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Svartsjaern, Mikael. "Footwall stability in SLC mining." Doctoral thesis, Luleå tekniska universitet, Geoteknologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-65420.
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This thesis is based on a case study of the Kiirunavaara sublevel cave (SLC) mine. It focuses on footwall stability and damage development in the mining infrastructure on mine scale. Damage to the infrastructure is mappable for the full height of the footwall by access through decommissioned infrastructure associated with earlier mining stages. Damages range from pure structurally controlled failures (wedge failures) in the upper part of the footwall to fracture growth through intact rock combined with micro‑seismic emissions at the active mining depth. The thesis addresses four distinct research questions; (i) What are the predominant failure mechanisms for the Kiirunavaara footwall? (ii) What is the role of confinement on the damage development in the footwall? (iii) How does the SLC relate to the footwall damage development? (iv) How can infrastructure damage associated to the future mining be estimated using currently available data? Two sets of calibrated numerical models were used to study the damage evolution processes using damage mapping data as the main calibration parameter. Validation of the models was achieved by correlation of model output to micro-seismic locations. The modelling and damage mapping results were used as the basis for the development of a simple prognosis tool for estimating the ultimate extent of infrastructure damage associated to the mining advance for future mining steps. A literature review on slope failure modes, large scale failures in cave mining and failure tracking using micro-seismic locations is included to provide background and definitions. The literature describes principal failure modes as well as mechanism combinations such as structurally controlled failures initiated by deep seated rock mass failures or relaxation. Cases are presented where previously stable structures become destabilised by cave advance and examples where micro‑seismic recordings were used to track deformations and the initiation and growth of newly formed fractures. The Kiirunavaara SLC mine is presented in detail as the main case study of the work. The mine has been in operation since the early 20th century with a transition to underground operation over 50 years ago. The extent of the orebody is 4 km in length with an average width of 80-90 m, the termination at depth has yet to be determined. The ore has an average dip of 60˚ east and a dip-along-strike to the north. Both the footwall and hangingwall rock masses are considered hard and competent with UCS values for the footwall ranging from ca. 130 MPa to extreme cases of 600 MPa. The ore is mined in production blocks about 400 m wide (along strike), Mining of the northernmost blocks, situated in the Lake ore, did not start as open pit operations but has been accessed from the underground via SLC only. The instabilities in the footwall has been addressed by several research studies in the past, with the predominant failure mechanisms in different studies being suggested as large scale tensile failure, complex wedge failure, or rotational shear failure, i.e., some type of principal slope failure. In this work, conceptual numerical models in UDEC were calibrated to fit underground damage mapping data by tracking numerical shear strain concentrations. The conceptual models suggested rock mass damage without the indications of development of large scale slope failure mechanisms such as shear bands. Mine scale PFC models were calibrated with respect to the rock mass strength parameters derived by the conceptual UDEC models and used to study rock mass fracturing in the absence of large scale failure. It is shown that damage to the rock mass occurs mainly close to the active mining in a seismically active zone. This is suggested to weaken and soften the rock mass to allow the development of infrastructure damage in this volume to occur as the rock mass relaxes when entering the stress shadow of the SLC as mining progresses. The damage to the rock mass at the production depth is argued, based on seismic records and a parametric study in UDEC, to constitute of large quantities of local shear failures coalescing to appear as a large scale step-path or rotational shear failure in mapping records. The extent of the associated infrastructure damage is predicated to be limited by the extent of the damaged rock mass zone. A simple bi-linear equation is suggested using ore-width and mining depth as input to estimate the ultimate extent of the damaged zone for each mining stage and thus the limit of later infrastructure damage development. The thesis is concluded with recommendations for future work and potential for continued research.Denna avhandling baseras på en fallstudie av skivrasgruvan Kiirunavaara. Fokus ligger på liggväggstabilitet och skadeutveckling på gruvans infrastruktur i gruvskala. Infrastrukturskador kan karteras längs med hela liggväggens höjd där tillgång till bergmassan ges via urdrifttagna ortar och ramper drivna i samband med tidigare brytningssteg. Dokumenterade skador varierar med djupet – från strukturstyrda brott i den övre delen av liggväggen till ny sprickbildning genom intakt berg kombinerat med mikro-seismik vid nuvarande brytningsdjup. Fyra distinkta forskningsfrågor avhandlas; (i) Vilka är de dominerande brottsmekanismerna i Kiirunavaaras liggvägg? (ii) Vilken roll spelar inspänning för brottsutvecklingen i liggväggen? (iii) På vilket sätt relateras skivrasbrytningen till brottsutvecklingen? (iv) Hur kan skador på gruvans infrastruktur kopplat till framtida brytningssteg uppskattas med data tillgängliga idag? Två omgångar med kalibrerade numeriska modeller togs fram för att studera skadeutvecklingen i liggväggen med skadekarteringsdata som primär kalibreringsparameter. Validering av modellerna uppnåddes genom att studera samstämmigheten mellan modellresultaten och lokaliseringen av mikro-seismiska händelser. Modellresultaten och skadekarteringsdatabasen användes som grund för att utveckla ett enkelt prognosverktyg för att uppskatta den slutgiltiga utbredningen av infrastrukturskador direkt associerade med gruvbrytningen för framtida brytningssteg. En litteraturstudie av släntbrott, storkskaliga brott i samband med rasbrytning samt brottsövervakning med mikro-seismik är inkluderad som bakgrund och för att definiera terminologier som används genom avhandlingen. Literaturstudien beskriver principiella brottsmekanismer samt kombinationer av mekanismer såsom strukturstyrda brott pådrivna av djupt belägna bergmassebrott eller minskad inspänning. Fallstudier presenteras där tidigare stabila strukturer destabiliseras av rasbrytningens framskridande och exempel där mikro-seismikdata använts för att följa deformationer samt initiering och tillväxt av nya sprickor i intakt berg och bergmassa. Kiirunavaaragruvan presenteras i detalj som den huvudsakliga fallstudien för arbetet. Gruvan har varit aktiv sedan tidigt 1900-tal med övergång till underjordsbrytning för över 50 år sedan. Malmkroppens utbredning är 4 km längs strykningen med en genomsnittlig vidd av 80-90 m, och malmkroppens fortsättning mot djupet är öppen. Malmen har en genomsnittlig stupning av 60 grader öst med en fältstupning mot norr. Bergmassan i både liggvägg och hängvägg anses vara hård och kompetent med UCS värden för liggväggen mellan ca. 130 MPa till extrema fall av 600 MPa. Malmen bryts i produktionsblock med ca 400 m bredd (längs malmens strykning). Brytning av de nordligaste blocken, belägna i Sjömalmen, har inte skett i dagbrott utan har utförts enbart via skivrasbrytning. Instabiliteten i liggväggen har avhandlats i ett flertal tidigare studier. De dominerande brottsmekanismerna har föreslagits i tidigare arbeten som storskaligt dragbrott, komplext kilbrott eller cirkulärt skjuvbrott d.v.s. någon typ av principiellt släntbrott. I arbetet för denna avhandling kalibrerades konceptuella numeriska modeller i UDEC mot skadekarteringsdata från liggvägens underjord, med avseende på koncentrationer av skjuvtöjningar. De konceptuella modellerna visade på bergmasseskador utan indikationer på storskaligt släntbrott, exempelvis koncentrationer av numeriska skjuvband. PFC-modeller i gruvskala kalibrerades gentemot bergmasseparametrarna från de konceptuella studierna i UDEC för att direkt studera upprickningen av bergmassan i frånvaro av storskaliga brottsindikationer. Modellerna visade på att skador i bergmassan främst uppkommer nära brytningsområdet i en seismiskt aktiv zon. Detta föreslås försvaga och mjukgöra bergmassan vilket i sin tur leder till utveklingen av infrastrukturskador i den skadade volymen när berget avlastas då området hamnar i spänningsskugga från skivraset. Ovanstående studier visar att skadorna som uppkommer i bergmassan, baserat på de konceptuella UDEC-modellerna och mikro-seismiska data, består av ett stort antal lokala skjuvbrott vilka samverkar till att framstå som ett storskaligt trappstegsbrott eller cirkulärt skjuvbrott i skadekarteringsdatat. Utbredningen av de relaterade infrastrukturskadorna förutspås begränsas av utbredningen av bergmasseskadorna uppkomna vid bryningen. Ett enkelt bi-linjär samband föreslås vilket använder malmbredd och brytningsdjup för att uppskatta den slutgiltiga utbredningen av skadezonen i bergmassan för varje brytningssteg, och i förlängningen begräsningen av senare uppkommande infrastrukturskador. Avhandlingen avslutas med rekommendationer för fortsatt arbete samt framtida forskningspotential.
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Quigley, James A. "A measurement of the tau Michel parameters at SLC." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/45478.
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Damásio, Liliane Isabel Costa. "A problemática da refrigeração de sémen equino." Master's thesis, Universidade de Évora, 2013. http://hdl.handle.net/10174/15976.
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Um número significativo de garanhões produzem ejaculados de baixa qualidade e alta sensibilidade à refrigeração, necessitando de técnicas de processamento especializadas para otimizar a qualidade do sémen. Recentemente, foi disponibilizada uma técnica de centrifugação com monocamada (SLC) de Androcoll-E®, que tem demonstrado selecionar os espermatozoides (SPZ) de boa qualidade. No presente estudo pretendeu-se avaliar o efeito do tratamento com SLC na qualidade do sémen refrigerado, durante 72 horas. As amostras tratadas mostraram valores numéricos superiores para os parâmetros de motilidade, mas apenas se obtiveram valores estatisticamente significativos (p<0,05) para a velocidade curvilínea (VCL) e retilínea (VSL), medidas com um sistema computorizado de análise de sémen, nas amostras tratadas. O reduzido número de amostras e a elevada variabilidade das características seminais entre ejaculados, podem ser responsáveis pela ausência de diferenças estatisticamente significativas, pelo que seria de interesse alargar este estudo a um maior número de garanhões para consolidar as conclusões; ABSTRACT: A significant number of stallions produce ejaculates of low quality and high sensitivity to cooling, requiring specialized processing techniques to optimize the quality of sperm. Recently, a new protocol has been developed - the single layer centrifugation (SLC) with Androcoll-E®, which in some studies has been able to select good quality spermatozoa (SPZ). The objective of this study was to investigate the effect of SLC treatment on the quality of semen refrigerated for 72h. In our study, numerical improvements of motility parameters were seen in the treated samples, but only the curvilinear (VCL) and linear velocities (VSL) measured by a computer analysis system were significantly (p<0.05) higher in the treated samples. Lack of significance may have been due to the small sample size and high variability among ejaculates. Expanding this data set with the use of further ejaculates from different stallions is warranted to draw more definitive conclusions.
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Budd, Chris. "Future of Flash." International Foundation for Telemetering, 2013. http://hdl.handle.net/10150/579690.
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ITC/USA 2013 Conference Proceedings / The Forty-Ninth Annual International Telemetering Conference and Technical Exhibition / October 21-24, 2013 / Bally's Hotel & Convention Center, Las Vegas, NVSolid-State Drives (SSDs) are an enabling technology for data recorders. SSDs can survive where Hard-Disk Drives (HDDs) cannot. SSDs deliver better performance with lower power consumption than HDDs. However, the end of Single-Level Cell (SLC) NAND flash may be near; Multi-Level Cell (MLC) NAND flash soon may be the only choice for industrial applications. System designers have two distinct concerns before implementing SSDs: 1. Cost: MLC NAND flash makes SSDs as affordable as HDDs 2. Endurance: SSDs are reliable and endurance assured with today's controller technology SSDs are leading the charge in transforming data storage in several applications, telemetry included.
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Tverdik, Jaroslav. "Zusammenhang zwischen Opacity Lensmeter 701 und Zeiss SLC-Messsystem zur Quantifizierung der Linsentrübung /." [S.l : s.n.], 1987. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.
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Sreedharan, Smitha. "Functional Characterization of Centrally Expressed Solute Carriers and G Protein-Coupled Receptors." Doctoral thesis, Uppsala universitet, Funktionell farmakologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-156832.
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Transmembrane proteins are gatekeepers of the cells; controlling the transport of substrates as well as communicating signals among cells and between the organelles and cytosol. Solute carriers (SLC) and G protein-coupled receptors (GPCR) are the largest family of membrane transporters and membrane receptors respectively. The overall aim of this thesis was to provide a basic understanding of some of the novel SLCs and GPCRs with emphasis on expression, transport property, evolution and probable function. The first part of the thesis directs towards the study of some novel solute carriers. In an initial study, we provided an overall picture of the sequence relationship and tissue expression of 14 diverse atypical SLCs confirming some of their evolutionary conservation and highly specific expression pattern. The focus then was on the SLC17 family (mainly vesicular proteins) and a novel member named Slc17a9. This study revealed that SLC17 family could be divided into four main phylogenetic clades which were all present before the divergence of the insect lineage with Slc17a9 having the most restricted evolutionary history. Detailed expression study of Slc17a9 in the mouse brain suggests that it is also expressed in some regions important for purinergic neurotransmission. Further, we deorphanised an aminoacid transporter Slc38a7 which was expressed in a majority of neurons in the CNS and showed that it preferably mediate transport of L–glutamine and L–histidine. The second part of the thesis focuses on the study of two GPCRs belonging to the Rhodopsin superfamily, Gpr162 and Gpr153. A phylogenetic analysis revealed that both Gpr153 and Gpr162 originated from a common ancestor before the radiation of the mammalian lineage. Expression study revealed that Gpr162 had a predominant expression in the CNS and relatively lower expression in the other tissue tested whereas Gpr153 had a more widespread and similar expression pattern in both CNS and peripheral tissues. The functional studies of the two GPCRs were done using the antisense oligodeoxynucleotide knockdown rat model. These studies provided evidence linking the orphan Gpr162 gene with the regulation of food intake– related behaviour whereas Gpr153 gene caused only a slight reduction in food intake.
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Heidinger, Michael [Verfasser], and W. [Akademischer Betreuer] Heering. "Long Life Single Stage PFC/SLC Converter driving LEDs / Michael Heidinger ; Betreuer: W. Heering." Karlsruhe : KIT-Bibliothek, 2019. http://d-nb.info/1195049293/34.
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Rodrigues, Alice Cristina. "Efeito da atorvastatina sobre a atividade funcional e expressão de transportadores de membrana do tipo ABC e SLC." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/9/9136/tde-19052009-200620/.
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Os transportadores de membrana do tipo ATP Binding Cassette (ABC) e solute carriers (SLC) regulam a homeostase intracelular de fármacos, modificando a biodisponibilidade e possivelmente a eficácia terapêutica. A variabilidade na resposta a hipolipemiantes, como as vastatinas, tem sido associada a vários fatores genéticos e ambientais. Com a finalidade de avaliarmos os mecanismos de regulação da expressão dos transportadores pela atorvastatina, a expressão de RNAm de transportadores ABC (ABCB1, ABCG2 e ABCC2) e SLC (SLCO1B1, SLCO2B1 e SLC22A1) foi avaliada por RT-PCRq em células mononucleares do sangue periférico (CMSP) de 18 indivíduos normolipidêmicos (NL) e 22 pacientes hipercolesterolêmicos (HC) tratados com atorvastatina (10mg/dia/4 semanas). A possível associação entre o polimorfismo ABCB1 C3435T e a expressão de RNAm também foi avaliada. Os estudos in vitro foram realizados com as células das linhagens HepG2 e Caco-2. Foram avaliados os efeitos da atorvastatina na ativação de fatores de transcrição (NF-kappaB, NF-Y, c-jun, SP-1 e PXR) por ensaio de mobilidade eletroforética retardada em gel de poliacrilamida (EMSA) e na meia-vida do RNAm do gene ABCB1 por RT-PCRq, e a expressão e atividade funcional da proteína ABCB1 por Western blot, imunohistoquimica e citometria de fluxo. A proteina ABCB1 foi localizada por imunohistoquimica na membrana apical do canalículo biliar das celulas HepG2 e na membrana apical das Caco-2. O tratamento das células HepG2 com atorvastatina causou redução da expressão de RNAm do gene ABCB1 e aumento na expressão dos genes ABCG2 e ABCC2. Esses efeitos foram dose e tempo dependentes. O tratamento com atorvastatina das células Caco-2 não modificou a expressão dos transportadores de efluxo após 30 a 120 min. Nas células HepG2, as concentrações de 10 e 20 M de atorvastatina causaram diminuição da expressão de ABCB1 (0 µM: 1,00 ± 0,06; 10 µM: 0,69 ± 0,25, p< 0,05; 20 µM: 0,69 ± 0,06, p< 0,05). A atividade da ABCB1, avaliada pelo efluxo de Rh123, mostrou-se estar reduzida em 41% nas células HepG2, após tratamento com atorvastatina 20 µM. Embora a diminuição da expressão do ABCB1 não tenha sido decorrente de uma menor ativação transcricional, avaliada indiretamente por EMSA, estudos de mecanismos de regulação pós-transcricionais, revelaram que a atorvastatina diminui a estabilidade de RNAm do gene ABCB1. Esse resultado parece estar de acordo com o ocorrido nas CMSP, já que o tratamento com atorvastatina diminuiu a expressão de RNAm do gene ABCB1 nos indivíduos HC. Essa modulação, no entanto não está associada à presença do polimorfismo ABCB1 C3435T. Em relação aos transportadores de captação, a expressão do SLC22A1 nas células Caco-2 diminui após tratamento com atorvastatina por 30 min e não foi modificada nas células HepG2. Já o gene SLCO2B1 encontrou-se muito aumentado após 24 h de tratamento nas células HepG2. Estudos in vivo nas CMSP, mostrou que a expressão de mRNA basal dos transportadores nos HC foi 10 vezes maior que nos NL e diminuiu após tratamento com atorvastatina nos HC. Com os resultados obtidos podemos sugerir que diferenças no efeito da atorvastatina nos tipos celulares podem ser em decorrência da expressão tecido-específica de fatores de transcrição. No modelo de hepatócito, HepG2, a atorvastatina é um inibidor do transporte mediado pela ABCB1 e é capaz de diminuir a síntese e a função da ABCB1, via aumento da degradação de RNAm do gene ABCB1. Em conseqüência ocorre uma redução do efluxo pelo sistema biliar, causando aumento da concentração intracelular. Ainda, podemos concluir que em CMSP o colesterol pode ser o responsável pela modulação dos genes dos transportadores de membrana e que isso pode implicar em diferenças na eficácia da atorvastatina.Specific membrane transporters have a significant impact on drug absorption and disposition. Most of them belong to two super-families, ABC (ATP-binding cassette) and SLC (solute-linked carrier). Statins are important therapeutic agents in the management of hypercholesterolemia, and considerable inter-individual variation exists in response to its therapy. The effects of atorvastatin expression of efflux (ABCG2 and ABCC2) and uptake (SLCO1B1, SLCO2B1 and SLC22A1) drug transporters were investigated by qPCR in Caco-2 and HepG2 cell lines and in peripheral blood mononuclear cells (PBMCs) of eighteen normolipidemic (NL) and twenty two hypercholesterolemic (HC) individuals treated with atorvastatin (10mg/day/4 weeks). The possible involvement of ABCB1 C3435T polymorphism in ABCB1 mRNA expression was also evaluated. In vitro studies with the cell lines HepG2 and Caco-2 were also performed. The effect of atorvastatin on the activation of the promoter of ABCB1 by transcription factors (NF-kappaB, NF-Y, c-jun, SP-1, and PXR) was evaluated by electrophoretic mobility shift assay (EMSA), and ABCB1 mRNA half-life were measured by PCRq. The expression and functional activity of ABCB1 were investigated by Western blot, imunohistochemistry and flow cytometry. Immunohystochemical analysis revealed that ABCB1 is located at the apical membrane of the bile canaliculi in HepG2, and in apical membrane of Caco-2 cells. Atorvastatin treatment of HepG2 cells caused a decreased in ABCB1 and an increase in ABCC2 and ABCG2 transcript levels. These effects were time and dose-dependent. Treatment of Caco-2 cells did not present any differences in efflux transporters mRNA levels. Treatment of HepG2 cells with 10 and 20 M atorvastatin caused a reduction on ABCB1 expression (0 µM: 1,00 ± 0,06; 10 µM: 0,69 ± 0,25, p< 0,05; 20 µM: 0,69 ± 0,06, p< 0,05), and a 41% decrease in ABCB1-mediated efflux of Rhodamine123 (p < 0.01). Although reduced ABCB1 mRNA expression was not due to any repressor protein suppressing ABCB1 promoter activation, mRNA stability studies revealed that mRNA stability of ABCB1 was markedly decreased by atorvastatin treatment (2h versus 7h for control). In agrrement with these results, in PBMCs of HC individuals, atorvastatin treatment also reduced ABCB1 mRNA expression. However, the down-regulation was not associated with the presence of 3435T allele. For the uptake transporters, atorvastatin decreased SLC22A1 transcript levels after 30min-treatment and it was not regulated in HepG2. On the other hand, SLCO2B1 was up-regulated after 24h-treatment of HepG2 cells. In vivo studies with PBMCs revealed that during hypercholesterolemia all the drug transporters analyzed were increased almost 10-fold (p< 0.05), and after atorvastatin therapy the efflux and uptake transporters transcript levels were all down-regulated. These findings suggest that atorvastatin exhibits differential effects on mRNA expression of drug transporters depending on the cell type, which may be related to tissue-specific expression of transcription factors. Atorvastatin leads to decreased ABCB1 function and synthesis in HepG2 cells by increasing degradation of ABCB1 mRNA. Therefore, inhibition of ABCB1 may reduce atorvastatin elimination via bile, increasing its cellular concentrations. We also may suggest that in PBMCs cholesterol modulates mRNA expression of drug transporters, and this may contribute to the variability of response to atorvastatin.
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DELABRE, DANIEL. "$$k2c is infty(s1) et l'extension centrale de segal du groupe des lacets de slc." Toulouse 3, 1998. http://www.theses.fr/1998TOU30137.
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Nous construisons des classes de chern a la beilinson-deligne pour des varietes differentiables lisses ci, j : ki cisinfty(x) isto hd2j-i (x, z(j)) a valeurs dans la cohomologie lisse de deligne, le complexe de deligne lisse etant le meme que son analogue analytique, pour les formes cisinfty. Les proprietes algebriques de ces classes (comportement vis a vis de la multiplication, de la lambda structure et des operations d'adams) proviennent de relations purement algebriques entre les fibres universels, et sont par consequent les memes que celles des classes analogues construites en geometrie algebrique. Nous montrons egalement que c1, 1 est le determinant, d'ou resulte que c2, 2 d'un symbole de steinberg s'exprime comme image inverse du fibre de heisenberg muni de sa connexion. Dans une seconde partie, nous specialisons notre etude a c2, 2. Nous montrons que, pour des varietes compactes, il est possible de deformer infinitesimalement c2, 2 ; cette deformation permet de definir, en utilisant certains resultats de s. Bloch, une extension centrale d'algebres de lie dont un cocycle est y , z ismapsto tr ydz. Pour x = s1, on reconnait la le cocycle de segal. Cela montre que c2, 2s'identifie infinitesimalement au deuxieme regulateur de connes-karoubi c2 ck : $$k2 c isinfty(s1) is to c istimes
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Jones, Hayley. "Antiepileptic drug transport at the blood-brain barrier : the role of the SLC transporter family." Thesis, University of Liverpool, 2014. http://livrepository.liverpool.ac.uk/2010815/.
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The transporter hypothesis has been postulated to explain pharmacoresistance in epilepsy. Despite over a decade of research surrounding the drug transporter hypothesis, the role that solute carrier (SLC) transporters might play in this theory remains largely unaddressed. Hence, the major focus of this thesis was to investigate and identify SLC transporter systems of interest that are expressed at the blood-brain barrier (BBB) and to determine which, if any, of commonly prescribed antiepileptic drugs (AEDs) are substrates for such transporter systems. Characterisation of AED transport was undertaken using widely reported model systems such as Xenopus laevis oocytes and the human cerebral microvascular endothelial cell line (hCMEC/D3), together with novel stably-transfected MDCK II cell lines. Organic anion transporter 1A2 (OATP1A2), the monocarboxylate transporter (MCT) family and the organic anion transporter (OAT) family were specifically selected for investigation. Valproic acid and gabapentin showed the greatest evidence for SLC-mediated transport by OAT1/OAT3 and MCT1 respectively, while other compounds were largely unremarkable in this respect. Valproic acid transport increased OAT1 overexpressing cells compared to control but decreased in OAT3 overexpressing cells. Gabapentin uptake increased in MCT1 transfected Xenopus laevis oocytes and was shown to decrease in hCMEC/D3 cells in the presence of a panel of MCT inhibitors. The induction/suppression of expression of SLC transporters by AEDs was explored in the hCMEC/D3 cell line, in an attempt to understand how AEDs might influence the functionality of endogenous transport pathways. A number of AEDs were observed to induce/suppress expression of transporter genes involved in transport and detoxification. A further study explored the fundamental physiochemical properties of AEDs, which is relevant to their penetration into the brain. A number of AEDs, including lamotrigine, gabapentin and topiramate, observe adequate uptake in the hCMEC/D3 model of the BBB despite having physiochemical properties, such as a high polar surface area and negative log D value which may limit passive entry into the brain. This would suggest that a carrier mediated system may be involved in the uptake of these drugs into the brain. The work described in this thesis has shown that a number of AEDs may be subject to carrier mediated uptake into the brain. Individual differences in transporter expression at the BBB may be responsible for variability in brain concentrations of AEDs. However, at present, this does not provide us with an adequate explanation for why some people with epilepsy experience pharmacoresistant seizures.
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Budd, Chris. "USING MLC FLASH TO REDUCE SYSTEM COST IN INDUSTRIAL APPLICATIONS." International Foundation for Telemetering, 2017. http://hdl.handle.net/10150/626992.
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Storage devices based on Multi-Level Cell (MLC) NAND flash can be found in almost all computer systems except rugged, industrial systems; even though MLC is less expensive and more dense than devices based on standard Single-Level Cell (SLC) NAND flash, MLC’s lower write endurance and lower retention has led system designers to avoid using it. This avoidance is unnecessary in many applications which will never come close to the endurance limits. Furthermore, new processes are leading to storage devices with higher write endurance. System designers should review the specific use-model for their systems and can select MLC-based storage devices when warranted. The result is lower system costs without worry of data loss due to write endurance.
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Roshanbin, Sahar. "Characterization of Centrally Expressed Solute Carriers : Histological and Functional Studies with Transgenic Mice." Doctoral thesis, Uppsala universitet, Funktionell farmakologi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-282956.
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The Solute Carrier (SLC) superfamily is the largest group of membrane-bound transporters, currently with 456 transporters in 52 families. Much remains unknown about the tissue distribution and function of many of these transporters. The aim of this thesis was to characterize select SLCs with emphasis on tissue distribution, cellular localization, and function. In paper I, we studied the leucine transporter B0AT2 (Slc6a15). Localization of B0AT2 and Slc6a15 in mouse brain was determined using in situ hybridization (ISH) and immunohistochemistry (IHC), localizing it to neurons, epithelial cells, and astrocytes. Furthermore, we observed a lower reduction of food intake in Slc6a15 knockout mice (KO) upon intraperitoneal injections with leucine, suggesting B0AT2 is involved in mediating the anorexigenic effects of leucine. In paper II, we studied the postnatal, forebrain-specific deletion of Slcz1, belonging to the SLC18 family, in conditional KO mice (cKO). We observed a decreased response to diazepam and a higher neuronal activity in cortex and hippocampus of cKO mice, as well as an impairment in short-term recognition memory. Intracellular expression was found in neurons but not astrocytes with IHC, indicating SLCZ1 is implicated in neuronal regulation of locomotion and memory. In paper III, we performed the first detailed histological analysis of PAT4, a transporter belonging to the SLC36 family, involved in the activation of mTOR complex 1 on lysosomes. We found abundant Slc36a4 mRNA and PAT4 expression in mouse brain, using ISH and IHC. We used IHC to localize PAT4 to both inhibitory and excitatory neurons and epithelial cells. We also found both intracellular- and plasmalemmal expression and partial colocalization of PAT4 with lysosomal markers. Lastly, in paper IV, we provided the first tissue mapping of orphan transporter MCT14 (SLC16A14). Using qPCR, we detected moderate to high Slc16a14 mRNA in the central nervous system and kidney. We found widespread Slc16a14 and MCT14 in mouse brain using ISH and IHC. We also found MCT14 to have intracellular and plasmalemmal expression in mainly excitatory but also inhibitory neurons, as well as epithelial cells. We found MCT14 to be most closely related to MCT8, MCT2 and MCT9, suggesting a similar role for this transporter.
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Peters, Marc. "Europäischer Marktbeherrschungstest und US-amerikanischer SLC-Test : eine rechtsvergleichende Gegenüberstellung der europäischen und US-amerikanischen Fusionskontrollpraxis /." Hamburg : Kovač, 2005. http://www.verlagdrkovac.de/3-8300-2149-6.htm.
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Kaufhold, Tim. "Das Eingreifkriterium in der europäischen Fusionskontrolle : der SIEC-Test in Abgrenzung zum Marktberrschungs- und SLC-Test /." Baden-Baden : Nomos-Verl.-Ges, 2007. http://www.gbv.de/dms/zbw/543537412.pdf.
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Kaufhold, Tim. "Das Eingreifkriterium in der europäischen Fusionskontrolle : der SIEC-Test in Abgrenzung zum Marktbeherrschungs- und SLC-Test /." [S.l. : s.n.], 2007. http://www.gbv.de/dms/zbw/543537412.pdf.
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Bambade, Philip. "Réglages optiques des arcs et de la section de focalisation finale du collisionneur linéaire de Stanford (SLC)." Paris 11, 1989. http://www.theses.fr/1989PA112048.
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Dans cette thèse, nous décrivons les méthodes expérimentales qui ont été développées pour régler le transport optique des Arcs et de la Section de Focalisation Finale du Collisionneur Linéaire de Stanford (SLC). Ces réglages sont nécessaires pour maximiser la luminosité, en minimisant les dimensions transversales au point d'interaction, et pour réduire le bruit de fond dans l'expérience. Dans la section de focalisation finale, les réglages sont effectués selon une stratégie qui doit tenir compte d'un dessin optique complexe, basé sur des compensations entre aberrations optiques au second ordre, ainsi que des possibilités de mesurer les faisceaux de quelques microns typiques du SLC. Dans les Arcs, les corrections que nous décrivons on été introduites après le démarrage initail pour réduire la sensibilité aux erreurs, à travers une modification du dessin de l'optique, et pour permettre des réglages du faisceau à l'injection de la section de focalisation finale, grâce à une technique de perturbation harmonique inspirée des accélérateurs circulaires. Bien que l'optimisation globale du SLC ne soit pas entièrement achevée, un réglage presque optimal de ces deux lignes a été obtenu. Au point d'interaction des faisceaux avec des dimensions proches des dimensions nominales de quelques microns ont été produits. Nous présentons et discutons les résultats et les limites optiques au fonctionnement actuelIn this thesis, we present the experimental tuning procedures developed for the Arcs and for the Final Focus Section of the Stanford Linear Collider (SLC). Such tuning is necessary to maximize the luminosity, by minimizing the beam size at the interaction point, and to reduce backgrounds in the experiment. In the Final Focus Section, the correction strategy must result from the principles of the optical design, which is based on cancellations between second order aberrations, and on the ability to measure micron-size beams typical of the SLC. In the Arcs, the corrections were designed after the initial commissionning, to make the system more error-tolerant, through a modification in the optical design, and to enable adjustments of the beam phase-space at the injection to the Final Focus System, through a harmonic pertubation technique inspired from circular accelerators. Although the overall optimization of the SLC is not entirely finished, an almost optimal set up has been achieved for the optics of the Arcs and of the final focus section. Beams with tranverse sizes close to the nominal ones, of a few microns, have been obtained at the interaction point. We present and discuss our results and the optical limits to the present performance
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Ivanova, Svilena. "Glycoprotéines d'enveloppes (Env) des gamma- et delta-rétrovirus et leurs récepteurs : recherche chez les mammifères de nouveaux récepteurs d'Env associés au métabolisme cellulaire et d'Env endogènes apparentées." Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTT052.
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Couverture)Les rétrovirus sont des virus enveloppés à ARN simple brin omniprésents dans le monde animal et sources de nombreuses pathologies. Les rétrovirus de vertébrés comprennent sept genres dont les gamma et deltarétrovirus qui sont l’objet de ces travaux. Les rétrovirus dits endogènes (ERV), par opposition à leurs homologues infectieux exogènes, sont présents dans les cellules germinales et font partie intégrante du patrimoine génétique, avec transmission mendélienne. Au cours de l'évolution, les ERV ont fait l'objet de mutations, rendant défectives la plupart des copies dans les génomes de vertébrés, avec quelques exceptions notoires. De fait, certaines copies maintiennent de larges cadres de lecture suite à une pression de sélection positive.Rétrovirus exogènes et ERV partagent une organisation génétique similaire. Leurs glycoprotéines d’enveloppe (Env), dont une des propriétés est de lier un récepteur cellulaire, comprennent une composante de surface (SU) associée à une partie transmembranaire (TM). La SU des Env γ et -rétrovirales porte un module RBD (Receptor-Binding Domain) qui lie un récepteur appartenant à la famille SLC (Solute Carriers) des transporteurs de nutriments. Les SLC présents à la surface cellulaire conditionnent le métabolisme des cellules. Afin de pallier l'absence d'anticorps fiables reconnaissant les parties extracellulaires (exofaciales) des SLC, le laboratoire a dérivé des RBD solubles comme ligands des SLC, permettant de suivre leur expression à la surface cellulaire et ainsi, évaluer le métabolisme cellulaire.Parmi les ERV, certaines env partiellement ou entièrement conservées jouent un rôle physiologique essentiel dans les organismes qui les portent. Une hypothèse de mon laboratoire d’accueil est l’existence de RBD endogènes de mammifères capables de moduler le métabolisme cellulaire de leurs hôtes. Dans ce contexte, mes travaux sont articulés autour de deux axes : (i) identifier et produire de nouveaux RBD dérivés des ERV et (ii) identifier de nouveaux transporteurs de type SLC reconnus par des RBD issus de rétrovirus exogènes et ERV de mammifères. Nous avons identifié et caractérisé deux nouveaux RBD humains endogènes (HERV-41 et HERV-89), entrés et conservés chez les primates de l’Ancien Monde il y a environ 35 millions d’années. Nous avons caractérisé leurs séquences PBS (Primer Binding Site), amorces putatives de la réplication rétrovirale, comme étant complémentaires de l’ARNtLeu ou ARNtArg pour HERV-89, et de l'ARNtGlu pour HERV-41. Les séquences env les plus proches dans le génome humain présentent respectivement 38% et 69% d'identité, indiquant l'appartenance de HERV-89 à deux nouvelles familles d'Env. Nous avons pu produire le RBD soluble de HERV-89, montrer que son récepteur est distinct de l'Env HERV ayant la séquence la plus homologue, et étudier sa distribution tissulaire. Le RBD HERV-89 lie un récepteur sur de nombreuses cellules souches et lignées cellulaires établies et nous avons montré par immunohistochimie que le récepteur est exprimé de manière différentielle dans les tissus humains sains et tumoraux. Parallèlement, nous avons dérivé une banque d'expression de 170 SLC que nous avons utilisée pour le criblage à haut-débit de récepteurs des Env gamma et deltarétrovirales. Cette banque nous a permis d'identifier le récepteur, longtemps recherché, de l’Env du virus de la leucémie bovine (BLV). De plus, en utilisant la transfection d'une banque d’expression d’ADNc dans des cellules de hamster, nous avons aussi identifié le récepteur du virus endogène félin ERV-DC14/FeLV-D comme étant le transporteur de cuivre et de cisplatine CTR1/SLC31A1.L’identification du récepteur de BLV pourrait notamment aider dans la lutte contre la transmission du virus et les pathologies associées qui affectent environ 5% du bétail infecté. De plus, les BLV-RBD et DC14-RBD constituent respectivement de nouveaux marqueurs et modulateurs potentiels du métabolisme, dont celui du cuivreRetroviruses are enveloped, single-stranded RNA viruses, that are omnipresent in animals and the causal agents of a large array of pathologies. Vertebrate retroviruses are divided into seven genera, including the γ and -retroviral groups, which we study particularly. Endogenous retroviruses (ERV), as opposed to exogenous infectious viruses, are present in germline cells and as such are bona fide components of the host genome, with Mendelian transmission. Most ERV have been inactivated by purifying mutations during evolution, although a few copies have been subjected to positive selection pressure with conserved open reading frames (ORFs).Exogenous viruses and ERV that belong to gamma and deltaretroviruses share similar genetic organization and their envelope glycoproteins (Env) comprises a transmembrane (TM) and a surface (SU) component, which binds a specific receptor on the host cell membrane. The SU contains a receptor-binding domain (RBD), responsible for receptor recognition, while TM engages membrane fusion and harbors an immunosuppressive domain. Noticeably, some ERVs have maintained entire or partial ORFs in env, which have been shown, in certain cases, to have essential physiological functions.Another common feature of gamma and deltaretroviral Env is the nature of their receptors, which, when identified, all belong to the solute carrier family of nutrient transporters (SLCs). The laboratory derived soluble RBDs from complete Env that can bind cognate receptors and be used to monitor SLC receptor expression at the cell surface. This important property of RBDs overcomes the notorious lack of reliable anti-SLC exofacial antibodies and provides a new way to evaluate, or even modulate, cell metabolism.Our laboratory postulates that some endogenous RBD-coding genes have been positively selected in their hosts for properties linked to binding SLCs and modulating host cell metabolism. In this context, the aim of my work was to: (i) search for new natural endogenous RBDs and (ii) characterize SLC transporters recognized by RBDs derived from ERVs or exogenous infectious mammalian retroviruses.Here, we describe the identification of two novel human endogenous RBDs (HERV-41 and HERV-89), which each harbor a significant ORF. We estimated that both RBDs have been introduced into Old World primate genomes 35 MYA ago, after the separation with New World monkeys. HERV-89 and HERV-41 are included within retroviral elements that comprise potential primer binding sites (PBS) complementary to tRNALeu or tRNAArg, for HERV-89, and tRNAGlu, for HERV-41. The envs of HERV-89 and HERV-41 do not share more than 38% and 69% amino acid identity with the closest known HERVs, respectively, which indicates that they belong to two new Env families. We derived a soluble HERV-89 RBD and monitored its receptor cell and tissue distribution. Using the ligand by flow cytometry, we observed that a HERV-89 receptor is expressed in a large panel of established cell lines and stem cells. Immunohistochemistry on 94 healthy and tumor human tissue samples showed that HERV-89 receptor is largely distributed, with distinct expression patterns in healthy and tumor tissues. In parallel, we derived a 170 gene-containing SLC expression library for high throughput screening of SLC/ligand interactions. Using this partial human SLC library, we identified the long-sought receptor for bovine leukemia virus (BLV). Moreover, transfection of a cDNA library expression into hamster cells, led us to identify CTR1/SLC31A1, the copper and cisplatin transporter, as the receptor for the feline ERV-DC14/FeLV-D.As a ligand for the BLV receptor, BLV-RBD may be used to help controlling BLV transmission and prevent associated pathologies that affect 5% of infected cattle. Also, BLV-RBD and DC14-RBD can now be used as metabolic markers and modulators of their SLC cognate receptors, including copper metabolism, in the case of DC14-RBD
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吉松, 宏樹. "リボフラビントランスポータRFVT3(SLC52A3)の生理的役割に関する研究." 京都大学 (Kyoto University), 2014. http://hdl.handle.net/2433/188734.
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Raciti, Daniela. "A large-scale gene discovery screen identifies over hundred solute carrier (SLC) genes with organ specific expression patterns in the Xenopus embryo /." Zürich : ETH, 2007. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17204.
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Höglund, Pär J. "Identification, Characterization and Evolution of Membrane-bound Proteins." Doctoral thesis, Uppsala universitet, Institutionen för neurovetenskap, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-9329.
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Membrane proteins constitute approximately 30% of all genes in the human genome and two large families of membrane proteins are G protein-coupled receptors (GPCRs) and Solute Carriers (SLCs) with about 800 and 380 human genes, respectively. In Papers I, II and IV, we report 16 novel human Adhesion GPCRs found by searches in NCBI and Celera databases. In Paper I, we report eight novel human GPCRs, and six in Paper II. We identified two new human Adhesion GPCRs and 17 mouse orthologs in Paper IV. Phylogenetic analysis demonstrates that the 16 novel human genes are additional members of the Adhesion GPCR family and can be divided into eight phylogenetic groups. EST expression charts for the entire repertoire of Adhesions in human and mouse were established, showing widespread distribution in both central and peripheral tissues. Different domains were found in their N-terminus, some, such as pentraxin in GPR112, indicates that they take part in immunological processes. In Paper III, we discovered seven new human Rhodopsin GPCRs. In Paper V, we present the identification of two new human genes, termed SLC6A17 and SLC6A18 from the Solute Carriers family 6 (SLC6). We also identified the corresponding orthologs and additional genes from the mouse and rat genomes. We analysed, in total, 430 unique SLC6 proteins from 10 animal, one plant, two fungi and 196 bacterial genomes. In Paper VI, we provide the first systematic analysis of the evolutionary history of the different SLC families in Eukaryotes. In all, we analysed 2403 sequences in eight species and we delineate the evolutionary history of each of the 46 SLC families.
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Valade, Cédric. "Compression d'images complexes avec pertes : application à l'imagerie radar." Phd thesis, Télécom ParisTech, 2006. http://pastel.archives-ouvertes.fr/pastel-00002064.
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Installé à bord d'aéronefs ou de satellites, le Radar à Synthèse d'Ouverture (RSO) permet d'imager des zones à haute résolution. Les volumes de données générés sont très importants et les capacités limitées des canaux de transmission et/ou de stockage forment un sous-ensemble critique des systèmes d'observation. De ce fait, la solution classiquement retenue est de recourir à la compression des données. Le système radar cohérent génère des données de forte dynamique où les pixels issus de la formation de l'image sont des données complexes au sens mathématique du terme, c'est-à-dire constitués d'une valeur d'amplitude et de phase. La faible corrélation spatiale des pixels rend les techniques de compression répandues dans le domaine optique beaucoup moins efficaces. L'objectif de cette étude consiste à proposer un système de compression avec pertes adapté aux images RSO SLC (Single Look Complex) et prenant en compte le caractère complexe des pixels. Nous suggérons différents schémas de compression dépendants de la répresentation du signal dans le plan complexe (amplitude/phase ou partie réelle/imaginaire). Nous nous focalisons essentiellement sur des techniques de type multirésolution comme la transformée en ondelettes et paquets d'ondelettes discrètes. Un ensemble de modèles statistiques spécifiques à la caractérisation des images RSO permettra d'adapter diverses méthodes de quantification polaire à la problématique de la compression d'images complexes. Enfin, la dernière partie de cette étude sera consacrée à la présentation des résultats à traver l'utilisation d'un panel de critères objectifs avec notamment une évaluation de la qualité des images décompressées.
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Pipkin, Alex. "Relacionamentos no mercado internacional : um estudo exploratório da indústria metal-mecânica brasileira e argentina." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 1998. http://hdl.handle.net/10183/1414.
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Em um mundo de intensa competição global, a lógica da colaboração se tornou uma parte essencial da estratégia de negócios. Os relacionamentos entre empresas no mercado internacional, através da colaboração entre firmas parceiras, passam a ser considerados como a chave para o sucesso das metas empresariais das organizações. Aquelas empresas que estabelecerem e cultivarem os benefícios mútuos advindos das parcerias internacionais poderão esperar um desempenho competitivo superior. Nesse contexto, o objetivo central deste estudo é examinar os elementos estimuladores e inibidores do relacionamento entre empresas do setor metal-mecânico automotivo do Rio Grande do Sul/Brasil e da Argentina. Para tanto, a fim de se verificar a presença de tais elementos nas relações de troca no ambiente do Mercosul, a partir de uma abordagem exploratória, empregou-se o método de estudo de casos. Foram investigados três casos de relacionamento entre empresas estabelecidas no Rio Grande do Sul e suas respectivas firmas parceiras no mercado argentino. Foi utilizado o critério de duração de, no mínimo, dois anos de transações de troca entre as partes envolvidas. A presente investigação ocorreu entre os meses de outubro de 1997 e abril de 1998. O estudo apresenta resultados individuais quanto às características de cada relacionamento investigado e uma análise comparada no que diz respeito às motivações e aos aspectos inibidores identificados nas relações de troca estudadas. Por fim, são apresentadas implicações do estudo, que poderiam ser aprofundadas em novas pesquisas na área de relacionamentos nos mercados internacionais, bem como as limitações do referido trabalho.
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Chedik, Lisa. "Nature et conséquences des interactions entre transporteurs membranaires et pesticides." Thesis, Rennes 1, 2017. http://www.theses.fr/2017REN1B035/document.
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Les pyréthrinoïdes et les organophosphorés sont des pesticides très utilisés, à l’origine d’une imprégnation forte de la population, exposée à ces contaminants principalement via l’alimentation. De plus en plus d’études scientifiques suggèrent des liens entre l’exposition à ces composés et des maladies chroniques ou des troubles du développement de l’enfant. Paradoxalement, leur devenir biologique chez l’homme est mal connu. Certaines études suggèrent que ces insecticides sont susceptibles d’intéragir avec les transporteurs membranaires ABC et SLC, protéines localisées au niveau d’interfaces hémato-tissulaires qui prennent en charge de nombreux substrats endogènes, médicaments et contaminants de l’environnement. L’objectif de notre étude a été de caractériser les effets d’insecticides des familles des pyréthrinoïdes et des organophosphorés sur l’activité de nombreux transporteurs ABC et SLC prenant en charge des médicaments (P-gp, BCRP, MRPs, OATP-1B1,-2B1,-1B3, OCT1-3, OAT1, OAT3, MATE1 et MATE2K) par une approche in vitro. Nous nous sommes également attachés à caractériser par des expérimentations in vitro et in silico, les mécanismes des interactions et les éléments structuraux des pesticides à l’origine de ces effets. Nous avons montré que de nombreux organophosphorés et pyréthrinoïdes étaient capables d’inhiber des transporteurs d’efflux (MRP, BCRP, P-gp) et d’influx (OATP1B1, OAT3, MATE1, OCT1-2) et de stimuler l’activité de certains OATPs. Les pesticides testés inhibaient très fortement l’activité des transporteurs de cations (OCT1 et OCT2) et ont pu bloquer le transport de catécholamines médiés par ces protéines. Une approche qSAR a permis de définir des paramètres physicochimiques associés aux effets modulateurs des pesticides et une approche d’amarrage moléculaire (docking) a mise en évidence les sites de liaisons de la P-gp impliquées dans ces interactions. Les conséquences des modulations de l’activité des transporteurs, en termes d’effets toxiques et d’interactions médicamenteuses, restent à définir pour les populations exposées à de fortes doses de pesticides. Toutefois, la contribution des interactions observées aux effets toxiques de ces insecticides est peu probable car nécessitant des concentrations nettement supérieures à celles atteintes dans le cadre d’une exposition environnementale de la population généraleThe general population is chronically exposed to pyrethroids and organophosphorus insecticides, mainly through alimentation. Several epidemiological studies have found an association between non-occupational exposure to these pesticides and chronic diseases and developmental disorders. Paradoxically, their biological fate in humans is poorly understood. Some studies suggest that these insecticides could interact with ABC and SLC membrane transporters. These membrane proteins, located at blood-tissue interfaces (liver, kidney, intestine ...), handle many endogenous substrates, drugs and pollutants. The objective of our study was to characterize, using an in vitro approach, the effects of pyrethroid and organophosphorus insecticides on the activity of numerous ABC and SLC human drug-transporters (P-gp, BCRP, MRPs, OATP-1B1, -2B1, -1B3, OCT1-3, OAT1, OAT3, MATE1 and MATE2K). We have also tried to analyze the mechanisms of interactions and the structural requirements for insecticides-mediated modulation of drug transporters activities using in vitro and in silico approach. We have shown that many organophosphorus and pyrethroids are able to inhibit ABC (MRP, BCRP, P-gp) and SLC (OATP1B1, OAT3, MATE1, OCT1-2) transporters and can stimulate the activity of some OATPs. Moreover, the tested pesticides inhibited very strongly the activity of OCT1 and OCT2 and blocked catecholamine transport mediated by these transporters. A qSAR approach allowed to define physicochemical parameters associated with the modulating effects of pesticides and a molecular docking approach revealed the P-gp binding sites involved in these interactions. The consequences of transporter activitie modulation, in terms of toxic effects and drug interactions, remain to be defined for populations exposed to high doses of pesticides, occurring notably in response to poisoning. However the alterations of these transporter activities by insecticides are unlikely to contribute to organophosphorus or pyrethroids toxicities of chronic low-dose exposure
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Grottker, Julia [Verfasser], Gerhard [Akademischer Betreuer] Burckhardt, Claudia [Akademischer Betreuer] Steinem, and Jürgen [Akademischer Betreuer] Brockmöller. "Expression von SLC-Transportern in Melanomzelllinien und Charakterisierung von MATE1 und OCT1 in ihrer Funktion als Zytostatikatransporter / Julia Grottker. Gutachter: Claudia Steinem ; Gerhard Burckhardt ; Jürgen Brockmöller. Betreuer: Gerhard Burckhardt." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2011. http://d-nb.info/1043939547/34.
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Lê-Bury, Gabrielle. "Infection des macrophages par le VIH-1 : facteurs moléculaires impliqués dans la production virale et dans le développement de bactéries opportunistes The HIV-1 protein Vpr impairs phagosome maturation by controlling microtubule-dependent trafficking Pronounced stealth phenotype and differential pyroptosis induction by invasive Salmonella Typhimurium revealed by coinfection of human macrophages with HIV Role of Solute Carriers in efficient HIV-1 production by human macrophages." Thesis, Sorbonne Paris Cité, 2018. http://www.theses.fr/2018USPCB094.
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Le Virus de l'Immunodéficience Humaine de type 1 (VIH-1) infecte les macrophages. Contrairement aux lymphocytes T CD4+, les macrophages résistent aux effets cytotoxiques du virus et représentent un réservoir pour ce pathogène. Dans ces cellules, le virus est produit et stocké dans un compartiment intracellulaire spécifique appelé VCC (Virus-Containing Compartment). Ce compartiment à pH neutre, transitoirement connecté à la membrane plasmique, reste cependant très peu caractérisé. Par ailleurs, le VIH-1 induit une perturbation des fonctions des macrophages, permettant ainsi le développement de bactéries opportunistes, telles que des souches particulières de Salmonella Typhimurium. Nous avons étudié en particulier des souches de Salmonella Typhimurium invasives non typhiques qui se sont développées, chez des patients séropositifs. Les objectifs de ma thèse ont donc été d'étudier, dans les macrophages primaires humains, les facteurs moléculaires impliqués dans la production du VIH-1 et le développement de souches invasives de Salmonella Typhimurium. Dans un premier temps, j'ai contribué à étudier les effets de l'infection par le VIH-1 sur les fonctions des macrophages. Leur fonction majeure est la phagocytose qui est un mécanisme de défense contre les pathogènes permettant leur internalisation et leur dégradation. Il avait déjà été montré au laboratoire que l'étape d'internalisation était en partie inhibée par le facteur de virulence Nef dans les macrophages infectés. Dans ce travail, nous avons montré que l'infection de ces cellules par le VIH-1 inhibe également la maturation des phagosomes, mais via la protéine virale Vpr. Nous avons aussi mis en évidence que le VIH-1 conduit le macrophage dans en état de pré-activation, mais empêche la cellule de répondre à un stimulus ultérieur comme une surinfection bactérienne. Dans un second temps, j'ai participé à l'étude des coinfections entre VIH-1 et les bactéries Salmonella Typhimurium invasives, qui ont émergé avec l'infection par le virus, en comparaison avec des souches de référence. Ce travail nous a permis de montrer que les bactéries, pour leur survie, n'exploitent pas le compartiment viral dans les macrophages co-infectés. J'ai ensuite observé que la souche invasive de Salmonella Typhimurium induit moins de mort cellulaire par pyroptose qu'une souche de référence. J'ai alors déterminé les voies de signalisation en amont de cette mort cellulaire qui est associée à un mécanisme inflammatoire. Ainsi, j'ai mis en évidence que la souche invasive de Salmonella détourne les mécanismes de pyroptose et survit mieux dans les macrophages, ce qui pourrait expliquer la dissémination observée chez les patients. Enfin, j'ai initié l'étude de nouveaux facteurs cellulaires impliqués dans la production virale par les macrophages. À la suite d'une analyse transcriptomique sur des macrophages primaires humains infectés ou non par le VIH-1, nous avons identifié un nombre important de transporteurs membranaires appelés SLC (Solute Carrier) dont l'expression est modulée par l'infection. Après la sélection de candidats, j'ai pu mettre en évidence que certains de ces SLC étaient importants pour la production virale par les macrophages. En conclusion, l'ensemble de ces travaux contribue à définir comment le VIH-1 infecte les macrophages et diminue leurs fonctions d'activation et de clairance, et comment se développent des bactéries opportunistes pathogènesHuman Immunodeficiency Virus type 1 (HIV-1) infects macrophages. In contrast to CD4+ T cells, macrophages are resistant to the cytotoxic effects of the virus and represent a reservoir for the pathogen. In these cells, the new virions are produced and stored in a specific intracellular compartment called Virus-Containing Compartment (VCC). This non-acidic compartment, transiently connected to the plasma membrane, remains poorly characterized. In addition, HIV-1 induces an alteration of macrophage function, allowing the development of opportunistic bacteria, such as specific strains of Salmonella Typhimurium. In particular, we studied invasive non-typhoidal Salmonella Typhimurium (iNTS) strains that developed in HIV-positive patients. The aims of my thesis have been to identify the molecular factors involved in the production of HIV-1 in primary human macrophages and to study the development of the invasive strains of Salmonella Typhimurium. First, I participed in studying the effects of HIV-1 infection on macrophage function. Their main role is phagocytosis, which is a defense mechanism enabling internalization and degradation of pathogens. It has previously been shown in the host laboratory that in HIV-1 infected macrophages, the internalization step is partially inhibited by the virulence factor Nef. In this work, we have shown that the infection of these cells by HIV-1 also inhibits the maturation of phagosomes, in this case, via the viral protein Vpr. Further, we have demonstrated that HIV-1 leads to a pre-activation state of the macrophage, while preventing the cell from responding to subsequent stimuli, such as bacterial superinfection. Secondly, I studied the coinfections between HIV-1 and an invasive strain of Salmonella Typhimurium that was compared to reference strains. This work demonstrated that bacteria do not hijack the viral compartment for their survival in co-infected macrophages. Additionally, the invasive strain of Salmonella Typhimurium was observed to induce less cell death by pyroptosis than a reference strain. The signaling pathways upstream of this cell death were determined to be associated with an inflammatory mechanism. Hence, it was demonstrated that the invasive strain of Salmonella hijacks the mechanism of pyroptosis to survive in macrophages. This may explain the dissemination observed in patients. Finally, a study of new cellular factors involved in viral production in macrophages was conducted. Following a transcriptomic analysis of human primary macrophages infected, or not, with HIV-1, we identified a large number of membrane transporters called SLC (Solute Carrier) whose expression was modulated by the infection. After selecting some of the candidates for further study, I have demonstrated that some of these SLCs are important for viral production in macrophages. In conclusion, this work contributes to defining how HIV-1 infects macrophages and disturbs their activation and clearance functions, and how opportunistic pathogenic bacteria develop
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Liu, Feng. "Platform Independent Real-Time X3D Shaders and their Applications in Bioinformatics Visualization." Digital Archive @ GSU, 2007. http://digitalarchive.gsu.edu/cs_diss/24.
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Since the introduction of programmable Graphics Processing Units (GPUs) and procedural shaders, hardware vendors have each developed their own individual real-time shading language standard. None of these shading languages is fully platform independent. Although this real-time programmable shader technology could be developed into 3D application on a single system, this platform dependent limitation keeps the shader technology away from 3D Internet applications. The primary purpose of this dissertation is to design a framework for translating different shader formats to platform independent shaders and embed them into the eXtensible 3D (X3D) scene for 3D web applications. This framework includes a back-end core shader converter, which translates shaders among different shading languages with a middle XML layer. Also included is a shader library containing a basic set of shaders that developers can load and add shaders to. This framework will then be applied to some applications in Biomolecular Visualization.
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Navarro, Rosa Jennifer. "Framework for sustainability assessment of industrial processes with multi-scale technology at design level: microcapsules production process." Doctoral thesis, Universitat Rovira i Virgili, 2009. http://hdl.handle.net/10803/8572.
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In a world with limited resources and serious environmental, social and economical impacts, a more sustainable life style is everyday more important. Therefore, the general objective of this work is to develop a methodological procedure for eco-efficiency and sustainability assessment of industrial processes with multi-scale technology at design level. The methodology developed follows the ISO 14040 series for environmental LCA standard. To integrate the three pillars of sustainability the analytical hierarchical process was used. The results are represented in a triple bottom line framework. The methodology was applied to the case study "production of perfume-containing microcapsules" and different scenarios were assessed and compared. Several sustainability indicators were chosen to analyze the impacts. The results showed that this methodology can be used as a decision making tool for sustainability reporting. It can be applied to any process choosing in each case the corresponding set of inventory data and sustainability impact indicators.En un mundo con recursos limitados y graves impactos ambientales, sociales y económicos, un estilo de vida más sostenible es cada día más importante. Debido a esto, el objetivo general de este trabajo es desarrollar un procedimiento metodológico para evaluar eco-eficiencia y sostenibilidad de procesos industriales con tecnología multi-escala a nivel de diseño. La metodología desarrollada sigue la serie ISO 14040 para el medio ambiente. Se utilizó el proceso analítico jerárquico para integrar los tres pilares de sostenibilidad. Los resultados se presentan en un balance triple. La metodología se aplicó al caso de estudio "producción de micro-cápsulas que contienen perfume" y se analizaron y compararon diferentes escenarios. Se seleccionaron diversos indicadores de sostenibilidad para analizar los impactos. Los resultados demostraron que esta metodología puede ser utilizada como herramienta de toma de decisiones y que puede aplicarse a cualquier proceso seleccionando, en cada caso, los datos del inventario y los indicadores.
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Warren, Jeremy Eugene. "Small Learning Communities and High School Academic Success." ScholarWorks, 2016. https://scholarworks.waldenu.edu/dissertations/2905.
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Thousands of students drop out of high school every day in the United States and the repercussions affect more than just the individual. Research on smaller learning communities (SLC) reveals increased student achievement, as well as improved teacher perception of student engagement. Student attendance, grade point average, and standardized test scores have been seen to improve within the SLC. In addition, graduation rates for students enrolled in a SLC have revealed increases, but this research focuses on the SLC as an intervention for any student. The current research targets at-risk students in an educational climate of sparse resources, and an increasing need for clever use of capital. The current research fills this gap by evaluating a SLC developed for and populated solely with students identified as at-risk by collecting data from students enrolled in a SLC and comparing them to a population of similar at-risk students not enrolled in the SLC. A Chi-square analysis was conducted comparing graduation rates, a 1-factor analysis of variance compared state test scores, and a 2-factor mixed analysis of variance was conducted to compare GPA, attendance, and discipline between and within the 2 groups. The alpha level was adjusted per the Bonferroni method to correct for multiple data points on the same sample and resulting in a sample size of 106. Findings from this research found a one year SLC intervention made a difference in school attendance, and revealed an overall trend of difference between SLC and control at-risk students in all other areas. These findings contribute to positive social change understanding a one year SLC intervention is capable of improving attendance as well as producing an overall positive trend for at-risk high school students in the areas of graduation, standardized assessment, discipline, and standardized assessments.
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Brenner, Christiane. "Dissecting peptidoglycan trafficking and transport(ers) in human cells." Thesis, Sorbonne Paris Cité, 2018. http://www.theses.fr/2018USPCB240.
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Les fragments du peptidoglycane, les muropeptides muramyl-triDAP (MTP) et le muramyl dipeptide (MDP) sont détectés spécifiquement par les récepteurs cytosoliques du système immunitaire inné, Nod1 et Nod2, respectivement. Mais à ce jour, l’internalisation cellulaire de ces fragments, et plus particulièrement dans les cellules du colon humain, reste mal connue. Dans le but de mieux comprendre ce processus d’internalisation cellulaire, une lignée de cellules humaines du colon HT-29 a été utilisée comme modèle. Les deux récepteurs, Nod1 et Nod2 ont été décrits comme étant exprimés dans cette lignée cellulaire, ainsi que la famille du “Solute Carrier 15A“ (SLC15A) connue pour être impliquée dans le transport des MDP et MTP dans d’autres systèmes cellulaires, mais ce qui ne semble pas être le cas dans notre lignée modèle. A titre d’exemples, SLC15A1 (PEPT1) et SLC15A2 (PEPT2) sont exprimés à l’apex des cellules et transportent, en général, des di-et tripeptides dans les cellules intestinales et rénales. Les transporteurs SLC15A3 (PHT2) et SLC15A4 (PHT1) quant à eux, seraient responsables du transport des MDP et MTP, respectivement, dans les endosomes et les lysosomes. L’objectif de cette thèse était d’identifier le mécanisme d’internalisation du MDP dans les cellules HT-29. Ainsi, différents inhibiteurs des voies d’endocytose ont été utilisés dans des expériences de microscopie. Nos résultats suggèrent que la voie d’internalisation est différente de celle utilisée par la transferrine. En effet, l’internalisation du MDP est partiellement dépendante de la dynamine, une GTPase, et des protéines Rac1/Cdc42, deux Rho GTPases. Ces trois protéines sont impliquées dans l’endocytose et Rac1 joue également un rôle dans l’immunité innée. En parallèle, nous avons inactivé le gène MFSD3 par la technique CRISPR-Cas9. Ce dernier est l’homologue du gène ampG d’Escherichia coli qui transporte spécifiquement les muropeptides anhydres. MFSD3 a été proposé comme un autre transporteur de muropeptides, comme le MTP, permettant leur accès à Nod1 et Nod2. Ainsi, nous avons étudié la fonction de MFSD3. Les cellules déplétées pour MFSD3 étaient affectées dans leur prolifération et dans l’accumulation d’Acetyl-CoA. Une étude protéomique a montré l’implication de MFSD3 dans plusieurs voies de signalisation, suggérant son rôle important dans le métabolisme et, plus largement, dans l’immunitéIn the past it has been found that the peptidoglycan fragments muramyl dipeptide (MDP) and muramyl-triDAP (MTP) are specifically recognized by the cytosolic immune receptors Nod2 and Nod1, respectively. However, it is not clear, especially in intestinal and colon epithelial cells, how these fragments are internalized. HT-29, a human cell line from the colon has been stimulated with MDP-Rhodamine to decipher its uptake mechanism. HT-29 poses an interesting model for studying since it is a colonic cell line and both NOD1 and NOD2 are endogenously expressed, while the Solute Carrier Family SLC15A, that has been associated in the past with internalization of both MDP and MTP, seems to be expressed within these cells, however the transporters do not seem to have a role in transport of these fragments in this cell model. SLC15A1 (PEPT1) and SLC15A2 (PEPT2) are expressed at the apical side of cell membranes and mediate the uptake of di- and tripeptides into intestinal and renal cells, while SLC15A3 (PHT1) and SLC15A4 (PHT1) are assumed to be transporting MDP and MTP, respectively, from the early endosome and from the lysosome. One aim of this thesis was to identify the uptake-mechanism for MDP within these cells. By using different inhibitors of endocytosis in combination with microscopy, it has been found that MDP conjugated to Rhodamine is partly endocytosed by an uptake mechanism dependent on Dynamin and Rac1, two Rho GTPases. These two proteins are both involved in endocytosis and vesicular trafficking. Rac1 many different cellular processes such as gene transcription, vesicle trafficking and cytoskeleton architecture, as well as immune signaling. In addition, CRISPR-Cas9 was applied by a collaboration of the lab to knock-down MFSD3, the human homologue of the AmpG gene in E. coli that has been found to recycle murein tripeptide and transport anhydrous muropeptides required to have the disaccharide N-acetylglucosamine-N-acetylmuramic acid (GlcNac-MurNAc). It was suggested in the literature that MFSD3 thus could be another likely candidate to transport ligands to NOD1. Therefore, it was investigated what the substrate, and in general the function of MFSD3 could be. A proteomics approach was carried out and by this several interesting signaling pathways could be identified that suggest that the gene is likely to be important in metabolism and immunity
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Meghnous, Ahmed Rédha. "Commande et observation d'une classe de systèmes linéaires à commutations : Application aux convertisseurs de puissance DC-DC." Phd thesis, INSA de Lyon, 2013. http://tel.archives-ouvertes.fr/tel-01015252.
Full textAbstract:
Cette thèse s'intéresse à la commande et l'observation d'une classe de systèmes linéaires à commutations (SLC). La classe considérée regroupe les systèmes pouvant être représentés par un modèle Hamiltonien à ports. Récemment, plusieurs travaux ont utilisé la théorie des systèmes dynamiques hybrides pour traiter les problèmes de stabilité, de commandabilité et d'observabilité des systèmes linéaires à commutations. Cependant, certains verrous scientifiques demeurent et nécessitent d'être levés tels que la synthèse d'observateurs pour des SLC présentant des modes de fonctionnement inobservables ou la commande hybride de systèmes possédant un nombre réduit d'entrées de commutations et un nombre élevé de variables d'état à contrôler. Dans ce travail, nous nous intéressons à la synthèse d'observateurs s'appuyant sur la modélisation moyenne et la modélisation hybride de SLC ayant une topologie Hamiltonienne à ports particulière. Ce formalisme possède les outils nécessaires pour établir des preuves de stabilité des erreurs d'observation. Dans un premier temps, nous proposons un observateur non linéaire reposant sur le modèle moyen de la classe des SLC considérée. Ensuite, nous traitons le problème de synthèse d'un observateur hybride où nous proposons un observateur commuté prenant en compte les modes de fonctionnement inobservables. Le problème de la commande des SLC est abordé par la suite. Au départ, la théorie de Lyapunov est utilisée pour proposer deux lois de commandes : La première est synthétisée à partir du modèle moyen et la deuxième exploite le modèle hybride. Une commande optimale hybride est élaborée en utilisant le principe du maximum de Pontryagin et une approche utilisant la recherche d'arcs singuliers. Finalement, une commande prédictive hybride est établie à partir d'un modèle discrétisé du système. Des résultats de simulation et une mise en œuvre expérimentale sur un convertisseur DC-DC SEPIC sont donnés pour montrer l'efficacité des méthodes proposées. L'étude d'un tel circuit est motivée par sa topologie particulière qui contient à la fois un mode de fonctionnement observable et un mode de fonctionnement inobservable. En outre, il possède une seule entrée de commutations et quatre variables d'état ce qui lui vaut la réputation être difficile à commander.
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Matsson, Elin. "In vivo Pharmacokinetics of Two New Thrombin Inhibitor Prodrugs : Emphasis on Intestinal and Hepatobiliary Disposition and the Influence of Interacting Drugs." Doctoral thesis, Uppsala universitet, Institutionen för farmaci, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-123419.
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Biliary excretion is an important elimination route for many drugs and metabolites. For such compounds, it is important to know the extent of excretion and drug exposure in the bile, e.g., for the risk assessment of drug interactions, liver toxicity and the effects of genetic variants. In this thesis, duodenal aspiration of bile was performed in healthy volunteers and complemented with experiments in an in vivo model in pigs to increase the understanding of the intestinal and hepatobiliary disposition of two direct thrombin inhibitors. The compounds investigated, ximelagatran and AZD0837, are both prodrugs that require bioactivation to exert their pharmacological effect. Upon co-administration with erythromycin and ketoconazole, respectively, altered plasma exposure to ximelagatran and AZD0837 and their respective metabolites has been observed. The main objective of this thesis was to characterize the biliary excretion of the compounds, and investigate whether this elimination route explains the observed drug-drug interactions. High plasma-to-bile AUC ratios were observed, in particular for ximelagatran, its active metabolite melagatran, and AR-H067637, the active metabolite of AZD0837. These high ratios indicate the involvement of active transporters in the biliary excretion of the compounds, which is important since transporters constitute possible sites for drug interactions. The effects of erythromycin and ketoconazole on the plasma exposure of the prodrugs and metabolites were confirmed in both the pig and the clinical studies. The changes seen in plasma for ximelagatran and its metabolites were partly explained by reduced biliary clearance. Inhibited CYP3A4 metabolism likely caused the elevated plasma levels of AZD0837, whereas reduced biliary clearance was seen for AR-H067637 suggesting an effect on its excretion into bile. In summary, the studies led to mechanistic insights in the hepatobiliary disposition of ximelagatran and AZD0837, and demonstrate the value of combined clinical and animal studies for the investigation of the biliary drug excretion.
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Reichenwallner, Christopher, and Daniel Wasborg. "Control of a Hydraulic Hybrid System for Wheel Loaders." Thesis, Linköpings universitet, Fluida och mekatroniska system, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-158902.
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In recent years many companies have investigated the use of hybrid technology due to the potential of increasing the driveline’s efficiency and thus reducing fuel consumption. Previous studies show that hydraulic hybrid technology can be favourable to use in construction machinery such as wheel loaders, which often operate in repetitive drive cycles and have high transient power demands. Parallel as well as Series hybrid configurations are both found suitable for wheel loader applications as the hybrid configurations can decrease the dependency on the torque converter. This project has investigated a novel hydraulic hybrid concept which utilizes the wheel loaders auxiliary pump as a supplement to enable both Series and Parallel hybrid operation. Impact of accumulator sizes has also been investigated, for which smaller accumulator sizes resembles a hydrostatic transmission. The hybrid concept has been evaluated by developing a wheel loader simulation model and a control system based on a rule-based energy management strategy. Simulation results indicate improved energy efficiency of up to 18.80 % for the Combined hybrid. Moreover, the accumulator sizes prove to have less impact on the energy efficiency. A hybrid system with decreased accumulator sizes shows improved energy efficiency of up to 16.40 %.
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Meghnous, Ahmed Rédha. "Commande et observation d’une classe de systèmes linéaires à commutations : Application aux convertisseurs de puissance DC-DC." Thesis, Lyon, INSA, 2013. http://www.theses.fr/2013ISAL0137/document.
Full textAbstract:
Cette thèse s’intéresse à la commande et l’observation d’une classe de systèmes linéaires à commutations (SLC). La classe considérée regroupe les systèmes pouvant être représentés par un modèle Hamiltonien à ports. Récemment, plusieurs travaux ont utilisé la théorie des systèmes dynamiques hybrides pour traiter les problèmes de stabilité, de commandabilité et d’observabilité des systèmes linéaires à commutations. Cependant, certains verrous scientifiques demeurent et nécessitent d’être levés tels que la synthèse d’observateurs pour des SLC présentant des modes de fonctionnement inobservables ou la commande hybride de systèmes possédant un nombre réduit d’entrées de commutations et un nombre élevé de variables d’état à contrôler. Dans ce travail, nous nous intéressons à la synthèse d’observateurs s’appuyant sur la modélisation moyenne et la modélisation hybride de SLC ayant une topologie Hamiltonienne à ports particulière. Ce formalisme possède les outils nécessaires pour établir des preuves de stabilité des erreurs d’observation. Dans un premier temps, nous proposons un observateur non linéaire reposant sur le modèle moyen de la classe des SLC considérée. Ensuite, nous traitons le problème de synthèse d’un observateur hybride où nous proposons un observateur commuté prenant en compte les modes de fonctionnement inobservables. Le problème de la commande des SLC est abordé par la suite. Au départ, la théorie de Lyapunov est utilisée pour proposer deux lois de commandes : La première est synthétisée à partir du modèle moyen et la deuxième exploite le modèle hybride. Une commande optimale hybride est élaborée en utilisant le principe du maximum de Pontryagin et une approche utilisant la recherche d’arcs singuliers. Finalement, une commande prédictive hybride est établie à partir d’un modèle discrétisé du système. Des résultats de simulation et une mise en œuvre expérimentale sur un convertisseur DC-DC SEPIC sont donnés pour montrer l’efficacité des méthodes proposées. L’étude d’un tel circuit est motivée par sa topologie particulière qui contient à la fois un mode de fonctionnement observable et un mode de fonctionnement inobservable. En outre, il possède une seule entrée de commutations et quatre variables d’état ce qui lui vaut la réputation être difficile à commanderThis thesis is dedicated to the control and the observation of a class of switched linear systems (SLS). This class contains the systems that can be represented by a port-Hamiltonian model. A lot of works have been studied SLS for several years using an average modeling approach. Recently, various works have shown that hybrid system theory allows to cope with stabilization, controllability, and observability problems of switched linear systems. However, several problems are still open and need more development such as the design of hybrid observers for SLS that have unobservable modes or the control of systems with reduced number of switching inputs and numerous variable states to control. In this work, we are interested in the design of state observers for a particular class of SLS using both the average and the hybrid port-Hamiltonian models. This formalism has the necessary tools to study and establish the stability of the observation errors. At the beginning, a nonlinear observer based on the average modeling is proposed. Next, a hybrid observer is designed for switched linear systems. This observer takes into account the unobservable operating modes of the system. The second point of our work concerns the design of control laws for the considered class of SLS. At first, two Lyapunov-based control laws have been established using either an average model or a hybrid model of the system. A hybrid optimal control based on the maximum principle of Pontryagin and the computation of singular arcs has been also proposed. Finally, a hybrid predictive control based on a discrete model of the system is synthesized. Simulation results and an experimental implementation on a SEPIC converter are given to show the efficiency of the proposed methods. Our motivation to study such a converter is mainly due to its particular topology that includes observable and unobservable subsystems. It is also known to be difficult to be controlled because only one switching input is used to control four state variables
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Voltz, David. "Etude du comportement tribologique des couches composites chimiques Ni-P-SiC en frottement sec /." [S.l.] : [s.n.], 1996. http://library.epfl.ch/theses/?nr=1504.
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Nicholas, Matilda Wray Clarke Stephen H. "A unique memory B cell subset correlates with adverse outomes [sic] in human SLE." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2007. http://dc.lib.unc.edu/u?/etd,1249.
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Thesis (Ph. D.)--University of North Carolina at Chapel Hill, 2007.Title from electronic title page (viewed Mar. 26, 2008). "... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Microbiology and Immunology." Discipline: Microbiology and Immunology; Department/School: Medicine.
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Nguyen, Hai Trung. "Transfert hydrique dans le milieu poreux réactif : Application à l’étude de séchage d’une pâte pure ettringitique au jeune âge." Thesis, Lyon, 2018. http://www.theses.fr/2018LYSEI124/document.
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Les chapes autonivelantes sont souvent composées de ciment alumineux et de sulfate de calcium pour assurer une prise rapide. Le ciment alumineux est généralement à base de monocalcium aluminate (CA). Récemment, un nouveau ciment alumineux riche en mayénite (C12A7) a été conçu pour optimiser l’application des chapes par l’augmentation de la quantité d’ettringite formée. Le développement de l’hydratation au jeune âge (pendant les premières 24 heures) de ce type de produit est pourtant très peu connu. L’objectif principal de cette étude est d’évaluer l’interaction entre l’hydratation au jeune âge et le séchage naturel à travers un modèle de couplage. Ce modèle est appliqué à l’étude d’une pâte pure ettringitique composée de ciment riche en C12A7 et de plâtre alpha. Tout d’abord, un modèle cinétique d’hydratation, initialement développé en système dilué, a été proposé pour étudier l’hydratation d’une pâte pure ettringitique en condition endogène. Il permet de décrire l’évolution en fonction du temps de la porosité, de la teneur en eau, des quantités de phases (réactifs et hydrates). Un modèle de distribution de rayon de pores a été aussi proposé. Ce modèle permet d’obtenir la courbe de pression capillaire au jeune âge nécessaire pour la modélisation des transferts hydriques. Ensuite, une modélisation complète des transferts hydriques a été présentée. Elle a montré que l’hypothèse d’une pression de gaz constante conduit à une surestimation de perte de masse pour des matériaux à faible perméabilité. Pourtant, pour le cas des ciments alumineux, cette hypothèse peut être retenue pour simplifier le couplage avec le modèle cinétique d’hydratation. Enfin, une modélisation des couplages entre l’hydratation et la dessiccation a été développée. L’originalité de ce modèle porte sur l’intégration de la courbe isotherme issue du modèle de distribution poreuse dans la modélisation des transferts hydriques via une fonction Matlab. Le modèle a été capable de reproduire la cinétique de perte de masse d’un échantillon de pâte pure ettringite réactive soumis au séchage précoce. La nécessité de la prise en compte de l’évolution de température a été mise en évidence. De plus, le modèle a prévu un arrêt précoce de l’hydratation à la surface séchante après 10 heures d’hydratation. L’effet de la dessiccation atteint une profondeur de 5 mm sur un échantillon de 3 cm d’épaisseurSelf-leveling flooring compounds (SLC) are often composed of calcium aluminate cements (CAC) and calcium sulfate to ensure rapid setting. The mineral composition of calcium aluminate cements is usually designed around monocalcium aluminate (CA). Recently, a new cement with the main compound of mayenite (C12A7) has been designed to optimize the application of SLC by increasing the amount of ettringite in the hydration product. However, there is a lack of knowledge related to early-age hydration (during the first 24 hours) of this type of product. The main objective of this study is to evaluate the interaction between early-age hydration and natural drying through a coupling model. This model is applied to the study of an ettringite binder composed of cement rich in C12A7 and plaster First, a kinetic model of hydration, initially developed in a diluted system, has been proposed to study the hydration of an ettringite paste under endogenous conditions. It allows to describe the evolution as a function of time of the porosity, the water content, and the quantities of phases (reactants and hydrates). A model of pore size distribution has also been proposed. This model allows us to obtain the capillary pressure curve at early-age, which is necessary for the modeling of moisture transport. Then, a complete modeling of water transfers was presented. It has shown that the assumption of constant gas pressure leads to an overestimation of mass loss for weakly permeable materials. However, for the case of CAC, this hypothesis can be retained to simplify the coupling with the kinetic model of hydration. Finally, a modeling of the coupling between hydration and desiccation has been developed. The originality of this model concerns the integration of the isothermal curve resulting from the pore size distribution model in the modeling of water transfers via a Matlab function. The model was able to reproduce the kinetics of mass loss of a sample of ettringite binder subjected to early drying. The role of temperature was also elucidated. In addition, the model predicted an early stop of hydration on the drying surface after 10 hours of hydration. The effect of desiccation reaches a depth of 5 mm on a sample with a thickness of 3 cm
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Castillón, Fabian Richard. "Rotación de personal y la calidad del servicio logístico en la empresa de tercerización SLI SAC." Master's thesis, Universidad Nacional Mayor de San Marcos, 2019. https://hdl.handle.net/20.500.12672/10408.
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Aborda la alta rotación de empleados en determinadas empresas en relación a la calidad de los servicios, destacándose que el cambio permanente de empleados conlleva a mayores costos de entrenamiento, y afecta el desempeño laboral. El propósito es conocer si existe relación entre “rotación de personal” con “calidad del servicio” existente sobre la compañía proveedora en servicios logísticos “SLISAC”. Las empresas de tercerización en nuestro País, están reguladas mediante la Ley Nº 29245, promulgada en el año 2008, ley que regula la aplicación e implementación de una empresa de tercerización, señalando cuáles son sus facultades y obligaciones, así como las sanciones en caso de desnaturalización de este tipo de actividades. Para la comprobación de las premisas se utilizó el procesamiento estadístico del programa SPSS 24, determinándose la prueba de bondad de ajuste (Chi cuadrada o X 2), aplicado a la hipótesis, cuyo resultado para esta empresa es la no relación de la “rotación del personal” con la “calidad de servicio”. Esta investigación aporta a la gestión de las empresas de tercerización, la importancia que tiene la rotación del personal y las condiciones de trabajo en la calidad de servicios.Tesis
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Ahlin, Gustav. "In vitro and in silico prediction of drug-drug interactions with transport proteins." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-107492.
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Arquier, Bernard. "Le double sarcophage de Mésehti S1C (CG 28118) - S2C (CG 28119) : recherches sur l'organisation du décor iconographique et textuel." Phd thesis, Université Paul Valéry - Montpellier III, 2013. http://tel.archives-ouvertes.fr/tel-00937051.
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Le double sarcophage de Mésehti, nomarque d'Assiout et grand prêtre d'Anubis et d'Oupouaout, est conservé au Musée du Caire. Sur l'extérieur des couvercles et des parois sont inscrits des textes religieux et funéraires peu habituels et pour partie dérivés des Textes des Pyramides (Livre de Nout). Seul le sarcophage intérieur porte un décor figuré à l'intérieur. Le couvercle du sarcophage intérieur est décoré d'une horloge stellaire diagonale (HSD) associée à deux registres de TS. Mais ces deux sarcophages servent surtout de support à une grande quantité de Textes des Sarcophages. Dans ce corpus, on constate la répétition d'un grand nombre de chapitres, sur une même paroi par le phénomène d'emboîtement et sur des parois différentes par l'association en séries ou séquences. Le choix des textes et de leur enchaînement répond à un souci d'établir un discours relatif au devenir au défunt dans l'au-delà. L'organisation spatiale par le choix des parois et la répétition de certains TS y est subtile et performative. La répétition des TS met en évidence une adaptation des textes à la paroi support et au contexte du discours. À cette mise en espace, à cet aspect discursif, est associée une insertion dans le temps par la présence de l'HSD et par l'établissement d'un cycle de lecture des parois des deux sarcophages. Cette étude de l'organisation du décor et des textes est complétée par une analyse de certains thèmes choisis.
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Russell, Laura M. "Thermal conductivity/diffusivity of SiC-Mullite and SiC-SiC composites." Thesis, Virginia Tech, 1987. http://hdl.handle.net/10919/40981.
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The purposes of this study were to determine as a function of temperature the thermal diffusivity and/or thermal conductivity of SiC-Mullite and SiC-SiC, and to explain the observed behavior in terms of changes in temperature, microstructure, composition, and/or orientation.
Materials used in the SiC-Mullite study consisted of single crystal SiC whiskers (prepared from rice hulls or by the vapor-liquid-solid process) dispersed within a polycrystalline mullite matrix. During measurement of thermal diffusivity, the samples were heated to l500°C and cooled back to room temperature. No hysteresis occurred. However, both thermal diffusivity and conductivity exhibited maximum values at room temperatures, perpendicular to the hot pressing direction, at high volume percentages of SiC whiskers, and when VLS whiskers were employed.
The SiC-SiC samples consisted of a crossweave of polycrystalline SiC uÌ bers that were coated with phenolic resin and surrounded by a chemically-vapordeposited matrix of SiC. The two types of samples examined were prepared with different amounts of resin. The matrices of the high resin samples were found to be dominated by the presence of char. Samples were cycled to 1000, 1400, and l800°C; hysteresis occurred on some of the cycles. Thermal diffusivity was highest parallel to one set of fibers.
These results allow the qualitative tailoring of the heat flow properties of these ceramic composites, for particular applications, and set forth limitations on the use of the SiC-SiC composites at high temperatures.
Master of Science
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Skala, Jakub. "Modelování podnikových procesů." Master's thesis, Vysoká škola ekonomická v Praze, 2008. http://www.nusl.cz/ntk/nusl-12361.
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The diploma thesis deals with the theme of Modeling business processes with orientation to the metric process interface. The aim of the thesis is to design the architecture of metric, which enabled to construct type metrics of the process interface. Firstly, the reader is informed about the basic terms related to process modeling, process management and connection of strategy with metrics. The next part describes the architecture of metrics created, which is oriented to supporting the process management of the organization. The set of type metrics was chosen with consideration to the possibility of their placement on process interface. The set created in this manner should help to connect strategy with processes when implementing into organization. The last part of the thesis describes the practical application of knowledge obtained in the PARMA project. This project deals with the proposal and implementation of the process management into the Bureau of the Municipality of Prague 10. The thesis deals with two processes and the conclusions obtained in the theoretic part of the thesis are applied herein.
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Bertrand, Sébastien. "Amélioration de la durée de vie de composites SiC/Sic à interphases nanoséquencées (PyC/SiC)n et (BN/SiC)n." Bordeaux 1, 1998. http://www.theses.fr/1998BOR10607.
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Des minicomposites et des composites 2d tisses sic/sic avec des interphases multicouches nanosequencees pyrocarbone / carbure de silicium (pyc/sic)#n ou nitrure de bore / carbure de silicium (bn/sic)#n ont ete elabores par infiltration chimique en phase vapeur pulsee (p-cvi). Ces materiaux presentent une resistance a l'oxydation, sous charge en temperature, bien superieure a celle que confere une interphase monocouche de pyc ou de bn ; tout en ayant des caracteristiques mecaniques a l'ambiante comparables. Des traitements specifiques de la fibre hi-nicalon ont egalement permis d'augmenter (i) la thermostabilite de la fibre, (ii) sa resistance a la fissuration sous-critique, (iii) l'intensite de la liaison fibre / matrice des composites et (iv) la resistance a l'oxydation, sous charge, des fibres et des composites.
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Bergerat, Jean-Michel. "Etude du comportement à la rupture de composites ALO/ALO.AlO/SiC et SiC/SiC." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb376118559.
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SUH, Min-Soo. "Wear Mechanisms on SiC and SiC/SiC Composites under Sliding Friction and Erosive Wear." Kyoto University, 2010. http://hdl.handle.net/2433/126768.
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Woods, Christopher Huia. "Masqueulinities [sic] an [sic] MA thesis by practice /." Click here to access this resource online, 2007. http://repositoryaut.lconz.ac.nz/theses/1368/.
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Vine, Wendy Jane. "Electron microscopy of SiC and SiC related composites." Thesis, University of Bristol, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333867.
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Carrere, Philippe. "Comportement thermomécanique d'un composite de type SiC/SiC." Bordeaux 1, 1996. http://www.theses.fr/1996BOR10703.
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Dans les composites sic/pyc/sic, initialement developpes pour des applications structurales a hautes temperatures, l'interface de pyrocarbone est sensible a l'oxydation. L'addition de bore dans la matrice favorise la formation d'un verre qui permet la cicatrisation des fissures. Le comportement thermomecanique de ce materiau sic/sibc a donc ete etudie a des temperatures comprises entre 700c et 1200c, sous atmosphere inerte ou oxydante en traction uniaxiale, en fatigue statique ou cyclique. Ce travail a permis de determiner la contribution des contraintes residuelles sur la fissuration matricielle, l'influence de l'etat d'endommagement initial de la matrice sur la vitesse de fluage et enfin les mecanismes de comportement et de rupture a chaud sous air qui dependent de la vitesse de mise en place de la protection vitreuse et de son etancheite
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ABBE, FRANCOIS. "Fluage en flexion d'un composite sic-sic 2d." Caen, 1990. http://www.theses.fr/1990CAEN2029.
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Un composite bidirectionnel a matrice de carbure de silicium renforcee par des fibres longues de carbure de silicium a fait l'objet d'une etude de comportement et resistance en fluage dans le domaine de temperature 1273 k-1773 k par des essais en flexion 3 points sous vide. Un marquage lithographique de la surface d'eprouvette, supportant des hautes temperatures, a permis de developper une methodologie de deconvolution de l'essai de flexion donnant acces aux lois de comportement en traction et en compression dans le domaine stationnaire. Une modelisation du stade transitoire a ete effectuee conduisant a la validation de l'approche menee. La description de l'evolution de l'endommagement au cours du fluage semble pouvoir etre decrite par les concepts de la mecanique des milieux continus endommages. Le lien avec l'approche precedente consiste a introduire la valeur non nulle de la zone endommagee au stade stationnaire obtenue lors de l'utilisation de la methode de deconvolution. Le seuil de contrainte, a partir duquel cette zone endommagee apparait, est directement correle aux mesures par micro-indentation du cisaillement interfacial fibre/matrice que nous avons effectuees. Les valeurs des parametres morphologiques fondamentaux necessaires aux differentes approches ont ete obtenues a l'aide des techniques d'analyse d'images. La microscopie electronique a trans-mission nous a apporte les complements d'informations dont nous avions besoin pour justifier l'interpretation du comportement mecanique observe experimentalement. Le role fondamental de l'interface et des proprietes thermomecaniques de la fibre dans un environnement particulier (vide) ont ete clairement mis en evidence
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Doubrava, Jan. "Vyhodnocování SLA nad HP Quality Center." Master's thesis, Vysoká škola ekonomická v Praze, 2012. http://www.nusl.cz/ntk/nusl-165251.
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The objective of this thesis is to propose and describe the database, which enables to measure compliance of Service Level Agreement suppliers of software applications that work with HP Quality Center. The work describes specific solution used in project to implement a new core business system, describes requirements for functionality and use of result the solution. Briefly described is also HP Quality Center, the testing tool, from which are taken the input data and what possibility offers for monitoring the SLA. The proposed database allows calculation of the time which is actually spent by suppliers on solving the errors and comparison of calculated time with the defined SLA. It will also describe how to import data into the database and the basic reports, which are usable after implementation of the proposed solution.
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Harper, J. M. "Smooth SLE." Thesis, University of Cambridge, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.603730.
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The search for the scaling limits of two-dimensional critical systems has been a very active area of research in Statistical Physics. Recently, a new technique for the analysis of these scaling limits was developed after the introduction of a process known as the Stochastic Loewner Evolution (SLE) by Oded Schramm. This process is a stochastic version of the Loewner chain from classical complex analysis, in which the driving function of the chain is taken to be a Brownian motion. The behaviour of SLE has been widely studied and has enabled the rigorous identification of the scaling limits of several discrete critical systems including critical site percolation on the triangular lattice. Many other systems are also conjectured to converge to some SLE-related process. The study of the behaviour of SLE has also lead to the exact calculation of many quantities relating to the asymptotic behaviour of these discrete models. In this study, we review the theory of classical Loewner chains before introducing a process that can be viewed as a smooth analogue of a Loewner chain. We study the properties of this process and show that it possesses a greater degree of regularity than a classical Loewner chain; in particular, we show that the planar domains associated with the smooth chain have smooth boundaries. We then study these smooth chains in the stochastic setting of Schramm, calling the resulting process a smooth SLE. One main difference between SLE and smooth SLE is that SLE possesses a certain scale-invariance, whereas smooth SLE processes do not. This scale-invariance is often crucial to the proofs of the behaviour of SLE and therefore any proof of corresponding behaviour for the smooth case must use other methods. The extra regularity of the smooth chain implies that some of the behavioural exhibited by an SLE process is not seen for a smooth chain. However, the main behavioural phase change, seen for SLE when the variance parameter of the driving Brownian motion is changed, is also seen in the smooth case. Finally, we examine issues relating to the approximation of smooth Loewner chains and also the convergence of these smooth chains to their classical counterparts.