Teses / dissertações: "E.B. Moore and Co"

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Ivanauskaitė, Ilma. "Mokslinio žurnalo tinklalapio kūrimas". Master's thesis, Lithuanian Academic Libraries Network (LABT), 2009. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2009~D_20090618_182844-59741.

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Baigiamajame magistro darbe nagrinėjamas mokslinio žurnalo tinklalapio kūrimas. Atliktas kuriamo tinklalapio palyginimas su kitų universitetų ar institutų mokslinių žurnalų tinklalapiais. Taip pat atliktas palyginimas ir su užsienio mokslinių žurnalų tinklalapiais. Darbe apžvelgiami MySQL duomenų bazėse naudojami paieškos algoritmai. Aptariamas B medžio paieškos algoritmas, elemento įterpimas bei šalinimas iš B medžio. Taip pat aptariamas Turbo Boyer-Moore paieškos algoritmas. Pateikiami tinklalapyje atlikti patobulinimai, tokie kaip puslapis keliomis kalbomis, paieškos langas, straipsnių pateikimo dizainas ir kt. Atlikus tinklalapių palyginimą bei tinklalapio patobulinimą, pateikiamos baigiamojo darbo išvados bei pasiūlymai, tokie kaip paieška pagal reikšminius žodžius iš reikšmių sąrašo, paieškos žodžio pasiūlymas, CSS failų bei turinio valdymo sistemos panaudojimas. Apžvelgiamos PHP programavimo kalbos funkcijos skirtos rašybos klaidų taisymams.
The thesis analyse website development of scientific journal. The developed website comparison with others universities and institutes scientific journal websites was made. There was also made a comparison with foreign scientific journal websites. Thesis reviews search algorithms that are used in MySQL databases. The B tree search algorithm, insertion and elimination of element in it are described. There is also presented Turbo Boyer – Moore search algorithm. The thesis presents improvements of website, such as pages in several languages, search page, design of articles presentation and others. Conclusions and proposals, such as search by key words from the list, search word proposal, usage of CSS files and content management system are made after comparisons and improvements of website. PHP functions for spelling mistakes are described.

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Bollero, Real Alberto. "Isotropic nanocrystalline (Nd,Pr)(Fe,Co)B permanent magnets". Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2003. http://nbn-resolving.de/urn:nbn:de:swb:14-1069758225796-19366.

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Nanokristalline Permanentmagnete zeigen ungewöhnliche magnetische Eigenschaften aufgrund von Oberflächen- und Grenzflächeneffekten, die verschieden von denen massiver oder mikrokristalliner Materialien sind. Diese Arbeit zeigt Ergebnisse einer systematischen Untersuchung der Beziehung zwischen Mikrostruktur und magnetischen Eigenschaften von isotropen nanokristallinen (Nd,Pr)(Fe,Co)B-Permanentmagneten. Hochkoerzitive Magnete vom Typ (Nd,Pr)FeB wurden durch hochenergetisches Mahlen in der Kugelmühle oder Rascherstarrung hergestellt. Der Einfluss geringer Mengen von Zusätzen wie Dy und Zr und die Substitution von Nd durch Pr auf die magnetischen Eigenschaften wird dargestellt. Weiterhin wurde eine Einschätzung des Warmumformverhaltens dieser Materialien durchgeführt. Hochenergetisches Kugelmahlen einer Legierung mit der Anfangszusammensetzung Pr9Nd3Dy1Fe72Co8B6.9Zr0.1 führte, nach Glühbehandlung, zu fast einphasigem Magnetpulver mit einem maximalen Energieprodukt von (BH)max~140 kJm-3. Das hochenergetische Kugelmahlen wurde zu einer sehr vielseitigen Technik zur Herstellung hochleistungsfähiger Nanokompositmagnete weiterentwickelt. Das Zulegieren unterschiedlicher Anteile von weichmagnetischem alpha-Fe ist damit sehr effektiv möglich. Der Zusatz von 25 Gew.-% alpha-Fe führt zu einem hohen (BH)max=178kJm-3. Dies wird auf eine sehr effektive Austauschkopplung zwischen den hart- und weichmagnetischen Phasen zurückgeführt. Die Natur der intergranularen Wechselwirkungen kann durch die Wohlfarth´sche Remanenzanalyse (?deltaJ-plot¡§) beschrieben werden. Im speziellen wurden deltaJ-Diagramme für verschiedene (i) alpha-Fe Gehalte, (ii) Korngrößen und (iii) Austauschlängen erstellt. Es konnte gezeigt werden, dass in den Nanokompositmagneten auf Pr-Basis keine Spinumorientierung auftritt. Abschließend zeigt die Arbeit die Möglichkeit der Nutzung einer mechanisch aktivierten Gas-Festkörper-Reaktion auf, mit der eine sehr feinkörnige Mikrostruktur erhalten wird. Die Untersuchungen wurden mit stöchiometrischen Nd2(Fe1-xCox)14B-Legierungen begonnen (x=0-1). Die Verbindungen wurden unter höheren Wasserstoffdrücken und Temperaturen gemahlen, wodurch sie zu NdH2+delta und krz-(Fe,Co) (x=0-0.75) oder kfz-Co (x=1) entmischt wurden. Die Korngrößen des rekombinierten Nd2(Co,Fe)14B-Materials liegen im Bereich von 40-50 nm
Nanocrystalline permanent magnets present unusual magnetic properties because of surface/interface effects different from those of bulk or microcrystalline materials. This work presents results of a systematic investigation of the relationship between microstructure and magnetic properties in isotropic nanocrystalline (Nd,Pr)(Fe,Co)B permanent magnets. Highly coercive (Nd,Pr)FeB-type magnets have been produced using high energy ball milling and melt-spinning. The influence of small amounts of additives, Dy and Zr, and the substitution of Nd by Pr on the microstructural and magnetic properties are shown. An assessment of the hot deformation behaviour has been carried out. Intensive milling of an alloy with starting composition Pr9Nd3Dy1Fe72Co8B6.9Zr0.1 yields, after annealing treatment, nearly single-phase magnet powders with a maximum energy product (BH)max?î140kJm-3. Co has a beneficial effect on the intrinsic magnetic properties but also on the microstructure, with a mean grain size of 20nm. Intensive milling is used to produce high-performance nanocomposite magnets by blending this latter alloy with different fractions of soft magnetic alfa-Fe. Addition of 25wt.% alfa-Fe leads to a high (BH)max=178 kJm-3 due to an effective exchange-coupling between the hard and the soft magnetic phases. The intergrain interactions between the crystallites of the nanocomposite structure are analysed. Demagnetisation recoil loops of the nanocomposite magnets show relatively open minor loops due to the exchange-spring mechanism. Information about the intergrain interactions during demagnetisation are obtained by plotting the deviation of the demagnetising remanence from the Wohlfarth-model (¡§deltaJ-plot¡¨). Exchange-coupling phenomena are studied by analysing the evolution of the corresponding deltaJ values when varying (i) the alfa-Fe content, (ii) the annealing temperature, i.e. the grain size and (iii) the measurement temperature. Low temperature measurements do not reveal any sign of spin reorientation for these Pr-based nanocomposite magnets. The work concludes showing the possibility of using a mechanically activated gas-solid reaction to obtain an effective grain refined microstructure starting from stoichiometric Nd2(Fe1-xCox)14B alloys (x=0-1). These compounds were milled under enhanced hydrogen pressure and temperature leading to their disproportionation into NdH2+delta and bcc-(Fe,Co) (x=0-0.75) or fcc-Co (x=1). Grain sizes of recombined Nd2(Fe,Co)14B materials were found to be 40-50nm

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Matthews, Gail Veronica National Centre in HIV Epidemiology &amp Clinical Research Faculty of Medicine UNSW. "Therapeutic strategies in HIV and Hepatitis B co-infection". Awarded by:University of New South Wales. National Centre in HIV Epidemiology & Clinical Research, 2009. http://handle.unsw.edu.au/1959.4/44538.

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Individuals with HIV-HBV coinfection are at risk of accelerated hepatic fibrosis, and end stage liver disease is now a major cause of morbidity and mortality in this population. For many years lamivudine (3TC) monotherapy was the only effective treatment for HBV in coinfected individuals, but its use was complicated by the frequent development of HBV drug resistance, and loss of virological suppression. With the availability of new potent antivirals for HBV, including tenofovir (TDF), therapeutic options for HIV-HBV coinfected individuals have increased, although the management of HBV disease in this population is still often suboptimal. This thesis explores through a series of published papers, issues in the current management of HIV-HBV coinfected individuals_ Chapter 1 describes a high incidence of 3TC resistance in HIV-HBV individuals on extended 3TC monotherapy, and in particular, a significant proportion with complex HBV-drug resistant mutants, with potential public health implications. In Chapter 2 the benefits of TDF ???induced virological suppression on parameters of end stage liver disease are described. Chapters 3 and 6 explore the role of TDF as monotherapy, or in combination with 3TC, within HBV-active antiretroviral therapy (ARn. No benefit for TDFj3TC combination versus TDF monotherapy is observed in treatment naive individuals; although a potential benefit for combination therapy is observed in treatment experienced subjects. In Chapter 4 a high rate of hepatic flare (HF) after initiation of HBV-active ART is described, and potential predictors of flare including elevated baseline ALT and HBV DNA are identified to suggest HBV immune restoration disease (IRD) as the major underlying cause of HF in this study. Chapter 5 discusses the immunopathogenesis of HBV IRD in more detail and proposes guidelines for clinical management. In summary the thesis finds that the therapeutic outlook for HIV-HBV coinfected individuals is generally optimistic, although several further research areas are identified, particularly in middle and low- income settings where the burden of HIV and HBV disease is greatest.

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Wang, Xiao Qian. "The Impact of Hepatitis B co-infection on the HIV Reservoir". Thesis, University of Sydney, 2020. https://hdl.handle.net/2123/22895.

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Hepatitis B virus (HBV) co-infection increases overall and liver-related mortality in people living with HIV, yet the relationship between these two viruses is still poorly understood. We determined whether levels of HIV were associated with markers of HBV infection, immune activation and inflammation or liver damage. We also designed an assay to sequence full-length HIV RNA in order to further validate our findings. HIV-HBV co-infected and HIV mono-infected participants, naïve to ART, were recruited in Bangkok, Thailand as part of a prospective observational cohort study. HIV proviruses were sequenced from peripheral blood (PB) CD4+ T cells using full-length individual proviral sequencing. Spearmans rank correlations tests were performed to determine associations. RNA extraction and cDNA synthesis protocols based on previously established Single Copy Assay and Single Genome Sequencing methods were optimised to yield a full-length HIV fragment. The 1337 and 285 HIV proviruses were sequenced from 19 HIV-HBV co-infected and 6 HIV mono-infected individuals respectively, although 2 co-infected and 1 mono-infected individual was excluded due to infection with non-subtype AE HIV virus. More genetically intact proviruses (22-1000 copies/106 cells, p=0.02) was observed in the co-infected individuals compared to the mono-infected. For the HIV-HBV cohort, the levels of soluble CD14, LPS and AST in the blood were significantly correlated with the frequency and the genetic diversity of intact HIV proviruses (p<0.05). However, markers of HBV disease (HBV DNA, HBsAg, HBeAg status) and markers of inflammation in both the blood and liver (CXCL10, CCL2, and CXCR3) were not found to be significantly associated with levels of intact HIV (p>0.05). We were also able to present a preliminary HIV RNA sequencing assay to sequence ~90% of the HIV RNA genome with a single amplicon. During HIV-HBV co-infection, the frequency and genetic diversity of the intact proviruses within PB CD4+ T cells from the HIV-HBV co-infected individuals appears to be independent of levels of markers of HBV or liver damage, but may be associated with markers of immune activation.

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Fajnorová, Markéta. "Návrh marketingové strategie firmy Inspur Group Co. ltd. pro český trh". Master's thesis, Vysoká škola ekonomická v Praze, 2011. http://www.nusl.cz/ntk/nusl-82017.

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The diploma thesis is structured into three chapters, while the first chapter informs about theoretical concept of B-2-B marketing, defines basic specifics of B-2-B market and concerns about actual trends and frequent mistakes, which are made while preparing B-2-B marketing strategy. Next chapter informs about actual situation on the server market in the Czech Republic and mainly focuses on the external and internal environment of the firm. The last chapter is based on the personal discussion with potential distribution and service partners that provided useful information about the concurrence, actual situation on the market and defined trade requirements towards Inspur.

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Del, Nagro Christopher J. "B cell co-receptors CD19 and CD21 in tolerance and auto-immunity". Diss., Connected to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2005. http://wwwlib.umi.com/cr/ucsd/fullcit?p3190009.

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Thesis (Ph. D.)--University of California, San Diego, 2005.
Title from first page of PDF file (viewed March 14, 2006). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references.

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7

Prince, Darren William. "The Co-Transcriptional Response of Intracellular Group B Streptococcus (GBS) and Monocytes". Thesis, Griffith University, 2019. http://hdl.handle.net/10072/389087.

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Group B Streptococcus (GBS) is a species of gram positive bacteria representing a significant human pathogen; namely, as the most prolific cause of neonatal disease and mortality globally, but also increasingly reported in adult disease (especially among the elderly and those with compromised immune systems). The first chapter of this thesis reviews the extensive literature covering GBS; with a focus on classification and disease. Selected virulence factors are also discussed. In chapter 2, eight strains of GBS were selected for whole genome sequencing by Third Generation, Pacific Biosystems (PacBio) sequencing technology. A protocol was optimised to provide sufficient, high quality genomic preparations from multiple strains of GBS – suitable for the PacBio technology. Using a sequenced strain of GBS from chapter 2, an infection model was optimised in chapter 3 for the purpose of providing quality RNA for co-transcript analysis. U937 human monocytes were infected with GBS (strain 874391) and the host/pathogen RNA prepared from the same reaction (monocytes with internalised GBS) – with an emphasis on yielding sufficient pathogen RNA; which can sometime be an impediment for co-transcript studies. Pathogen RNA derived from the optimised infection protocol was demonstrated to amplify with RT-qPCR for 12 tested GBS genes (cylE, 1010, rib, czcD, pil2B, cpsE, scpB, htp, cfb, copA, hvgA and maeA). In chapter 4, RT-qPCR was used to analyse differential gene expression from the mixed, host/pathogen RNA. Twelve human genes and 12 GBS genes were assessed for differential gene expression. Seven of the tested human genes (IL8, IL1A, IL1B, IL10, TNF, LMO2 and MCP-1) and 6 of the tested GBS genes (scpB, 1010, rib, czcD, htp, hvgA) were significantly upregulated in RNA derived from the infection samples. Of the GBS genes tested, htp was the most upregulated. An htp knockout mutant of GBS strain 874391 (Δhtp) was constructed for chapter 5 of this thesis to assess the impact of htp transcription on GBS survival in an infection context. The infection assays optimised in chapter 3 were performed with the Δhtp GBS construct. Contrary to expectation, the Δhtp GBS construct survived the internalised environment of the monocytes in significantly higher numbers than the wild-type over 48 hours of infection.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Medical Science
Griffith Health
Full Text

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Rivier, Elodie. "La co-création de service B to B : Une étude des déterminants de l’engagement des entreprises dans un processus d’innovation des services". Thesis, Orléans, 2014. http://www.theses.fr/2014ORLE0502.

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Au vu du contexte actuel (mondialisation des échanges, concurrence, innovations technologiques…), les entreprises doivent trouver les moyens de proposer des produits et services toujours plus innovants pour se différencier. C’est pourquoi, elles font de plus en plus appel aux compétences des clients pour concevoir leurs offres qui correspondront davantage à leurs besoins. Cette pratique qui suscite un réel engouement auprès des managers est appelée « co-création ».Or, d’après la littérature, il semblerait que peu de recherches ne se sont intéressées aux raisons pour lesquelles certaines entreprises sont plus prédisposées que d’autres à co-créer des services dans le contexte interorganisationnel (Business-to Business, B to B). Pourtant, cette question est fondamentale. En effet, s’il est démontré que certains facteurs favorisent l’adhésion des clients et la gestion de projets de co-création, les organisations pourront mieux choisir des partenaires (candidats) à un projet de co-création. Ainsi, notre travail de recherche propose de répondre à la question suivante : Pourquoi certaines entreprises sont-elles plus disposées à co-créer un service alors que d’autres le sont moins ?Dès lors, après avoir réalisé un état de l’art sur la co-création de services, nous menons deux études qualitatives auprès de dirigeants et de clients B to B impliqués dans des démarches de co-création de services innovants. La troisième étude de nature quantitative est réalisée auprès d’un échantillon de prestataires de services destinés aux entreprises afin de tester nos hypothèses de recherche. Les résultats obtenus ont permis d’identifier des critères à la fois organisationnels (spécifiques à l’entreprise) et sectoriels (c’est-à-dire, relatifs au marché) explicatifs de la prédisposition et du degré d’implication des entreprises dans un processus de co-création. D’un point de vu managérial, cette recherche souligne les bonnes pratiques à mettre en place au sein des organisations avant d’initier cette démarche collaborative
In the current world context (globalization, competition, technological innovations,.), companies must look for new ways to offer more innovative goods and services. Therefore, they require customer’s competencies to design offerings that meet their needs. This practice which is raising a great deal of enthusiasm from the managers is called “co-creation”.An examination of the existing literature on services suggests that little has been done on the reasons why some companies are more disposed to engage in a B to B service co-creation process while others are less disposed to do so. Yet, this is an important issue. Indeed, if we can show that there are some criteria which can be used to identify potential co-creators and that facilitate the management of co-creation projects, then organizations could use this knowledge to select their partners in a co-creation process.In the light of the foregoing, our research study seeks to answer the following question: Why are some B-to-B service providers more disposed to co-create services than others?After a literature review on service co-creation, we conduct two qualitative studies with leaders and B to B customers involved in innovative service co-creation projects. The third study that is quantitative surveys a number of service providers in order to test our research hypothesis.Our empirical results allow us to identify firm-level and industry-level criteria relevant for explaining businesses’ willingness to engage in a co-creation process as well as their level of involvement in this process. From a managerial perspective, the present research also underlines the best practices to implement in service organizations before starting such a collaborative approach

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Márquez, Lobato Yolanda. "Study of the monofilar suture based on the segmented copolymer GL-b-(GL-co-TMC-co-CL-)-b-GL thermal behavior, degradability and incorporation of active agents : polymers and biopolymers". Doctoral thesis, Universitat Politècnica de Catalunya, 2016. http://hdl.handle.net/10803/404331.

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Biomaterials based on block segmented copolymers constituted by hard and soft segments have attracted much attention for biomedical applications in the last decades, specifically as absorbable monofilament sutures. Polyglycolide has demonstrated to be a good candidate to constitute the hard segment due to its biodegradability and high stiffness, whereas the incorporation of different monomers (e.g. -caprolactone, trimethylene carbonate or glycolide) in a random distribution as soft segment promotes material flexibility and enhances in vitro degradation rates. Resulting material properties can be tailored by the combination of different ratios of hard and soft segments and the specific monomer composition. In this Thesis the study of a tricomponent segmented copolymer commercially marketed as Monosyn® by B. Braun Surgical as an absorbable monofilament suture is presented. The main goals of the work concern to: a) the complete physical characterization that involves the study of the crystallization kinetics and thermal stability, b) the study of the degradation behavior and the associated microstructural changes, c) the evaluation of the capability to improve the performance of Monosyn® by adding compounds with pharmacological activity and d) the production of nanofibers to be employed as reinforcing agents. Isothermal and non-isothermal crystallizations were followed by different techniques (e.g. optical microscopy, differential scanning calorimetry and time-resolved SAXS experiments in a synchrotron radiation facility). The composition of the soft segment influenced in the crystallization of the segmented copolymer as could be deduced by comparison with reported data on similar bicomponent systems. Hydrolytic degradation was carried out at different temperatures and in buffered media of a continuous range of pH. Surface morphology of hydrolyzed sutures showed the formation of longitudinal and circumferential cracks in the outer and inner part of the suture, respectively. These fractures were associated to the existence of interfibrillar and interlamellar amorphous domains as was revealed by SAXS experiments. To explore the potential applications of Monosyn® as an absorbable monofilament suture with pharmacological activity, different drugs were incorporated. Moreover, the use of an amorphous copolymer coating was also evaluated. The first group of drugs selected were biguanide compounds (i.e. chlorhexidine and polyhexametilen biguanide), which have a well-recognized bactericide activity. Specifically, the effectiveness of using a coating was proved as well as the influence of drug molecular size in the activity. The study of the loading process, release behavior and pharmacological activity was completed considering an antibiotic (chloramphenicol) and a healing agent (captopril). Finally, nanofibers of the selected copolymer were prepared by means of the electrospinning technique. These nanofibers were also loaded with pharmacological drugs and used as reinforcing agent of biodegradable polymer matrices. In order to obtain appropriate fabrics different fiber compositions and electrospun set up configurations were tested.
En las últimas décadas, los biomateriales basados en copolímeros segmentados, constituidos por segmentos duros y blandos, han atraído el un creciente interés para una amplia gama de s aplicaciones biomédicas, especialmente como suturas monofilares absorbibles. Se ha demostrado que la poliglicolida es una buena candidata para constituir el segmento duro debido a su biodegradabilidad y a su alta rigidez, mientras que la incorporación de distintos monómeros (por ejemplo, -caprolactona, carbonato de trimetileno o glicolida) en una disposición estadística como segmento blando promueven la flexibilidad del material y mejoran la velocidad de degradación in vitro. Las propiedades de los materiales resultantes pueden ajustarse combinando diferentes proporciones de los segmentos duro y blando, y con una composición específica de monómero. En esta Tesis se presenta el estudio del copolímero segmentado tricomponente comercializado por B.Braun Surgical como sutura absorbible monofilar con el nombre de Monosyn®. Los principales objetivos de este trabajo son: a) la caracterización física completa que incluye el estudio de estabilidad térmica y cinéticas de cristalización, b) el estudio de la degradación y los cambios microestructurales asociados, c) la evaluación de la mejora del uso de la sutura añadiendo componentes con actividad farmacológica, y d) la producción de nanofibras para utilizarlas como agentes reforzantes. Las cristalizaciones isotérmicas y no isotérmicas se siguieron mediante distintas técnicas (microscopía óptica, calorimetría diferencial de barrido y experimentos de difracción de rayos X de bajo ángulo). La composición del segmento blando influyó en la cristalización del copolímero segmentado, como era de esperar por la comparación con los datos publicados del sistema bicomponente similar. La degradación hidrolítica fue llevada a cabo a distintas temperaturas con disoluciones tamponadas en un rango continuo de pH. La morfología de la superficie de las suturas hidrolizadas mostró la formación de fracturas longitudinales y circunferenciales en la zona externa e interna de la sutura, respectivamente. Estas fracturas se asociaron a la existencia de dominios amorfos interfibrilares e interlamelares, tal y como se corroboró mediante los experimentos de difracción de rayos X de bajo ángulo. Para explorar las aplicaciones potenciales de Monosyn® como sutura absorbible monofilar con actividad farmacológica, se incorporaron distintos fármacos. Además, se evaluó el uso de un copolímero amorfo como recubrimiento. El primer grupo de fármacos seleccionados corresponden a la familia de las biguanidas (clorhexidina y polihexametilen biguanida), conocidas por su actividad bactericida. En particular se probó la efectividad de utilizar un recubrimiento y la influencia del tamaño molecular del fármaco en su actividad. El estudio del proceso de carga, el perfil de liberación y la actividad farmacológica se completó considerando también un antibiótico (cloranfenicol) y un agente cicatrizante (captopril). Por último, se prepararon nanofibras del copolímero seleccionado mediante la técnica del electrohilado. Estas nanofibras se cargaron con fármaco y se utilizaron como agentes reforzantes de matrices poliméricas biodegradables. Con el propósito de conseguir unos tejidos apropiados, se probaron distintas composiciones de fibras y diferentes configuraciones en el montaje del sistema de electrohilado.

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Mayot, Hervé. "Contribution à l'étude cristallographique et magnétique de composés intermétalliques R–Co–B et R–Fe–B (R ≡ élément de terres rares)". Phd thesis, Grenoble 1, 2008. http://www.theses.fr/2008GRE10229.

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Nous nous sommes attaché à étudier les liens entre propriétés cristallographiques et magnétiques de phases intermétalliques R M-B où R est un élément de terres rares, l'yttrium ou le thorium et M un métal de transition 3d. La présence de bore dans l'environnement atomique des sites de métaux de transition, notamment, agit fortement sur les propriétés magnétiques tant à l'échelle macroscopique que microscopique. Nous apportons une contribution à l'étude des propriétés magnétiques particulières du composé YCo4B, composé modèle et de référence de la famille Rn+mCo3n+5mB2n. L'anisotropie magnétocristalline originale de ce composé est caractérisée à la fois par une réorientation de spin et un processus d'aimantation du premier ordre. Elle s'avère également fort sensible à la pression comme l'ont montré nos mesures magnétiques. La substitution du fer au cobalt dans les composés RCo4B est possible et donne lieu à un schéma préférentiel comme l'illustre nos mesures de diffraction des neutrons. En combinant ces résultats à des mesures magnétiques diverses et de spectroscopie Mössbauer, les propriétés magnétiques de chaque site cristallographique de métaux de transition 3d ont pu être particularisées. Nous avons étudié la solution solide Y1-xThxCo4B et montré l'existence d'une substitution préférentielle du thorium à l'yttrium sur un site cristallographique. Ces deux éléments R non magnétiques ont des effets différents sur les propriétés magnétique des composés. Par comparaison à des études magnétiques sous pression, il a été possible de montrer que ces différences sont principalement dues aux différences de configuration électronique entre le thorium et l'yttrium et peu aux évolutions structurales induites par la substitution. De nouveaux composés de la famille structurale Rn+mCo3n+5mB2n ont été mis à jour récemment. Nous présentons des études des conditions de synthèses et des structures magnétiques de quelques phases R3Co13B2 et R5Co19B6. Le composé Pr5Co19B6 présente notamment des anomalies magnétiques interprétables comme une réorientation de spin à basse température. Nous présentons des résultats d'absorption des rayons X réalisés sur plusieurs compositions de la solution solide CeCo12-xFexB6. Dans cette structure, le cérium présente un état de valence intermédiaire qui évolue notablement en fonction de la teneur en fer. Enfin, nous avons précisé les conditions de synthèse de phases métastables Nd2Fe23B3 et Y3Fe62B14, très riches en fer. Ces structures originales présentent de nombreux types d'environnements atomiques du fer ce qui en fait des composés aux propriétés magnétiques intéressantes. Nous avons notamment montré les évolutions inhabituelles de ces propriétés magnétiques entre les états amorphe et cristallisé de ces alliages
We studied the relationship between crystallographic and magnetic properties in R-M-B intermetallic phases where R is a rare earth element, yttrium or thorium and M a 3d transition metal. The presence of boron in the transition metal atomic environment dramatically modifies the magnetic properties both at macroscopic and microscopic scales. Through this experimental work, we investigated the magnetic properties of YCo4B compound, the reference compound of the Rn+mCo3n+5mB2n family, and some RCo4-xFexB. The original magnetocrystalline anisotropy of YCo4B presents both a spin reorientation and a first order magnetisation process. It also presents a great sensitivity to an applied pressure. Using neutron diffraction, we demonstrated that the iron for cobalt substitution in RCo4B compound give rise to a preferential substitution scheme. Combining these results to those of different magnetic measurements and Mössbauer spectroscopies, we determined the contributions of each crystallographic sites of transition metals to the macroscopic magnetic properties. We studied the Y1-xThxCo4B solid solution and shown the appearance of preferential thorium for yttrium substitution on one of the R crystallographic sites. These two R elements are not magnetic but the magnetic properties however drastically depend on the thorium / yttrium ratio. Through comparison to magnetic measurements under pressure, we could demonstrate that these differences originates mostly from the difference of electronic configuration between both elements and not only from structural evolution caused by the substitution. New compounds of formulae R3Co13B2 and R5Co19B6 had been recently discovered among the Rn+mCo3n+5mB2n structural family. We present studies of the synthesis conditions and the magnetic structures of some of these new phases. In particular, the Pr5Co19B6 compound presents magnetic anomalies interpreted as a spin reorientation transition occuring at low temperature. We present results of X rays absorption on selected compositions of the CeCo12-xFexB6 solid solution. In this structure, one can observe an intermediate valence state for cerium which is sensitive to the iron content. To finish, we studied the synthesis conditions of the Nd2Fe23B3 and Y3Fe62B14 metastable phases. These original structures show numerous atomic environments for iron giving rise to interesting magnetic properties. We observed unusual evolution of their magnetic properties between amorphous and crystalline state of these alloys

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Mayot, Hervé. "Contribution à l'étude cristallographique et magnétique de composés intermétalliques R–Co–B et R–Fe–B (R ≡ élément de terres rares)". Phd thesis, Grenoble 1, 2008. http://tel.archives-ouvertes.fr/tel-00399675.

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Nous nous sommes attaché à étudier les liens entre propriétés cristallographiques et magnétiques de phases intermétalliques R M-B où R est un élément de terres rares, l'yttrium ou le thorium et M un métal de transition 3d. La présence de bore dans l'environnement atomique des sites de métaux de transition, notamment, agit fortement sur les propriétés magnétiques tant à l'échelle macroscopique que microscopique.
Nous apportons une contribution à l'étude des propriétés magnétiques particulières du composé YCo4B, composé modèle et de référence de la famille Rn+mCo3n+5mB2n. L'anisotropie magnétocristalline originale de ce composé est caractérisée à la fois par une réorientation de spin et un processus d'aimantation du premier ordre. Elle s'avère également fort sensible à la pression comme l'ont montré nos mesures magnétiques. La substitution du fer au cobalt dans les composés RCo4B est possible et donne lieu à un schéma préférentiel comme l'illustre nos mesures de diffraction des neutrons. En combinant ces résultats à des mesures magnétiques diverses et de spectroscopie Mössbauer, les propriétés magnétiques de chaque site cristallographique de métaux de transition 3d ont pu être particularisées.
Nous avons étudié la solution solide Y1-xThxCo4B et montré l'existence d'une substitution préférentielle du thorium à l'yttrium sur un site cristallographique. Ces deux éléments R non magnétiques ont des effets différents sur les propriétés magnétique des composés. Par comparaison à des études magnétiques sous pression, il a été possible de montrer que ces différences sont principalement dues aux différences de configuration électronique entre le thorium et l'yttrium et peu aux évolutions structurales induites par la substitution.
De nouveaux composés de la famille structurale Rn+mCo3n+5mB2n ont été mis à jour récemment. Nous présentons des études des conditions de synthèses et des structures magnétiques de quelques phases R3Co13B2 et R5Co19B6. Le composé Pr5Co19B6 présente notamment des anomalies magnétiques interprétables comme une réorientation de spin à basse température.
Nous présentons des résultats d'absorption des rayons X réalisés sur plusieurs compositions de la solution solide CeCo12-xFexB6. Dans cette structure, le cérium présente un état de valence intermédiaire qui évolue notablement en fonction de la teneur en fer.
Enfin, nous avons précisé les conditions de synthèse de phases métastables Nd2Fe23B3 et Y3Fe62B14, très riches en fer. Ces structures originales présentent de nombreux types d'environnements atomiques du fer ce qui en fait des composés aux propriétés magnétiques intéressantes. Nous avons notamment montré les évolutions inhabituelles de ces propriétés magnétiques entre les états amorphe et cristallisé de ces alliages.

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Khan, Ayaz Arif [Verfasser]. "Dielectric reliability and spin dependent transport in Co-Fe-B/MgO/Co-Fe-B magnetic tunnel junctions / Ayaz Arif Khan. Fakultät für Physik. Abt. Experimentalphysik : Dünne Schichten und Nanostrukturen -- Fakultät für Physik". Bielefeld : Universitätsbibliothek Bielefeld, Hochschulschriften, 2011. http://d-nb.info/1010819844/34.

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Sawaf, Matthieu. "Le récepteur co-inhibiteur BTLA au cours du lupus érythémateux disséminé (LED) : aspects fondamentaux et implications thérapeutiques". Thesis, Strasbourg, 2018. http://www.theses.fr/2018STRAJ016.

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Le lupus érythémateux disséminé (LED) est une maladie auto-immune systémique caractérisée par une inflammation provoquant des lésions dans de nombreux organes tels que les reins, les poumons ou la peau. Dans cette pathologie, une activation excessive du système immunitaire conduit à la production d’auto-anticorps dirigés, le plus souvent, contre du matériel nucléaire. La différenciation des lymphocytes B (LB) en cellules productrices d’anticorps requiert une communication entre les LT et les LB. Ce dialogue est régulé par de nombreux acteurs cellulaires et moléculaires afin de permettre la mise en place d’une réponse humorale efficace en cas d’infections, mais aussi de prévenir le développement de maladies auto-immunes. Mon projet de thèse a consisté à étudier l’implication de deux de ces acteurs, l’un favorisant la différenciation des LB en plasmocytes, à savoir, les cellules T folliculaires auxiliaires (TFH) et le second régulant négativement l’activation lymphocytaire, le récepteur co-inhibiteur BTLA (pour B and T Lymphocyte Attenuator) dans le LED chez l’Homme. Au cours de cette étude, nous avons d’une part amélioré les connaissances concernant les sous-populations de TFH circulantes humaines, en décrivant que parmi les cellules TFH CXCR3-CCR6- sont retrouvées des cellules aux propriétés suppressives. De plus, nous avons suggéré que la contraction des TFH1 (CXCR3+CCR6-) au profit des TFH2 (CXCR3-CCR6-), observées chez les patients lupiques, pourrait être le reflet d’une migration des TFH1 vers les organes inflammés. D’autre part, nous avons mis en évidence un défaut fonctionnel de BTLA dans les LT CD4+ de patients lupiques. Ce défaut, restauré en normalisant le métabolisme lipidique des LT CD4+, semble associé à la sévérité de la pathologie. En parallèle de ces observations, nous avons démontré un défaut d’expression de BTLA sur les LB et les LT CD4+ régulateurs de patients lupiques. L’ensemble de nos données sont prometteuses et ouvrent de nouvelles perspectives thérapeutiques pour le traitement du LED
Systemic Lupus Erythematosus (SLE) is an autoimmune disease characterized by lesions in several organs such as kidneys, lungs and skin for instance. In this pathology, an excessive activation of the immune system leads to the production of autoantibodies targeting mainly nuclear antigens. B cell differentiation into antibody-secreting cells requires a close collaboration between T and B cells. This cross-talk is regulated by various cellular and molecular factors in order to mount an efficient humoral response in case of infection, but also to prevent autoimmune disease development. The aim of my thesis was to study two regulating factors of the B cell response, one promoting the B cell differentiation into plasma cells, i.e the follicular helper T cells (TFH) and the other one inhibiting lymphocyte activation, i.e a co-inhibitory receptor called BTLA (« B and T Lymphocyte Attenuator ») in human SLE. In this study, we first improved our knowledge concerning human circulating TFH cells, by describing among the CXCR3-CCR6- TFH cell subset, a population with suppressive capacities. Moreover, we suggested that the decreased frequency of TFH1 in lupus patients’ blood could be explained by the migration of these cells into inflamed tissues. We also highlighted a BTLA functional deficiency in lupus CD4+ T cells. This deficiency, which can be restored by normalizing the lipid metabolism, seems to be associated to disease severity. Furthermore, we described an altered expression of BTLA in lupus B cells and regulatory T cells. Altogether, our data show promising results and suggest new potential therapeutic strategies for lupus treatment

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Liu, Yijun. "Amorphisation and characterisation of multicomponent Fe-Co-Ni-Zr-B alloys during mechanical alloying". Thesis, University of Birmingham, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368795.

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Reichel, Ludwig. "Gedehnte epitaktische Fe-Co-X-Schichten (X = B, C, N) mit erhöhter magnetischer Anisotropie". Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-194953.

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Theoretische Berechnungen sagen für tetragonal gedehntes Fe-Co eine hohe magnetokristalline Anisotropie voraus, wie sie für seltenerdfreie Dauermagnetwerkstoffe vorteilhaft wäre. In dieser experimentellen Arbeit werden epitaktische Fe-Co-Schichten strukturell und magnetisch charakterisiert. Zur Untersuchung der Dehnung in diesen Schichten eignen sich AuxCu100-x-Pufferschichten besonders, da über die Stöchiometrie (x) deren lateraler Gitterparameter eingestellt werden kann. Wird Fe-Co auf einer solchen Pufferschicht abgeschieden, erfolgt aufgrund dessen hoher elastischer Energie schon in den ersten Monolagen eine vollständige Relaxation der pufferinduzierten Dehnung. In ternären Fe-Co-X-Schichten, in denen kleine X-Atome (X = B, C oder N) Oktaederlücken besetzen, wird jedoch eine spontane tetragonale Dehnung c/a bis zu 1,05 beobachtet. Entlang der gedehnten c-Achse tritt eine uniaxiale magnetokristalline Anisotropie auf, die für B- oder C-Zulegierungen von 2 at% eine maximale Anisotropiekonstante von 0,4 MJ/m³ zeigt. Wird der X-Gehalt weiter erhöht, nehmen die Kristallinität der Schichten und die magnetische Anisotropie ab. Neben der magnetokristallinen Anisotropie des Schichtvolumens wird an den Fe-Co(-X)-Schichten eine hohe Grenzflächenanisotropie beobachtet. Der Beitrag der freien Oberfläche übersteigt den der Au-Cu-Grenzfläche dabei deutlich
Theoretical calculations predict a high magnetocrystalline anisotropy for tetragonally strained Fe-Co, which would be beneficial for rare-earth free permanent magnet materials. In this experimental work, epitaxial Fe-Co films are investigated structurally and magnetically. AuxCu100-x buffer layers are very suitable to study the strain in these films since their in-plane lattice parameter can be tailored via the applied stoichiometry (x). However, when Fe-Co is deposited on such a buffer layer, the induced strain of the Fe-Co lattice relaxes completely within the first monolayers, due to its high elastic energy. In ternary Fe-Co-X films, where small atoms X like B, C or N occupy octahedral interstitial sites, a spontaneous strain c/a up to 1.05 is observed. A uniaxial magnetocrystalline anisotropy along the strained c axis appears. Their maximum anisotropy constant is 0.4 MJ/m³ for B or C contents of 2 at%. If the X content is further increased, the crystallinity and thus, the magnetic anisotropy of the films degrade. Together with the magnetocrystalline anisotropy of the films’ volumes, a high interface anisotropy is observed for the Fe-Co(-X) films. The contribution of the free surface clearly exceeds the contribution of the Au-Cu interface

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He, Yixuan. "Nucléation et magnétisme des métaux liquides Co-B en surfusion sous champ magnétique intense". Thesis, Université Grenoble Alpes (ComUE), 2019. http://www.theses.fr/2019GREAY087.

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Dans le cadre du présent travail, une étude approfondie a été menée sur les alliages Co-B en termes d'évolution de la microstructure lors d'une solidification hors équilibre avec ou sans champ magnétique ainsi que sur une transition liquide-liquide induite par la température.Un alliage hypereutectique Co-20at.%B a été sous-refroidi par la technique de l'encapsulation vitreuse. Une transition de l'hypereutectique à l'hypoeutectique a été trouvée à un sous-refroidissement critique de ∆T=119 K. Quand ∆T<119 K, une phase dendritique directionnelle primaire β-Co3B entourée par l'eutectique lamellaire régulière de α-Co+β-Co3B a été observée. Lorsque ∆T>119 K, la microstructure hypereutectique ci-dessus se transforme en structure hypoeutectique avec la phase α-Co comme phase primaire. Selon le modèle de croissance de la dendrite, le passage de l'hypereutectique à l'hypoeutectique peut être attribué à la vitesse de croissance plus élevée de la α-Co que de la β-Co3B, c'est-à-dire un mécanisme contrôlé par la croissance.La surchauffe et le refroidissement cycliques ont été effectués pour les alliages hypereutectiques sous-refroidis Co-20at.%B, eutectiques Co-18.5at.%B et hypoeutectiques Co-17at.%B. Pour chaque alliage, il y a une température critique de surchauffe Tc0 à laquelle il y a une brutale augmentation du sous-refroidissement moyen. Les mesures DSC montrent qu'il y a un pic d'absorption thermique dans le processus de chauffage, dont le pic de température est presque égal à la température critique de surchauffe, ce qui indique qu'une transition structurale liquide-liquide induite par la température se produit et doit être étroitement liée à la nucléation dans le liquide eutectique Co-B sous refroidi. L'effet de la transition structurale liquide-liquide sur la nucléation a été interprété par la récente théorie de la nucléation qui considère les structures des liquides en fusion surchauffées, et la température de surchauffe critique TcO, dépendante de la composition, a été attribuée au changement de structures préférentielles locales.Grace à une mesure in situ de l'aimantation, la transition structurale liquide-liquide induite par la température a été étudiée plus en profondeur. Une anomalie d'aimantation en terme de non dépendance de l'aimantation selon une loi de Curie-Weiss a été observée à l'état surchauffé, ce qui démontre une transition structurale liquide-liquide induite par la température. Ce comportement anormal s'est avéré être une règle universelle pour le système d'alliage binaire Co-B. Une température de transition (T0) et deux températures de Curie paramagnétiques (θ(LI), θ(LII)) correspondant à deux structures différentes des liquides sont déterminées. Les effets de l'intensité du champ magnétique sur la transition liquide-liquide et les températures de Curie paramagnétiques sont étudiés. T0 et θ(LII) ne sont pas sensibles à l'intensité du champ, tandis que θ(LI) passe à des températures plus basses avec une intensité croissante du champ magnétique. Avec une concentration croissante de Cobalt, T0, θ(LI) et θ(LII) passent à des températures plus élevées et les constantes de Curie pour le liquide I et le liquide II diminuent.Sous l'effet d'un champ magnétique imposé, un alignement morphologique a été trouvé pour la phase primaire α-Co avec son tronc primaire de dendrite ou son grand axe parallèle à la direction du champ magnétique. Les phases primaires de α-Co sont de formes cylindriques ou sphériques avec un sous-refroidissement relativement élevé, et l'application d'un champ magnétique est plus propice à l'obtention de ce type de phases α-Co. L'énergie magnétique, le couple magnétique et le temps requis pour la rotation ont été analysés théoriquement pour évaluer l'alignement magnétique et les mécanismes d'alignement. Les forces dipolaires entre les particules ont été calculées sur la base desquelles le phénomène d'auto-organisation des particules primaires de α-Co sous forme d'empilement en chaîne a été décrit
In the present work, a thorough investigation has been conducted on the Co-B alloys in terms of the microstructure evolution during non-equilibrium solidification with/without magnetic field and temperature induced liquid-liquid structure transition.A Co-20at.%B hypereutectic alloys was undercooled by the melt fluxing technique. A transition from hypereutectic to hypoeutectic was found at a critical undercooling of ∆T=119 K. When ∆T<119 K, a primary directional dendritic β-Co3B phase surrounded by the regular of α-Co+β-Co3B lamellar eutectics was found. When ∆T>119 K, the above hypereutectic microstructure changes into hypoeutectic structure with the α-Co phase as the primary phase. According to dendrite growth model, the transition from hypereutectic to hypoeutectic can be ascribed to the higher growth velocity of the α-Co phase than the β-Co3B phase, i.e., the growth-controlled mechanism.Cyclic superheating and cooling were carried out for the undercooled hypereutectic Co-20at.%B, eutectic Co-18.5at.%B and hypoeutectic Co-17at.%B alloys. For each alloy, there is a critical overheating temperature Tc0 at which there is a sharp increase of the mean undercooling. DSC measurements show that there is a thermal absorption peak in the heating process, the peak temperature of which is nearly equal to the critical overheating temperature, indicating that the temperature induced liquid-liquid structure transition does occur and should relate highly to nucleation in the undercooled Co-B eutectic melts. The effect of the liquid-liquid structure transition on nucleation was interpreted by the recent nucleation theory that considers the structures of overheated melts, and the composition-dependent overheating temperature was ascribed to the change of local favored structures.By in situ measuring the magnetization, the temperature induced liquid-liquid structure transition was further investigated. A magnetization anomaly in term of the non-Curie-Weiss temperature dependence of magnetization was observed in the overheated state, demonstrating a temperature induced liquid-liquid structure transition. This anomalous behavior was found to be a universal formula for the Co-B binary alloy system. A transition point (T0), two different Curie constants and two paramagnetic Curie temperatures (θ(LI), θ(LII)) corresponding to two distinct kinds of liquids (i.e., high-magnetization liquid I and low-magnetization liquid II) are determined. The Curie constant of liquid II was found much higher, which is attributed to the survived covalent bond below T0. The effects of magnetic field intensity on the liquid-liquid structure transition and paramagnetic Curie temperatures are studied. T0 and θ(LII) are found not sensitive to the field intensity, whereas, θ(LI) shifts to lower temperatures with the increasing magnetic field intensity. With the increased concentration of Co, T0, θ(LI) and θ(LII) shift to higher temperatures and the Curie constants for the liquid I and liquid II decrease. Based on the location of T0, a guideline was drawn above the liquidus in the Co-B phase diagram, which could provide a significant guidance to the practical melt treatment.Under an imposed magnetic field, a morphological alignment was found for the primary α-Co phase with its primary dendrite trunk or long axis paralleling to the direction of magnetic field. The primary α-Co phases are rod-like or spherical at relatively high undercooling, and the application of magnetic field is more conducive to obtain such kind of α-Co phases. The magnetic energy, magnetic torque and time required for rotation were analyzed theoretically to evaluate the magnetic alignment and alignment mechanisms. The dipolar forces between particles were calculated, based on which the phenomenon that the primary α-Co particles self-organize as chain-like stacking was described

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Lima, Valquiria Fernanda Gonçalves de. "Preparação e caracterização de nanopartículas magnéticas de Sm-Co, Nd-Fe-B, Fe-Pt e Co-Pt pelo método de agregação gasosa". Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-26112014-135553/.

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Atualmente, nanopartículas (NPs) são utilizadas em todos os ramos da tecnologia. Suas promissoras aplicações envolvem entre outros, o campo dos sensores e transdutores, mídia de gravação magnética, carreadores magnéticos de drogas medicinais. Com o objetivo de produzir NPs pelo método físico, um gerador de nanopartículas foi adaptado usando um dos canhões do sistema de magnetron sputtering, baseando-se no método de agregação gasosa. Com o gerador somos capazes de produzir NPs de diversos materiais e codepositá-las em matrizes dielétricas ou metálicas. Neste trabalho apresentamos o desenvolvimento da metodologia para a produção de nanopartículas de materiais magnéticos duros, usando alvos de SmCo5, Sm2Co17, Nd2Fe17B, FePt e CoPt. Investigamos a influência dos parâmetros de deposição (pressão, fluxo de gás e potência de sputtering), tipo de substrato e a existência de buffer e/ou codeposição, na obtenção das propriedades estruturais e magnéticas desejadas para esses materiais. As NPs produzidas são analisadas magneticamente pelo VSM e SQUID, sua morfologia e tamanho por TEM e SEM, a sua estequiometria pelo RBS, e a sua estrutura cristalina por XRD, a fim de obter nano-ímãs de alta anisotropia magnética. Da caracterização morfológica, através de microscopia eletrônica, encontramos para as NPs produzidas e estudadas diâmetros entre 5 e 17 nm. Através de análises de RBS obtemos para composição das NPs que as mesmas possuem estequiometria diferente dos alvos usados. Estudos estruturais e magnéticos mostram que para Sm-Co, Fe-Pt e Co-Pt é possível obter NPs cristalinas e com coercividade da ordem de 1 kOe.
In the recent years, nanoparticles (NPs) are being in all fields of technology. Their promising applications involve among others, the field of sensors and transducers, magnetic recording media, magnetic carriers of medicinal drugs. Aiming to produce NPs by physical method, a generator of nanoparticles was adapted using a system of guns \"magnetron sputtering\", based on the aggregation gas method. With the generator we are able to produce NPs with different types of material. In this work, we present the development of the methodology for the production of nanoparticles of hard magnetic materials, using targets of SmCo5, Sm2Co17, Nd2Fe17B, FePt and CoPt. We investigated the influence of the deposition parameters (pressure, gas flux and sputtering power), substrate type and the existence of the buffer and/or codeposition layers, to obtain the desired structural and magnetic properties for the nanoparticles. The produced NPs were magnetically analyzed by VSM and SQUID, the morphology and size by TEM and SEM, the stoichiometry by RBS and the crystal structure by XRD. The main objective of this work is to obtain nano-magnet with high magnetic anisotropy. Through the morphological characterization by electron microscopy, we found for NPs produced and studied have diameters between 5 and 17 nm. Through RBS analysis we have obtained the composition of the NPs, and also that they have different stoichiometry in relation to the used targets. Structural and magnetic studies have show that for Sm-Co, Fe-Pt and Co-Pt it is possible to obtain crystalline NPs with coercive field around 1 kOe.

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Rivier, Elodie. "La co-création de service B to B : Une étude des déterminants de l’engagement des entreprises dans un processus d’innovation des services". Electronic Thesis or Diss., Orléans, 2014. http://www.theses.fr/2014ORLE0502.

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Au vu du contexte actuel (mondialisation des échanges, concurrence, innovations technologiques…), les entreprises doivent trouver les moyens de proposer des produits et services toujours plus innovants pour se différencier. C’est pourquoi, elles font de plus en plus appel aux compétences des clients pour concevoir leurs offres qui correspondront davantage à leurs besoins. Cette pratique qui suscite un réel engouement auprès des managers est appelée « co-création ».Or, d’après la littérature, il semblerait que peu de recherches ne se sont intéressées aux raisons pour lesquelles certaines entreprises sont plus prédisposées que d’autres à co-créer des services dans le contexte interorganisationnel (Business-to Business, B to B). Pourtant, cette question est fondamentale. En effet, s’il est démontré que certains facteurs favorisent l’adhésion des clients et la gestion de projets de co-création, les organisations pourront mieux choisir des partenaires (candidats) à un projet de co-création. Ainsi, notre travail de recherche propose de répondre à la question suivante : Pourquoi certaines entreprises sont-elles plus disposées à co-créer un service alors que d’autres le sont moins ?Dès lors, après avoir réalisé un état de l’art sur la co-création de services, nous menons deux études qualitatives auprès de dirigeants et de clients B to B impliqués dans des démarches de co-création de services innovants. La troisième étude de nature quantitative est réalisée auprès d’un échantillon de prestataires de services destinés aux entreprises afin de tester nos hypothèses de recherche. Les résultats obtenus ont permis d’identifier des critères à la fois organisationnels (spécifiques à l’entreprise) et sectoriels (c’est-à-dire, relatifs au marché) explicatifs de la prédisposition et du degré d’implication des entreprises dans un processus de co-création. D’un point de vu managérial, cette recherche souligne les bonnes pratiques à mettre en place au sein des organisations avant d’initier cette démarche collaborative
In the current world context (globalization, competition, technological innovations,.), companies must look for new ways to offer more innovative goods and services. Therefore, they require customer’s competencies to design offerings that meet their needs. This practice which is raising a great deal of enthusiasm from the managers is called “co-creation”.An examination of the existing literature on services suggests that little has been done on the reasons why some companies are more disposed to engage in a B to B service co-creation process while others are less disposed to do so. Yet, this is an important issue. Indeed, if we can show that there are some criteria which can be used to identify potential co-creators and that facilitate the management of co-creation projects, then organizations could use this knowledge to select their partners in a co-creation process.In the light of the foregoing, our research study seeks to answer the following question: Why are some B-to-B service providers more disposed to co-create services than others?After a literature review on service co-creation, we conduct two qualitative studies with leaders and B to B customers involved in innovative service co-creation projects. The third study that is quantitative surveys a number of service providers in order to test our research hypothesis.Our empirical results allow us to identify firm-level and industry-level criteria relevant for explaining businesses’ willingness to engage in a co-creation process as well as their level of involvement in this process. From a managerial perspective, the present research also underlines the best practices to implement in service organizations before starting such a collaborative approach

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Thibult, Marie-Laure. "PD-1 et BTLA au coeur des lymphocytes B : du physiologique aux lymphomes". Thesis, Aix-Marseille 2, 2011. http://www.theses.fr/2011AIX20701.

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La réponse immunitaires est régulée par des molécules de co-signalisation, qui, en apportant des signaux inhibiteurs ou activateurs, modulent les fonctions lymphocytaires. Nous avons focalisé notre étude sur deux co-effecteurs et membres de la famille CD28/B7 : PD-1 (Programmed Death 1) et BTLA (B and T Lymphocyte Attenuator), tous deux décrits, à l’image de CTLA-4, comme inhibitrices de l’activation lymphocytaire T. Au cours de ma thèse, nous avons pu évaluer l’expression et le rôle de PD-1 et BTLA sur les lymphocytes B normaux et pathologiques. Dans une première partie, nos travaux ont montré que ces molécules sont exprimées à la surface des sous populations B du sang périphérique et des tissus et qu’elles sont également finement régulées au cours de l’activation B. Par la suite nous avons démontré pour la première fois que BTLA et PD-1, à l’image des cellules T, sont recrutées, après activation, au niveau du récepteur de la cellule B et qu’elles exercent un rôle inhibiteur sur l’activation de ces mêmes cellules. Dans une seconde partie, grâce au développement d’un outil en cytométrie multicouleurs, nous avons analysé, dans une cohorte de 72 lymphomes B, l’infiltrat immunitaire ainsi que l’expression de PD-1, BTLA et leurs ligands. Ce travail, par son analyse de la physiologie B d’une part et de pathologies tumorales B d’autre part, donne un nouvel éclairage sur les rôles complexes des co-récepteurs BTLA et PD-1
The immune response is regulated by co-signaling molecules, which, by providing signals inhibitors or activators, modulate lymphocyte functions. We focused our study on two co-effectors and CD28/B7 family members: PD-1 (Programmed Death 1) and BTLA (B and T Lymphocyte Attenuator), both described, like CTLA-4, as inhibitors of T lymphocyte activation. This work allowed us to evaluate the expression and the role of BTLA and PD-1 on normal and tumoral B lymphocytes. In the first part, our work has shown that these molecules are expressed on B cell subsets of peripheral blood and tissues and are also finely regulated during the B cell activation. Subsequently, we have demonstrated for the first time that BTLA and PD-1, like T cells, are recruited after activation at the B cell receptor, and they exert an inhibitory role on the activation of these cells. In the second part, through the development of a multicolor cytometry tool, we analyzed the immune infiltrate and the expression of PD-1, BTLA and their ligands in a cohort of 72 B-cell lymphomas. Taken together, these results, by his analysis of the physiology of B cell from B cell malignancies, give a new insight into the complex roles of BTLA and PD-1 co-receptors

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Aljer, Ammar. "Co-design et raffinement en B : BHDL tool, plateforme pourr la conception de composants numériques". Lille 1, 2004. https://pepite-depot.univ-lille.fr/LIBRE/Th_Num/2004/50376-2004-Aljer.pdf.

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Dans le cadre de la modélisation de systèmes complexes, la conception d'entrée ou appelée système représente le plus haut niveau d'abstraction du système global, ceci avant tout choix en terme d'implantation et de technologies. À ce tout premier stade de la conception, l'utilisation d'un langage formel de spécification est de plus en plus considéré comme le fondement d'un réel processus de validation en particulier dans le cas d'exigences de sûreté. Cette thèse met en lumière la nécessité d'une modélisation par raffinement: de la spécfication la plus abstraite vers un point de description proche de l'implémentation afin d'assurer (1) la traçabilité des besoins et des exigences, (2) une meilleure gestion du développement et (3) surtout une conception sûre des systèmes car générée par construction prouvée et ceci que ces sytèmes fassent appel à des technologies logicielles, numériques ou analogiques, voire autres. Le travail qui a été mené a consisté à mettre en perspective la taxinomie des langages ADL, le modèle de développement utilisé dans le cadre des composants électroniques et la méthode par raffinement, dite Méthode B. Ceci nous a permis de réaliser la plateforme BHDL Tool : plateforme de conception de circuits électroniques intégrant (1) une interface de description structurelle de composants électroniques, (2) un générateur de code VHDL et enfin (3) un traducteur en un langage formel pour les preuves de raffinement sous l'Atelier B.

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Aljer, Ammar Devienne Philippe Tison Sophie. "Co-design et raffinement en B BHDL tool, plateforme pourr la conception de composants numériques /". Villeneuve d'Ascq : Université des sciences et technologies de Lille, 2007. https://iris.univ-lille1.fr/dspace/handle/1908/186.

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Assis, Geovânia Cordeiro de. "Influência da concentração de sólidos totais e da temperatura no processo de co-digestão anaeróbia de resíduos sólidos orgânicos". Universidade Estadual da Paraíba, 2016. http://tede.bc.uepb.edu.br/tede/jspui/handle/tede/2415.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico - CNPq
Much of the pollution potential adjunct to human activities is related to the emission of large volumes of household and industrial waste, which, even if treated by conventional methods available, have resistant and toxic chemical species that contaminate the water environment. As a result, many efforts have been devoted to the development of alternative technologies, especially the advanced oxidation processes and, in this context, for heterogeneous photocatalysis. The tin dioxide (SnO2) stands out as an excellent photocatalytic activity material. The objective was to study the photodegradation of rhodamine B mediated by UV irradiation / SnO2 and SnO2 impregnated polystyrene nanofoams in order to evaluate the use of the catalyst impregnated polystyrene nanofoams and its reuse. The nanoparticles of SnO2 were synthesized by the polymeric precursor method, based on the Pechini method, calcination temperatures investigated oxide were 700, 800 and 900 ° C. SnO2 nanoparticles were characterized by X-ray diffraction (XRD), Diffuse Reflectance Spectroscopy (DRS), surface area analysis (B.E.T) and Transmission Electron Microscopy (TEM). The nanoparticles of SnO2 were impregnated in nanofoams polystyrene by Thermally Induced Phase Separation mechanism (TIPS), forming the photocatalysts PS/SnO2-700; PS/SnO2-800 and PS/SnO2-900 ° C. The nanofoams PS/SnO2 were characterized by XRD, B.E.T and Scanning Electron Microscopy (SEM). The dye used for testing these photocatalysts is Rhodamine B. The tests showed the effectiveness of these catalysts in the degradation of rhodamine B dye, wherein the impregnation with the polystyrene matrix increased a little photocatalytic activity of all the catalysts and the photocatalyst that obtained the best results with 94% tin dioxide was calcined at 700 ° C and the nanofoams PS/SnO2-700 ° C with 98%. Reuse tests were made that catalyst calcined at 700 ° C powder and impregnated, where it was proven that besides having a photocatalytic activity nanofoams PS/SnO2 can be removed more easily, which facilitates the separation of solution and photocatalyst.
Grande parte do potencial poluente adjunto às atividades antrópicas está relacionado com a emissão de grandes volumes de resíduos domésticos e industriais, os quais, mesmo tratados pelos métodos convencionais disponíveis apresentam espécies químicas resistentes e tóxicas que contaminam o meio hídrico. Em função disso, muitos esforços têm sido dedicados ao desenvolvimento de tecnologias alternativas, com destaque para os processos de oxidação avançada e, dentro deste contexto, para a fotocatálise heterogênea. Dentre os óxidos metálicos aplicados na fotocatalise heterogênea, destaca- se o dióxido de estanho (SnO2) na forma nanoestruturada que apresenta propriedades que favorecem a atividade fotocatalítica. O objetivo do trabalho foi preparar nanoespumas de poliestireno e impregnar nanopartículas de SnO2 para degradação fotoquímica da Rodamina B. As nanopartículas de SnO2 foram sintetizadas através do método dos precursores poliméricos, baseado no método de Pechini, as temperaturas investigadas de calcinação do óxido foram 700, 800 e 900 °C. As nanopartículas de SnO2 foram caracterizadas através de Difração de Raio-X, Espectroscopia de Reflectância Difusa (DRS), Análise de área superficial (B.E.T) e Microscopia Eletrônica de Transmissão (TEM). As nanopartículas de SnO2 foram impregnadas em nanoespumas de poliestireno através do mecanismo de Separação de Fases Induzido Termicamente (TIPS), formando os fotocatalisadores PS/SnO2-700; PS/SnO2-800 e PS/SnO2-900 °C. As nanoespumas PS/SnO2 foram caracterizadas através de DRX , B.E.T e Microscopia Eletrônica de Varredura (MEV). O corante utilizado para os testes desses fotocatalisadores foi a Rodamina B. Os ensaios mostraram a eficiência desses catalisadores na degradação do corante rodamina B, sendo que a impregnação na matriz de Poliestireno aumentou um pouco a atividade fotocatalítica de todos os catalisadores e o fotocatalisador que obteve o melhor resultado com 94 % foi o dióxido de estanho calcinado a 700 °C, bem como a nanoespuma PS/SnO2-700 °C com 98 %. Foram feitos ensaios de reuso desse catalisador, calcinado a 700 °C em pó, e impregnado, onde foi comprovado que além de ter uma atividade fotocatalítica a nanoespuma PS/SnO2 pode ser removida com mais facilidade, o que favorece a separação entre a solução e o fotocatalisador.

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Ansolin, Poliana Leopoldino. "Co-expressão das subunidades EgB8/2 e EgB8/3 do antígeno B de Echinococcus granulosus em E. coli". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2013. http://hdl.handle.net/10183/72060.

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O estágio larval do Echinococcus granulosus é o agente etiológico da hidatidose. O antígeno B (AgB) é um dos principais componentes antigênicos do liquído hidático do metacestódeo e foi caracterizado como uma lipoproteína imunogêncica de 120-160 kDa. Na presença de agentes redutores, dissocia-se em 8, 16, 24 e 32 kDa, sugerindo que é composto de multímeros de subunidades de 8 kDa. Embora a função biológica do AgB ainda não seja totalmente clara, muitos estudos demonstraram sua atuação junto à processos importantes na relação parasito-hospedeiro, por exemplo, a evasão da resposta imune do hospedeiro. Nosso laboratório já clonou e expressou em Escherichia coli cinco cDNAs que codificam subunidades do AgB, EgB8/1, EgB8/2 e EgB8/3, EgB8/4 e EgB8/5. Um trabalho recente realizado em nosso laboratório demonstrou que as subunidades recombinantes do AgB, rAgB8/1, rAgB8/2 e rAgB8/3, são capazes de autoassociarem em solução formando homo-oligômeros com características estruturais semelhantes ao AgB nativo. Entretanto, neste trabalho não foi testada a heterooligomerização das subunidades recombinantes do AgB, visto que as proteínas recombinantes purificadas foram obtidas já sob a forma de homo-oligômeros, não sendo possível a mistura destas subunidades para este fim. Este trabalho tem como objetivo investigar a possível hetero-oligomerização das subunidades recombinantes do AgB através de experimentos de co-expressão. As sequências codificadoras do AgB (EgB8/2) e (EgB8/3) de E. granulosus foram amplificadas por PCR e os produtos de PCR de ambas as sequências foram clonados no vetor de expressão (pCDF-Duet), o qual possui duas regiões com múltiplos sítios de clonagem (MCS). A fidelidade das sequências clondadas foi confirmada por sequenciamento de DNA. As proteínas recombinantes foram expressas em Escherichia coli e pela copurificação em coluna de níquel, foi possível verificar experimentalmente que as subunidades rAgB8/2 e rAgB8/3 estão interagindo entre si. A interação entre as subunidades foi confirmada pela análise por imunoblot e espectrometria de massas. Nossos resultados demostram a hetero-oligomerização das subunidades recombinantes rAgB8/2 e rAgB8/3 de E. granulosus e os dados podem fornecer um possível mecanismo de regulação na oligomerização destas subunidades. É necessário um melhor entendimento da estrutura e dos mecanismos de oligomerização do AgB para usá-lo como um importante alvo na elaboração de novas estratégias de prevenção, controle e tratamento de cestodíases.
The larval stage of Echinococcus granulosus is the etiologic agent of hydatidosis. Antigen B (AgB) is a major protein component of the metacestode hydatid fluid and was characterized as a immunogenic lipoprotein of 120-160 kDa. In presence of reducing agents, dissociates into 8, 16, 24 and 32 kDa, suggesting that their consists of multimers of 8kDa subunits. Although the biological function of AgB is still not entirely clear, numerous studies have demonstrated it engagement in important processes in the host-parasite relationship such as evasion of host immune response. Our laboratory has already cloned and expressed five cDNA encode EgB8/1, EgB8/2 e EgB8/3, EgB8/4 e EgB8/5 antigen B subunits in E. coli. Previous studies from our group demonstrated that recombinant AgB subunits are able to self-associate in solution to form homo-oligomers, presenting similar properties to native AgB. However the hetero-oligomerization of the recombinant AgB subunits were not investigated. Since purified recombinant proteins were already obtained in the form of homo-oligomers and, it was not possible to combine these subunits for this purpose. In this work we aim to investigate the possible hetero-oligomerization of the AgB subunits through co-expression experiments. The cDNA sequences enconding E. granulosus EgAgB8/2 and EgAgB8/3 by PCR and the PCR products of both sequences have been cloned in the expression vector (pCDF-Duet), which has two multiple cloning site (MCS). The fidelity of the cloned sequences was confirmed by DNA sequencing. Afterwards the recombinant proteins rAgB8/2 and rAgB8/3 expressed in Escherichia coli. By co-purification in the nickel column, it was possible to verify experimentally that the two subunits rAgB8/2 and rAgB8/3 are interacting one each other. The interaction between the subunits was confirmed by immunoblotting and mass spectrometry. Our results demonstrated the heterooligomerization of recombinant subunits rAgB8/2 and rAgB8/3 of E. granulosus and these data may help to elucidate a possible mechanism for regulation of the subunits oligomerization process. A better understanding of the structure and mechanisms of oligomerization is necessary since that the AgB as an important target in the development of new strategies for prevention, control and treatment of cestodiasis.

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Novák, Jiří. "Metody FFD". Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2017. http://www.nusl.cz/ntk/nusl-318794.

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The diploma thesis deals with the topic of free-form deformations. The main goal of this work were elaboration of theoretical knowledge about this issue and the programming of selected methods od free-form deformations. The first part describes the required spline theory, matrix calculus and free-form deformations. The resulting version shows three programs. The first program compares the selected free-form deformation methods to the example of the 4x4 control point grid. The second program serves as a generalization for the general case of grid of control points. The last program is based on direct manipulation of arbitrary surface point and following recomputation of the control points to obtain demanded shape.

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Mwakyusa, Lwitiko Pholds [Verfasser], e Richards B. [Akademischer Betreuer] S. "Development and Characterization of Co-evaporated CZTSe solar cells / Lwitiko Pholds Mwakyusa ; Betreuer: B. S. Richards". Karlsruhe : KIT-Bibliothek, 2019. http://d-nb.info/1200471334/34.

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SILVA, Gustavo Souza de Alencar e. "Sinterização por SPS de pós de W-C-CO-B preparados por moagem de alta energia". Universidade Federal de Alfenas, 2016. https://bdtd.unifal-mg.edu.br:8443/handle/tede/1057.

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Os carbetos de tungstênio com matriz de cobalto são uns dos mais antigos produtos comerciais da metalurgia do pó. Estes compósitos são usados para diferentes aplicações dentre as quais se destacam a fabricação de componentes de corte e abrasivos. Tais materiais são constituídos por partículas de carbeto de tungstênio e cobalto metálico ligados pela sinterização via fase líquida e podem ser produzidos por reações químicas convencionais. As técnicas de moagem de alta energia são amplamente utilizadas para a síntese de compostos cerâmicos. O presente trabalho visou a realização de estudos de moagem de alta energia e de sinterização de misturas de pós de carbeto de tungstênio dopados com cobalto e boro. A etapa de moagem das misturas de pós elementares de W-50C (%-at.) foi realizada em um moinho de bolas planetário Fritsch P-5 utilizando esferas (10 mm de diâmetro) e vaso de WC-Co, velocidade de 200 rpm e uma relação de massas esferas-pós de 10:1. O tempo de moagem foi variado: 20, 60, 180 e 600 min. Na sequência, os pós de Co e de B foram misturados com os pós moídos de W-50C (%-at) e processados em um moinho Spex por 5 min. Seguindo, os materiais foram sinterizados em atmosfera controlada à 1450oC para a obtenção de corpos cilíndricos com altura de 1-3 mm e diâmetro de 10 mm. Os pós-moídos e os produtos sinterizados foram avaliados com o auxílio das técnicas de difração de raios X (DRX), microscopia eletrônica de varredura (MEV), espectrometria por dispersão de energia (EDS) e ensaios mecânicos (compressão diametral e dureza Vickers). Picos de carbono desapareceram após 180 min de moagem, enquanto que o pico principal do tungstênio foi deslocado para a direção de menores ângulos de difração em pós de W-50C moídos por 600 min. Ainda, os picos de tungstênio foram alargados e tiveram suas intensidades reduzidas em misturas de pós de W-50C moídos por 600 min, sugerindo que os átomos de carbono ficaram dissolvidos na estrutura cristalina do tungstênio para formar soluções sólidas supersaturadas. Amostras densas (> 96% da massa específica teórica) com microestruturas formadas pela fase WC como matriz além de precipitados ricos em boro e de W2C foram obtidos após spark plasma sintering das misturas de pós contendo adição de boro. As amostras sinterizadas apresentaram valores de dureza Vickers entre 1841 HV e 2191 HV, as quais foram mais pronunciadas para as cerâmicas mais ricas em boro. Similarmente à cerâmica convencional de WC-6Co, nenhum efeito foi encontrado sobre a adição de boro no módulo elástico das cerâmicas avaliadas, as quais ficaram próximas de 500 GPa. Ao contrário, a resistência compressiva das cerâmicas de WC-6Co contendo adição de boro ficou inferior a 500 MPa.
Tungsten carbides in cobalt matrix are one of the earliest commercial products of powder metallurgy. These composites are used for different applications among which are highlighted the manufacture of cutting components and abrasives. These composites consist of tungsten carbide and metallic cobalt particles bound by sintering through the liquid phase and they can be produced by conventional chemical reactions. Mechanical alloying techniques are widely used for the synthesis of ceramic compounds. The present work aims to perform studies of mechanical alloying and sintering of powder mixtures of tungsten carbide doped with cobalt (6 wt.-%) and boron (0.2 and 0.5 at.%). Ball milling of W-50C (at.-%) elemental powder mixtures was performed in a planetary Fritsch P-5 ball mill using WC-Co balls (10 mm diameter) and vial (500 mL), rotary speed of 200 rpm, and a ball-to-powder weight ratio of 10:1. The milling time was varied: 20, 60, 180 and 600 minutes. Following, the powders of Co and B were mixed for 5 min in a Spex mill together the previous mechanically alloyed W-50C (at.-%) powders. Afterwards, the as-milled powders were consolidated by spark plasma sintering (SPS) at 1450°C under controlled atmosphere to obtain cylindrical bodies with height of 1-3 mm and 10 mm diameter. The as-milled powders and sintered products were evaluated using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), and mechanical tests (diametrical compression and Vickers hardness). Peaks of carbon disappeared after milling for 180 min whereas the major W peak was shifted toward the lower diffraction angles in W-50C powders milled for 600 min. In addition, the peaks of W were broadened and their intensities reduced after milling for 600 min, suggesting that the carbon atoms were dissolved into the W lattice in order to form supersaturated solid solutions. SPS process of mechanically alloyed W-50C powders containing Co and B produced dense samples (> 96% of theorical specific mass) which presented microstructures formed by the WC phase as matrix beside the B-rich and W2C precipitates. SPS samples presented Vickers hardness values between 1841 HV and 2191 HV which were more pronounced for B-richer ceramics. For the evaluated ceramics, no effect of boron addition on the elastic module was found, which were close to 500 GPa. On the other hand, the compressive strenght of W-50C ceramics containing Co and B addition were lower than 500 MPa.
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES

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Chakrabarti, Ajoy Chuni Carleton University Dissertation Biology. "One-step conversion of cellulose to fructose using co-immobilized cellulase, B-glucosidase and glucose isomerase". Ottawa, 1988.

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Chopra, Manu. "Raman spectroscopic studies of (A) the Co-C bond in vitamin B## and model compounds, (B) inorganic matrices-encapsulated metallocomplexes, and (C) molecular hydrogen compounds". Diss., Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/30565.

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Souza, Ana Camila Oliveira. "Avaliação e tratamento da paracoccidioidomicose experimental utililizando diferentes doses de anfotericina B nanoestruturada em polímeros de ácido poli(lático-co-glicólico)". reponame:Repositório Institucional da UnB, 2012. http://repositorio.unb.br/handle/10482/11781.

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Tese (doutorado)—Universidade de Brasília, Faculdade de Medicina, Programa de Pós-Graduação em Patologia Molecular, 2012.
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O desenvolvimento de nanopartículas poliméricas tem se tornado uma importante estratégia para otimização da eficácia terapêutica de inúmeros fármacos, podendo ampliar sua atividade e reduzir sua toxicidade. A nanoestruturação da Anfotericina B (NANO-D-AMB), importante antifúngico usado no tratamento de algumas micoses sistêmicas, como a paracoccidioidomicose e a candidíase, apresentou eficácia no tratamento da paracoccidoidomicose (PCM) experimental, com atividade antifúngica similar à da anfotericina B deoxicolato (D-AMB) e possibilitando um menor número de aplicações. Nesse contexto, o objetivo deste estudo foi determinar a capacidade antifúngica e biocompatibilidade desta nova formulação in vitro, bem como comparar a eficácia terapêutica de diferentes doses de NANO-D-AMB com D-AMB e Ambisome® no combate a PCM murina. Para isso, determinou se in vitro a concentração mínima inibitória de NANO-D-AMB em leveduras de Paracoccidioides brasiliensis e avaliou-se sua capacidade hemolítica e citotóxica em macrófagos peritoniais. Realizou se também a infecção de camundongos BALB/c e posteriormente o tratamento com as nanopartículas em diferentes doses, D- AMB e Ambisome®. Foi observado que NANO-D-AMB apresentou eficácia antifúngica in vitro similar a Ambisome®, bem como menor indução de hemólise e menor citotoxicidade em comparação a D-AMB. Além disso, foi observada similar capacidade antifúngica in vivo em relação à D-AMB e Ambisome®, sem indução de alterações histológicas e nas funções renais e hepáticas, com a vantagem de permitir uma diminuição em 25% na quantidade de anfotericina B injetada. O tratamento com NANO-D-AMB e Ambisome® ajudaram a modular positivamente a resposta imunológica em favor do hospedeiro. Além disso, verificou-se que o uso de sobredoses não provocou toxicidade aguda. Juntos esses resultados sugerem NANO-D-AMB como uma alternativa ao uso de D-AMB e Ambisome®. _______________________________________________________________________________________ ABSTRACT
The development of polymeric nanoparticles has become an important strategy for optimizing the therapeutic efficacy of many drugs, as it may expand their activities and reduce their toxicity.- The nanostructuring of Amphotericin B (NANO-D-AMB), an important antifungal agent used to treat some systemic mycoses such as paracoccidioidomycosis and candidiasis, showed efficacy in treating experimental paracoccidoidomicose (PCM), with antifungal activity similar to that of amphotericin B deoxycholate (D-AMB) and allowing a fewer number of applications. In this context, the aim of this study was to determine the antifungal activity of this new formulation and its biocompatibility in vitro and to compare the efficacy of different doses of NANO-D-AMB between D-AMB and Ambisome® in combating murine PCM. For this, it was determined in vitro minimum inhibitory concentration of NANO-D-AMB in Paracoccidioides brasiliensis yeasts, and it was evaluated its hemolytic and cytotoxic activities in peritoneal macrophages. Also, BALB/c mice were infected and then treated with the nanoparticles in different doses, D-AMB and Ambisome®. It was observed that NANO-D-AMB exhibited in vitro antifungal efficacy similarly to Ambisome® and induced lower hemolysis and cytotoxicity compared to D-AMB. Moreover, it was observed similar in vivo antifungal capacity in relation to D-AMB and Ambisome® without inducing changes in renal and hepatic histology and function, with the advantage of a 25% decrease in the amount of amphotericin B injected. Treatment with NANO-D-AMB and Ambisome® helped to positively modulate the immune response in favor of the host. Furthermore, it was found that the use of overdoses did not cause acute toxicity. Together, these results suggest NANO-D-AMB as an alternative to the use of D-AMB and Ambisome®.

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Henge, Dennis [Verfasser], B. [Akademischer Betreuer] Albert e J. [Akademischer Betreuer] Schneider. "Metallphosphide mit Mg, Mn,Cu, Co und Ni als thermoelektrische Materialien / Dennis Henge ; B Albert, J Schneider". Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2016. http://d-nb.info/112120693X/34.

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Lacombe, Karine. "La co-infection VIH - hépatite B chronique : déterminants de la fibrose hépatique et impact des traitements antiviraux". Paris 6, 2006. http://www.theses.fr/2006PA066189.

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De par l’utilisation à large échelle des nouvelles trithérapies antirétrovirales depuis 1996, la morbidité due à l’infection par le virus de l’immunodéficience humaine (VIH) a évolué vers l’émergence de nombreuses pathologies chroniques. Parmi celles-ci, la co-infection avec un virus hépatotrope (hépatites B, C et Delta) est fréquente, du fait de modes de transmission proches et du risque accru d’évolution vers la chronicité en contexte d’immunodépression. Première cause de maladie terminale du foie par hépatocarcinome dans le Monde, l’hépatite B chronique (VHB) concerne actuellement 10% des patients infectés par le VIH. Les déterminants de l’évolution complexe de cette pathologie, et en particulier de la fibrose hépatique dans le contexte du VIH, ont été peu étudiés, alors que les enjeux en termes de pronostic à long terme et de thérapeutique commune VIH-VHB sont importants. Nous nous sommes intéressés dans notre travail de recherche à l’étude de deux groupes de facteurs de risque de fibrose hépatique en raison de leur impact en termes de prise en charge clinique et thérapeutique des patients co-infectés VIH-VHB : les facteurs liés au VHB lui même et ceux liés aux comorbidités hépatiques associées. Considérant que l’amélioration des connaissances en matière de thérapeutique antiVHB était primordiale pour la maîtrise de la fibrose hépatique, nous nous sommes conjointement intéressés à l’évaluation du Ténofovir disoproxil fumarate, analogue nucléotidique de la transcriptase inverse présentant une double activité anti-VIH et anti-VHB. Nous avons ainsi montré l’importance du génotype du VHB comme facteur de fibrose hépatique, et en particulier du génotype G, fortement associé à un degré avancé de fibrose dans notre population. L’impact des co-morbidités hépatiques a ensuite été analysé à partir des co-infections avec d’autres virus hépatotropes tels que ceux des hépatites C (VHC) ou Delta (VHD). En présence d’une réplication active du virus de l’hépatite Delta, celles du VHC et du VHB semblent partiellement inhibées, mais la sévérité de la fibrose hépatique est déterminée par la présence de l’hépatite C même chez les patients conjointement infectés par le VHD. Enfin, nous avons étudié la dynamique de décroissance du VHB lors du traitement par Ténofovir disoproxil fumarate. Cette décroissance s’est révélée être biphasique et principalement influencée par la charge virale initiale du VHB. Le degré de fibrose hépatique et les caractéristiques virologiques des patients n’ont eu aucune conséquence clinique sur la réponse au traitement. Notre travail s’est ouvert sur des perspectives de recherches complémentaires qui nous permettront à terme de posséder assez d’éléments sur l’association entre fibrose hépatique et co-infection VIH-VHB pour proposer un modèle prédictif d’évolution de la co-infection VIH-VHB à l’ère des trithérapies antirétrovirales puissantes. Grâce aux données de qualité de vie et aux données médico-économiques recueillies prospectivement au cours du suivi de cohorte, ce modèle pourrait permettre de compléter les recommandations de prise en charge des patients co-infectés par le VIH et l’hépatite B chronique.

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Moret, Frédéric. "Elaboration d'alliages microcristallisés par dévitrification des verres métalliques Ni-Nb et Co-Nb-B trempés sur rouleau". Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb376081326.

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Feghali, Elias. "Nouveaux procédés catalytiques pour le recyclage de déchets ligno-cellulosiques, de polymères et de dérivés du CO₂". Thesis, Paris 11, 2015. http://www.theses.fr/2015PA112173/document.

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L’objectif de cette thèse était la mise au point de nouvelles méthodes de synthèse innovantes permettant le recyclage de déchets carbonés ou l’utilisation de matières premières renouvelables, ceci afin d’améliorer la durabilité du secteur de la chimie industrielle et de réduire sa dépendance aux ressources fossiles. Dans cette optique, le travail a été réalisé en suivant trois axes de recherche principaux visant la mise au point de nouveaux procédés catalytiques pour la valorisation de l’acide oxalique, un dérivé du CO2, de déchets de matériaux polymères ainsi que de la biomasse. Afin d’atteindre les objectifs fixés, une stratégie basée sur le clivage réducteur des liaisons C–O et utilisant la réaction d’hydrosilylation catalysées par B(C6F5)3 a été adoptée. Cette stratégie a permis en premier lieu d’obtenir, à partir de l’acide oxalique, une large gamme de produits ayant différents degrés d’oxydation allant de l’acide glyoxylique trisilylé jusqu’à l’éthane. Il a été montré ensuite que le système B(C6F5)3-hydrosilane permet la dépolymérisation sélective de déchets plastiques (tels que PLA, PET et PC-BPA) ainsi que de polyesters bio-sourcés tels que l’acide tannique et la subérine, en une variété de molécules comprenant des alcools, des phénols et des alcanes. Enfin, l’efficacité de B(C6F5)3 comme catalyseur d’hydrosilylation sélectif a été démontrée pour le clivage réducteur des modèles de motifs α-O-4 et β-O-4, principales liaisons dans la lignine. Cette réaction a pu être extrapolée à la lignine issue du bois et une nouvelle démarche permettant l’obtention de produits aromatiques purs à partir de la lignine a été développée
The objective of this thesis was the development of new innovative synthetic methods for recycling waste carbon compounds or renewable raw materials to improve the sustainability of the industrial chemical sector and reduce its dependence on fossil resources. In this context, the work has been performed following three main areas of research intended for the development of new catalytic processes for the valorization of oxalic acid, derived from CO2, waste polymer materials and biomass. To achieve these objectives, a strategy based on the reductive cleavage of C–O bonds using the hydrosilylation reactions catalyzed by B(C6F5)3 was selected. First, this strategy resulted in the generation of a wide range of products with different degrees of oxidation, from oxalic acid, ranging from trisilylated glyoxylic acid to ethane. Afterwards, the system B(C6F5)3-hydrosilane allowed the selective depolymerization of waste plastics (such as PLA, PET, PC-BPA) as well as bio-based polyesters such as tannic acid and suberin, to a variety of molecules including alcohols, phenols and alkanes. Finally, it has been shown that B(C6F5)3 is an efficient and selective hydrosilylation catalyst for the reductive cleavage of α-O-4 and β-O-4 models, the main linkages in lignin. This reaction was successfully transposed to lignin derived from wood and a new process for obtaining pure aromatic products from lignin has been developed

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Martin, Quigley Christina M. "Characterization of Occult Hepatitis B Virus Infection in HIV-Positive Individuals". University of Cincinnati / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1307441402.

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Kojukhov, Artyom. "Assessment of disulfide bond formation during co-translational folding of synonymous codon variants of recombinant gamma-B crystallin". Cleveland State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=csu152571031230488.

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Kocon, Laurent. "Elaboration par dépôt chimique autocatalytique d'alliages amorphes (Co-B) et caractérisation de leurs propriétés magnétiques à haute fréquence". Grenoble INPG, 1992. http://www.theses.fr/1992INPG0136.

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Le sujet de cette these est la realisation de materiaux destines a l'absorption des ondes electromagnetiques. Le choix s'est porte sur des composites dont la charge formee de particules magnetiques isolees, interagit avec les ondes electromagnetiques incidentes en engendrant un phenomene de pertes d'origine magnetique. L'elaboration de ces particules agregataires par la methode electroless fait l'objet d'une etude approfondie. Le procede de depot chimique autocatalytique, dit electroless, permet de revetir, en milieu aqueux et a des temperatures inferieures a 100c tout type de substrat, granulaire ou massif, d'une couche d'alliage. Cette methode fut donc etudiee et utilisee pour recouvrir des microbilles de verre de diametre inferieur a 15 microns d'un depot magnetique de cob amorphe, donc a tres faible anisotropie magnetique, et d'epaisseur controlee de l'ordre de quelques microns. Les microbilles, ainsi elaborees, sont conductrices. Pour isoler individuellement chacune de ces particules, une methode de passivation est utilisee. La couche d'oxyde, formee a la surface des particules magnetiques, grace au traitement de passivation, assure une isolation efficace des charges et supprime, ainsi, tout risque de percolation electrique meme pour des taux de charge eleves en agregataire. Une trop grande conductivite du composite empecherait les ondes de penetrer dans l'echantillon et d'etre absorbees par pertes magnetiques. Les analyses effectuees sur le materiau ont consiste a determiner sa composition et ses proprietes magnetiques dont la permeabilite a haute frequence

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Valcanover, João Alberto. "Propriedades estruturais e magnéticas de compostos intermetálicos Nd-Fe (Co)-Ru-B-C na fase tetragonal (P42/mmm)". Florianópolis, 2009. http://repositorio.ufsc.br/xmlui/handle/123456789/93279.

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Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências Físicas e Matemáticas. Programa de Pós-graduação em Física
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Neste trabalho foi realizado um estudo das propriedades magnéticas intrínsecas e estruturais de quatro sistemas de ligas: Nd16Fe76-xRuxB8, Nd16-Co76-xRuxB8, Nd16Co76-xRuxC7B e Nd16Co72-xRuxC11B. O foco de atenção é particularmente a fase tetragonal f (2:14:1) (grupo de espaço P42/mmm). Para isto foram utilizadas as técnicas experimentais de difração de raios-X, espectroscopia Mössbauer, medidas de magnetização, termogravimetria, calorimetria diferencial de varredura e análise metalográfica. As amostras foram preparadas por fusão à arco voltaico a partir da mistura nominal dos elementos de pureza eletrolítica (99,9 %). O propósito desta investigação é observar o efeito da substituição parcial do Fe ou Co pelo Ru nas propriedades magnéticas destas ligas, além de analisar comparativamente o efeito da contribuição da sub-rede 3d com a presença de Fe ou Co, com a introdução de um elemento 4d, o Ru (isoeletrônico do Fe), nas propriedades magnéticas desses materiais. Desde o advento dos chamados supermagnetos, à base de terras raras com metais de transição, surgiu uma grande expectativa de produzir materiais magnéticos de alto desempenho e baixo custo, e um grande esforço foi empreendido para encontrar novos materiais ainda melhores. Inicialmente grande atenção foi dada aos compostos à base de boro, os chamados boretos. Com a descoberta de que o boro pode ser substituído pelo carbono, surgiu um grande interesse pela família dos carbetos, gerando em seguida os boro-carbetos, que apresentam coercividades muito maiores do que os boretos convencionais. Uma grande anisotropia magnetocristalina ocorre nesses sistemas, devido basicamente à contribuição da sub-rede dos terras raras. Compostos do tipo R2Fe14B e R2Fe14C têm campos cristalinos idênticos e a interação de troca 3d-4f é praticamente a mesma em ambos. A substituição de carbono por boro reduz a temperatura de Curie em cerca de 30-40 K, e o momento magnético médio diminui. Por outro lado, os custos de produção são bem menores para os carbetos, que apresentam ainda elevada magnetização de saturação e alta suscetibilidade diferencial em campos magnéticos intensos, o que ainda não é bem esclarecido. Neste sentido o presente estudo é dedicado à salientar as peculiaridades desses intermetálicos focalizando o efeito da variação da constituição química da sub-rede 3d (ao trocar Fe por Co e/ou Ru) e da concentração dos constituintes em boretos e correspondentes carbetos assim como em suas combinações (boro-carbetos).
In this work is performed a study of the structural and magnetic properties of four alloy systems: Nd16Fe76-xRuxB8, Nd16Co76-xRuxB8, Nd16Co76-x-RuxC7B and Nd16Co72-xRuxC11B. The focus of attention is particularly on the f phase (2:14:1) (space group P42/mmm). For this purpose the experimental techniques of X-ray diffraction, Mössbauer spectroscopy, magnetization measurements, thermogravimetry, differential scanning calorimetry and metalograhic analysis were used. The samples were prepared by arc melting the nominal mixtures of the elements of electrolytic purity (99.9%). The purpose of this investigation is to observe the effect of the partial substitution of Fe or Co by Ru on the magnetic properties of these alloys. Moreover to analyze comparatively the effect of the contribution of the 3d sublattice with the presence of Fe or Co, with the introduction of a 4d element, Ru (isoelectronic of Fe), on the magnetic properties of these materials. Since the advent of the so-called supermagnets, based on the rare earth with transition metals, there is a large expectation for the production of low cost and high performance magnetic materials and a great effort was devoted in obtaining even better new materials. Initially great attention was given to the compounds based on boron, the borides. With the discovery that boron can be replaced by carbon, it arises a great interest for the family of carbides, giving rise to the borocarbides, which have coercivities much larger than conventional borides. A large magnetocrystalline anisotropy occurs in these systems, basically due to the contribution of the rare earth sublattice. Compounds like R2Fe14B and R2Fe14C have identical crystalline fields and the exchange interaction 3d-4f is practically the same in both of them. The substitution of carbon for boron decreases the Curie temperature in about 30-40 K, and the average magnetic moment has a small decrease. On the other hand the production costs are much smaller for the carbides, which have a large saturation magnetization and an extraordinarily high differential susceptibility in high magnetic fields, which still is not well understood. In this sense, the present study is devoted to highlighting the peculiarities of the magnetic properties of these intermetallics focusing on the effect of the change in the chemical composition of the 3d sublattice (by changing Fe or Co by Ru) and of the concentration of constituents in the borides and corresponding carbides as well as in their combinations (boro-carbides).

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Benziane, Boubacar. "Contrôle de l' expression apicale du co-transporteur NKCC2 : rôle des interactions protéine-protéine". Paris 6, 2006. http://www.theses.fr/2006PA066005.

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Ponce, de Leon Rodriguez Maria del Carmen. "Développement d’un modèle in vitro d’inflammation intestinale par l’utilisation de lignées cellulaires humaines en co-culture pour l’étude des interactionsavec les micro-constituants alimentaires". Thesis, Montpellier, 2019. http://www.theses.fr/2019MONTG009/document.

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L’épithélium intestinal, siège de l’absorption des (micro)-nutriments est aussi le premier système de défense de l’organisme. Un déséquilibre dans l’homéostasie peut être à l’origine d’une réaction inflammatoire associée à des défauts de la barrière intestinale et de la fonction immunitaire, ainsi qu’une malabsorption des nutriments, comme rencontré dans les MICI (Maladies Inflammatoires Chroniques de l’Intestin), dans les stratégies de fortification en micronutriments et les pathologies non transmissibles (obésité). Il est donc important de trouver des moyens d’action, via l’alimentation par exemple, pour prévenir ou au minima réduire, les conséquences nutritionnelles et pathologiques de l’inflammation intestinale, et de comprendre les mécanismes impliqués. Parmi les modèles d’études de l’intestin, les modèles in vitro de culture cellulaire sont de plus en plus utilisés et permettent d'évaluer les mécanismes moléculaires d'une manière simple et reproductible et de réduire l'expérimentation animale.Dans ce contexte et dans le but d’étudier l’interaction de composés bioactifs de l’alimentation avec l’intestin en état d’inflammation, le premier objectif de ce travail de thèse a été la mise au point d’un modèle in vitro d’intestin enflammé associant en co-culture deux lignées intestinales humaines : les Caco-2 TC7 (entérocytes) et HT29-MTX (cellules caliciformes) et une lignée immunitaire de macrophages (THP1). Plusieurs marqueurs d’inflammation ont été évalués et nous avons pu montrer que le modèle de tri-culture répondait à un stimulus inflammatoire (LPS/IFNγ), par une augmentation de la production de cytokines pro-inflammatoires (TNF-α, IL6 et IL8) et d’enzymes (INOS et COX2) ainsi que l’expression de leurs gènes. Par ailleurs, une augmentation de la perméabilité épithéliale via une altération des jonctions serrées (TJs) a également pu être mise en évidence ainsi qu’une surproduction de mucus, lesquels sont des caractéristiques reconnus d’inflammation.Le deuxième objectif était d’étudier l’interaction de la β-cryptoxanthine (BCX), caroténoïde des agrumes, lipophile et anti-oxydant, avec le modèle enflammé. Nous avons utilisé pour solubiliser la BCX deux types de micelles (artificielles et physiologiques) et étudié les marqueurs d’inflammation. Bien qu’il semble d’après les résultats préliminaires que les micelles de BCX montrent une tendance à diminuer la production de certaines cytokines (IL6 et IL8), le rôle des constituants des micelles (Tween 40 ou sels biliaires/phospholipides) dans ce phénomène observé et dans la perméabilité épithéliale reste à clarifier par la suite
The intestinal epithelium, main place of the absorption of (micro)-nutrients is also the first body's defense system. An imbalance in homeostasis can lead to an inflammatory reaction associated with defects in the intestinal barrier and immune function as well as malabsorption of nutrients, as seen in IBD (Inflammatory Bowel Diseases), in micronutrient fortification strategies and noncommunicable diseases (obesity). It is therefore important to find ways of action, for example through diet, to prevent or at least reduce the nutritional and pathological consequences of intestinal inflammation, and to understand the mechanisms involved. Among intestinal models, in vitro cell culture models are increasingly used and allow to evaluate the molecular mechanisms in a simple and reproducible way and to reduce animal experimentation.In this context and in order to study the interaction of dietary bioactive compounds with the intestine in state of inflammation, the first objective of this work was the development of an in vitro model of inflamed intestine combining in co-culture two human intestinal cell lines: Caco-2 TC7 (enterocytes) and HT29-MTX (goblet cells) and an immune cell line of macrophages (THP1). Several inflammation markers were evaluated and we were able to show that the tri-culture model responded to an inflammatory stimulus (LPS / IFNγ), by increasing the production of pro-inflammatory cytokines (TNF-α, IL6 and IL8) and enzymes (INOS and COX2) as well as the expression of their genes. In addition, an increase of epithelial permeability via tight junctions (TJs) alteration has also been demonstrated, as well as overproduction of mucus, which are recognized inflammation characteristics.The second objective was to study the interaction of β-cryptoxanthin (BCX), a lipophilic and antioxidant carotenoid of citrus, with the inflamed model. To solubilize BCX, we used two types of micelles (artificial and physiological) and studied markers of inflammation. Although it appears from the preliminary results that BCX micelles show a tendency to decrease the production of some cytokines (IL6 and IL8), the role of micelle constituents (Tween 40 or bile salts / phospholipids) in the phenomenon observed and in the epithelial permeability remains to be therefore clarified

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Santos, Patricia Brissi. "Efeitos da adição de surfactante e moagem de alta velocidade em pós magnéticos à base de Pr-Fe-B obtidos via HDDR". Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/85/85134/tde-26012012-145626/.

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Esse trabalho teve como objetivo verificar o efeito da adição do ácido oléico na moagem de alta velocidade/energia na obtenção de pós magnéticos em escala nanométricas da liga Pr12Fe65,9Co16B6Nb0,1. A primeira etapa deste trabalho, envolveu a obtenção de pós magnéticos por meio do processo de hidrogenação, desproporção, dessorção e recombinação (HDDR), utilizando a pressão de H2 de 930 mbar (hidrogenação e desproporção) e temperatura de dessorção e recombinação de 840 ºC. Inicialmente, os pós HDDR foram submetidos à moagem de alta velocidade/energia a 900 rpm, com variação do volume do meio de moagem (ciclohexano) sem adição de ácido oleico. Em seguida, os pós HDDR foram submetidos à moagem com adição de ácido oleico, variando o tempo de moagem. Após a moagem, foi realizado tratamento térmico dos pós a 700 ºC ou 800 ºC durante 30 min., com a finalidade de cristalização do pó. Foi verificado que, a utilização de 6,6 ml de ciclohexano como meio de moagem e com adição de ácido oleico há uma melhora na eficiência da moagem dos pós. Para adições de surfactante, de 0,02 a 0,05 ml e tempos de moagem até 360 minutos, não ocorre a aglomeração dos pós magnéticos no pote de moagem, obtendo acima de 90% de eficiência na moagem. A segunda etapa deste trabalho envolveu a caracterização dos pós magnéticos: utilizando magnetômetro de amostra vibrante, microscopia eletrônica de Varredura, microscopia eletrônica de transmissão e difração de raios-X. Os resultados obtidos mostraram que a adição de ácido oléico na moagem de alta velocidade/energia proporciona uma melhora nas propriedades magnéticas. Com a variação do tempo de moagem a fase Fe-α presente no pó HDDR apresenta diminuição no tamanho do cristalito (de 35 para ~ 10 nm) enquanto que, na fase Pr2Fe14B verifica-se menor grau de cristalinidade.
This work verified the effect caused by adding the surfactant in the high speed/energy milling in order to obtain Pr12Fe65.9Co16B6Nb0.1 magnetic nanopowders. The first part of this work involved the magnetic powder obtainment through the process of hydrogenation, disproportionation, desorption and recombination (HDDR). The pressure of H2 during the hydrogenation and disproportion steps was 930 mbar and the temperature of desorption and recombination was 840 ºC. Initially, the HDDR powders were subjected a highspeed milling process at 900 rpm, with quantity variations of the milling medium (cyclohexane) and without the addition of oleic acid. Then, the HDDR powders were subjected to the milling process with the addition of oleic acid and with milling time variations. After the milling process, heat treatments of the powder were carried out at 700 °C or 800 °C for 30 minutes in order to obtain the crystallization of the powder. By performing the procedures, it was verified that the milling efficiency improved with the addition of 6.6 ml of cyclohexane as the milling medium and with the addition of oleic acid. It was determined that for the surfactant additions of 0.02 ml to 0.05 ml, with a milling time of up to 360 minutes, powder agglomeration does not occur in the milling pot and the milling efficiency is higher than 90%. The second stage of this work involved the magnetic powders characterization obtained by using vibrating sample magnetometer, scanning electron microscopy, transmission electron microscopy and X-ray diffraction. Through the characterizations it was found that the powders magnetic properties improved when the addition of oleic acid in a high-speed /energy milling occurred. It was also verified that the α-Fe phase, present in the powder, shows a crystallite size decrease (from 35 nm to ~ 10 nm) when the time milling variation occurred; meanwhile, the crystallinity degree was lower in the Pr2Fe14B phase when the time milling variations was carried out.

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Hammond, Robert Paul. "The structural chemistry of the stuffed tridymites A[BPO4] (A=Na; Ag; b=Be, Co, Zn) and A[BCO4] (A=Na, K; B=Al, Fe; C=Si, Ge) /". *McMaster only, 1996.

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42

Oliveira, Mara Cristina Lopes de. "Preparação de ímas HDDR e ligas de Pr-Fe-Co-B-Nb-M (M=Al, P, Cu, Ga e/ou Gd) e caracterização de suas propriedades magnéticas e resistência à corrosão". Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/85/85134/tde-21092009-103331/.

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O processo HDDR tem-se mostrado de grande interesse para a produção de ímãs à base de terras raras e polímeros. Apresenta vantagens comerciais quando comparado com os ímãs sinterizados convencionais, por exemplo, pela facilidade e menores custos de produção. Com o desenvolvimento de pós anisotrópicos, utilizando praseodímio, as expectativas em relação a este processo aumentam e, também, a necessidade de se estudar novas composições e adições. Neste trabalho, foram investigadas as propriedades magnéticas de ímãs moldados com resina, preparados com pós de ligas magnéticas de PrFeB, usando o processo HDDR. A liga magnética padrão utilizada foi a Pr14FebalCo16B6Nb0,1. Adições de elementos de liga como fósforo, cobre, alumínio, gálio e gadolíneo foram realizadas com o objetivo de melhorar as propriedades magnéticas do material padrão. A caracterização microestrutural dos ímãs foi realizada por microscopia óptica e MEV. A complexidade da microestrutura influencia o comportamento eletroquímico das ligas magnéticas. A literatura sobre este assunto é escassa. Assim, a resistência à corrosão das diferentes ligas preparadas ao longo do trabalho foi avaliada por espectroscopia de impedância eletroquímica e curvas de polarização potenciodinâmica. Foi estabelecida uma correlação entre as características microestruturais e o comportamento eletroquímico das ligas. Os resultados indicaram que adições de fósforo e alumínio em teores de até 1,0%p têm um efeito benéfico sobre as propriedades magnéticas e resistência à corrosão da liga padrão. A presença de cobre, por outro lado, diminui sensivelmente as propriedades magnéticas da liga padrão.
HDDR process has attracted great interest for producing polymer- bonded rareearth based magnets. It presents commercial advantages when compared with conventional sintered magnets owing to easy and low cost manufacturing. With the development of anisotropic powders using praseodymium, the expectations about this process grow e also the need for studying new compositions and alloy additions. In this work the magnetic properties of polymer-bonded magnets prepared with PrFeB magnetic alloys using HDDR process have been studied. Pr14FebalCo16B6Nb0,1 was used as the reference alloy Phosphorus, copper, aluminium, galium and gadolynium additions have been performed to increase the magnetic properties of the reference alloy. The microstructural characterization of the magnets has been carried out through optical microscopy and SEM. The complex microsctructure influences the electrochemical behavior of the magnetic alloys. The literature about this subject is scarce. Thus, the corrosion resistance of the different alloys prepared during this work was evaluated using electrochemical impedance spectroscopy and potentiodynamic polarization curves. A correlation between the microstructural features and the electrochemical behavior of the alloys has been established. The results showed that phosphorus and aluminium additions up to 1.0wt% had a beneficial effect on the magnetic properties and corrosion resistance of the alloys. Copper additions, on the other hand, strongly diminished the magnetic properties of the reference alloy.

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Merch, Raul Eduardo da Rocha. "Estratégias de cocriação e inovação dirigidas pelo design nas redes ecossistêmicas do Business to Business (B to B): caso Clippertec". Universidade do Vale do Rio dos Sinos, 2016. http://www.repositorio.jesuita.org.br/handle/UNISINOS/5714.

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O ambiente organizacional do Business to Business (B to B) é constituído por uma multiplicidade de empresas e profissionais. Sua operacionalidade acontece por relações interdisciplinares, interfuncionais e interorganizacionais, formando uma grande rede de negócios. Nesse ecossistema corporativo, o designer assume o papel de ator intérprete, projetando cenários, interligando relações e construindo processos e projetos coletivos de estratégias que visam inovação. Como pouco são os estudos sobre o uso de redes ecossistêmicas de intérpretes e processos de colaboração cocriativa que projetem inovações pelo design nesse segmento, o objetivo geral desta pesquisa é identificar se a rede ecossistêmica de intérpretes de uma empresa B to B, pode promover, por meio da colaboração cocriativa, estratégias de design dirigidos à inovação. Para tanto as escolhas da fundamentação teórica, assim como a investigação-ação, abordam uma temática sobre redes, ecossistema, intérpretes, cocriação, inovação, seguido de uma prática de projeto. Com base nesse pressuposto, busca-se responder ao objetivo da pesquisa, utilizando a pesquisa-ação que utilizou como unidade de análise o ecossistema da Clippertec, industria fabricante de equipamentos para o segmento Pet. A metodologia da pesquisa é estruturada por um ciclo de pesquisa-ação. A partir da reflexão teórica, do entendimento de redes, ecossistemas, processos de colaboração cocriativa, inovação, identificação dos segmentos, empresas e profissionais, participantes da rede ecossistêmica da Clippertec, construiu-se um modelo próprio de redes de intérpretes, qual serviu para desenvolver ações projetuais na prática de projeto ocorrida no workshop. A discussão contemplou aspectos relacionados a construção e graus de relações da rede de intérpretes, contribuições por meio de colaboratividade cocritativa, através do workshop e ações projetuais para o desenvolvimento de estratégias de design dirigidos à inovação. Os resultados apontam para a possibilidade de aplicação de um modelo de rede ecossistêmica de intérpretes que, através de colaboração cocriativa, promovam estratégias de design dirigidos à inovação no segmento business to business (B to B).
The organizational environment of Business to Business (B to B) consists of a multiplicity of companies and professionals. Its operability happens for relationships which are increasingly interdisciplinary, cross-functional and inter-organizational, forming a large network of business. In this corporative ecosystem, the designer assumes the role of interpreter actor, projecting scenarios, linking relationships and building processes and collective projects of strategies aimed at innovation. As there are few studies on the use of ecosystem networks of interpreters and co-creative collaborative processes that project innovations by design in this segment, the overall objective of this research is to identify whether the ecosystem network of interpreters of a company B to B, can promote, through co-creative collaboration, design strategies driven toward innovation. Therefore the choices of the theoretical foundation, as well as research-action, address the theme on networks, ecosystem, interpreters, co-creation, innovation, followed by a design practice. On the basis of this presumption, the aim is to respond to the objective of the research, using action-research that utilizes as a unit of analysis the Clippertec ecosystem, industry manufacturer of equipment for the Pet segment. The research methodology is structured by a cycle of action-research from the theoretical reflection, the understanding of networks, ecosystems, co-creative collaboration processes, innovation, identification of segments, companies and professionals, ecosystem network participants from Clippertec, constructed by its own model of networks of interpreters, which served to develop actions in design practice that occurred in the workshop. The discussion contemplated aspects related to construction and degrees of relationships of the interpreters network, contributions from co-creative collaborations, through the workshop and design actions for the development of design strategies driving innovation. The results point to the possibility of applying an ecosystem network model of interpreters which, through co-creative collaboration, promote design strategies driving innovation in the B to B segment.

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Bourgeois, Nathalie. "Suivi de la leishmaniose viscérale méditerranéenne et de la résistance à l'amphotéricine B et aux antimoniés chez les patients infectés par le VIH". Montpellier 1, 2010. http://www.theses.fr/2010MON1TA06.

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La leishmaniose viscérale (LV) est une infection opportuniste chez les patients infectés par le virus de l'immunodéficience humaine (VIH). Malgré le traitement par les antirétroviraux et un traitement de la LV bien conduit, l'évolution vers des récidives est fréquente. La l ere partie de ce travail a consiSté en une étude "bio-clinique" menée sur une cohorte de 27 patients co-infectés Leishmania/VIH suivis au long cours, elle a permis de mettre en évidence des facteurs de risque de survenue de L V, de montrer l'intérêt majeur de la PCR pour le suivi clinique et thérapeutique de cette affection et de définir une forme évolutive de LV particulière à ce type de patients. Le défaut de réponse thérapeutique à l'amphotéricine B chez ces patients nous a conduit à caractériser les isolats de L. Infantum afin de déterminer la nature des épisodes secondaires de LV (ré-infection ou rechute) et à étudier leur chimiosensibilité in vitro. Nous avons donc mis au point et évalué différentes méthodes de test de chimiosensibilité sur promastigotes et amastigotes. La sensibilté à l'amphotéricine B et aux dérivés antimoniés a été évaluée. Enfin, l'ergostérol constituant la cible privilégiée de l'amphotéricine B , nous avons analysé la modification de la composition de la membrane de parasites résistants et sensibles. Ces travaux ont permis de valider trois modèles de test de chimiosensibilité in vitro. L'absence de détection de résistance à l'amphotéricine B des isolats in vitro malgré une non-réponse clinique, le fort taux de résistance aux dérivés antimoniés, ainsdi que les modifications de la composition membranaire en stérols de souches résistantes à l'amphotéricine B sont discutés
Visceral leishmaniasis (VL) is an opportunistic infection in HIV-I-positive patients. Recurrences are frequent despite Highly Active Anti-Retroviral Therapy and adequate antileishmanial treatment. The first part of this work consisted in a 'bioclinical' study of a cohort of 27 Leishmania/HIV co-infected patients which were followed-up in the long term; this allowed (i) highlighting VL risk factors, (ii) showing the major interest of PCR in clinical and drug treatment follow-up of these patients, and (iii) defining a nosological entity of VL specific to this kind of patients. The inefficiency of amphotericin B treatment in these patients then lead us on the ione hand, to characterize Leishmania infantum isolates in order to determine the nature of their secondary episodes of VL (relapse or re-infection), and, on the other hand, to study the in vitro drug sensitivity of the same isolates. Different methods of in vitro drug susceptibility testing were perfected and evaluated using both promastigote and amastigote forms. Sensitivity to amphotericin Band antimonials was evaluated. Finally, ergosterol being the target of amphotericin B, we analyse the modifications in membrane sterol composition of sensitive and resistant parasites. These studies permitted to validate three in vitro drug susceptibility methods. The apparent absence of in vitro resistance to amphotericine B despite an absence of clinical response, the high resistance rate to antimonials and the modifications in membrane sterol composition of amphotericin B resistant strains are discussed

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Parkes, Roberta Leigh. "Part A. Intrazeolite organometallic kinetics, Part B. Ligand effects on the structures of Rh¦6(CO)¦1¦4LL clusters". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ62943.pdf.

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Hammond, Robert Paul. "The structural chemistry of the stuffed tridymites A[BPO¦4] (A = Na, Ag; B= Be, Co, Zn) and A[BCO¦4] (A = Na, K; B= Al, Fe; C = Si, Ge)". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0024/NQ30144.pdf.

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Spengler, Catrina [Verfasser]. "Charakterisierung der funktionellen Relevanz des zellulären Proteins α-Taxilin als potentieller Co-Rezeptor für das Hepatitis-B-Virus / Catrina Spengler". Mainz : Universitätsbibliothek der Johannes Gutenberg-Universität Mainz, 2020. http://d-nb.info/1224895525/34.

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Wang, Ju [Verfasser], Kornelius [Gutachter] Nielsch e Jürgen [Gutachter] Eckert. "Formation, structure and properties of ultrahigh-strength Co-Ta-B bulk metallic glasses / Ju Wang ; Gutachter: Kornelius Nielsch, Jürgen Eckert". Dresden : Technische Universität Dresden, 2021. http://d-nb.info/1232410322/34.

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Roldao, Juan Carlos. "Estrutura eletrônica de derivados de politieno[3,4-b]-tiofeno-co-benzoditiofeno para aplicação em camadas ativas de células solares orgânicas". Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/138182.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Atualmente existe uma intensa busca por novos materiais com propriedades ajustadas para utilização em células solares orgânicas de modo a obter um aumento em sua eficiência de conversão para que possam substituir os dispositivos de silício. O politieno[3,4-b]-tiofeno-co-benzoditiofeno (PTB7) é um polímero recentemente proposto na literatura e com propriedades muito interessantes em células solares orgânicas, o que o coloca como uma possível alternativa ao amplamente utilizado poli(3-hexiltiofeno) (P3HT). Tem sido relatadas modificações em diferentes posições da unidade monomérica deste copolímero, tanto na estrutura benzoditiofeno (BDT), quanto na estrutura tienotiofeno (TT), que o compõe. Estas modificações levaram a novos polímeros com propriedades diferentes e por vezes mais interessantes que aquelas do PTB7 sem substituições. O trabalho que será apresentado visou estudar as propriedades estruturais, eletrônicas e ópticas do PTB7 e possíveis alterações ocorridas devido às modificações químicas realizadas na estrutura do BDT de suas unidades monoméricas. Tal estudo utilizou ferramentas de otimização de estruturas como Mecânica Molecular, Dinâmica Molecular e o método semi-empírico Parametric Method 6 (PM6), assim como de cálculo de estrutura eletrônica de materiais, como a Teoria do Funcional da densidade (DFT) e de cálculos de propriedades ópticas como a Teoria do Funcional da Densidade Dependente do Tempo (TD-DFT). Concluímos que o PTB7 no estado sólido pode ser considerado planar. Com o nosso modelo para o PTB7, obtivemos uma diferença de energia ∆EHL entre o Último Orbital Molecular Ocupado HOMO (do inglês Highest Occupied Molecular Orbital) e o Primeiro Orbital Molecular Desocupado LUMO (do inglês Lowest Unoccupied Molecular Orbital) de aproximadamente 1,84 eV, sendo que este valor está em boa concordância com o valor experimental. Em relação às substituições químicas, estudamos teoricamente 8 derivados do PTB7 e os resultados mostraram que é possível obter compostos com uma diminuição significativa do ∆EHL e também que é possível obter compostos com valores de energia do HOMO e do LUMO mais interessantes que os do PTB7 quando na camada ativa for empregado como material doador o fenil-C61-butírico ácido metil ester (PCBM).
Currently there is an intensive search for new materials with tuned properties for use in organic solar cells to obtain an increase in its conversion efficiency and replace silicon devices. The polythieno[3,4-b]-thiophene-co-benzodithiophene (PTB7) is a polymer recently proposed in the literature and with very interesting properties in organic solar cells, which places it as a possible alternative to the widely used poli(3-hexilthiophene) (P3HT). It has been reported changes in different positions of the monomeric unit of this copolymer, both in benzodithiophene (BDT) structure, as in the thienothiophene (TT) structure that compose it. These modifications led to new polymers with different properties and sometimes more interesting than those of PTB7 without substitutions. The work to be presented aimed to study the structural, electronic and optical properties of PTB7 and possible changes due to chemical changes made in the BDT structure of its monomeric units. This study employed optimization tools like Molecular Mechanics, Molecular Dynamics and Parametric Method 6 (PM6), as well as calculations of the electronic structures with the Density Functional Theory (DFT) method, and optical properties such as the Time Dependent Density Functional Theory (TD-DFT) calculations. We conclude that the PTB7 chains in the solid state can be considered planar. With our model for PTB7, we obtained a difference ΔEHL between the Highest Occupied Molecular Orbital (HOMO) and the Lowest Unoccupied Molecular Orbital (LUMO) of approximately 1.84 eV, and this value is in good agreement with the experimental value. Regarding chemical substitutions, we studied theoretically 8 derivatives of PTB7 and the results showed that it is possible to obtain compounds with a significant decrease in ΔEHL and that it is possible to obtain compounds with HOMO and LUMO energy values more adjusted to the widely employed acceptor material phenylC61-butyric acid methyl ester (PCBM).

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Fallot, Guillaume. "La recombinaison de l'ADN du Virus de l'hépatite B chez des patients co-infectés par le virus de l'immunodéficience humaine". Paris 7, 2011. http://www.theses.fr/2011PA077246.

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L'infection chronique par le virus de l'Hépatite B (VHB) est un problème majeur de santé publique mondiale, avec plus de 350 millions de patients chroniquement infectés qui ont un risque accru de décompensation hépatique, de cirrhose et de carcinome hépatocellulaire. La pathogénèse du VHB est complexe et il semble que les variants moléculaires jouent un rôle dans ce processus. La variabilité de l'ADN VHB pendant le suivi des patients n'a presque pas été étudiée. La recombinaison entre différents génotypes VHB a été décrite dans de nombreuses études transversales, mais la fréquence des recombinaisons inter- et intragénotypiques se produisant chez un patients n'est pas connue. Nous avons étudié 32 patients positifs pour le VIH et 11 patients négatifs, pour lesquels persistait une virémie VHB malgré un traitement antiviral d'au moins un an. Le génotypage a été réalisé par hybridation en milieu liquide (INNO-LiPA) et par PCR spécifique du génotype. La variabilité de l'ADN VHB dans le temps a été examinée par l'étude du polymorphisme conformationnel des simples brins et des longueurs des fragments de restriction (RFLP-SSCP). Les séquences d'ADN VHB obtenues par le clonage d'un fragment PCR de 2800 pb ont été analysées pour les paramètres phylogénétiques (diversité et pression de sélection), et la recombinaison a été détectée par la suite de logiciels RDP. De larges fragments d'ADN VHB ont pu être amplifiés à deux temps différents chez 33 patients. Des modifications marquées de la quasiespèce survenaient chez 14 patients. Un fragment de 2800 pb a été cloné et séquencé à au moins deux temps différents chez 7 de ces patients, et chez un patient ne présentant pas de changement détectable par RFLP¬SSCP. Chez 4 (57%) des patients du groupe de 7, nous avons détecté des recombinaisons inter-ou intragénotypiques variées entre des variants de la quasiespèce initiale. Les fragments recombinants hébergeaient pour la plupart des déterminants de la résistance antivirale et reflétaient une augmentation massive de la diversité et de la pression de sélection positive de la quasiespèce totale VHB. Chez les patients co-infectés, les évènements de recombinaison de l'ADN VHB sont fréquents pendant la thérapie antivirale. Ils correspondent à une augmentation de la pression de sélection positive et à la conservation des mutations de résistance aux antiviraux. Dans cette population et à l'échelle individuelle, la recombinaison est une source significative de variabilité génétique du VHB
Hepatitis B virus (HBV) chronic infection remains a challenging global health problem, with more than 350 million people chronically infected and at risk of hepatic decompensation, cirrhosis, and hepatocellular carcinoma. HBV pathogenesis is complex and it appears that molecular variants play a role in this process. The variability of HBV DNA over times has been scarcely studied. Recombination between different HBV genotypes has been described in many cross-sectional studies, but the frequency of inter- and intra-genotypic recombination in individual patients is unknown. We studied 32 HIV-positive and 11 HIV-negative patients who remained HBV viremic on antiviral therapy for at least one year. Genotyping was based on line-probe assays and genotype specific PCR. The variability of HBV DNA over time was examined with restriction-length and single-strand conformational polymorphism (RFLP-SSCP). HBV DNA sequences obtained by cloning a 2800-bp PCR fragment were analyzed for phylogenetic parameters (diversity and selection pressure), and recombination was detected with RDP softwares. Large fragments of HBV DNA could be amplified at two different time points in 33 patients. Marked quasispecies modifications occurred in 14 patients. In 7 of these latter patients and in one patient with no change detectable by SSCP-RFLP, the 2800-bp fragment was cloned at at least two time points. In 4 (57%) of the former 7 patients, we detected various inter- or intra-genotypic recombination events between subvariants present in the initial quasispecies. Recombinant fragments mostly harbored antiviral resistance determinants and reflected a massive increase in diversity and in positive selection pressure on the entire HBV quasispecies. In coinfected patient, HBV DNA recombination events are frequent during antiviral therapy corresponding to increased positive selection pressure on the HBV quasispecies and to conservation of antiviral resistance mutations. In this population and at the individual level, recombination is a significant source of HBV genetic variability

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