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Assaf, Joumana. "Étude théorique des molécules LuBr et LuI par les méthodes ab-initio." Thesis, Lille 1, 2014. http://www.theses.fr/2014LIL10070.
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Le travail de recherche présenté concerne l'étude théorique des molécules LuBr et LuI qui sont considérées comme des molécules d'intérêt astrophysique. Les calculs ont été effectués en utilisant les méthodes de chimie quantique usuelles pour ce type de molécules comme les méthodes Hartree-Fock Self-Consistent Field (SCF) , Complete Active Space Self-Consistent Field (CAS-SCF) et les méthodes d'interaction de configurations multi-référence (MRCI) avec la correction de Davidson. Pour cela, la chaîne de programmes MOLPRO a été utilisée. Les courbes d'énergie potentielle ont été déterminées pour un grand nombre d'états électroniques dans un premier temps sans considérer l'interaction spin-orbite puis en l'incluant. Les constantes spectroscopiques (position d'équilibre (Re), l'énergie d'excitation (Te) et la fréquence harmonique (we) ont été déduites et comparées aux rares résultats expérimentaux disponibles dans la littérature pour ces deux moléculesThis work concerns the theoretical study of the electronic structure of two molecules of astrophysical interest, LuBr and LuI. Ab-initio methods have been used as Self-Consistent Field (SCF) method, Complete Active Space Self-Consistent Field (CAS-SCF) method and MRCI calculations including Davidson correction. Calculations have been performed through MOLPRO. Potential energy curves have been determined for numerous electronic states first without the spin-orbit coupling and afterwards with this interaction. Spectroscopic constants as equilibrium position (Re), excitation energy (Te) and harmonic frequency (we) have been deduced and compared with available experimental data for these two molecules
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Faini, Marie Annette. "Transcriptional Control during Quorum Sensing by LuxR and LuxR Homologues." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/31994.
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Quorum sensing is a mechanism used by many proteobacteria to regulate expression of target genes in a population-dependent manner. The quorum sensing system of Vibrio fischeri activates the luminescence (lux) operon when the autoinducer signaling molecule (N-3-oxohexanoyl homoserine lactone) is recognized and bound by the activator protein LuxR. LuxR subsequently binds to the lux box centered at à 42.5 bp upstream of the transcription initiation site and activates transcription from the lux operon promoter, resulting in the emission of light at high cell densities. LuxR consists of 250 amino acids arranged into an N-terminal (regulatory) domain and a C-terminal (activation) domain, and is thought to function as an ambidextrous activator capable of making multiple contacts with the alpha and sigma subunits of RNA polymerase (RNAP). Published work describing the results of alanine scanning mutagenesis performed on the C-terminal domain of LuxR (residues 190-250) has identified residues (K198, W201 and I206) that appear to play a role in positive control of transcription initiation. Additional mutagenesis of residues 180-189 has been undertaken via a three-primer or four-primer PCR-based method in this study. Variants of LuxR were screened for their ability to activate luciferase production and to repress transcription from an artificial promoter, and production of full-length LuxR was measured, in an attempt to identify additional positive control variants. No additional positive control variants were found in this study. Work has also been undertaken to identify intergenic suppressors between positive control variants of LuxR and the RNAP alpha subunit, RpoA. Starting with a recombinant Escherichia coli strain encoding the lux operon and LuxR variant I206E, a random chemical mutagenesis was performed on a vector encoding RpoA. Following transformation of the mutated plasmids encoding RpoA, high throughput luminescence assays were used to identify isolates with phenotypes brighter than the control. Isolation of an intergenic suppressor will confirm the existence of protein-protein interactions between LuxR and RpoA within the transcription initiation complex. The ability of other LuxR family members to establish productive protein-protein interactions with RNAP necessary for transcription initiation was also examined. LuxR homologues EsaR of Pantoea stewarti ssp. stewartii, a repressor of known function, and ExpR of Erwinia carotovora subsp. carotovora were also analyzed for their ability to activate the lux operon, as well as to repress transcription from an artificial promoter containing the lux box.Master of Science
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Martínez, M. Cristián, C. Christián Méndez, and P. Esteban Díaz. "Bio-Lube lubricantes ecológicos." Tesis, Universidad de Chile, 2004. http://www.repositorio.uchile.cl/handle/2250/113699.
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Tesis para optar al grado de Magíster en Administración1.1 Oportunidad del Negocio El fuerte crecimiento del rubro industrial forestal en la última década (cerca del 30%), provocado en parte por un aumento en las exportaciones de madera, ha llevado a las empresas a realizar fuertes inversiones en automatización y mecanización de los procesos productivos, para conseguir ser más eficientes y por lo tanto competitivos con el resto del mundo. Este crecimiento y las inversiones realizadas han traído consigo serios problemas de contaminación ambiental, lo cual dentro de las políticas de gobierno y las exigencias de los mercados de destino de los productos madereros, han provocado que las empresas introduzcan fuertes cambios para solucionar los problemas ambientales modificando o sustituyendo aditivos o productos por otros que permitan que los procesos productivos sean más limpios. Entre los problemas que actualmente enfrentan todas las empresas del rubro aserraderos y plantas de remanufacturas, existe el de los derrames producidos por el uso de aceites derivados de hidrocarburos en la lubricación de equipos y cadenas. Para solucionar este problema es que nace como una necesidad Bio-Lube Ltda., empresa fabricante y comercializadora de aceites de origen vegetal para ser usados como lubricantes de cadena y otras aplicaciones de procesos productivos forestales, cuyo producto Bio-Chain WR, soluciona el problema de contaminación, al ser un producto 100% biodegradable y con un precio producto-rendimiento de menor valor que los biodegrables que se ofrecen actualmente en el mercado y muy competitivo con respecto a los derivados de hidrocarburos que se utilizan aún. 1.2 Modelo de Negocio Nuestra empresa ofrecerá el producto Bio-Chain WR, el cual ha sido formulado sobre la base de aceites vegetales (aceite de canola) y aditivos biodegradables, cuya composición se mantiene en reserva de sus dueños. El producto se comercializará en formato de tambores de 208 lts., mismo formato que utilizan las compañías competidoras. El precio de venta del producto será de $2100 + IVA, el cual es similar a los lubricantes base hidrocarburos y muy por debajo de las alternativas biodegradables (30 a 40% menos). El potencial de mercado para el producto Bio-Chain WR es de 280 tambores/mes considerando sólo las regiones VII, VIII y IX, que es donde se concentra el 85% del mercado. Bio-Lube Ltda., espera conseguir como objetivos de venta alcanzar el 5% (14 tambores/mes) del mercado en su primer año (a partir del segundo semestre), para luego aumentar en un 15% (42 tambores/mes) en el segundo año y para lograr desde el tercer al quinto años una participación del 25% (70 tambores/mes). La estrategia de comercialización contempla una etapa de introducción del producto al mercado, para lo cual se espera visitar en una primera etapa a los clientes de mayor nivel de consumo ofreciendo una prueba del producto sin costo, si esta no cumple las exigencias de calidad y rendimiento del cliente. Se estima que el tiempo para introducir el producto al mercado será de 3 a 4 meses. Adicionalmente, se realizará una campaña de marketing para fortalecer las cualidades del producto y la empresa. La estrategia de marketing se desarrollará en dos ámbitos: Imagen corporativa y de la marca; para lo cual se cuenta con un programa de actividades y presupuesto por año. En una primera etapa la estrategia será de marketing directo, fuerte en relaciones interpersonales, hacia las empresas. Aquí los ejecutivos de ventas se dirigen hacia los clientes. En la segunda etapa se realizará un marketing más indirecto y masivo con la utilización de medios tradicionales de publicidad. Lubricantes Ecológicos Bio-Lube Ltda. Parque Industrial S/N, Lota, VIII Región www.biolube.cl 3 1.3 Equipo y modelo organizacional El equipo ejecutivo de Bio-Lube Ltda. está compuesto por el Sr. Esteban Díaz, Gerente General, Ingeniero Comercial, con una gran red de contactos en la zona y con 10 años de experiencia en el sector financiero; Sr. Christian Méndez, Gerente Técnico y apoyo ventas, Ingeniero Civil Químico, con 10 años de experiencia en el sector forestal, desarrollando su carrera en producción, ingeniería y proyectos en empresas del rubro. Sr. Cristian Martínez, Gerente Comercial y apoyo ventas, Ing. Civil Industrial, con 8 años de experiencia en comercialización de lubricantes y asesorías en lubricación para el sector forestal e industrial. Adicionalmente, se contempla la contratación de dos personas para el área producción, bodega y despachos. 1.4 Proyecciones Financieras El valor de la empresa Bio-Lube Ltda. es de $140.994.352 millones y ha sido calculada en base a los flujos de caja de los primeros 5 años. La tasa de descuento utilizada para la evaluación es de un 30%, considerando una tasa por capitales de riesgo. La tasa interna de retorno es de un 88.64% y la inversión se recupera en los primeros 3 años. 1.5 Propuesta a los Inversionistas A continuación, se desglosa el capital requerido para la realización del proyecto Bio-Lube, el cual está compuesto por activo fijo y capital de trabajo.
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Miller, Thomas C. (Thomas Charles). "Characterization of lube oil derived diesel engine particulate emission rate vs. lube oil consumption." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/28171.
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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1996, and Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1996.Includes bibliographical references (p. 103-104).
by Thomas C. Miller.
M.S.
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Bezerra, Diogo Henrique Duarte. "Luar-X: extens?o e generaliza??o do sistema de processamento de modelos luar." PROGRAMA DE P?S-GRADUA??O EM ENGENHARIA EL?TRICA E DE COMPUTA??O, 2016. https://repositorio.ufrn.br/jspui/handle/123456789/21944.
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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES)
O sistema de processamento de modelos Luar, utilizado na autoria de documentos NCL, possui conceitos de desenvolvimento baseados no re?so de descri??es por meio de modelos de documentos. Esses conceitos de desenvolvimento podem ser utilizados na autoria de outros documentos baseados em XML por meio da an?lise, adequa??o, projeto e cria??o de uma nova infraestrutura de re?so baseada no sistema Luar. Esta tese apresenta o sistema de processamento de modelos Luar-X, uma generaliza??o e extens?o do sistema de modelos Luar. O Luar-X mant?m os conceitos de desenvolvimento do sistema Luar e modifica, adequa e estende a arquitetura do sistema Luar para permitir o desenvolvimento com linguagens baseadas em XML. Os estudos de caso com as linguagens HTML, SVG e NCL mostram a viabilidade dessa nova infraestrutura de re?so que torna o desenvolvimento de aplica??es e a descri??o de documentos XML ?gil.
The Luar template processing system used in authoring NCL documents, has development concepts based on reuse of descriptions through document templates. These development concepts can be used in the authorship of other XML-based documents through the analysis, adequacy, design and creation of a new reuse infrastructure based on Luar system. This view shows the processing system of models Luar-X, a generalization and extension Luar model system. The Luar-X keeps the concepts of development of Luar system and he changes, adapts and extends the Luar system architecture to enable development with XML-based languages. The case studies with HTML, SVG and NCL show the feasibility of this new reuse infrastructure, which makes application development and description of agile XML documents.
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Kalonji, M. T. Zezeze. "Sémiotique de la lexicographie bilingue en Afrique francophone : le cas Français-Ciluba : (problématique, analyse des dictionnaires et préalables pour un modèle minimal fonctionnalisé)." Paris 13, 1987. http://www.theses.fr/1987PA131022.
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Ce travail consiste a: - poser la problematique generale de la lexicographie bilingue en afrique francophone, a travers le cas francais-ciluba. Par la, c'est le dictionnaire qui est "re-situe" dans ses origines, ses multiples sous-entendus ideologiques, et ses presupposes sociologiques: c'est une sorte d'exploration des fondements du discours lexicographique en milieu africain franco-lubaphone. - analyser l'ensemble des dictionnaires et lexiques bilingues existants aussi bien dans leur conception que dans leur presentation macro- et microstructu- relle, afin d'en determiner, par le jeu de comparaison avec les dictionnaires monolingues, la fonctionnalite linguistique et culturelle, mais surtout pour nous approprier, en consequence, les techniques diverses de la lexicographie. - presenter une approche morpho-lexicale du "mot" en "ciluba", unite graphique pour le texte lexicographique, mais dont les aspects phonologiques, morphologi- ques et morpho-semantiques doivent etre degages aux fins d'une analyse lexico- - semantique efficace du lexique luba ou de la traduction interlinguistique. - elaborer, en conclusion, les prealables theoriques pour un modele de diction- naire bilingue fonctionnalise. Ces prealables etant inspires de l'ensemble de la problematique et de l'analyse des dictionnaires bilingues, ils fournissent les elements theoriques pour la conception et l'elaboration de dictionnaires en milieu francophone d'afrique. Ces prealables sont suivis en illustration d'un traitement lexicographique d'un corpus de nomenclature. De cette maniere, c'est non seulement une etude intrinsequement linguistique qui est menee, mais une approche multidimensionnelle du fait lexicographique francais-luba et vice-versa. Il est nettement apparu que pour etre efficiente, une etude qui vise non seulement la comprehension interne du fait lexicographique bilingue en afrique, mais aussi la composition de nouveaux dictionnaires, devait s'appuyer sur des donnees objectives de la sociologie des locuteurs franco-lubaphones, leur typologie ainsi que leurs besoins approximatifsThe aim of this study is: - to set up a general "problematique" of the bilingual lexicography in franco- phone africa, through the french-ciluba case study. The dictionary is so re- placed in its origins, its various ideological understatements, its sociolo- gical preables: which means to explore the fundamentals of the lexicographic discourse in an african franco-lubaphone context. - to analyse the whole range of the existing bilingual dictionaries and lexi- cons , their elaboration as well as their macro- and microstructural shapa, in order to define their linguistic and cultural functionality in comparison with the monolingual dictionaries, and above all to get acquainted with the various lexicographic techniques. - to display a morpho-lexical analysis of the "word" in ciluba language, a graphic unit for the lexicographic text, but the phonological, morphological and morpho-semantical aspects of which have to be isolated for an efficient lexical and semantical analysis of the luba lexicon or the interlinguistic translation. - to conclude in, with the theorical preables for a functionalized model of the bilingual dictionary. As these preables are based on the "problemati- que" and the study the bilingual dictionaries, they provide for the theori- cal elements for the building of dictionaries in the francophone african context. Following the preables is, as an illustration, a lexicographic pro- cessing of a sample of the "nomenclature"
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Kalonji, M. T. Zezeze. "Sémiotique de la lexicographie bilingue en Afrique francophone le cas français-ciluba : problématique, analyse des dictionnaires et préalables pour un modèle minimal fonctionnalisé /." Lille 3 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37606354k.
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Gesemann, Sebastian [Verfasser], Gert [Akademischer Betreuer] Lube, Gert [Gutachter] Lube, and Marcus [Gutachter] Baum. "Optimizations of Optical Flow Measurement Systems / Sebastian Gesemann ; Gutachter: Gert Lube, Marcus Baum ; Betreuer: Gert Lube." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2018. http://d-nb.info/1169912346/34.
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Ramzan, Zulfikar Amin 1975. "A study of Luby-Rackoff ciphers." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/86580.
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Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2001.Includes bibliographical references (p. 188-200).
by Zulfikar Amin Ramzan.
Ph.D.
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Collins, Cynthia Hollie Parker Carl Stevens. "Directed evolution of the transcriptional activator LuxR /." Diss., Pasadena, Calif. : Caltech, 2006. http://resolver.caltech.edu/CaltechETD:etd-12272005-160649.
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Petit, Pierre. "Rites familiaux, rites royaux: étude du système cérémoniel des Luba du Shaba, Zaïre." Doctoral thesis, Universite Libre de Bruxelles, 1993. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/212757.
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Kramer, Stephan Christoph [Verfasser], Gert [Akademischer Betreuer] Lube, and Reiner [Akademischer Betreuer] Kree. "CUDA-based Scientific Computing : Tools and Selected Applications / Stephan Christoph Kramer. Gutachter: Gert Lube ; Reiner Kree. Betreuer: Gert Lube." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2013. http://d-nb.info/1044074523/34.
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Löwe, Johannes [Verfasser], Gert [Akademischer Betreuer] Lube, and Gerlind [Akademischer Betreuer] Plonka-Hoch. "Eine Finite-Elemente-Methode für nicht-isotherme inkompressible Strömungsprobleme / Johannes Löwe. Gutachter: Gert Lube ; Gerlind Plonka-Hoch. Betreuer: Gert Lube." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2011. http://d-nb.info/1043514961/34.
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Arndt, Daniel [Verfasser], Gert [Akademischer Betreuer] Lube, Andreas [Akademischer Betreuer] Dillmann, and Guido [Akademischer Betreuer] Kanschat. "Stabilized Finite Element Methods for Coupled Incompressible Flow Problems / Daniel Arndt. Betreuer: Gert Lube. Gutachter: Gert Lube ; Andreas Dillmann ; Guido Kanschat." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2016. http://d-nb.info/1081820411/34.
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Heister, Timo [Verfasser], Gert [Akademischer Betreuer] Lube, and Robert [Akademischer Betreuer] Schaback. "A Massively Parallel Finite Element Framework with Application to Incompressible Flows / Timo Heister. Gutachter: Gert Lube ; Robert Schaback. Betreuer: Gert Lube." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2011. http://d-nb.info/1042970157/34.
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Wacker, Benjamin [Verfasser], Gert [Akademischer Betreuer] Lube, and Thorsten [Akademischer Betreuer] Hohage. "Stabilisierte Lagrange Finite-Elemente im Elektromagnetismus und in der inkompressiblen Magnetohydrodynamik / Benjamin Wacker. Betreuer: Gert Lube. Gutachter: Gert Lube ; Thorsten Hohage." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2015. http://d-nb.info/1078420165/34.
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Kalonji, M. T. Zezeze Lerat Pierre. "La lexicographie bilingue en Afrique francophone : l'exemple français-cilubà /." Paris : Éd. l'Harmattan, 1993. http://catalogue.bnf.fr/ark:/12148/cb35624697b.
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Dallmann, Helene [Verfasser], Gert [Akademischer Betreuer] Lube, and Malte [Akademischer Betreuer] Braack. "Finite Element Methods with Local Projection Stabilization for Thermally Coupled Incompressible Flow / Helene Dallmann. Gutachter: Gert Lube ; Malte Braack. Betreuer: Gert Lube." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2015. http://d-nb.info/1076673600/34.
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Merklein, Johannes [Verfasser], Gert [Akademischer Betreuer] Lube, Oleg [Akademischer Betreuer] Panferov, and Wolfram [Akademischer Betreuer] Schmidt. "Modellierung turbulenter Strömungen mit Anwendungsfällen in der Bioklimatologie und Astrophysik / Johannes Merklein. Gutachter: Gert Lube ; Oleg Panferov ; Wolfram Schmidt. Betreuer: Gert Lube." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2014. http://d-nb.info/1047237059/34.
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Luhr, David [Verfasser], and Ewald [Akademischer Betreuer] Terhart. "Unterrichtskompetenz erfassen und entwickeln / David Luhr ; Betreuer: Ewald Terhart." Münster : Universitäts- und Landesbibliothek Münster, 2016. http://d-nb.info/1141178427/34.
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Brameyer, Sophie. "Cell-cell communication via LuxR solos in Photorhabdus species." Diss., Ludwig-Maximilians-Universität München, 2015. http://nbn-resolving.de/urn:nbn:de:bvb:19-181139.
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Bacteria constantly need to monitor their environment and adapt the bacterial group-coordinated behaviour to changing habitats like nutrition alterations or host variations. Commonly cell-cell communication via acyl homoserine lactones (AHLs)is used to synchronise the behaviour of a bacterial population dependent on cell size. This process is referred to as quorum sensing (QS) and predominantly occurs in
Gram-negative bacteria. The typical QS system consists of a LuxI-synthase that synthesises AHLs, and a LuxR-type receptor, which then responds to these AHLs. Upon AHL-binding, the LuxR-type receptor regulates the expression of different target genes and thus influences several processes, like biofilm formation, virulence, antibiotic production or cell-cell interaction. Interestingly, many proteobacteria
possess additional LuxR homologs, but lack a cognate LuxI-type synthase. Those LuxR-type receptors are referred to as LuxR orphans or LuxR solos and can expand the regulatory QS network. Photorhabdus species are insect pathogenic bacteria,
living in symbiosis with entomopathogenic nematodes. They all possess an
exceptionally high number of LuxR solos, but lack LuxI homologs and therefore do
not produce AHLs. The function of these LuxR solos, their role in cell-cell
communication and the identification of their cognate signalling molecules in
Photorhabdus species is the main focus of this work.
In this thesis a novel signalling molecule used for QS could be identified for the
first time in P. luminescens. This novel QS molecule is an α-pyrone named
photopyrone (PPY) and produced endogenously by the photopyrone synthase (PpyS).
The PPYs are specifically recognized by the LuxR solo regulator PluR, which then
activates expression of the pcf (Photorhabdus clumping factor) operon leading to cell
clumping of P. luminescens cells. Moreover, the PpyS/PluR quorum sensing system
and its induced cell clumping contribute to the overall toxicity of P. luminescens.
Furthermore, a second novel signalling molecule sensed by a LuxR solo of
Photorhabdus species could be identified besides PPYs. The insect and human
pathogenic bacteria P. asymbiotica lacks a PpyS homolog as well as a LuxI homolog,
but harbours a pcf operon and a homologue to PluR, which is named PauR. The
signalling molecule sensed by the LuxR-type receptor PauR could be identified,
which is neither an AHL nor a PPY. PauR recognises a 2,5-dialkylresorcinol (DAR)
produced by the DarABC pathway. Upon binding of the cognate signalling molecule,
Summary
XII
PauR activates expression of the pcf operon. This also leads to cell clumping in
P. asymbiotica. Furthermore, the DarABC/PauR QS system also contributes to the
overall pathogenicity of P. asymbiotica against Galleria mellonella insect larvae.
A bioinformatics approach revealed a high number of LuxR solos present in
P. temperata and P. asymbiotica like in P. luminescens. Thereby, several conserved
motives of amino acids could be identified, which are potentially important for signalbinding
and -specificity. Variations in these amino acid motifs are assumed to reflect
the overall variety of signals that can be sensed by LuxR solos.
Furthermore, the specificity of the two LuxR solos PluR and PauR towards their
cognate signalling molecules, PPYs and DARs, respectively, was analysed. Thereby,
it could be shown that the previously identified conserved amino acid motives in the
signal-binding domain (SBD), the TYDQCS-motif of PluR and the TYDQYI-motif of
PauR, are essential but not sufficient for ligand-binding.
Similar as for AHLs, it was unclear how the signalling molecules PPYs and DARs
can cross the bacterial cell membrane. In the last part of this thesis the import
mechanism for the Photorhabdus-specific signalling compounds PPYs and DARs
were identified. Initial evidence could be provided that the membrane-integrated
transporter FadL is mainly involved in the import of these hydrophobic compounds,
and that they are not transported via simple diffusion across the cell membrane, which
is assumed for AHLs.
In conclusion, the data that is compiled presents two LuxR solos of Photorhabdus
species adapted to sense and respond to novel non-AHL signalling molecules used for
QS. Therefore, this thesis reveals that cell-cell communication via LuxR-type
receptors goes far beyond AHL-signalling in nature.
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Cecchini, Giselle Molon. "Lucr?cia Borgia : drama no oceano de Victor Hugo." Pontif?cia Universidade Cat?lica do Rio Grande do Sul, 2009. http://tede2.pucrs.br/tede2/handle/tede/1924.
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Previous issue date: 2009-09-30Esta disserta??o apresenta um estudo descritivo e cr?tico do drama hist?rico Lucr?cia Borgia, de Victor Hugo, ? luz de teorias desenvolvidas por Anne Ubersfeld, Patrice Pavis, Constantin Stanislavski, Grotowski, Pierre Albouy, Jurij Alschitz. Escrita sob a perspectiva do ator, a disserta??o objetiva evidenciar que, a partir da leitura do texto dram?tico, com o conhecimento dos signos c?nicos, os temas presentes na obra emergem, produzindo novos sentidos. Eles constituem as potencialidades contidas no texto. A obra de Victor Hugo ? compreendida pelo escritor como um todo indivis?vel. Por isso, a pesquisa abrange a hist?ria de vida e a obra de Hugo, fatores fundamentais para se realizar o cotejo com Lucr?cia Borgia e para efetivar a tradu??o do drama hist?rico, escrito originalmente em l?ngua francesa.
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Reuter, Lea Vanessa [Verfasser], Birgit [Akademischer Betreuer] Luber, and Heinz Karl [Akademischer Betreuer] Höfler. "Prognostische Bedeutung des EGF-Rezeptor-Signalweges und Tumor-infiltrierender Lymphozyten beim Magenkarzinom / Lea Vanessa Reuter. Gutachter: Birgit Luber ; Heinz Karl Höfler. Betreuer: Birgit Luber." München : Universitätsbibliothek der TU München, 2014. http://d-nb.info/1055040021/34.
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Williams, Joshua W. "Multi-tiered Regulation of luxR Provides Precise Timing and Maintenance of the Quorum Sensing Response of Vibrio fischeri." Diss., Virginia Tech, 2009. http://hdl.handle.net/10919/38580.
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The quorum-sensing response of Vibrio fischeri involves a complex network of genes (encoding regulatory proteins as well as sRNAs), that govern host-association and production of bioluminescence. A key regulator of this system is LuxR, which is the transcriptional activator of the lux operon as well as several other genes in. LuxR also autoregulates its own transcription, which we have shown causes bistability and hysteresis in the quorum-sensing response. This behavior allows the system to maintain a stable and robust response in the face of environmental fluctuation or decreases in external autoinducer concentration caused by other sources. There are many factors that are known to regulate luxR expression, including the ArcA redox-responsive regulator, the cAMP-CRP secondary metabolism regulator, and components of the quorum-sensing pathway like LitR. Because of this, LuxR levels are critical in both the timing of quorum-sensing induction, as well as the maintenance of the response over time. This makes it a potential target for multiple levels of regulation in response to factors such as environmental and metabolic conditions, as well as other components of the quorum-sensing network.
Another important global regulatory protein in V. fischeri (and most other species of Gram-negative proteobacteria) is the post-transcriptional regulator CsrA. CsrA controls processes involved in carbon storage and utilization, as well as the transition from exponential to stationary phase growth. We have demonstrated that CsrA is regulated by two sRNAs (CsrB1 and CsrB2) in V. fischeri. Because CsrA regulates changes in cell behavior and is an important metabolic regulator, there is a good possibility that it has some interactions with the quorum-sensing regulon, whose endproduct, bioluminescence, creates a large metabolic demand from the cell.
In an effort to determine at which point in the quorum-sensing regulatory network CsrA regulation is important, epistasis experiments were designed using factorial design, which is a subset of statistical analysis of variance (ANOVA). This method was used to generate a high degree of confidence in the data, so that even minor interactions in the regulatory networks could be established. By altering the levels of CsrA expression in various mutant strains of V. fischeri, we have demonstrated that CsrA acts by an unknown mechanism to increase the transcription of luxR when the quorum-sensing regulator LitR is absent. Our results also demonstrated that CsrA mediates this effect through repression of ArcA activity, which is known to act directly on the luxR and luxI intergenic region as a repressor. This indicates that CsrA may bypass the upstream parts of the quorum-sensing regulatory cascade that lead to litR activation, so that LitR and LuxR may be regulated differently in response to certain conditions.
This work has shown that the interactions between global regulons can coordinately control the amount of quorum-sensing induction by affecting the level of LuxR in the cell. The balance of these regulatory networks allows the cell to tightly regulate the quorum-sensing response. Thus, LuxR serves as a critical regulatory hub in the cell, at which multiple signals can be integrated in order to generate the appropriate cellular response.Ph. D.
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Kamba, Tchitala Nyota. "Théâtre rituel, le veuvage de la femme luba et ses mystères." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0014/NQ38811.pdf.
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Marcelino, Neto Moisés A. "Caracterização de propriedades termofísicas de misturas de óleos lubrificantes e fluídos refrigerantes naturais." Florianópolis, SC, 2006. http://repositorio.ufsc.br/xmlui/handle/123456789/88659.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia MecânicaMade available in DSpace on 2012-10-22T12:07:29Z (GMT). No. of bitstreams: 1 233812.pdf: 1997158 bytes, checksum: 7d4b9c362eb494a08c6ac300a2f65929 (MD5)
A eliminação do uso dos refrigerantes halogenados, em função dos prejuízos que causam à camada de ozônio e de sua contribuição para o aquecimento global, deu início a uma nova era na refrigeração, na qual o desempenho ambiental dos fluidos refrigerantes passou a ter importância fundamental.
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Sellick, Katelyn. "A Possible luxR Solo Type Regulator of an Antibiotic-Like Compound from the Soil Bacterium Rhodococcus." Digital Commons @ East Tennessee State University, 2019. https://dc.etsu.edu/etd/3649.
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Rhodococcus, a species of bacteria commonly found in the soil, is an under-explored producer of small bioactive compounds including siderophores, pigments and antibiotics. MTM3W5.2 is a strain of Rhodococcus that was previously discovered to produce an antibiotic-like compound that has inhibitory effects on other Rhodococcus strains, including the veterinary pathogen, R. equi. The biosynthetic gene cluster responsible for production of the antibiotic has been identified, and a small gene, BTZ20_3964 at the start of the operon is believed to be a luxR solo regulator of the gene cluster. The goal of this project was to determine this gene’s status as a regulator for the gene cluster. Merodiploids were constructed using the deletion construct, pEX18Km3964AD to obtain a double crossover recombination event to replace the functional gene with the deletion construct. However, evidence indicates that an illegitimate recombination event occurred to produce a merodiploid strain.
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Schroeder, Philipp W. [Verfasser], Gert [Akademischer Betreuer] Lube, Gert [Gutachter] Lube, Andreas [Gutachter] Dillmann, and Leo G. [Gutachter] Rebholz. "Robustness of High-Order Divergence-Free Finite Element Methods for Incompressible Computational Fluid Dynamics / Philipp W. Schroeder ; Gutachter: Gert, Lube; Andreas, Dillmann; Leo G., Rebholz ; Betreuer: Gert, Lube." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2019. http://d-nb.info/1180026489/34.
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Zwingenberger, Gwen [Verfasser], Birgit [Akademischer Betreuer] Luber, Birgit [Gutachter] Luber, and Michael [Gutachter] Schemann. "Molecular and phenotypical characterization of gastric cancer cell lines and validation of potential resistance factors to trastuzumab therapy / Gwen Zwingenberger ; Gutachter: Birgit Luber, Michael Schemann ; Betreuer: Birgit Luber." München : Universitätsbibliothek der TU München, 2019. http://d-nb.info/118625663X/34.
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Bertarelli, Lorenza. "Analisi delle prestazioni della piattaforma semantica smart-m3 mediante il benchmark lubm." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/9263/.
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Il software Smart-M3, ereditato dal progetto europeo SOFIA, conclusosi nel 2011, permette di creare una piattaforma d'interoperabilità indipendente dal tipo di dispositivi e dal loro dominio di utilizzo e che miri a fornire un Web Semantico di informazioni condivisibili fra entità software e dispositivi, creando ambienti intelligenti e collegamenti tra il mondo reale e virtuale. Questo è un campo in continua ascesa grazie al progressivo e regolare sviluppo sia della tecnologia, nell'ambito della miniaturizzazione dei dispositivi, che delle potenzialità dei sistemi embedded. Questi sistemi permettono, tramite l'uso sempre maggiore di sensori e attuatori, l'elaborazione delle informazioni provenienti dall’esterno.
È evidente, come un software di tale portata, possa avere una molteplicità di applicazioni, alcune delle quali, nell’ambito della Biomedica, può esprimersi nella telemedicina e nei sistemi e-Heath. Per e-Health si intende infatti l’utilizzo di strumenti basati sulle tecnologie dell'informazione e della comunicazione, per sostenere e promuovere la prevenzione, la diagnosi, il trattamento e il monitoraggio delle malattie e la gestione della salute e dello stile di vita.
Obiettivo di questa tesi è fornire un set di dati che mirino ad ottimizzare e perfezionare i criteri nella scelta applicativa di tali strutture. Misureremo prestazioni e capacità di svolgere più o meno velocemente, precisamente ed accuratamente, un particolare compito per cui tale software è stato progettato. Ciò si costruisce sull’esecuzione di un benchmark su diverse implementazioni di Smart-M3 ed in particolare sul componente centrale denominato SIB (Semantic Information Broker).
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Fujita, Humberto [UNESP]. "Retificação da alumina com rebolo diamantado usando diferentes métodos de lubri-refrigeração." Universidade Estadual Paulista (UNESP), 2007. http://hdl.handle.net/11449/88465.
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fujita_h_me_bauru.pdf: 3757663 bytes, checksum: 66acc24c6f3d11d42e726d1b452899b3 (MD5)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O sucesso da cerâmica estrutural na maioria das aplicações depende não somente das propriedades do material e do projeto da peça, mas também da qualidade do produto usinado. Um dos fatores citados como obstáculo à ampla utilização das cerâmicas é a falta de confiabilidade dos componentes de cerâmica, em função da grande dispersão dos valores de resistência mecânica provocada por defeitos que podem ter origem no processo de retificação. A retificação de cerâmica, assim como na indústria de processamento metal-mecânica, é realizada normalmente com abundância de fluidos de corte. A utilização destes fluidos refrigerantes resulta em problemas ecológicos, fisiológicos e econômicos. Desde a última década, a opinião pública, o mercado, as leis e regulamentos têm pressionado as indústrias para considerar os riscos ambientais na manufatura. Com o propósito de avaliar alternativas ao método convencional de lubri-refrigeração, foi estudada a viabilidade da técnica de refrigeração otimizada, onde o fluido de corte é aplicado à mesma velocidade periférica do rebolo, penetrando na região de corte com menos turbulência. Também foi analisada a técnica da Mínima Quantidade de Lubrificação (MQL), na qual o grande volume de fluido de corte é substituído por um jato de ar contendo uma quantidade ínfima de lubrificante. Os métodos foram comparados através da análise de desempenho durante o processo de retificação (forças de corte, emissão acústica, energia de retificação) e pela caracterização dos corpos de prova (rugosidade, danos subsuperficiais) e do rebolo (relação G). A profundidade de corte e o efeito do spark-out também formaram parte do escopo deste trabalho. Os resultados obtidos mostraram que a profundidade de corte exerce grande influência durante o processo...
The success of structural ceramics in most applications depends not only on the materials properties and component design, but also the quality of machined products. One factor usually mentioned as a barrier to the wide use of ceramics is the lack of reliability of ceramic components, because the variability on the mechanical strength caused by defects that can be impaired in the grinding process. The grinding of ceramics, as much as with steel grinding is performed generally with excess of cutting fluids (coolants). The use of coolants results in serious ecological, physiological and economic issues. Since last decade the public opinion, the market, the laws and regulations have pushed the industries to consider the environmental risks in the manufacturing process. Then, in order to evaluate alternatives to the conventional method of cooling and lubrication, it was studied the viability of the optimized technique, where the cutting fluid is applied to the same peripherical speed of the wheel, penetrating in the cutting zone with less turbulence. Also, it was verified the technique of Minimum Quantity of Fluid (MQF), where a large amount of cutting fluid is replaced by an air compressed flow containing a small quantity of lubricant. The methods were compared through performance analysis during the grinding process (cutting forces, acoustic emission and specific grinding energy) and by characterization of specimens (roughness, subsurface damage) and wheel (G ratio). The depth of cut and the effect of spark-out were part of the scope of this work too. The results obtained showed that the depth of cut has great influence during the process and in the characterization of ceramics, while spark-out does not seem to be so significant. Another conclusion is that MQF is not viable in ceramics grinding with the working conditions proposed. The results obtained... (Complete abstract, click electronic access below)
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Poulter, Simon. "The LuxR-family quorum sensing transcriptional regulator CarR in Erwinia and Serratia." Thesis, University of Cambridge, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.609398.
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Fujita, Humberto. "Retificação da alumina com rebolo diamantado usando diferentes métodos de lubri-refrigeração /." Bauru : [s.l.], 2007. http://hdl.handle.net/11449/88465.
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Orientador: Eduardo Carlos BianchiBanca: Jaime Gilberto Duduch
Banca: Luiz Eduardo de Angelo Sanchez
O Programa de Pós-Graduação em Ciência e Tecnologia de Materiais, PosMat, tem caráter institucional e integra as atividades de pesquisa em materiais de diversos campi da Unesp
Resumo: O sucesso da cerâmica estrutural na maioria das aplicações depende não somente das propriedades do material e do projeto da peça, mas também da qualidade do produto usinado. Um dos fatores citados como obstáculo à ampla utilização das cerâmicas é a falta de confiabilidade dos componentes de cerâmica, em função da grande dispersão dos valores de resistência mecânica provocada por defeitos que podem ter origem no processo de retificação. A retificação de cerâmica, assim como na indústria de processamento metal-mecânica, é realizada normalmente com abundância de fluidos de corte. A utilização destes fluidos refrigerantes resulta em problemas ecológicos, fisiológicos e econômicos. Desde a última década, a opinião pública, o mercado, as leis e regulamentos têm pressionado as indústrias para considerar os riscos ambientais na manufatura. Com o propósito de avaliar alternativas ao método convencional de lubri-refrigeração, foi estudada a viabilidade da técnica de refrigeração otimizada, onde o fluido de corte é aplicado à mesma velocidade periférica do rebolo, penetrando na região de corte com menos turbulência. Também foi analisada a técnica da Mínima Quantidade de Lubrificação (MQL), na qual o grande volume de fluido de corte é substituído por um jato de ar contendo uma quantidade ínfima de lubrificante. Os métodos foram comparados através da análise de desempenho durante o processo de retificação (forças de corte, emissão acústica, energia de retificação) e pela caracterização dos corpos de prova (rugosidade, danos subsuperficiais) e do rebolo (relação G). A profundidade de corte e o efeito do "spark-out" também formaram parte do escopo deste trabalho. Os resultados obtidos mostraram que a profundidade de corte exerce grande influência durante o processo... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The success of structural ceramics in most applications depends not only on the materials properties and component design, but also the quality of machined products. One factor usually mentioned as a barrier to the wide use of ceramics is the lack of reliability of ceramic components, because the variability on the mechanical strength caused by defects that can be impaired in the grinding process. The grinding of ceramics, as much as with steel grinding is performed generally with excess of cutting fluids (coolants). The use of coolants results in serious ecological, physiological and economic issues. Since last decade the public opinion, the market, the laws and regulations have pushed the industries to consider the environmental risks in the manufacturing process. Then, in order to evaluate alternatives to the conventional method of cooling and lubrication, it was studied the viability of the optimized technique, where the cutting fluid is applied to the same peripherical speed of the wheel, penetrating in the cutting zone with less turbulence. Also, it was verified the technique of Minimum Quantity of Fluid (MQF), where a large amount of cutting fluid is replaced by an air compressed flow containing a small quantity of lubricant. The methods were compared through performance analysis during the grinding process (cutting forces, acoustic emission and specific grinding energy) and by characterization of specimens (roughness, subsurface damage) and wheel (G ratio). The depth of cut and the effect of "spark-out" were part of the scope of this work too. The results obtained showed that the depth of cut has great influence during the process and in the characterization of ceramics, while "spark-out" does not seem to be so significant. Another conclusion is that MQF is not viable in ceramics grinding with the working conditions proposed. The results obtained... (Complete abstract, click electronic access below)
Mestre
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Luber, Martin [Verfasser]. "Strafverteidigung im Nürnberger Juristenprozess am Beispiel des Angeklagten Oswald Rothaug. / Martin Luber." Berlin : Duncker & Humblot, 2018. http://d-nb.info/1238442226/34.
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Macedo, Felipe Tadeu Barata de. "Simulação da adução de meio lubri-refrigerante na retificação com rebolos estruturados." reponame:Repositório Institucional da UFSC, 2013. https://repositorio.ufsc.br/handle/123456789/106612.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia Mecânica, Florianópolis, 2008Made available in DSpace on 2013-12-05T21:43:02Z (GMT). No. of bitstreams: 1 275230.pdf: 3754548 bytes, checksum: 07a6d5d99c9a4f9596333a2a08329d4e (MD5)
O meio lubri-refrigerante tem um papel fundamental no processo de retificação, uma vez que este gera calor significativamente, decorrente de atrito e deformações plásticas. O calor formado pode provocar danos térmicos e instabilidade dimensional dos componentes fabricados, assim como aumentar o desgaste da ferramenta abrasiva. Por este motivo, estudos têm sido feitos para verificar a influência do modo de aplicação e atuação do meio lubri-refrigerante nesse processo. Este trabalho tem como foco o estudo e a compreensão dos fenômenos que envolvem a forma como o meio lubri-refrigerante é injetado na interface rebolo-peça, e o modo como o escoamento se comporta no interior da cavidade de corte. As ferramentas utilizadas neste estudo foram as simulações computacionais. Para avaliar as formas de injeção de fluido, foram consideradas as tubeiras do tipo sapata, analisando a maneira de como os parâmetros de corte, pressão de injeção, posicionamento e geometria da tubeira influenciam no escoamento. Por outro lado, uma vez que o escoamento tenha atingido a cavidade de corte, estudou-se a influência dos grãos abrasivos sobre o fluxo de fluido. Para que fosse possível investigar os efeitos da presença dos grãos sobre o escoamento, a sua posição na superfície do disco de retificação deveria ser bem definida. Assim, como referência para este estudo, foram utilizados os rebolos estruturados, que têm a posição de cada grão abrasivo pré-definida em sua estrutura.
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Pennerman, Kayla Kara. "Development of Methods for Structural Characterization of Pantoea stewartii Quorum-Sensing Regulator EsaR." Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/25297.
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The LuxR family of proteins serves as quorum-sensing transcriptional regulators in proteobacteria. At high population densities, a small acyl-homoserine lactone (AHL) molecule, produced by a LuxI homologue, accumulates in the environment. The LuxR proteins bind to their respective AHL when the ligand accumulates to sufficient levels. Once bound to AHL, the holoproteins usually become functional as transcriptional activators. However, there is a subset of LuxR homologues, the EsaR subfamily, which is active without the AHL ligand and becomes inactivated once bound to it. EsaR is the best understood member of this subfamily. It controls virulence in the corn pathogen Pantoea stewartii ssp. stewartii.
Solubility issues have previously limited structural studies of LuxR homologues as the proteins could not be purified without the AHL ligand. A soluble recombinant EsaR protein, HMGE, is biologically active and can be purified in the absence and presence of AHL, unlike most other LuxR homologues. Using HMGE, amino acid substitutions and Förster resonance energy transfer (FRET), experimental methods were designed for determining the dimerization interface of EsaR and for testing the hypothesis that EsaR undergoes a conformational shift when presented with the AHL ligand.
To identify residues of the dimerization interface, heterodimerization assays were designed, involving either coexpression or coincubation of wild-type EsaR and variant HMGE proteins. In this assay, the inability of the proteins to copurify by nickel affinity chromatography would indicate that the modified residue(s) are important for dimerization of EsaR. To determine the conformational change that EsaR undergoes when bound to the AHL ligand, a FRET assay was developed to estimate the distances between amino acid residues in the absence and presence of AHL. Future work will have to include a few modifications to the methods and/or control experiments. This study provides the basis upon which the present methods can be further developed and later used for structural studies of EsaR.Master of Science
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Souza, Augusto Guelli Ulson de. "Investigação experimental da transferência de calor de superfícies estendidas aquecidas para sprays de fluido refrigerante." Florianópolis, SC, 2011. http://repositorio.ufsc.br/xmlui/handle/123456789/95259.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia MecânicaMade available in DSpace on 2012-10-25T23:18:20Z (GMT). No. of bitstreams: 1 298834.pdf: 6195502 bytes, checksum: 3420709e72805082e2b0482feb416525 (MD5)
Com o aumento da miniaturização dos componentes eletrônicos, gerou-se a necessidade do projeto de sistemas de dissipação de calor mais eficientes, compactos, silenciosos e com capacidade de remoção de altos fluxos de calor. A tecnologia de resfriamento por spray vem sendo vista como uma possível solução para o preenchimento desta lacuna, especialmente quando acoplada a sistemas de refrigeração compactos. O enorme potencial desta nova tecnologia é refletido no grande aumento do número de publicações na área de resfriamento por spray nos últimos anos; porém existe ainda a escassez de estudos de spray cooling empregando fluidos refrigerantes como fluidos de operação. Este trabalho tem por objetivo analisar experimentalmente o fenômeno de resfriamento de superfícies estendidas de cobre por spray de fluido refrigerante. Uma bancada experimental foi construída para a análise do desempenho da transferência de calor em três superfícies: superfície plana, superfície com espuma metálica e superfície aletada com canais radiais. O comportamento do coeficiente de transferência de calor por convecção foi analisado em função da vazão mássica de fluido refrigerante e pressão na qual o spray era exposto. As seguintes condições de testes foram realizadas: pressão interna da câmara de testes de 5 e 6 bar, vazão mássica de fluido refrigerante de 3 e 5 quilogramas por hora, distância entre o bico injetor e a base das superfícies de 17 mm, grau de sub-resfriamento do fluido de 5ºC e fluxo de calor dissipado na superfície de teste de 0 a 40 W/cm2. Os resultados apontam que o aumento da vazão mássica do fluido refrigerante resulta em maiores coeficientes de transferência de calor, enquanto que a eficiência do spray é reduzida. O aumento da pressão na qual o fluido é exposto intensifica a transferência de calor entre a superfície e o fluido, aumentando também a eficiência do spray. O melhor desempenho de transferência de calor foi obtido utilizando-se a superfície com acoplamento de espuma metálica sobre a superfície. O fluxo de calor crítico não sofreu efeito da variação da geometria da superfície. Este estudo contribuiu para a melhor compreensão do fenômeno de resfriamento por spray em superfícies estendidas.
The increasing of electronic components miniaturization has generated the need for more efficient, compact and quiet heat sinks designs, capable of removing high heat fluxes. The Spray Cooling technology is being seen as a possible solution to fill this gap, especially when attached to compact refrigeration systems. The huge potential of this new technology is reflected on the large increase of the number of publications in the Spray Cooling area in the last few years; but there is still a lack of studies of spray cooling using refrigerants as working fluid. The main objective of this research is the experimental analysis of the Spray Cooling phenomena in enhanced cooper surfaces, using refrigerant. A testing bench was built to investigate the performance of heat transfer in three different surfaces: flat surface, surface with a copper-foam metal cover and finned surfaces with radial channels. The behavior of the heat transfer coefficient was analyzed as a function of the refrigerant mass flow and the pressure at which the spray was exposed. The tests condition were: internal pressure of the testing chamber of 5 and 6 bar, refrigerant mass flow of 3 and 5 kilograms per hour, distance between the nozzle and the base of the testing surface of 17 millimeters, sub-cooling degree of 5ºC and heat flux from 0 to 40 W/cm2. The results show that the increasing of the refrigerant mass flow results in higher heat transfer coefficient, while the boiling efficiency is reduced. The increase of the pressure which the fluid is exposed to enhanced the heat transfer between the fluid and the surface, increasing the boiling efficiency as well. The best performance of heat transfer was achieved in the surface with metal foam cover. The critical heat flux was not sensible to the surface geometry. This research contributed to a better understanding of spray cooling phenomena in extended surfaces.
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Tshikoji, Mbumba Sylvain. "La quête du bonheur partagé à travers la triade éthique africaine Luba-Kasaî." Doctoral thesis, Université Laval, 2017. http://hdl.handle.net/20.500.11794/27690.
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Trois tendances polarisent le débat philosophique en Afrique. La première tendance considère la redécouverte des traditions et coutumes africaines comme la seule voie pour faire advenir le développement et le bien-être des peuples. Cette position est apparue dogmatique pour autant qu'elle fonde sa démarche sur des cultures repliées sur elles-mêmes. La deuxième tendance, elle, proclame le vide de la rationalité et de la pensée dans les traditions africaines, et annonce par-là la conversion à la science et à la technologie occidentale. Cette position est aussi dogmatique parce qu'elle nie à l'Afrique toute forme de rationalité. La troisième prend la voie de la réconciliation entre la tradition et la modernité, en mettant à l'avant-plan le dynamisme des cultures africaines porté par le souci d'ouverture et d'intégration des schèmes de progrès de la modernité. Pour les tenants de cette tendance donc, la tradition et la modernité doivent s'interpréter et s'impliquer mutuellement pour une vitalité sans faille. Mais à bien voir la question, ce débat est demeuré théorique et les différentes tendances ont éludé la vraie question de l'existence humaine des peuples africains qui, à notre sens, reste celle du bonheur partagé. Ces tendances auraient dû partir des cas concrets tirés des traditions et coutumes africaines pour étoffer une philosophie cohérente susceptible de faire hâter le développement et le bien-être des peuples. Concret et pratique, le présent travail propose une réflexion sur l'éthique du bonheur partagé cultivée par le peuple Luba-Kasaï, avec ses implications sociales et politiques dans la vie de tous les jours. L'enjeu consiste à montrer que, chez le peuple Luba-Kasaï, la visée éthique de l'existence humaine est le bonheur. Loin d'être individuelle, la quête du bonheur partagé concerne aussi toute la communauté (famille, clan, village) et passe par les médiations institutionnelles et symboliques. Car pour être possible, le bien-vivre doit dépasser le face à face des relations individuelles et s'étendre à la dimension transpersonnelle, sociale et institutionnelle. Cette perception du bonheur régit l'organisation sociale, notamment en permettant à chaque membre de s'accomplir socialement, en favorisant la participation de tous à la gestion de la Cité et du bien commun. Ce qui nécessite l'instauration des structures politiques et sociales adéquates, respectueuses des droits, de la dignité humaine et des libertés. Ce travail a aussi comme objectifs de montrer que l'avènement du bien-être de l'Afrique ne dépend pas uniquement du processus de conversion au modèle occidental comme le seul dont l'Afrique ait besoin pour son développement. Il s'agit de montrer la nécessité de la voie de la réconciliation capable d'articuler dynamiquement la modernité occidentale et la tradition africaine, le principe d'ouverture, d'intégration et d'universalisation permettant l'enrichissement dans la réciprocité ; montrer, à partir de la culture luba-kasaï, que dans les pays africains, chaque culture doit trouver les socles éthicophilosophiques du développement harmonieux et d'une heureuse organisation étatique.For sometime, most intellectuals have agreed that the African philosophical debate has evolved around three tendencies. The first propensity has been that the promotion of traditions and local cultures is the unique and sole venue that would yield the development as well as the happiness of nations. Such a bias has proven to be dogmatic as it is rooted in the belief that people need to be self-reliant. The second proclivity claims that there is no rationale in the idea of relying solely on African traditions, when it is possible to evolve into a synergic symbiosis that includes both modern science and technology. The latter is also quite dogmatic, as it invalidates any shape or form of African rationality. The third current attempts to propitiate traditions and modernism, while putting forward the exhilaration of African customs, and being cognizant of the need to maintain openness and integration of the betterment that a contemporary society might infuse. In this respect, traditions and modernism must symphonize and assimilate their values in order to sustain their essence. However, when applying the sniff test, this debate has remained fruitless; these theories have eluded the question of addressing the existence of African nations, which, from our stand point, remains one of shared happiness. These predilections should have utilized concrete examples from African customs, in order to enhance a coherent philosophy that would propel the development and the happiness of nations. A more practical approach is proposed and illustrated in these writings, which bring forth an ethical rationale of the shared happiness we find among the People of Luba heritage, despite its socio-political implications. Within the ethnic Luba-Kasai, the human goal of everyday living is happiness. Far from being individually centered, the search for a shared happiness is the concern of the entire society (family, clan or village), extending through institutional and symbolic mediation. This perception of happiness runs the social organization, allowing the contribution from as well as the participation of each individual, to the management of the city and the commonwealth. This requires the integration of social and political structures that would advance everyone's rights, dignity and liberty. We therefore insist that the oncoming realization of African happiness does not rest uniquely on an occidental conversion model. It will become a reality when we coalesce western contemporary systems, African traditional values, openness, integration that would lead to reciprocal and mutual enrichment. It is only within such premises, starting within the Luba-Kasaï tribes, that each African nation, each African culture, will find the missing ethical and philosophical links to a more harmonious societal organization.
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Geissinger, Jared Scott. "Structure-Function Analysis of the EsaR N-terminal Domain." Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/46190.
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The LuxR protein family is a class of quorum-sensing regulated bacterial transcription factors that alter gene expression as a function of ligand detection. This coincides with a high population density and/or a low rate of signal ligand diffusion. The majority of LuxR proteins are activated only in the presence of the signal ligand, an acyl-homoserine lactone (AHL). EsaR, from the corn pathogen Pantoea stewartii, represents a subset of LuxR homologues that are active in the absence of AHL and deactivated by its presence. The mechanism by which EsaR responds to AHL in a manner opposite to that of the majority of LuxR homologues remains elusive. Unlike the majority of LuxR homologues, which require AHL for purification, EsaR can be purified and biochemically investigated in the absence and presence of AHL. This work sought to answer questions regarding the structure-function relationship of the LuxR homologue, EsaR.
Fluorescence anisotropy was used to determine the relative DNA-binding affinity of wild type EsaR and three AHL-independent EsaR variants in the presence and absence of AHL. This enabled for quantitative analysis of the relative binding affinities of these AHL-independent variants for the EsaR binding site, the esa box. The results demonstrate that one AHL-independent EsaR variant has a slightly higher affinity for the esa box in the presence, rather than the absence of AHL. The affinity of the other two for the DNA is not impacted by AHL, potentially due to an inability to transduce the signal of ligand detection to the DNA binding domain.
Constructs containing only the EsaR N-terminal domain (NTD) were also developed. These constructs circumvented solubility issues associated with the full-length protein, allowing for additional biochemical analysis. It was determined that the EsaR NTD alone is sufficient for multimerization and ligand binding. Additionally, preliminary X-ray crystallography efforts have established some of the early parameters required to solve the crystal structure of the EsaR ligand binding domain in both the presence and absence of AHL. If pursued, these structures would be the first solved of a LuxR homologue ligand binding domain in both the presence and absence of the native AHL, potentially demonstrating the conformational change that occurs as a result of ligand binding. Collectively, these findings have established some of the groundwork required to resolve the question of what sort of conformational changes occur in EsaR as a result of ligand binding.Master of Science
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Brameyer, Sophie [Verfasser], and Ralf [Akademischer Betreuer] Heermann. "Cell-cell communication via LuxR solos in Photorhabdus species / Sophie Brameyer. Betreuer: Ralf Heermann." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2015. http://d-nb.info/1069491438/34.
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Bös, Friedrich [Verfasser], Max [Akademischer Betreuer] Wardetzky, Max [Gutachter] Wardetzky, Gert [Gutachter] Lube, and Etienne [Gutachter] Vouga. "Origami Cylinders / Friedrich Bös ; Gutachter: Max Wardetzky, Gert Lube, Etienne Vouga ; Betreuer: Max Wardetzky." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2018. http://d-nb.info/1157094481/34.
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Freire, Antonio J?lio Garcia. "A natureza da alma e o clinamen: a??o e liberdade em Lucr?cio." Universidade Federal do Rio Grande do Norte, 2014. http://repositorio.ufrn.br:8080/jspui/handle/123456789/16468.
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Previous issue date: 2014-05-09The concept of freedom and his presupposition, the free will or libera voluntas in Lucretius relies on the notion of clinamen (declination), an occasional and random motion of atoms, inaccessible to experience. It is endowed with a complex movement provided by spontaneity, without the need for mechanical causes. The action of perceiving (sensus) is selfconsciousness, according to which this will, illuminated by previous experiences (sensory, intellectual or emotional) of the soul, takes advantage of the freedom and own spontaneity of atomic motions to drive them to a perceived direction and chosen. On the other hand, if we consider that the declination has a predominant role for the acts of will, we are facing other problems and questions. There is always the choice of a determined action and, therefore, even if the individual is facing a need to act, is possible choose to do not continue finish this action. Thereby, the will is related to conditions that are originate, ultimately, from the images formed randomly in space and impress the soul: the simulacra of desire and pleasure. The declination itself is a very important notion in this research, in order to emphasize the relationship between the freedom and the kinetic of elements. The approach developed in this work had as main objective to investigate the philosophy of nature and the soul in Lucretius, their constituents and movement, as well as demonstrating how the notion of clinamen articulates with the concepts of image, desire and pleasure, proposing a possible interpretation for the declination as an indeterminate and ethical foundation of freedom
A no??o de liberdade e o seu pressuposto, a vontade livre ou libera voluntas em Lucr?cio se apoia no conceito de clinamen (declina??o), um movimento ocasional e fortuito dos ?tomos, inacess?vel ? experi?ncia. Trata-se de um movimento complexo dotado de espontaneidade, sem a necessidade de causas mec?nicas. A a??o de perceber (sensus) ? a consci?ncia de si, em fun??o de qual esta vontade, iluminada por experi?ncias anteriores (sensitivas, intelectuais ou afetivas) da alma, tira proveito da liberdade ou espontaneidade pr?pria dos movimentos at?micos para dirigir ou n?o estes ?ltimos a uma dire??o percebida e escolhida. Por outro lado, atribuir ? declina??o um papel predominate para os atos da vontade encerra outros problemas. Sempre existe a escolha sobre uma dada a??o e, portanto, mesmo que o indiv?duo se encontre frente a uma necessidade do agir, ? poss?vel escolher n?o prosseguir e concluir a a??o. Desse modo, a vontade encontra-se associada ?s afec??es que s?o originadas, em ?ltima an?lise, das imagens que se formam de maneira aleat?ria no espa?o e impressionam a alma: os simulacros do desejo e do prazer. A declina??o investe-se de import?ncia na presente pesquisa, a fim de enfatizar as rela??es entre a liberdade e a cin?tica dos elementos. Isto posto, a abordagem desenvolvida neste trabalho teve como objetivos principais investigar a filosofia da natureza do mundo e da alma em Lucr?cio, seus constituintes e movimento, al?m de demonstrar como a no??o do clinamen se articula com as imagens, o desejo e o prazer, propondo uma interpreta??o poss?vel para a declina??o como fundamento indeterminado e ?tico da liberdade
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Qin, Nan. "Analysis of the Regulons Controlled by Transcriptional Regulators LuxR and LitR in Vibrio fischeri." Diss., Virginia Tech, 2008. http://hdl.handle.net/10919/28433.
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Quorum sensing is a bacterial signaling system that controls gene expression in a population density-dependent manner. In Gram-negative proteobacteria, the cell density control of luminescence was first observed in the symbiotic marine bacterium Vibrio fischeri and this system is one of the best studied quorum sensing systems. Two-dimensional sodium dodecyl sulfate-polyacrylamide (2D-SDS) gel electrophoresis analysis previously identified several non-Lux proteins in V. fischeri MJ-100 whose expression was dependent on LuxR and 3-oxo-hexanoyl-L-homoserine lactone (3-oxo-C6-HSL). A lacZ reporter was used to show that the promoters for qsrP, acfA, and ribB were directly activated via LuxR-3-oxo-C6-HSL in recombinant Escherichia coli. The sites of transcription initiation were established via primer extension analysis. Based on the position of the lux box-binding site near position â 40, all three promoters appear to have a class II-type promoter structure. Real-time reverse transcription-PCR was used to study the temporal expression of qsrP, acfA, and ribB during the exponential and stationary phases of growth, and electrophoretic mobility shift assays were used to compare the binding affinities of LuxR to the promoters under investigation.
In order to fully characterize the LuxR regulon in V. fischeri ES114, microarray analysis was performed in the Greenberg lab (University of Washington) and 18 LuxR-3-oxo-C6-HSL regulated promoters were found including 2 genes (qsrP and acfA) identified previously in MJ-100 in addition to the well-studied lux operon. In collaboration with them, full-length purified LuxR protein was used to show direct interaction between the LuxR protein and 7 genes/operons newly identified out of 13 genes/operons examined. The binding affinity between LuxR proteins and those genes was also measured.
Based on the sequence of the lux boxes of the known genes regulated by LuxR and LitR, a position specific weight matrix (PSWM) was created and used to search through the intergenic regions of the V. fischeri ES114 genome. Some potential LuxR and LitR-regulated genes with high score were tested experimently to confirm direct activation. For the LuxR regulon, these possible LuxR-regulated promoters were cloned into a lacZ reporter and tested for their LuxR dependence. Beyond the genes found in microarray, the promoter of the intergenic region VFA0658-0659 was found to be activated by LuxR and 3-oxo-C6-HSL. For the LitR regulon, two LitR-regulated genes found in the microarray were also identified using PSWM and confirmed by real-time PCR to be dependent on LitR for expression. EMSA experiments showed that LitR can specifically bind to the litR boxes of LitR-regulated genes, litR and VF0170 which confirmed that the regulation is direct.Ph. D.
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Hilber, Botho Hermann Johannes [Verfasser], Birgit [Akademischer Betreuer] Luber, and Heinz K. [Akademischer Betreuer] Höfler. "Klinisch-pathologische Bedeutung des Signalweges des Rezeptors des epidermalen Wachstumsfaktors (EGFR) beim Adenokarzinom des gastroösophagealen Übergangs Typ I (Barrett-Karzinom) / Botho Hermann Johannes Hilber. Gutachter: Birgit Luber ; Heinz K. Höfler. Betreuer: Birgit Luber." München : Universitätsbibliothek der TU München, 2013. http://d-nb.info/1035274361/34.
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Callahan, Sean M. (Sean Michael) 1966. "The quorum-sensing regulation of Vibrio fischeri : novel components of the autoinduce/LuxR regulatory circuit." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/85290.
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Trott, Amy Elizabeth. "Amino Acid Residues in LuxR Critical for its Mechanism of Transcriptional Activation during Quorum Sensing." Thesis, Virginia Tech, 2000. http://hdl.handle.net/10919/34070.
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Vibrio fischeri, a symbiotic bioluminescent bacterium, serves as one of the best understood model systems for a mechanism of cell-density dependent bacterial gene regulation known as quorum sensing. During quorum sensing in V. fischeri, an acylated homoserine chemical signal (autoinducer) is synthesized by the bacteria and used to sense their own species in a given environment. As the autoinducer levels rise, complexes form between the autoinducer and the N-terminal domain of a regulatory protein, LuxR. In response to autoinducer binding, LuxR is believed to undergo a conformational change that allows the C-terminal domain to activate transcription of the luminescence or lux operon. To further understand the mechanism of LuxR-dependent transcriptional activation of the lux operon, PCR-based site-directed mutagenesis procedures have been used to generate alanine-substitution mutants in the C-terminal forty-one amino acid residues of LuxR, a region that has been hypothesized to play a critical role in the activation process. An in vivo luminescence assay was first used to test the effects of the mutations on LuxR-dependent activation of the lux operon in recombinant Escherichia coli. Luciferase levels present in cell extracts obtained from these strains were also quantified and found to correlate with the luminescence results. Eight strains encoding altered forms of LuxR exhibited a "dark" phenotype with luminescence output less than 50% and luciferase levels less than 50% of the wildtype control strain. Western immunoblotting analysis with cell extracts from the luminescence and luciferase assays verified that the altered forms of LuxR were expressed at levels approximately equal to wildtype. Therefor, Low luminescence and luciferase levels could be the result of a mutation that either affects the ability of LuxR to recognize and bind its DNA target (the lux box) or to establish associations with RNA polymerase (RNAP) at the lux operon promoter necessary for transcriptional initiation. A third in vivo assay was used to test the ability of the altered forms of LuxR to bind to the lux box (DNA binding assay/repression). All of the LuxR variants exhibiting the "dark" phenotype in the luminescence and luciferase assay were also found to be unable to bind to the lux box in the DNA binding assay. Therefore, it can be concluded that the alanine substitutions made at these positions affect the ability of LuxR to bind to the lux box in the presence and absence of RNA polymerase. Another class of mutants exhibited wildtype phenotypes in the luminescence and luciferase assays but were unable to bind to the lux box in the DNA binding assay. The alanine substitutions made at these amino acid residues may be making contacts with RNAP that are important for maintaining the stability of the DNA binding region of LuxR. Alanine substitutions made at these positions have a defect in DNA binding at the promoter of the lux operon only in the absence of RNAP. None of the alanine substitutions made in the C-terminal forty-one amino acids of LuxR were found to affect activation of transcription of the lux operon without also affecting DNA binding. Taken together, these results support the conclusion that the C-terminal forty-one amino acids of LuxR are important for DNA recognition and binding of the lux box rather than positive control of the process of transcription initiation.Master of Science
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Dyszel, Jessica L. "Phenotypes of the LuxR Homolog, SdiA, in Salmonella and E. coli." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1243943752.
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Michael, Bindhu. "Detection of Heterologous bacterial pheromones by SdiA, A LuxR Homolog in Salmonella enterica serovar Typhimurium." The Ohio State University, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=osu1407404158.
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Weingärtner, Eduardo. "Influência do sistema de alimentação de fluido lubri-refrigerante na retificação com rebolos de CBN." Florianópolis, SC, 2005. http://repositorio.ufsc.br/handle/123456789/102572.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-graduação em Engenharia Mecanica.Made available in DSpace on 2013-07-16T01:19:18Z (GMT). No. of bitstreams: 0
O emprego de altas velocidades de corte no processo de retificação e a utilização de rebolos de CBN são tendências cada vez mais evidentes dentro do universo da usinagem. O processo de retificação caracteriza-se pela geração de grande quantidade de calor em função do atrito e deformações plásticas, onde a temperatura provocada pelo atrito aumenta com o aumento da velocidade de corte. O calor desenvolvido no processo é conduzido para a peça, para o grão abrasivo, para o ligante e para o meio, podendo acarretar danos metalúrgicos à peça e ser responsável por um desgaste prematuro do rebolo. Dentro deste contexto, o fluido lubri-refrigerante apresenta-se como um recurso indispensável para os processos abrasivos. A eficácia do fluido lubri-refrigerante depende de fatores, como a pressão, a vazão, o projeto da tubeira e assim também da velocidade de escoamento do fluido na saída da tubeira. Na retificação, devido às altas velocidades de corte empregadas, uma grande quantidade de ar é deslocada em torno da ferramenta rotativa, sendo formado um colchão de ar que reduz a eficiência da penetração do fluido na região de corte. Dentro deste contexto, diferentes concepções de alimentação de fluido vem sendo desenvolvidas, visto que uma otimização do processo pode ser alcançada quando uma maior quantidade de fluido é forçada para dentro da região de corte. Na indústria, é comum o emprego de tubeiras convencionais, como as de jato livre. No entanto, para otimizar o processo com este tipo de tubeira são necessárias altas pressões e velocidades de saída do fluido para vencer o colchão de ar, o que muitas vezes se torna economicamente inviável. Uma alternativa interessante é o emprego de tubeiras do tipo sapata. Com a sapata é possível aumentar o efeito de bombeamento do fluido para a região de corte, ao mesmo tempo em que é reduzido o efeito do colchão de ar. Isto ocorre porque a sapata é ajustada por retificação ao rebolo, funcionando como um raspador (scrapper), impedindo que o ar deslocado atinja a região de corte. Com o objetivo de avaliar a influência do sistema de alimentação de fluido lubri-refrigerante no processo de retificação, foram empregadas tubeiras dos tipos jato livre e sapata para diferentes condições de alimentação. Foram utilizados dois tipos de rebolos de CBN, sendo um com ligante resinóide e outro vitrificado. O material ensaiado foi um ferro fundido nodular com designação GGG70. Como fluido lubri-refrigerante foi empregada uma emulsão com 5% de óleo em água. Os resultados obtidos mostram que com o emprego da sapata é possível alcançar melhores resultados de desgaste radial do rebolo e qualidade da superfície retificada mesmo para menores vazões de fluido.
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Volper, Julien. "Un art entrevu d'Afrique Centrale : analyse stylistique et iconographique des masques dits luba du Katanga et du Kasaï (République Démocratique du Congo)." Paris 1, 2007. http://www.theses.fr/2007PA010709.
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De manière générale, l'étude du masque suit des règles analytiques dérivées de celles de la statuaire, qui ne prennent pas en compte le caractère « vivant» de ce type d'oeuvre. Dans ce travail, la question de la méthodologie analytique est abordée au travers d'études d'auteurs, de réflexions tournant autour de la définition du terme masque, et d'un historique raisonné de l'appréhension artistique de cet objet en Europe. Ce travail aboutit à l'élaboration d'une méthode personnelle permettant de traiter du masque en général. Ladite méthode met en valeur les liens formels qui unissent les masques entre eux, ou les rapprochent d'autres productions artistiques. D'un point de vue plus spécifique, les masques des Luba du Katanga et du Kasaï, sujets principaux de la thèse, profitent de cette relecture méthodologique. Les données formelles et stylistiques obtenues sont mises à contribution lorsque la symbolique et l'aspect socio-culturel des œuvres du corpus sont étudiés. Avec l'aide de ces résultats et de la prise en compte d'autres sources, pour certaines inédites, des hypothèses d'utilisation jamais envisagées, ou peu approfondies, sont mises en valeur, alors que d'autres hypothèses antérieures se voient réfutées.