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Vichetti, Rafael Mário [UNESP]. "Síntese dos isótopos do monóxido de carbono no meio interestelar." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/91889.
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De acordo com os resultados observacionais de condensações de nuvens moleculares escuras, grandes variações na razão 13CO/C18O são observadas quando se comparam os resultados obtidos nas condensações situadas dentro da mesma nuvem, bem como de nuvem para nuvem. O valor médio dessa razão na condensação principal de Ophiuchus é inferior a 5. Por outro lado, o valor encontrado nas condensações que estão situadas ao norte de Oph é maior que 10. Grandes diferenças também são encontradas quando se comparam os resultados observacionais de diferentes nuvens escuras, tais como Ophiuchus e Taurus, onde são observados também um decréscimo da razão C18O/C17O com o aumento da densidade. Os processos químicos e físicos que governam essas variações ainda não estão claros. Nesse sentido, o objetivo da presente proposta é analisar a influência do colapso gravitacional de condensações de nuvens moleculares escuras na síntese das moléculas CO, C17O, C18O, 13CO, 13C17O e 13C18O. Tal análise é feita com base em comparações entre modelos que consideram diferentes condições entre si, tais como, tamanho da cadeia química, velocidade de colapso, densidade inicial e processos de congelamento de espécies químicas na superfície de grãos de poeira. Os resultados obtidos mostram que o tamanho da cadeia química tem influência nas razões 13CO/C18O e C18O/C17O, mas não tanto quanto a densidade inicial e a velocidade do colapso. Além disso, o congelamento das espécies químicas nos grãos é mais significativo nos estágios mais avançados da evolução da condensação. Os modelos de condensações escuras que sofrem colapso gravitacional lento e em queda livre reproduzem satisfatoriamente as razões 13CO/C18O e C18O/C17O observadas, o que permite concluir que o colapso gravitacional pode ter um importante efeito nas referidas razões.
According to the observational results of dark molecular clouds condensations, large variations in the ratio 13CO/C18O are observed when comparing the results obtained in the condensations located within the same cloud and cloud to cloud. The average value of this ratio in the main condensation of Ophiuchus is below 5. On the other hand, the value found in the condensations that are located north of Oph is larger than 10. Large differences are also found when comparing the observational results of different dark clouds such as Ophiuchus and Taurus, in which are also found a decrease of the C18O/C17O ratio with increasing density. The chemical and physical processes that govern these variations are still unclear. In this sense, the objective of this proposal is to analyze the influence of the gravitational collapse of centrally condensed clumps of dense molecular gas in the synthesis of the CO, C17O, C18O, 13CO, 13C17O and 13C18O molecules. This analysis is based on comparisons among models that consider different condition, such as, chemical chain, initial density, speed of collapse and freezing processes of the chemical species on the surface of dust grains. The results show that the size of the chemical chain has influence on the 13CO/C18O and C18O/C17O ratios, but they are not as important as the initial density and the speed of the collapse. Furthermore, the freezing of chemical species on the grains occurs at later times of the collapse. The models of a gravitational free-fall collapsing core and of slowly contracting core with higher initial density are consistent with observations. These results indicate that the gravitational collapse of molecular cores can have an important effect in the 13CO/C18O and C18O/C17O ratios.
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Sargant, Robert John. "Molecular dynamics simulations of elongated molecules." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/molecular-dynamics-simulations-of-elongated-molecules(35c31c02-aa1f-4c87-bab9-db81d813974b).html.
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The existence of a thermotropic biaxial nematic liquid crystal phase has been a topic of great interest for almost half a century. Of the various mesogenic shapes suggested as being able to form this phase, theory has suggested that the V-shaped or "bent-core" molecule is one of the most promising candidates. In this thesis we use a simple mesogenic model of a bent-core molecule, constructed from a number of repulsive Weeks-Chandler-Andersen potentials that are assembled into a rigid V shape. Using this model we explore the spontaneous phase behaviour that occurs in a wide array of different systems of mesogens, using molecular dynamics simulations and isotropic initial conditions. We study the relationship between molecular bend angle and phase behavior for molecules constructed from 11 potentials. We find that the phase behaviour splits into two regions, above and below a critical bend angle. Molecules wider than this angle exhibit isotropic, uniaxial nematic and smectic A phases. Narrower molecules show no uniaxially aligned phases, and instead have a clustered phase with short-range ordering and no global alignment director. Increasing system size improves the smectic layering in the wider molecules, but does not affect the global alignment of the narrower molecules. Our model is extended to include the effect of the arm length of the molecule by changing the number of potentials from which the mesogens are constructed. As the molecule is reduced in size, the critical bend angle is seen to move slowly towards more linear molecules, reducing the size of the parameter space in which uniaxial nematic alignment is possible. At 5 beads, all mesophases are seen to disappear and systems remain isotropic. We also study the behaviour of binary mixtures of bent-core molecules, both of differing arm lengths and of differing bend angles. For arm length mixtures, molecules are seen to remain mixed in the isotropic and nematic phases, and phase separate on transition to a smectic phase. In addition, uniaxial nematic phases are induced in systems that have no nematic phase of their own in isolation. For mixtures of different bend angles, systems remain fully mixed in the smectic phases for differences of up to 10 degrees, and beyond this the two components begin to separate at the nematic–smectic transition.
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Barrett, Michael John Sheiko Sergei. "Molecular visualization of individual molecules during flow." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2009. http://dc.lib.unc.edu/u?/etd,2942.
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Thesis (Ph. D.)--University of North Carolina at Chapel Hill, 2010.Title from electronic title page (viewed Jun. 23, 2010). "... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Chemistry." Discipline: Chemistry; Department/School: Chemistry.
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Baker, Joseph Lee. "Steered Molecular Dynamics Simulations of Biological Molecules." Diss., The University of Arizona, 2011. http://hdl.handle.net/10150/205416.
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Molecular dynamics (MD) simulation, which employs an empirical potential energy function to describe the interactions between the atoms in a system, is used to investigate atomistic motions of proteins. However, the timescale of many biological processes exceeds the reach of standard MD due to computational limitations. To circumvent these limitations, steered molecular dynamics (SMD), which applies external forces to the simulated system, can be used.Dynamical properties of the gonococcal type IV pilus (GC-T4P) from the bacteria Neisseria gonorrhoeae are first considered. T4 pili are long, filamentous proteins constructed from a subunit (pilin) found to emanate from the surface of pathogenic bacteria. They can withstand large forces (~100 pN), and are implicated in infection. SMD simulations are performed to study the response of the filament to an applied force. Our simulations reveal that stability of the pilus likely results from hydrophobic contacts between pilin domains buried within the filament core. Along the filament surface, gaps are formed between pilin globular head domains. These gaps reveal an amino acid sequence that was also observed to become exposed in the experimentally stretched filament. We propose two other regions initially hidden in the native filament that might become exposed upon stretching.The multidrug resistance transporter EmrD, found in the inner membrane of Escherichia coli is also the target of our studies. EmrD removes harmful drugs from the bacterial cell. We use MD to explore equilibrium dynamics of the protein, and MD/SMD to study drug interactions and transport along its central cavity. Motions supporting a previously proposed lateral diffusion pathway for substrate from the cytoplasmic membrane leaflet into the central cavity were observed. Additionally, interactions of a few specific residues with CCCP have been identified.Finally, we describe network analysis as an approach for analyzing conformational sampling by MD simulations. We demonstrate for several model systems that networks can be used to visualize both the dominant conformational substates of a trajectory and the connectivity between them. Specifically, we compare the results of various clustering algorithms to the network layouts and show how information from both methods can be combined.
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Wildman, Jack. "Molecular dynamics simulations of conjugated semiconducting molecules." Thesis, Heriot-Watt University, 2017. http://hdl.handle.net/10399/3261.
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In this thesis, we present a study of conformational disorder in conjugated molecules focussed primarily on molecular dynamics (MD) simulation methods. Along with quantum chemical approaches, we develop and utilise MD simulation methods to study the conformational dynamics of polyfluorenes and polythiophenes and the role of conformational disorder on the optical absorption behaviour observed in these molecules. We first report a classical force-field parameterisation scheme for conjugated molecules which defines a density functional theory method of accuracy comparable to high-order ab-initio calculations. In doing so, we illustrate the role of increasing conjugated backbone and alkyl side-chain length on inter-monomer dihedral angle potentials and atomic partial charge distributions. The scheme we develop forms a minimal route to conjugated force-field parameterisation without substantial loss of accuracy. We then present a validation of our force-field parameterisation scheme based on self-consistent measures, such as dihedral angle distributions, and experimental measures, such as persistence lengths, obtained from MD simulations. We have subsequently utilised MD simulations to investigate the interplay of solvent and increasing side-chain lengths, the emergence of conjugation breaks, and the wormlike chain nature of conjugated oligomers. By utilising MD simulation geometries as input for quantum chemical calculations, we have investigated the role of conformational disorder on absorption spectral broadening and the formation of localised excitations. We conclude that conformational broadening is effectively independent of backbone length due to a reduction in the effect of individual dihedral angles with increasing length and also show that excitation localisation occurs as a result of large dihedral angles and molecular asymmetry.
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Schmid, Günter Maximilian. "Dynamical symmetry breaking in molecules and molecular aggregates." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/17393.
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Dean, Delphine Marguerite Denise 1978. "Molecular electromechanics : modeling electrostatic forces between GAG molecules." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/86649.
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Thesis (M.Eng. and S.B.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2001.Includes bibliographical references (p. 81-83).
by Delphine Marguerite Denise Dean.
M.Eng.and S.B.
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Hatter, Nino [Verfasser]. "Fundamental Properties of Molecules on Surfaces : Molecular Switching and Interaction of Magnetic Molecules with Superconductors / Nino Hatter." Berlin : Freie Universität Berlin, 2017. http://d-nb.info/1123572216/34.
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Gatchell, Michael. "Molecular Hole Punching : Impulse Driven Reactions in Molecules and Molecular Clusters." Doctoral thesis, Stockholms universitet, Fysikum, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-129523.
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When molecules are excited by photons or energetic particles, they will cool through the emission of photons, electrons, or by fragmenting. Such processes are often thermal as they occur after the excitation energy has been redistributed across all degrees-of-freedom in the system. Collisions with atoms or ions may also lead to ultrafast fragmentation in Rutherford-like scattering processes, where one or several atoms can literally be knocked out of the molecule by the incoming projectile before the energy can be completely redistributed. The resulting fragmentation pathways can in such knockout processes be very different from those in thermal processes. This thesis covers extensive studies of collisions between ions/atoms and isolated Polycyclic Aromatic Hydrocarbon (PAH) molecules, isolated fullerene molecules, or clusters of these. The high stabilities and distinct fragmentation channels make these types of molecules excellent test cases for characterizing knockout-driven fragmentation and the reactions that these processes can lead to. I will present experimental measurements for a wide range of energies and compare them with my own molecular dynamics simulations and quantum chemical calculations. In this thesis, I present an in-depth study of the role of knockout in the energetic processing of molecules and clusters. The competition between knockout and thermally driven fragmentation is discussed in detail. Knockout-driven fragmentation is shown to result in exotic fragments that are far more reactive than the intact parent molecules or fragments from thermal processes. When such reactive species are formed within molecular clusters efficient molecular growth can take place on sub-picosecond timescales. The cluster environments are crucial here because they protect the newly formed molecules by absorbing excess energy. This is a possible pathway for the growth of large PAHs, fullerenes, and similar carbonaceous complexes found in, for instance, the interstellar medium.At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 1: Submitted.
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Taylor, Jason Matthew 1977. "Controlling molecules with lasers and lasers with molecules." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/38638.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, February 2007.Includes bibliographical references (leaves 140-146).
I investigate quantum control of spin in molecules using shaped ultrafast lasers and the dynamics of those lasers when their cavities are modified to include programmable molecular masks. The ability to control quantum phenomena has had several large successes over the last decade. This field, known as Quantum Control, uses closed loop learning algorithms to shape ultrashort laser pulses in order to produce a desired state or state change. Interesting pulse shapes have been able to break chemical bonds, drive chemical reactions, selectively excite molecular states, and most recently, control photoisomerization in proteins [1, 2, 3]. In this thesis I began by seeking to apply this technique to manipulate spin. In our early work we pursued polarizing electron spins and nuclear spins for NMR Quantum Computation. We studied the electron spin triplet state properties of several molecules. Through this work we recognized that the laser and pulse shaper we were using could be modified to utilize the triplet properties of our molecules. We created a molecular triplet state spatial light modulator (SLM) to be used both outside and inside the laser cavity for ultrafast pulse shaping. The SLM consists of a liquid or thin film sample with a strong triplet state absorption.
(cont.) The molecule is selected to be transparent to the target light before pumping and strongly absorptive when pumped into the triplet state. The sample is exposed to laser light reflected off of a DMD chip to produce a 2D pattern to spatially populate the triplet ground state. This is, to our knowledge, the first triplet state ultrafast pulse shaper and the first all-optical inter-cavity spatial frequency modulator.
by Jason Matthew Taylor.
Ph.D.
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Lindqvist, Lisa Margareta. "The molecular dissection of protein synthesis via small molecules." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=96682.
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Protein synthesis is a highly regulated process and it is vital to life. If the rate of translation is too slow, proteins will not be replaced fast enough causing an imbalance in protein turnover and eventual cell death. On the other hand, if the rate of translation is too fast, it can lead to uncontrolled growth and potential tumorigenesis. The scientific community is now trying to exploit this concept to create novel anticancer therapies using inhibitors of translation. These inhibitors have also been invaluable to dissecting the mechanism of translation.Hippuistanol is an inhibitor of translation initiation which inhibits eIF4A:RNA interaction. Herein I characterize the binding site of hippuristanol on eIF4A and develop hippuristanol-resistant mutants to demonstrate that both helicase activity and eIF4G:eIF4A interaction are absolutely required for eIF4A to function in translation. As well, I utilize this compound to determine that eIF4B, eIF4H, and eIF3a cross-link to RNA in an eIF4A-dependent manner up to 52 nucleotides downstream from cap structure of the mRNA. We also demonstrate that eIF4E only cross-links to RNA within a few nucleotides of the cap structure and is not visible at 12 nucleotides downstream of the cap structure. These results shed light on the positioning of initiation factors within the 5'UTR.Herein I also present that cytotrienin A, an inducer of apoptosis in leukemia cell lines, as a novel inhibitor of translation elongation. The compound inhibits proper eEF1A function and inhibits translocation when aminoacyl-tRNA is loaded onto the ribosome in an eEF1A-dependent fashion. Cytotrienin A also hindered growth in several models of angiogenesis indicating that this compound has potential as an anticancer therapeutic. These results strengthen the idea that inhibitors of translation have great potential as anticancer agents as well as being great tools to dissect the mechanism of protein synthesis.La synthèse protéique ou traduction est un processus hautement régulé et essentiel à la vie. Si le rythme de synthèse protéique est trop lent, les protéines ne sont pas remplacées assez rapidement créant un débalancement du taux de renouvellement protéique ce qui entraîne la mort cellulaire. À l'opposé, si le rythme de synthèse est trop rapide, ceci peut engendrer une croissance cellulaire anarchique et potentiellement initier la tumorigenèse. La communauté scientifique cherche à exploiter ce concept afin de créer de nouvelles thérapies anticancéreuses utilisant des inhibiteurs de la traduction. Ces inhibiteurs sont également des outils inestimables pour disséquer les mécanismes de la traduction.L'hippuristanol est un inhibiteur de la traduction qui bloque l'interaction entre eIF4A er l'ARN. Ici, j'ai caractérisé le site de liaison de l'hippuristanol sur eIF4A et j'ai développé des mutants résistant à l'hippuristanol qui ont servis à démontrer que la fonction d'hélicase et l'interaction eIF4G:eIF4A sont toutes deux requises pour que eIF4A soit fonctionnel dans la traduction. De plus, j'ai utilisé ce composé pour déterminer que eIF4B, eIF4H et eIF3a sont tous liés à l'ARN par chimio-pontage et ces interactions qui peuvent être détectées jusqu'à 52 nucléotides en aval de la coiffe requièrent eIF4A. Nous avons également démontré que l'association de eIF4E à l'ARNm n'est détectée par chimio-pontage qu'avec les quelques nucléotides immédiatement en aval de la coiffe et n'est pas détectable au niveau du douzième nucléotide. Ces résultats ont éclaircis le positionnement des facteurs d'initiation au niveau du 5'NTR.Ici, je démontre également que la cytotriénine A, un inducteur d'apoptose dans les cellules leucémiques, est un nouvel inhibiteur de l'élongation lors de a traduction. Ce composé inhibe le fonctionnement du facteur eEF1A et inhibe l'étape de translocation dépendante de eEF1A qui ensuit le chargement du complexe aminoacyl-tRNA sur le ribosome. Le cytotriène A empêche également la croissance dans plusieurs modèles d'angiogenèse, indiquant que ce composé possède un potentiel comme agent anticancéreux. Ces résultats renforcent l'idée que les inhibiteurs de la traduction possèdent un énorme potentiel en tant qu'agent anticancéreux, ainsi que comme outils afin de décortiquer les mécanismes gouvernant la synthèse protéique.
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Jagatia, Fiona Jennifer. "Excited state interactions between organic molecules and molecular oxygen." Thesis, Keele University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246864.
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Panesar, Kuldeep Singh. "Quantum molecular dynamics of guest molecules in supramolecular complexes." Thesis, University of Nottingham, 2009. http://eprints.nottingham.ac.uk/10741/.
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The quantum motion of guest molecules has been studied in a variety of calixarene host-guest complexes, and in a endohedral fullerene complex. The guest molecules of the calixarene complexes studied each comprise weakly hindered methyl groups, which undergo rotation via quantum tunnelling, even at cryogenic temperatures. The rotational motion of the guest methyl-groups has been studied by making temperature and frequency-dependent measurements of proton T1, using field-cycling NMR, thus revealing the spectral density functions of the magnetic dipole-dipole interaction. Crystallographically inequivalent methyl-group environments have been identified and characterised in p-tert-butylcalix[4]arene(1:1)toluene, p-tert-butylcalix[4]arene(1:1)gamma-picoline and p-isopropylcalix[4]arene(2:1)p-xylene. In many of the calixarene complexes the proton spin-lattice relaxation has been observed to be strongly dependent on the thermal history of the sample. Temperature-dependent measurements of proton T1 in samples of p-tert-butylcalix[4]arene(1:1)toluene with partially deuterated guest molecules reveal a systematic reduction in T1 at low temperatures with increased degree of deuteration. Calixarene and fullerene host-guest complexes have been identified as having a potential application in cryogenic MAS-NMR as cryorelaxor complexes, capable of being attached to a large biomolecule and encouraging proton spin-lattice relaxation. The suitability of the calixarene complexes for use in this capacity has been investigated by measuring the temperature-dependence of proton T1 at low temperatures. The quantised rotational and translational motion of dihydrogen confined within an open-cage fullerene—namely, aza-thio-open-cage-fullerene (ATOCF)—has been revealed by inelastic neutron scattering (INS) measurements. The splitting of excited rotational and translational states, due to the low symmetry of the ellipsoidal fullerene cavity, has been directly measured. Assignment of the peaks observed in the INS spectrum has been aided by analysis of the Q-dependence of excitation bands. The thermodynamics of ortho- and parahydryogen have been investigated via temperature dependence measurements. INS measurements have allowed the anistropic rotational potential experienced by the H2 rotor to be determined.
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Zotti, Linda Angela. "Molecular ordering and STM imaging of functionalized organic molecules." Thesis, University of Liverpool, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.479082.
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Kirsch, Nicole. "Molecular recognition of poorly functionalised molecules with imprinted polymers." Thesis, University of Reading, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325167.
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Roskilly, Stephen. "Molecular field theory of nematics composed of flexible molecules." Thesis, University of Southampton, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.259682.
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Wiles, Alan Andrew. "Redox active molecules with molecular electronics and synthetic applications." Thesis, University of Glasgow, 2013. http://theses.gla.ac.uk/4878/.
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Redox active molecules are ubiquitous to nature and have properties that make them coveted targets for applications in areas of synthesis as well as for the development of materials. This thesis describes the synthesis and characterisation of several flavin donor-acceptor dyads designed around an oligothiophene donor backbone and a flavin acceptor moiety. These show potential applications as optoelectronic materials. It also describes the synthesis of a ferrocene-flavin tetracyanobutadiene super-acceptor compound which showed preliminary evidence of non-linear-optic effects. Finally, a novel method was developed to investigate the redox umpolung activated reactions of vinylferrocene. The vinyl group of vinylferrocene was activated by polarity inversion of ferrocene to ferrocenium and was able to undergo Diels-Alder cycloadditions with cyclobutadiene and furan, as well as, Markovnikov addition of thiols. These reactions were then used to explore the use of vinylferrocene as a redox auxiliary and as a redox active tag in polymers and have the potential to be used in nanoparticles as well as biological systems.
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Symes, Mark D. "Walking molecules." Thesis, University of Edinburgh, 2009. http://hdl.handle.net/1842/3195.
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Inspired by the motor protein kinesin, an ambitious and unprecedented mimic is proposed – a synthetic molecular motor that can walk. This thesis aims to explain the basic principles which define such walking molecules, with reference to both natural and synthetic systems. In light of these tenets, the rational design of the proposed synthetic kinesin analogue will then be expounded. The putative design envisages the use of a series of stimuli-induced binding events to cause a “walker unit” to process along a polypyridyl track in a unidirectional, hand-over-hand fashion. The chemistry behind the stepping mechanisms of both feet of the walker unit will be discussed in detail, along with a complete description of the synthesis of the track and walker unit to date. The future challenges and potential applications of the proposed system will be addressed.
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Kay, Euan R. "Mechanized molecules." Thesis, University of Edinburgh, 2006. http://hdl.handle.net/1842/12333.
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This Thesis describes the use of synthetic chemistry to investigate mechanisms for controlling molecular-level motion. Initially, the principles that all experimental designs for working molecular machines must follow are elucidated; tracing the development of ideas about molecular-level motion from their genesis, to the modern-day contributions of molecular biology and theoretical nonequilibrium statistical physics. In the rest of the Thesis, these theoretical considerations are applied and extended through the construction and operation of molecular machines based on interlocked molecules. Two simple rotaxane-based examples serve to demonstrate the novel concept of ‘compartmentalized’ molecular machines. Correlating chemical, physical and statistical descriptions of these simple devices with their behaviour, reveals the fundamental mechanistic elements that are involved in the operation of any compartmentalized Brownian machine and suggests how these can be combined to create different types of device. This leads to the construction of a [2]catenane that is the first example of a reversible synthetic rotary molecular motor and which operates via an energy ratchet mechanism. Next, a fundamentally different mechanism is investigated through the construction and analysis of a compartmentalized molecular machine that is the first to operate via an information ratchet mechanism. Finally, the classic stimuli-responsive molecular shuttle design serves as an ideal test bed for investigating a new structural series of rotaxane-based molecular machines that are controlled by redox processes and which show promise for operation at surfaces.
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Brooke, Carly. "Synthesis, characterisation and single molecule conductance measurements of organic molecules." Thesis, University of Liverpool, 2012. http://livrepository.liverpool.ac.uk/9397/.
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The use of single molecules to construct electronic devices is an exciting prospect, and one that has long provided a driving force for research in the area of molecular scale electronics. In order for this emerging field to advance a deep understanding of the fundamental mechanisms that govern electron conduction at the molecular level is imperative. Recent developments in areas such as scanning tunnelling microscopy, have facilitated the determination of the electrical properties of single molecules tethered between two metallic contacts. The analysis and potentially tailoring of structure-property relationships is hugely important and could lead to new and unforeseen applications for this emerging field. The work presented herein details two major studies. The first is an investigation of the transport properties of a series of analogous molecules, which consist of a single benzene ring sandwiched between two alkyl chains of varying length. Prior to the work in this thesis one such molecule, and various substituted analogues thereof, had shown behaviour similar to what would be expected of a molecular equivalent of a double tunnelling barrier. The data presented here demonstrates a remarkably low dependence of this system on molecular length; this result contradicts the behaviour expected of a coherent transport mechanism. Moreover, the study of the orbital energies and densities of these molecules provides further evidence of a mechanism of conduction that is very different to that previously suggested for this system. The second study centres around the investigation of the conductance behaviour of 4,4’-bipyridine and some substituted analogues thereof; this study is presented in two parts. The first details attempts to synthesise planar analogues of 4,4’-bipyridine, as well the synthesis and reactivity of novel substituted bipyridines. The second part reports conductance data, electrochemical studies and theoretical calculations of properties of these molecules. The data presented provides new information regarding the relationship between electronic structure and conductance behaviour in this type of system.
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Pounds, Andrew J. "A generalized discrete dynamical search method for locating minimum energy molecular geometries." Diss., Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/27144.
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Eckel, Rainer. "Single molecules and nanocrystals: molecular recognition forces and optomechanical switching." [S.l.] : [s.n.], 2006. http://deposit.ddb.de/cgi-bin/dokserv?idn=978888227.
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Samorí, Paolo. "Self-assembly of conjugated (macro)molecules nanostructures for molecular electronics /." [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=962281530.
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Roberts, Darren Leslie. "Molecular characterisation of the pro-apoptotic molecules APAF1 and Smac." Thesis, University of Leicester, 2001. http://hdl.handle.net/2381/30757.
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Apoptosis is a key process involved in cell number regulation and a range of pathological disorders. It is a highly structured process that removes the cell from the body without damage to surrounding cells. The mitochondria has been shown to play a key role in apoptosis induced by a wide range of stimuli and can trigger the apoptotic pathway by release of apoptogenic factors. One of these factors is cytochrome c, a protein that normally functions in the electron transport chain but upon release it binds to the first mammalian homologue of CED-4, Apoptotic Protease Activating Factor 1 (APAF1) and induces the formation of a large caspase-activating complex. Another protein released from the mitochondria is Smac, a pro-apoptotic protein that functions by antagonising Inhibitor of Apoptosis Protein function. The data presented in this thesis demonstrates the existence of multiple splice forms of both APAF1 and Smac and investigated their roles in the apoptotic pathway. APAF1 forms the large molecular weight complex known as the apoptosome in 293 cells although epitope tagged APAF1 formed an incorrectly formed this complex in the absence of additional stimuli. APAF1 was also found to be cleaved by Caspase-3 during apoptosis and that the resulting 30 kDa fragment is associated with the inactive complex. Data also indicates that caspase-9 recruitment to the apoptosome occurs via interactions between both the CARD and the CED-4 homologous regions of APAF1. The pro-apoptotic protein Smac exists as several forms due to alternative slicing and one of these forms, Smac , is pro-apoptotic even though it lacks the N-terminal Inhibitor of Apoptosis protein binding domain. Smac is localised to the cell cortex and does not redistribute upon induction of apoptosis. These data demonstrate that Smac is able to induce apoptosis independently of Inhibitor of Apoptosis Protein binding. A polyclonal antibody to Smac / Smac was also developed and characterised.
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Stoer, Marcell. "Molecular beam laser Stark spectroscopy of highly vibrationally excited molecules." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ34285.pdf.
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Jenny, Nicolas [Verfasser]. "Synthesis of New Functional Molecules for Molecular Electronics / Nicolas Jenny." München : Verlag Dr. Hut, 2012. http://d-nb.info/1026652278/34.
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Comben, E. R. "The study of small molecules by high resolution molecular spectroscopy." Thesis, University of Oxford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375245.
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Aitken, Craig George. "Electron impact ionisation of molecular clusters and spatially oriented molecules." Thesis, University of Canterbury. Chemistry, 1995. http://hdl.handle.net/10092/7613.
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A pulsed supersonic molecular beam apparatus has been used to determine the appearance energies of the cluster ions (CO₂)n+ (2≤n≤4), (N₂O)n+ (2≤n≤4), (NH₃)nNH⁺₄ (0≤n≤7) and the cluster ion fragments (N₂O.O)⁺ and (N₂O.NO)⁺ by electron impact ionisation. The measured appearance energies were used to estimate cluster ion binding energies and to deduce possible mechanisms for the formation of the cluster fragment ions (N₂O.O)⁺ and (N₂O.NO)⁺.
A discussion is given on the transformation of the molecular beam machine to accommodate the study of electron impact ionisation of spatially oriented molecules. Characterisation of the inhomogeneous electrostatic hexapole field is described. Electron impact ionisation asymmetry results were measured for CH₃Cl, CH₃Br, CF₃Br and CHCl₃ using a quadrupole mass spectrometer and mass insensitive rotatable particle multiplier. Measurement of the asymmetry effect for formation of the molecular ions CH₃Cr, CH₃Br⁺ and the fragment ions CH₃+ from CH₃Cl and CH₃Br, CF₃⁺ from CF₃Br and CHCl₂+ from CHCl₃ are determined and discussed. Each molecule showed a preference for electron impact to occur at the positive end of the molecule. The effect of hexapole voltage and electron energy on the asymmetry effect is also discussed. A simple model is presented for electron impact ionisation at either end of a molecule which accounts qualitatively with the asymmetry results determined.
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Adam, Colin John. "Molecular properties of mesogenic fragments and molecules from first principles." Thesis, University of Edinburgh, 1999. http://hdl.handle.net/1842/10776.
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In order to gain a deeper understanding of the relationship between molecular structure and liquid crystal properties, accurate data is required on single molecule properties of mesogenic fragments and molecules. This thesis applies a pseudopotential plane wave total energy method to calculate molecular properties of prototypical mesogenic fragments and the molecule 4-n-pentyl-4'-cyanobiphenyl (5CB) from first principles. Optimised molecular structures, vibrational properties and torsional potentials are determined and found to compare well with experimental observations and other ab initio investigations. A study is made of the transferability of torsional potentials between mesogenic fragments and 5CB. Also investigated is the conformation-dependence of dipole and quadrupole moments. The strength of the coupling is found to depend sensitively on the molecular structure and the conformation-dependence of quadrupole moments is found to significantly influence inter-molecular interactions. Finally, by combing first principles calculations with an empirical mean field approximation, conformational distributions of the alkyl tail in 5CB are examined.
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Wright, Patricia Ann. "Understanding MS/MS fragmentation pathways of small molecular weight molecules." Thesis, University of Greenwich, 2015. http://gala.gre.ac.uk/18134/.
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Fragmentation of molecules by collision-induced dissociation (CID) is not well-understood, making interpretation of MS/MS spectra difficult and limiting the effectiveness of software tools intended to aid mass spectral interpretation. An approach is required which is tailored to each individual molecule and improves the ‘chemical sense’ of the software. It was hypothesised that the bonds which break during CID of protonated molecules are the bonds which are elongated, and hence weakened, as a result of conformational changes induced by protonation. Bond length changes for a test set of molecules were calculated using quantum chemistry software. Density Functional Theory (DFT) or Austin Model 1 (AM1) or both were used to energy minimise the structures of the neutral molecules and their corresponding protonated molecules (protonated at all possible sites). Bonds which elongated to the greatest extent after protonation were compared to the bonds which were found to cleave to give the product ions in the CID spectra of these compounds. Quantum chemistry modelling was also applied to the deprotonated molecules. AM1 calculated bond lengths were found to be similar to those generated by DFT and have the advantage of being rapidly obtained. All the polarised bonds which cleaved were calculated to elongate significantly, thus achieving a 100% success rate in the prediction of bond cleavage as a result of protonation on a heteroatom. The proton is mobile across the molecule, leading to fragmentation when the proton reaches a site where it causes significant bond elongation, provided the molecule has sufficient internal energy. Cleavage of carbon-carbon bonds was not predicted. The success rate for predicting bond cleavage in deprotonated molecules was 48%, suggesting this approach cannot be applied reliably for these anions. AM1 calculated bond length change acts as a descriptor for predicting polarised bond cleavage in protonated pseudo-molecular ions having the potential to be incorporated in mass spectral interpretive software to increase the accuracy of prediction of CID spectra.
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Morisawa, Yusuke. "Spectroscopic study of some chemically significant molecules in molecular clouds." 京都大学 (Kyoto University), 2005. http://hdl.handle.net/2433/144599.
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Tanjaroon, Chakree. "Rotational spectra and molecular structures of organometallic and organic molecules." Diss., The University of Arizona, 2004. http://hdl.handle.net/10150/280570.
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Understanding the nature of chemical bonds constitutes a major theme of this thesis. This thesis investigates the gas phase rotational spectra, electronic charge distributions and molecular structures of organometallic and organic molecules, using high-resolution pulsed beam Fourier transform microwave spectroscopy (PBFTMS) and computational methods. High-resolution rotational spectra and structural parameters were obtained for the following organometallic molecules in the singlet electronic state, including three symmetric and five asymmetric top complexes: C₅H₅Nb(CO)₄, CH₃Mn(CO)₅, MnRe(CO)₁₀, C₅H₅Mo(CO)₃H, C₅H₅W(CO)₃H, C₅H₅NiC₃H₅, C5H₄(CH₃)FeC₅H₅ and (C₅H₄(CH₃))₂Fe. High-resolution rotational spectra and structural parameters were obtained for three organic molecules in the singlet electronic state: ortho-benzyne (C₆H₄) and the keto-enol tautomers, 2-hydroxypyridine and 2-pyridone (C₅H₅NO). In addition to the tautomeric forms, pure rotational spectra of the H-bonded dimer, 2-hydroxypyridine:2-pyridinone, were also obtained. These detailed spectral investigations yielded novel and useful information about the molecular properties of these molecules. Primarily, these results provided information regarding chemical bonding, vibrational ground state structures, structural isomers, conformational behavior, metal-hydrogen bonding and electronic charge distributions. Density functional theory (DFT) and ab-initio calculations were carried out in conjunction with the experiments, providing additional insights into further understanding the equilibrium structures, structural isomers and the electric field gradient distributions for these molecules.
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Spencer, Peter D. "Examining claims of long-range molecular order in water molecules." Thesis, Queensland University of Technology, 2018. https://eprints.qut.edu.au/121427/1/__qut.edu.au_Documents_StaffHome_StaffGroupH%24_halla_Desktop_Peter%20Spencer%20Thesis.pdf.
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This project addressed the uncertainty of the properties of water at specific surfaces.
New experimental evidence enabled the reinterpretation of previously reported findings and demonstrates the importance of further research in this area.
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Martínez, Rodríguez Luis. "Molecule and catalyst design for recognition and activation of small molecules." Doctoral thesis, Universitat Rovira i Virgili, 2016. http://hdl.handle.net/10803/398693.
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Strand, Joanna. "Affibody Molecules for PET Imaging." Doctoral thesis, Uppsala universitet, Institutionen för immunologi, genetik och patologi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-259410.
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Optimization of Affibody molecules would allow for high contrast imaging of cancer associated surface receptors using molecular imaging. The primary aim of the thesis was to develop Affibody-based PET imaging agents to provide the highest possible sensitivity of RTK detection in vivo. The thesis evaluates the effect of radiolabelling chemistry on biodistribution and targeting properties of Affibody molecules directed against HER2 and PDGFRβ. The thesis is based on five published papers (I-V). Paper I. The targeting properties of maleimido derivatives of DOTA and NODAGA for site-specific labelling of a recombinant HER2-binding Affibody molecule radiolabelled with 68Ga were compared in vivo. Favourable in vivo properties were seen for the Affibody molecule with the combination of 68Ga with NODAGA. Paper II. The aim was to compare the biodistribution of 68Ga- and 111In-labelled HER2-targeting Affibody molecules containing DOTA, NOTA and NODAGA at the N-terminus. This paper also demonstrated favourable in vivo properties for Affibody molecules in combination with 68Ga and NODAGA placed on the N-terminus. Paper III. The influence of chelator positioning on the synthetic anti-HER2 affibody molecule labelled with 68Ga was investigated. The chelator DOTA was conjugated either at the N-terminus, the middle of helix-3 or at the C-terminus of the Affibody molecules. The N-terminus placement provided the highest tumour uptake and tumour-to-organ ratios. Paper IV. The aim of this study was to evaluate if the 68Ga labelled PDGFRβ-targeting Affibody would provide an imaging agent suitable for PDGFRβ visualization using PET. The 68Ga labelled conjugate provided high-contrast imaging of PDGFRβ-expressing tumours in vivo using microPET as early as 2h after injection. Paper V. This paper investigated if the replacement of IHPEM with IPEM as a linker molecule for radioiodination of Affibody molecules would reduce renal retention of radioactivity. Results showed that the use of the more lipophilic linker IPEM reduced the renal radioactivity retention for radioiodinated Affibody molecules. In conclusion, this thesis clearly demonstrates that the labelling strategy is of great importance with a substantial influence on the targeting properties of Affibody molecules and should be taken under serious considerations when developing new imaging agents.
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Gottschalk, Thomas. "Switchable container molecules /." Zürich : ETH, 2008. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=18067.
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Howell, Brian. "Signal transducing molecules." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=39347.
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The involvement of protein phosphorylation and gene regulation in signal transduction pathways are examined. In particular the role of the novel STY kinase in signal transduction networks is suggested, followed by a study of the liver-specific and inducible expression of the carbamyl phosphate synthetase I (CPSI) gene. In a screen of an embryonal carcinoma (EC) cell cDNA expression library with an antibody to phosphotyrosine, the STY kinase was identified. STY is represented by a single 1.8 kb transcript in undifferentiated P19 cells. During differentiation of these cells, mRNAs of 3.2 and 5.6 are induced and persist to adulthood. Sequence analysis of the STY kinase revealed a catalytic domain homologous to kinases with serine/threonine phosphorylating specificity especially those involved in cell-cycle control, such as the FUS3 gene. Biochemical analysis of recombinant STY synthesized in bacteria or in vitro indicated a serine-, threonine-, and tyrosine-phosphorylating capability, suggesting that it belongs to a previously unappreciated family of kinases.The promoter region of the liver specific, glucocorticoid and cAMP inducible gene, CPSI was analyzed for transcriptional activity. Sequences extending from the in vivo start site of CPSI gene to $-$1200 bp, were shown to support in vitro transcription with liver nuclear extracts. A region proximal to transcription initiation, from $-$104 to $-$124 was shown to specifically interact with the abundant liver nuclear factor C/EBP. Double stranded oligonucleotides corresponding this cis element abolishes in vitro transcription reactions in a competitive manner. The C/EBP and related factors, LAP and LIP, interaction with CPSI promoter elements has implications in the developmental, liver-specific, as well as the inducible aspects of CPSI gene expression.
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Ferguson, Jayne Louise. "Colossal Aromatic Molecules." Thesis, University of Canterbury. Chemistry, 2013. http://hdl.handle.net/10092/8108.
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This thesis describes the preparation of a series of compounds containing π-excessive, five-membered, heterocyclic rings with peripheral aryl substituents, designed to investigate their oxidative cyclodehydrogenation and/or photocyclisation to form curved, fused aromatic systems with a heterocyclic atom at the core of the compound. The ability of these compounds to undergo oxidative cyclodehydrogenation was investigated using a range of conditions, including the use of Lewis acidic transition metals, organic reagents and light as catalysts to carry out the desired carbon-carbon bond forming reactions. Two backbone linked 2,2’-biimidazole ligands were prepared to investigate their coordination chemistry with a range of different metal ions and counter ions.
Two families of model compounds, including ten previously unreported compounds, were prepared and subjected to various conditions for oxidative cyclodehydrogenation and photocyclisation resulting in the isolation of compounds with one carbon-carbon bond formed between the peripheral aryl rings in the same position on the heterocyclic ring, nineteen previously unreported compounds were isolated. Additionally, in one case oxidative cyclodehydrogenation resulted in the formation of two carbon-carbon bonds, producing a highly strained aromatic compound containing a heterocyclic ring. Photocyclisation of one family of compounds resulted in the formation of a different heterocyclic core dependent upon the substituent on the nitrogen atom. Five pentaarylpyrrole compounds, three of which were previously unreported, were also prepared after the exploration of various synthetic routes towards the pentaarylpyrrole motif. Photocyclisation also resulted in the formation of one carbon-carbon bond. The compounds resulting from oxidative cyclodehydrogenation and photocyclisation were characterised by NMR spectroscopy, UV/vis spectroscopy and fluorometry, where possible X-ray crystallography was also used.
The coordination chemistry of backbone linked 2,2’-biimidazole ligands to various metal ions could be controlled by the length of the backbone linker. The ethyl linked 2,2’-biimidazole ligand formed bridging and monodentate coordination compounds with various metal ions, the metallosupramolecular assemblies produced with silver ions could be controlled by the anion present. Discrete coordination complexes were usually formed, but in two cases metallopolymers were produced. The propyl linked 2,2’-biimidazole ligand formed exclusively discrete, chelating complexes with copper (II) metal ions. Eighteen coordination complexes were prepared during the course of this study characterized by X-ray crystallography, and NMR spectroscopy where appropriate.
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Graham, Robert Leslie James. "Snake venom molecules." Thesis, University of Ulster, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.398964.
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Lewis, R. K. "Synthetic receptor molecules." Thesis, University of Liverpool, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356259.
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Barckholtz, Timothy Andrew. "Fragments of molecules /." The Ohio State University, 1998. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487952208108668.
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Newell, Catherine A. "INELASTIC COLLISIONS IN COLD DIPOLAR GASES." UKnowledge, 2010. http://uknowledge.uky.edu/gradschool_diss/30.
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Inelastic collisions between dipolar molecules, assumed to be trapped in a static electric field at cold (> 10−3K) temperatures, are investigated and compared with elastic collisions. For molecules with a Λ-doublet energy-level structure, a dipole moment arises because of the existence of two nearly degenerate states of opposite parity, and the collision of two such dipoles can be solved entirely analytically in the energy range of interest. Cross sections and rate constants are found to satisfy simple, universal formulas. In contrast, for molecules in a Σ electronic ground state, the static electric field induces a dipole moment in one of three rotational sublevels. Collisions between two rotor dipoles are calculated numerically; the results scale simply with molecule mass, rotational constant, dipole moment, and field strength.
It might be expected that any particles interacting only under the influence of the dipole-dipole interaction would show similar behavior; however, the most important and general result of this research is that at cold temperatures inelastic rate constants and cross sections for dipoles depend strongly upon the internal structure of the molecules. The most prominent difference between the Λ-doublet and rotor molecules is variation of the inelastic cross section with applied field strength. For Λ-doublet dipoles, cross sections decrease with increasing field strength. For rotor dipoles, cross sections increase proportionally with the square of field strength. Furthermore, the rate constants of the two types of molecules depend very differently on the angular orientations of the dipoles in the electric field.
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Francis, Simon George. "Microwave spectroscopy of metal-containing molecules and molecules of atmospheric interest." Thesis, University of Bristol, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.508090.
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Swann, Andrew Thomas. "Characterization of polymer-supported homogeneous catalysts by molecular modeling." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26702.
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Thesis (Ph.D)--Chemical Engineering, Georgia Institute of Technology, 2009.Committee Chair: Ludovice, Pete; Committee Member: Grover, Martha; Committee Member: Jones, Christopher; Committee Member: Realff, Matthew; Committee Member: Sherrill, David. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Gromova, O. V. "High resolution molecular spectroscopy of the sulfur-containing XY2 type molecules." Phd thesis, Université de Bourgogne, 2010. http://tel.archives-ouvertes.fr/tel-00534459.
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Dans cette these, nous avons effectue l'analyse des spectres d'absorption a haute resolution de H2S, D2S, HDS et SO2 enregistres pour la premiere fois ou avec une meilleure precision experimentale que les spectres anterieurs. Nous avons developpe une methode originale de "global ftting" qui nous a permis l'analyse de 22 bandes vibrationnelles soit un total de 9700 transitions rovibrationnelles pour la molecule de D2S. Nous avons applique cette meme methode a des molecules de symmetrie Cs, en particulier tout le spectre rovibrationnel de la molecule HDS a ete analyse. La methode SPGF est appliquee aux molecules triatomiques H2S, D2S, HDS. Une procedure originale permettant l'identication des bandes tres peu intenses a ete mise au point pour la premiere fois et appliquee aux bandes chaudes de la molecule SO2. Le formalisme U(p+1) est adapte aux molecules triatomiques non lineaires de symmetrie C2v et les parametres d'un Hamiltonien vibrationnel sont determines dans le cas de la molecule D2S.
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Rohatgi, Priyanka. "Engineering Protein Molecular Switches To Regulate Gene Expression with Small Molecules." Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/19852.
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Small molecule dependent molecular switches that control gene expression are important tool in understanding biological cellular processes and for regulating gene therapy. Nuclear receptors are ligand activated transcription factors that have been engineered to selectively respond to synthetic ligands and used as regulators of gene expression. In this work the retinoid X receptor (RXR), has been used to develop an inducible molecular switch with a near drug like compound LG335. Three RXR variants (Q275C; I310M; F313I), (I268A; I310A; F313A; L436F), (I268V; A272V; I310M; F313S; L436M) were created via site-directed mutagenesis and a structure based approach, such that they preferentially bind to the synthetic ligand LG335 and not its natural ligand, 9-cis retinoic acid. These variants show reverse ligand specificity as designed and have an EC50 for LG335 of 80 nM, 30 nM, 180 nM, respectively. The ligand binding domains of the RXR variants were fused to a yeast transcription factor Gal4 DNA binding domain. This modified chimeric fusion protein showed reverse response element specificity as designed and recognized the Gal4 response element instead of the RXR response element. The modified RXR protein did not heterodimerize with wild type RXR or with other nuclear receptor such as retinoic acid receptor. These RXR-based molecular switches were tested in retroviral vectors using firefly luciferase and green fluorescence protein and they maintain their inducible behavior with LG335. These experiments demonstrate the orthogonality of RXR variants and their possible use in regulating gene therapy.
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Hofström, Camilla. "Engineering of Affibody molecules for Radionuclide Molecular Imaging and Intracellular Targeting." Doctoral thesis, KTH, Molekylär Bioteknologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-116884.
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Affibody molecules are small (7 kDa) affinity proteins of non-immunoglobulin origin that have been generated to specifically interact with a large number of clinically important molecular targets. In this thesis, Affibody molecules have been employed as tracers for radionuclide molecular imaging of HER2- and IGF-1R-expressing tumors, paper I-IV, and for surface knock-down of EGFR, paper V. In paper I, a tag with the amino acid sequence HEHEHE was fused to the N-terminus of a HER2-specific Affibody molecule, (ZHER2), and was shown to enable facile IMAC purification and efficient tri-carbonyl 99mTc-labeling. In vivo evaluation of radioactivity uptake in different organs showed an improved biodistribution, including a 10-fold lower radioactivity uptake in liver, compared to the same construct with a H6-tag. In paper II, it was further shown that an N-terminally placed HEHEHE-tag on ZHER2 provided lower unspecific uptake of radioactivity in liver compared to its H6-tagged counterpart even when radiolabeling was at the C-terminus using alternative chemistries to attach 99mTc, 111In or 125I. In paper III, the H6-tag’s composition and position was varied with regards to charge, hydrophobicity and its C- or N-terminal placement on ZHER2. Among the ten variants investigated, it was found that an N-terminal HEHEHE-tag provided the most favorable overall biodistribution profile and that introduction of hydrophobic and positively charged amino acids provoked liver uptake of radioactivity. In paper IV, the HEHEHE-tag was shown to enable IMAC purification and tri-carbonyl 99mTc-labeling of an IGF-1R-specific Affibody molecule and improved its overall biodistribution when compared to the same construct with a H6-tag. In paper V, the aim was to develop an intracellular receptor-entrapment system to reduce the surface levels of EGFR. An EGFR-specific Affibody molecule was expressed as a fusion to different mutants of an intracellular transport protein in SKOV-3 cells, resulting in a collection of cell lines with 50%, 60%, 80% and 96% reduced surface level of EGFR. Analysis of the proliferation rate of these cell lines showed that a modest reduction (15%) in proliferation occurs between 60% and 80% reduction of the surface level of EGFR.QC 20130129
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Hauke, Christopher Moritz [Verfasser]. "Systematic functionalization of molecules for molecular self-assembly / Christopher Moritz Hauke." Mainz : Universitätsbibliothek Mainz, 2013. http://d-nb.info/1035533227/34.
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Åkesson, Patrik. "Molecular Dynamics of the Adsorption of Organic Molecules on Organic Substrates." Thesis, Linköpings universitet, Institutionen för fysik, kemi och biologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-103688.
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A great interest has been shown for self-assembled organic nano-structures that can be used in a variety of optoelectronic applications, from element detection to home electronics. It is known from experimental research that sexiphenyl (6P) grown on muscovite mica substrate form uniaxially self-assembled nanofibers which together with sexithiophene (6T) deposited on top gives the possibility to tune their polarized emission. A key to continue develop and explore the full potential of this technique is to understand the mechanisms behind the growth. This thesis investigate the initial growth of 6P and 6T on a 6PProject P25154-N20 "Hetero-epitaxy of organic-organic nanofibers"
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Yaneva, Rakina Hristova [Verfasser]. "Molecular mechanism of peptide selection by MHC molecules / Rakina Hristova Yaneva." Bremen : IRC-Library, Information Resource Center der Jacobs University Bremen, 2012. http://d-nb.info/1035265060/34.
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