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Les complexes Ni-bis (dithiolène) pour des applications en science des matériaux et en biotechnologies / Ni-bis(dithiolene) complexes for application in science materials and biotecnologiesMebrouk, Kenny 11 October 2016 (has links)
Ce travail démontre l'utilité des propriétés photothermiques dans le proche Infrarouge (NIR) des complexes de nickel-bis(dithiolène) neutres pour des applications en science des matériaux et biotechnologies. Des complexes Ni-bis(dithiolène) neutres hydrophiles et hydrophobes ont été élaborés et leur effet photothermique, sous irradiation laser NIR, a été quantifié pour la première fois. Grâce à cette propriété remarquable et à leur grande stabilité sous irradiation, il a été mis en évidence, que ces complexes pouvaient trouver des applications pour la thérapie photothermique, la libération contrôlée de médicament mais également pour le développement de nanomatériaux photosensibles à un stimulus externe. En effet, cet effet photothermique, sous irradiation laser NIR, permet de détruire des cellules cancéreuses, d'augmenter la perméabilité de nanoparticules polymériques ou de liposomes contenant des principes actifs et de désagréger des métallogels à base de complexes Ni-bis(dithiolène). Enfin, nous avons montré que les complexes [Ni(R2-timdt)2]0 ayant une haute efficacité photothermique sont de nouveaux candidats très prometteurs pour ce type d'applications. / The photothermal properties in the near Infrared (NIR) of neutral nickel-bis(dithiolene) complexes were used in materials science and for the first time in biotechnology. Hydrophilic and hydrophobic neutral Ni-bis(dithiolene) complexes were developped and for the first time, their photothermal effect under NIR laser irradiation was quantified. Thanks to this remarkable property and their high stability under irradiaton, it has been demonstrated that these complexes could find applications to photothermal therapy, controlled drug delivery but also in the developpement of stimuli responsive nanomaterials. Indeed, this photothermal effect, under NIR laser irradiation, allow to destroy malignant cells, increase the permeability of polymeric nanoparticles or liposomes containing active ingredients and disintegrate métallogels based on Ni-bis(dithiolene) cores. Finally, we showed that the [Ni(R2-timdt)2]0 complexes having higher phothothermal activity are very promising new candidates for these applications.
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Desenvolvimento, caracterização e avaliação de um sistema osmótico do tipo bicamada / Development, characterization and evaluation of a bilayer osmotic release systemFreitas, Miller Nunes de 23 January 2009 (has links)
Os comprimidos osmóticos do tipo bicamada ou \"push pull\" são sistemas reservatórios constituídos de um núcleo bicamada, circundado por uma membrana semipermeável e com um orifício de liberação perfurado a laser que permitem a liberação do fármaco através da cinética de ordem zero. Este sistema possui a vantagem de apresentar uma liberação controlada e não influenciada pelos fatores fisiológicos do trato gastrointestinal, permitindo aplicações terapêuticas para novos fármacos e inclusive para fármacos já existentes. O presente projeto contemplou as etapas de desenvolvimento, caracterização e avaliação de um sistema osmótico do tipo bicamada ou \"push pull\", para veiculação do atenolol, um beta bloquador de grande importância na terapia antihipertensiva. Após a padronização e validação da metodologia analítica, estudos de compatibilidade entre o fármaco e os excipientes através da análise calorimétrica e espectroscopia no infravermelho (pré-formulação), a produção, a caracterização da membrana de revestimento e, por fim, a avaliação do desempenho dos núcleos osmóticos foram realizados. Assim, três lotes, com 4kg cada, foram produzidos para determinação do peso médio e do ferramental adequados, além da proporção entre os excipientes da formulação. O processo de compressão deu origem aos núcleos osmóticos do tipo bicamada que foram submetidos à avaliação físico-química como determinação do peso médio, da dureza, da friabilidade e da espessura. Além disso, padronizou-se o processo de revestimento dos núcleos com membrana semipermeável e avaliou-se o perfil de captação de água dos núcleos resultantes (\"Swelling\"). A membrana de revestimento foi submetida à microscopia eletrônica de varredura (MEV), análise por adsorção de nitrogênio e porosimetria de mercúrio para verificação da distribuição e tamanho médio dos poros. Para a obtenção do orifício de liberação padronizou-se a quantidade de radiação a laser suficiente para perfuração da membrana semipermeável que envolve os núcleos. Após a perfuração a laser, os núcleos foram submetidos então ao estudo de liberação in vitro para avaliação da influência do diâmetro de orifícios, do número de orifícios, da espessura da membrana semipermeável, da hidrodinâmica do meio de dissolução e da influência térmica na velocidade de liberação do fármaco. A cinética do tipo ordem zero e o controle da liberação do fármaco ao longo do tempo foram alcançados com sucesso a partir dos núcleos osmóticos produzidos no lote 03. / The push pull osmotic release tablets are bilayer core reservoir systems surrounded by semi permeable membrane and with one delivery hole where the drug is released through, following zero order release kinetics. This system has many advantages and two of them are the controlled drug release and independence of physiologically factors allowing many therapeutic applications to new one and known one drugs. This exclusive work proposed the development, characterization and evaluation of atenolol push pull osmotic system that is very important to antihypertensive treatment. After analytical standardization and validation activities, the pre-formulation studies using calorimetric and infra red spectroscopy techniques, manufacturing, semi permeable membrane characterization and finally osmotic tablets performance evaluation were performed. Batches about 4 kg each one were manufactured and tablets average weight, by-layer proportionality and suitable punches were chosen. Thus the osmotic tablets obtained by bi-layer press were physical and chemical evaluated (average weight, hardness, friability, and thickness). After that the tablets were submitted to a coating process with semi permeable membrane and the uptake water profile (Swelling) was observed to characterize the membrane permeability. The semi permeable membrane was submitted also to scanning electron microscopy (SEM), nitrogen adsorption and mercury porosimetry techniques in order to characterize the porous average diameter and distribution. To produce the delivery hole in the drug layer semi permeable membrane the sufficient laser radiation amount was studied and determined. So the perforated osmotic tablets were submitted to in vitro drug release studies to evaluate the influence of hole diameter, hole number, coating thickness, medium hydrodynamic and temperature stress responsible for drug release modifications. Finally the controlled delivery and the zero order drug release kinetics were achieved successfully from osmotic tablets developed and produced in the third bath. This third bath was the result of the factors comprehension and the optimization of the early ones.
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The Predictive Power of CEO Equity Incentive Compensation on the Enforcement of an SEC Accounting and Auditing Enforcement ReleaseHouy, Alexander 01 January 2019 (has links)
This study examines the predictive power of restricted stock and stock option compensation on the enforcement of an Accounting and Auditing Enforcement Release. Since executives have seen substantial increases in the amount of equity incentive awards, this may incentivize management to commit financial reporting misconduct to boost the value of these awards. The magnitude of the incentive to commit financial reporting misconduct is hypothesized to be more pronounced with stock option compensation when compared with restricted stock compensation. The analysis for the 1992-2012 time period shows that the amount of stock option compensation has a positive relationship with the probability of an AAER enforcement while no such relationship exists for restricted stock. When examining this predictive probability relationship during 1992-2002 and 2003-2012, the evidence is mixed. While the amount of stock option compensation displays a positive relationship with the predicted probability of an AAER enforcement, restricted stock has a positive relationship in 1992-2002 and a negative relationship in 2003-2012.
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Analysis of Bimetallic Adhesion and Interfacial Toughness of Kinetic Metallization CoatingsGuraydin, Alec D 01 May 2013 (has links)
Due to their ability to confer enhanced surface properties without compromising the properties of the substrate, coatings have become ubiquitous in heavy industrial applications for corrosion, wear, and thermal protection, among others. Kinetic Metallization (KM), a solid-state impact consolidation and coating process, is well-suited for depositing industrial coatings due to its versatility, low substrate heat input, and low cost. The ability of KM coatings to adhere to the substrate is determined by the quality of the interface. The purpose of this study is to develop a model to predict the interfacial quality of KM coatings using known coating and substrate properties. Of the various contributions to adhesion of KM coatings, research suggests that the thermodynamic Work of Adhesion (WAD) is the most fundamental. It is useful to define interfacial quality in terms of the critical strain energy release rate (GC) at which coating delamination occurs. Studies show that GC for a given interface is related to WAD. This study attempts to develop a theoretical model for calculating WAD and understand the relationship between GC and WAD. For a bimetallic interface between two transition metals, WAD can be theoretically calculated using known electronic and physical properties of each metal: the molar volume, V, the surface energy, γ, and the enthalpy of alloy formation, ΔHinterface; ΔHinterface is a function of the molar volume, V, the work function, φ, and the electron density at the boundary of the Wigner-Seitz cell, nWS.WAD for Ni-Cu and Ni-Ti interfaces were 3.51 J/m2 and 4.55 J/m2, respectively. A modified Four-point bend testing technique was used to experimentally measure GC for Ni-Cu and Ni-Ti specimens produced by KM. These tests yielded mean GC values of 50.92 J/m2 and 132.68 J/m2 for Ni-Cu and Ni-Ti specimens, respectively. Plastic deformation and surface roughness are likely the main reasons for the large discrepancy between GC and WAD. At the 95% confidence level, the mean GC of the Ni-Ti interface is significantly higher than that of the Ni-Cu interface. Further testing is recommended to better understand the relationship between WAD and GC.
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Požadavky vybraných českých médií na mediální vztahy sportovních organizací / Requirements of Selected Czech Media on Media Relations of Sports OrganisationsSlobodníková, Aneta January 2019 (has links)
Title: Requirements of Selected Czech Media for Media Relations of Sports Organisations Objectives: The objective of this thesis is to synthesize sports media's opinions on media relations of sports organizations in Czech republic. The aim is to create a document that will have the potential to improve communication between media and Czech sports organizations. Methods: The qualitative method of interviews was used for data collection, alongside with a guideline based on theoretical framework. Respondents were selected by targeted sampling employing criteria. Interviews were recorded and subsequently transcribed into written form. Obtained data were processed by the deductive method of thematic analysis. Results: The result of this thesis is a summary of requests from media representatives. The results reflect the theoretical framework with practical comments for the Czech sports environment. Overall, media representatives focus on trust from sports organizations and their representatives. They recall that a media output is also a part of a sports career of athletes. They wish to be seen as someone who is a partner in spreading information to the public and fans, not as an enemy. Keywords: public relations, communication, press release, press conference, sports media, media guide, media room,...
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Développement de supports absorbants à base de cyclodextrines pour la désodorisation des atmosphères de travail par des essences naturelles / Development of absorbent substrates based on cyclodextrins for the deodorization of working atmospheres by natural essencesCiobanu, Anca 15 December 2011 (has links)
L’objectif de cette thèse était de réaliser des désodorisants, obtenus à partir de différentes essences naturelles. Ceux-ci doivent être efficaces dans l’amélioration du microclimat des atmosphères de travail. Une étude fondamentale sur l'optimisation de l'extraction des essences naturelles et l'identification des composants de ces essences a été réalisée par GC/MS. Nous avons étudié également les processus de reconnaissance moléculaire entre les composants majoritaires de ces essences et des CDs natives ou modifiées. La stabilité de ces complexes a été mesurée par trois méthodes différentes : l’headspace statique, la spectrophotométrie UV-visible et la microcalorimétrie de titration isotherme. La réalisation d’adsorbants à base de cyclodextrines a été effectuée en utilisant des polymères de cyclodextrine synthétisés à partir de l’épichlorhydrine ainsi que des matériaux hybrides de type CM-β-CD/LDH. L’efficacité des désodorisants obtenus a été évaluée en mesurant la durée de libération des composés odorants. / The objective of this thesis was to develop air fresheners from various natural essences. Those must be efficient in the improvement of working atmosphere microclimate. A fundamental study on the optimization of extraction of natural essences andidentification of components of these essences was performed by GC/MS. We have also studied the process of molecular recognition between the major components of these essences and native or modified CDs. The stability of these complexes was measured by three different methods: static headspace, UV-visible spectrophotometry and isothermal titration microcalorimetry.The realization of adsorbents supports based on cyclodextrins was carried out by using cyclodextrin polymers synthesized from epichlorohydrin and hybrid materials of CM-β-CD/LDH type. The efficiency of air fresheners was evaluated by measuring the release time of odorous compounds.
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Conception, caractérisation et évaluation in vivo d'un vaccin nanoparticulaire anti-VIH et optimisation de sa biodisponibilité par un hydrogel thermosensible / Design, characterization and in vivo evaluation of an anti-HIV nanoparticle vaccine and optimization of its bioavailability by a thermosensitive hydrogelPhelip, Capucine 11 December 2018 (has links)
Les connaissances actuelles indiquent la nécessité d’induire une réponse immunitaire à large spectre et notamment des anticorps multifonctionnels pour protéger de l’infection par le VIH. Les approches vaccinales traditionnelles n’étant pas capables d’induire d’anticorps neutralisants à large spectre (bNAbs) suffisamment puissants contre le VIH-1, des stratégies alternatives sont étudiées afin d’induire ces bnAbs. Les avancées majeures concernent le développement de (i) glycoprotéines d’enveloppe optimisées comme immunogène, (ii) vecteurs transportant et présentant l’immunogène de manière efficace et (iii) la forme galénique permettant d’augmenter la durabilité de la réponse protectrice. Dans ce contexte, l’objectif de ce doctorat est d’évaluer les réponses immunitaires induites par des nanoparticules biodégradables fonctionnalisées avec des glycoprotéines d’enveloppe du VIH et d’optimiser la libération prolongée in vivo de l’immunogène. Dans un premier temps, nous avons comparé plusieurs glycoprotéines et sélectionné une glycoprotéine d’isolat primaire optimisée (SOSIP BG505) pour ses capacités à s’adsorber de manière stable à la surface des nanoparticules biodégradables, tout en exposant les épitopes de neutralisation, et capable d’induire in vivo une réponse immunitaire systémique. Nous avons ensuite conçu un hydrogel thermosensible à base de poloxamers capable d’incorporer ces nanoparticules tout en gardant leur stabilité colloïdale et analysé leur biodistribution par imagerie corps entier chez la souris. L’injection par voie sous cutanée de cet hydrogel permet d’induire une réponse immunitaire humorale forte, stable et des IgGs de forte affinité. Cette nouvelle formulation, innovante et simple à mettre en place, apparait comme une nouvelle stratégie de vaccination applicable à de nombreuses pathologies virales nécessitant l’induction d’anticorps neutralisant de forte affinité et à large spectre / Current knowledge indicates the need to induce a broad-spectrum immune response including multifunctional antibodies to protect against HIV infection. As traditional vaccine approaches are not capable of inducing potent broad-spectrum neutralizing antibodies (bNAbs) against HIV-1, alternative strategies are being investigated to induce these bnAbs. Major advances include the development of (i) optimized envelope glycoproteins as immunogens, (ii) efficiently carrying and immunogenic carriers, and (iii) the dosage form that would increase the durability of the protective response. In this context, the objective of this PhD is to evaluate the immune responses induced by biodegradable nanoparticles functionalized with HIV envelope glycoproteins and to optimize the in vivo sustained release of the immunogen.First, we compared several glycoproteins and selected an optimized primary isolate glycoprotein (SOSIP BG505) for its ability to be adsorbed to the surface of biodegradable nanoparticles, while exposing neutralization epitopes, and capable of inducing a systemic immune response in vivo. We then designed a thermosensitive, poloxamers-based hydrogel, capable of incorporating these nanoparticles while maintaining their colloidal stability and we have analyzed their biodistribution by whole-body imaging in mice. The subcutaneous injection of this hydrogel makes it possible to induce a strong, stable humoral immune response with high affinity IgGs. This new formulation, innovative and easy to implement, appears as a new vaccination strategy applicable to many viral diseases requiring the induction of high affinity neutralizing antibodies and broad spectrum
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Flux associations and their relationship to the underlying heterogeneous surface characteristicsBrown Mitic, Constance Maria. January 1999 (has links)
No description available.
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都市空間結構與公共支出關係之研究 / Urban Spatial Structure and Public Expenditures潘依茹, Pan, Yi Ju Unknown Date (has links)
人口在空間上分布的差異形成集中發展抑或分散發展型態,相對地對於地方財政的支出亦有不同程度的影響。在現今台灣省各地方政府普遍存在著財源短絀之情形下,農地釋出政策的實施所造成都市規模的擴張,是否會引發地方財政加重的趨勢,實有深究的必要。因此本研究的目的,乃在於探討都市空間結構的差異對公共支出的變化影響效果,並進一步提出土地發展政策涵義。
針對上述,本研究擬藉由人口密度斜率此變數,作為都市空間結構之指標,進而瞭解都市發展型態之差異對地方公共支出的影響。所謂人口密度斜率乃是隨著距離的增加,人口在空間上的變化情形。其次,以中位數投票模型理論及官僚模型理論為基礎,建立模型並進行測試,同時為因應農地釋出政策的實施,在台灣省各市鄉鎮都市計畫區農業區釋出的假設前題下,進行模擬分析。
經本研究結果發現,就總體而言,台灣省各市鄉鎮目前之都市空間結構有分散發展的趨勢,並有無效率的現象;次就農地釋出而言,在不考慮人口規模聚集經濟的情況下,過多的土地開發,將會有惡化現存地方財政不足之趨勢。 / The difference of population spreads in the spatial will result in the pattern of concentrated development or dispersed development. Oppo-sitely, the difference pattern will influence to local public expenditures. On the condition that the local government often exists short tag of finance in Taiwan, so to practice policy of agriculture land release which should result in the extension of urban scale whether will increase the final burden or not, has necessary to discuss. Thus, the propose of this study is to discuss that the difference of urban spatial structure has what effect of change influence to pubhc expenditure, and father want to propose the meaning of land development policy.
As above that, this study uses the population density gradient to be the guide of urban spatial structure, and then want to understand the difference of urban development pattern has what influence to local public ex-penditure. Population density describes how rapidly the density falls off with distance. Next, based on the median voter theory and bureaucracy theory to built the model and test it, then for to practice the policy of agriculture land release, this study on the assumption that all agriculture area of urban planned area will be released in Taiwan progresses simulation and analysis which wants to know the influence of agriculture land release.
According to the result of this study, we find, fister, the present con-dition of local public in Taiwan, urban spatial structure has the tend of dis-persed development, and cause to nonefficiency. Second, if the agriculture land release do not consider the agglomeration economics of population scale, then to development too many lands will worse present local final.
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Le gas release comme facteur d'incitation à la concurrence dans l'industrie gazière européenneClastres, Cédric 14 October 2005 (has links) (PDF)
Les caractéristiques de l'offre de gaz en Europe et les spécificités du marché gazier ont conduit les régulateurs à adopter des régulations asymétriques, prenant la forme de gas release et d'objectifs de pertes de parts de marché. Les expériences empiriques montrent, en accord avec la théorie économique, que ces mesures rendent des concurrents actifs sur le marché et ne découragent pas les investissements. En terme de concurrence, les effets sont plus mitigés. Certains effets positifs trouvent certainement leur cause dans la croissance de la consommation qui est parfois exponentielle ou le développement des infrastructures d'importation et de transport. Ces mesures peuvent cependant favoriser les comportements collusifs, les stratégies d'écrémage ou de « reverse cherry picking », ainsi que des entrées inefficaces, rendues possibles car le concurrent est protégé pour une période de temps donnée. Un gas release crée une relation commerciale entre l'opérateur historique et son concurrent, ainsi qu'un système de contraintes sur les capacités de chacun. Les stratégies de prix ou de quantités sont alors modifiées. Les prix d'équilibre sont plus volatils et peuvent s'éloigner nettement du « mark-u p » de concurrence. De même, les stratégies d'un modèle de COURNOT se complexifient. L'opérateur historique, si les quantités rétrocédées sont fortes et ses approvisionnements faibles, peut laisser augmenter volontairement ses coûts pour accroître ses profits. Cette stratégie d'augmentation des coûts des rivaux est d'autant plus possible que le prix de rétrocession est proche de ses coûts d'approvisionnement. Elle ne détériore pas le surplus des consommateurs mais diminue le bien-être. Le régulateur peut restaurer l'incitation à l'efficacité en fixant une proportion rétrocédée en fonction du niveau des approvisionnements observé. Cette proportion ne doit pas être trop faible pour faire bénéficier le marché de l'incitation à l'efficacité de l'opérateur historique et des ventes plus importantes des deux opérateurs. Dans un même temps, une proportion trop élevée accentue les possibilités d'augmentation des coûts des rivaux ou de collusion.
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