and roughness density, are given. The effects of aeolian morphodynamics on landscapes are illustrated by various examples. Standard studies of wind dynamics are discussed and questioned to demonstrate that new approaches can be explored. This study focuses anchored dunes, which remain poorly studied despite their importance in drylands. Anchored dunes are described and characterized in detail. Then a protocole of quantification and qualitative evaluation can be elaborated.Our aim was to develop methods that are reproducible and minimize the complexity and costs of implementation. The unmanned platform, Pixy, illustrates the potential of drones which provide accurate images with a great flexibility of use. The interest of very high spatial resolution imagery provided by satellites such as QuickBird is also demonstrated. Their images introduce to an intermediate scale between field and large-scale satellite imagery. Among the providers of very high spatial resolution imagery, Google Earth (GE) appears to be a good alternative to commercial suppliers. Increasing availability of free high resolution images offers potential applications in various fields. However, their use has constraints that are managed by Mathematical Morphology (MM), an object-oriented image analysis discipline. Tools from MM allow the analysis of uncorrected images, like those of Pixy or GE. It relies on simple procedures easy to reproduce and explain. It thus contributes to reducing the cost of studies. This economic issue of environmental diagnosis cannot be ignored, especially in the countries concerned by the fight against desertification.Each chapter of this thesis demonstrates the importance of two thresholds through particular example. The threshold of heterogeneity, below which information is embedded in the background noise produced by too much detail, is the first one. The threshold of homogeneity, beyond which information is too smooth to be relevant, is the second one. This work attempts to show how these thresholds may have direct effects on results of a remote sensing study. This consideration is thus a structuring element of the methods used. Beyond the issue of aeolian morphodynamics, this thesis combines semi-automatic characterization methods of landscape elements with processes of multi-scalar integration. The results are potentially useful to any approach that seeks to understand the effects of a phenomenon at different scales.
58

Gestión de riesgos en la ejecución de muros anclados

Aponte Cervantes, Manuel Raúl, Sulca Torres, Marco Jesús January 2015 (has links)
La presente investigación tuvo como objetivo principal elaborar una propuesta de plan de gestión de riesgos aplicable para la ejecución de muros anclados en proyectos de edificaciones en la ciudad de Lima. La investigación es de tipo descriptivo, correlacional y explicativo; el diseño es transversal ya que la información recopilada es de proyectos ejecutados en el periodo de 2012 al 2015. La metodología que se utilizó fue recolección de información por medio de entrevistas sobre los riesgos que más se presentan en la ejecución de muros anclados y sus impactos, un análisis de la información bajo los conocimientos propuestos por el PMBOK y la elaboración de una propuesta de plan de gestión de riesgos aplicable para éste tipo de proyectos. La investigación concluye que al aplicar el plan de gestión propuesto se puede optimizar los resultados de plazos y costos en la ejecución de muros anclados en proyectos de edificaciones. This research has as main objective to develop a proposed "Risk management plan" applies to the execution of walls anchored in building projects in the city of Lima. The research is descriptive, correlational and explanatory type; the design is transversal because information is collected projects in the period 2012 to 2015. The methodology used was gathering information through interviews about the risks that are presented more in the execution of anchored walls and its impacts, an analysis of the information under the knowledge proposed by the PMBOK and the development of a proposed “Risk management plan" applicable to this type of project. The research concludes that by applying the proposed management plan can optimize the results of time and cost in implementing projects anchored walls of buildings.
59

Regions, distances and graphs

Collette, Sébastien 22 November 2006 (has links)
We present new approaches to define and analyze geometric graphs. <p><p>The region-counting distances, introduced by Demaine, Iacono and Langerman, associate to any pair of points (p,q) the number of items of a dataset S contained in a region R(p,q) surrounding (p,q). We define region-counting disks and circles, and study the complexity of these objects. Algorithms to compute epsilon-approximations of region-counting distances and approximations of region-counting circles are presented.<p><p>We propose a definition of the locality for properties of geometric graphs. We measure the local density of graphs using the region-counting distances between pairs of vertices, and we use this density to define local properties of classes of graphs.<p>We illustrate the locality by introducing the local diameter of geometric graphs: we define it as the upper bound on the size of the shortest path between any pair of vertices, expressed as a function of the density of the graph around those vertices. We determine the local diameter of several well-studied graphs such as the Theta-graph, the Ordered Theta-graph and the Skip List Spanner. We also show that various operations, such as path and point queries using geometric graphs as data structures, have complexities which can be expressed as local properties.<p><p>A family of proximity graphs, called Empty Region Graphs (ERG) is presented. The vertices of an ERG are points in the plane, and two points are connected if their neighborhood, defined by a region, does not contain any other point. The region defining the neighborhood of two points is a parameter of the graph. This family of graphs includes several known proximity graphs such as Nearest Neighbor Graphs, Beta-Skeletons or Theta-Graphs. We concentrate on ERGs that are invariant under translations, rotations and uniform scaling of the vertices. We give conditions on the region defining an ERG to ensure a number of properties that might be desirable in applications, such as planarity, connectivity, triangle-freeness, cycle-freeness, bipartiteness and bounded degree. These conditions take the form of what we call tight regions: maximal or minimal regions that a region must contain or be contained in to make the graph satisfy a given property. We show that every monotone property has at least one corresponding tight region; we discuss possibilities and limitations of this general model for constructing a graph from a point set.<p><p>We introduce and analyze sigma-local graphs, based on a definition of locality by Erickson, to illustrate efficient construction algorithm on a subclass of ERGs. / Doctorat en sciences, Spécialisation Informatique / info:eu-repo/semantics/nonPublished
60

Obloukový most přes dálnici / Arch bridge over a highway

Pěkník, Robin January 2015 (has links)
The subject of this master's thesis is design of road bridge over highway D1 by the city Přerov. From the three proposed solutions has been chosen bridge with self-anchored arched structure which is good for deep notch. The concrete bridge was designed and assessed according to current Eurocodes. The thesis includes detailed structural analysis, drawings and visualization of the bridge. The analysis was performed using software Scia Engineer including time dependent analysis (TDA). Assessment of structure was made in Excel or by hand.

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