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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.
1

Divergências morfométricas entre populações isoladas de Melipona subnitida Ducke (hymenoptera: Apidae) no semiárido. / Morphometric differences between isolated populations of Melipona subnitida Ducke (hymenoptera: Apidae) in the semiarid.

SOUSA, José Aldenor de. 29 May 2018 (has links)
Submitted by Deyse Queiroz (deysequeirozz@hotmail.com) on 2018-05-29T18:46:19Z No. of bitstreams: 1 JOSÉ ALDENOR DE SOUSA - DISSERTAÇÃO PPGSA PROFISSIONAL 2014..pdf: 1307578 bytes, checksum: c7064a40d0c4cd6a65251e2fac21f6e0 (MD5) / Made available in DSpace on 2018-05-29T18:46:19Z (GMT). No. of bitstreams: 1 JOSÉ ALDENOR DE SOUSA - DISSERTAÇÃO PPGSA PROFISSIONAL 2014..pdf: 1307578 bytes, checksum: c7064a40d0c4cd6a65251e2fac21f6e0 (MD5) Previous issue date: 2014 / Este trabalho teve por objetivo realizar um estudo morfométrico desta espécie de abelha criada em condições artificiais no semiárido brasileiro, com a finalidade de verificar divergência em sua morfologia, de forma a identificar possíveis variações dessa espécie. As abelhas foram coletadas de criadores de abelhas sem ferrão distintos, de duas localidades sendo uma delas o município de São João do Rio do Peixe, Paraíba-PB, sob as coordenadas: lat. 06° 43' 44" S e long. 38° 26' 56" W. E a outra no município de Mossoró sob as coordenadas lati. 5°03'40’’ S, long. 37º23'51’ W. Distantes 262 quilômetros entre si. O período da pesquisa compreendeu os meses de dezembro de 2013 a janeiro do ano de 2014.Foram selecionados aleatoriamente 10 cortiços para nível de coletas dos insetos em cada localidade. Foram coletadas 60 abelhas operárias, sendo 3 abelhas referentes a cada cortiço. Os parâmetros avaliados dentro do estudo morfométrico foram: Comprimento Transversal, Comprimento Longitudinal, Pernas Coletoras Asas Anteriores Asas Posteriores e Peso por Inseto. Em relação a características avaliadas foram constatadas diferenças significativas entre todas quando se trata dos indivíduos das duas localidades. Corroborando a existência de variabilidade morfométricas entre as localidades. Na análise discriminante obtida para classificação de indivíduos entre as localidades, o município de são João do Rio do Peixe obteve uma taxa de classificação Correta de 100,0%, já para Mossoró a taxa foi de 96,67%, sendo que a média geral foi de 98,33%. Pela validação cruzada, estas localidade tiveram, respectivamente, identificação correta de seus indivíduos com taxas de 100% e 93,33%. A média geral da validação cruzada foi de 96,97%. As variações de tamanho encontradas neste trabalho constatadas pela morfometria demonstram que as técnicas são ferramentas importantes na avaliação e no desenvolvimento de estratégias de conservação e de sustentabilidade. / This work was aimed to carry out a morphometric study of this species of bee created in artificial conditions in semi-arid, with the purpose of verifying divergence in its morphology, in order to identify possible variations of this species. Bees were collected from beekeepers without distinct sting of two locations one being the country of São João do Rio do Peixe, Paraíba-PB under the coordinates: lat. 06 ° 43 '44 "S and long. 38 ° 26' 56" W. And the other in the country of Mossoró in the coordinates lati. 5 ° 03'40'' S, long. 37 ° 23'51 "W. 262 km distant from each other. The research was conducted in the period from December 2013 to January of the year 2014. From which 10 artificial nests were randomly selected for level of collections of insects in each location. 60 worker bees were collected, 3 bees for each nest. The morphometric parameters evaluated in the study were: Length Transverse, Longitudinal length, collecting Legs, Wings Earlier, Wings Beyond and Weight by Insect. In relation the characteristics evaluated significant differences among all when it comes to individuals of both locations were found. Confirming the existence of morphometric variability between locations. in discriminant analysis obtained for classification of individuals between locations, the country of São João do Rio do Peixe, obtained a correct classification rate of 100.0%, while for Mossoró rate was 96.67%, while the overall average was 98.33% .By cross-validation, this locality had, respectively, correct identification of individuals with their rates of 100% and 93.33%. The overall average of the cross-validation was 96.97%. Size variations found in this study noted by morphometry demonstrated that these techniques are important tools in the evaluation and development of strategies for the conservation and sustainability.
2

Biosystematic studies in the family Cyperaceae / Biosystematic studies in the family Cyperaceae

KOŠNAR, Jan January 2013 (has links)
The thesis was focused on the microevolutionary mechanisms that contribute to morphological diversity in selected members of the sedge family (Cyperaceae). Natural hybridization, evidenced from both morphological characters and molecular markers, was revealed to be a potentially important source of diversification in the tropical spikerushes of Eleocharis subgenus Limnochloa. High levels of phenotypic plasticity of clonal growth but rare genetic (ecotypic) differentiation among contrasting morphotypes were found in the polymorphic species Carex nigra, which implied that taxonomic splitting of the species was unreasonable.
3

Étude des réseaux neuronaux et des mécanismes cognitifs impliqués dans les déficiences intellectuelles liées au chromosome X / Study of neuronal networks and cognitive mecanisms involved in X linked intellectual disability

Curie, Aurore 08 April 2011 (has links)
Grâce aux progrès de la génétique moléculaire qui ont permis d’identifier de nouveaux gènes de déficience intellectuelle liée à l’X, il nous a été possible de travailler sur des groupes homogènes de malades présentant une mutation dans le même gène. Nous avons d’une part, pu mettre en évidence un dysfonctionnement du circuit cérébello-thalamo-préfrontal grâce à une étude en IRM morphométrique réalisée chez des patients ayant une mutation dans le gène Rab-GDI. D’autre part, nous avons identifié un phénotype tout à fait spécifique lié aux mutations du gène ARX, tant clinique que neuropsychologique, et cinématique, associant une atteinte très particulière de la motricité distale des membres supérieurs et du langage. La préhension des patients est pathognomonique, avec une préférence pour la pince pouce-majeur, une difficulté accrue pour l’utilisation du bord cubital de la main, et un trouble de la pronosupination. Sur le plan neuroanatomique, il existe une diminution de volume des noyaux gris centraux et des épaisseurs corticales des régions contrôlant la motricité, bien corrélées au paramètres de cinématique. Enfin, nous avons exploré les stratégies de raisonnement des patients déficients intellectuels atteints du syndrome de l’X fragile, d’une mutation du gène ARX ou de trisomie 21 en élaborant un paradigme de raisonnement visuel analogique issu des matrices de Raven. Nous en avons établi la trajectoire développementale. Les stratégies utilisées par les patients (étude en eyetracking) sont différentes de celles des contrôles y compris de même âge mental, avec un défaut d’inhibition majeur, encore plus franc chez les patients X fragiles que ceux porteurs de trisomie 21 / Thanks to progress in molecular genetics, that allowed identification of new genes responsible for X linked intellectual disability, we studied on homogeneous groups of patients presenting with a mutation in one or the other gene. In the first section, we showed dysfunction of cerebello-thalamo-prefrontal networks, thanks to morphological MRI study performed on patients with a mutation in the Rab-GDI gene. In the second section, we highlighted a very specific phenotype related to ARX gene mutations, clinically, neuropsychologically, and kinematically, with a very peculiar impairment of upper limbs distal motricity, and language disorder. Patients hand-grip is pathognomonic, with a preference for the middle finger instead of the index for the grip of object, major impairment of fourth finger use, and lack of pronation movements. Neuroimaging study showed decreased volume of basal ganglia, and cortical thickness of motor regions, well correlated to kinematic parameters. In the third section, we explored reasoning strategies in three groups of patients with intellectual deficiency: fragile X, ARX mutated and Down syndrome patients and controls (both chronological and mental age-matched subjects). We notably elaborated a visual analogical reasoning paradigm, inspired from Raven’s matrices. We established a developmental trajectory of this paradigm. The strategy used by patients (eyetracking study) was different from the one used by controls, with a huge lack of inhibition, even greater for fragile X patients than for Down syndrome patients

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