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1
Khademi, Ali. "Tuning graphene’s electronic and transport properties via adatom deposition." Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/62588.
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This thesis investigates the effect of adatom deposition, especially alkali and heavy
adatoms, on graphene’s electronic and transport properties. While there are many
theoretical predictions for tuning graphene’s properties via adatom deposition, only
a few of them have been observed. Solving this enigma of inconsistency between
theory and experiment raises the need for deeper experimental investigation of this
matter. To achieve this goal, an experimental set up was built which enables us to
evaporate different metal adatoms on graphene samples while they are at cryogenic
temperatures and ultra-high vacuum (UHV) conditions.
The critical role of in situ high-temperature annealing in creating reliable interactions
between adatoms and graphene is observed. This contradicts the commonly
accepted assumption in the transport community that placing a graphene sample in
UHV and performing in situ 400-500 K annealing is enough to provide a reliable
adatom-graphene interaction. Even charge doping by alkali atoms (Li), which is
arguably the simplest of all adatom effects, cannot be achieved completely without
in situ 900 K annealing. This observation may explain the difficulty many
groups have faced in inducing superconductivity, spin-orbit interaction, or similar
electronic modifications to graphene by adatom deposition, and it points toward a
straightforward, if experimentally challenging, solution.
The first experimental evidence of short-range scattering due to alkali adatoms
in graphene is presented in this thesis, a result that contradicts the naive expectation
that alkali adatoms on graphene only cause long-range Coulomb scattering.
The induced short-range scattering by Li caused decline of intervalley time and
length (i.e., enhancement of intervalley scattering). No signatures of theoretically
predicted superconductivity of Li doped graphene were observed down to 3 K. Cryogenic deposition of copper increased the dephasing rate of graphene. This
increase in dephasing rate is either a sign of inducing spin-orbit interaction or magnetic
moments by copper. No similar effect was observed for indium.Science, Faculty of
Physics and Astronomy, Department of
Graduate
2
Chacha, Joseph S. "Solvent, anion and temperature effects in UPD lead adatom array formation at gold electrodes." Thesis, University of Ottawa (Canada), 1989. http://hdl.handle.net/10393/5727.
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Adler, Florian Rudolf [Verfasser], Ralph [Gutachter] Claessen, and Matthias [Gutachter] Bode. "Electronic Correlations in Two-dimensional Triangular Adatom Lattices / Florian Rudolf Adler ; Gutachter: Ralph Claessen, Matthias Bode." Würzburg : Universität Würzburg, 2021. http://d-nb.info/124061473X/34.
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St, John Samuel. "Hierarchical Electrocatalyst Structure Control to Study Cathodic and Anodic Overpotential in Proton Exchange Membrane Fuel Cells." University of Cincinnati / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1384334674.
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Schuwalow, Sergej [Verfasser], and Frank [Akademischer Betreuer] Lechermann. "Magnetic adatom structures on semiconductor surfaces in presence of strong electronic correlations / Sergej Schuwalow. Betreuer: Frank Lechermann." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2012. http://d-nb.info/1027573967/34.
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LePage, Jeffrey Guy. "Projector-augmented wave method calculation of Ga adatom diffusion and local density of states for GaAs and Si surfaces /." The Ohio State University, 1997. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487943341528438.
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Žguns, Pjotrs. "First Principles Modelling of Clean Energy Materials." Licentiate thesis, KTH, Flerskalig materialmodellering, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-166864.
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This licentiate thesis presents the density functional theory study on clean energy materials relevant for catalysis applications, and for solid oxide fuel cells. In the first part of the thesis the metal supported ultrathin films, namely ScN/Mo, MgO/Mo and NaF/Mo are considered, and the Cu atom adsorption and charging on them is explored.The comparative study of these different films allows us to provide recommendations regarding the choice of materials, in order to promote adatom charging. The modulation of the adatom charge, by changing the material of the film, also paves the way for the design of novel catalysts. Moreover, the detailed investigation of the Cu/NaF/Mo caseshows a correlation between the charge redistribution upon the adsorption and the anharmonicity of the accompanying distortion. Overall, the research commands a fresh view on the adatom charging mechanism. In the second part of the thesis the gadolinium doped ceria, used asoxide electrolyte in solid oxide fuel cells, is studied. The employment of the cluster expansion method together with the density functional theory calculations provides the description of the configurational energy spectrum of dopants and oxygen vacancies in terms of effective pair and three site interactions. The chosen method allows one to predict the energy of anarbitrary configuration. Moreover, the effect of volume change on the strength of interactions is investigated, which is relevant for the modelling ofoxide electrolytes at operating temperatures of solid oxide fuel cells,i.e. when volume expansion is notable.QC 20150521
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Tonnis, Kevin M. "The Electrocatalytic Behavior of Bismuth-Modified Platinum: Platinum-Bismuth Alloy versus Bismuth Adatoms." University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1592136754408934.
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Porter, Christopher Douglas. "Topics in the Theory of Josephson Arrays and Disordered Magnetic Systems." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1315459079.
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ACHILLI, SIMONA. "Spectral properties of adsorbates on metal surfaces via the embedding method." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2010. http://hdl.handle.net/10281/10827.
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Adsorbates on metal surfaces have attracted recently the scientific interest both from a fundamental point of view (quantum confinement) and in perspective of application in technology. In particular the electronic properties of such reduced symmetry systems are strictly related to their low dimensionality. An accurate theoretical description of their spectral properties has necessarily to deal with the absence of periodicity that characterizes these systems in one (thin films) or more (adatoms) directions. The embedding method allows to overcome this drawback considering a really infinite system both on vacuum and bulk side. In this thesis the ab initio spectral properties of single adatoms (alkali-metal atom and Ba) on Cu(111) and thin overlayers (K/Cu(111), Bi/Cu(100), O/Fe(100)) are analyzed, also in comparison with experimental results. The capabilities of the theoretical method adopted allow to evidence the role of the substrate band structure on the adsorbates induced electronic states. In particular the aspects related to the resonant charge transfer from the adsorbate's states to the bulk continuum are analyzed. This process represents an elastic decay channel for the surface electronic states and contributes to the elastic lifetime, that we can estimate according to the description of a continuous substrate band structure. The results presented for single adatoms evidence the blockade effect that a surface projected energy gap of the substrate produces on the resonant charge transfer. On the other hand the results relative to the overlayer allows to analyze the complex hybridization mechanism between surface features and substrate states in different points of the surface Brillouin zone.
In addition the theoretical description of the electronic properties of overlayers on metal surfaces is devoted in this thesis also to the simulation of experimental findings, namely STM and STS images and photoemission spectra, showing the predictive character of the theoretical approach used.
11
Cafe, Peter F. "Towards reliable contacts of molecular electronic devices to gold electrodes." Thesis, The University of Sydney, 2008. http://hdl.handle.net/2123/3870.
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SYNOPSIS OF THIS THESIS The aim of this thesis is to more fully understand and explain the binding mechanism of organic molecules to the Au(111) surface and to explore the conduction of such molecules. It consists of five discreet chapters connected to each other by the central theme of “The Single Molecule Device: Conductance and Binding”. There is a deliberate concentration on azine linkers, in particular those with a 1,10-phenanthroline-type bidentate configuration at each end. This linker unit is called a “molecular alligator clip” and is investigated as an alternative to the thiol linker unit more commonly used. Chapter 1 places the work in the broad context of Molecular Electronics and establishes the need for this research. In Chapter 2 the multiple break-junction technique (using a Scanning Tunnelling Microscope or similar device) was used to investigate the conductance of various molecules with azine linkers. A major finding of those experiments is that solvent interactions are a key factor in the conductance signal of particular molecules. Some solvents interfere with the molecule’s interaction with and attachment to the gold electrodes. One indicator of the degree of this interference is the extent of the enhancement or otherwise of the gold quantized conduction peak at 1.0 G0. Below 1.0 G0 a broad range for which the molecule enhances conduction indicates that solvent interactions contribute to a variety of structures which could bridge the electrodes, each with their own specific conductance value. The use of histograms with a Log10 scale for conductance proved useful for observing broad range features. vi Another factor which affects the conductance signal is the geometric alignment of the molecule (or the molecule-solvent structure) to the gold electrode, and the molecular alignment is explored in Chapters 3 for 1,10-phenanthroline (PHEN) and Chapter 4 for thiols. In Chapter 3 STM images, electrochemistry, and Density Functional Theory (DFT) are used to determine 1,10-phenanthroline (PHEN) structures on the Au(111) surface. It is established that PHEN binds in two modes, a physisorbed state and a chemisorbed state. The chemisorbed state is more stable and involves the extraction of gold from the bulk to form adatom-PHEN entities which are highly mobile on the gold surface. Surface pitting is viewed as evidential of the formation of the adatom-molecule entities. DFT calculations in this chapter were performed by Ante Bilic and Jeffery Reimers. The conclusions to Chapter 3 implicate the adatom as a binding mode of thiols to gold and this is explored in Chapter 4 by a timely review of nascent research in the field. The adatom motif is identified as the major binding structure for thiol terminated molecules to gold, using the explanation of surface pitting in Chapter 3 as major evidence and substantiated by emergent literature, both experimental and theoretical. Furthermore, the effect of this binding mode on conductance is explored and structures relevant to the break-junction experiment of Chapter 2 are identified and their conductance values compared. Finally, as a result of researching extensive reports of molecular conductance values, and having attempted the same, a simple method for predicting the conductance of single molecules is presented based upon the tunneling conductance formula.
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Cafe, Peter F. "Towards reliable contacts of molecular electronic devices to gold electrodes." University of Sydney, 2008. http://hdl.handle.net/2123/3870.
Full textAbstract:
PhDSYNOPSIS OF THIS THESIS The aim of this thesis is to more fully understand and explain the binding mechanism of organic molecules to the Au(111) surface and to explore the conduction of such molecules. It consists of five discreet chapters connected to each other by the central theme of “The Single Molecule Device: Conductance and Binding”. There is a deliberate concentration on azine linkers, in particular those with a 1,10-phenanthroline-type bidentate configuration at each end. This linker unit is called a “molecular alligator clip” and is investigated as an alternative to the thiol linker unit more commonly used. Chapter 1 places the work in the broad context of Molecular Electronics and establishes the need for this research. In Chapter 2 the multiple break-junction technique (using a Scanning Tunnelling Microscope or similar device) was used to investigate the conductance of various molecules with azine linkers. A major finding of those experiments is that solvent interactions are a key factor in the conductance signal of particular molecules. Some solvents interfere with the molecule’s interaction with and attachment to the gold electrodes. One indicator of the degree of this interference is the extent of the enhancement or otherwise of the gold quantized conduction peak at 1.0 G0. Below 1.0 G0 a broad range for which the molecule enhances conduction indicates that solvent interactions contribute to a variety of structures which could bridge the electrodes, each with their own specific conductance value. The use of histograms with a Log10 scale for conductance proved useful for observing broad range features. vi Another factor which affects the conductance signal is the geometric alignment of the molecule (or the molecule-solvent structure) to the gold electrode, and the molecular alignment is explored in Chapters 3 for 1,10-phenanthroline (PHEN) and Chapter 4 for thiols. In Chapter 3 STM images, electrochemistry, and Density Functional Theory (DFT) are used to determine 1,10-phenanthroline (PHEN) structures on the Au(111) surface. It is established that PHEN binds in two modes, a physisorbed state and a chemisorbed state. The chemisorbed state is more stable and involves the extraction of gold from the bulk to form adatom-PHEN entities which are highly mobile on the gold surface. Surface pitting is viewed as evidential of the formation of the adatom-molecule entities. DFT calculations in this chapter were performed by Ante Bilic and Jeffery Reimers. The conclusions to Chapter 3 implicate the adatom as a binding mode of thiols to gold and this is explored in Chapter 4 by a timely review of nascent research in the field. The adatom motif is identified as the major binding structure for thiol terminated molecules to gold, using the explanation of surface pitting in Chapter 3 as major evidence and substantiated by emergent literature, both experimental and theoretical. Furthermore, the effect of this binding mode on conductance is explored and structures relevant to the break-junction experiment of Chapter 2 are identified and their conductance values compared. Finally, as a result of researching extensive reports of molecular conductance values, and having attempted the same, a simple method for predicting the conductance of single molecules is presented based upon the tunneling conductance formula.
13
Monir, Md M. "A COMPUTATIONAL INVESTIGATION OF SECTORAL ZONING OF RARE EARTH ELEMENTS (REE) IN FLUORITE." Miami University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=miami1438881165.
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CASARTELLI, MARINA. "POINT DEFECTS AND ADATOMS AT SURFACES:CHALLENGES AND OPPORTUNITIES." Doctoral thesis, Università degli Studi di Milano, 2014. http://hdl.handle.net/2434/229252.
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In many occasions defects have been proved to be an opportunity more than a limit, as they may be used to tailor the properties of a given material. To this end, a practical route to introduce a
controlled amount of defects as well as a deep knowledge of the defect nature is always desirable.
As well, recombinative and dissociative processes involving gas molecules are well known to likely occur on metal surfaces, that may then be used in a number of industrial applications. In this thesis I report on both the isolated carbon atom vacancy, that is a common lattice defect in graphene,
and the Eley-Rideal formation of H2 molecules in the limit of an single adsorbed atom on the Ag(111) surface. In the first part of this thesis I consider the details of the electronic structure in the neighbourhoods of a carbon atom vacancy in graphene by employing magnetisation-constrained density-functional theory on periodic slabs, and spin-exact, multi-reference, second-order perturbation theory on a finite cluster. The picture that emerges is that of two local magnetic moments (one sigma-like and one pi-like) decoupled from the pi-band and coupled to each other. The ground state is
identified as a triplet with a planar equilibrium geometry resulting upon a Jahn-Teller distortion, in
which an apical C atom opposes a pentagonal ring. This state lies 0.2 eV lower in energy than the
open-shell singlet with one spin flipped, which is a bistable system with two equivalent equilibrium
lattice configurations (for the apical C atom above or below the lattice plane) and a barrier 0.1 eV
high separating them. Accordingly, a bare carbon-atom vacancy is predicted to be a spin-one paramagnetic
species, but spin-half paramagnetism can be accommodated if binding to foreign species, ripples, coupling to a substrate, or doping are taken into account.
In the second part, I study by DFT means the process of hydrogenation of the carbon vacancy, starting from the bare defect atom up to the case of six hydrogen atoms chemisorbed onto its nearest neighbours. I initially consider the formation of a mono-hydrogenated vacancy, finding a binding
energy of 4.2 eV and no activation barrier to the adsorption. As well, I study a variety of possible
mutual arrangements of the adsorbates at higher coverages discussing their reactivity and local magnetic
moments. In this way the overall hydrogenation process turns out to be thermodynamically favoured and exothermic with respect to both atomic and molecular hydrogen gas sources at least up to four H atoms. This follows from the fact that the driving force in this process is the saturation
of the (3sigma + 1pi) unpaired electrons at the vacancy. Moreover, these DFT energies are used to build a
phase diagram in a broad range of temperatures and H2 partial pressures, thus finding that at room T and p conditions, the magnetic (M = 1muB) 3H-anti structure is the most stable in agreement with recent magnetic measurements. In addition, by considering the stable phase at TEM conditions, it seems reasonable to identify the recently detected three-fold and distorted vacancy with the 3H-anti and the 1H vacancy, respectively. In the end, in these calculations the 2H-geminal phase detected in muSR experiments, is found to be unfavoured both from a thermodynamic and a kinetic point of view with respect to other di-hydrogenated structures.
In the third part I consider the formation of hydrogen molecules on the Ag(111) surface by abstraction
of the adsorbed H atom according to the Eley-Rideal reaction mechanism. To follow the time evolution of the system, I rely on ab initio molecular dynamics and on the quasiclassical trajectory
method based onto an external potential energy surface, originally built for quantum calculations on the same system within the flat and rigid surface approximation. In general the reaction is not activated, in fact it has a sizeable cross section even at collision energies in the order of few meV.
In terms of cross sections, the differences between ab initio and quasiclassical results at collision
energies below 0.5 eV are proved to depend on the surface corrugation and the energy exchange between hydrogen atoms and surface atoms, which are ignored in the quasiclassical study, following from the reference PES used. In this energy interval, the target vibration may be safely neglected
but this is not the case for higher collision energies where it strongly affects the final outcome.
Moreover, by considering the product molecules the reaction mechanism is identified as mainly
based on a non-collinear scheme with the reactive encounter occurring upon a bounce of the incident atom on the surface. By means of all these dynamics calculations a large cross-section (compared to the typical value on transition metals) is found in quite good agreement with a recent experimental estimate at very low coverage. Anyway, in future in order to get closer to the experimental result,
it seems to be necessary to account for the initial surface temperature, the surface precoverage and the incident angle of the incoming atoms.
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Diaz, Michel. "Bibliographie d'Arthur Adamov (1926-1993) : œuvres d'Adamov, écrits sur Adamov, textes joués." Tours, 1994. http://www.theses.fr/1994TOUR2033.
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Le premier tome de la thèse est une bibliographie qui réunit le maximum de références et d'indications concernant les œuvres d'Arthur Adamov, les textes critiques sur Adamov, la représentation et la diffusion de ses pièces (originales et adaptations). Couvrant la période qui va de 1926 à 1993-(94), elle se veut un outil de recherche précis, efficace, et aussi à jour que possible. Tables et index qui la complètent utilement permettent aussi d'en varier le maniement. Le second tome propose un copieux corpus de textes d'Adamov non encore publiés en volume (textes de jeunesse, poèmes, textes théoriques sur le théâtre, articles et interviews) qui couvre toute sa carrière littéraire (19261970). Présentations et annotations tachent de replacer ces écrits dans le contexte de leur production (politique, social, littéraire, théâtral), de saisir la genèse de l'œuvre, et de dégager les aspects qui la rendent digne d'occuper une place de premier plan dans la littérature dramatique française du XXe siècleThis first part of the thesis is a bibliography compiling the maximum of references and information concerning A. Adamov's works, the critiques about Adamov, the performances of the broadcasting of his plays (the original plays ad well as the adaptations). This bibliography covering the 1926-1993-(94) period is intended to be an accurate, efficient and as updated as possible research tool. A supplement of tables and indexes usefully adds to the bibliography; it is indeed designed in order to allow a great deal of different uses and approaches. The second part of the thesis offers a lavish corpus of texts by Adamov which have not yet been published in a volume (texts written during his youth, poems theoretical texts about theatre, articles and interviews); these texts cover the whole of his literary career (1926-1970). The presentations and annotations try to reset these writings into the political, social literary and theatrical context of their creation. This volume also aims at sing
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Toman, Radim. "Studie rekonstrukce žst. Adamov." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2018. http://www.nusl.cz/ntk/nusl-372010.
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The aim of the master's thesis is a reconstruction of the Adamov railway station. The goal is to design new platforms suitable for passengers with reduced mobility and orientation. The thesis constains modification of track geometry parameters of the railway, reconstruction of the railway superstructure and railway substructure. There are two new off-level platforms at the station
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Månsson, Martin. "Adatoms, Quasiparticles & Photons : The Multifaceted World of Photoelectron Spectroscopy." Doctoral thesis, KTH, Mikroelektronik och tillämpad fysik, MAP, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4659.
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The experimental work presented in this thesis is based on a wide assortment of very advanced and highly sophisticated photoelectron spectroscopy (PES) techniques. The objective of the present study has been to reveal and understand the electronic structure and electron dynamics in a broad spectrum of materials, ranging from wide band gap oxides, via semiconductors along with metals, and finally high-temperature superconductors. The first part of the thesis concerns laser-based pump-and-probe PES. This unique experimental technique has permitted a study of the excited electronic structure and the electron dynamics of several semiconductor surfaces. An insight into details of the adatom to restatom charge-transfer of the Ge(111)c(2x8) surface is presented, as well as an estimate for the timescale in which the dynamic adatoms of the Ge(111):Sn(sqrt3xsqrt3)R30deg surface operate. Further results comprise a novel unoccupied surface state at the GaSb(001) surface as well as a time-resolved study of the charge accumulation layer at the InAs(111)A/B surfaces. In the second part, high-resolution synchrotron based angle-resolved PES (ARPES) data from the cuprate high-temperature superconductor La(2-x)Sr(x)CuO(4) (LSCO) is presented. This extensive study, reveals detailed information about how the Fermi surface and electronic excitations evolve with doping in the superconducting state. The results comprise support for a connection between high- and low-energy electronic responses, the characteristics of the superconducting gap, and indication of a quantum phase transition between two different superconducting phases. In the third group of experiments we move away from the two-dimensional systems and concentrate on fully three-dimensional compounds. By the use of soft x-ray ARPES it is possible to extract the three-dimensional electronic structure in a straightforward manner with increased k(perpendicular)-resolution. As a result the first high-quality ARPES data from Cu2O is presented, as well as a novel method for extracting the (real space) electron density by ARPES. These experiments clearly display the advantages of using soft x-ray ARPES. If the material and type of experiment is chosen wisely, the benefit of the increased k||-window and the free electron final state, surpass the drawbacks of decreased count-rate and inferior energy resolution. Finally we return to the high-temperature superconductors (NCCO & Nd-LSCO) and make use of the increased bulk-sensitivity. From an evident change in the shape of the Fermi surface when moving from low to high photon energies, the durface to bulk difference in electronic structure is highlighted.QC 20100810
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Penteado, Poliana Heiffig. "Transport through leaked Majorana modes in quantum dots and adatoms." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/76/76131/tde-13012014-135024/.
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We investigate quantum resonant transport in two different systems: (i) a ferromagnetic Scanning Tunneling Microscope (STM) tip coupled to an adatom (interacting) on a host surface (metallic or semiconductor), and (ii) a quantum dot connected to source and drain leads and side-coupled to a superconducting nanowire sustaining Majorana zero modes (Kitaev chain). Both problems are studied within the Green’s functions approach, which allows us to determine the transport properties of the system. In the first setup, due to the ferromagnetic and nonmagnetic ‘natures’ of the tip and host, respectively, it is possible to obtain the spin-diode effect, which occurs only in the singly occupied regime. In addition, because of the presence of the adsorbed atom on the surface, Friedel oscillations are observed in the current. The second system differs from the first mainly because it is spinless and there is no Coloumb interaction. Interestingly, we find that the Majorana mode of the wire leaks into the dot thus giving rise to a Majorana (zero mode) resonance in the dot, pinned to the Fermi level of the leads. Surprisingly, this resonance occurs even when the gate-controlled dot level is far above or far below the Fermi level of the leads. We study three possible experimental scenarios to probe unambigoulsy this Majorana mode in wires via these leaked/pinned modes.Nesta tese investigamos transporte quântico ressonante em dois sistemas diferentes: (i) uma ponta STM ferromagnética acoplada a um átomo (interagente) adsorvido em uma superfície metálica ou semicondutora, e (ii) um ponto quântico conectado a reservatórios de elétrons e lateralmente acoplado a um nanofio supercondutor que possui modos de Majorana (cadeia Kitaev). Ambos os problemas são estudados no contexto de funções de Green, o que nos permite determinar as propriedades de transporte do sistema. Na primeira configuração, devido à natureza ferromagnética e não magnética da ponta STM e da superfície e, respectivamente, é possível obter o efeito diodo de spin, que ocorre apenas no regime em que o adátomo está ocupado com um único elétron. Além disso, por causa da presença do átomo adsorvido sobre a superfície, oscilções de Friedel são observadas na corrente. O segundo sistema é diferente do primeiro, principalmente pela ausência da interação de Coloumb e pelo fato de não ter spin. Curiosamente, vemos que o modo de Majorana do fio vai para o ponto quântico dando origem assim a um modo com energia zero no ponto quântico localizado sempre no nível de Fermi dos contatos. Surpreendentemente, essa ressonância ocorre mesmo quando o nível do ponto quântico, controlado por uma tensão externa, está muito acima ou muito abaixo do nível de Fermi dos contatos. Propomos três possíveis cenários experimentais para identificar de maneira conclusiva este modo de Majorana em fios através do modo que aparece no ponto quântico.
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Zalineeva, Anna. "Influence d'une modification par des éléments du groupe p de catalyseurs de palladium nanostructurés sur l'oxydation électrocatalytique du glycérol." Thesis, Poitiers, 2014. http://www.theses.fr/2014POIT2276/document.
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Les stocks de glycérol à travers le monde augmentent, étant une matière première secondaire, ce produit chimique doit être valorisé. La co-production d'énergie électrique ou d'hydrogène et de produits chimiques à valeur ajoutée à partir du glycérol peut être réalisée dans des réacteurs électrochimiques. L'oxydation de glycérol est une réaction complexe qui peut conduire à un grand nombre de produits chimiques et d'intermédiaires utiles pour l'industrie. Le développement de catalyseurs spécifiques pour orienter les chemins réactionnels de l'électrooxydation du glycérol vers les produits désirés est un objectif très important. Des nanoparticules non supportées de palladium à distribution de taille et de forme contrôlées ont été synthétisées par une voie colloïdale et caractérisées par microscopie électronique et des méthodes électrochimiques afin d'obtenir une corrélation entre la structure de surface et la réponse électrochimique. Ces électrolyseurs modèles ont été modifiés par dépôt d'adatomes de bismuth. Et leur activité et sélectivité vis-à-vis de l'électrooxydation du glycérol ont été respectivement évaluées par voltammétrie cyclique et spectroscopie infrarouge in situ. Des matériaux plus proches d'applications industrielles à base de palladium et d'éléments du groupe p (Bi, Sn) ont ensuite été aussi synthétisés et évalués vis-à-vis de l'électrooxydation du glycérol. Les résultats obtenus montrent clairement l'influence de la composition, de l'orientation de surface et de la nature de catalyseur sur l'activité et la sélectivité dans la réaction de l'électrooxydation du glycérolThe worldwide glycerol stocks are increasing; this chemical could be used as a secondary primary raw material. Electric energy or hydrogen and added-value-chemical cogeneration can be performed in electrochemical reactors. Glycerol oxidation is made up of complex pathway reactions that can produce a large number of useful products and valuable fine intermediates.The development of specific catalysts for electrooxidation of glycerol to obtain desired products is a very important goal.Unsupported palladium nanoparticles with controlled size and shape distribution were synthesized by a colloidal method and characterized by electron microscopy and electrochemical methods to obtain a correlation between the surface structure and the electrochemical response. These model electrocatalists have been modified by adatoms of bismuth. And their activity and selectivity towards the electrooxidation of glycerol were respectively evaluated by cyclic voltammetry and in situ infrared spectroscopy. Other materials for industrial applications based on palladium and p elements (Bi, Sn) were also synthesized and evaluated towards the electrooxidation of glycerol.The results clearly show the influence of the composition, surface orientation and the nature of the catalyst on activity and selectivity in the reaction of electrooxidation of glycerol
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Kvashnin, D. G., P. B. Sorokin, G. Seifert, and L. A. Chernozatonskii. "MoS₂ decoration by Mo-atoms and the MoS₂– Mo–graphene heterostructure: a theoretical study." Royal Society of Chemistry, 2015. https://tud.qucosa.de/id/qucosa%3A36376.
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Here we propose a completely new covalent heterostructure based on graphene and self-decorated MoS₂ monolayers. Detailed investigation of the decoration process of the MoS₂ surface by Mo adatoms was performed using first principles DFT methods. Comparison between valence-only and semicore pseudopotentials was performed to correctly describe the interaction between Mo adatoms and the MoS₂ surface. It was found that self-decoration by Mo atoms is favorable from an energetic point of view. We studied in detail various decoration paths of Mo atoms on the MoS₂ surface. The strong variation of electronic properties after the decoration of MoS₂ was found. The impact of the presence of Mo adatoms on the electronic properties of the graphene/MoS₂ heterostructure was shown.
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Sato, Masahide, Makio Uwaha, and Yukio Saito. "Step Bunching Induced by Drift of Adatoms with Anisotropic Surface Diffusion." Elsevier, 2002. http://hdl.handle.net/2237/7319.
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Gyamfi, Mike [Verfasser]. "Scanning Tunneling Microscopy and Spectroscopy of Adatoms on Graphene / Mike Gyamfi." München : Verlag Dr. Hut, 2012. http://d-nb.info/1025821254/34.
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Märkl, Junji Tobias [Verfasser]. "Investigation of Magnetic Adatoms with Scanning Tunneling Techniques / Junji Tobias Märkl." Karlsruhe : KIT Scientific Publishing, 2016. http://www.ksp.kit.edu.
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Page, Lesley J. "Adaptor targeting and subunit interactions." Thesis, University of Cambridge, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285255.
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Abdelmoula, Néjib. "La dramaturgie subjective d'Arthur Adamov." Paris 3, 2005. http://www.theses.fr/2005PA030082.
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Cette recherche concerne la vie et l'œuvre d'Arthur Adamov, écrivain et dramaturge français d'origine russe. Elle porte sur l'aspect subjectif de ses pièces et textes autobiographiques. La première partie de notre investigation tente de mettre en évidence le côté subjectif de l'écriture adamovienne. Elle montre la différence entre la subjectivité spontanée et la subjectivité cadrée, à travers l'étude de L'Aveu, La Parodie et Le Ping-Pong. La deuxième partie commence par un chapitre où nous étudions l'Autre dans le monde de l'auteur. Un Autre qui se divise en plusieurs facettes. Ensuite nous analysons deux pièces représentatives : Paolo Paoli et Le Printemps 71. La troisième partie investit le terrain de la dualité, plusieurs dualités sont relevées autour de l'homme Adamov. La dualité, du subjectif et de l'objectif, est analysée à travers Off limits et Si l'été revenait. Cette dernière partie est le lieu de rencontre entre le Moi, l'Autre et le Monde dans l'œuvre adamovienneThe present piece of research deals with the life and the work of Arthur Adamov, a French writer and playwright with Russian background. The objective of the present study is to focus on the subjective aspect of Adamov's plays and autobiographical texts. The first part of the study tries to highlight the subjective side of the Adamovian writings (discourse). It mainly shows the difference between spontaneous subjectivity and framed subjectivity, through the study of Adamov's L'Aveu (The Consent), La Parodie (Parody), and Ping-Pong. The second part starts with a chapter studying “the Other” in the world (environment / imagination) of the playwright. An “Other” who is divided into several facets. Then we analyze two representative Adamovian plays: Paolo Paoli and Le Printemps 71 (Spring 71). The third part investigates the ground of the duality; several dualities are revealed around the Adamov (ian) Man. The duality between the subjective and the objective is analyzed through Off limits and Si l'été revenait (If the Summer Returned). This last part is the place of meeting between the Ego, the Other and the World in works of Adamov
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Weber, Andreas. "Isolierte Adatome als radioaktive Sonden auf Fe-, Co-, Ni- und Pd-Oberflächen." [S.l. : s.n.], 2001. http://www.diss.fu-berlin.de/2002/34/index.html.
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Simpson, Fiona. "A novel adaptor-related protein complex." Thesis, University of Cambridge, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.627082.
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Medigeshi, Ramarao Guruprasad. "Role of adaptor proteins in MPR sorting." Doctoral thesis, [S.l.] : [s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=968463282.
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Kowanetz, Katarzyna. "Adaptor Proteins in Regulation of Receptor Endocytosis." Doctoral thesis, Uppsala University, Ludwig Institute for Cancer Research, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-4477.
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Ligand-induced endocytosis of receptor tyrosine kinases (RTKs) is a dynamic process governed by numerous protein-protein and protein-lipid interactions. This is a major mechanism of signal termination and is also frequently impaired in cancer. The Cbl family of ubiquitin ligases has been shown to play a key role in downregulation of RTKs, by directing their ligand-induced ubiquitination and subsequent lysosomal degradation. My thesis work has led to the identification of novel, ubiquitin-ligase independent, functions of Cbl in receptor endocytosis. We demonstrated that the adaptor protein CIN85 links Cbl with epidermal growth factor receptor (EGFR) internalization. The three SH3 domains of CIN85 interact with Cbl/Cbl-b in a phosphotyrosine dependent manner, whereas its proline-rich region constitutively binds endophilins, known regulators of plasma membrane invagination. The SH3 domains of CIN85 recognize an atypical proline-arginine (PxxxPR) motif present in Cbl and Cbl-b. Moreover, we showed that numerous endocytic regulatory proteins, among them ASAP1 and Dab2, interact with CIN85 via their PxxxPR motifs. The SH3 domains of CIN85 are able to cluster and exchange its effectors at subsequent stages of EGFR endocytosis, thus participating in the control of receptor internalization, recycling and degradation in the lysosome. We proposed that CIN85 functions as a scaffold molecule implicated in control of multiple steps in downregulation of RTKs.
Furthermore, we identified two novel Cbl- and ubiquitin-interacting adaptor proteins named Sts-1 and Sts-2 (Suppressors of T-cell receptor signaling). Ligand-induced and Cbl-mediated recruitment of Sts-1/Sts-2 into activated EGFR complexes led to inhibition of receptor internalization and subsequent block of receptor degradation followed by prolonged mitogenic signaling pathways. Our results indicate that Sts-1 and Sts-2 represent a new class of negative regulators of Cbl functions in receptor endocytosis.
In conclusion, this thesis describes novel mechanisms by which Cbl, coupled to its effectors, orchestrates trafficking of RTKs. Detailed understanding of how these processes are controlled under physiological as well as under pathological conditions may be important for future therapeutic approaches.
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Lee, Kevin Sung-ho. "Kernel-adaptor interface testing of Project Timeliner." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/49939.
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Watson, Peter James. "Structural and functional studies on adaptor complexes." Thesis, University of Cambridge, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.615311.
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Ghosh, R. "Interactions of SH3 domains in adaptor proteins." Thesis, University College London (University of London), 2011. http://discovery.ucl.ac.uk/1331882/.
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This thesis explores the interactions between adaptor proteins containing Src homology domain 3 (SH3) domains and their potential binding partners. Biochemical, biophysical and in vivo studies were used to investigate the structure, function and dynamics of two SH3-containing adaptors CIN85 and Grb2 in apo and ligand bound states. The project aimed to understand the role of CIN85 and Grb2 as key modulators in signalling cascades and the significance of their interactions with other proteins at the physiological level. The interaction between CIN85 and Cbl/Cbl peptides was investigated. The global architecture and dynamics of CIN85 in apo and Cbl bound states were reported for the first time. NMR studies reported that all three SH3 domains of CIN85 binds to Cbl derived peptides in CIN85ABC, however the interaction have a complex mechanism due to existence of complex dynamics between the SH3 domains and linker regions. However, the study identifies that the SH3 domains in CIN85 works in cooperation with each other with the linkers contributing towards the dynamics and global conformation of CIN85 in the presence and absence of Cbl, which is yet to be understood. The interaction between CIN85 and ubiquitin was investigated by in vitro and in vivo approaches. Ubiquitin binds to all three isolated SH3 domains of CIN85 with diverse affinities in vitro. However the complex between CIN85ABC and ubiquitin was weak and physiologically insignificant. No interactions were observed in cell studies between CIN85ABC and CIN85FL with ubiquitin. Finally, the complex between Grb2 SH3C domain with FGF receptor 2 peptide shows a novel mode of interaction investigated using NMR and docking studies. This work shows that SH3-adaptors have discrete preference for ligands and cannot be generalised as linkers in signalling cascades. Each SH3 domain in adaptors displays their function and subtle regulatory character that is interwoven with their structure and dynamics.
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Märkl, Junji Tobias [Verfasser], and W. [Akademischer Betreuer] Wulfhekel. "Investigation of Magnetic Adatoms with Scanning Tunneling Techniques / Junji Tobias Märkl. Betreuer: W. Wulfhekel." Karlsruhe : KIT-Bibliothek, 2015. http://d-nb.info/1073939936/34.
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Kloppsteck, Jan Patrik. "Structural and functional studies of p97 adaptor interactions." Thesis, Imperial College London, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.539279.
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Peden, Andrew Alexander. "Characterisation of the AP-3 adaptor-like complex." Thesis, University of Cambridge, 2000. https://www.repository.cam.ac.uk/handle/1810/243433.
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Clathrin coated vesicles were the first type of coated vesicle to be characterised. The coat consists of two components, clathrin and adaptor (or AP) complexes, the AP-1 complex is associated with the clathrin coated vesicles that bud from the TGN and the AP-2 complex is associated with the clathrin coated vesicles that bud from the plasma membrane. A new type of adaptor-like complex was discovered in our laboratory and was published in 1996. The complex has been shown to consist of two known proteins, beta3B and mu3B, and two unknown proteins of 160kD and 22kD. Unlike the conventional adaptor complexes this complex is not associated with clathrin. The aim of this thesis was to complete the characterisation of the adaptor-like complex and to establish its function. My studies have shown that, the adaptor-like complex consist of an alpha/gamma like subunit, delta, a beta subunit (beta3A/B), a mu subunit (mu3A/B) and a sigma subunit (sigma3A/B). We named the adaptor-like complexAP-3, by analogy with the AP-1 and AP-2 complexes. The AP-3 complex is localised to perinuclear and more peripheral membranes in non-neuronal cells, with little overlap with endocytic markers. The beta subunit of the AP-3 complex is the major target for phosphorylation. Analysis of mice with mutations in the beta3A subunit, and in the delta subunit of the AP-3 complex, have revealed that the beta subunit is required for the stability of the mu subunit and that the delta subunit is essential for the stability of the whole complex. Further analysis of the mutant mice indicated that the mice lack significant levels of functional AP-3 complex. Studies on fibroblasts generated from these mice revealed that the AP-3 complex plays a role in the trafficking of LAMPI to lysosomes.
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Pearce, Andrew C. "The role of adaptor proteins in platelet activation." Thesis, University of Oxford, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.410670.
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Lee, Ju-Hyun. "The X11 neuronal adaptor proteins and Alzheimer's disease." Thesis, King's College London (University of London), 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.409120.
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Horiuchi, Junjiro. "Characterization of the ADA/GCN5 transcriptional adaptor complex." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/46071.
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Strauss, Johann. "Development of the MINITEL peripheral port adaptor (MPPA)." Thesis, Cape Technikon, 1992. http://hdl.handle.net/20.500.11838/1160.
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Thesis (M.Diploma in Electrical Engineering)--Cape Technikon, 1992This thesis describes how an adaptor board was developed to enable serial devices, such as modems and serial printers operating on RS-232 signals, to be used in conjunction with the MINITEL terminal. Furthermore it enables parallel Centronix interfaces to be Used in conjunction with the MINITEL terminal. The revolutionary 87C751 microprocessor was fully researched, and implemented in the project. Two marketable products emerged during the course of the project: • 1. The 8031-processor solution 2. The 87C751-processor solution
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Brannon, Mary Katherine. "Binding properties of adaptor proteins Tollip and Tom1." Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/73814.
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Adaptor proteins, like Tollip and Tom1, facilitate cellular cargo sorting through their ubiquitin-binding domains. Tollip and Tom1 bind to each other through their TBD and GAT domains, respectively, whereas Tollip interacts with phosphatidylinositol-3-phosphate (PtdIns(3)P)-containing endosomal membranes. Tom1 and Tollip interaction and association with endosomes is proposed to be involved in the lysosomal degradation of polyubiquitinated cargo. Through cellular, biochemical, and biophysical techniques, we have further characterized the association of Tom1 with Tollip. Mutations in the binding interface of the Tom1 GAT and Tollip TBD complex leads to a subcellular mis-localization of both proteins, indicating that Tom1 may serve to direct Tollip to specific cellular pathways. It was determined that Tom1 inhibits the binding of Tollip to PtdIns(3)P and inhibition was reversed when mutations in the binding interface of the Tom1 GAT and Tollip TBD were present. Furthermore, it was established that, upon the binding of Tollip TBD to Tom1 GAT, ubiquitin is inhibited from binding to Tom1 GAT. It was also demonstrated that Tom1 GAT, but not Tollip TBD, can weakly bind to PtdIns(3)P. Consequently, we propose that association of Tom1 may serve to direct Tollip for involvement in specific cell signaling pathways. Gaining insight into the function of Tom1 and Tollip may lead to their use as therapeutic targets for increasing the efficiency of cargo trafficking and also for patients recovering from various cardiac injuries.Master of Science
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Beauparlant, Stephen Lewis. "Functional characterization of the p97 adaptor protein UBXD1." Diss., Temple University Libraries, 2011. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/213118.
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Molecular Biology and GeneticsPh.D.
p97 is a member of the AAA family of proteins (ATPase Associated with various cellular Activities). It is a highly conserved and abundant protein and functions in numerous ubiquitin-mediated processes including ERAD. Endoplasmic Reticulum Associated Degradation is the process by which misfolded/ubiquitinated proteins translocate out of the ER and migrate to the proteasome for degradation. p97 maintains substrate misfolding and mediates its exit from the ER and trafficking to the 26S proteasome. It also plays important roles in protein trafficking, the cell-cycle, apoptosis and homeotypic Golgi Apparatus and Endoplasmic Reticulum membrane fusion after mitosis. In addition, p97 plays a role in the aggresome-autophagy degradation pathway, which handles the ubiquitin-mediated destruction of aggregate-prone, misfolded, cytosolic proteins. p97 mutation is the causative alteration in the disorder, IBMPFD, which is marked by defects in autophagy. This broad diversity of function is mediated through p97's interaction with a large group of adaptor proteins. Many of these adaptors harbor both p97 interaction motifs and ubiquitin association domains. However, more than half of known p97 adaptors do not. Their function is largely unknown. UBXD1 is one known adaptor for p97 that does not have a ubiquitin association domain (UBA), and has been shown to have decreased interaction with IBMPFD mutant p97R155H and p97A232E. Recently, it has been suggested to perform a role in protein trafficking, specifically in monoubiquitinated caveolin-1 internalization and trafficking to the endosome. A novel high abundance UBXD1 interacting partner has been identified via solution-based mass spectrometric analyses. ERGIC-53, the namesake of the ER-Golgi Intermediate Compartment, has been shown to be involved in bi-directional trafficking between the ER and Golgi. The association between UBXD1 and ERGIC-53 is unique among UBX family members. Deletional analysis has shown that unlike p97, the ERGIC-53-UBXD1 interaction takes place in the extreme amino terminus of UBXD1, (within the first 10 amino acids) which is predicted by computer modeling to form a hydrophobic binding pocket. Further site-directed mutagenesis work has clearly shown four amino acids (3 highly hydrophobic) are crucial for maintaining this interaction. They have been modeled to form a conserved alpha-helix. ßCOPI, a primary member of the COPI coatomer complex which is involved in protectively coating ERGIC-53 positive vesicles, is also thought to be involved with the ERGIC-53-UBXD1-p97 pathway. ßCOPI has been identified as a UBXD1-independent interactor with p97. Modest UBXD1 over- expression using a ponasterone inducible system has shown that UBXD1 modulates ERGIC-53 localization. Additionally, a functional link between UBXD1, p97 and ERGIC-53 in autophagy has been discovered through the use of a highly efficient, miR30-based, inducible knockdown system. Upon individual knockdown of UBXD1, p97 and ERGIC-53, autophagic markers p62 and LC3-II accumulate at relatively high levels in normal culture conditions, strongly suggesting a role in mediating basal autophagy. However, when placed under starvation conditions, autophagy progresses and p62 is degraded. It is speculated from these studies that a p97/UBXD1 complex plays a role in regulating the trafficking of ERGIC-53 positive vesicles and this activity plays an important role in autophagy.
Temple University--Theses
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Burget, Josef. "Studie rekonstrukce železničních stanic Adamov a Rájec-Jestřebí." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2012. http://www.nusl.cz/ntk/nusl-225554.
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The aim of the diploma thesis is the reconstruction of Adamov and Rajec-Jestrebi railway stations in order to safety and track capacity of the railway section Brno – Skalice nad Svitavou increasing. The right side of Brno station head end track number 4 are designed in the Adamov railway station. The three platform edges (3x170m) are designed. The safety conditions for the movement of persons with reduced mobility are ensured. Four drive-through traffic tracks and Blansko station head are kept. New substructure and drainage of the track number 4 are designed.
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Favero, Roberta <1992>. "Quasi adatta. Un’ emarginata di prestigio nella letteratura." Master's Degree Thesis, Università Ca' Foscari Venezia, 2017. http://hdl.handle.net/10579/11493.
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La tesi si propone di indagare quale sia oggi il valore e la funzione sociale attribuita alla letteratura per l’infanzia. Una prima parte è dedicata all’illustrazione delle problematiche riscontrate nel processo di definizione di “letteratura per l’infanzia” e delle motivazioni storiche e sociali che hanno portato alla sua nascita. Una seconda parte intende analizzare e confrontare alcune opere del passato e del presente per capire cosa sia cambiato. Infine l’attenzione viene rivolta alla figura del giovane lettore, senza il quale non esisterebbe questa particolare letteratura.
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Turco, M. Y. "FUNCTIONAL CHARACTERISATION OF THE ADAPTOR PROTEIN SHCD/RALP." Doctoral thesis, Università degli Studi di Milano, 2011. http://hdl.handle.net/2434/155509.
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Development requires the strict coordination of signalling pathways driving proliferation, differentiation and migration. Adaptor proteins play an important role in the regulation of specific signalling pathways by linking activated cell-surface receptors to their downstream intracellular targets and mediating crosstalk mechanisms between pathways. ShcD/RaLP, the latest identified member of the Shc family of adaptor proteins showed a unique expression pattern from the other members of the family. It is expressed early during embryogenesis in the pluripotent epiblast and is re-expressed in the developing central and peripheral nervous system and its expression is confined to the brain in the adult. In the pathological context, RaLP is expressed in melanomas and its expression level correlates with disease progression. The physiological role of this protein is still largely uncharacterised. The aim of this PhD project was to characterise the function of RaLP and to understand how this family of adaptor proteins have evolved to modulate distinct signal transduction within different cell types. This could also provide insight on how its deregulation could contribute to pathogenesis.
RaLP knockout (KO) and heterozygote (HT) embryonic stem cells (ESCs) were used as the in vitro model system to dissect the role and signalling pathway of RaLP in development. We found that RaLP expression was recapitulated in vitro as in vivo as it was tightly regulated during the formation of the epiblast in several differentiation programs and then re-expressed when neuronal commitment initiated. Using the recent protocol that allows the transition of pluripotent ESCs to another pluripotent stem cell type, epiblast stem cells (EpiSCs), we specifically investigated the role of RaLP in the establishment of this cell identity. We found that the genetic deletion of RaLP resulted in an impairment of the establishment and maintenance of EpiSCs due to defective proliferation capacity upon differentiation. Furthermore, we have also described for the first time, the emergence of Cdx2 expressing cells during ESC commitment to EpiSC fate and we observed that the absence of RaLP results in an enrichment of this population and enhanced levels of MAPK/Erk1/2 activation. Our data suggests that RaLP plays an important role in the switch of key pathway/s involved in determining EpiSC identity and that the absence of RaLP perturbs the commitment process.
RaLP is also implicated in the differentiation of neural stem cells to neuronal fate. As RaLP is highly expressed in the brain, we sought to understand whether it plays a role in this commitment process. We found that the RaLP KO NSCs showed severe defects in neuronal formation and we are currently analysing our RaLP KO mouse model to obtain a further understanding of the physiological role of RaLP.
In summary, our studies showed that RaLP is involved in EpiSC formation and maintenance as well as neurogenesis, and this dual role is unique for this member of the Shc family, providing an interesting insight into the mechanisms that the cell has evolved to regulate signalling pathways through adaptor proteins in a cell specific manner.
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Nasertorabi, Fariborz. "Biochemical and Structural Studies on the Adaptor Protein p130Cas." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-4777.
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Boger, Klaus [Verfasser]. "Streuung heisser Elektronen an Adatomen auf Metalloberflächen / Klaus Boger." Aachen : Shaker, 2004. http://d-nb.info/1172615950/34.
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Standen, Claire. "Molecular studies of the Fe65 and X11 adaptor proteins." Thesis, King's College London (University of London), 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.401885.
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Rudge, Rachel Emma. "Functional studies of the adaptor-like complex AP-3." Thesis, University of Cambridge, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.620386.
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Wiseman, Katherine. "Characterisation of a new p97 adaptor in genome stability." Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:24e23965-ac0b-4fd9-8928-990df307b52f.
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Cells are subjected to constant genotoxic stress arising from both endogenous and exogenous sources which can drive the development of a wide range of diseases, especially cancers. Therefore, repair of these lesions is essential to maintain genomic stability and health. The DNA damage response is a key aspect of this process and requires the temporal and spatial regulation of many different factors to orchestrate the repair process. This requires the action of the AAA ATPase p97 which acts as a molecular segregase in order to facilitate the turnover of proteins on chromatin. This is also a crucial process to prevent the collision of DNA replication and transcription machinery with DNA bound proteins and DNA structures. These processes require the action of p97 cofactors which direct p97 to specific substrates and biological functions. The role of p97 and its cofactors in the DNA damage response is beginning to emerge, however there is still much to be investigated. Therefore, this thesis focuses on the characterisation of a new p97 adaptor protein discovered during a Mass Spectrometry analysis of the p97 interactome in response to ionising radiation. This adaptor protein, which has been named Ionising Radiation Enhanced VCP Interacting Protein 1, or IREVIP1, is responsible for maintaining genome stability even in unchallenged conditions. IREVIP1 was found to interact directly with p97 via a SHP domain located in the C-terminus of IREVIP1, as well as with Topoisomerases, and is responsible for bridging their interaction. IREVIP1 was observed as being part of the replication fork, and was required to prevent the accumulation of Topoisomerase cleavage complexes. Thus, IREVIP1 could be required to prevent genomic instability arising from collisions with Topoisomerase cleavage complexes and DNA structures arising from excessive DNA torsion. Therefore, this thesis begins to characterise the novel adaptor IREVIP1 and its functions within the cell.
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Sparks-Wallace, Ayrianna, and Shunbin Ning. "The Adaptor Protein p62 Mediates EBV LMP1 Signal Transduction." Digital Commons @ East Tennessee State University, 2020. https://dc.etsu.edu/asrf/2020/presentations/40.
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Epstein-Barr Virus (EBV) is well known to manipulate the host ubiquitin machinery to facilitate its latent persistence and oncogenesis, exemplified by LMP1 signal transduction that activates multiple transcription factors, including NFκB, AP1, and IRF7/IRF4, which promote cell survival and outgrowth, and control immune response and inflammation. It is therefore vital to delineate the detailed mechanisms underlying LMP1 signal transduction for understanding EBV-mediated oncogenesis. p62 (also called SQSTM1, Sequestosome 1) is a ubiquitin sensor and a signal transducing adaptor that interacts with TRAF6 and facilitates the recruitment of ubiquitinated signal intermediators for the activation of NFκB and AP1 in diverse contexts. In turn, p62 is induced by NFκB. However, the interaction between p62 and EBV latency has never been studied. We have recently published interesting and important results, which imply a crucial role for p62 in EBV-mediated oxidative stress. In this study, we further show that p62 is upregulated in EBV latency, with the contribution of LMP1-mediated NFκB and AP1 activities. In turn, p62 participates in LMP1 signal transduction through its interaction with TRAF6, promoting TRAF6 ubiquitination. shRNA-mediated p62 depletion downregulates LMP1-TRAF6 interaction and TRAF6 ubiquitination, and significantly impairs AP1 activity; however, with no detectable effects on NFκB activity. These observations imply that TRAF6-p62 interaction differentiates LMP1 signaling to NFκB and AP1 activation. As a consequence, p62 depletion promotes etoposide-induced apoptosis. These findings identify p62 as a novel player in EBV LMP1 signaling to AP1 activation that is crucial for LMP1-mediated ROS production.