Diss. / Bibliogr. p. 287-320.

Proporciona los pasos y procedimientos para acceder al recurso Springer Link.

Retinal dysplasia has been documented in many breeds of dogs. It has recently been hypothesized that Miniature Schnauzer dogs affected with retinal dysplasia and associated persistent hyperplastic primary vitreous have a decreased amount of Tfam and several mtDNA transcripts in the retina and RPE. Affected dogs were also hypothesized to have a decrease in leukocyte mtDNA compared to normal dogs. Additionally, using electron microscopy, these dogs were hypothesized to having decreased mitochondrial numbers and size with altered morphology in multiple tissues, including neutrophils. Due to these recent discoveries in this breed it has been proposed that retinal dysplasia could be the result of an altered energy supply to the retina and RPE. The objective of this study was to further investigate the pathogenesis of retinal dysplasia in the Miniature Schnauzer and English Springer Spaniel dog.<p> The hypothesis of an altered Tfam gene sequence in affected Miniature Schnauzer dogs leading to a decreased amount of Tfam transcript in the retina and RPE was tested by amplifying, cloning and sequencing the coding, 5 and 3non-coding regions, and intron 1 of the Tfam gene from affected and normal Miniature Schnauzer dogs. Using transmission electron microscopy, affected and normal lymphocyte mitochondria were also objectively measured and quantified in this breed along with mitochondrial morphology assessment. In the English Springer Spaniel dog, the hypothesis of a decreased amount of leukocyte mtDNA in affected dogs was tested using real-time PCR. In addition, using transmission electron microscopy, affected and normal lymphocyte mitochondria were objectively measured and quantified in this breed with mitochondrial morphology assessment.<p> Sequencing of the particular regions of the Miniature Schnauzer Tfam gene revealed no significant nucleotide changes between affected and normal dogs. Evaluation of lymphocyte mitochondrial size, number and morphology also revealed no significant differences between the two groups. In the English Springer Spaniel dog a relative decrease in leukocyte mtDNA did not exist in dogs affected with retinal dysplasia. Furthermore, evaluation of affected English Springer Spaniel dog lymphocyte mitochondria revealed no significant differences in mitochondrial number, surface area or morphology when compared to normal English Springer Spaniel dogs.<p> To conclude, we failed to demonstrate a mutation in the areas of the Tfam gene sequenced in Miniature Schnauzers affected with retinal dysplasia and associated persistent hyperplastic primary vitreous. In contrast to previous findings of decreased leukocyte mtDNA in the affected Miniature Schnauzer dog, no evidence was found to support a relative decrease in leukocyte mtDNA in English Springer Spaniel dogs affected with retinal dysplasia. Furthermore, the hypothesis of altered mitochondrial size, number and morphology in affected dogs is not supported by this study. Further evaluation of mitochondria, mtDNA and mitochondrial gene expression within age-matched retina and RPE of Miniature Schnauzer and English Springer Spaniel dogs is necessary to determine if mitochondria and altered energy supply play a role in the pathogenesis of retinal dysplasia in these breeds.

Retinal dysplasia has been documented in many breeds of dogs. It has recently been hypothesized that Miniature Schnauzer dogs affected with retinal dysplasia and associated persistent hyperplastic primary vitreous have a decreased amount of Tfam and several mtDNA transcripts in the retina and RPE. Affected dogs were also hypothesized to have a decrease in leukocyte mtDNA compared to normal dogs. Additionally, using electron microscopy, these dogs were hypothesized to having decreased mitochondrial numbers and size with altered morphology in multiple tissues, including neutrophils. Due to these recent discoveries in this breed it has been proposed that retinal dysplasia could be the result of an altered energy supply to the retina and RPE. The objective of this study was to further investigate the pathogenesis of retinal dysplasia in the Miniature Schnauzer and English Springer Spaniel dog.<p> The hypothesis of an altered Tfam gene sequence in affected Miniature Schnauzer dogs leading to a decreased amount of Tfam transcript in the retina and RPE was tested by amplifying, cloning and sequencing the coding, 5 and 3non-coding regions, and intron 1 of the Tfam gene from affected and normal Miniature Schnauzer dogs. Using transmission electron microscopy, affected and normal lymphocyte mitochondria were also objectively measured and quantified in this breed along with mitochondrial morphology assessment. In the English Springer Spaniel dog, the hypothesis of a decreased amount of leukocyte mtDNA in affected dogs was tested using real-time PCR. In addition, using transmission electron microscopy, affected and normal lymphocyte mitochondria were objectively measured and quantified in this breed with mitochondrial morphology assessment.<p> Sequencing of the particular regions of the Miniature Schnauzer Tfam gene revealed no significant nucleotide changes between affected and normal dogs. Evaluation of lymphocyte mitochondrial size, number and morphology also revealed no significant differences between the two groups. In the English Springer Spaniel dog a relative decrease in leukocyte mtDNA did not exist in dogs affected with retinal dysplasia. Furthermore, evaluation of affected English Springer Spaniel dog lymphocyte mitochondria revealed no significant differences in mitochondrial number, surface area or morphology when compared to normal English Springer Spaniel dogs.<p> To conclude, we failed to demonstrate a mutation in the areas of the Tfam gene sequenced in Miniature Schnauzers affected with retinal dysplasia and associated persistent hyperplastic primary vitreous. In contrast to previous findings of decreased leukocyte mtDNA in the affected Miniature Schnauzer dog, no evidence was found to support a relative decrease in leukocyte mtDNA in English Springer Spaniel dogs affected with retinal dysplasia. Furthermore, the hypothesis of altered mitochondrial size, number and morphology in affected dogs is not supported by this study. Further evaluation of mitochondria, mtDNA and mitochondrial gene expression within age-matched retina and RPE of Miniature Schnauzer and English Springer Spaniel dogs is necessary to determine if mitochondria and altered energy supply play a role in the pathogenesis of retinal dysplasia in these breeds.

Zugl.: Berlin, Humboldt-Univ., Diss., 2006

La thèse consiste de deux parties. Dans la première partie, on montre la pureté des fibres de Springer affines pour $\gl_{4}$ dans le cas non-ramifié. Plus précisément, on construit une famille de pavages non standard en espaces affines de la grassmannienne affine, qui induisent des pavages en espaces affines de la fibre de Springer affine. Dans la deuxième partie, on introduit une notion de $\xi$-stabilité sur la grassmannienne affine $\xx$ pour le groupe $\gl_{d}$, et on calcule le polynôme de Poincaré du quotient $\xx^{\xi}/T$ de la partie $\xi$-stable $\xxs$ par le tore maximal $T$ par une processus analogue de la réduction de Harder-Narasimhan. / This thesis consists of two parts. In the first part, we prove the purity of affine Springer fibers for $\gl_{4}$ in the unramified case. More precisely, we have constructed a family of non standard affine pavings for the affine grassmannian, which induce an affine paving for the affine Springer fiber. In the second part, we introduce a notion of $\xi$-stability on the affine grassmannian $\xx$ for the group $G=\gl_{d}$, and we calculate the Poincaré polynomial of the quotient $\xx^{\xi}/T$ of the stable part $\xxs$ by the maximal torus $T$ by a process analogue to the Harder-Narasimhan reduction.

La thèse consiste de deux parties. Dans la première partie, on montre la pureté des fibres de Springer affines pour $\gl_{4}$ dans le cas non-ramifié. Plus précisément, on construit une famille de pavages non standard en espaces affines de la grassmannienne affine, qui induisent des pavages en espaces affines de la fibre de Springer affine. Dans la deuxième partie, on introduit une notion de $\xi$-stabilité sur la grassmannienne affine $\xx$ pour le groupe $\gl_{d}$, et on calcule le polynôme de Poincaré du quotient $\xx^{\xi}/T$ de la partie $\xi$-stable $\xxs$ par le tore maximal $T$ par une processus analogue de la réduction de Harder-Narasimhan.

El webinar nos permitirá conocer la plataforma de Springer link y los principales tipos de recurso que ofrece, el proveedor nos mostrará las diferentes estrategias que se pueden utilizar para buscar información en la plataforma.

Ce travail de thèse a pour but de construire et d’étudier une fibration de Hitchin pour les groupes qui apparaît naturellement lorsque l’on essaie de géométriser la formule des traces. On commence par construire une telle fibration en utilisant le semi-groupe de Vinberg. Sur ce semi-groupe de Vinberg, on montre qu’il existe un certain morphisme « polynôme caractéristique » muni d’une section naturelle, de même que dans le cas des algèbres de Lie. On montre également que l’on peut construire un centralisateur régulier au-dessus de cette base des polynômes caractéristiques qui est un schéma en groupes commutatif et lisse.On s’intéresse alors à des variantes pour les groupes des fibres de Springer affines pour lesquelles on remarque que l’introduction du semi-groupe de Vinberg permet d’obtenir une condition d’intégralité analogue à celle de Kazhdan-Lusztig. Ces fibres de Springer affines sont des analogues locaux des fibres de Hitchin. On obtient alors une formule de dimension pour ces fibres.Dans un troisième temps, on s’intéresse à l’aspect global de cette fibration pour laquelle on donne une interprétation modulaire et sur laquelle on construit l’action d’un champ de Picard, issu du centralisateur régulier. L’espace total de cette fibration étant en général singulier, nous étudions son complexe d’intersection. Cet espace de Hitchin s’obtient naturellement comme l’intersection du champ de Hecke avec la diagonale du champ des G-torseurs et on démontre que sur un ouvert suffisamment gros de la base de Hitchin, le complexe d’intersection de l’espace de Hitchin s’obtient par restriction de celui du champ de Hecke corrrespondant.Enfin, dans la dernière partie de cette thèse, on établit un théorème du support dans le cas où l’espace total est singulier analogue à celui de Ngô et l’on démontre que, dans le cas de la fibration de Hitchin, les supports qui interviennent sont reliés aux strates endoscopiques. / This main goal of this work is to construct and study the properties of Hitchin fibration for groups which appears naturally when we try to geometrize the trace formula. We begin by constructing this fibration using the Vinberg’s semigroup. On this semigroup, we show that there exists a characteristic polynomial morphism equipped with a natural section, analog at the Kostant’s one in the case of Lie algebras. We also show that there exists on the base of characteristic polynomials a regular centralizer scheme, which is a smooth commutative group scheme.Then, we are interested in some variant of affine Springer fibers, for which we see that the Vinberg’s semigroup appears naturally to obtain an integrality condition analog to Kazhdan-Lusztig’s one. These affine Springer fibers are local incarnation of Hitchin fibers.In a third time, we go back to the global case and give a modular interpretation of this new Hitchin fibration on which we construct an action of a Picard stack, coming from the regular centralizer.The total space of this fibration, even on the generically regular semisimple locus will be singular and we want to understand his intersection complex. This space can be obtained as the intersection of the Hecke stack with the diagonal of the stack of G-bundles and we show that on a sufficiently big open subset of the Hitchin base, the intersection complex of the Hitchin’s space is the restriction of the corresponding intersection complex on the Hecke stack.Finally, in the last part of this work, we establish a support theorem in the case of a singular total space, generalizing Ngo’s theorem et we show that in the case of Hitchin fibration, the supports that appear are related to the endoscopic strata.

The diploma thesis The publishing house Axel Springer and its transformation into a digital house focuses on the gradual transformation of a the German publishing house Axel Springer from a traditional publisher of printed media into the digital house it is today. The thesis analyzes its business activities and offers a periodized overview of the house's dominant business strategies from the moment it was established in 1946 to 2014. Simultaneously, the thesis presents the chronological development of the house's product portfolio. It is this record of the house's historical and current portfolio which discovers not only the changes in the structure of revenues, but also the house's shift from its original object of enterprise. In the case of Axel Springer, the transformation is characterized with a transfer of the principles of media enterprise into the digital environment - within which the focus was broadened from media projects to non-media projects as well. Economically speaking, this strategy has been successful, as in 2014 the house generated more than 70% of its overall profit (EBITDA) from its digital activities. At the same time the thesis proves in a critical manner that the digital transformation of Axel Springer is not a result of successful digital transformation of the way the...