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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.
181

Risks in new product development (NPD) projects

Akram Afzal, Muhammad January 2017 (has links)
New product development (NPD) is vulnerable to a wide variety of risks arising from within the firm or from the external environment. Existing categorizations of NPD project risks are partial or ill-defined and consequently there is no clear consensus among researchers and practitioners about what constitute NPD project risks. To address this gap, this thesis deploys a systematic literature methodology to inductively develop a comprehensive risk taxonomy from a review of 124 empirical studies. This taxonomy is then empirically validated through a survey capturing data from 263 NPD projects conducted by UK firms. The thesis further investigated the moderating effect of NPD project type (incremental or radical), firm size (SMEs and large firms) and industry sectors on the proposed risk taxonomy. Variation in the perceptions of NPD risk by different members of the team was explored as well. The findings revealed that the principal risk factors affecting NPD projects are technological rapidity risk, supply chain risk, lack of funding and resource risk. The risk profile of radical NPD projects differed to that of incremental projects. SMEs were more vulnerable to NPD project risks than large firms. Most risks influenced NPD projects equally across industrial sectors. Members of NPD project teams from different backgrounds or with different roles perceived risks differently. The proposed taxonomy and its subsequent empirical validation provides a comprehensive and robust taxonomy for identifying and managing risks associated with different types of NPD project conducted by firms of varying sizes from different industrial sectors.
182

Free Classification of Dysarthric Speech: A Taxonomical Approach

January 2012 (has links)
abstract: Often termed the "gold standard" in the differential diagnosis of dysarthria, the etiology-based Mayo Clinic classification approach has been used nearly exclusively by clinicians since the early 1970s. However, the current descriptive method results in a distinct overlap of perceptual features across various etiologies, thus limiting the clinical utility of such a system for differential diagnosis. Acoustic analysis may provide a more objective measure for improvement in overall reliability (Guerra & Lovely, 2003) of classification. The following paper investigates the potential use of a taxonomical approach to dysarthria. The purpose of this study was to identify a set of acoustic correlates of perceptual dimensions used to group similarly sounding speakers with dysarthria, irrespective of disease etiology. The present study utilized a free classification auditory perceptual task in order to identify a set of salient speech characteristics displayed by speakers with varying dysarthria types and perceived by listeners, which was then analyzed using multidimensional scaling (MDS), correlation analysis, and cluster analysis. In addition, discriminant function analysis (DFA) was conducted to establish the feasibility of using the dimensions underlying perceptual similarity in dysarthria to classify speakers into both listener-derived clusters and etiology-based categories. The following hypothesis was identified: Because of the presumed predictive link between the acoustic correlates and listener-derived clusters, the DFA classification results should resemble the perceptual clusters more closely than the etiology-based (Mayo System) classifications. Results of the present investigation's MDS revealed three dimensions, which were significantly correlated with 1) metrics capturing rate and rhythm, 2) intelligibility, and 3) all of the long-term average spectrum metrics in the 8000 Hz band, which has been linked to degree of phonemic distinctiveness (Utianski et al., February 2012). A qualitative examination of listener notes supported the MDS and correlation results, with listeners overwhelmingly making reference to speaking rate/rhythm, intelligibility, and articulatory precision while participating in the free classification task. Additionally, acoustic correlates revealed by the MDS and subjected to DFA indeed predicted listener group classification. These results beget acoustic measurement as representative of listener perception, and represent the first phase in supporting the use of a perceptually relevant taxonomy of dysarthria. / Dissertation/Thesis / M.S. Communication Disorders 2012
183

Perlidae (Plecoptera) da Serra de Paranapiacaba, Estado de São Paulo : integrando informações morfológicas e moleculares na identificação de espécies /

Almeida, Lucas Henrique de. January 2018 (has links)
Orientador: Pitágoras da Conceição Bispo / Banca: Sérgio Nascimento Stampar / Banca: Lucas Silveira Lecci / Resumo: Plecoptera compreende uma ordem de insetos aquáticos com aproximadamente 3500 espécies conhecidas, sendo distribuídas em 16 famílias. No Brasil são registradas apenas duas famílias, sendo Gripopterygidae e Perlidae. Neste trabalho foram estudadas as espécies de Perlidae da Serra de Paranapiacaba, incluindo os Parques Estaduais Carlos Botelho (PECB), Intervales (PEI) e Turístico do Alto Ribeira (PETAR), Estado de São Paulo. Com o objetivo de integrar o conhecimento taxonômico ao molecular, obtendo identificações de adultos e a associação adulto-ninfa utilizando DNA Barcode. Foram registradas 14 espécies, sendo Anacroneuria representado por nove espécies: A. boraceiensis, A. debilis, A. fiorentini, A. flintorum, A. iporanga, A. itajaimirim, A. polita, A. subcostalis e A. tupi. Kempnyia por quatro espécies: K. auberti, K. colossica, K. flava e K. neotropica. Macrogynoplax por apenas uma espécie: M. veneranda. Foram realizados dois novos registros (Anacroneuria debilis e A. fiorentini), duas descrições de imaturos (A. flintorum e A. tupi) e uma sinonimização (Kempnyia petersorum). Adicionalmente, é fornecida uma chave de identificação de adultos da região / Abstract: Plecoptera comprises an order of aquatic insects with aproximately 3500 species, distributed in 16 families. In Brazil, only two families are recorded, being Gripopterygidae and Perlidae. In this work, were studied the species of Perlidae from Paranapiacaba mountains, including the Carlos Botelho State Park (PECB), Intervales State Park (PEI), and Alto Ribeira Tourist State Park (PETAR), São Paulo State. With the objective of integrating the taxonomic knowledge to the molecular, obtaining identifications of adults and the adult-nymph association using the DNA Barcode. Were recorded fourteen species, being Anacroneuria represented by nine species: A. boraceiensis, A. debilis, A. fiorentini, A. flintorum, A. iporanga, A. itajaimirim, A. polita, A. subcostalis and A. tupi. Kempnyia by four species: K. auberti, K. colossica, K. flava and K. neotropica. Macrogynoplax by only one species: M. veneranda. Were made two new records (Anacroneuria debilis and A. fiorentini), two descriptions of nymphs (A. flintorum and A. tupi), and one synonymization (Kempnyia petersorum). In addition, a key is provided for the identification of adults from the region / Mestre
184

Phylogeny of Grey-bellied Pygmy Mouse (\kur{Mus triton}) complex

KRÁSOVÁ, Jarmila January 2014 (has links)
The Grey-bellied Pygmy Mouse (Mus triton) has been for a long time considered as a single species, although validity of the single species status was questioned. In order to revise current taxonomy of M. triton, I analyzed sequences of one mitochondrial (cytochrome b) and two nuclear genes (IRBP and Intron 7 of the fibrinogen) from specimens collected across the most of its known distributional range. Four well-supported phylogroups at species level, differentiated during the Plio-Pleistocene, were evidenced. Divergence dating suggests that the diversification of "triton" species complex was likely caused by Plio-Pleistocene climatic oscillations together with highly diverse topography of Eastern Africa
185

New insights in the morphology and phylogeny of heterocytous cyanobacteria from Peru, including the description of new taxa

MENDOZA CARBAJAL, Leonardo Humberto January 2018 (has links)
Morphology and phylogeny for 36 heterocytous cyanobacterial strains are studied. Discussion with morphological, ecological, and phylogenetically related taxa is given for each strain. Potentially new genera and species are found, one of them being proposed as a novel genus.
186

Descrição e análise comparativa de larvas do gênero Physalaemus Fitzinger, 1826 (Amphibia, Anura, Leiuperidae)

Gomes, Joice 03 September 2013 (has links)
Submitted by Johnsson Rodrigo (r.johnsson@gmail.com) on 2013-09-03T03:42:03Z No. of bitstreams: 1 JOICE_GOMES_DEFINITIVA.pdf: 24606703 bytes, checksum: e837e6f8690a3db96b4b09c3c9c9e527 (MD5) / Approved for entry into archive by Alda Lima da Silva(sivalda@ufba.br) on 2013-09-03T17:57:33Z (GMT) No. of bitstreams: 1 JOICE_GOMES_DEFINITIVA.pdf: 24606703 bytes, checksum: e837e6f8690a3db96b4b09c3c9c9e527 (MD5) / Made available in DSpace on 2013-09-03T17:57:33Z (GMT). No. of bitstreams: 1 JOICE_GOMES_DEFINITIVA.pdf: 24606703 bytes, checksum: e837e6f8690a3db96b4b09c3c9c9e527 (MD5) / FAPESB / Na última revisão taxonômica do gênero Physalaemus Fitzinger, 1826, baseada em características morfológicas de espécimes adultos, foi sugerida que as espécies fossem alocadas em sete grupos de espécies (grupo de Physalaemus albifrons, grupo de P. cuvieri, grupo de P. deimaticus, grupo de P. gracilis, grupo de P. henselii, grupo de P. olfersii e grupo de P. signifer). Atualmente o gênero é composto por 45 espécies das quais 27 apresentam suas larvas descritas e para apenas dez são apresentadas descrições da morfologia oral interna. Visando contribuir para a resolução de problemas taxonômicos e sistemáticos, o objetivo principal deste estudo descrever e comparar larvas do gênero Physalaemus utilizando-se de caracteres da morfologia externa, oral externa e oral interna. No primeiro e segundo capítulos, as larvas de P. albifrons e P. angrensis são descritas. No terceiro capítulo, a morfologia oral interna de 11 espécies é estudada, descrita e comparada. No quarto capítulo, uma análise comparativa da morfologia externa, oral externa e oral interna de 20 larvas é feita. A partir da análise de cluster (UPGMA), utilizando como distância o índice de Gower, obteve-se grau de dissimilaridade de 45% entre os girinos amostrados. Os girinos de P. angrensis, P. camacan, P. signifer e P. spiniger formaram um grupo distinto, compartilhando muitos carcateres, corroborando o grupo morfológico proposto (grupo de Physalaemus signifer). Além disso, as larvas de P. crombiei e P. gracilis são muito semelhantes quanto a todos os aspectos morfológicos. Os girinos de P. signifer e P. jordanensis são os mais semelhantes quanto à morfologia externa; por outro lado, em relação à morfologia oral interna, P. signifer é muito semelhante à de P. angrensis, e os girinos de P. jordanensis compartilham poucos caracteres com as espécies. / Salvador
187

Estudo Taxonômico dos Holothuroidea (Echinodermata) de águas rasas da costa Brasileira

Martins, Luciana 04 September 2013 (has links)
Submitted by Johnsson Rodrigo (r.johnsson@gmail.com) on 2013-09-02T04:04:22Z No. of bitstreams: 1 LUCIANA.pdf: 5469390 bytes, checksum: 1a7d8c5d82205a72ef52c60d6514dd14 (MD5) / Approved for entry into archive by Alda Lima da Silva(sivalda@ufba.br) on 2013-09-04T19:31:44Z (GMT) No. of bitstreams: 1 LUCIANA.pdf: 5469390 bytes, checksum: 1a7d8c5d82205a72ef52c60d6514dd14 (MD5) / Made available in DSpace on 2013-09-04T19:31:45Z (GMT). No. of bitstreams: 1 LUCIANA.pdf: 5469390 bytes, checksum: 1a7d8c5d82205a72ef52c60d6514dd14 (MD5) / CAPES / A classe Holothuroidea (Echinodermata) possui cerca de 1400 espécies válidas. No Brasil, apenas 32 espécies são registradas, correspondendo, portanto, a menos de 3% do total de espécies conhecidas. O conhecimento atual sobre o filo Echinodermata no Brasil e na Bahia foi gerado, em sua maior parte, das grandes expedições que por aqui passaram ou de alguns trabalhos isolados. No Estado da Bahia são conhecidas 14 espécies de holoturoides todavia, a maioria destes registros foi realizada apenas na descrição original de cada uma destas espécies, ou seja, há mais de um século. Além de muito antigas, grande parte destas descrições foram baseadas em apenas um espécime ou em formas jovens, com poucas ou até mesmo nenhuma ilustração, dificultando ainda mais o entendimento do grupo e certamente perpetuando erros de identificação. Desta forma, o objetivo deste trabalho foi realizar um estudo taxonômico com os holoturóides que ocorrem no Estado da Bahia, caracterizando as espécies, identificando problemas taxonômicos, produzindo chaves de identificação e descrevendo novos táxons. Além de material obtido através de museus, foram realizadas coletas em diversas regiões do estado (região metropolitana de Salvador, Baía de Todos-os-Santos, Litoral Norte e Sul da Bahia), da zona entre-marés (coleta manual) ao infralitoral raso (20 m de profundidade por meio de mergulho livre e mergulho autônomo), e em regiões mais profundas (50 m) por dragagem com auxílio de amostrador de fundo do tipo van Veen. Quatro espécies tiveram o primeiro registro para o nordeste do Brasil — Isostichopus badionotus, Holothuria (Thymiosycia) arenicola, Pentamera pulcherrima e Stolus cognatus — e duas para o Atlântico Sul Ocidental — Holothuria (Theelothuria) princeps e Thyone pawsoni. Além disto, um gênero novo (Coronatum) e duas espécies novas (Cucumaria solangeae e Coronatum baiensis) foram descritas, e duas sinonímias e duas novas combinações foram propostas. Para cada espécie, apresenta-se diagnose e redescrição (quando necessário), notas ecológicas, localização do material-tipo e distribuição. Foram acrescentadas imagens (inéditas para a maioria) dos ossículos dérmicos em microscopia eletrônica de varredura, fotografia da espécie (in situ e fixada) e do anel calcário. Por fim, apresentam-se chaves de identificação para as ordens, famílias e espécies da classe Holothuroidea. / Salvador
188

Análise filogenética de três grupos de espécies de RHINOCRICUS KARSCH, 1881 (DIPLOPODA, SPIROBOLIDA, RHINOCRICIDAE) SENSU SCHUBART, 1951

Rodrigues, Patricia Elesbão da Silva January 2017 (has links)
Rhinocricus Karsch, 1881 possui atualmente 207 espécies descritas e distribuídas principalmente pelo continente americano, das quais 65 são descritas para o Brasil. A descrição do gênero foi baseada na presença de escobinas (depressões na porção distal dos prozonitos). O presente estudo avaliou a monofilia de três grupos de espécies previamente propostos em Rhinocricus. A matriz de dados foi composta por 39 caracteres morfológicos e 30 espécies terminais, sendo 21 como grupo interno e nove do grupo externo. Nós realizamos uma analise de parcimônia com pesos implicitos usando o software TNT e obtivemos a melhor árvore com a mesma topologia para três melhores valores de K (5.992, 7.309, 9.105). Nenhum dos três grupos de espécies de Rhinocricus foi recuperado monofilético. Rhinocricus (Erythocricus) sanguineostriatus foi recuperado irmão de todas as outras espécies, e Argentocricus Verhoeff, 1941 resultou parafilético. Os caracteres diagnósticos tradicionalmente utilizados para separar grupos de espécies, subgênero e gênero não foram recuperados como sinapomorfias. Ainda durante o exame do material quatro novas espécies de Rhinocricus foram descobertas e são aqui descritas. Futuras investigações incluindo amostras mais amplas de espécies são necessárias, para estabelecer hipóteses de relacionamento robustas entre R. (Erythocricus), Argentocricus, e o restante das espécies de Rhinocricus, deste modo identificando grupos monofiléticos no gênero e suas sinapomorfias. / Rhinocricus Karsch, 1881 currently has 207 species described and distributed mainly by the American continent, of which 65 are described for Brazil. The genus was based on the presence of scobinae (depressions in distal portion of prozonit). The present study evaluated the monophyly of three groups of species previously proposed in Rhinocricus. The data matrix was composed for 39 morphological characters and 30 species as terminal taxa, being 21 the ingroup, and nine the outgroup. We performed a parsimony analysis with implied weights using TNT software, obtaining the same best topology with three optimal K-values (5.992, 7.309, 9.105). None of the three previously proposed species groups of Rhinocricus was recovered monophyletic. Rhinocricus (Erythocricus) was recovered sister to all other species, and Argentocricus Verhoeff, 1941 resulted paraphyletic. The diagnostic characters traditionally used to separate species groups, subgenera, and genera were not recovered as synapomorphies. Still during the examination of the material four new species of Rhinocricus were discovered and here described. Further investigation including a broader species sample is needed attempting to establish robust relationship hypotheses between R. (Erythocricus), Argentocricus, and the remainder species of Rhinocricus, thus identifying the monophyletic groups in the genus and their synapomorphies.
189

O gênero xestoleberis sars, 1866 (crustacea-ostracoda) nas plataformas norte, nordeste e leste e no arquipélago de São Pedro e São Paulo, Brasil

Luz, Nathália Carvalho da January 2015 (has links)
Os ostracodes constituem um importante grupo de microcrustáceos que tem despertado o interesse tanto das biociências quanto das geociências. Para tanto, é fundamental o estudo taxonômico destes organismos e o entendimento de sua distribuição e ecologia. Os trabalhos realizados na plataforma continental brasileira muito têm contribuído para o conhecimento do grupo, que é bastante diverso. Porém, a riqueza e complexidade dos ostracodes ressaltam a necessidade de mais estudos também na plataforma. Em ilhas oceânicas brasileiras, as pesquisas com ostracodes ainda é muito recente, com poucos trabalhos publicados. A importância de estudar os ambientes insulares reside no fato de tais áreas colaborarem para o entendimento da diversidade, biogeografia e evolução dos organismos. O presente trabalho visa aumentar o conhecimento do grupo na plataforma continental do Brasil, mais especificamente nas regiões Norte, Nordeste e Leste, e no Arquipélago de São Pedro e São Paulo (ASPSP), através do estudo do gênero Xestoleberis Sars. Este gênero é bastante diversificado e amplamente distribuído em todos os oceanos, e, no Brasil, ocorre ao longo de toda a plataforma, além das ilhas oceânicas. Foi registrado um total de oito espécies nas áreas estudadas, sendo duas endêmicas ao ASPSP e seis pertencentes à plataforma. Das espécies encontradas na plataforma continental, quatro são novas, uma foi mantida em nomenclatura aberta e uma já havia sido previamente descrita. / The ostracods represent an important group of microcrustaceans that has aroused interest in biosciences and geosciences. For this, it is crucial the taxonomic study of these organisms and to understand their distribution and ecology. The works conducted in the Brazilian continental shelf contributed greatly to the knowledge of this group that is quite diverse. However, the great richness and complexity of ostracods highlight the need for more studies also in the platform. In the Brazilian oceanic islands, the searches on these crustaceans are still very recent, with a few numbers of published works. The study of insular habitat collaborates with the understanding of diversity, biogeography and evolution of the organisms. The present work aims to increase the knowledge of the group in the Brazilian continental shelf, specifically in the Northern, Northeastern and Eastern regions, and in the Archipelago of São Pedro and São Paulo (ASPSP), with the study of the genus Xestoleberis Sars. This genus is diversified and widely distributed in all oceans and in Brazil occurs along the entire shelf and in oceanic islands. Eight species were recorded in the study areas, two species are endemic to the ASPSP and six belong to the continental shelf. Among the platform species, four are new, one was maintained in open nomenclature and one was already described.
190

The biodiversity and biogeography of shallow-water flora and fauna of the Western Indian ocean : with special reference to the Polychaeta, Mollusca and Echinodermata

Richmond, Matthew D. January 1998 (has links)
The biodiversity and biogeography of the western Indian Ocean shallow-water marine flora and fauna was examined with special emphasis on Polychaeta, Mollusca (excluding Opisthobranchia) and Echinodermata. A collection of predominantly eulittoral polychaetes from Zanzibar and Mafia (Tanzania) revealed a minimum of91 species, of which 29 % are reported to occur across the Indian Ocean to the West Pacific, and 21 % are regarded as 'cosmopolitan'. Taxonomic problems associated with this taxon are discussed. Over 3,200 species of shelled Mollusca have been reported from the region, though the overall diversity of the groups are likely to be less due to the presence of many synonyms within the taxa which remain to be resolved. Of those families which have been taxonomically reviewed, it appears that the western Indian Ocean supports up to 15-20 % endemism, with noticeable differences in species diversity between the mainland of Africa and the western Indian Ocean islands, especially among bivalves. A total of 419 species of echinoderms are now known from this region, with 107 species (25 %) endemic. About 84 % of the nonendemic species are reported from several localities across the Indian Ocean to the West Pacific. Differences in the diversity of this group between mainland Africa-Madagascar and the western Indian Ocean islands are shown and possible reasons discussed. Origins of the marine macro-invertebrate taxa in the western Indian Ocean include the maintenance of ancient Tethyan Sea fauna and larval (or adult) dispersal across the northern Indian Ocean. The possibility of species diversity being a function of coastline length was briefly investigated. The preparation of A Guide to the Seashores of Eastern Africa and the Western Indian Ocean Islands, describing over 1,600 species, forms part of the work of this thesis and provides a baseline of taxonomic information for macrofauna and flora. From the latter, together with predictions provided by specialists, an estimate of about 10,000 species of shallow-water marine macrofauna and flora are found in this region. It is acknowledged that taxonomic problems affect many invertebrate taxa which require additional attention before estimates can be defined more precisely. Continued taxonomic research and dissemination of biodiversity findings are considered priorities to help stem the degradation and misuse of marine resources of this region resulting from human exploitation which is expected to increase considerably over the coming decades.

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