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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.
121

Aspects of the molecular evolution of baculoviruses and flaviviruses

Zanotto, Paolo Marinho de Andrade January 1995 (has links)
No description available.
122

A hierarchical genetic analysis of swan relationships

Harvey, Nicholas G. January 1999 (has links)
No description available.
123

A phylogeny of Begoniaceae Bercht. and J. Presl

Forrest, Laura Lowe January 2000 (has links)
No description available.
124

Taxonomy of some Australian serolid and sphaeromatid isopods (Crustacea)

Harrison, Keith January 1982 (has links)
The taxonomy of marine isopod crustaceans belonging to the families Serolidae and Sphaeromatidae is considered. All known Australian serolids are discussed and a new species is described from Victoria. The Serolis minuta-group (sensu Monod, 1971) is shown to exhibit great morphological variation and the differentiation of distinct species within this group is not currently possible. The differences between the minuta-group and other Australian species are described and a key to all known serolids from Australia is provided. All known sphaeromatids from the Queensland coast of Australia are redescribed, and 8 genera and 25 species new to science are described from this region. A further 1 new genus and 3 new species of Sphaeromatidae are described from southern and western Australian coasts. The morphology of ovigerous female sphaeromatids is reviewed for all known genera world-wide. The expansion of the maxilliped is shown to be directly related to brood pouch form, and some relationship is indicated between brood pouch structure and environment. Twenty different forms of brood pouch are described. For adult male sphaeromatids, an illustrated key to all known genera world-wide is provided and the known geographical distributions of the genera are listed. A preliminary revision at the species level of the entire family Sphaeromatidae is briefly attempted and the need for a natural classification within this family (especially at the generic level) is emphasised, some of the current genera being obviously artificial groups. It is shown that the families Sphaeromatidae and Serolidae are not as closely related phylogenetically as was previously thought, and the opinion is rendered that the genera Ancinus Milne Edwards, Bathycopea Tattersall and Tecticeps Richardson should probably be removed from the Sphaeromatidae.
125

Sedimentology of the Catalina Dome and taxonomy of Mistaken Point small fronds

Mason, Sara 04 November 2013 (has links)
Research carried out in the Ediacaran of eastern Newfoundland focused on two projects: sedimentology of the Conception and St. John’s groups exposed on the Bonavista Peninsula; and taxonomic descriptions of the small, stemmed frondose fossils at Mistaken Point on the Avalon Peninsula. Sedimentological study of the upper Conception and lower St. John's groups at Catalina Dome on Bonavista Peninsula extends our understanding of the Conception Basin, in which the oldest known complex, deep marine organisms lived, by a factor of two. Mudstone-rich turbidites dominate the succession, and a lack of wave-generated structures or other shallow-water indicators support the interpretation that the depositional environment was deep-marine. The basal part of the succession contains seismoturbidites that show no evidence of horizontal translation, implying that deposition occurred on a flat basin plain. Strata higher in the succession exhibit horizontally slumped beds, implying a transition into slope deposition. Turbidite ripple marks show a change in paleocurrent direction from eastward to southward in the Trepassey Formation, consistent with a change from convergent to strike-slip tectonics that occurred diachronously across the basin. Volcanic ash beds are more common in the Catalina Dome succession than on the Avalon Peninsula, reflecting deposition closer to the volcanic source. These volcanic beds are associated with diverse fossil assemblages rich in rangeomorphs that locally persist into the Fermeuse Formation, in contrast with the Avalon Peninsula where the Fermeuse Formation contains only simple discoid fossils. This taphonomic window lends support to the hypothesis that the form genus Aspidella represents the holdfasts of Ediacaran fronds. Stemmed small frond fossils from Mistaken Point, Avalon Peninsula, have often been informally referred to as “featherdusters”, but due to their small size and consequent poor preservation, they have not until now been formally described. The small, stemmed fronds are more diverse than previously realized, and include representatives of taxa described from elsewhere in Newfoundland, juveniles of other Mistaken Point fronds, and two new monospecific genera. This biodiversity suggests that the basal elevated tier that the small fronds occupied was competitive, with convergent evolution of frondose taxa showing distinct architecture and constructions, but broadly similar size and shape. / Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2013-10-30 12:12:23.297
126

A molecular phylogenetic study of the galagos, strepsirrhine primates and archontan mammals

Bayes, Michelle January 1998 (has links)
No description available.
127

The taxonomic name resolution service: an online tool for automated standardization of plant names

Boyle, Brad, Hopkins, Nicole, Lu, Zhenyuan, Raygoza Garay, Juan Antonio, Mozzherin, Dmitry, Rees, Tony, Matasci, Naim, Narro, Martha, Piel, William, Mckay, Sheldon, Lowry, Sonya, Freeland, Chris, Peet, Robert, Enquist, Brian January 2013 (has links)
BACKGROUND:The digitization of biodiversity data is leading to the widespread application of taxon names that are superfluous, ambiguous or incorrect, resulting in mismatched records and inflated species numbers. The ultimate consequences of misspelled names and bad taxonomy are erroneous scientific conclusions and faulty policy decisions. The lack of tools for correcting this 'names problem' has become a fundamental obstacle to integrating disparate data sources and advancing the progress of biodiversity science.RESULTS:The TNRS, or Taxonomic Name Resolution Service, is an online application for automated and user-supervised standardization of plant scientific names. The TNRS builds upon and extends existing open-source applications for name parsing and fuzzy matching. Names are standardized against multiple reference taxonomies, including the Missouri Botanical Garden's Tropicos database. Capable of processing thousands of names in a single operation, the TNRS parses and corrects misspelled names and authorities, standardizes variant spellings, and converts nomenclatural synonyms to accepted names. Family names can be included to increase match accuracy and resolve many types of homonyms. Partial matching of higher taxa combined with extraction of annotations, accession numbers and morphospecies allows the TNRS to standardize taxonomy across a broad range of active and legacy datasets.CONCLUSIONS:We show how the TNRS can resolve many forms of taxonomic semantic heterogeneity, correct spelling errors and eliminate spurious names. As a result, the TNRS can aid the integration of disparate biological datasets. Although the TNRS was developed to aid in standardizing plant names, its underlying algorithms and design can be extended to all organisms and nomenclatural codes. The TNRS is accessible via a web interface at http://tnrs.iplantcollaborative.org/ webcite and as a RESTful web service and application programming interface. Source code is available at https://github.com/iPlantCollaborativeOpenSource/TNRS/ webcite.
128

Réalité augmentée haptique : théorie et applications / Haptics augmented reality : theory and applications

Bayart, Benjamin 07 December 2007 (has links)
Dans cette thèse, nous introduisons le concept de Réalité Augmentée Haptique (RAH) en définissant une taxonomie à deux axes. Le premier dénommé Haptique Augmentée (HA) représente l’ensemble des applications qui modifient/augmentent une donnée haptique existante. Le second axe, appelé Augmentation Haptique (AH), considère les applications qui utilisent la modalité haptique pour fournir une information supplémentaire à l’utilisateur. Par la suite, nous illustrons ces concepts sous forme d’une application de télé-diagnostic, permettant l’exploration d’un objet mixte, composé de parties réelles et virtuelles, ou la comparaison entre un objet réel et un virtuel ; d’un nouvel algorithme pour l’enseignement d’un chemin par guidage haptique, tout en évitant les problèmes de passivité et de dépendance de l’apprenti ; et de l’emploi de ces deux notions dans une application de peinture virtuelle sur un quelconque objet réel (avec croisement d’augmentations visio-haptique), le tout enrichi d’un processus visuel de Réalité Diminuée. / This thesis introduces the concept of Haptics Augmented Reality (HAR) defining a taxonomy of two concepts. The first called Enhanced Haptics (EH) consists in applications that enhance/modify/… an existing haptic data. The second concept, named Haptic Enhancing (HE), considers applications using the haptic channel to provide additional information to the user. Thereafter, these concepts are illustrated as a tele-diagnosis application, enabling the exploration of a mixed object, composed of real and virtual parts, or the comparison between a real object and a virtual one; as a new algorithm of haptic guidance dedicated to path teaching scenarios, avoiding the problems of passivity and dependence of he apprentice; and the use of these two concepts within a application of virtual painting onto any real object, enriched with a visual Diminished Reality process.
129

Revisão taxonômica das espécies neotropicais dos gêneros Trichopoda Berthold, 1827 e Ectophasiopsis Townsend, 1915 (Diptera, Tachinidae, Phasiinae) / Taxonomic revision of the Neotropical species of the genera Trichopoda Berthold, 1827 and Ectophasiopsis Townsend, 1915 (Diptera, Tachinidae, Phasiinae)

Dios, Rodrigo de Vilhena Perez 06 June 2014 (has links)
Trichopoda Berthold, 1827, é um gênero de Tachinidae pertencente à subfamília Phasiinae, originalmente distribuída nas Américas. As espécies de Phasiinae são parasitóides de insetos da ordem Hemiptera, principalmente Heteroptera e possuem grande importância para o controle biológico. O gênero está incluído no grupo “Trichopoda typica” sensu Sabrosky (1950), junto com o gênero Eutrichopoda Townsend, 1908. O gênero Trichopoda inclui várias dezenas de espécies nominais descritas, muitas delas foram sinonimizadas e algumas foram transferidas para outros gêneros. Embora um grupo morfologicamente vistoso e também muito importante do ponto de vista agrícola, não há nenhum trabalho de revisão incluindo suas espécies. Antes do presente estudo eram consideradas válidas 22 espécies Neotropicais em Trichopoda divididas em dois subgêneros. Após o presente estudo são consideradas válidas 36 espécies Neotropicais de Trichopoda. Nesse estudo são redescritas ou descritas 22 espécies de Trichopoda e as três de Ectophasiopsis; para Trichopoda. Devido a falta de material não foram incluídas algumas espécies de Trichopoda. Neste estudo são propostas novas sinonímias, combinações novas, revalidações de espécies e novas espécies descritas. Ectophasiopsis Townsend, 1915, gênero monotípico, também foi revisado e uma espécie de Trichopoda foi transferida para Ectophasiopsis, assim como uma nova espécie descrita. Ectophasiopsis também está sendo posicionado no grupo “Trichopoda typica”, o qual está sendo redefinido, com novas características e nova composição. São apresentadas chaves de identificação para os 3 gêneros do grupo “Trichopoda typica”, assim como chaves de identificação para espécies de Trichopoda e de Ectophasiopsis. São apresentadas fotos dos machos e fêmeas de todas as espécies estudadas, assim como ilustrações de quase todas as terminálias masculinas e femininas / Trichopoda Berthold, 1827, is a Tachinidae genus belonging to the subfamily Phasiinae, originally distributed in the Americas. The Phasiinae species are Hemiptera parasitoids, especially Heteroptera, and have great importance in biological control. The genus is included in the “Trichopoda typica” group sensu Sabrosky (1950), together with the genus Eutrichopoda Townsend, 1908. The genus Trichopoda includes several nominal species, many which have been synonymized, while some were transferred to different genera. Even though the group is morphologically remarkable and also very important from an agricultural point of view, there is no revisionary work dealing with its species. Prior to the present study, 22 Neotropical valid species were included in Trichopoda, divided in two subgenera. With this current study 36 Neotropical species of Trichopoda are considered valid. In this study 22 species of Trichopoda and all three of Ectophasiopsis are redescribed or described; in Trichopoda. Due to lack of material some Trichopoda species were not included. In this study, we propose new synonyms, new combinations, and new revalidations, and describe new species. Ectophasiopsis Townsend, 1915, a monotypic genus, is also revised, and one Trichopoda specie is being transferred to it, and also a new specie is described. Ectophasiopsis is now being placed in the “Trichopoda typica” group, this genus-group is being redefined here, with new characters and a new composition. We provide identification keys for the three genera of the “Trichopoda typica” group, as well as identification keys to species of Trichopoda and Ectophasiopsis. We present photographs of males and females of all studied species, as well as illustrations of almost all male and female terminalia
130

A taxonomic and geographic study of the genus Xanthoparmelia in the Karoo

Brusse, Franklin Andrej 12 January 2015 (has links)
No description available.

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