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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Vylučovací žaloba v exekučním řízení / The action to exclude a claim from the enforcement of the judgment

Svoboda, Ondřej January 2013 (has links)
Debarment action in execution proceedings The thesis targets the interpretation of debarment actions in execution proceedings. Generally the thesis provides a definition of debarment actions as a legal institution for the protection of third party rights and of debarment action execution proceedings. On the other hand the thesis is very particular in terms of the specifics of individual forms of debarment actions. The interpretation does presented also refers to current jurisprudence as applied by Czech courts as regards debarment actions, as well as in further related cases. The legal interpretation points out to the possibility of future amendments to certain legal provisions. The first Chapter of the thesis defines fundamental legal terms and institutions, which create a broader base for debarment action interpretations. The thesis focuses on the definition of notions of execution, the status of bailiffs, execution proceedings and the parties thereto as well as the sources of law including the definition of the inter relationship between Civil Procedure Code and Execution Procedure, which are cardinal for the main subject of the thesis. The interpretation contained in Chapter two aims at general description of debarment actions, their subjects and status within incidence disputes and it also...
32

Synthèse de groupements protecteurs photolabiles pro-fluorescents sensibles à l’excitation bi-photonique / Synthesis of two-photon sensitive pro-fluorescent photoremovable protecting groups

Abou Nakad, Elie 16 November 2018 (has links)
Les groupes protecteurs photolabile (GPP) ont été largement utilisés en synthèse organique et pour des applications biologiques. Parmi la grande diversité de ces groupes, les groupement o-nitrobenzyl sont les plus utilisés. En particulier, ils ont été abondamment employés dans la préparation de nombreux précurseurs photolabiles d’effecteurs biologiques. Ce qui permet d’utiliser une réaction photochimique afin de transformer un composé biologiquement inerte en composé actif avec formation d’un sous-produit de photolyse. Afin de pouvoir quantifier le saut de concentration de l’effecteur biologique en particulier sur des cellules, nous avons développé des nouveaux GPP dérivés d’o-nitrobenzyle, qui libère un sous-produit de photolyse présentant des propriétés de fluorescence. Ainsi en nous basant sur le mécanisme de photolyse de dérivés o-nitrobenzyl sensible à l’excitation bi-photonique, nous avons pu concevoir un GPP non-fluorescent qui libère un fluorophore après photoclivage. Les propriétés de fluorescence du sous-produit de photolyse ont également été optimisées. Enfin à l’aide de ces PPG pro-fluorescent nous avons pu valider que la réaction photolytique peut être suivie par microscopie de fluorescence sur des cellules en culture. / Photoremovable Protecting Groups (PPG) have been widely used in organic synthesis and in various biological applications. Among the wide diversity of these groups, o-nitrobenzyl groups are the mostly used chromophores. In particular, they have been extensively used for the design of caged compounds. Those latter type of compounds are able to release a biological effector together with an uncaging side-product leading to the spatiotemporal control of various biological processes. In order to acutely monitor the uncaging event for example in cells, we developed new PPGs, based on o-nitrobenzylderivatives, able to release a fluorescent side product. Based on the photolytical mechanism of two-photon sensitive o-nitrobenzyl PPGs, we were able to design new non-fluorescent PPGs able to release fluorophores as side products. We were also able to tune the fluorescent properties of the photo-released by product using molecular engineering. Finally, those pro-fluorescent PPGs have been used in order to follow the uncaging events by fluorescent microscopy on cell cultures.
33

Studies towards a second-generation synthesis of the aplyronines

Anzicek, Nika January 2017 (has links)
The aplyronines are a family of 24-membered macrolides of polyketide origin, isolated from the Japanese sea hare Aplysia kurodai. They exhibit an exceptional biological activity profile, acting through an actin and tubulin dual-targeting mechanism, with subnanomolar growth inhibitory potency against a diverse range of cancer cell lines. These characteristics render the aplyronines ideal payloads for antibody-drug conjugates but their prohibitively low natural abundance calls for an efficient total synthesis to overcome the supply issue. This dissertation describes the efforts towards developing a second-generation Paterson synthesis of the macrocyclic core of the aplyronines, focused on improving the scalability and selectivity of key transformations. Chapter 1 details the isolation, biological background and previous synthetic efforts towards the aplyronines to illustrate their therapeutic potential and the challenges associated with material sourcing by chemical synthesis. Chapter 2 presents the existing body of work on the aplyronine project within the Paterson group, highlighting the lessons learned over the past two decades and shortcomings to be addressed. Chapter 3 discusses a revised protecting group strategy towards the C1-C27 macrocyclic alcohol 159 with fewer manipulation steps. A refined reaction sequence featuring titanium aldol methodology and an enzymatic desymmetrisation process delivered multigram stocks of the C15-C27 aldehyde 161 upon scale- up, testifying to the robustness of the devised route. Synthesis of the C1-C14 northern fragment 253 closely followed the existing boron aldol approach with optimisation of the C11-C12 alkylation step, geared towards enhancing the regioselectivity. Chapter 4 describes the coupling of the two major fragments using an Horner-Wadsworth-Emmons reaction to assemble the C1-C27 backbone of the cyclic aplyronine core and suitably adjusted endgame steps to enable a one-step oxidative unmasking of the macrolactonisation sites. The first-generation intermediate 159 was accessed via site-specific Yamaguchi esterification and orthogonal deprotection of the C27 allyl carbonate. Discussion in Chapter 5 includes the appendage of the C28-C34 side chain 118, prepared by the known sequence, and suggestions for the future direction of the second-generation route with the outlook of linker appendage for the purposes of antibody-drug conjugate development.
34

Organic Heavy Group 14 Element Compounds : A Study of Their Chemical Bonding Properties Directed Towards Applications as Molecular Wires and in Synthesis

Tibbelin, Julius January 2010 (has links)
The research described herein includes synthesis, spectroscopy, and quantum chemical calculations with focus on the characteristic properties of compounds with bonds between carbon and the heavier Group 14 elements. The chapters based on the first four papers concern σ- and σ/π-conjugated compounds, although the focus of the first paper is on ring strain of bicyclo[1.1.1]pentanes with C, Si, Ge or Sn at the bridgeheads. The relationship between calculated homodesmotic ring strain energies and through-space distances between the bridgehead atoms was evaluated, and it was found that replacing one of the methylene bridges with phospha-methyl gave both low strain and short through-space distance. Two kinds of σ/π-interacting systems were analysed with the difference that the σ- and π-bonded segments were either allowed to rotate freely relative each other or frozen into a conformer with maximal σ/π-interaction. The freely rotating systems are star-shaped oligothiophenes linked by heavy alkane segments. Density functional theory (DFT) calculations of hole reorganization energies support the measured hole mobilites. In summary, longer central oligosilane linkages, when compared to shorter, facilitate intermolecular hole-transfer between oligothiophene units. In 1,4-disilacyclohexa-2,5-dienes, the strength of the π- and pseudo-π interaction depends on the substituents at Si. Vapour phase UV absorption spectroscopy of 2,3,5,6-tetraethyl-1,1,4,4-tetrakis(trimethylsilyl)-1,4-disilacyclohexa-2,5-diene reveals a strong absorption at 273 nm (4.50 eV). Time-dependent DFT calculations further indicate that octastannylated 1,4-disilacyclohexa-2,5-diene has is lowest excited state at 384 nm (3.23 eV). The electronic, geometric and optical properties of substituted 1,4-disilacyclohexa-2,5-dienes were compared with those of the correspondingly substituted siloles. It was found that the lowest excitations of siloles are less tunable than those of 1,4-disilacyclohexa-2,5-dienes. The final section concerns strongly reverse-polarised 2-amino-2-siloxysilenes formed thermally from carbamylpolysilanes, and their lack of reaction with alcohols. Instead, the carbamylsilane reacts with alcohols giving silyl ethers, leading to a new benign route for alcohol protection.
35

Studies in failure independent path-protecting p-cycle network design

Baloukov, Dimitri Unknown Date
No description available.
36

Studies in failure independent path-protecting p-cycle network design

Baloukov, Dimitri 11 1900 (has links)
Failure Independent Path-Protecting (FIPP) p-Cycles is a recently proposed protection architecture for transport networks that extends the properties of mesh-like efficiency and ring-like speed of span-protecting p-cycles to path protection. FIPP pcycles provide shared end-to-end protection to working paths and exhibit properties of pre-connection, end-node activation and failure independence. In his thesis we advance the state of the art in FIPP p-cycle networking. We first introduce two new methods for FIPP p-cycle network design: FIPP column generation (CG) and FIPP iterative heuristic (IH). This is followed by the introduction of a new method for joint capacity placement design called FIPP disjoint route set (DRS) joint capacity placement (JCP) which is followed by an in-depth investigation on the effects of jointness in FIPP p-cycle designs. Next we introduce a series of comparative case studies involving several pre-connected network survivability architectures in the context of transparent optical networking. These studies include topics of single, dual and node failure restorability, minimum wavelength assignment and transparent reach analysis. The final contribution of this thesis is the investigation of the capital expenditure associated with the implementation of FIPP p-cycle designs using optical transport networking equipment as described in the NOBEL cost model. A new method called FIPP maximize unit path straddlers (MUPS) is introduced as part of this final study in order to utilize the property of same wavelength protection. This new approach is motivated by opportunities for cost reduction discovered in the initial costing exercise of the NOBEL cost model investigation.
37

Protecting DAISY content

Hinderer, Sebastian, Burger, Dominique, Marmol, Bruno 12 July 2011 (has links) (PDF)
DAISY has published a Specification for DAISY Protected Digital Talking Book. This paper discusses why such a specification is useful, not only for rightsholders but also for readers with print disabilities. An implementation of PDTB2 is proposed, called dtbprotect. It makes possible to simply produce an encrypted book from a book in DAISY format. It is currently experimented on the Helene Digital Library for the blind. It will be made available open source as to facilitate its implementation by other digital libraries.
38

Strategizing and Managing coopetition : Sharing, protecting and/or capturing knowledge / Les stratégies de coopétition et leur management : partager, protéger et/ou capturer des connaissances

Bez, Sea Matilda 22 November 2017 (has links)
Cette thèse explore la question suivante : comment les entreprises gèrent-elles la coopétition par le prisme du partage de connaissances ? et à quelles intentions stratégiques répondent ces choix managériaux ? Notre principal résultat consiste en l’identification de trois stratégies de coopétition, chacune reposant sur un management particulier du partage de connaissances. Les deux premières s’inscrivent dans la continuité des travaux existants sur la coopétition. Elles adoptent une approche Hamelienne de course à l’apprentissage, dans laquelle la gestion du partage consiste à trouver des techniques pour partager la connaissance critique pour le succès du projet commun, sans permettre au partenaire d’internaliser la connaissance. Ces techniques consistent à « protéger » ou « partager & protéger ». En revanche, la troisième stratégie identifiée, à l’inverse des prédictions de la littérature sur la coopétition, encourage un partage plus ouvert et intensif qui peut même aller jusqu’à renforcer le coopétiteur avec sa connaissance. Mais si l’entreprise s’engage dans cette stratégie ce n’est pas par altruisme ou par volonté d’aider l’autre, mais parce qu’elle perçoit une opportunité pour capturer de nouvelles connaissances. Ainsi, les entreprises ont conscience de la dynamique positive de création de connaissances qui va être générée en partageant de manière transparente au lieu de réduire la transparence (i.e., processus de capture de valeur constructif). Cette troisième stratégie permet d’aller plus loin dans notre compréhension des stratégies de coopétition et de leur management. Elle ouvre la voie à de nouvelles recherches se basant sur des fondements intégrant Deutsch et Nonaka. Notre contribution n’est pas uniquement académique, elle est aussi managériale. Elle ouvre les champs des possibilités d’actions des dirigeants, en identifiant une stratégie contre-intuitive, pour maximiser les opportunités liées à une relation de coopétition. De plus, notre modèle intégrateur peut être réutilisé pour former les individus à la coopétition en leur permettant d’identifier trois stratégies et leurs implications organisationnelles. / We investigate how does a focal firm strategize and manage coopetition through the specific lens of knowledge sharing. Based on two case studies of two firms considered as masters in the management of coopetition, we identify three ways to create and pursue the focal firm’s current and future advantage in coopetitive project. The two first ways confirm the dominant research approach of coopetition which argues that a focal firm should obstruct or reduce to its strict minimum the coopetitor’s potential for internalizing the knowledge shared for the project success (i.e. reduce or restrict the focal firm’s knowledge transparency). Indeed, the value creation of a coopetitive project success can be jeopardized by the fear of knowledge sharing between competitors. The reduction or restriction of its knowledge transparency is a key organizational solution to overcome this fear of knowledge sharing and thus this fear of collaborating with a competitor. Alternatively, we identified a third way of strategizing and managing coopetition which goes one step further in coopetition. Indeed, by building on our empirical results, Deutsch’s theory of conflict resolution and Nonaka’s organizational knowledge creation theory, we argue that the creation and pursuit of current and future advantage for a focal firm in coopetitive project can also consist in implementing a strategy and management based on greater and freer transparency. In that case, the dominant coopetitive knowledge sharing adages of “protecting” or even “sharing and protecting” shift into “sharing and enabling for constructive capturing.” This third way opens academic research opportunities based our boarder theoretical roots than Hamel’s approach of inter-firm relationships in which the strategic intent is a learning race and one of the key organizational element is a minimized transparency. It also has managerial contributions. Indeed, it increases top management analytical capability by generating a new counter-intuitive insight: enabling a competitor in a coopetitive project can be strategic tool to create and pursue current and future advantage for themselves. Moreover, our integrated framework can be reused to train the analytical coopetitive capabilities of top managers by making them aware about three ways of strategizing and managing coopetition.
39

Nanostructuration de groupements protecteurs photolabiles sensibles à l'excitation bi-photonique pour les neurosciences / Two-photon sensitive photolabile protecting groups : from molecular engineering to nano-structuration

Piant, Sébastien 23 November 2015 (has links)
Les groupements protecteurs photolabiles sont utilisés pour de nombreuses applications, notamment en neuroscience pour la libération de neurotransmetteurs avec un contrôle spatio-temporel très fin. La démocratisation des lasers pulsés infrarouges a permis la mise au point de nouveaux composés sensibles à l’excitation à deux photons, de plus en plus efficace. Cependant, l’ingénierie moléculaire des cages n’est pas la seule méthode qui peut être utilisée pour améliorer l’efficacité des de ces composés. Mon travail de thèse a ainsi abordé cette problématique sous l’angle de la nanostructuration de groupements protecteurs photolabiles sensibles à l’excitation à deux photons. Nous avons débuté cette étude avec des composés de petite taille (dimère et tétramère) basés sur des groupements photosensible type ortho-nitrophénéthyle. Nous avons ensuite fonctionnalisé des dendrimères de type polyamidoamine, cependant les propriétés photophysiques et photochimiques de ces nouveaux composés suggèrent que des interactions intramoléculaires perturbent l’efficacité de la réaction de photolibération. Des dendrimères partiellement fonctionnalisés ont ensuite été envisagés. / Photosensitive protecting groups have been used for many applications, including neuroscience for the release of neurotransmitters with an amazing spatio-temporal control. New compounds sensitive to two-photon excitation were developed with the spread out of pulsed infrared lasers. However, cages molecular engineering is not the only way to improve such compounds. This manuscript focuses on nanostructuration to improve the overall efficiency of two-photon sensitive protecting groups. We started our study with small compound as dimer and tetramer based on the ortho-nitrophenethyl architecture. Next, polyamidoamine dendrimers were tested, but photophysics and photochemistry properties of these new compounds suggest that intramolecular interactions disturb photochemical reaction. Synthesis of partially functionalized dendrimer was considering in a next step.
40

Illuminating Biology with Membrane Penetrating Sulfonate Delivery Scaffolds and Near-Infrared Azasiline Fluorophores

Choi, Adam 07 September 2018 (has links)
Near-infrared (NIR) light, with wavelengths of 650 to 900 nanometers, effectively penetrates tissues. The high signal to noise ratio and low phototoxicity of NIR light makes this wavelength range ideal for deep tissue imaging. However, current NIR fluorophores are generally large hydrophobic molecules that are prone to aggregation. Sulfonation can enhance aqueous solubility, but their anionic nature prevents membrane diffusion, and thus, restricts the applications of sulfonated molecules to in vitro or fixed cells. The repertoire of commercially available sulfonated NIR probes is mostly limited cyanines, which have low photostability. Moreover, larger cyanines require multiple sulfonates to maintain aqueous solubility. For example, Indocyanine Green is only sparingly soluble in PBS, despite having two sulfonates. My work has focused on the delivery of sulfonated dyes into live cells and the development of a new, ultra-compact NIR dye scaffold. First, to expand the in-cell applications of sulfonated fluorophores, I designed reductively-labile sulfonate protecting groups. Using these scaffolds, I have successfully delivered the fluorophore dansyl sulfonate into live cells, where the cytosolic reducing environment unmasks the anionic sulfonate. Secondly, to create a compact, photostable NIR fluorophore, I pioneered the discovery of azasilines dyes. The two azasiline derivatives, ASiFluor710 and ASiFluor730, fluoresce over 700 nanometers and are among the most compact NIR fluorophores currently known. ASiFluor730 also retains the high photostability of oxazine dyes, highlighting their potential in long exposure applications. Beyond the immediate applications in fluorescence microscopy and in vivo imaging, I envision that my work will serve as a framework for the future design of soluble, membrane permeable, NIR fluorescent probes.

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