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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.
681

Studies on Photocytotoxic Ferrocenyl Conjugates

Babu, Balaji January 2014 (has links) (PDF)
The present thesis deals with different aspects of the chemistry and photo-biology of various ferrocene-conjugates, their interaction with double helical DNA, DNA photocleavage and photo-enhanced cytotoxicity in visible light, localization and cellular uptake to study the mechanism of cell death. Phenyl analogues of the active complexes have been synthesized and used for comparison in biological assays. Chapter I presents an overview of cancer and its types, various treatments for cancer. A general overview on the Photodynamic Therapy, a new modality of light activated cancer treatment and its various possible mechanism of action, has been made. The promise of photoactivated chemotherapy is discussed with recently developed metal based antitumor agents. Biological applications of few ferrocene conjugates as anticancer and anti-malarial agents are discussed. The objective of the present investigation is also presented in this chapter. Chapter II presents the synthesis, characterization, structure, DNA binding, DNA photocleavage, photocytotoxicity and cellular localization of ferrocene-conjugated dipicolylamine oxovanadium(IV) complexes of curcumin. To explore the role of the ferrocenyl moiety the phenyl analogue of the ferrocenyl complexes is synthesized and used as a control for comparison purpose. Chapter III deals with the photo-induced DNA cleavage and photo-enhanced cytotoxicity of ferrocene-conjugated oxovanadium(IV) complexes of heterocyclic bases. The synthesis, characterization, structural comparisons, DNA binding, DNA photocleavage and photocytotoxic activity in visible light are discussed in detail. Chapter IV describes the synthesis, characterization and structure of ferrocene-conjugated oxovanadium(IV) complexes of acetylacetonate derivatives. The complexes are evaluated for DNA binding, DNA photocleavage and photocytotoxic activity in HeLa, MCF-7, 3T3 cells in visible light. The fluorescent nature of the complexes is used to study the cellular localization of the complexes and the mechanism of cell death induced by the complexes is also discussed. Chapter V presents the photocytotoxic effect of ferrocene-conjugated oxovanadium(IV) complexes of different curcuminoids in HeLa , HepG2 and 3T3 cells. Curcumin based fluorescence has been successfully used to study the cellular uptake and localization behavior of the complexes. The positive role of the ferrocenyl complex is evident from the ~4 fold increase in its photocytotoxicity compared to the phenyl analogue. The apoptotic mode of cell death is evident from nuclear co-staining using Hoechst dye. Chapter VI describes the synthesis, characterization and photochemotherapeutic efficacy of ferrocene conjugates of N-alkyl pyridinium salts. Mitochondria targeting property of ferrocene compound having n-butyltriphenylphosphonium group has been studied by JC-1 assay. FACS analysis showed significant sub G1/G0 phase cell-cycle arrest in cancer cells on visible light treatment. Finally, the summary of the dissertation and conclusions drawn from the present investigations are presented. The references in the text have been indicated as superscript numbers and compiled at the end of each chapter. The complexes presented in this thesis are represented by bold-faced numbers. Crystallographic data of the structurally characterized complexes are given in CIF format in the enclosed CD (Appendix-I). Due acknowledgements have been made wherever the work described is based on the findings of other investigators. Any unintentional omission that might have happened due to oversight or mistake is regretted. INDEX WORDS: Ferrocene conjugates Crystal structure DNA binding DNA photocleavage Photocytotoxicity Vanadium Cellular Imaging
682

Pulsed I-V and RF characterization and modeling of AIGaN HEMTs and Graphene FETs / Caractérisation IV impulsionnelle et RF et Modélisation de AlGaN/GaN HEMT et graphène FET

Nakkala, Poornakarthik 18 June 2015 (has links)
Ces travaux de recherche se rapportent à l’évaluation des potentialités des transistors à base de graphène ainsi que la mise en évidence des effets dispersifs sur les transistors HEMTs en technologie Nitrure de Gallium. Les principaux résultats issus de ces travaux sont obtenus suite au développement d’un banc de caractérisation spécifique. L’objectif principal pour la caractérisation des transistors en technologie AlGaN/GaN a été de développer des techniques innovantes de caractérisation. Des mesures IV et RF impulsionnelles ont été réalisées afin de caractériser et modéliser les phénomènes de pièges. Cette méthode fournit un moyen efficace d’évaluer les constantes de temps thermiques et de pièges pour la modélisation non linéaire. Ces mesures illustrent ainsi l’impact des effets de pièges sur le comportement dynamique grand signal des transistors GaN. Le second aspect de ces travaux de recherche est axé sur la caractérisation de différents composants à base de graphène afin d’extraire un modèle non linéaire. Des caractérisations DC et HF ont été réalisées. Des structures spécifiques de test ont été fabriquées pour la technique de « de-embedding » permettant l’extraction du modèle non linéaire. La cohérence du modèle électrique a été vérifiée via une comparaison des paramètres S mesurés et simulés. Il est primordial de construire des modèles performants prenant en compte les nouvelles caractéristiques de ces dispositifs dans le but d’établir un lien fort entre les aspects technologiques et systèmes afin d’améliorer les performances HF des transistors à base de graphène. / The aim of this work is to assess the potentialities of Graphene Field Effect Transistors (G-FET) as well as to put in evidence dispersive effects of AlGaN/GaN High Electron Mobility Transistors (HEMTs). The main experimental results of this study have been obtained through the development of an advanced characterization set-up. The main objective for characterization of AlGaN/GaN HEMTs was to develop innovative characterization techniques such as very short pulses and electrical history measurements. Dedicated time-domain pulsed I-V measurements have been performed in order to characterize and model the time dependent trapping phenomena in such devices. The current collapse (Kink effect) and drain lag are directly related to quiescent and instantaneous bias points as well as thermal effects which play a prominent role. This method provides an efficient way to assess the different thermal and trapping time constants for the nonlinear modeling. The second aspect of this research work was the characterization of several graphene-based devices in order to assess the potentialities of such transistors and to derive a nonlinear device model. DC and high frequency characterization were performed. Specific test structures fabricated for accurate de-embedding at high frequencies along with the nonlinear model extraction were detailed in this work. This electrical model consistency has been checked through the comparison of measured and simulated multi-bias S-parameters. For this new material with outstanding electrical properties and promising capabilities, material and technological process are still subject to intensive research activities to improve high frequency graphene FET performances.
683

Delitos en la bancarrota : aspectos penales de la Ley 20.720, sobre reorganización y liquidación de empresas y personas

Ramírez Araya, Juan Pablo January 2016 (has links)
Memoria (licenciado en ciencias jurídicas y sociales)
684

Electrodeposition and characterisation of nickel-niobium-based diffusion barrier metallisations for high temperature electronics interconnections

Wang, Jing January 2016 (has links)
The control of interfacial microstructural stability is of utmost importance to the reliability of liquid solder interconnects in high temperature electronic assemblies. This is primarily due to excessive intermetallic compounds (IMCs) that can form and continuously grow during high temperature operation, which practically renders conventional barrier metallisations inadequate. In this study, electrically conducting, NbOx containing Ni coatings were developed using electrodeposition. Their suitability as a solder diffusion barrier layer was assessed in terms of the electrical conductivity and barrier property. The present work explores a novel electrochemical route to produce Ni-NbOx composite coatings of good uniformity, compactness and purity, from non-aqueous glycol-based electrolytes consisting of NiCl2 and NbCl5 as metal precursors. The effects of cathodic current density and NaBH4 concentrations on the surface morphology, composition and thickness of the coatings were examined. A combined study of Scanning Transmission Electron Microscopy (STEM) and Electrochemical Quartz Crystal Microbalance (EQCM) was conducted to understand the fundamental aspects of this novel electrodeposition process. The composite coatings generally exhibited good electrical conductivity. The reaction behaviour between a liquid 52In-48Sn solder and Ni-NbOx, with Nb contents up to 6 at.%, were studied at 200°C. The results indicate that, Ni-NbOx with sufficient layer thickness and higher Nb content, offered longer service lifetime. Nb enrichment was generally observed at or close to the reaction front after high temperature storage, which suggests evident effectiveness of the enhanced diffusion barrier characteristics.
685

Investigating the level of interdependency between the performance(s) of direct opponent(s) in professional football : a study on teams, positional units and individual players competing in the German Bundesliga

Jamil, Mikael January 2015 (has links)
The purpose of this thesis is to investigate the levels of interdependency (simultaneity) between the performances of two direct opponents in professional football. More specifically, interdependency between performances is investigated at three different levels. Firstly, empirical analyses are conducted in order to assess the levels of interdependency between the performances of two teams in direct competition using team-game observations. Secondly, data on team formations and player starting positions within these formations is utilised in order to uniquely match individual players to a sole opponent on the field of play. Further empirical analyses are then conducted in order to investigate the levels of interdependency at this more isolated individual player level using player-game observations. Finally, an empirical investigation into the levels of interdependency between the performances of a positional unit (defence or attack) and their opposing team (as a collective) is conducted using positional unit-game observations. An exclusive and detailed data set ranging from the 2007-08 season to the 2010-11 season is utilised in order to estimate several production functions for teams, individual players and positional units competing in the German Bundesliga. The results in all empirical analyses confirm that the performance of the opponent is significant. At a team and positional unit level, no evidence is found to suggest that the performances of two direct opponents(s) are interdependent, however the results reveal that the recent past performances of the opponent(s) have a significant linear impact upon the performance of the subject. In particular, relative team form going in to a match is revealed to have a significant impact upon the performance of their opponent. At an individual player level, evidence is found to confirm that the performances of players in direct competition are interdependent thus supporting the sports economics theory of joint production. Specifically, the results reveal that the performances of defenders have a significant and negative impact upon the performances of their opposing attackers.
686

Characterization Techniques and Optimization Principles for Multi-Junction Solar Cells and Maximum Long Term Performance of CPV Systems

Yandt, Mark January 2017 (has links)
Two related bodies of work are presented, both of which aim to further the rapid development of next generation concentrating photovoltaic systems using high efficiency multi junction solar cells. They are complementary since the characterization of commercial devices and the systematic application of design principles for future designs must progress in parallel in order to accelerate iterative improvements. First addressed, is the field characterization of state of the art concentrating photovoltaic systems. Performance modeling and root cause analysis of deviations from the modeling results are critical for bringing reliable high value products to the market. Two complementary tools are presented that facilitate acceleration of the development cycle. The “Dynamic real-time I V Curve Measurement System…” provides a live picture of the current-voltage characteristics of a CPV module. This provides the user with an intuitive understanding of how module performance responds under perturbation. The “Shutter technique for noninvasive individual cell characterization in sealed concentrating photovoltaic modules,” allows the user to probe individual cell characteristics within a sealed module. This facilitates non-invasive characterization of modules that are in situ. Together, these tools were used to diagnose the wide spread failure of epoxy connections between the carrier and the emitter of bypass diodes installed in sealed commercial modules. Next, the optimization principals that are used to choose energy yield maximizing bandgap combinations for multi-junction solar cells are investigated. It is well understood that, due to differences in the solar resource in different geographical locations, this is fundamentally a local optimization problem. However, until now, a robust methodology for determining the influences of geography and atmospheric content on the ideal design point has not been developed. This analysis is presented and the influence of changing environment on the representative spectra that are used to optimize bandgap combinations is demonstrated. Calculations are confirmed with ground measurements in Ottawa, Canada and the global trends are refined for this particular location. Further, as cell designers begin to take advantage of more flexible manufacturing processes, it is critical to know if and how optimization criteria must change for solar cells with more junctions. This analysis is expanded to account for the differences between cells with up to 8 subcell bandgaps. A number of software tools were also developed for the Sunlab during this work. A multi-junction solar cell model calibration tool was developed to determine the parameters that describe each subcell. The tool fits a two diode model to temperature dependent measurements of each subcell and provides the fitting parameters so that the performance of multi-junction solar cells composed of those subcells can be modeled for real world conditions before they are put on-sun. A multi-junction bandgap optimization tool was developed to more quickly and robustly determine the ideal bandgap combinations for a set of input spectra. The optimization process outputs the current results during iteration so that they may be visualized. Finally, software tools that compute annual energy yield for input multi-junction cell parameters were developed. Both a brute force tool that computes energy harvested at each time step, and an accelerated tool that first bins time steps into discrete bins were developed. These tools will continue to be used by members of the Sunlab.
687

A atuação pública dos bispos no principado de Constantino = as transformações ocorridas no Império e na Igreja no início do século IV através dos textos de Eusébio de Cesaréia / The public role of the bishops in the reign of Constantine : the transformations occurred within Church and Empire in the beginning of the fourth century through the texts of Eusebius of Caesarea

Della Torre, Robson Murilo Grando, 1986- 18 August 2018 (has links)
Orientador: Néri de Barros Almeida / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Filosofia e Ciências Humanas / Made available in DSpace on 2018-08-18T15:57:27Z (GMT). No. of bitstreams: 1 DellaTorre_RobsonMuriloGrando_M.pdf: 2698271 bytes, checksum: f0b68c5e003758f15d45bb8c9ee053c8 (MD5) Previous issue date: 2011 / Resumo: Esta dissertação tem por objetivo analisar a atuação pública dos bispos durante o principado de Constantino, sobretudo seus esforços de construir uma relação de proximidade e de diálogo com a corte imperial. O corpus documental principal deste estudo é constituído pelos textos do bispo Eusébio de Cesaréia que lidam especialmente com este imperador, quais sejam: a História Eclesiástica, o Louvor a Constantino e a Vida de Constantino. Tentarei mostrar, através destes textos, como a política de favorecimento imperial ao cristianismo que se verifica no início do século IV deve muito de seu sucesso à participação política dos bispos junto ao imperador e seus altos magistrados, residindo o problema da consolidação da Igreja como instituição política importante no cenário imperial não só em uma mudança de atitude do príncipe frente às comunidades cristãs, mas sobretudo em uma transformação ocorrida nas igrejas, por meio de seus bispos, que cada vez mais interessadas no auxílio de Roma para a resolução de seus conflitos / Abstract: This dissertation has as its main aim to analyze the public role of the bishops during the reign of Constantine, chiefly their efforts to build a relationship of proximity and dialogue with the imperial court. The documental corpus of this study is composed of the texts of the bishop Eusebius of Caesarea that deal specially with this emperor, which are the Ecclesiastical History, the Praise of Constantine and the Life of Constantine. I will try to show how the imperial policy of support to Christianity that occurs in the beginning of the fourth century owes great part of its success to the political involvement of the bishops with the emperor and his magistrates. I will also argue that the problem of the consolidation of the Church as an important political institution within the imperial scenario depends not only of a change of attitude of the emperor towards the Christian communities, but mainly of a transformation occurred within the churches themselves, through their bishops, that were more and more interested in the aid of Rome for the resolution of their own conflicts / Mestrado / Historia Cultural / Mestre em História
688

Development, assessment and application of computational tools for design safety analysis of liquid metal cooled fast breeder reactors

Lázaro Chueca, Aurelio 03 September 2014 (has links)
El Generation IV International Forum (GIF) [1] es un programa internacional dedicado a apoyar, coordinar y dirigir las iniciativas de investigación y desarrollo encaminados a implementar las soluciones tecnológicas que caracterizarán a la siguiente generación de reactores nucleares. Estos reactores se caracterizaran por una gestión más eficiente del combustible nuclear, un incremento en las exigencias de seguridad y una alta competitividad económica. Con tales objetivos, GIF propuso una serie de diseños potencialmente capaces de alcanzarlos. Estos diseños son tecnológicamente muy distintos a las plantas nucleares comerciales actuales al utilizar neutrones de espectro rápido y consecuentemente refrigeración por metales líquidos. Estos nuevos diseños requieren el desarrollo y validación de herramientas computacionales capaces de simular el comportamiento de la planta tanto en fase estacionaria como en transitoria y por tanto sean aplicables en los procesos de diseño y licitación de dichas plantas. El objetivo de esta tesis es el de adaptar los códigos computacionales actuales aplicados a la simulación de reactores refrigerados por agua a reactores rápidos refrigerados por metales líquidos, tales como el sodio o el plomo y el desarrollo de modelos capaces de simular de una manera consistente el comportamientos de los sistemas ante determinados eventos que constituyen la base de diseño de la planta Para ello se adaptaran dichos códigos a la fenomenología específica de estos reactores, se desarrollaran modelos termo-hidráulicos y neutrónicos tanto unidimensionales como tridimensionales de los diseños propuestos y se validarán los resultados para demostrar su aplicabilidad. El trabajo incluye la implementación de correlaciones específicas para habilitar los códigos para el cálculo de la condiciones termo-hidráulicas de los refrigerantes así como la adaptación de los esquemas de acoplamiento termo-hidráulico-neutrónicos existentes a esta nueva tecnología. / Lázaro Chueca, A. (2014). Development, assessment and application of computational tools for design safety analysis of liquid metal cooled fast breeder reactors [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/39353 / TESIS
689

Shakespeare's Bolingbroke: Rhetoric and stylistics from Richard II to Henry IV, part 2

Jenson, DeAnna Faye 01 January 2004 (has links)
In order to contribute to the body of work on Bolingbroke and on Shakespeare's development of character, this thesis examines various rhetorical and stylistic methods used by Shakespeare in his creation of the character of Henry Bolingbroke.
690

Visualization of procollagen IV reveals ER-to-Golgi transport by ERGIC-independent carriers / IV型プロコラーゲン輸送を可視化して解析し、小胞体からゴルジ装置への輸送はERGIC非依存性であることを解明した

Matsui, Yuto 24 November 2020 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第22832号 / 医博第4671号 / 新制||医||1047(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 林 康紀, 教授 安達 泰治, 教授 岩田 想 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

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