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Engels, Sabine. "Regulation der clp-Genexpression durch ClgR und Definition des ClgR-Regulons aus Corynebacterium glutamicum." [S.l.] : [s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=973949759.
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Іванченко, О. О., and В. А. Бісюк. "Платформа CLR в середовищі ОС Windows." Thesis, КОД, 2012. http://dspace.kntu.kr.ua/jspui/handle/123456789/4407.
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Fuchs, Franz Xaver. "Clock-feedthrough compensation in MOS sample-and-hold circuits." Thesis, University of Plymouth, 2001. http://hdl.handle.net/10026.1/2354.
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All MOS sample-and-hold circuits suffer to a greater or lesser extent from clock-feedthrough (CLFT), also called charge-injection. During the transition from sample to hold mode, charge is transferred from an MOS transistor switch onto the hold capacitor, thus the name charge-injection. This error can lead to considerable voltage change across the capacitor, and predicting the extent of the induced error potentials is important to circuit designers. Previous studies have shown a considerable dependency of CLFT on signal voltage, circuit impedances, clock amplitude and clock fall-time. The focus of this work was on the signal dependency of the CLFT error and on the CLFT induced signal distortion in open-loop sample-and-hold circuits. CLFT was found to have a strongly non-linear, signal dependent, component, which may cause considerable distortion of the sampled signal. The parameters influencing this distortion were established. It was discovered that distortion could be reduced by more than 20dB through careful adjustment of the clock fall-rate. Several circuit solutions that can help reduce the level of distortion arising from CLFT are presented. These circuits can also reduce the absolute level of CLFT. Simulations showed their effectiveness, which was also proven in silicon. The CLFT reduction methods used in these circuits are easily transferable to other switched-capacitor circuits and are suitable for applications where space is at a premium (as, for example, in analogue neural networks). A new saturation mode contribution to CLFT was found. It is shown to give rise to increased CLFT under high injection conditions.
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Fruja, Nicu Georgian. "Type safety of C# and .Net CLR /." Zürich : ETH, 2007. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17003.
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Monteiro, João Gonçalo Tereno Verfasser], Bernd [Akademischer Betreuer] [Lepenies, Ralph Akademischer Betreuer] Goethe, and Reinhard [Akademischer Betreuer] [Schwartz-Albiez. "A C-type lectin receptor (CLR)-Fc fusion protein library as a toolbox to detect novel CLR ligands and the interplay of CLR/virus interactions / João Gonçalo Tereno Monteiro ; Bernd Lepenies, Ralph Goethe, Reinhard Schwartz-Albiez." Hannover : Stiftung Tierärztliche Hochschule Hannover, 2019. http://d-nb.info/119175278X/34.
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Monteiro, João Gonçalo Tereno [Verfasser], Bernd [Akademischer Betreuer] Lepenies, Ralph [Akademischer Betreuer] Goethe, and Reinhard [Akademischer Betreuer] Schwartz-Albiez. "A C-type lectin receptor (CLR)-Fc fusion protein library as a toolbox to detect novel CLR ligands and the interplay of CLR/virus interactions / João Gonçalo Tereno Monteiro ; Bernd Lepenies, Ralph Goethe, Reinhard Schwartz-Albiez." Hannover : Stiftung Tierärztliche Hochschule Hannover, 2019. http://d-nb.info/119175278X/34.
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Crystal, Raphael. "High wire : chamber ballet in five movements for multiple woodwind player (piccolo, E� clar., alto sax., bass clar.) and piano and written report High wire : a tonal and serial composition." Virtual Press, 2004. http://liblink.bsu.edu/uhtbin/catkey/1292541.
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High Wire is a chamber ballet in five movements for multiple woodwind player (piccolo, Eb clarinet, alto saxophone, bass clarinet) and piano. It was inspired by Frederick H. Graham's Wait For The Muncie Boys: Indiana's Early Circuses, and was first performed, with choreography by Michele Kriner, at a concert of the Middletown Arts Project on January 26, 2003. The work is somewhat unusual in that it is both tonal and serial. It evokes popular musical styles of the turn of the twentieth century, with particular reference to circus music, and yet it is based on a twelve-tone series and generally adheres to strict serial techniques. The genesis of the work, the relationship of the music to the choreography, and the way in which two rather different musical sensibilities are reconciled are discussed in the written report that serves as an introduction to the score. A recording of the first performance is included in the side-pocket.School of Music
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Wilson, K. Craig. "Using marginal analysis to load Combat Logistics Force (CLF) ships." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1994. http://handle.dtic.mil/100.2/ADA293136.
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Thesis (M.S. in Management) Naval Postgraduate School, December 1994.Thesis advisor(s): Paul J. Fields, Katsuaki L. Terasawa. "December 1994." Includes bibliographical references. Also available online.
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Zhang, Qiang. "Genetic and Expression Analyses of the 'Nkrp1-Clr' Gene Cluster." Thèse, Université d'Ottawa / University of Ottawa, 2012. http://hdl.handle.net/10393/23271.
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Natural killer (NK) cells, lymphocytes of the innate immune system, can recognize a wide array of cells via several receptors families such as Ly49 and NKR-P1. The Nkrp1 gene family encode for C-type lectin-like receptors which can recognize their ligands, Clr, on target cells. Nkrp1 and Clr genes are intertwined in the NK gene complex and are thus inherited together. The Nkrp1-Clr genes in 129S6 and BALB/c mouse strains show significant sequence polymorphism compared to those of C57BL/6 mice while the overall gene organization and gene number are conserved. RT-PCR was utilized to study the expression of individual Nkrp1-Clr genes. In situ hybridization was performed to validate expression results from RT-PCR, as well as to verify the cell types in which Nkrp1-Clr genes are expressed. Surprisingly, our expression studies reveal an interesting pattern of expression of Nkrp1 and Clr genes not only in lymphoid tissues but also in the epithelial cells of the intestine, kidney, eye and lung, the myocytes of the heart and skeletal muscle, and possibly some endothelial cells, indicating novel functions of NK cells in these tissues.
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Mock, Philip J. "Measuring Combat Logistics Force (CLF) Adequacy in Supporting Naval Operations." Thesis, Monterey, California. Naval Postgraduate School, 2012. http://hdl.handle.net/10945/6837.
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Approved for public release, distribution unlimitedWe uses the existing outputs of the Combat Logistics Force (CLF) Planner tool to (1) assess the minimum level of support required for a specified force in a multi-stage naval combat scenario and (2) compare CLF adequacy, surplus mission capability, and logistics shortfalls that a minimum level of support provides to combat forces of varying compositions. We examine the potential impact of the transition from a traditional nuclear-powered aircraft carrier strike group to a more distributed conventionally-powered one. We find that the logistical demands of a small conventionally powered carrier strike group with comparable striking power require significant increases in CLF end strength, and therefore that logistical supportability must be an integral part of future fleet planning.
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Cederlund, Petter. "Cross-Language Information Retrieval : En granskning av tre översättningsmetoder använda i experimentell CLIR-forskning." Thesis, Högskolan i Borås, Institutionen Biblioteks- och informationsvetenskap / Bibliotekshögskolan, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-20775.
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The purpose of this paper is to examine the three main translation methods used in experimental Cross-language Information Retrieval CLIR research today, namely translation using either machine-readable dictionaries, machine translation systems or corpus-based methods. Working notes from research groups participating in the Text Retrieval Conference TREC and the Cross-Language Evaluation Forum CLEF between 1997 and 2000 have provided the main source material used to discuss the possible advantages and drawbacks that each method presents. It appears that all three approaches have their pros and cons, and because the different researchers tend to favour their own chosen method, it is not possible to establish a "winner approach" to CLIR translation by studying the working notes alone. One should remember however that the present interest in cross-language-applications of information retrieval has arisen as late as in the 1990s, and thus the research is yet in its early stages. The methods discussed in this paper may well be improved, or perhaps replaced by others in the future.Uppsatsnivå: D
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Naffadi, Hind. "The role of adrenomedullin and its receptor (CLR/RAMP3) in breast cancer." Thesis, University of Sheffield, 2018. http://etheses.whiterose.ac.uk/22203/.
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Abbas, Syed Zaheer. "Modelling of sorption enhanced chemical looping steam reforming (SE-CLSR) of methane in a packed bed reactor." Thesis, University of Leeds, 2016. http://etheses.whiterose.ac.uk/15200/.
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In the sorption enhanced steam methane reforming (SE-SMR) process, hydrogen (H2) can be produced in concentration up to 98 vol. % (dry basis) in a single reactor packed with a mixture of reforming catalyst and carbon dioxide (CO2) sorbent. This is defined as pre-combustion capturing of CO2 and the high purity H2 produced can be used as a fuel for electricity generation, synthesis of ammonia-derived fertilisers, or hydrotreating of naphtha and other heavy gas oil in petroleum refinery. A cyclic operation between the production of H2 and regeneration of CO2 sorbent is required, but the energy demand for the sorbent regeneration is high. A proposed method to decrease this energy demand is to couple SE-SMR with chemical looping (CL), which naturally separates the nitrogen (N2) from the syngas via the highly exothermic cyclic oxidation with air of a metallic material, which acts as the reforming catalyst when reduced (oxygen transfer material or ‘OTM’). The combination of SE-SMR and CL makes the process energy efficient and eliminates the need for (i) high temperature as compared to the conventional steam methane reforming (SMR) process (typical temperature range is 750- 950°C), (ii) the water gas shift (WGS) reactors downstream of the reformer, and (iii) external heating using the natural gas fuel in the reformer. However the H2 generation of a high purity from one reactor operation is intermittent, as part of a cyclic operation, with the reactor alternately operating in Fuel Reactor mode (FR), with fuel and steam feed or Air Reactor mode (AR), with air feed. Adsorption of CO2 shifts the equilibrium of reaction towards more H2 production and ultimately increases the efficiency of the process towards H2 production. Production of H2, CH4 conversion and overall efficiency of the process depend upon many operating parameters. The effects of inlet temperature, reactor pressure, molar steam to carbon ratio (S/C) in the feed, and gas mass velocity on the SE-SMR and the sorption enhanced chemical looping steam reforming (SE-CLSR) of methane processes is reported in this thesis. The formulation of the SE-CLSR process model requires the modelling of packed bed reactors. This mathematical modelling covers various individual models (sub-models) for; SMR, SE-SMR, OTM reduction and oxidation of reduced OTM. The gPROMS model builder 4.1.0® is used to solve the model equations. In this work, an experimental IV kinetics study and model of SMR process over 18 wt. % NiO/α-Al2O3 catalyst are presented for an adiabatic fixed bed reactor in the temperature range of 300-700°C at 1 bar pressure. The model is validated by comparing the results with the experimental data obtained as part of this work. The simulation results are in excellent agreement with the experimental results. The equilibrium results are generated using Chemical Equilibrium with Applications (CEA) software. The effect of various operating parameters (temperature, pressure and S/C) on the CH4 and water conversion (%) is modelled and compared with the equilibrium values. The mathematical model of SE-SMR was developed based on the industrial operating conditions of temperature and pressure. The 873-973 K was found to be the optimum range of temperature, under the high pressure (30 bar) conditions, for the production of H2 of purity exceeding 85%. The developed model of SE-SMR was validated against the literature data. The mathematical model of SE-CLSR process was developed under adiabatic conditions. This model is the combination of reduction of catalyst followed by oxidation of the reduced catalyst. The individual models of reduction and oxidation are developed by using kinetic data available in the literature and later on validated with experimental results proposed in the literature. The already developed model of SE-SMR process is combined with the OTM reduction model to mimic the dynamic process occurring in the fuel reactor (FR) system. This FR is combined with air reactor (AR) and the combined model is run for 10 cycles. The sensitivity of the process is studied under the various operating conditions of temperature (873-1023 K), pressure (1-30 bar), molar S/C (2-6) and mass flux of the gas phase (Gs = 2-7 kg m-2 s-1). In this work, the operating conditions used for the production of H2 represent realistic industrial production conditions. The sensitivity analysis demonstrates that the developed model of SE-CLSR process has the flexibility to simulate a wide range of operating conditions of temperature, pressure, S/C and Gs.
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Bargheer, Matias. "Ultrafast photodynamics in condensed phase ClF, Cl2 and I2 in solid rare gases /." [S.l. : s.n.], 2002. http://www.diss.fu-berlin.de/2002/206/index.html.
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Kerouedan, Sylvie. "Conception et réalisation de circuits VLSI-CLF pour le traitement de l'information optique." Brest, 1998. http://www.theses.fr/1998BRES2012.
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Le contexte de cette these est l'etude de circuits integres optoelectroniques sur substrat silicium interfacant entrees optiques (photodiodes) et sorties optiques (cristal liquide ferroelectrique). Pour valider les relations entre les composants optiques et les fonctions electroniques integrees, deux circuits ont ete realises. La premiere realisation, un aiguilleur optique a adressage integre met en evidence la relation circuit integre et clf, en particulier elle montre les difficultes technologiques du depot de clf sur ci. Cette application de routage electronique entre fibres optiques monomodes permet d'envisager l'integration sur un meme support, le silicium, de la fonction d'adressage et des miroirs optiques. Ces miroirs assurent la creation de chemins optiquement transparents et reconfigurables entre 2 fibres quelconques. La deuxieme realisation, une retine de detection de contours permet d'illustrer les problemes d'interconnexions dans les systemes a base de pixels fortement interconnectes. Elle montre egalement que le choix de l'algorithme s'avere tres important : sa complexite entrainera un rapport surface photosensible par pixel/surface totale du pixel plus ou moins convenable dans des applications de traitements d'images. A la suite de ces realisations, nous cherchons a donner quelques pistes de reflexion pour repondre a quelques questions sur les traitements optoelectroniques complexes : comment peut-on les implanter sur silicium ? quand est-il preferable d'effectuer des operations optiques plutot que des operations electroniques ? quels sont les avantages des systemes d'interconnexions optiques ?
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Busolin, Giorgia. "Transcriptional reprogramming of muscle fibers by chronic electrical stimulation." Doctoral thesis, Università degli studi di Padova, 2013. http://hdl.handle.net/11577/3423414.
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Background: Skeletal muscle fibers have a remarkable capacity to adjust their molecular, functional, and metabolic properties in response to developmental and environmental stimuli. A central role for neuromuscular activity in determining skeletal muscle fibers composition was demonstrated by cross-innervation and electrical stimulation experiments in adult skeletal muscle. A fast to slow transition can be induced by chronic low-frequency electrical stimulation (CLFS). In literature, CLFS studies have focused on the effects produced after days or weeks of stimulation. Here, I present the first transcriptome study that identifies the earliest genetic changes in this process.
Methods: The fast EDL muscle was subjected to CLFS for 6 and 12 hours. First, microarray experiments were performed using whole EDL muscle. Then, in order to reduce biological noise caused by different cell types, I applied microgenomic analyses at the level of single fibers (SF), isolated according to the protocol recently developed in my laboratory. Microarray experiments have been produced with updated platforms (Agilent SurePrint G3 Mouse GE 8x60K).
Results and discussion: The expression profiles of whole muscle after 6 and 12 hours of electrical stimulation identified about two hundred differentially expressed (DE) genes. The functional categories of blood vessel development and transcription regulation were most enriched. Genomic analyses of isolated fibers identified more than a thousand DE genes after 12 hours of stimulation. The functional category of blood vessel development was enriched also at the SF level, suggesting that myofibers are able to interact with other cell types in order to stimulate the angiogenesis process. In general, muscle structural genes were equally expressed between stimulated and unstimulated muscles, indicating that changes in fiber type require prolonged stimulation. On the contrary, genes involved in transcription, chromatin-remodeling genes and several myofibril genes acting as signaling molecule were early activated after CLFS.Introduzione: Le fibre del muscolo scheletrico possiedono una notevole capacità di modificare le loro proprietà molecolari, funzionali e metaboliche in risposta a stimoli di crescita e ambientali. Esperimenti di cross-innervazione e stimolazione elettrica hanno dimostrato il ruolo fondamentale dell’attività neuromuscolare nel determinare il tipo di fibra. La stimolazione cronica a bassa frequenza (CLFS) è in grado di indurre il processo di trasformazione di una fibra veloce verso un fenotipo lento. Fino ad ora, questi processi sono stati studiati dopo lunghi periodi di stimolazione. In questo lavoro, mi sono proposta di identificare i cambiamenti trascrizionali precoci di questo processo. Metodi: Il muscolo veloce EDL di topo è stato sottoposto a CLFS per 6 e 12 ore. Inizialmente ho utilizzato il muscolo intero per produrre i profili di espressione Successivamente, per ovviare al problema dell’eterogenea composizione del muscolo, ho utilizzato l’approccio microgenomico, producendo profili di espressione a livello di una singola fibra, isolata utilizzando il protocollo sviluppato nel mio laboratorio. Tutti i profili sono stati ottenuti mediante l’utilizzo di piattaforme Agilent (SurePrint G3 Mouse GE 8x60K). Risultati e discussione: I profili di espressione con il muscolo intero hanno identificato circa 200 geni differenzialmente espressi (DE). Lo sviluppo dei vasi sanguigni e la regolazione della trascrizione sono risultate le categorie funzionali più arricchite. Le analisi genomiche a livello di singola fibra hanno identificato più di mille geni DE dopo 12 ore di stimolazione. La categoria funzionale riguardante lo sviluppo dei vasi sanguigni risulta arricchita anche con questo approccio, suggerendo un’interazione tra le fibre muscolari e gli altri tipi cellulari al fine di stimolare il processo di angiogenesi. La maggiorparte dei geni strutturali risulta essere ugualmente espressa, suggerendo che i cambiamenti nel tipo di fibra richiedono un tempo prolungato. Al contrario, i geni coinvolti nella trascrizione, nel rimodellamento della cromatina e alcuni geni miofibrillari che agiscono come molecule di segnale, si attivano rapidamente in risposta a CLFS.
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Qureshi, Karl. "Att maskinöversätta sökfrågor : En studie av Google Translate och Bing Translators förmåga att översätta svenska sammansättningar i ett CLIR-perspektiv." Thesis, Umeå universitet, Sociologiska institutionen, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-131813.
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Syftet med denna uppsats är att undersöka hur väl Google Translate respektive Bing Translator fungerar vid översättning av sökfrågor med avseende på svenska sammansättningar, samt försöka utröna huruvida det finns något samband mellan utfallet och sammansättningarnas komplexitet. Testmiljön utgörs av Europaparlamentets offentliga dokumentregister. Undersökningen är emellertid begränsad till Europeiska rådets handlingar, som till antalet är 1 334 på svenska respektive 1 368 på engelska. Analysen av data har dels skett utifrån precision och återvinningsgrad, dels utifrån en kontrastiv analys för att kunna ge en mer enhetlig bild på det undersökta fenomenet. Resultatet visar att medelvärdet varierar mellan 0,287 och 0,506 för precision samt 0,400 och 0,614 för återvinningsgrad beroende på ordtyp och översättningstjänst. Vidare visar resultatet att det inte tycks finnas något tydligt samband mellan effektivitet och sammansättningarnas komplexitet. I stället tycks de lägre värdena bero på synonymi, och då gärna inom själva sammansättningen, samt hyponymi. I det senare fallet beror det dels på översättningstjänsternas oförmåga att återge lämpliga översättningar, dels på det engelska språkets tendens att bilda sammansättningar med lösa substantivattribut.
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PEREIRA, P. M. "DESEMPENHO DE PLANTAS DE Jatropha curcas L. CULTIVADAS EM DUAS LOCALIDADES DO ESTADO DO ESPÍRITO SANTO." Universidade Federal do Espírito Santo, 2014. http://repositorio.ufes.br/handle/10/10014.
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Previous issue date: 2014-01-23RESUMO O objetivo desse estudo foi avaliar o desempenho das plantas de pinhão-manso (Jatropha curcas L.) cultivadas em duas localidades do estado do Espírito Santo: Itarana e Pontal do Ipiranga. Para isso, foram realizadas medições entre dezembro de 2012 a abril de 2013 quanto à fenologia vegetativa e reprodutiva, trocas gasosas, fluorescência transiente e modulada da clorofila a e índice de clorofila. No período de avaliação os maiores picos de floração ocorreram entre o mês de dezembro e janeiro nas plantas cultivadas em Itarana e o maior número de frutos secos foram encontrados no mês de março. As plantas cultivadas em Pontal do Ipiranga mostraram menor crescimento de parte aérea e baixa produção de inflorescências, flores e frutos. Houve queda das folhas mais velhas durante o período de maior estresse hídrico e rebrota logo após as primeiras chuvas na região de Pontal do Ipiranga enquanto na região de Itarana não houve perda de folhas durante o período analisado. As trocas gasosas mostraram as maiores taxas, em Itarana, no início do período reprodutivo e queda gradativa ao longo dos meses enquanto na região de Pontal do Ipiranga ocorreu o inverso e as maiores taxas de fotossíntese líquida aconteceram ao final do período de frutificação. A análise da diferença cinética (ΔVOP) apontam diferenças positivas nas folhas das plantas cultivadas em Pontal do Ipiranga, que demonstram claramente a inibição do transporte de elétrons entre o FSII e o FSI nos três primeiros meses analisados (dezembro, janeiro e fevereiro). Observou-se o aparecimento de banda K, indicativa de danos no processo de fotoxidação da água no complexo de evolução do oxigênio, diminuição da conectividade das unidades que compõem o centro de reação do FSII, comprovado pelo aparecimento da Banda L positiva e uma banda G positiva indicativa de danos ao nível de pool de plastoquinonas e comprometimento da eficiência do FSI nas plantas de Pontal do Ipiranga entre os meses de janeiro, fevereiro e março. Considerando que o desenvolvimento da cultura é afetada pelos níveis de radiação fotossinteticamente ativa, pela sazonalidade da temperatura e da pluviosidade torna-se necessário considerar as variáveis fisiológicas durante a elaboração de modelos de zoneamento agroclimático. Infere-se, portanto, que as plantas que possuíram melhor desempenho da cultura foram as plantas cultivadas na localidade de Itarana. Palavras-chave: Jatropha curcas L., floração, índice de clorofila, trocas gasosas e fluorescência da clorofila a.
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Hellriegel, Ronald. "Ätzen von Titannitrid mit Halogenverbindungen." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2009. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1245418105568-70747.
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Mit zunehmender Miniaturisierung mikroelektronischer Bauelemente steigen die Anforderungen an reproduzierbare qualitätskonforme Schichten. Um die zur Herstellung notwendigen ALD/PVD/CVD-Schichtabscheideanlagen in einen zuverlässigen Zustand zu versetzen, ist eine regelmäßige Kammerreinigung notwendig. Während des Abscheideprozesses werden nicht nur das Substrat, sondern auch die umliegenden Kammerteile beschichtet. Diese Schichten wachsen mit jedem Beschichtungszyklus weiter an. Der Stress zwischen Schicht und Kammerwand steigt beständig, und es besteht das Risiko das Teile abplatzen und auf die Waferoberfläche fallen und damit die Struktur unbrauchbar machen. Um das zu verhindern, muss die Kammerwand in einen regelmäßigen Zustand versetzt werden, in dem sichergestellt ist, daß keine Schichtreste abplatzen können. In der vorliegenden Arbeit wird ein neues Verfahren zur Trockenreinigung von ALD-Titannitrid Kammern vorgestellt. Dazu wurden TiN-Stücke (hergestellt im ALD, CVD, PVD-Verfahren) auf einem temperaturgeregelten Probenhalter platziert. Eine Argon/NF3 Gasmischung wurde in einer externen Plasmaquelle (RPS) zerlegt und in die Reaktionskammer geschleust. Die Ätzung wurde mit in-situ Reflexionsmessung beobachtet. Experimente mit Chlorzugabe wurden unternommen und ein starker Einfluss auf den Ätzmechanismus beobachtet. Die Ätzraten des TiN sind exponentiell abhängig von der Temperatur und proportional abhängig von der Verfügbarkeit atomaren Fluors. Dieses wird bei der Zerlegung von NF3 frei gesetzt und steht der Reaktion zur Verfügung. Die NF3-Zerlegung in Fluor und Stickstoff wurde mit Hilfe der Massenspektrometrie (QMS) untersucht, Zerlegungsgrade größer 96% wurden erreicht. Mit Hilfe dieser Messung kann der Einfluss der Kammerreinigung auf den Treibhausgasausstoß (GWP) bestimmt werden. Mit dem Ar/NF3-Verfahren können die GWP-Emissionen um 90% im Vergleich zur RIE-Ätzung mit SF6 reduziert werden. Mit Argon/Chlor-Plasmen konnte kein Titannitrid geätzt werden, da die physikalische Sputterkomponente fehlte. Durch Hinzufügen von Chlor zu einer Ar/NF3-Gasmischung konnte die Ätzrate um bis zu 270% im Bereich niedrige Temperaturen/niedriger Druck gesteigert werden. Bei höheren Temperaturen/höherem Druck fielen die Ar/NF3/Chlor Ätzraten allerdings deutlich hinter die des Ar/NF3 zurück. Die dazu führenden Effekte werden untersucht und ausgeführt. Die Nutzung von externen Plasmaquellen bietet eine vielversprechende Alternative um Abscheideanlagen von TiN-Rückständen reinigen zu können. Bei hohen Temperaturen werden deutlich höhere Ätzraten als bei anderen Schichten (SiN, SiO2, W) erreicht. Für Anwendungen im niedrigen Temperaturbereich erlaubt die Zugabe von Chlor interessante AnwendungsmöglichkeitenDemands on state of the art deposition technologies for semiconductor production focus on uniformity, repeatability and low defectivity. The chamber condition is a key parameter to achieve these high demands in chemical vapour deposition (CVD) processes and are even more critical to the atomic layer deposition processes (ALD). During the deposition process not only the wafer surface but other chamber parts as well are covered with a thin film. This film accumulates during the deposition cycles and is prone to fall off the walls and pollute the wafer surface. The chamber parts that are exposed to the deposition must be set back to a steady state so that no deposits fall off the walls. The chamber condition also changes uncontrolled with varying film condition on the wall. A new approach for cleaning of ALD-titanium nitride (TiN) deposition chambers was investigated. To determine etch rates TiN-samples (created by ALD, CVD and PVD) were placed on a temperature controlled sample holder. An argon/NF3 mixture was excited in an upstream remote plasma source (RPS) and then routed through the reaction chamber. No further plasma activation inside the reaction chamber was done. The etching was monitored by in-situ reflectometry and etch rates were calculated. The effect of chlorine addition was also studied and strong influence on etch rates was found. The etch rate of TiN is dependent exponentially on temperature and very low etch rates were achieved below 70◦C at a chamber pressure ranging from 20-300 Pa. It was found that this correlates very well with the vapour pressure of the reaction product TiF4. At temperatures of 300◦C etch rates up to 800 nm/min were achieved. The optimum pressure for etching was found at 100 Pa while the pressure effect was small. The etch rate was mainly dependent on the availability of activated fluorine to create TiF4 by the reaction 2 NF3 → N2 + 6 F* 2 TiN + 8 F* → 2 TiF4 + N2 The NF3 decomposition to nitrogen and fluorine was monitored by quadrupole mass spectrometry (QMS) and was found to be greater than 96%. This figure allows an estimation of the amount of Global warm potential (GWP) gas emmited by the process for environmental considerations. Using argon/NF3 or argon/fluorine mixtures in RPS devices reduces the GWP emissions by more than 90% compared to RIE plasma cleaning with SF6. No etching occurred by using argon/chlorine only mixtures as no physical etch component was involved in RPS etch. However adding chlorine to the argon/NF3 mixture accelerated the etching process. Chlorine addition to the argon/NF3 mixture increased the etch rates up to 270% in the low pressure/low temperature regime. At higher temperatures or higher pressures the etch rates dropped below the etch rates achieved solely with fluorine chemistry. It must be emphasized that there is no physical acceleration of the ionized molecules toward the etched sample in this remote plasma setup. The usage of a remote plasma offers an alternative way to remove residues from chambers running TiN deposition processes. At high temperatures the Ar/NF3 offers remarkably high etching rates for TiN compared to other films (silicon nitride, -oxide, tungsten) usually cleaned by remote plasma. For low temperature applications the chlorine enhancement offers an interesting alternative to accelerate the etch process
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Güldogus, Melih. "Proof of Concept of Closed Loop Re-Simulation (CLR) Methods in Verification of Autonomous Vehicles." Thesis, KTH, Reglerteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-223978.
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This degree project, conducted at Volvo Cars, investigates whether closed-loopre-simulation (CLR) methods can provide a safety proof for the autonomousdriving (AD) functions based on previously collected driving data. The elementsunder study for this closed loop approach are model-in-loop based SimulationPlatform Active Safety (SPAS) environment and Active Safety (AS)software.The prerequisites for securing the closed loop re-simulation environment areperforming open-loop simulations with AS software under test and preparing avalidated vehicle model constituting the sensors and actuators. The validatedvehicle model against a set of physical data ensures high confidence in the CAEenvironment. This results in high correlation between physical and simulateddata for the closed loop tests performed for testing the Active Safety algorithms.This thesis work focuses on preparing the vehicle model in SPAS with the emphasison performance of auto-brake functionality in CLR. The vehicle modelin SPAS was prepared by tuning the brake model focusing on the EuNCAPcases in which CLR environment was subsequently tested with respect to Eu-NCAP scenarios.In the procedure of securing CLR methods, it was crucial to design the scenariosin virtual test environment as close as possible to field test conditions tomake reliable comparison with the reality. Therefore, the verification of CLRenvironment was carried out by subjecting the CAE Environment to EuNCAPbraking scenarios with dry surfaces, host vehicle velocities up to 80 km/h andtarget vehicle deceleration levels being 2m/s2 and 6m/s2.As a result of all these virtual tests, it was empirically verified that CLR environmentcan be used to predict braking behaviour of the vehicle in certaintraffic scenarios for the verification of autonomous driving functions.I detta examensarbete, som utförs på Volvo Cars, undersöks hurvida ett closedloopre-simuleringsverktyg kan användas för att bevisa att en självkörande(AD) funktionalitet är säker baserat på tidigare insamlad kördata. Dennastudie involverar användandet av ett Model-in-the-loop baserat simuleringsverktygkallat Simulation Platform for Active Safety (SPAS) och en mjukvara förAktiv Säkerhet (AS).Förutsättningarna för att säkra en closed-loop re-simuleringsmiljö är att mjukvaransexekvering och fordonsmodellen i simuleringsmiljön valideras genomopen-loop tester. Den valididerade fordonsmodellen jämförs med data frånfysiska prover för att säkra hög konfidens i simuleringarna.Detta examensarbete fokuserar på att förbereda fordonsmodellen i SPAS medtryck på prestandan av auto-broms systemet. Fordonsmodellen i SPAS beredesgenom att ställa in bromsmodellen med fokus på EuNCAP lastfall där CLRmiljön skulle tillämpas. I processen att säkra CLR metoden var det viktigt attdesigna testfall i den virtuella miljön som så bra som möjligt matcha fältprovsfall för att kunna göra en trovärdig jämförelse, därav användes EuNCAP bromstestfall vid torrt underlag, ego hastighet upp mot 80km/h och målbilshasdeccelerationmellan 2 m/s2 och 6 m/s2Som ett resultat av dessa virtuella test har det empiriskt verifierat att CLRmetoden kan användas för att förutspå broms prestanda av fordonet i specifikatrafikscenarion för självkörande funktionalitet.
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Rutkowski, Emilia [Verfasser], Harald [Akademischer Betreuer] Kolmar, and Alexander [Akademischer Betreuer] Steinle. "Erstcharakterisierung des C‐Typ Lektin‐ähnlichen Glykoproteins Clr‐a / Emilia Rutkowski ; Harald Kolmar, Alexander Steinle." Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2019. http://d-nb.info/1199006319/34.
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MORESCALCHI, LUCA. "Study of the calorimetric detection of the muon to electron conversion in the Mu2e experiment." Doctoral thesis, Università di Siena, 2017. http://hdl.handle.net/11365/1030437.
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The Mu2e experiment will search for Charged Lepton Flavor Violation (CLFV), looking at the coherent conversion of a muon into an electron in the field of an aluminum nucleus. The knowledge of such a CLFV reaction allows to indirectly probe new physics at energy scales up to thousands of TeV, inaccessible with direct searches at either present or planned high energy colliders. For this reason, Mu2e will measure the muon-to-electron conversion rate R_{\mu e} with an unprecedented accuracy, so to improve of a factor 10^4 the best current measurement and, in case of no observation, to constrain its value below 6 x 10^-17 at 90% of CL. To reach this ambitious sensitivity, about 10^18 muonic atom decays have to be observed: Mu2e is expected to use an intense pulsed muon beam, and rely on a detector system composed of a straw tube tracker and an electromagnetic calorimeter. The calorimeter is composed of 1348 un-doped CsI crystals, each coupled to two large area Silicon Photomultipliers (SiPMs). It plays a central role in the Mu2e measurement, providing particle identification capabilities that are necessary to reject the cosmic muons and antiprotons induced background. Moreover, the calorimeter has to help the tracker providing a seed for the pattern recognition and to provide a fast independ trigger. Having these experimental requests as pivotal reference, a set of Quality Assurance (QA) criteria for the calorimeter active components have been defined. Following the corresponding QA procedures, a first batch of crystals and photosensors has been characterized and used to assemble a medium scale prototype of the calorimeter (Module-0). The Module-0 has been studied by means of a 100 MeV electron beam, confirming that expected calorimeter performances well satisfy the Mu2e requirements.
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Mutlu, Alper. "Increasing Clavulanic Acid Production Both In Wild Type And Industrial Streptomyces Clavuligerus Strains By Amplification Of Positive Regulator Clar Gene." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614797/index.pdf.
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Streptomyces clavuligerus is a Gram-positive, filamentous bacterium which produces several important secondary metabolites, including isopenicillin N, cephamycin C and the &beta-lactamase inhibitor clavulanic acid. Among these compounds, clavulanic acid is being used in combination with commonly used &beta
-lactam antibiotics in order to fight against bacterial infections that are resistant to such antibiotics. Among these combinations, Augmentin, composed of amoxicillin and clavulanic acid, is the most widely prescribed drug and has a market value of more than one billion dollars per year. There are two genes that act in regulation of clavulanic acid biosynthesis: ccaR located in cephamycin C gene cluster and claR located in clavulanic acid gene cluster. The goal of this study is to improve clavulanic acid production capacities of both wild type and industrial S. clavuligerus strains by integrating extra copies of claR gene into S.clavuligerus genome and its overexpression via a multicopy plasmid. Although previously has shown to be quite effective on wild type S. clavuligerus strains, claR overexpression in the industrial strain used in this study yielded only 1.4-fold increase in volumetric and 1.7-fold increase in specific CA production by the recombinant strains MA28 and MA16, respectively.
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Clar, Cristin Carmen [Verfasser], and Jan [Akademischer Betreuer] Born. "Die Auswirkung von Schlaf auf das emotionale Gedächtnis bei Schulkindern - und die Reaktion der Herzfrequenz / Cristin Carmen Clar ; Betreuer: Jan Born." Tübingen : Universitätsbibliothek Tübingen, 2019. http://d-nb.info/1199929840/34.
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Varichon, Anne. "Couleur et nuancier, territoires et fonctions : analyse poïétique de l'échantillonnage de la couleur par les manufactures, l'industrie et le commerce." Thesis, Toulouse 2, 2011. http://www.theses.fr/2011TOU20129.
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La couleur est omniprésente dans nos quotidiens, mais sa représentation par le marketing fait apparaître aujourd’hui un double paradoxe : d’une part le recours à une rhétorique publicitaire invoquant des caractéristiques de la couleur qui sont précisément niées par sa fabrication industrielle, et d’autre part, la multiplication de l’image du nuancier dans des conditions d’impression qui s’opposent aux fonctions d’exemplification qu’il est sensé assumer. Cette thèse se propose de mettre en évidence, grâce aux outils de la poïétique, les mutations qu’a connu la construction de la pensée de la couleur par les manufactures, l’industrie et le commerce depuis le milieu du XIXème siècle en interrogeant ses divers modes d’échantillonnage, le nuancier notamment, tels qu’ils ont été instaurés par ses producteurs. Mais l’échantillonnage de la couleur est ici envisagé comme une interface d’expression maximum entre les producteurs et commerçants de couleur et ceux auxquels il est destiné : il relève de conduites créatrices spécifiques, il en génère aussi.L’objectif de ce travail est de parvenir à mesurer l’évolution respective des divers types d’information apportés, et donc communiqués, par le nuancier. La recherche s’ancre dans un corpus de documents sur lequel est appliqué une grilled’analyse permettant dans un premier temps de mettre en évidence les cinq territoires d’information qui ont été identifiés dans l’échantillonnage de la couleur, puis d’en explorer les caractéristiques quantitatives et qualitatives. Des concepts opératoires ont ainsi pu être élaborés pour cerner précisément deux conduites créatives distinctes : celle générant le nuancier et celle générant le recueil d’échantillons. L’amplitude chronologique de cette recherche ainsi que le parti-pris de laisser au terrain la possibilité de déployer toute sa richesse a imposé ses limites à l’entreprise. Celle-ci devait poser le cadre et les principaux repères d’un sujet encore peu exploré et élaborer des outils conceptuels aptes à être réutilisés. Une évaluation de la pertinence de la méthode, des outils et des concepts mis en oeuvre a été effectuée. Ses résultats sont encourageants puisqu’ils montrent que la recherche entreprise est féconde pour déceler les enjeux dont le nuancier, entre industrie et individu, est partie prenante. Elle a mis en évidence que l’analyse du nuancier, entité riche de ce dont elle résulte et de ce qu’elle induit, peut être employée pour contribuer à décrypter la société contemporaine. Il s’agira de prolonger cette première étape par de nouvelles investigations sur l’échantillonnage de la couleurColour is omnipresent in our daily lives, but its representation in today’s marketing shows a double paradox: on the one hand, the use of advertising rhetoric, invoking characteristics of color – the same being manifestly denied by the manufacturing industry, and on the other hand, the multiplication of the image of color chart – but under printing-conditions that are opposed to the functions of exemplification it is supposed to fulfill. Using tools from poietic, this thesis intends to demonstrate what kind of changes manufacturers, industry and commerce has gone through in terms of construction of theidea of colour since the mid-nineteenth Century by questioning its various sampling modes, in particular how the color chart was introduced by manufacturers. Sampling of colour is here considered as an interface of maximum expression betweencolour producers and traders and those for whom it is intended: it originates from specific creative conducts - which it also generates. The purpose of this work is to measure the evolution of each type of provided - and obviously communicated - information through the color chart. The research is anchored to a body of documentation, upon which an analytical grid isapplied, first of all in order to define the five fields of information the colour sampling has allowed for. It also enables one to explore their quantitative and qualitative characteristics. Thus it has been possible to develop operational concepts in order to define precisely two distinct creative lines: one generating the color chart and the other generating the sample collection. The chronological amplitude of this research and the prejudice to let the field maintain its ability to display all its treasures, has imposed its own limitations to this research. It has defined the framework and the main landmarks of a - until now - poorly explored subject and developed the conceptual tools capable of being re-used. An evaluation has been performed on the adequacy of the methodology, the tools and on implemented concepts. The results are encouraging as they show that the undertaken research has successfully identified the issues the color chart, the rich entity of where it comes from and what it leads to can contribute to deciphering contemporary society. The purpose is to extend this first step by carrying out new investigations on the sampling of color
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Didak, Blanka. "Synthèse de néoglycoconjugués et dendrimères glycomimétiques utilisés pour le développement de puces à lectines de type C et leur validation." Thesis, Université Grenoble Alpes (ComUE), 2018. http://www.theses.fr/2018GREAV036.
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Les lectines de type-C (CLR) sont des protéines de liaison au glycane qui reconnaissent les sucres de manière dépendante du Ca2+. Ils ont des rôles divers dans l'organisme humain. Ils sont responsables des interactions et de l'internalisation d'agents pathogènes tels que Candida albicans, Mycobacterium tuberculosis, le VIH ou le virus Ebola. Ils sont également impliqués dans le développement ou la prévention du cancer par la reconnaissance de glycanes spécifiques exprimés à la surface des cellules tumorales.L'importance cruciale est de trouver des ligands pour les CLR qui induiront une réponse immunitaire ou des inhibiteurs pour les lectines impliquées dans la promotion des infections dans l'organisme. L'objectif du réseau IMMUNOSHAPE était d'examiner de près les rôles, les spécificités et les différences entre les CLR et d'essayer de trouver des molécules appropriées pour stimuler la réponse immunitaire. Au cours de cette thèse, les néoglycoprotéines (NGP) contenant des glycodendrons de différentes valences ont été synthétisées. Pour la synthèse ont été utilisés BSA et OVA comme porteurs de protéines sur lesquels sont couplés des composés monovalents et des dendrons avec αMan et Manα1-2Man de trois et neuf valences. Tous les NGP ont été synthétisés par la chimie click avec deux équivalents de glycodendron / BSA. De plus, des NGP avec des glycomimétiques sur la base de fucose et de Manα1-2Man ont été préparés.L'affinité des molécules synthétisées a été analysée avec GLYcoPROFILE, la plateforme technologique développée par GLYcoDiag dans le but de mieux étudier les interactions glycobiologiques. Il a été évalué que tous les composés testés présentaient un effet multivalent fort sur quatre lectines spécifiques du mannose, y compris deux CLR : DC-SIGN et Langerin. La néoglycoprotéine avec 11 dendrons Manaαl-2 Man nonavalés a obtenu la meilleure avidité pour toutes les lectines testées. Les IC50 obtenues pour la Langerine et le DC-SIGN sont respectivement de l’ordre du nanomolaire et picomolaire, c’est une des valeurs les plus faibles obtenues pour ces deux lectines.L'étude des interactions glycobiologiques a été élargie par l'analyse des différences entre les glycanes avec les liaisons O, C et S et leurs interactions avec les lectines. Il a été observé que les C-glycanes n'ont pas le même mode de liaison que les O-glycanes et, par la suite, ne présentent pas le même effet multivalent attendu, que les O-glycanes. Dans le contexte des glycosides, nous montrons que l’O-glucoside présente de meilleures interactions avec les lectines purifiées que le S-glucoside, tandis que le S-galactoside offre une inhibition significativement meilleure entre les kératinocytes humains normaux et les néoglycoprotéines correspondantes. En outre, une étude intéressante a porté sur les interactions entre les thio-sialosides et la sialidase NanA. Cette analyse a montré que la multivalence a un effet important non seulement sur la lectine, mais également sur la liaison de l’enzyme. Les NGP synthétiques thio-sialylés ont mis en évidence un inhibiteur multivalent efficace de l'enzyme NanA.Au final, cette thèse présente des résultats intéressants sur l'influence significative des composés multivalents sur les interactions glycobiologiques entre les glycanes et les lectines ainsi que sur les enzymes. Cette connaissance pourrait être utilisée dans la conception future des vaccins et de leurs adjuvants pour le traitement des infections,du cancer et, en général, pour la formation de la réponse immunitaireC-type lectins (CLRs) are glycan binding proteins which recognize sugars in Ca2+ dependent manner. They have diverse roles in human organism. They are responsible for interactions and internalization of pathogens like Candida albicans, Mycobacterium tuberculosis, HIV or Ebola virus. They are also involved in development or prevention of cancer through recognition of specific glycans expressed on surface of tumor cells.The crucial importance is to find ligands for CLRs which will induce immune response or inhibitors for lectins which are involved in promotion of infections in organism. The goal of IMMUNOSHAPE network was to closely examine roles, specificities and differences between CLRs and try to find appropriate molecules for driving immune response. During this thesis, neoglycoproteins (NGPs) containing glycodendrons with different valences were synthetized. For synthesis were used BSA and OVA as protein carriers on which are coupled monovalent compounds and dendrons with αMan and Manα1-2Man in three and nine valences. All NGPs were synthetized with click chemistry with two ratios of glycodendron/BSA. Additionally, NGPs with glycomimetics on the basis of fucose and Manα1-2Man were prepared.The affinity of synthetized molecules was analyzed with GLYcoPROFILE, technology platform developed in GLYcoDiag with the aim of better and more precise investigation of glycobiological interactions. It was evaluated that all tested compounds showed strong multivalent effect on four mannose specific lectins, including two CLRs: DC-SIGN and Langerin. Neoglycoprotein with 11 nonavalent Manα1-2Man dendrons achieved the best avidity for all tested lectins. Obtained IC50 for Langerin and DC-SIGN are of nanomolar and picomolar range respectively, which are one of the lowest values obtained for these two lectins.Studying glycobiological interactions was expanded by analysis of differences between glycans with O-, C- and S-linkage and their interactions with lectins. It was observed that C-glycans does not have the same mode of binding like O-glycans and subsequently, do not show the same expected multivalent effect such as O-glycans. In the context of glycosides, we show that even O-glucoside achieved slithly better interactions with purified lectins in comparison with S-glucoside, S-galactoside provide significantly better inhibition between normal human keratinocytes and corresponding neoglycoproteins in comparison with O-galactoside. Furthermore, interesting study was investigation of interactions between thio-sialosides and sialidase NanA. This analysis showed that multivalency has a strong effect not only on lectin, but also on enzyme binding. Synthetized thio-sialylated NGPs showed as efficient, multivalent inhibitor of NanA enzyme.Altogether, this thesis presents interesting results of significant influence of multivalent compounds on glycobiological interactions between glycans and lectins as well as enzymes. This knowledge could be used in future design of vaccines and their adjuvants for infection and cancer treatment and in general, for shaping immune response
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Loaiza, Flores Juan Isidro. "El Comité Local de Asignación de Recursos - CLAR en la Región Arequipa, como modelo de asignación y vigilancia de los recursos públicos." Master's thesis, Pontificia Universidad Católica del Perú, 2013. http://tesis.pucp.edu.pe/repositorio/handle/123456789/5514.
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El presente trabajo de investigación, que sirve de base para optar el grado de magister en Gerencia Social recoge la experiencia del Proyecto Sierra Sur, en la implementación de los Comités Locales de Asignación de Recursos – CLAR, tomando diversas fuentes y actores directos de intervención.
El Proyecto Sierra Sur, que es financiado por el Estado Peruano y el FIDA, ha implementado Los Comités Locales de Asignación de Recursos - CLAR, son instancias que están integradas por representantes de la sociedad civil, cuya función principal es la de evaluar las propuestas presentadas por las organizaciones locales que concursan para acceder a fondos públicos que ofrece el proyecto, con la finalidad de ejecutar sus planes de negocio o de manejo de recursos naturales.
Esta es una expresión de la democratización del estado y la participación ciudadana, que si bien es cierto no es una práctica generaliza, es un primer intento a nivel de proyectos que bien puede ser una alternativa que se perfeccione y se adecue para ser generalizada y contribuya al proceso de democratización y la participación ciudadana como lo menciona Remy.
El objetivo principal de la presente investigación es conocer el modelo de asignación de recursos económicos públicos para el cofinanciamiento de iniciativas productivas, mediante los concursos públicos ante el Comité Local de Asignación de Recursos CLAR que aplica el Proyecto Sierra Sur, en la Oficina Local de Chivay – Arequipa.
El propósito es contribuir a que se conozcan los mecanismos utilizados por el CLAR, que muestran la transparencia en la asignación y vigilancia de los recursos económicos públicos, así como identificar cuáles han sido los logros y dificultades del CLAR.
La metodología que se utilizó es de carácter cualitativo, empleado para el recojo de la información una guía de entrevistas, una ficha de observación y la revisión documentaria del proyecto. Los resultados muestran las apreciaciones, opiniones, juicios y expectativas, de integrantes del proyecto, diseñadores de los proyectos FIDA, población usuaria del proyecto y miembros del CLAR, sobre los mecanismos que utiliza el CLAR.Tesis
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Abou, Samra Elias. "Elucidation of the Role of NKR‐P1: CLR Recognition Systems in Intestinal & Renal Epithelial Cell Homeostasis and Immunity." Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/35747.
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Natural killer (NK) cells represent a crucial component of the innate immune system and are primarily regulated by the interactions of their activation and inhibitory receptors with ligands available on target cells. The genetically linked Ly49 and NKR-P1 family of receptors constitute two of the major regulatory receptor systems used by NK cells and have been shown to bind different ligands. Whereas the Ly49 receptors survey MHC-I ligands on target cells, the NKR-Pl receptor family members bind to various members of the C-type lectin-related (Clr) family. Interestingly, NKR-P1 and Clr haplotypes possess a stable genomic polymorphism across multiple mouse strains, suggesting that this inhibitory receptor:ligand relationship has an important role in the maintenance of host cellular cognate specificities. The NKR-P1 and Clr receptor-ligand pairs identified in mice include the NKR-P1B:Clr-b and the NKR-P1G:Clr-f interacting pairs. Previous RT-PCR and in situ RNA hybridization data generated by our laboratory determined that kidney tubular epithelium as well as the small and large intestinal epithelial cells specifically and highly expresses the Clr-f transcripts. Contrarily, the Clr-b transcripts were only detected on hematopoietic cells of various lymphoid organs and kidneys. Moreover, foregoing studies revealed that the loss of Clr-b following viral or chemical induced stress mediates NK cell killing of the target cell, suggesting a tissue-specific immune-surveillance mechanism in parallel with the global MHC-I-dependent missing-self model. However, the role of the NKR-P1B:Clr-b recognition-system have never been examined in the intestine. Additionally, the role of Clr-f in the kidney and intestines, where they are highly expressed, has not been investigated. For these reasons, I aimed in my thesis to provide a better understanding of the functional aspect of the NKR-P1B:Clr-b and NKR-P1G:Clr-f recognition systems in mediating gut mucosal and renal homeostasis, respectively.
First, in order to determine the role of NKR-P1B and Clrb receptor:ligand pair as a “missing-self” immunosurveillance system in the gut, I started by identifying the expression pattern of both the receptor and ligand on various intestinal cells. My results demonstrate that NK cells do not represent the major NKR-P1B-expressing cells in the gut lamina propria. Instead, ILC3 subsets constituted the predominant cell population expressing the receptor, whereas γδT cells composed a small fraction of NKR-P1B+ lymphocytes. In addition, the NKR-P1B expression on myeloid cells was exclusive to colon macrophages and DC subsets. Interestingly, the highest percentage of NKR-P1B+ immune cells was found in the gut, which suggests the dominant role of NKR-P1B in regulating immune functions at the level of intestinal mucosa. As expected, the expression of the NKR-P1B ligand, Clr-b, appeared on all innate immune cell types in the gut. Next, using oral infection models of Salmonela typhimurium and Citrobacter rodentium, I showed that NKR-P1B-deficient NK cells, ILC3 and γδ T cells are hyporesponsive compared to their WT counterparts. In particular, gut NKR-P1B-deficient NK cells and γδT cells secreted low levels of IFNγ cytokine while infected with S.typhimurium. Importantly, the decreased IFNγ secretion by NK and γδT cells was associated with an increased dissemination of the bacterium into the knockout spleens at day 5 post-infection. Likewise, I detected a significant decrease in IL-22 cytokine production by NKR-P1B-deficient ILC3 compared to their WT counterparts at both steady state and following C.rodentium infection.
Next, I address the potential role of Clr-f in the kidney. Renal tubular epithelial cells have been shown to express high levels of Clr-f transcripts. Epithelial cells constitute the major cellular component of kidney tubules and are well known to mediate metabolic waste excretion, reabsorption of essential molecules as well as other physiological functions, such as ions exchange and water retention. To determine the role of Clr-f in renal epithelial cells, I generated a Clr-f-deficient mouse with the help of two of my previous lab colleagues. Importantly, chemical analysis on urine and serum samples from knockout and WT littermates indicated that Clr-f-deficient kidneys display a decreased filtration capacity. In particular, higher creatinine levels were detected in the Clr-f deficient serum. In addition, Clr-f-deficient mice appeared to have a lower fractional excretion of sodium (FENa) in their urine filtrates in comparison to WT excreted urine. Blood pressure measurements on the same mice at 12 and 24 weeks of age revealed a hypotensive phenotype in the Clr-f-deficient mice. Furthermore, pathological assessment of Clr-f-deficient kidneys exhibited moderate and aggravated lesions of the tubular epithelium along with marked glomerular mesangiolysis. Lastly, flow cytometry analysis on isolated lymphocytes from Clr-f-deficient and WT mice demonstrated comparable immune infiltrates between the two mouse genotypes.
Altogether, our data shows that the absence of Clr-f results in the development of glomerular and tubular lesions in an immune-independent manner leading to an abnormal kidney function. Additionally, the disruption of NKR-P1B:Clr-b recognition system results in abnormal innate immune cell number and function in the mouse intestine. These novel findings sheds light on the important role of Clr-f in maintaining healthy kidney morphology and function, as well as the crucial role for NKR-P1B:Clr-b interactions in mediating intestinal homeostasis at steady and infected states.
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Tran, Dinh Minh. "Le test toxinique : une méthode de phénotypage pour l’étude de l’interaction Hevea brasiliensis x Corynespora cassiicola et l'identification des facteurs génétiques de sensibilité." Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT178/document.
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Hevea brasiliensis est la seule source commerciale du caoutchouc naturel. La maladie CLF (Corynespora Leaf Fall) provoquée par le champignon Corynespora cassiicola est une pathologie foliaire de l’hévéa importante en Asie et en Afrique. Les épidémies sont liées au développement de nouvelles variétés clonales très sensibles. Une méthode conductimétrique de phénotypage de la réponse de l’hévéa aux exsudats de C. cassiicola (filtrats de culture ou toxine purifiée) a été développée et caractérisée. Ce test toxinique, sans contact direct avec le champignon lui-même, peut être mis en œuvre sans risque sur les plantations. Après application de gouttes d’exsudats sur des folioles détachées d’un génotype d’hévéa, deux mesures de conductivité C1 et C2 sont réalisées avant et après autoclavage, et le pourcentage de fuite d’électrolyte dû au traitement, %FE = 100*C1/C2, est calculé. L’influence de différents facteurs tels que le stade foliaire et la durée d’incubation, a été précisée. Une corrélation positive a été trouvée entre les réponses au test toxinique et à l’inoculation par des conidies du champignon. La pertinence de la correction de C1 par C2 a été analysée.Deux études du test toxinique ont été réalisées pour une série de clones d’hévéa, d’une part en France avec des plantes en pots cultivées en serre, et d’autre part en Côte d’Ivoire, dans les conditions normalement envisagées pour ce test, avec des folioles provenant de jardins à bois de greffe. La répétabilité entre ces deux études est imparfaite mais néanmoins satisfaisante. Le critère %FE est apparu plus sensible et plus précis que la mesure de la surface de nécrose induite (SN). Une variabilité importante de la sensibilité des clones et de l’agressivité des exsudats a été observée, avec l’existence d’interactions. L’analyse du déterminisme génétique de la réponse au test toxinique a été menée par détection de QTL sur deux populations de la famille biparentale d’hévéa PB260 x RRIM600, analysées sur deux sites en Côte d’Ivoire. Une carte génétique a été construite au préalable avec 308 marqueurs SSR. Le phénotypage des deux populations a révélé un déterminisme polygénique, sans effet monolocus majeur, avec, pour l’ensemble des exsudats fongiques étudiés, 13 QTL répartis sur 10 groupes de liaison et présentant des pourcentages d’explication R2 variant de 10 à 20 %. Sur les deux sites, deux QTL ont été identifiés conjointement pour le filtrat CCP et pour la toxine Cas1 purifiée à partir du filtrat CCP, démontrant l’importance de Cas1 pour la toxicité de ce filtrat. Des corrélations positives entre certains filtrats ont été observées, avec des profils de réponse similaires et des QTL communsLe test toxinique pourrait remplacer avantageusement la méthode d’inoculation conidienne. Cependant, la valeur prédictive du test pour la sensibilité des clones d’hévéa à la maladie CLF en plantation reste à caractériser. Une meilleure connaissance de l’épidémiologie du pathosystème H. brasiliensis x C. cassiicola contribuerait à l’objectif de sélection, et plus largement à la conception de méthodes de lutte ou d’évitementHevea brasiliensis is the only commercial source of natural rubber. The CLF (Corynespora Leaf Fall) disease caused by the fungus Corynespora cassiicola is an important foliar pathology of the rubber tree in Asia and Africa. The disease progression is related with the development of new highly sensitive clonal varieties. A phenotyping method based on the measurement of electrolyte leakage in response to C. cassiicola exudates (culture filtrates or purified toxin) was developed and characterized. This test, without direct contact with the fungus itself, can be implemented without risk for plantations. After application of exudate samples on detached leaflets, conductivity is measured before (C1) and after (C2) autoclaving, and the percentage of electrolyte leakage %FE=100*C1/C2 is calculated. The influence of different factors such as leaf stage or the duration of incubation has been clarified. A positive correlation was found between the responses to the toxin test and to conidial inoculation. The pertinence of C1 correction by C2 was analyzed.Two toxin test studies have been carried out for a set of rubber clones, in France, with potted plants in greenhouse, and also in Ivory Coast, under the conditions normally considered for this test, with leaflets from budwood gardens. Repeatability between these two experiments was not perfect but nevertheless satisfying. The %FE character was found more sensitive and accurate than surface necrosis (SN) measurement. A significant variability in clone susceptibility and treatment virulence was observed, with clone x treatment interactions. The genetic determinism of sensitivity to C. cassiicola exudates was analyzed using the toxin test, by QTL detection on two populations of the biparental rubber family PB260 x RRIM600, in two field trials in Ivory Coast. A genetic map was previously built, using 308 SSR markers. Phenotyping of the two progeny populations revealed a polygenic determinism, without major monolocus effect. Over all the fungal exudates, 13 QTL distributed over 10 different linkage groups were identified, with percentages of explanation R2 varying from 10 to 20 %. On both sites, two QTL have been identified jointly for both the culture filtrate CCP and the toxin Cas1 purified from CCP. Positive correlations have been observed between some of the filtrates, with similar response profiles and common QTL.The toxin test could usefully replace the conidial inoculation method. However, the value of the test for predicting rubber clones susceptibility to the CLF disease in field conditions remains to be better characterized. Better understanding of the epidemiology of the H. brasiliensis x C. cassiicola pathosystem would contribute to the breeding objective, and more broadly to the design of control or avoidance methods
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Boström, Anna. "Cross-Language Information Retrieval : En studie av lingvistiska problem och utvecklade översättningsmetoder för lösningar angående informationsåtervinning över språkliga gränser." Thesis, Umeå University, Sociology, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1017.
Full textAbstract:
Syftet med denna uppsats är att undersöka problem samt lösningar i relation till informationsåtervinning över språkliga gränser. Metoden som har använts i uppsatsen är studier av forskningsmaterial inom lingvistik samt främst den relativt nya forskningsdisciplinen Cross-Language Information Retrieval (CLIR). I uppsatsen hävdas att världens alla olikartade språk i dagsläget måste betraktas som ett angeläget problem för informationsvetenskapen, ty språkliga skillnader utgör ännu ett stort hinder för den internationella informationsåtervinning som tekniska framsteg, uppkomsten av Internet, digitala bibliotek, globalisering, samt stora politiska förändringar i ett flertal länder runtom i världen under de senaste åren tekniskt och teoretiskt sett har möjliggjort. I uppsatsens första del redogörs för några universellt erkända lingvistiska skillnader mellan olika språk – i detta fall främst med exempel från europeiska språk – och vanliga problem som dessa kan bidra till angående översättningar från ett språk till ett annat. I uppsatsen hävdas att dessa skillnader och problem även måste anses som relevanta när det gäller informationsåtervinning över språkliga gränser. Uppsatsen fortskrider med att ta upp ämnet Cross-Language Information Retrieval (CLIR), inom vilken lösningar på flerspråkighet och språkskillnader inom informationsåtervinning försöker utvecklas och förbättras. Målet med CLIR är att en informationssökare så småningom skall kunna söka information på sitt modersmål men ändå hitta relevant information på flera andra språk. Ett ytterligare mål är att den återfunna informationen i sin helhet även skall kunna översättas till ett för sökaren önskat språk. Fyra olika översättningsmetoder som i dagsläget finns utvecklade inom CLIR för att automatiskt kunna översätta sökfrågor, ämnesord, eller, i vissa fall, hela dokument åt en informationssökare med lite eller ingen alls kunskap om det språk som han eller hon söker information på behandlas därefter. De fyra metoderna – identifierade som maskinöversättning, tesaurus- och ordboksöversättning, korpusbaserad översättning, samt ingen översättning – diskuteras även i relation till de lingvistiska problem och skillnader som har tagits upp i uppsatsens första del. Resultatet visar att språk är någonting mycket komplext och att de olika metoderna som hittills finns utvecklade ofta kan lösa något eller några av de uppmärksammade lingvistiska översättningssvårigheterna. Dock finns det inte någon utvecklad metod som i dagsläget kan lösa samtliga problem. Uppsatsen uppmärksammar emellertid även att CLIR-forskarna i hög grad är medvetna om de nuvarande metodernas uppenbara begränsningar och att man prövar att lösa detta genom att försöka kombinera flera olika översättningsmetoder i ett CLIR-system. Avslutningsvis redogörs även för CLIR-forskarnas förväntningar och förhoppningar inför framtiden.
This essay deals with information retrieval across languages by examining different types of literature in the research areas of linguistics and multilingual information retrieval. The essay argues that the many different languages that co-exist around the globe must be recognised as an essential obstacle for information science. The language barrier today remains a major impediment for the expansion of international information retrieval otherwise made technically and theoretically possible over the last few years by new technical developments, the Internet, digital libraries, globalisation, and moreover many political changes in several countries around the world. The first part of the essay explores linguistic differences and difficulties related to general translations from one language to another, using examples from mainly European languages. It is suggested that these problems and differences also must be acknowledged and regarded as highly important when it comes to information retrieval across languages. The essay continues by reporting on Cross-Language Information Retrieval (CLIR), a relatively new research area where methods for multilingual information retrieval are studied and developed. The object of CLIR is that people in the future shall be able to search for information in their native tongue, but still find relevant information in more than one language. Another goal for the future is the possibility to translate complete documents into a person’s language of preference. The essay reports on four different CLIR-methods currently established for automatically translating queries, subject headings, or, in some cases, complete documents, and thus aid people with little or no knowledge of the language in which he or she is looking for information. The four methods – identified as machine translation, translations using a multilingual thesaurus or a manually produced machine readable dictionary, corpus-based translation, and no translation – are discussed in relation to the linguistic translation difficulties mentioned in the paper’s initial part. The conclusion drawn is that language is exceedingly complex and that while the different CLIR-methods currently developed often can solve one or two of the acknowledged linguistic difficulties, none is able to overcome all. The essay also show, however, that CLIR-scientists are highly aware of the limitations of the different translation methods and that many are trying to get to terms with this by incorporating several sources of translation in one single CLIR-system. The essay finally concludes by looking at CLIR-scientists’ expectations and hopes for the future.
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Amarasinghe, Ishari. "The Orchestration of computer-supported collaboration scripts with learning analytics." Doctoral thesis, Universitat Pompeu Fabra, 2020. http://hdl.handle.net/10803/670420.
Full textAbstract:
Computer-supported collaborative learning (CSCL) creates avenues for productive collaboration between students. In CSCL, collaborative learning flow patterns (CLFPs) provide pedagogical rationale and constraints for structuring the collaboration process. While structured collaboration facilitates the design of favourable learning conditions, orchestration of collaboration becomes an important factor, as learner participation and real-world constraints can create deviations in real time. On the one hand, limited research has examined the orchestration challenges related to collaborative learning situations scripted according to CLFPs in authentic educational contexts to resolve collaboration at different scales. On the other hand, learning analytics (LA) can be used to provide proper technological tooling, infrastructure and support to orchestrate collaboration. To this end, this dissertation addresses the following research question: How can LA support orchestration mechanisms for scripted CSCL? To address this question, this dissertation first focuses on studying the orchestration challenges associated with scripted CSCL situations on small scales (in the classroom learning context) and large scales (in the distance learning context, specifically in massive open online courses [MOOCs]). In the classroom learning context, lack of teacher access to activity regulation mechanisms constituted a key challenge. In MOOCs, sustained student participation in multiple phases of the script was a primary challenge. The dissertation also focuses on studying the design of LA interventions that might address the orchestration challenges under examination. The proposed LA interventions range from human-in-control to machine-in-control in nature given the feasibility and regulation needs of the learning contexts under investigation. Following a design-based research (DBR) methodology, evaluation studies were conducted in naturalistic classrooms and in MOOCs to evaluate the effects of the proposed LA interventions and to understand the conditions for their successful implementation. The results of the evaluation studies conducted in the classroom context shed light on how teachers interpret LA data and how they action the resulting knowledge in authentic collaborative learning situations. In the distance learning context, the proposed interventions were critical in sustaining continuous flows of collaboration. The practical benefits and limitations of deploying LA solutions in real-world settings, as well as future research directions, are outlined.El aprendizaje colaborativo asistido por ordenador (CSCL) ofrece oportunidades para la colaboración productiva entre estudiantes. En CSCL, los patrones de flujo de aprendizaje colaborativo (CLFP) proporcionan un fundamento pedagógico y restricciones para estructurar el proceso de colaboración. Si bien la colaboración estructurada facilita el diseño de condiciones de aprendizaje favorables, la orquestación de dicha colaboración estructurada se convierte en un factor importante, ya que la participación del alumno y los condicionantes del mundo real pueden crear desviaciones en el momento de su realización. Por un lado, existe una investigación limitada sobre los desafíos de la orquestación de aprendizaje colaborativo guiado según los CLFP en contextos educativos auténticos a diferentes escalas. Por otro lado, la analítica del aprendizaje (LA) se puede utilizar para proporcionar las herramientas tecnológicas, la infraestructura y el apoyo adecuados para orquestar la colaboración. Con este fin, esta tesis doctoral plantea la siguiente pregunta de investigación: ¿Cómo puede LA apoyar los mecanismos de orquestación de guiones de CSCL? Para abordar esta pregunta, la tesis doctoral se centra, primero, en estudiar los desafíos de la orquestación en situaciones CSCL guiadas a pequeña escala (en el contexto del aula) y a gran escala (en el contexto de aprendizaje a distancia, específicamente en cursos masivos abiertos en línea [MOOC]). En el contexto del aula, un reto imporante es la falta de acceso de los docentes a los mecanismos de regulación de la actividad. En los MOOC, el reto principal es sostener la participación de los estudiantes a lo largo de las diversas fases del guión. La tesis doctoral también se centra en estudiar el diseño de intervenciones de LA que podrían abordar los retos de orquestación detectados. Dadas las necesidades de viabilidad y regulación de los contextos de aprendizaje investigados, las intervenciones de LA propuestas van desde acciones automáticas donde la “máquina está en control” a intervenciones que implican “control por humanos”. Siguiendo una metodología de investigación basada en el diseño (DBR), se han realizado estudios en aulas y en MOOCs para evaluar los efectos de las intervenciones de LA propuestas y comprender las condiciones para su buena implementación. Los resultados de la evaluación realizada en el contexto del aula arrojan luz sobre cómo los profesores interpretan los datos de LA y cómo actúan en consecuencia en situaciones auténticas de aprendizaje colaborativo. En el contexto de la educación a distancia, las intervenciones propuestas fueron fundamentales para mantener flujos continuos de colaboración. La tesis docotral describe los beneficios prácticos y las limitaciones a la hora de implementar soluciones de LA en entornos reales, así como las direcciones de investigación futuras.
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Dunstan, Neal Edward. "Steps to the identification of the residue of the cultural heritage landscape of the University of Pretoria's Hatfield campus 1910-1960." Diss., University of Pretoria, 2016. http://hdl.handle.net/2263/61291.
Full textAbstract:
As the Campus Landscape Architect for the University of Pretoria, it has been an on-going challenge to gain an understanding and reliable data on the history of the landscape of the University of Pretoria's Hatfield campus. With the pace of development taking place on the campus, in order to meet the University's 2025 Strategic Vision, it became very clear that potential significant cultural landscapes on the Hatfield campus could be lost without ever knowing it. This is especially even more so when related to the South African Heritage Resources Act 25 of 1999 (SAHRA). The Getty Foundation's Campus Heritage Initiative's first grant for a conference in 2000 shared consensus that historic landscape preservation had a very low profile in much of American campus planning
The hypothesis states that the University of Pretoria's Hatfield Campus has an undiscovered cultural landscape history that not only could have value to the development of the University, but also to that of the surrounding precincts of the City. The thesis's aim is to record any sourced data pertaining to the cultural landscape of the University of Pretoria's Hatfield campus in order to contribute to the institutional repository, and to ascertain what, if any, cultural landscape values exist. A complex descriptive and historiographical interpretative research strategy was followed. A literature, policy and model study was conducted resulting in the main research tool being the U.S. Department of the Interior National Park Service's Cultural Landscape Report (CLR). The limitation to the thesis was Part 1: Site History, Existing Conditions, Analysis and Evaluation of the CLR to the University of Pretoria's Hatfield Campus for the period 1910 to 1960.
The study highlighted that the Hatfield Campus does contain tangible cultural landscape elements but very little is known or present of the intangible elements. The current political climate of the University places emphasis on equalising the cultural diversity on campuses, perhaps to the detriment of the existing cultural landscape, mainly by the naming and/or renaming of its buildings. A recommendation is that a Management and Preservation Plan encompassing both the architectural and landscape aspects be compiled to inform the future planning of the campus.Dissertation (MLA)--University of Pretoria, 2016.
Architecture
MLA
Unrestricted
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Deon, Marine. "Importance de la cassiicoline en tant qu'effecteur de la Corynespora Leaf Fall (CLF) chez l'hévéa : Développement d'outils pour le contrôle de la maladie." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2012. http://tel.archives-ouvertes.fr/tel-00741952.
Full textAbstract:
L'hévéa (Hevea brasiliensis) est actuellement la seule source commerciale de caoutchouc naturel. Parmi les maladies affectant l'hévéa, la CLF (" Corynespora Leaf Fall ") causée par le champignon Corynespora cassiicola, est devenue en une cinquantaine d'années un fléau pour l'ensemble des pays hévéicoles d'Asie et d'Afrique. Actuellement, la gestion du problème consiste à arracher les clones les plus sensibles et à traiter les arbres avec des fongicides en cas d'épidémie. Cependant, le nombre de clones touchés par la maladie ne cessant d'augmenter, il devient urgent de sélectionner de nouveaux clones à la fois tolérants et aptes à la production. Nos travaux ont permis de caractériser le gène codant la cassiicoline, toxine protéique glycosylée secrétée par C. cassiicola, et d'analyser sa diversité. Une étude comparative portant sur trois isolats de C. cassiicola d'agressivité contrastée a montré la présence du gène Cas1 chez les isolats de forte et moyenne agressivité, alors qu'il n'est pas détecté chez l'isolat de faible agressivité. Les niveaux d'agressivité des isolats sont corrélés aux niveaux de transcrits du gène de cassiicoline. Le rôle de la cassiicoline serait prépondérant dans les phases précoces de l'infection. L'analyse de diversité du gène de cassiicoline à partir d'une collection d'isolats provenant de différents hôtes et d'origines géographiques variées, a révélé l'existence d'au moins six isoformes protéiques (Cas1 à Cas6). La structuration génétique globale des isolats basée sur des marqueurs neutres est similaire à la structuration basée sur le gène de cassiicoline. Les isolats prélevés sur hévéa se regroupent en clades spécialisés, dont un correspondant aux isolats porteurs du gène Cas1, identifiés comme étant les plus agressifs sur hévéa. Cependant, 58 % des isolats testés semblent dépourvus de gène de cassiicoline, bien que certains génèrent des symptômes modérés sur hévéa, ce qui suggère l'existence d'autres effecteurs. Des formes endophytiques de C. cassiicola ont été isolées à partir de feuilles asymptomatiques provenant du Brésil, zone encore indemne de CLF. Les gènes de cassiicoline portés par ces souches (isoformes Cas3 et 4) ne semblent pas exprimés lors de l'interaction avec l'hévéa. Nous avons montré par ailleurs que les champignons endophytes de l'hévéa appartenant aux genres Trichoderma et Xylaria présentent une forte activité mycoparasitaire sur C. cassiicola, in vitro. Ces travaux ouvrent de nouvelles perspectives pour le contrôle de la maladie (diagnostic précoce, sélection de clones tolérants, lutte biologique).
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Loza, Christian. "Cross Language Information Retrieval for Languages with Scarce Resources." Thesis, University of North Texas, 2009. https://digital.library.unt.edu/ark:/67531/metadc12157/.
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Our generation has experienced one of the most dramatic changes in how society communicates. Today, we have online information on almost any imaginable topic. However, most of this information is available in only a few dozen languages. In this thesis, I explore the use of parallel texts to enable cross-language information retrieval (CLIR) for languages with scarce resources. To build the parallel text I use the Bible. I evaluate different variables and their impact on the resulting CLIR system, specifically: (1) the CLIR results when using different amounts of parallel text; (2) the role of paraphrasing on the quality of the CLIR output; (3) the impact on accuracy when translating the query versus translating the collection of documents; and finally (4) how the results are affected by the use of different dialects. The results show that all these variables have a direct impact on the quality of the CLIR system.
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Osorio, Osorio Bertha. "Determinación de la cinética de degradación fotolítica y tiempo de vida media de la ranitidina en medio acuoso por cromatografía de líquidos de alta resolución (CLAR)." Tesis de Licenciatura, Universidad Autónoma del Estado de México, 2018. http://hdl.handle.net/20.500.11799/95041.
Full textAbstract:
Se presenta una Investigación del comportamiento químico de la ranitidina bajo radiación ultravioleta en medio acuoso.Muchos compuestos farmacológicamente activos son arrojados al agua durante los procesos de fabricación, así como también por una mala disposición de los medicamentos caducos y de efluentes hospitalarios. Los compuestos farmacéuticos no pueden ser eliminados por completo de las aguas residuales, por lo tanto, pueden ser encontrados en una amplia gama de muestras ambientales incluidos los efluentes de las plantas de tratamiento de aguas residuales, superficiales, subterráneas e incluso en el agua potable, en todo el mundo. La ranitidina es un fármaco antiulceroso, antagonista de los receptores H2 de histamina, que se utiliza para bloquear la acción de esta amina biogénica sobre las células parietales del estómago, disminuyendo la producción del ácido. Es uno de los fármacos más prescriptos en todo el mundo; tan sólo en 2003 en España se vendieron 5648 miles de unidades; está presente en el cuadro básico de medicamentos del sector salud en México, por lo que se supone que su presencia en agua residual sea alta. De aquí surge el interés de determinar la vida media en agua y el tiempo en el que inicia la degradación. En la actualidad los residuos de los fármacos que ya son considerados medicamentos caducos o que provienen del metabolismo posterior a la administración del mismo, en su mayoría terminan en aguas residuales de carácter municipal, en lugar de tener un proceso llamado disposición final o de una correcta eliminación que sea eficiente; por tal motivo, se han encontrado trazas de fármacos en aguas potables y mares, las trazas de algunos fármacos y los productos de degradación de los mismos, pueden tener características tóxicas para los humanos o para la flora y fauna del ecosistema, afectan su equilibrio y provocan daños irreversibles. Es por ello que se desea investigar acerca de la eliminación por radiación ultravioleta.
Proyecto CONACYT 215996
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Nyman, Marie, and Maria Patja. "Cross-language information retrieval : sökfrågestruktur & sökfrågeexpansion." Thesis, Högskolan i Borås, Institutionen Biblioteks- och informationsvetenskap / Bibliotekshögskolan, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-18892.
Full textAbstract:
This Master’s thesis examines different retrieval strategies used in cross-language information retrieval (CLIR). The aim was to investigate if there were any differences between baseline queries and translated queries in retrieval effectiveness; how the retrieval effectiveness was affected by query structuring and if the results differed between different languages. The languages used in this study were Swedish, English and Finnish. 30 topics from the TrecUta collection were translated into Swedish and Finnish. Baseline queries in Swedish and Finnish were made and translated into English using a dictionary and thereby simulating automatic translation. The queries were expanded by adding all the translations from the main entries to the queries. Two kinds of queries – structured and unstructured – were designed. The queries were fed into the InQuery IR system which presented a list of retrieved documents where the relevant ones were marked. The performance of the queries was analysed by Query Performance Analyser (QPA). Average precision at seen relevant documents at DCV 10, average precision at DCV 10 and precision and recall at DCV 200 were used to measure the retrieval effectiveness. Despite the morphological differences between Swedish and Finnish, none or very small differences in retrieval performance were found, except when average precision at DCV 10 was used. The baseline queries performed the best results and the structured queries performed better in both Swedish and Finnish than the unstructured queries. The results are consistent with previous research.Uppsatsnivå: D
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Rahabi, Mouna. "Les macrophages dans l'inflammation colique, approches expérimentale et translationnelle : impact des récepteurs Dectine-1 et mannose et des peptides Naticol(r)Gut." Thesis, Toulouse 3, 2020. http://www.theses.fr/2020TOU30104.
Full textAbstract:
La maladie de Crohn (MC) et la rectocolite hémorragique (RCH) sont les deux formes principales des maladies inflammatoires chroniques de l'intestin (MICI) et sont le résultat de réactions inflammatoires excessives au niveau du système digestif. Bien qu'elles partagent certaines caractéristiques, ces deux entités se distinguent par des différences concernant la prédisposition génétique, les facteurs de risque, et les caractéristiques cliniques, endoscopiques et histologiques. Dans un premier temps, nous nous sommes intéressés au rôle des récepteurs lectines de type C dans l'inflammation colique. Nous montrons que dans un contexte de colite, l'absence de Dectine-1 prévient l'inflammation intestinale, tandis que l'absence du récepteur mannose (RM), l'exacerbe. Ceci a été confirmé dans un modèle expérimental d'exposition au DSS sur souris déficientes pour le RM chez qui nous avons relevé une augmentation marquée de l'expression de Dectine-1. Dectine-1 participe au recrutement des monocytes sanguins, précurseurs des macrophages, sur le site inflammatoire de la muqueuse colique et favorise la production d'IL-1ß de façon leucotriène B4- dépendante. Nous associons donc l'inflammation colique à une activation de l'axe Dectine-1/CCL2/LTA4H et à une régulation négative du RM sur les macrophages de patients atteints de MICI. Par ailleurs, la deuxième partie de notre travail montre que les peptides de collagène de poisson, dont les propriétés anti- inflammatoires ont été décrites dans d'autres contextes pathologiques tels que l'arthrite ou les dérégulations métaboliques, ont un effet bénéfique dans un contexte d'inflammation colique. Le Naticol(r)Gut, nom commercial des peptides de collagène de poisson que nous avons étudiés, régule l'inflammation par effet direct sur la polarisation des macrophages coliques vers un phénotype anti-inflammatoire et anti-oxydant. Par conséquent, nous avons montré que l'administration de Naticol(r)Gut module l'équilibre Th1/Th2 des cellules T CD4 en faveur d'une réponse Th2 et limite l'activation des cellules T CD8 cytotoxiques. L'atténuation du statut inflammatoire de l'intestin généré par l'administration de Naticol(r)Gut entraîne une eubiose intestinale subséquente caractérisée par une limitation du développement des espèces pathobiontes au profit des espèces probiotiques. De plus, nous observons des contributions similaires du Naticol(r)Gut dans la restauration du phénotype anti-inflammatoire, anti-oxydant et immuno-tolérant des monocytes humains de sujets atteints de MICI. Ces deux études appuient le rôle crucial que joue la polarisation des macrophages dans la physiopathologie de l'inflammation colique. Enfin, ce dernier travail appuierait l'effet protecteur du RM, récepteur au collagène, dans la coliteCrohn's disease (CD) and ulcerative colitis (UC) are the two main forms of chronic inflammatory bowel disease (IBD) and are the result of excessive inflammatory reactions in the digestive system. Although they share some characteristics, they are distinguished by differences in genetic predisposition, risk factors, and clinical, endoscopic and histological features. First, we have focused on the role of C-type lectin receptors in colonic inflammation. We show that in a colitis context the absence of Dectin-1 prevents intestinal inflammation, while the absence of the mannose receptor (MR) exacerbates it. This was confirmed in an experimental model of DSS exposure in MR-deficient mice in which we found a marked increase in the expression of Dectin-1. Dectin-1 is involved in the recruitment of blood monocytes, precursors of macrophages, to the inflammatory site of the colonic mucosa and promotes the production of IL-1ß in a leukotriene-B4-dependent manner. We therefore associate colonic inflammation with the activation of the Dectin1/CCL2/LTA4H axis and with a negative regulation of MR in macrophages from IBD patients. In addition, the second part of our work shows that fish collagen peptides, whose anti-inflammatory properties have been described in other pathological contexts such as arthritis or metabolic deregulation, have a beneficial effect in a context of colonic inflammation. Naticol(r)Gut, the trade name of the fish collagen peptides we studied, regulates inflammation by direct effect on the polarization of colonic macrophages towards an anti-inflammatory and antioxidant phenotype mediated by the recognition by the MR thereby supporting its protective effect. Therefore, we have shown that Naticol(r)Gut administration modulates the Th1/Th2 balance of CD4 T cells in favor of a Th2 response and limits the activation of cytotoxic CD8 T cells. The attenuation of the intestinal inflammatory status generated by the administration of Naticol(r)Gut subsequently leads to intestinal eubiosis characterized by a limitation of the development of pathobiontic species in favor of probiotic species. In addition, we observe similar contributions of Naticol(r) in restoring the anti-inflammatory, antioxidant and immunotolerant phenotype of human monocytes from subjects with IBD. These two studies support the crucial role of macrophage polarization through the C-type lectin receptors in the pathophysiology of colonic inflammation. Finally, the latter work supports the protective effect of the MR collagen receptor in colitis
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Huertas, López David. "Estudi de la distribució dels compostos organoclorats en els organismes fluvials sota la influència dels efluents d’una planta clor-àlcali (riu Ebre, entre Mequinensa i el Delta)." Doctoral thesis, Universitat de Barcelona, 2015. http://hdl.handle.net/10803/336970.
Full textAbstract:
Els compostos orgànics persistents (COPs) són un conjunt de contaminants que comparteixen una sèrie de característiques comuns. Com el seu nom indica, poden romandre en el medi ambient durant llargs períodes de temps, són molt estables i no es degraden amb facilitat. D'altra banda són tòxics i a causa de les seves propietats fisico-químiques es distribueixen per tot el planeta transportant-se a llocs remots allunyats dels focus emissors. A més, en ser lipofílics, tenen una gran capacitat de bioacumulació en els organismes i per tant es biomagnifiquen al llarg de les xarxes tròfiques.
La producció de compostos organoclorats durant el darrer segle per part de l'empresa cloro¬àlcali situada a Flix (al sud oest de Catalunya), ha donat lloc a l'acumulació de fangs contaminats a l'embassament d'aquesta població. Tradicionalment, en relació a les concentracions de contaminants orgànics, els organismes han estat tractats de forma parcial en tot aquest tram final del riu Ebre. Es per aquesta raó que en aquesta tesi s'ha realitzat un estudi més complet de la seva distribució i impacte sobre tots els nivells de les xarxes tròfiques fluvials tot començant pels nivells tròfics inferiors i incloent els principals depredadors. Això ha representat l'anàlisi de diversos compostos organoclorats en diferents matrius biòtiques i abiòtiques: els clorobenzens (PeCB i HCB), els policlorobifenils (PCBs), els hexaclorociclohexans (HCHs), el diclorodifeniltricloroetà (DDT) i els seus metabòlits, així com també els policloroestirens (PCEs). Per complementar la recerca s'ha volgut estudiar la presència d'aquests compostos a llocs allunyats de les principals fonts d'emissió. Per fer això, s'han analitzat mostres al llarg de tot el tram baix del riu Ebre, per comprovar si hi havia diferències de concentracions respecte a l'embassament de Flix, diferències en els patrons de distribució de COPs, o en els fenòmens de biomagnificació d'aquests compostos.
Així mateix aquesta tesi estudia l'impacte que ha tingut la fàbrica clor-àlcali situada a l'embassament de Flix sobre les xarxes tròfiques del darrer tram del riu Ebre, i com aquest focus de contaminació puntual, ha afectat els llocs situats a distàncies llargues de les emissions i abocaments. Primer s'estudien les concentracions de COPs i les relacions entre els nivells tròfics inferiors de l'embassament de Flix. En segon lloc s'avaluen els nivells de contaminants que tenen els peixos tant a l'embassament com aigües avall. En tercer lloc es determina l'efecte que tenen els compostos organoclorats en els estadis superiors de les xarxes tròfiques fluvials: els ocells. Per finalitzar, es condensa tota la informació relacionada amb la biomagnificació dels contaminants al llarg de la xarxa tròfica dins de l'embassament de Flix.Persistent organic pollutants (POPs) are a well-known group of contaminants that have in common some characteristics. As its name indicates, they can remain in the environment for long periods of time, they are stable and do not degrade easily. Furthermore, they are toxic and because of their physical and chemical properties they can be distributed throughout the planet reaching remote places far away from pollution sources. In addition, they are lipophilic and with great capacity to bioaccumulate inside the organisms so they are biomagnified along food webs. The production of organochlorine compounds during the last century by the chlor-alkali plant located at Flix (South West Catalonia) has generated an accumulation of polluted muds inside the water reservoir from this locality. Concerning the concentrations of organic pollutants, so far the organisms living in the last stretch of the Ebro River have only been considered partially. This thesis includes a complete study of the distribution and accumulation of these compounds in fluvial food webs starting from the lower trophic levels and including main predators. Different organochlorine compounds have been analyzed in a wide range of biotic and non-biotic matrices: chlorobenzenes (PeCB and HCB), polychlorobiphenyls (PCBs), hexachlorocyclohexanes (HCHs), dichlorodiphenyltrichloroethane (DDT) and its metabolites, as well as the polychlorostyrenes (PCSs). To complement this research, the presence of these compounds has been assessed in sites located far away from main pollution sources. To achieve this, samples from the last stretch of the Ebro River have been analysed in order to assess if there were differences in concentrations in comparison to samples from the Flix water reservoir, differences in distribution patterns of POPs, or differences at the biomagnification processes of these compounds. Firstly it studies concentrations of POPs and the relationships between lower trophic levels from the Flix water reservoir. Secondly it evaluates levels of contaminants from fish inside the Flix water reservoir and downstream. Third, it determines the effect that POPs have at higher trophic levels from fluvial food webs: birds. Finally, it integrates all the information related to the biomagnification of pollutants along the food web within the Flix water reservoir.
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Förderer, Alexander [Verfasser], Coupland [Gutachter] George, and Höcker [Gutachter] Ute. "Unequal genetic redundancy between the PcG proteins CLF and SWN has created distinct biochemical properties / Alexander Förderer ; Gutachter: Coupland George, Höcker Ute." Köln : Universitäts- und Stadtbibliothek Köln, 2018. http://d-nb.info/1196788529/34.
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Harsh, Bethanie. "Redescribing Agency through Sport and Ritual: Considering an Alternative Approach." Digital Archive @ GSU, 2011. http://digitalarchive.gsu.edu/rs_theses/35.
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This project exposes the problems with the dominant conception of agency in secular liberal discourse. The main critique is that the dominant conception of agency tends to attribute value to certain aspects of action that are not necessarily the most telling or valuable in terms of what constitutes agency. I use Saba Mahmood’s Politics of Piety to aid in this critique. Her project uses the Muslim rituals performed by women of the mosque movement in Egypt to demonstrate the need for a more nuanced conception of agency in academics. I use CLR James’ Beyond a Boundary to support the approach offered by Mahmood and demonstrate the applicability of such an approach outside of typical considerations of “ritual”. In this case, the approach is applied to cricket.
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Anhuaman, Laura Andrea Leon. "Fatores comportamentais, hormonais e neuroanatômicos associados à vulnerabilidade ao estresse em ratos Carioca High Conditioned-Freezing (CHF) e Carioca Low Conditioned-Freezing (CLF)." Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/59/59134/tde-03042014-174324/.
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A ansiedade e a depressão são as condições psicopatológicas mais comuns na atualidade. As pesquisas científicas em neurociência, psicologia, psiquiatria e medicina geral procuram encontrar diferentes formas para o tratamento e prevenção. No entanto, a maioria das pesquisas não leva em conta as diferenças individuais ou história do individuo. Quase toda a investigação farmacológica é feita em populações heterogêneas de animais, conduzindo assim à \"média\" dos dados. Recentemente, no Laboratório de Neurociência Comportamental na Pontifícia Universidade Católica do Rio de Janeiro (PUC-RJ), duas novas linhagens de ratos Wistar foram selecionadas fenotipicamente da resposta emocional de congelamento em um teste de medo condicionado . Uma das linhagens, denominada Carioca High ConditionedFreezing (CHF), apresenta uma resposta significativamente aumentada de congelamento no teste, enquanto que a outra (Carioca Low Conditioned-Freezing, CLF) mostra uma resposta de congelamento baixa. Em todos os experimentos utilizamos a linhagem controle (Random, RND) Wistar resultado de cruzamento aleatório entre ratos Wistar. Aqui apresentamos dados de diversos experimentos que avaliaram as diferenças em condições basais e vulnerabilidade ao estresse entre as duas linhagens e a linhagem RND. A concentração plasmática de corticosterona dos ratos foi comparada entre as duas linhagens e o grupo RND, primeiramente no nível basal e posteriormente após a exposição ao mesmo teste, onde foram expostos ao medo condicionado, como estímulo aversivo. Também foi avaliada a proliferação celular e sobrevivência. A imuno-histoquímica para c-fos foi conduzida com o objetivo de se determinar as diferenças de atividade neural entre as duas linhagens e o grupo RND. Um teste farmacológico com ketanserina, antagonista 5-HT2A, foi realizado e os animais foram avaliados quanto à ansiedade e locomoção, no labirinto em cruz elevado. Todos os nossos resultados mostraram diferenças estatisticamente significativas entre as linhagens selecionadas. Estes resultados sugerem que as diferentes condições basais podem ter impacto sobre a reação de comportamento exibido por cada animal. Assim, o uso de grupos selecionados é melhor para se modelar transtornos de ansiedade e procurar quais são caraterísticas que protegem aos animais que não apresentam os sintomas modelados. A partir dos nossos resultados foi evidente que os perfis comportamentais e neuroquímicos dos três grupos CHF, CLF e RND foram qualitativamente e quantitativamente diferentes. Na linha de base após ser fenotipados foi observado que existem diferenças na proliferação celular. Após a reexposição ao contexto observaram-se diferenças na concentração de corticosterona e na ativação neuronal. O estresse crônico levou a respostas diferenciais no número de neurônios imaturos, e o teste farmacológico levou a respostas diferencias tanto a nível local como sistêmico. Os dados obtidos podem ajudar a um melhor entendimento às bases neurobiológicas de aspectos associados às psicopatologias como ansiedade e depressão que estão relacionadas com a vulnerabilidade ao estresse.Anxiety and depression are the most common psychopathological conditions today. Scientific research in neuroscience, psychology, psychiatry and general medicine seeks to find different ways for treatment and prevention. However, most research does not take into account individual differences and history. Almost all pharmacological research is done in heterogeneous populations of animals, thereby leading to the \"average\" data. Recently, in the Laboratory of Behavioral Neuroscience at the Pontifical Catholic University of Rio de Janeiro (PUC - RJ), two new strains of rats were selected phenotypically by their emotional response (freezing) in a test of cond itioned fear. One of the lines, so called \"Carioca High Conditioned - Freezing\" (CHF) has an increased freezing in the test , whereas the other (\"Carioca Low -Conditioned Freezing \" CLF) shows low freezing response . In all experiments we used the Wistar control strain (RND) derived from random bred between Wistar rats. Here we present data from several experiments evaluating the differences in basal conditions and vulnerability to stress between the two strains and RND strain. The plasma corticosterone of rats was compared between the two lines and the RND group, first at baseline and then after exposure to the same test where the y were exposed to conditioned fear as aversive stimulus. We also analyzed the cell proliferation and survival in the hippocampus after chronic stress. Immunohistochemistry for c -fos was conducted in order to determine the differences in neural activity between the two strains and the RND group. A pharmacological test with ketanserin, 5 -HT2A antagonist, was performed and the animals were assessed for anxiety and locomotion in the elevated plus maze. All our results showed statistically significant differences between the selected strains. These results suggest that different baseline conditions may have an impact on the behavior exhibited by each animal. Thus the use of selected groups is better approach in order to model anxiety disorders and to determine which features prevent animal from presenting symptoms. It is evident that the neurochemical and behavioral profiles of the three groups CHF, CLF and RND were different qualitatively and quantitatively. At baseline after been phenotyped it has been observed that there are differences in cell proliferation and corticosterone concentration. After re-exposure to the context differences were observed in the concentration of corticosterone and neuronal activation. Chronic stress has led to differential responses in the number of immature neurons. And the pharmacological test led to differential responses at both local and systemic. The data obtained are useful for a better understanding of the neurobiological aspects associated with psychopathologies such as anxiety and depression that are associated with vulnerability to stress.
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Ribeiro, Sébastien. "Rôle de la cassiicoline dans l'interaction compatible Hevea brasiliensis / Corynespora cassiicola : vers la sélection assistée par effecteur : Biologie végétale." Thesis, Université Clermont Auvergne (2017-2020), 2019. http://www.theses.fr/2019CLFAC010/document.
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L'hévéa (Hevea brasiliensis) est la seule source de caoutchouc naturel commercialisé à travers le monde. En Afrique et en Asie, la maladie 'Corynespora Leaf Fall' (CLF), causée par le champignon nécrotrophe Corynespora cassiicola, affecte les plantations hévéicoles en provoquant des défoliations massives sur les clones les plus sensibles. L’évaluation précoce de la sensibilité des clones dans les programmes de sélection est un enjeu majeur pour écarter les individus les plus sensibles des programmes de développement et ainsi réduire la pression de la maladie. Une des méthodes d’évaluation envisagée consiste à tester indirectement la sensibilité des clones aux effecteurs fongiques responsables de la virulence (test toxinique). Parmi tous les effecteurs potentiels du champignon identifiés in silico, seule la cassiicoline Cas1 a été purifiée et caractérisée à ce jour. Il s’agit d’une petite glycoprotéine sécrétée qui jouerait un rôle dans les phases précoces de l’infection en induisant la nécrose des tissus. Les souches porteuses du gène Cas1 sont parmi les plus agressives sur les clones d'hévéa testés. Néanmoins, certaines souches de C. cassiicola ne produisant pas de cassiicoline présentent tout de même une agressivité modérée, suggérant l'implication d'autres effecteurs dans l'établissement de la maladie CLF. Les objectifs de cette thèse sont (i) de déterminer si la sensibilité à la cassiicoline Cas1 est un critère de sélection pertinent pour identifier les clones d’hévéa les plus sensibles à la maladie CLF, et (ii) d’identifier chez l’hévéa des facteurs de sensibilité à la cassiicoline Cas1. Nous avons d'abord analysé l’inoculum naturel et montré que les souches porteuses du gène Cas1 représentent un quart de la population de C. cassiicola dans les plantations d’hévéa d’Afrique de l’Ouest, le reste étant majoritairement constitué de souches dépourvues du gène codant la cassiicoline (Type A/Cas0). Nous avons ensuite créé un mutant de délétion du gène Cas1 pour la souche de référence CCP et comparé sa virulence à celle de la souche sauvage. Nous avons ainsi pu montrer que la cassiicoline Cas1 est bien un effecteur de nécrotrophie déterminant pour la virulence de C. cassiicola chez l’hévéa puisque la souche délétée perd toute virulence sur les clones testés. Enfin, nous avons recherché chez l'hévéa des facteurs de sensibilité à la cassiicoline Cas1 à travers deux approches. La technique de "double hybride en levures" nous a permis d'identifier une trentaine de protéines candidates qui pourraient interagir physiquement avec la toxine. Une approche transcriptomique, nous a permis d’identifier les gènes d’hévéa dont l’expression est modifiée suite à l’application de la cassiicoline purifiée, en comparant un clone sensible (PB260) et un clone tolérant (RRIM600). En conclusion, ces travaux ont permis de mieux comprendre les mécanismes impliqués dans l'interaction compatible entre C. cassiicola et l'hévéa et ouvrent la voie de la sélection assistée par effecteurThe rubber tree (Hevea brasiliensis) is the primary commercial source of natural rubber worldwide. In Asia and Africa, H. brasiliensis is affected by the Corynespora leaf fall (CLF) disease, caused by the broad-spectrum necrotrophic fungus Corynespora cassiicola. During severe attacks, massive fall of young leaves can occur in susceptible cultivars. Early evaluation of the susceptibility of rubber clones in breeding programs is required to avoid developing highly susceptible clones that would amplify the disease. An indirect phenotyping procedure envisaged consists in testing the sensitivity to the fungal toxins (or effectors) rather than the susceptibility to the fungus itself (toxin test). Among all putative effectors identified in silico, only cassiicolin Cas1 has been purified and characterized to date. This small secreted glycoprotein was for long suspected to play a role in the early phase of infection by inducing tissue necrosis. Strains carrying the Cas1 gene are the most aggressive on tested rubber clones. However, strains without cassiicolin gene (called Cas0) still show moderate aggressiveness, suggesting the existence of effectors other than cassiicolin. The objectives of this study are (i) to determine if susceptibility to cassiicolin Cas1 is a relevant selection criterion to eliminate the rubber clones most susceptible to CLF disease, and (ii) identify molecular factors involved in the sensitivity to Cas1, in rubber tree. We have thus analyzed the typology of a large set of C. cassiicola isolates collected from various rubber plantations in West Africa. Our results show that isolates carrying the cassiicolin isoform Cas1 are widely represented, but that the most represented type (A/Cas0) are isolates without cassiicolin gene. Here we show that deletion of the cassiicolin gene in the isolate CCP resulted in a total loss of virulence. This clearly demonstrated that cassiicolin is indeed a necrotrophic effector required for the virulence of isolate CCP in rubber tree. Finally, we have investigated susceptibility factors to cassiicolin Cas1 on rubber tree with two different approaches. We identified about thirty candidate proteins that could physically interact with the toxin, through the two-hybrid assay. A transcriptomic approach allowed us to identify the rubber genes differentially expressed in response to the purified cassiicolin, comparing a susceptible clone (PB260) and a tolerant clone (RRIM600). In conclusion, we think that the necrotrophic effector Cas1 can be an interesting tool for effector-based selection of tolerant clones for African plantations; however, efforts should also be placed on A/Cas0 isolates, in order to identify potential necrotrophic effector(s) responsible for their virulence. This would enlarge the potential of effector-based selection
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Valls, Vidal Cristina. "Aplicació de nous sistemes enzimàtics pel blanqueig de pasta kraft d'eucaliptus." Doctoral thesis, Universitat Politècnica de Catalunya, 2008. http://hdl.handle.net/10803/6496.
Full textAbstract:
La tesi que ens ocupa, parteix de I'interes de blanquejar pasta kraft d'eucaliptus a traves de tecnologies netes, es a dir, utilitzant metodes mes respectuosos pel medi ambient. La motivacio per a la realitzacio d'aquesta tesi, sorgeix de la problematica ambiental ja coneguda que existeix amb relacio a la contaminacio produida pels reactius utilitzats en el blanqueig de pastes per a paper i de I'interes estrategic que representa per Espanya la utilitzacio de la fusta d'eucaliptus. D'aquesta manera, es volen estudiar nous sistemes enzimatics que puguin deslignificar i blanquejar aquesta pasta.La present tesi s'emmarca dins d'una de les linees d'investigacio del Departament d'Enginyeria Textil i Paperera, de la Universitat Politecnica de Catalunya, encaminada a ('Aplicacio de la Biotecnologia per al Blanqueig de Pastes.
Aixi, s'enfoca la recerca cap a la utilitzacio de xilanases per a potenciar el blanqueig en sequencies ECF i TCF, i cap a la utilitzacio de lacases a traves del sistema lacasa-mediador per a blanquejar i deslignifcar la pasta. Degut al gran contingut en acids hexenuronics de les pastes kraft d'eucaliptus, i a la creixent importancia d'aquests en els processos de blanqueig, especial interes es dona en la seva evolucio al Ilarg dels diferents tractaments.
Primerament es realitza un escrutini d'actuacio de diferents xilanases tant noves com comercials per tal d'identificar les mes eficients en potenciar el blanqueig. Aquests assajos es realitzen sobre sequencies XD, XP i XDP. Segons les propietats de la pasta d'index kappa, blancor, viscositat i HexA i segons I'analisi per cromatografia en capa fina dels efluents de I'etapa X, s'obte que la xilanasa comercial Xc i que la xilanasa nova XG son les mes eficients en potenciar el blanqueig. La xilanasa nova mes eficient pertany a la familia 11 de les glicosil hidrolases. D'altra banda, s'observa que la xilanasa XJ (familia 5) produeix Ileugers efectes sobre les pastes i que totes les xilanases noves (families 10, 11 i 5) contribueixen a la disminucio del contingut en HexA de les pastes.
Seguidament, la millor xilanasa comercial (Xc) i nova (XG) s'apliquen en una sequencia complerta de blanqueig XDEopD1. Degut a I'interes cientific que representa aplicar per primera vegada una xilanasa de la familia 5 sobre les pastes, tambe s'aplica la xilanasa Xj en aquesta sequencia complerta. La xilanasa Xj s'aplica sola i combinada amb la xilanasa XG. Els resultats demostren que amb un pretractament amb xilanasa es milloren les propietats de les pastes al Ilarg de la sequencia i que el pretractament X podria permetre un estalvi en dioxid de clor. A mes, les xilanases no afecten a les propietats fisiques finals dels papers.
En segon Iloc, s'aplica el sistema lacasa-mediador (L) sobre les pastes utilitzant HBT com a mediador. L'objectiu d'aquest tractament es d'una banda optimitzar les condicions d'aplicacio del sistema lacasamediador segons les propietats d'index kappa i blancor i d'altra banda veure si el pretractament amb xilanasa es capag de potenciar I'efecte del tractament L. Tambe es vol analitzar com el tractament L afecta als HexA, a la lignina i a la viscositat. Els resultats demostren que a dosis baixes de mediador i a temps curts s'obtenen bones propietats. El tractament L disminueix sobretot la lignina de la pasta tot i que tambe fa disminuir els HexA, i Ileugerament la viscositat. Els esterols de la pasta son tambe eliminats durant aquest tractament. A mes, es demostra que el pretractament X "facilita" I'efecte del sistema lacasa-mediador en eliminar els acids hexenuronics de la pasta. Per I ltim, queda reforgada la necessitat d'aplicar una etapa d'extraccio alcalina posterior a L.
Posteriorment, es compara I'efectivitat del mediador NHA respecte I'HBT obtenint resultats molt prometedors amb aquest mediador ja que a part de ser mes barat i potencialment menys toxic que I'HBT, presenta una reaccio de tipus reversible i es tant eficient com aquest I ltim en deslignificar la pasta. Paral·lelament es realitza una recerca de mediadors naturals produits durant el creixement de P.cinnabarinussobre la fusta de pi. Per I ltim, s'aplica per primera vegada la tirosinasa en el blanqueig de pastes i els resultats indiquen que cal continuar la recerca sobre aquesta possible aplicacio biotecnolOgica d'aquest enzim. Aquest bloc d'experiencies s'ha realitzat a l'"Institut National de la Recherche Agronomique" (INRA) de Marsella, Franca.
Finalment, es discuteix sobre la importancia dais acids hexenuronics al Ilarg dais processos de blanqueig, i sobre com aquests son eliminats pals diferents tractaments tant quimics corn enzimatics. Es troba la relacio antra aquests acids i I'index kappa de la pasta d'eucaliptus utilitzada.
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Bosch, i. Suades Carme. "Contaminació per compostos orgànics persistents en el sistema fluvial del riu Ebre." Doctoral thesis, Universitat de Barcelona, 2009. http://hdl.handle.net/10803/2741.
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Els compostos orgànics persistents (COPs) són tòxics, persistents, bioacumulables, tenen una gran estabilitat química i capacitat per distribuir-se per tot el planeta. La contaminació per aquests compostos en diversos trams del riu Ebre és molt elevada en comparació als nivells descrits a la Península Ibèrica i en sistemes d'aigües continentals del món, principalment a causa de l'activitat de les plantes clor-àlcali de Flix (província de Tarragona) i Montsó (província d'Osca). Aquesta tesi estudia l'impacte que les plantes clor-àlcali de Flix i Montsó han tingut en el tram baix de la conca del riu Ebre. Primerament avalua la dispersió atmosfèrica dels contaminants emesos a Flix. En segon lloc estudia la mobilitat dels sediments contaminants dipositats a l'embassament de Flix aigües avall del riu i l'impacte en l'activitat agrícola d'aquest tram de riu. Finalment caracteritza els residus de DDT del tram baix de la conca del riu Ebre i determina l'origen d'aquest pesticida, actualment prohibit a l'Estat espanyol.
Dispersió atmosfèrica de contaminants emesos per la planta de Flix (Capítol 2)
S'ha avaluat la dispersió atmosfèrica de COPs mitjançant l'anàlisi d'aquests contaminants en vegetació. S'ha observat que l'activitat industrial que es desenvolupa a Flix actua com a font de contaminació atmosfèrica de COPs. S'ha obtingut un model de distribució per a cada contaminant que ha permès determinar un radi d'influència per a cadascun d'ells. La dispersió de cada contaminant va estretament lligada a les seves propietats físico-químiques.
Impacte de la planta de Flix en l'activitat agrícola del tram baix de la conca del riu Ebre (Capítol 3)
S'ha estudiat el contingut de COPs en 85 finques agrícoles regades amb aigua del riu Ebre des de Flix fins a la desembocadura i s'ha avaluat la transferència de COPs d'aquests sòls a la part comestible dels productes agrícoles que s'hi cultiven. S'han observat nivells de COPs en els sòls agrícoles molt variables però en general les concentracions són baixes. Els sòls amb nivells més alts són aquells que estan situats a prop del llit de riu o bé aquells que es reguen amb quantitats molt elevades d'aigua. La presència de COPs a la part comestible dels productes agrícoles no està directament lligada a la presència de COPs en el sòl a on s'han cultivat. Els nivells de COPs dels productes agrícoles provenen de la incorporació directa de la part aèria de la planta.
Mobilització dels contaminants de l'embassament de Flix aigües avall del riu Ebre (Capítol 4)
S'han analitzat mostres de sediments fluvials del mateix embassament de Flix i d'aigües avall fins al Delta de l'Ebre. S'han observat concentracions molt altes de tots els COPs estudiats excepte els HCHs als sediments de l'entorn de Flix i en cap cas s'observa una disminució de les concentracions respecte les campanyes anteriors. Existeix mobilització i transport dels sediments contaminats de Flix aigües avall d'aquest punt i s'han mantingut constants durant aquest període de temps.
Origen dels residus de DDT de la conca del riu Ebre (Capítol 5)
El DDT és un producte sintètic amb propietats insecticides. El seu ús i producció està restringit des de la dècada dels 70, encara que la prohibició total a l'Estat espanyol no va tenir lloc fins l'any 1994. Tanmateix, actualment encara es detecten quantitats importants de DDT i els seus productes de degradació, DDE i DDD, en sòls, aire, aigua, etc. S'han analitzat els nivells dels isòmers de DDT en mostres de sòls i sediments del tram baix de la conca del riu Ebre per tal de fer una caracterització d'aquests residus. A més s'ha determinat la composició enantiomèrica de l' o,p'-DDT d'aquests sòls per conèixer el seu estat de degradació. S'han identificat almenys dues fonts de contaminació per DDTs relacionades amb l'activitat industrial de Flix i Montsó. A més a més s'han identificat àrees amb aportacions recents de DDT, algunes d'elles relacionades amb l'ús de l'acaricida dicofol.
Persistent Organic Pollutants (POPs) are compounds which have shown to be toxic, persistent, bioaccumulable in animals and humans and with capacity of worldwide atmospheric transport, reaching remote areas where they have never been produced or used. In some specific areas such as the Ebre river basin, contamination by POPs is very high, mainly due to the industrial activity from two chlorine-alkali plants situated in Flix (Tarragona Province, Catalonia) and Monzón (Huesca Province, Aragón).
The present PhD thesis is devoted to assess the impact that this chlorine-alkali plants has had in the lower course of the Ebre river basin. Firstly it evaluates the atmospheric emissions to the environment from the chlorine-alkali factory in Flix. Secondly it studies the mobilization downstream of the polluted sediments placed in Flix water reservoir and the impact of these industrial discharges in the agricultural soils irrigated with water collected downstream. It must be remembered that agriculture encompasses one of the main uses of river water in the Ebre river basin. Finally, the thesis is addressed to characterize the DDT residues in sediments and soils of the lower course of the Ebre river basin and to determine the origin of this pesticide that is currently banned in Spain.
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Mahmoud, Nawrous Ibrahim. "A Backstepping Design of a Control System for a Magnetic Levitation System." Thesis, Linköping University, Department of Electrical Engineering, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-1960.
Full textAbstract:
The subject of this thesis is the design of a control law for a magnetic levitation system, which in this case is the system 33-210. The method used is backstepping technique and specifically adaptive observer backstepping due to parameter uncertainties and lack of access to all the states of the system. The second state of the system, the speed of the steel ball, was estimated by a reduced order observer. The model used gave us the opportunity to estimate a parameter which in the literature is denoted virtual control coefficient. Backstepping method gives us a rather straight forward way to design the controlling unit for a system with these properties. Stabilization of the closed-loop system is achieved by incorporating a Lypapunov function, which were chose a quadratic one in this thesis. If thederivative of this function is rendered negative definite by the control law, then we achieve stability. The results of the design were evaluated in simulations and real-time measurements by testing the tracking performance of the system. The simulation results were very promising and the validations in real-time were satisfying. Note that this has been done in previous studies; the new aspect here is the limitation of the voltage input. The real-time results showed that the parameter estimation converges only locally.
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Mathieu-Demazière, Céline. "Cyclic-AMP signalling in Sinorhizobium meliloti and its role in the control of infection during symbiosis with Medicago." Toulouse 3, 2014. http://thesesups.ups-tlse.fr/2382/.
Full textAbstract:
La légumineuse Medicago sativa établit une symbiose fixatrice d'azote avec la bactérie Sinorhizobium meliloti impliquant la formation d'un organe spécialisé, le nodule, au niveau de la racine de la plante hôte. La formation de nodules fait intervenir un programme complexe de développement impliquant le processus d'organogenèse du nodule, l'infection intracellulaire des cellules de ce dernier, ainsi que des mécanismes de différenciation croisée des deux partenaires. Afin que la symbiose garde son caractère mutualiste, il est nécessaire qu'elle soit régulée négativement. Ainsi la nodulation est contrôlée de manière négative par Medicago via en particulier une boucle de régulation appelée AON. Pour éviter une surinfection racinaire, l'infection est également contrôlée de manière négative. Jusqu'à maintenant, on pensait que seule la plante jouait un rôle dans le contrôle négatif de l'infection. Dans le cadre de ma thèse, nous avons mis en évidence que la bactérie S. Meliloti intervenait également dans ce processus. En effet, nous avons montré que trois adénylate cyclases (ACs)bactériennes de type récepteur, CyaD1, CyaD2, et CyaK, participent au contrôle du processus infectieux en réponse à un signal de nature inconnue. En réponse à ce signal, les trois ACs synthétisent de l'AMPc qui, via le régulateur Clr (CRP-like regulator), active un gène cible, le gène smc02178 dont le rôle est encore inconnu. La mutation des composants de la cascade conduit à un phénotype hyper-infectieux sur les racines de M. Sativa. Mes travaux de thèse ont porté sur la caractérisation du signal perçu par les cyclases, sa biosynthèse et l'étude de son mode de perception par CyaK. Nous avons montré que le signal perçu par les trois cyclases est de nature végétale. Ce signal est présent dans les parties aériennes et dans les nodules de M. Sativa, ainsi que chez un grand nombre d'espèces végétales y compris non légumineuses. Dans un deuxième temps, nous nous sommes intéressés à une phosphodiesterase (PDE), la proteine SpdA (SMc02179), susceptible d'être impliqué dans la régulation du taux d'AMPc présent dans la bactérie. L'étude de la régulation du gène smc02179 codant la PDE a montré que le gène smc02179 est exprimé en symbiose dès le stade précoce de l'infection. Nous avons également caractérisé de manière fonctionnelle la protéine SpdA in vivo et in vitro et étudié son rôle dans la cascade de signalisationThe leguminous plant Medicago sativa (Alfalfa) can enter a symbiosis with a nitrogen-fixing bacterium called Sinorhizobium meliloti. S. Meliloti elicits on M. Sativa roots the formation of specialized organs called nodules that behave as miniature nitrogen-fixing factories in which fixed nitrogen is provided to the plant, in proportion of its needs. Extensive work on the model Medicago truncatula/S. Meliloti has revealed a great deal of the genetic pathway involved in Nod Factor (NF) perception and signal transduction pathway leading to coordinated nodule organogenesis and controlled bacterial infection. The negative control of nodulation and infection is nowadays a very active area of research. Such a negative control is physiologically essential as excessive nodulation and/or bacterial infection would be detrimental to the symbiosis and to plant health. So far only plant (Medicago and Lotus) mutants have been identified that are affected for the control of infection. As part of my PhD thesis, we have shown that the bacterium S. Meliloti is also involved in this process. Indeed, we have shown that three receptor-type bacterial adenylate cyclases (ACs) CyaD1, CyaD2 and CyaK, participate in the control of the infectious process in response to an unknown signal. In response to this signal, the three ACs synthesize cAMP which, via the regulator Clr (CRP -like regulator), activates a target gene, the gene smc02178 whose role is still unknown. The mutation of cascade components leads to a hyper-infectious phenotype on M. Sativa roots. My PhD work focused on the characterization of signal perception mechanisms by the cyclases, its biosynthesis and the study of its perception by CyaK. We have shown that the signal perceived by the three cyclases is a plant signal. This signal is present in shoots and in nodules of M. Sativa, and in a large number of plant species including non-legumes. In a second step, we were interested in a phosphodiesterase (PDE), the protein SpdA (SMc02179), potentially involved in the regulation of cAMP levels in S. Meliloti. The study of the smc02179 regulation showed that the gene is expressed in symbiosis from the early stage of infection. We have thus functionally characterized the SpdA protein in vivo and in vitro and studied its role in the signalling cascade
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Dahlstrand, Christian. "Ground and Excited State Aromaticity : Design Tools for π-Conjugated Functional Molecules and Materials." Doctoral thesis, Uppsala universitet, Fysikalisk-organisk kemi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-173115.
Full textAbstract:
The main focus of this thesis is on the aromaticity of the ground state and electronically excited states of π-conjugated molecules and polymers, as well as how aromaticity is connected to their properties. The electronic structures of polybenzenoid hydrocarbons (PBHs) were explored through density functional theory (DFT) calculations and the π-component of the electron localization function (ELFπ). The study revealed how the π-electronic structure is influenced by the fusion of double bonds or benzene rings to the PBHs. We also demonstrated that the π-electrons of benzene extend to accommodate as much aromaticity as possible when bond length distorted. The aromatic chameleon property displayed by fulvenes, isobenzofulvenes, fulvalenes, bis(fulvene)s, and polyfulvenes were investigated using DFT calculations. The tria-, penta-, and heptafulvenes were shown to possess ionization energies and electron affinities which can be tuned extensively by substitution, some of which even outperform TTF and TCNQ, the prototypical electron donor and acceptor, respectively. The singlet-triplet energy gap of pentafulvenes can be tuned extensively by substitution to the point that the triplet state is lower than the singlet state and thus becomes the ground state. The ELFπ of isobenzofulvene shows that the benzene ring in an electronically excited state can be more aromatic than the corresponding ring in the ground state. We have shown that the 6-ring of [5.6.7]quinarene is influenced by a Hückel aromatic resonance structure with 4n+2 π-electrons in the excited quintet state. The bis(fulvene)s which are composed of a donor type heptafulvene and an acceptor type pentafulvene, retain the basic donor-acceptor properties of the two fragments and could function as compact donor-acceptor dyads. A few of the designed polyfulvenes were found to have band gaps below 1 eV at the PBC-B3LYP/6-31G(d) level. Various 2,7-disubstituted fluorenones and dibenzofulvenes were synthesized and their excited state properties were investigated by absorption spectroscopy and time-dependent DFT calculations. It was found that the 1A → 1B transition of ππ* character can be tuned by substitution in the 2,7-positions. The 2,7-bis(N,N-dimethyl) derivatives of fluorenone and dibenzofulvene displayed low energy transitions at 2.18 and 1.61 eV, respectively, in toluene.
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Pippin, William E. Jr. "Optimizing Threads of Computation in Constraint Logic Programs." The Ohio State University, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=osu1041551800.
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François, Patrice. "Le fibrinogène : contribution dans l'infection sur corps étrangers." Paris 13, 1996. http://www.theses.fr/1996PA132032.
Full textAbstract:
Les staphylocoques reconnaissent certaines proteines plasmatiques adsorbees sur les biomateriaux grace a des recepteurs specifiques appeles adhesines, presents a leur surface. Nous avons etudie la composante d'adherence au fibrinogene de staphylococcus aureus (nommee clfa), qui jusqu'ici n'etait pas caracterisee. En collaboration avec un laboratoire de biologie moleculaire, nous avons selectionne des bacteries mutantes, incapables de former des amas en presence de fibrinogene soluble ou d'adherer au fibrinogene depose sur une surface. L'etude de ces mutants a permis de cloner et de sequencer le gene de l'adhesine du fibrinogene. Dans un circuit extra-corporel de circulation sanguine chez l'animal, nous avons determine que le fibrinogene depose sur les materiaux artificiels stimulait l'adherence bacterienne. Un modele d'endocardite experimentale chez le rat a revele que l'adhesine du fibrinogene favorise la colonisation des valves cardiaques par les staphylocoques. Deux strategies visant a reduire l'adherence ou la colonisation des catheters par les staphylocoques ont ete etudiees: (a) une modification de la surface des catheters en polyurethanne, par un traitement a la polyvinylpyrrolidone, reduisant la deposition des proteines plasmatiques sur les materiaux ; (b) l'impregnation des catheters par des agents antimicrobiens ayant un effet bactericide sur les bacteries adherentes. L'importance des resultats obtenus sur la caracterisation de l'adhesine de s. Aureus au fibrinogene et sa contribution, in vitro et in vivo, a l'attachement bacterien permet d'envisager des strategies anti-adhesives specifiques. Ces strategies pourraient devenir une precieuse alternative aux antibiotiques, surtout en presence de souches multiresistantes a ces composes
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Stein, Alexander. "Porting DotGNU to Embedded Linux." Master's thesis, Universitätsbibliothek Chemnitz, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-66724.
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Programming PLC systems is limited by the provided libraries. In contrary, hardware-near programming needs bigger efforts in e. g. initializing the hardware. This work others a foundation to combine advantages of both development sides. Therefore, Portable.NET from the DotGNU project has been used, which is an implementation of CLI, better known as “.NET”. The target system is the PLCcore-5484 microcontroller board, developed by SYS TEC electronic GmbH. Built upon the porting, two variants to use interrupt routines withing the Portabe.NET runtime environment have been analyzed. Finally, the reaction times to occuring interrupt events have been examined and comparedDie Programmierung für SPS-Systeme ist durch die gegebenen Bibliotheken beschränkt, während hardwarenahe Programmierung einen größeren Aufwand durch z.B. Initialisierungen hat. Diese Arbeit bietet eine Grundlage, um die Vorteile beider Entwicklungsseiten zu kombinieren. Dafür wurde Portable.NET des DotGNU-Projekts, eine Implementierung des CLI, bekannter unter dem Namen “.NET”, benutzt. Das Zielsystem ist das PLCcore-5484 Mikrocontrollerboard der SYS TEC electronic GmbH. Aufbauend auf der Portierung wurden zwei Varianten zur Einbindung von Interrupt-Routinen in die Portable.NET Laufzeitumgebung untersucht. Abschließend wurden die Reaktionszeiten zu eintretenden Interrupts analysiert und verglichen