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1
Ecker, James Sherwood. "D+4." Xavier University / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=xavier1352821786.
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Elkouhen, Mehdi. "Modélisation géométrique 4-D appliquée à l'animation." Université Louis Pasteur (Strasbourg) (1971-2008), 2002. http://www.theses.fr/2002STR13206.
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Le contrôle de la forme et du genre de surfaces animées reste un problème difficile. En effet, représenter les objets par des surfaces implicites permet de créer des modifications topologiques sur les objets animés mais ne permet pas un contrôle précis de leur topologie. Par exemple, des trous ou des composantes déconnectées peuvent apparaître sur les objets animés. A l'inverse, représenter les objets des surfaces subdivisées en sommets, arêtes, faces rend très difficile la définition des modifications topologiques. Au LSIIT, nous représentons les animations par des objets 4-D; un film est extrait d'un objet 4-D par l'affichage de ses coupes par un ensemble d'hyperplans. C'est ce que nous appelons la modélisation géométrique 4-D ou l'animation 4-D. Ce modèle permet de créer des animations d'objets avec modifications topologiques mais soulève un nouveau problème. En effet pour une animation donnée, comment imaginer un objet 4-D qui le représente et comment construire cet objet? Dans cette thèse, nous nous sommes intéressés en particulier à la fusion de deux objets homéomorphes. Les développements ont été réalisés dans le modeleur STIGMA (Space-Time Interpolation for the Geometric Modelling of Animations). Dans la première partie, nous définissons un outil de déformation axial et un outil surfacique. Nous montrons ensuite qu'en courbant les objets construits par extrusion, il est facile de construire des fusions de deux objets identiques. Nous montrons aussi comment contrôler le chemin de la fusion ainsi que le nombre de zones de fusions entre les deux objets. Dans la seconde partie, nous définissons la primitive de construction d'objets 4-D appelée Métamorphose 4-D qui prend en paramètre deux objets homéomorphes et construit une animation qui transforme le premier objet en le deuxième. Ensuite, nous appliquons nos outils de déformation aux objets construits grâce à cet opérateur pour définir la fusion de deux objets de genres arbitraires mais homéomorphesThe control on the shape and topology of animated objects is a complex problem. When representing objects by implicit surfaces, it is possible to create animations with topological changes. But handles or disconnected components can appear on the animated objects. When representing objects by cellular surfaces, creating this kind of effects is hard and requires strong designer interaction. We represent animations by 4-D objects; a movie is extracted from a 4-D object by displaying its slices by a set of hyper-planes. This way of representing animations permits to construct animations with topological changes but creates a new problem. For a given animation, how can the designer imagine a 4-D object that defines it and construct it? In this thesis, we studied the merging of two homeomorphic objects. We developed a set of tools that we integrated to the space-time modeller of animations STIGMA (Space-Time Interpolation for the Geometric Modelling of Animations). In the first part, we describe a new 4-D tool defined by a Bezier curve and a tool defined by a Bezier rectangular surface. By bending objects constructed using the 4-D extrusion operator, we construct the merging of two identical objects. We also explain how to control the path of the merging and the number of areas where the two objects merge
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Kim, Jusub. "Efficient rendering of large 3-D and 4-D scalar fields." College Park, Md.: University of Maryland, 2008. http://hdl.handle.net/1903/8250.
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Thesis (Ph. D.) -- University of Maryland, College Park, 2008.Thesis research directed by: Dept. of Electrical and Computer Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Oak, James N. "Characterization of epitope-tagged dopamine D¦4 receptors." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape9/PQDD_0001/MQ45554.pdf.
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Nunes, Luciana AngÃlica da Silva. "VisÃo supersimÃtrica de modelos topolÃgicos e Branas em D=4 e D=5." Universidade Federal do CearÃ, 2008. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=2587.
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FundaÃÃo de Amparo à Pesquisa do Estado do CearÃCoordenaÃÃo de AperfeiÃoamento de NÃvel Superior
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico
A linha principal dessa tese relaciona-se com teorias supersimÃtricas. Junta-se à essa linha principal uma discussÃo sobre propagadores de campos de Kalb-Ramond em branas. Na realidade os campos anti-simÃtricos sÃo outro fio condutor deste trabalho, aparecendo em quase todos os tÃpicos. Inicialmente, em branas do tipo delta de Dirac, tÃpicas dos modelos de Dvali de Randall-Sundrum, mostramos que a relaÃÃo que ocorre entre os propagadores de campos vetoriais em D=4 e D=5 dimensÃes espaÃo-temporais, continua vÃlida quando tratamos campos tensoriais anti-simÃtricos. Tal resultado subsidia especulaÃÃes de que campos tensoriais podem ser localizados na brana. No que tange a teorias com supersimetria, nossas investigaÃÃes se dividem em trÃs direÃÃes, a saber: 1) modelos topolÃgicos em D=5, no contexto da chamada pseudo-supersimetria, 2) construÃÃo de uma descriÃÃo plena do superespaÃo em D=5, inÃdita na literatura, a qual denominamos de superespaÃo intrÃnseco, para diferenciar da proposta de pseudo-supersimetria em D=5, 3) descriÃÃo do efeito Aharanov-Casher em uma teoria supersimÃtrica em D=4 com termo de quebra de Lorentz. Quanto a modelos topolÃgicos, realizamos a extensÃo pseudosupersimÃtrica em D=5, de um termo com estrutura anÃloga ao termo de Chern-Simons, mas envolvendo apenas o campo tensorial de gauge de Kalb-Ramond . Obtivemos a expansÃo completa dos supercampos e demonstramos em detalhes o nÃmero de graus de liberdade do tensor anti-simÃtrico de rank-2 em D=5. Uma vez que construÃmos a expansÃo completa do supercampo de Kalb-Ramond, determinamos o parceiro fermiÃnico do termo topolÃgico 5-dimensional. Por outro lado, insatisfeitos com o formalismo existente na literatura para tratar sistemas com supersimetria em (4+1) dimensÃes, especialmente tendo em vista aplicaÃÃes em teorias de branas, construÃmos o formalismo de superespaÃo N=1 - D=5. Encontramos os geradores, e, conseqÃentemente, as derivadas covariantes de supersimetria e mostramos que existe uma dependÃncia explÃcita da quinta coordenada. Este à um resultado que permite propagaÃÃo na dimensÃo extra, a qual nÃo à descrita no formalismo de pseudosupersimetria uma vez que sÃo usadas as mesmas derivadas covariantes de supersimetria de quatro dimensÃes. Escrevemos o Modelo de Wess-Zumino em cinco dimensÃes usando o formalismo de supersimetria intrÃnseca, assim como um supercampo vetorial, o que permitiu a construÃÃo de uma teoria manifestamente supersimÃtrica em D=5 com invariÃncia de gauge. Por fim, no contexto de uma teoria supersimÃtrica em D=4, utilizamos um ansatz para quebrar a simetria de Lorentz, simplesmente impondo que determinado campo do modelo à constante, ao mesmo tempo em que a supersimetria à preservada. Adicionamos o termo de Fayet-Illiopoulos, que nos fornece um potencial e a partir da presenÃa desse potencial escrevemos uma nova lagrangiana que permite obter o efeito Aharonov-Casher em uma teoria supersimÃtrica com termo de quebra de Lorentz. Vale a pena mencionar ainda, quatro apÃndices, a saber: convenÃÃo e revisÃo de espinores; formas diferenciais para supercampos; a prova detalhada da existÃncia de trÃs graus de liberdade on-shell em D=5 para o campo de Kalb-Ramond; e Ãlgebra de deSitter nas representaÃÃes vetorial e espinorial SO(1,4).
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Nunes, Luciana Angélica da Silva. "Visão supersimétrica de modelos topológicos e Branas em D=4 e D=5." reponame:Repositório Institucional da UFC, 2008. http://www.repositorio.ufc.br/handle/riufc/12776.
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NUNES, Luciana Angélica da Silva. Visão supersimétrica de modelos topológicos e Branas em D=4 e D=5. 2008. 149 f. Tese (Doutorado em Física) - Programa de Pós-Graduação em Física, Departamento de Física, Centro de Ciências, Universidade Federal do Ceará, Fortaleza, 2008.Submitted by Edvander Pires (edvanderpires@gmail.com) on 2015-06-09T18:32:55Z No. of bitstreams: 1 2008_tese_lasnunes.pdf: 763396 bytes, checksum: 53059041868576ba43dd7ecbe7f29e5c (MD5)
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A linha principal dessa tese relaciona-se com teorias supersimétricas. Junta-se à essa linha principal uma discussão sobre propagadores de campos de Kalb-Ramond em branas. Na realidade os campos anti-simétricos são outro fio condutor deste trabalho, aparecendo em quase todos os tópicos. Inicialmente, em branas do tipo delta de Dirac, típicas dos modelos de Dvali de Randall-Sundrum, mostramos que a relação que ocorre entre os propagadores de campos vetoriais em D=4 e D=5 dimensões espaço-temporais, continua válida quando tratamos campos tensoriais anti-simétricos. Tal resultado subsidia especulações de que campos tensoriais podem ser localizados na brana. No que tange a teorias com supersimetria, nossas investigações se dividem em três direções, a saber: 1) modelos topológicos em D=5, no contexto da chamada pseudo-supersimetria, 2) construção de uma descrição plena do superespaço em D=5, inédita na literatura, a qual denominamos de superespaço intrínseco, para diferenciar da proposta de pseudo-supersimetria em D=5, 3) descrição do efeito Aharanov-Casher em uma teoria supersimétrica em D=4 com termo de quebra de Lorentz. Quanto a modelos topológicos, realizamos a extensão pseudosupersimétrica em D=5, de um termo com estrutura análoga ao termo de Chern-Simons, mas envolvendo apenas o campo tensorial de gauge de Kalb-Ramond . Obtivemos a expansão completa dos supercampos e demonstramos em detalhes o número de graus de liberdade do tensor anti-simétrico de rank-2 em D=5. Uma vez que construímos a expansão completa do supercampo de Kalb-Ramond, determinamos o parceiro fermiônico do termo topológico 5-dimensional. Por outro lado, insatisfeitos com o formalismo existente na literatura para tratar sistemas com supersimetria em (4+1) dimensões, especialmente tendo em vista aplicações em teorias de branas, construímos o formalismo de superespaço N=1 - D=5. Encontramos os geradores, e, conseqüentemente, as derivadas covariantes de supersimetria e mostramos que existe uma dependência explícita da quinta coordenada. Este é um resultado que permite propagação na dimensão extra, a qual não é descrita no formalismo de pseudosupersimetria uma vez que são usadas as mesmas derivadas covariantes de supersimetria de quatro dimensões. Escrevemos o Modelo de Wess-Zumino em cinco dimensões usando o formalismo de supersimetria intrínseca, assim como um supercampo vetorial, o que permitiu a construção de uma teoria manifestamente supersimétrica em D=5 com invariância de gauge. Por fim, no contexto de uma teoria supersimétrica em D=4, utilizamos um ansatz para quebrar a simetria de Lorentz, simplesmente impondo que determinado campo do modelo é constante, ao mesmo tempo em que a supersimetria é preservada. Adicionamos o termo de Fayet-Illiopoulos, que nos fornece um potencial e a partir da presença desse potencial escrevemos uma nova lagrangiana que permite obter o efeito Aharonov-Casher em uma teoria supersimétrica com termo de quebra de Lorentz. Vale a pena mencionar ainda, quatro apêndices, a saber: convenção e revisão de espinores; formas diferenciais para supercampos; a prova detalhada da existência de três graus de liberdade on-shell em D=5 para o campo de Kalb-Ramond; e álgebra de deSitter nas representações vetorial e espinorial SO(1,4).
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Ménard, Geneviève. "Effets des leucotriènes D¦4 sur les macrophages alvéolaires." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0018/MQ49110.pdf.
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Garmy, Jean-Pierre. "Syndrome parasellaire aigü révélateur d' adénome hypophysaire : 4 observations." Clermont-Ferrand 1, 1987. http://www.theses.fr/1987CLF13031.
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Le syndrome de compression parasellaire brutal révélateur d' adénome hypophysaire est étudié à propos de 4 observations, comparées à 55 cas de la littérature. Révélateur pour 1,7 à 2,6 % des adénomes décrits, il associe des signes ophtalmologiques (100%), neurologiques (93% dont céphalée : 61%) et endocriniens. Le diagnostic est précisé par la tomodensitométrie, parfois l' artériographie, voire la résonance magbétique nucléaire. La sévérité des signes visuels peut nécessiter une décompression neuro-chirurgicale en plus du traitement médical. La guérison est de règle mais le plus souvent au prix de séquelles ophtalmologiques et endocriniennes. Lorsque la nécrose est imcomplète, l' histologie permet de reconnaitre par ordre de fréquence décroissante : prolactinome, adénome somatotrope, adénome corticotrope. La physiopathologie de l' apoplexie est complexe et à coté des classiques phénomènes vasculaires, apparait la notion récente d' auto-immunité antéthypophysaire (hypophysite).
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BRAND'EL, SYLVAIN. "Conception et implantation d'un modeleur 4-d pour l'animation." Université Louis Pasteur (Strasbourg) (1971-2008), 2000. http://www.theses.fr/2000STR13031.
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Parmi toutes les methodes d'animation, certaines sont particulierement adaptees a autoriser les modifications topologiques. Certaines metamorphoses, les surfaces implicites, ou encore les objets espace-temps comportent de telles modifications. Dans le cadre des objets espace-temps, pour permettre de telles animations, et plus generalement pour ne pas restreindre le type d'animation possible, il est necessaire de recourir a un ensemble d'operations qui permettent de modeliser des objets 4-d de forme et de structure topologique quelconque. Le travail effectue est la conception et l'implantation d'un modeleur geometrique d'objets 4-d qui regroupe un tel ensemble d'operations, offrant un controle precis de l'animation en agissant directement sur l'objet 4-d. Ce modeleur, baptise stigma (pour space-time interpolation for the geometric modelling of animations), comporte une interface utilisateur specifique concue pour l'animation qui appuie sur la perception et la visualisation des objets 4-d. Stigma comporte des operations de construction d'objets 4-d et des operations de modification du plongement. La premiere categorie regroupe des primitives de construction d'objets surfaciques et volumiques simples, des operations topologiques, telles que les operations inherentes aux cartes generalisees, le modele topologique utilise, ou la fusion, et des operations de changement de dimension. Ces derniers operateurs, tres souvent utilises, sont l'extrusion et l'epaississement (augmentation de la dimension), et l'operation de coupe (diminution de la dimension), qui permet d'extraire des animations des objets espace-temps modelises. La seconde categorie, plus restreinte, regroupe les operations modifiant la geometrie d'objets prealablement modelises, et non leur topologie. Ces operations sont principalement les transformations et le modele de deformation dogme. La diversite des resultats obtenus montre bien l'etendue des possibilites offertes par les objets 4-d.
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Ludovici, Matteo <1979>. "Studi su modelli supersimmetrici con N=1 in d=4." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2011. http://amsdottorato.unibo.it/3894/.
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Vaitiulionytė, Diana. "Furo[2,3-d]pirimidinų sintezė ir savybės." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2006. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2006~D_20060613_174528-81935.
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We report herein on the results of N- and O-alkylation of 5-cyano-2-methylsulfanyl-4(3H)- pyrimidinone with 4-substituted ω-bromoacetophenones. Synthesized N-(phenacyl)-4- pyrimidinones and 4-(phenacyloxy)pyrimidines with suitable substituents in pyrimidine ring are versatile synthons for the preparation of fused pyrimidine heterocycles. Chemical properties of new furo[2,3-d]pyrimidines were investigated. The structure of synthesized compounds was confirmed by data of 1H NMR, IR and UV spectra.
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Ait, Amrane Samir. "Sur le schéma de Hilbert des courbes gauches de degré d et genre g = (d-3)(d-4)/2." Paris 11, 1998. http://www.theses.fr/1998PA112375.
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Pour classifier les courbes gauches (localement de Cohen Macaulay mais pas nécessairement lisses) en géometrie algébrique, on étudie le schéma de Hilbert H_d,g qui paramètre les familles de courbes de degré d et genre g. Dans cette thèse, nous étudions ce schéma, que l'on note alors X_d, dans le cas g = (d-3)(d-4)/2, qui est le premier cas intéressant en genre grand. Pour étudier le schéma de Hilbert H_d,g, M. Martin-Deschamps et D. Perrin ont proposé dans plusieurs articles une philosophie qui repose sur un invariant algébrique des courbes qu'on appelle le module de Rao. Leur philosophie consiste a stratifier ce schéma de Hilbert par les sous-schémas a cohomologie constante sur lesquels on dispose d'un morphisme lisse qui à une courbe associe son module de Rao. Pour commencer, nous montrons que le module de Rao de toute courbe de X_d est de "Koszul" grâce à des résultats de P. Ellia et S. Nollet, et nous donnons pour chaque valeur de d tous les modules de Rao obtenus avec les courbes de X_d. Cela constitue l'étape du bas de la philosophie évoquée ci-dessus. L'étape intermédiaire qui est la suivante, consiste a passer de ces modules aux sous-schémas a cohomologie constante de X_d, via le morphisme ci-dessus. Nous montrons que ces sous-schémas sont tous irréductibles, lisses et nous calculons leurs dimensions. Nous déduisons ensuite les composantes irréductibles de X_d et nous décrivons leurs courbes génériques. Enfin, la partie la plus difficile de la thèse correspond à l'étape du haut, et consiste à étudier les spécialisations entre les différents sous-schémas à cohomologie constante de X_d en utilisant la notion de triade récemment introduite par R. Hartshorne, M. Martin-Deschamps et D. Perrin, ce qui permet notamment de montrer la connexité de X_d. Cela revient a construire des familles de courbes qui joignent ces sous-schémas, ce qui est parfois long et complexe. Nous proposons pour cela une démarche permettant de réaliser pratiquement les constructions.
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Azizi, Mohammed. "Simulations numériques du modèle d'Ising de 1,5 à 4 dimensions détermination des quantités critiques sur fractal, D=1,5 et en théorie des champs, D=2,3, 4." Grenoble 2 : ANRT, 1986. http://catalogue.bnf.fr/ark:/12148/cb37595627z.
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Sackmann, Brandon S. "Remote Assessment of 4-D Phytoplankton Distributions off the Washington Coast." Fogler Library, University of Maine, 2007. http://www.library.umaine.edu/theses/pdf/SackmannBS2007.pdf.
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Pedemonte, S. "4-D tomographic inference : application to SPECT and MR-driven PET." Thesis, University College London (University of London), 2014. http://discovery.ucl.ac.uk/1429290/.
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Emission tomographic imaging is framed in the Bayesian and information theoretic framework. The first part of the thesis is inspired by the new possibilities offered by PET-MR systems, formulating models and algorithms for 4-D tomography and for the integration of information from multiple imaging modalities. The second part of the thesis extends the models described in the first part, focusing on the imaging hardware. Three key aspects for the design of new imaging systems are investigated: criteria and efficient algorithms for the optimisation and real-time adaptation of the parameters of the imaging hardware; learning the characteristics of the imaging hardware; exploiting the rich information provided by depthof- interaction (DOI) and energy resolving devices. The document concludes with the description of the NiftyRec software toolkit, developed to enable 4-D multi-modal tomographic inference.
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Zachariah, Elizabeth. "4-D Modeling of Displacement Vector Fields for Improved Radiation Therapy." VCU Scholars Compass, 2010. http://scholarscompass.vcu.edu/etd/2323.
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In radiation therapy, it is imperative to deliver high doses of radiation to the tumor while reducing radiation to the healthy tissue. Respiratory motion is the most significant source of errors during treatment. Therefore, it is essential to accurately model respiratory motion for precise and effective radiation delivery. Many approaches exist to account for respiratory motion, such as controlled breath hold and respiratory gating, and they have been relatively successful. They still present many drawbacks. Thus, research has been expanded to tumor tracking. This paper presents a spatio-temporal model for four dimensional CT reconstruction. The method begins with a set of initial CT projections and a simultaneously acquired breathing trace. Two methods are explored to model the spatial components: principal component analysis and a pseudoinverse matrix method. An iterative approach is used to match the simulated projections to the actual projections. The simulated projections and the initial projections are evaluated using Normalized Root Mean Square Error (NRMSE). The proposed method shows simulated projections and actual projections match, and as such the model is able to accurately predict the deformation.
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Giménez, Oya Víctor. "Molecular studies of two methylerythritol 4-phosphate pathway enzymes of isoprenoid biosynthesis : the 4-diphosphocytidyl-2C-methyl-D-erythritol kinase and the 1-deoxy-D-xylulose 5-phosphate synthase = Estudios moleculares de dos enzimas de la ruta del metileritritol 4-fosfato de biosíntesis de isoprenoides : la 4-difosfocitidil-2C-metil-D-eritritol quinasa y la 1-dexosi-D-xilulosa 5-fosfato sintasa." Doctoral thesis, Universitat de Barcelona, 2009. http://hdl.handle.net/10803/665005.
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Los isoprenoides son una de las mayores familias de compuestos descritos en la naturaleza. Estos compuestos están presentes en todos los organismos vivos y se sintetizan a partir de dos moléculas de 5 átomos de carbono: el isopentenil difosfato (IPP) y el dimetilalil difosfato (DMAPP). Actualmente se conoce que arqueobacterias, hongos y animales presentan la ruta del mevalonato de síntesis de estos precursores, mientras que eubacterias, algún protozoo (como el causante de la malaria) y protistas presentan la ruta del metileritritol 4-fosfato (MEP) de síntesis de IPP y DMAPP. Estas rutas coexisten separadas espacialmente en plantas, helechos y algunas algas. La ruta del MEP de biosíntesis de los precursores de isoprenoides se muestra como una atractiva diana para la búsqueda de nuevos compuestos antimaláricos, antibióticos y herbicidas debido a su presencia en los principales agentes patogénicos y su ausencia en animales, además del carácter esencial de los isoprenoides para la vida. En esta tesis se ha realizado la búsqueda asistida por ordenador de compuestos que puedan interferir en la formación del complejo homodimérico del cuarto paso enzimático de la ruta del MEP. La metodología utilizada es muy útil en la búsqueda de inhibidores específicos. Se han caracterizado la unión de diferentes compuestos obtenidos con la enzima. Además se ha caracterizado el estado de oligomerización de la enzima. Paralelamente también se ha caracterizado un homólogo del primer paso enzimático de la ruta del MEP de un organismo termofílico caracterizando sus principales parámetros cinéticos y residuos importantes para la actividad enzimática mediante mutagénesis dirigida. Como último punto, se ha caracterizado el proceso de proteólisis de diferentes homólogos de este primer paso enzimático de la ruta del MEP asociándolo a modificaciones postraduccionales intramoleculares de las mismas proteínas, abriendo la posibilidad de un proceso de regulación posttraduccional de la actividad enzimática en este tipo de enzimas.
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Peters, Siegfried. "Zum gezielten Aufbau höherer [beta]-(1-]4)-Galactooligosaccharide [Beta-(1-]4)-Galactooligosaccharide] und zur manno-selektiven Hydridreduktion acylierter [beta]-D-Glycosid-2-ulosen [Beta-D-Glycosid-2-ulosen]." [S.l. : s.n.], 2002. http://elib.tu-darmstadt.de/diss/000212.
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Carey, Annette T. "Purification and characterization of tomato exo-(1 ->4)-#beta#-D-galactanase." Thesis, University of Nottingham, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339672.
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Al-Mosawi, Mohammed. "Towards a 4-D spatial and temporal model of human enamel biomineralisation." Thesis, Queen Mary, University of London, 2018. http://qmro.qmul.ac.uk/xmlui/handle/123456789/41764.
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Precise timings and spatial progression of human enamel biomineralisation are still largely unknown due to scarcity of developing human enamel specimens available for investigation. This information is crucial for optimising emerging biomimetic regenerative and reparative dentistry routes. Five developing permanent incisors were obtained from an archaeological source and used alongside mature contemporary teeth for comparison. X-ray microtomography (XMT), synchrotron X-ray diffraction (S-XRD) and quantitative back-scattered electrons (qBSE) imaging were used to investigate the mineral density distribution, the crystallites texture magnitude and orientation and the nanostructure of dental enamel at various developmental stages, respectively. XMT revealed that there was a bi-directional mineralisation "front" that starts at the cusp tip and at the enamel-dentine junction (EDJ) travelling cervically and peripherally until the relative mineral density is uniform in the fully mature tooth (2.75 g/cm3 ± 0.01 g/cm3). S-XRD revealed that within one probed region, two populations of crystallite orientations exist simultaneously with an angular separation of 20-50°, with one population being more dominant than the other by a factor of approximately 3:7. Furthermore, one population displayed a higher degree of crystallite texture than the other. These phenomena were observed in all stages of tooth development. The crystallites in both populations were oriented approximately perpendicular to the EDJ regardless of development stage, indicating initial preferred directions of crystallites persist from early through to full maturation. The direction and magnitude of organisation within two distinct populations of crystallites within the developing and mature enamel has not been quantified previously. qBSE analyses suggested that the two observed populations are most likely due to prism decussation and revealed that mineralisation of prism cores precedes that of prism boundaries. These results provide new insights towards building a quantitative spatio-temporal model of human enamel biomineralisation in order to inform emerging biomimetic reparative/regenerative dental technologies.
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Im, Soohyun. "Correlating Structural Heterogeneity to Properties of Metallic Glasses Using 4-D STEM." The Ohio State University, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=osu1618865204994021.
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Чорноус, В. О. "Синтез 4-аміно-5-хлоро-2,6-дигідропіроло[3,4-d]піридазин-2-oнів." Thesis, БДМУ, 2021. http://dspace.bsmu.edu.ua:8080/xmlui/handle/123456789/18540.
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Depenthal, Claudia. "Entwicklung eines zeitreferenzierten 4-D-Kalibrier- und Prüfsystems für kinematische optische Messsysteme." [S.l. : s.n.], 2008. http://digbib.ubka.uni-karlsruhe.de/volltexte/1000010086.
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Wiedau, Kayla N. "ASSESSING SENSITIVITY OF HORSERADISH PLANTS TO DICAMBA AND 2,4-D IN NEW SOYBEAN PRODUCTION SYSTEMS." OpenSIUC, 2017. https://opensiuc.lib.siu.edu/theses/2208.
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Collinsville, Illinois is the leading producer of horseradish is the nation. The river bottom geography surrounding Collinsville, Illinois near St. Louis, Missouri is a high-production area for horseradish. The development of soybean technologies resistant to dicamba or 2,4-D may allow horseradish growers to gain control of troublesome weeds, such as Palmer amaranth (Amaranthus palmeri) or volunteer horseradish, but could pose risks as well. Drift of these two herbicides or carryover to horseradish could cause severe injury and possible crop loss. While synthetic auxin-tolerant soybean may also allow growers to control volunteer horseradish, herbicide efficacy may differ depending on the volunteer horseradish variety. These risks and benefits could affect the adoption rate of these new soybean technologies in horseradish production areas. A field trial was established in 2015 in Edwardsville, IL and 2016 Medora, IL to simulate drift of both dicamba and 2,4-D onto horseradish. Applications were made in horseradish to mimic drift of a mid-post emergence application in soybean onto the horseradish crop. Plants were monitored for injury and stand, height, and yield reductions throughout the season. Individual roots were evaluated post-harvest. Overall, 2,4-D caused more injury at all rates when compared to dicamba. Horseradish growers may see yield reductions if rates at or greater than 1/1000X of a field rate of 2,4-D drift onto their fields. Not planting horseradish near a 2,4-D-tolerant soybean field, as well as reading the herbicide labels and following application requirements, should help growers prevent serious injury and yield loss. On the other hand, rates of 2,4-D at or above a full field rate offered complete control of all plants; therefore, growers who struggle with persistent volunteer horseradish could rotate to a 2,4-D-tolerant soybean and gain needed control of those plants. Field experiments were conducted in 2014, 2015, and 2016 to investigate the impact of dicamba residues following applications in a dicamba-tolerant soybean crop on horseradish planted the following season. Carryover trials were conducted as two-year rotations of soybean followed by horseradish in Collinsville, Illinois. Multiple rates of dicamba were applied at several timings in dicamba-tolerant soybean and the crop was monitored for injury. The following season horseradish was planted and monitored for injury and stand, height, and yield reductions. No injury or reductions were observed with any treatment in either year, potentially indicating a lack of dicamba remaining in the soil. Horseradish plant stand counts, height as well as yields were not reduced when compared to the nontreated. Results from this experiment suggest that rotating from dicamba-tolerant soybean to horseradish should pose no threat to horseradish. Greenhouse experiments were carried out in 2016 in three separate runs. Each run consisted of three replications of five varieties of horseradish, 604, 788, 9705, Hungarian, and V7E3, and two rates of dicamba, glyphosate, and dicamba plus glyphosate . Plants were sprayed when at least one plant in each pot had reached a height of 17 to 23 cm. Horseradish was then rated for injury at 3, 7, 14, 21, and 28 days after treatment (DAT). Heights were also taken at 0, 14, and 28 DAT. At 28 DAT plants were harvested, weighed and place in a dryer for 72 hours and weighed again. The lowest level of injury at 28 DAT was with variety 604. The control of horseradish roots is critical to ensure the plant is killed completely and does not return the following season as a volunteer. The concerns associated with auxin-tolerant crops can be mitigated with proper management of herbicides and crop locations. While off target movement of 2,4-D may cause damage to a horseradish crop, it could be used as a herbicide to control volunteer horseradish. Additionally, if a grower chooses to use a dicamba-tolerant soybean variety, they may have the choice to use a dicamba plus glyphosate premix which will also give good control of volunteer horseradish with little concerns of dicamba carryover to the subsequent horseradish crop. Capitalizing on the strengths and weaknesses of each technology will help horseradish growers manage many weeds and facilitate the production of this important specialty crop.
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Beildeck, Marcy Ellen. "The role of vitamin D and the vitamin D receptor in TCF-4 regulation and silencing of CYP24A1." Connect to Electronic Thesis (CONTENTdm), 2009. http://worldcat.org/oclc/454140383/viewonline.
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Marjoshi, Delphine. "Investigating the effects of three herbicides - Kamba, 2,4-D and Roundup on Salmonella enteric serovar Typhimurium growth and antibiotic tolerance phenotypes." Thesis, University of Canterbury. School of Biological Sciences, 2014. http://hdl.handle.net/10092/10284.
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Herbicides are a common tool in weed control. With the introduction of genetically modified herbicide-tolerant crops, there has been a dramatic increase in the use of particular herbicides. Herbicides contaminate the environment and food and feed and can come into contact with non-target organisms, especially bacteria. Salmonella enteric serovar Typhimurium, which is a human and animal pathogen, was chosen to investigate if the commercial formulations of three herbicides – Kamba, 2,4-D and Roundup are toxic to bacteria and whether sub-lethal concentrations cause a response to antibiotics. In addition, earlier work demonstrating an effect of salicylic acid on antibiotic response was reconfirmed in this study.
The herbicides were toxic to S. typhimurium at concentrations above the manufacturers recommended application rates. A key finding of this study was that when S. typhimurium was grown in sub-lethal concentrations of the herbicides, it demonstrated a change in its susceptibility to various antibiotics. Kamba and 2,4-D caused increased tolerance of chloramphenicol, tetracycline, ampicillin and ciprofloxacin and increased sensitivity to kanamycin. Exposure to Roundup caused increased sensitivity to chloramphenicol and tetracycline and increased tolerance towards kanamycin and ciprofloxacin. Roundup had no measureable affect on ampicillin susceptibility.
The minimum concentrations of herbicides that induced an antibiotic response were within the recommended application rates. Furthermore, the minimum 2,4-D concentration that induced tetracycline, chloramphenicol and ampicillin tolerance was at or below the maximum residue limits set for food and feed commodities. Simultaneous exposure to an herbicide and an antibiotic was necessary for the induction of antibiotic tolerance. In addition, the effect of the herbicide on the antibiotic response was faster than the lethal effect of the antibiotics. Kamba induced chloramphenicol, tetracycline, ampicillin and ciprofloxacin tolerance was maintained in the absence of Kamba once tolerance was induced by simultaneous exposure to Kamba and antibiotic.
The emergence of antibiotic tolerance is an important health issue that may compromise treatment of serious bacterial infections. The widespread use of herbicides in agricultural, urban and domestic settings increases the number of bacteria that are exposed to herbicides. The tolerance induced by the herbicides may increase the frequency of antibiotic tolerant strains, increase the chance of co-exposure to antibiotics, and increase the potential for failure to treat bacterial infections as a result.
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Zimmermann, Timo. "Analyse der Zellsortierung und Zellbewegung von Dictyostelium discoideum mittels konfokaler 4-D-Mikroskopie." [S.l.] : [s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=963688677.
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Stegner, Andrew L. "Drug resistance in D. discoideum isolation of 4-nitroquinoline 1-oxide resistant mutants /." Diss., Columbia, Mo. : University of Missouri-Columbia, 2005. http://hdl.handle.net/10355/4236.
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Thesis (M.A.)--University of Missouri-Columbia, 2005.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (July 14, 2006) Includes bibliographical references.
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Sætrom, Jon. "Hierarchical Ensemble Kalman Filter : for Observations of Production and 4-D Seismic Data." Thesis, Norwegian University of Science and Technology, Department of Mathematical Sciences, 2007. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-9617.
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Viljoen, Deon Walter. "The specification and design of a prototype 2-D MPEG-4 authoring tool." Thesis, University of Port Elizabeth, 2003. http://hdl.handle.net/10948/d1015741.
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The purpose of this project was the specification, design and implementation of a prototype 2-D MPEG-4 authoring tool. A literature study was conducted of the MPEG-4 standard and multimedia authoring tools to determine the specification and design of a prototype 2- D MPEG-4 authoring tool. The specification and design was used as a basis for the implementation of a prototype 2-D MPEG-4 authoring tool that complies with the Complete 2-D Scene Graph Profile. The need for research into MPEG-4 authoring tools arose from the reported lack of knowledge of the MPEG-4 standard and the limited implementations of MPEG-4 authoring tools available to content authors. In order for MPEG-4 to reach its full potential, it will require authoring tools and content players that satisfy the needs of its users. The theoretical component of this dissertation included a literature study of the MPEG-4 standard and an investigation of relevant multimedia authoring systems. MPEG-4 was introduced as a standard that allows for the creation and streaming of interactive multimedia content at variable bit rates over high and low bandwidth connections. The requirements for the prototype 2-D MPEG-4 authoring system were documented and a prototype system satisfying the requirements was designed, implemented and evaluated. The evaluation of the prototype system showed that the system successfully satisfied all its requirements and that it provides the user with an easy to use and intuitive authoring tool. MPEG-4 has the potential to satisfy the increasing demand for innovative multimedia content on low bandwidth networks, including the Internet and mobile networks, as well as the need expressed by users to interact with multimedia content. This dissertation makes an important contribution to the understanding of the MPEG-4 standard, its functionality and the design of a 2-D MPEG-4 Authoring tool. Keywords: MPEG-4; MPEG-4 authoring; Binary Format for Scenes.
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Ngala, Umar Jibrin. "4 D Delta Tectonics: Tectonic Evolution of the Deepwater South Central Niger Delta." Thesis, Royal Holloway, University of London, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.498744.
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Hult, Amanda, and Cassandra Schönberg. "Kommunala friskrivningar : En studie om hur kommunerna hanterar jordabalken 4 kap. 19 d §." Thesis, Högskolan Väst, Avdelningen för data-, elektro- och lantmäteriteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hv:diva-9883.
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En fastighetsaffär är en av de allra största och viktigaste investeringarna som kan ske i en människas liv. Det är därför viktigt att aktuell lagstiftning följs när dessa affärer genomförs. Efter att en fastighet har sålts är det inte ovanligt att det uppstår tvister och oklarheter kring vem som ansvarar för så kallade dolda fel i fastigheten. Dolda fel är något som kan uppmärksammas efter köpet. Enligt jordabalken gäller i normalfallet att säljaren ansvarar för dessa fel i 10 år från det att köpet gjordes. Säljaren kan undvika detta ansvar genom att friskriva sig från fel i fastigheten. Enligt jordabalken är sådana friskrivningar ogiltiga i de fall då en näringsidkare säljer en fastighet till en konsument. Enligt vår tolkning av lagen och dess förarbeten gäller detta även när kommuner säljer fastigheter till privatpersoner. I denna studie ska det undersökas hur väl kommunerna är medvetna om att denna begränsning i lagen finns och hur de såväl i praktiken som i teorin förhåller sig till den, vid fastighetsförsäljningar till privatpersoner. För att söka svar på frågorna ska en kombination av en juridisk och en kvalitativ metod använts. Totalt ska det under studiens gång granskas 46 stycken kontrakt från 10 olika kommuner. Studien baseras på en granskning av 46 stycken kontrakt, varav 52 % visade sig vara ogiltiga enligt JB 4 kap. 19 d. Vidare visade granskningen att majoriteten av dessa är utformade på ett av tre alternativa sätt, där samtliga innehöll minst en friskrivning från fel och brister i fastigheten. Studien visar även att stor okunskap råder i kommunerna angående hur regeln ska tolkas och hur denna typ av friskrivning därför bör hanteras i de kommunala kontrakten. Dessutom visar studien på att de ansvariga i kommunerna inte heller verkar vara medvetna om att samma syfte som de vill uppnå genom en friskrivning kan åstadkommas genom en grundlig förklarande beskrivning av köpeobjektet.Buying a property is one of the biggest and most important investments in a person´s life. When this kind of purchase is being performed it´s important that the Swedish legislation is being considered and followed correctly by both parties when writing the contract. After a property is sold it's not unusual that some disputes and uncertainties rises about who´s responsible for the so called "hidden defects" on the property, which can be found after the purchase has become final. According to Swedish law the seller is responsible for these defects for the following 10 years after the purchase is completed. However there is one way for the seller to avoid this kind of responsibility - by using a disclaimer from these hidden defects. When a trader is selling a property to a consumer, this kind of disclaimers, according to jordabalken (JB) 4 cap. 19 d §, is invalid. According to what the writers can interpret by reading the text of law and the legislative history, JB 4 cap. 19 d § also should be applied in those cases where a municipality is selling a property to a private individual. The purpose of this study is to map the municipalities awareness of the existence of the law and how they consider that the law should be handled when selling a property to a private individual. To seek the answers to these questions a combination of a juridical and a qualitative method have been used. During the study a total of 46 contracts from 10 different municipalities have been examined. The study came across a total of 46 disclaimers, which a percantage of 52 % according to JB 4 cap 19 d § considers as invalid. The majority of these disclaimers was proved to be designed as one of three alternative ways, where every one of them contained some kind of disclaimer from hidden defects and flaws in the property. The study proves that there is big ignorance and lack of knowledge at the municipalities about how the law in JB 4 cap. 19 d § should be interpreted and how this kind of disclaimer therefore should be treated in the contracts. Also, the study shows that the municipalities doesn't seem to be aware that the same purpose that they want to achieve by using the disclaimer, can be accomplished by a detailed description of the property.
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Oberthür, Markus. "Gezielter Aufbau von [beta](1-]4)-verknüpften [beta(1-]4)-verknüpften] Oligomeren der D-Galactose effiziente Wege zu Tri-, Tetra- und Hexagalactosiden /." [S.l. : s.n.], 1999. http://elib.tu-darmstadt.de/diss/000028/.
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Fahmi, Noureddine. "Nouvelles voies de synthèse des 2-désoxy-4-thio-D et L-pentofuranose et de 3'-azido-2', 3'-didésoxy-4'-thionucléosides." Amiens, 1996. http://www.theses.fr/1996AMIE0109.
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Le but de ce travail est la synthèse d'antiviraux de type 2'-désoxy-4'-thionucléosides et leurs analogues 3'-azido ou l'atome d'oxygène du cycle glucidique est remplacé par un atome de soufre. Ce choix résulte du fait que certains 4'-thionucléosides présentent d'intéressantes activités biologiques et une plus grande stabilité vis-à-vis d'enzymes catabolisant la liaison glycosidique. La première partie décrit la préparation de dérivés du 3-azido-2, 3-didésoxy-4-thio-d-érythro-pentofuranose obtenus à partir du D-xylose en 13 ou 14 étapes (rdt. Global=2,5%). Le groupement azido est introduit à un stade précoce de la synthèse selon une réaction de Mitsunobu. La condensation de bases pyrimidiques (thymine, 5-halogénouracile) sur les thiosucres par la méthode de Vorbruggen conduit aux 3'-azido-2', 3'-didesoxy-4'-thionucléosides (rdt=7 à 20%) et aux anomères avec des rendements du même ordre. La seconde partie relate une stratégie, plus générale, à partir du L-arabinose. Elle permet la préparation de dérivés du 2-désoxy-4-thio-D-érythro-pentofuranose et leurs analogues 3-azido en 10 étapes avec des rendements respectifs de 17 et 15%. La réaction d'hétérocyclisation, à partir du dérivé clé : le dibenzyl dithioacétal du 3,5-di-O-benzoyl-2-désoxy-L-thréo-pentose, conduit soit directement au thiosucre de la série D avec le systeme CDP/I2/imidazole, soit en deux étapes (iodation, cyclisation) au thiosucre de la série L avec le système PPH3/I2/imidazole. L’étude RMN réalisée sur les thiosucres et leurs dérivés nucléosidiques a permis d'attribuer les configurations anomériques et de montrer les limites des règles empiriques de Hudson fondées sur le signe des pouvoirs rotatoires. Les structures des 3'-azido-2', 3'-didésoxynucleosides ont été confirmées par spectrométrie de masse (FAB/MS).
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Ito, Noriyuki. "Concomitant Presence of p16/Cyclin-dependent Kinase 4 and Cyclin D/Cyclin-dependent Kinase 4 Complexes in LNCaP Prostatic Cancer Cell Line." Kyoto University, 2000. http://hdl.handle.net/2433/151432.
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White, David Charles. "Synthesis of 3-Aryl-2-(2-aryl-2-oxoethyl)pyrido[2,3-d]-4(3H)pyrimidones and 3-Aryl-2-(2-arylethenyl)pyrido[2,3-d]-4(3H)pyrimidones as Potential Antiepileptic Drugs." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/46506.
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A series of 2-alkyl-3-arylpyrido[2,3-d]pyrimidones were synthesized for testing as
potential antiepileptic drugs. The goal was to achieve better neurological activity and/or
lower toxicity than displayed by a series of 2-alkyl-3-aryl-4(3H)-quinazolinones prepared
previously in our research group. From the pharmacological testing data of these target
compounds, we have found that the additional nitrogen at the C-8 position of the quinazolinone
framework increased the anticonvulsant activity. However, the neurological toxicity increased
as well. The anticonvulsant and neurotoxic activity seen in the variuos 2-alkyl side chains
and 3-aryl substituents incorporated into these new pyridopyrimidones was consistent with the
activity observed with the same substituents on the 4(3H)-quinazolinones. The 3-aryl group
consists of various ortho-substituted phenyl rings, while the 2-alkyl chain consists of a
2-(2-aryl-2-oxo)ethyl or 2-arylethenyl group.Master of Science
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Tolson, Joshua Allen. "THE EFFECT OF INTEGRATED WEED MANAGEMENT STRATEGIES ON WEED POPULATIONS AND BIOMASS, PASTURE PRODUCTIVITY, ECONOMIC RETURNS, AND FORAGE QUALITY WITH AND WITHOUT GRAZING." UKnowledge, 2012. http://uknowledge.uky.edu/pss_etds/4.
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Field studies examined the strategies of mowing, herbicide, fertility, and all combinations on tall ironweed populations, weed biomass, pasture yield, grazing, economics, and forage quality at three Kentucky locations. Mowing was performed in July 2008 and 2009, herbicide applied in August 2008, and fertilizer applied in September 2008 and 2009 at all locations. Weed populations were measured in 2008, 2009, and 2010, and forage and weed biomass collected in May or June of 2009 and 2010. Herbicide treatments reduced weed biomass at all locations, and reduced tall ironweed stems by 64% or greater in 2009 at all locations. Weed biomass did not differ when comparing all treatments with and without mowing or treatments with or without fertilizer. Forage grass biomass produced was greatest with herbicide plus fertilizer and with the combination of mowing plus herbicide plus fertilizer at all locations in both years. Two years of grazing did not reduce weed populations. Grazing did reduce forage grass and clover biomass at one location, and weed biomass at two locations. Two locations had positive economic returns based on herbicide treatment for weed control and forge yield. Herbicide treatments reduced crude protein at one location and in-vitro true digestibility at two locations.
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Coelho, Ana Júlia Soares Dinis. "Testemunhos artísticos no vidro romano português." Master's thesis, Faculdade de Ciências Sociais e Humanas, Universidade Nova de Lisboa, 2012. http://hdl.handle.net/10362/7749.
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Dissertação apresentada para cumprimento dos requisitos necessários à obtenção do grau
de Mestre em História da Arte da AntiguidadeA presente dissertação tem como objetivo principal o estudo artístico de um corpus vítreo romano provindo do atual território nacional. A partir deste é feita a abertura de um campo de estudo em que se pretende partir da análise individual de cada peça, para a compreensão do todo. Promovendo por isso o confronto com outras áreas artísticas e a interdisciplinaridade. Pretende-se efetuar um novo olhar exploratório sobre as possibilidades artísticas do vidro.
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Vennström, Marie. "Crystal Chemistry of the Ti3Sn-D, Nb4MSi-D and Pd-Ni-P Systems." Doctoral thesis, Uppsala University, Department of Materials Chemistry, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-3466.
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Future energy systems based on hydrogen as energy carrier require reliable ways for storing hydrogen gas in safe, clean and efficient ways. Metal hydrides absorb hydrogen gas reversibly, making them suitable for storage applications. Investigations of the crystal structures of these materials contribute to an understanding of the factors which can influence the absorption.
Three systems, Ti3Sn-D, Nb4MSi-D (M=Co or Ni) and Pd-Ni-P, have been investigated in this thesis. Various solid state synthesis techniques have been used for sample preparation. The crystal structures have been studied using x-ray and neutron diffraction techniques.
Three metal hydride phases were found in the Ti3Sn-D system upon hydrogenation. Deuterium occupies titanium octahedra and the applied deuterium pressure induces the phase transitions. The distances between the deuterium atoms increase from 2.47 Å in orthorhombic Ti3SnD0.80 to 4.17 Å in cubic Ti3SnD.
The Nb4MSi-D system (M=Co or Ni) readily absorbs deuterium at room temperature and 90 kPa deuterium pressure to give a deuterium content of Nb4MSiD~2.5. Two interstitial voids, both coordinated by four niobium atoms arranged in a tetrahedral configuration, accommodate deuterium atoms.
Two ternary phases and a solid solution of nickel in Pd3P have been synthesised and the crystal structures determined. PdNi2P is orthorhombic and crystallises in the MgCuAl2-type structure: an ordered derivative of the Re3B-type structure. Pd8Ni31P16 is a tetragonal high-temperature phase stable at 700°C with 110 atoms in the unit cell. Pd2.7Ni0.3P0.94 has the cementite-type structure with mixed occupancy of palladium and nickel at one of the two non-equivalent crystallographic metal positions.
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MARSOLLA, L. D. "Avaliação da Adsorção do Herbicida 2,4-d em Carvão Ativado em Pó Utilizando Água Com Diferentes Qualidades." Universidade Federal do Espírito Santo, 2015. http://repositorio.ufes.br/handle/10/10309.
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Previous issue date: 2015-03-02O 2,4-diclorofenoxiacético (2,4-D) é um dos herbicidas mais consumidos no Brasil e é preferencialmente usado devido a sua boa seletividade e baixo custo. Possui alta toxidade e baixa biodegradabilidade, oferecendo risco à saúde humana e ao meio ambiente, podendo ser encontrado em solos, águas superficiais e subterrâneas. Estudos mostram que o tratamento convencional da água possui baixa eficácia na remoção de microcontaminantes, com isso várias técnicas têm sido utilizadas na remoção de compostos em água, como a adsorção por carvão ativado. Apresenta-se a adsorção em carvão ativado tem se demonstrado como tecnologia eficiente na remoção de diversos contaminantes, dentre eles os agrotóxicos. Assim, o presente trabalho objetivou avaliar a adsorção do 2,4-D por três carvões ativados em pó (CAP) em água ultrapura e em água bruta do Rio Santa Maria da Vitória. A quantificação do herbicida foi analisada por cromatografia líquida de alta eficiência, após concentração da amostra pelo método de extração em fase sólida. Os ensaios de adsorção foram realizados com carvões ativados derivados da casca de coco (CAP-01), pinus (CAP-02) e palha de café (CAP-03), que foram caracterizados e avaliados na sua capacidade de remoção do 2,4-D nas duas matrizes de água. Dois modelos de isoterma de adsorção, Langmuir e Freundlich, foram aplicados para descrever os dados de adsorção, que indicaram o CAP-02 como o carvão que apresentou a melhor capacidade de adsorção do 2,4-D entre os carvões estudados, tanto em água ultrapura quanto em água bruta. Nos ensaios realizados em água bruta, houve redução da adsorção do 2,4-D para as três amostras de CAP, quando comparado com os ensaios realizados em água ultrapura, indicando interferência de compostos, como a matéria orgânica, no processo de adsorção.
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Bélanger, Nancy. "Implication possible du récepteur dopaminergique D¦4 dans l'induction des dyskinésies chez les singes parkinsoniens." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ60611.pdf.
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Shih, Ping-Chang. "Joint variational camera calibration refinement and 4-D stereo reconstruction applied to oceanic sea states." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/52320.
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In this thesis, an innovative algorithm for improving the accuracy of variational space-time stereoscopic reconstruction of ocean surfaces is presented. The space-time reconstruction method, developed based on stereo computer vision principles and variational optimization theory, takes videos captured by synchronized cameras as inputs and produces the shape and superficial pattern of an overlapped region of interest as outputs. These outputs are designed to be the minimizers of the variational optimization framework and are dependent on the estimation of the camera parameters. Therefore, from the perspective of computer vision, the proposed algorithm adjusts the estimation of camera parameters to lower the disagreement between the reconstruction and 2-D camera recordings. From a mathematical perspective, since the minimizers of the variational framework are determined by a set of partial differential equations (PDEs), the algorithm modifies the coefficients of the PDEs based on the current numerical
solutions to reduce the minimum of the optimization framework. Our algorithm increases the tolerance to the errors of camera parameters, so the joint operations of our algorithm and the variational reconstruction method can generate accurate space-time models even using videos captured by perturbed cameras as input. This breakthrough prompts the realization of ocean surface reconstruction using videos filmed by remotely-controlled helicopters in the future. A number of techniques, technical or theoretical, are explored to fulfill the development and implementation of the algorithm and relative computation issues. The effectiveness of the proposed algorithm is validated through the statistics applied to real ocean surface reconstructions of data collected from an offshore platform at the Crimean Peninsula, the Black Sea. Moreover, synthetic data generated using computer graphics are customized to simulate various situations that are not recorded in the Crimea dataset for the demonstration of the algorithm.
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Rasolofonjatovo, Evelia. "Conception, synthèse et évaluation biologique d’ analogues contraints de l’isocombrétastatine a-4 à visée antitumorale." Thesis, Paris 11, 2011. http://www.theses.fr/2011PA114852.
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Les résistances aux traitements actuels contre le cancer imposent de trouver de nouvelles cibles thérapeutiques. Une de ces cibles est le réseau vasculaire assurant un apport suffisant en nutriments et en oxygène à la tumeur, et permettant l’apparition de métastases. Détruire la vascularisation de la tumeur par l’utilisation d’agents antivasculaires (VDA)revient à l’asphyxier et à l’affamer, inhibant ainsi la prolifération des cellules tumorales et empêchant le processus métastatique. L’objectif de ce travail de thèse a été d’étudier des analogues contraints de l’isocombrétastatine A-4 (isoCA-4), une molécule phare du laboratoire, ayant un excellent pouvoir d’inhibition de la polymérisation de la tubuline et présentant une activité antivasculaire. Ces structures dont la double liaison est incluse dans différents types de cycles C,ont été étudiées également afin d’évaluer l’influence de l’angle dièdre formé par les noyaux A et B sur les activités biologiques des divers types de structures. Préalablement sélectionnés par modélisation moléculaire, ces analogues contraints sont de type 1-arylnaphtalène, 5-arylbenzoxépine ou 4-arylchromène et ont été préparés par des voies d’ accès originales développées dans le cadre de cette thèse. Parmi les composés synthétisés, l’analogue de type benzoxépine 3-53est aussi cytotoxique que l’isoCA-4 et possède un pouvoir d’inhibition de la polymérisation de la tubuline équivalent. Une évaluation plus poussée de son profil biologique, ainsi que celle des meilleurs représentants de chaque série chimique est actuellement en coursMost tumor cells rely on an efficient vascular supply for their survival, making the tumor vasculature an attractive target for anti-cancer therapy. This thesis aimed at the design and synthesis of constrained analogues of isocombretastatin A-4(isoCA-4), an antivascular agent developed in the laboratory, which exerts excellent cytotoxicities against a large panel ofcancer cell lines, and strongly inhibits tubulin polymerization. Conformationally restricted analogues of isoCA-4,featuring 1-arylnaphthalene, 5-arylbenzoxepine or 4-arylchromene skeletons were designed by computational studies andprepared by novel synthetic strategies. Of all synthesized compounds, benzoxepine analogue 3-53 strongly inhibits tubulinpolymerization and shows excellent cytotoxicities against several human cancer cell lines
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Zhang, Honghai. "Segmentation And Computer-aided Diagnosis Of Cardiac MR Images Using 4-D Active Appearance Models." Diss., University of Iowa, 2007. https://ir.uiowa.edu/etd/154.
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The four-dimensional (4-D) cardiac MR images contain rich information about the static and dynamic properties of the heart, which were not fully utilized in clinical practice for quantitative analysis -- a difficult task for humans, which can be achieved by computer-aided image analysis and diagnosis. In this thesis, the 4-D Active Appearance Model (AAM) was used to achieve highly automated computer segmentation of the left and right ventricles (LV and RV) and the diagnosis of normal and tetralogy of Fallot (TOF) patients. The whole process was implemented in four stages: data construction, model construction, computer segmentation, and computer-aided diagnosis.
The data construction stage overcame most inherent limitations of cardiac MR imaging and produced high-quality 4-D ventricular image with isotropic voxels, complete coverage and no respiratory motion artifacts. A manual tracing application was developed to trace the ventricular surfaces in a true 4-D context and produced accurate independent standard for model construction and segmentation validation.
In the model construction stage, the 4-D AAMs were constructed using a custom designed automatic landmarking and texture mapping procedure with high efficiency.
In the computer segmentation stage, the 4-D AAMs were applied to segment the left and right ventricles of 25 normal and 25 TOF patient scans. The segmentation achieved accurate results measured by signed surface positioning errors. On normal hearts, the average signed errors were 0.3±2.3 mm for LV and 0.1±3.4 mm for RV. On TOF hearts with large shape variability, the errors were -1.5±3.2 mm for LV and -0.9±4.3 mm for RV. Other error metrics such as relative overlapping also indicated good segmentation accuracies.
In the computer-aided diagnosis stage, 100% normal/TOF classification was achieved using the novel 4-D ventricular function indices -- the shape modal indices. The longitudinal analysis performed on subjects with multiple annual scans showed that the normal subjects exhibited smaller variances of these 4-D indices than TOF patients, which demonstrated the potential of using them as disease status determinants. In addition, the quantitative 4-D indices provided more information about the dynamic properties of the heart and identified patient-specific features that were not sensed by human expert observers.
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König, Sabrina [Verfasser], and D. [Akademischer Betreuer] Wedlich. "Regulation des Transkriptionsfaktors Tcf-4 in der Gehirnentwicklung von Xenopus laevis / Sabrina König. Betreuer: D. Wedlich." Karlsruhe : KIT-Bibliothek, 2009. http://d-nb.info/1013696204/34.
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Al, Mazro'ey Mohamed Ahmed Salim. "Fluid characterisation using 4-D seismic amplitude and choherence anaylsis : application to Oseberg gas/oil field." Thesis, Imperial College London, 2003. http://hdl.handle.net/10044/1/8416.
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Якубец, В. И. "Синтез и химические превращения 2-S или (0) -замещенных тиено [2,3-d] пиримидин-(3Н)-4-онов." Diss. of Candidate of Chemical Sciences, Ужгород. гос. ун-т, Хим. ф-т, Каф. органической химии, 1988.
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SANTOS, Arthur Bernardo de Souza. "Cromóforos rígidos derivados de tiazol o [5, 4-d] tiazol: cristais líquidos e sais orgânicos fotocromáticos." Universidade Federal de Pernambuco, 2016. https://repositorio.ufpe.br/handle/123456789/17508.
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O estudo das propriedades de materiais orgânicos tem chamado atenção devido sua versatilidade estrutural e de composição que podem moldar suas propriedades físicas e químicas. Neste trabalho preparamos seis cromóforos rígidos contendo o heterociclo tiazolo[5,4-d]tiazol (Thz) como espaçador aromático, e grupos terminais piridínicos ou carboxílicos. Desta forma trabalhamos com duas linhas de pesquisa: foto-eletroquímica para os derivados piridínicos e síntese e caracterização de cristais líquidos (CLs). Investigamos as propriedades fotoquímicas e processos redox das bipiridinas X,X'-(tiazolo[5,4-d]tiazol-2,5- dil)bis(piridil) (X,X’ = 2,2’; 3,3’ ou 4,4’). Em solução, apresentaram propriedades acidocrômica via foto- e eletrodissociação de solventes clorados. A seguir, preparamos sais de trifluoracetato dos bipiridínio (viologens), que apresentaram propriedades fotocromáticas via transferência de elétron quando expostos à radiação UVB. Utilizamos os derivados carboxílicos como centros rígidos para a preparação de cristais líquidos. Escolhemos o grupo carboxilato como precursor sintético dos conectores orgânicos: éster, amida e 1,3,4-oxadiazol. Planejamos os cristais líquidos contendo tais conectores e cadeias alquílicas dodeciloxi (-OC12H25), obtendo materiais com estrutura geral: centro rígido + conectores + cadeias alcóxi. De acordo com a estrutura dos centros rígidos, preparamos treze mesógenos calamíticos (ácido tiazolo[5,4- d]tiazol-2,5-dicarboxílico), das quais seis apresentaram mesofases calamítica (comportamento esperados) e três apresentaram mesofases discóticas. O fotocromismo apresentado pelos sais de bipiridinas frente à radiação UVB nos permite sugerir aplicações como dosimetria desta radiação, presente na luz solar. As propriedades mesomórficas ainda estão em estudo. No entanto, conseguimos obter CL’s discóticos a temperatura ambiente e uma mesofase discótica nemática, bastante rara.
The study properties of organic materials has drawn attention due to its structural versatility and composition versatility, which can shape their physical and chemical properties. In this work, we prepared six rigid chromophores containing the heterocycle thiazolo[5,4-d] thiazole (Thz) as aromatic spacers, and pyridyl or carboxylic terminal groups. Hence, we have worked with two research lines: photo-electrochemistry for the pyridine derivatives and synthesis and characterization of liquid crystals (LCs). We investigated the photochemical properties and redox processes of the bipyridines X,X'-(thiazolo[5,4-d] thiazole-2,5-diyl)bis(pyridyl) (X,X' = 2,2 '; 3,3' or 4,4 '). In solution, these compounds showed acidochromic properties via photonand electrodissociantion of chlorinated solvents. Next, we prepare bipyridinium trifluoroacetate salts (viologens), which exhibited photochromic properties through electron transfer when exposed to UVB radiation. We used the carboxylic derivatives as rigid centers for the preparation of liquid crystals. We chose the carboxylate group as a synthetic precursor of organic connectors: esther, amide, and 1,3,5-oxadiazole. We plannned the liquid crystal containing these connectors and the alkoxy chains dodecyloxy (-OC12H25), obtaining materials with general structure: rigid center + connectors + alkoxy chains. According to the rigid center structure, we obtained thirteen calamitic (acid thiazolo [5,4-d] thiazole-2,5-dicarboxylic acid), six of which had mesophases calamítica (expected behavior) and three had discóticas mesophases. The photochromic presented by bipyridinium salts when exposed of UVB radiation allows suggest applications such as dosimetry of sunlight radiation. The mesomorphic properties are still under study. However, we obtained room temperatures discóticos LCs, as well as a nematic discótica mesophase which are quite rare.
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Roski, James Peter. "The synthesis and reactions of 1,6-anhydro-2,3-dideoxy-?-D- glycero-hex-2-enopyran-4-ulose /." The Ohio State University, 1991. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487759055158956.
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By, Kolbot. "PH-sensitive lipids and synthesis of a C(4)-C(9) eleutheside template from D-glucal /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2003. http://uclibs.org/PID/11984.
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