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Moriarty, John. "Queues, directed percolation and directed polymers." Thesis, University of Oxford, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.433363.
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Lasen, Ulrik Martin. "Dressing wearing : Movement directed by dress - dress directed by movement." Doctoral thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-11052.
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Contemporary dance and modern ballet often focus on conveying emotions through patterns of movement which may be abstract, obvious, or anywhere in between, supported by music, sound, or spoken words that set the mood. Scenography is typically sparse or confined to the available space, leaving the dancers as the main instrument of communication. This work explores dressing and wearing, with a focus on how garments can inform and direct movement, choreography, and performance, and in turn how movement may inform and contribute to the development of dynamic garments. Through a series of live experiments, ranging from self-instigated performance/video work in collaboration with choreographers and dancers to performances of garment interaction associated with everyday life dressing, the performative, spatial, and interactive properties of garments are explored. The results present alternative models of collaborative interaction related to various aspects of kinaesthetics, choreography, scenography, and performance space, and offer wide-ranging creative potential. The work shows how designers and choreographers can collaborate on performance scenarios within the context of modern ballet and contemporary dance productions, thus creating conceptual garments that influence the design, choreography, and movement pattern based on a re-conception of what it means to dress and to wear. In relation to the act of dressing and undressing, alternative types of garment and ways of wearing and performing were found where garments act as co-choreographers in the development of performances. Moreover, by having wearing and dressing as a form of choreography these acts, act as the co-creator of garments both in our everday lives and on stage. As a consequence, the results also demonstrates how the agency of garments can function as a manuscript in modern dance, and how performance itself redefines the notion of wearing and the concept of garments.
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Williams, Aaron. "Packing Directed Joins." Thesis, University of Waterloo, 2004. http://hdl.handle.net/10012/1024.
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Edmonds and Giles conjectured that the maximum number of directed joins in a packing is equal to the minimum weight of a directed cut, for any weighted directed graph. This is a generalization of Woodall's Conjecture (which is still open). Schrijver found the first known counterexample to the Edmonds-Giles Conjecture, while Cornuejols and Guenin found the next two. In this thesis we introduce new counterexamples, and prove that all minimal counterexamples of a certain type have now been found.
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Lee, Vivian Tin-Wai. "User directed prefetching." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ57760.pdf.
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Crawl, Lester Daniel. "Affinity-directed mobility." Diss., Connect to online resource, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3219008.
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Hall, S. A. "Directed homogenous hydrogenation." Thesis, University of Oxford, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355753.
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Singh, Pushpinder 1972-2006. "Failure-directed reformulation." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/46197.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science; and, Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1998.<br>Includes bibliographical references (leaf 58).<br>by Pushpinder Singh.<br>B.S.<br>M.Eng.
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Pacheco, Carlos Ph D. Massachusetts Institute of Technology. "Directed random testing." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/53297.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2009.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (p. 155-162).<br>Random testing can quickly generate many tests, is easy to implement, scales to large software applications, and reveals software errors. But it tends to generate many tests that are illegal or that exercise the same parts of the code as other tests, thus limiting its effectiveness. Directed random testing is a new approach to test generation that overcomes these limitations, by combining a bottom-up generation of tests with runtime guidance. A directed random test generator takes a collection of operations under test and generates new tests incrementally, by randomly selecting operations to apply and finding arguments from among previously-constructed tests. As soon as it generates a new test, the generator executes it, and the result determines whether the test is redundant, illegal, error-revealing, or useful for generating more tests. The technique outputs failing tests pointing to potential errors that should be corrected, and passing tests that can be used for regression testing. The thesis also contributes auxiliary techniques that post-process the generated tests, including a simplification technique that transforms a, failing test into a smaller one that better isolates the cause of failure, and a branch-directed test generation technique that aims to increase the code coverage achieved by the set of generated tests. Applied to 14 widely-used libraries (including the Java JDK and the core .NET framework libraries), directed random testing quickly reveals many serious, previously unknown errors in the libraries. And compared with other test generation tools (model checking, symbolic execution, and traditional random testing), it reveals more errors and achieves higher code coverage.<br>(cont.) In an industrial case study, a test team at Microsoft using the technique discovered in fifteen hours of human effort as many errors as they typically discover in a person-year of effort using other testing methods.<br>by Carlos Pacheco.<br>Ph.D.
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Laos, Roberto. "Protein directed evolution." Revista de Química, 2012. http://repositorio.pucp.edu.pe/index/handle/123456789/99875.
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Evolución dirigida de proteínas: La evolución dirigida es una técnica que nos permite explorar funciones enzimáticas que no son requeridas en el ambiente natural. Esta técnica, simula procesos genéticos naturales y de selección. Esta estrategia se utiliza cuando un diseño racional es muy complicado. Consiste en una repetición de ciclos de diversificación y selección que llevan a la acumulación de mutaciones benéficas. Aquí se presenta dos ejemplos de evolución dirigida con los cuales se ha trabajado directamente: la ADN polimerasa del organismo Thermus aquaticus usada comúnmente en PCR, y la proteína LacI que regula la expresión de genes usados para el metabolismo de lactosa en E. Coli.<br>Directed evolution allows us to explore protein functionalities not required in the natural environment. It mimics natural genetic processes and selective pressures. This approach is used when the molecular basis is not completely understood and rational design is a difficult task. This approach consists of serial cycles of consecutive diversification and selection which eventually lead to the accumulation of beneficial mutations. Here are presented two cases where directed evolution is used to modify two different proteins: Taq polymerase, enzyme used for DNA extension in PCR, and the LacI repressor protein which regulates gene expression on E.coli.
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Lee, Vivian Tin-Wai 1972 Carleton University Dissertation Computer Science. "User directed prefetching." Ottawa.:, 2000.
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Sciboz, Daniel. "Self-directed workgroups." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät II, 2010. http://dx.doi.org/10.18452/16220.
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Die vorliegende Dissertation wurde mit dem Ziel entworfen, ein besseres Verständnis zu erlangen, was die Anforderungen sind, die den künftigen Arbeitsgruppenmitgliedern erlauben, Bedürfnissen von modernen Unternehmen zu genügen. Die Kooperationsbereitschaft von Gruppenmitgliedern scheint ein Schlüsselfaktor zu sein, der ihre Fähigkeit freisetzt, einer beliebigen Aufgabe entgegen zu handeln. Quantitative wie auch qualitative Daten wurden im Rahmen einer explorativen Studie erhoben. Ein Fragebogen (Intercultural Attitude Orientation) wurde mit der Absicht entwickelt, Einstellung von Individuen gegenüber Diversität quer durch Populationen abzufragen. An der explorativen Studie haben 1351 Individuen aus 97 Ländern teilgenommen. Bei einer Faktorenanalyse von 12 Items wurde die entgültige acht Items umfassende Skala gebildet. Eine experimentelle Gruppenstudie wurde entworfen, um Entscheidungsprozesse anzustoßen, die erkennen lassen, ob die Kooperationsbereitschaft der Gruppenmitglieder die Gruppenperformanz erhöht. An der experimetellen Studie haben 249 Individuen teilgenommen, die nach einem Zufallsverfahren in Arbeitsgruppen eingeteilt wurden. Die unabhängigen Variablen waren demografische Gruppenkomposition und Informationsdiversität. Die abhängigen Variablen waren Messungen der Gruppenperformanz. Es wurde festgestellt, dass trotz der demografischen Gruppenkomposition Arbeitsgruppen, die Pakete mit unterschiedlichen Informationen erhielten, besser abgeschnitten haben, als Gruppen, denen Pakete mit ähnlichen Informationen zur Verfügung gestellt wurden. Erfahrung der Gruppenmitglieder mit Diversität, ihre Einstellung gegenüber Diversität, Social Dominance Orientation, Zufriedenheit, Kooperation, Ähnlichkeit in Arbeitsstil und Anzahl der gesprochenen Sprachen wurden getrennt im Hinblick auf die Gruppenergebnisse analysiert. Es wurde herausgefunden, dass diese Messungen in einigen Fällen zueinander in Beziehung standen, was einen Einfluß auf Gruppenprozess hatte.<br>The current dissertation has been designed with the attempt to seek a better understanding of the requirements for prospective workgroup members to fit demands of today''s organizations. Members'' willingness to cooperate appears to be a key factor unlocking their ability to act upon any given task. Quantitative as well as qualitative data have been gathered in the context of an explorative study. A questionnaire (Intercultural Attitude Orientation) has been constructed with the intent to sense individuals'' attitude toward diversity across populations diverging in age, gender, nationality, and occupational status. The explorative study involved the participation of 1351 individuals from 97 different countries. Out of twelve explorative items, one factor solution was extracted, thus building the final 8-item scale. An experimental group study was designed to elicit decision-making procedures set to entangle whether or not members'' readiness to cooperate enhances group performance in the context of a short and cognitively demanding task. The experimental study involved the participation of 249 individuals randomly assigned into workgroups. The two independent variables were group demographical composition and information diversity. Demographical composition was defined either according to national or gender demographics. The outcome variables were measures of workgroup performance. It was found that despite workgroup demographical composition, groups which received diverse information, performed better than workgroups, which received similar information. Members'' quality and quantity of exposure to diversity, attitude toward diversity, social dominance orientation, satisfaction, cooperation, work-style similarity, and number of spoken languages were separately analyzed with regard to group outcomes. Findings revealed that these measures were in some cases linked to one another, thus affecting group process.
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Riahi, Vahid. "Constraint Directed Scheduling." Thesis, Griffith University, 2019. http://hdl.handle.net/10072/386545.
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Scheduling is a decision-making process, which is employed to allocate resources to
tasks in a given time. Scheduling problems are in general NP-hard. In order to solve
scheduling problems, three common types of methods have been used: exact methods
(e.g., branch & bound and dynamic programming), population based metaheuristics
(e.g., genetic algorithm and ant colony optimisation), and local search (LS) algorithms
(e.g., simulated annealing and iterated local search). Exact methods are not able to
address the practical-sized problems effectively with regard to both CPU times and
solution quality. LS algorithms have recently attracted much more attention because of
their simplicity, being easy to implement, robustness, and high effectiveness. However,
the available LS algorithms in the literature typically use a generic structure for speci fic
problems. In other words, the biggest disadvantage of those methods is the lack of
problem speci fic components into their algorithmic structures. To ll in this gap, in this
thesis, we consider constraint-based local search (CBLS) algorithms to solve scheduling
problems because of their effectiveness and also because they are not used much in the
scheduling literature. The key difference of CBLS with other LS algorithms is in the use
of the problem specifi c information in the search process. CBLS helps the search focus
more on areas where efforts will bring more effect, and thus increase the scalability of
the search. In other words, CBLS attempts to exploit the essence of the problem and,
based on the speci ficities of the problem, defi nes the procedures that will guide the
search towards better local optima. The effectiveness of our proposed CBLS techniques is shown throughout this thesis by solving several scheduling problems, such as flowshops with blocking constraints, aircraft operations, and customer order problems.
The first scheduling problem is permutation flowshop scheduling problem (PFSP). It is one of the most thoroughly studied scheduling problems. However, mixed blocking
PFSP (MBPFSP) is a generalised and more realistic version of PFSP with real-life
applications such as cider industry. MBPFSP is an important branch of `zero capacity
buffer' scheduling problems. The second scheduling problem is aircraft scheduling
problem (ASP). ASP involves allocation of aircraft to runways for arrival and departure flights, minimising total delays. In this thesis, we focus on both single-runway and
multiple-runway ASP cases. The third scheduling problem is customer order scheduling
problem (COSP), which has many applications including the pharmaceutical industries
and the paper industries.
All of the three above-mentioned scheduling problems are NP-hard. They have made
signi ficant progress in recent years. However, within practical time limits, existing algorithms
still either find low quality solutions or struggle with practical-sized problems.
In this thesis, we aim to advance their search by better exploiting the problem speci fic
structural knowledge, extracted from the constraints and the objective functions. We
run our experiments on a range of respective standard benchmark problem instances.
Experimental results and comprehensive analyses show that our new algorithms signi ficantly outperform respective state-of-the-art scheduling algorithms.<br>Thesis (PhD Doctorate)<br>Doctor of Philosophy (PhD)<br>Inst Integrated&IntelligentSys<br>Science, Environment, Engineering and Technology<br>Full Text
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Sarajlic, Anida. "Analysing directed network data." Thesis, Imperial College London, 2015. http://hdl.handle.net/10044/1/34381.
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The topology of undirected biological networks, such as protein-protein interaction networks, or genetic interaction networks, has been extensively explored in search of new biological knowledge. Graphlets, small connected non-isomorphic induced sub-graphs of an undirected network, have been particularly useful in computational network biology. Having in mind that a significant portion of biological networks, such as metabolic networks or transcriptional regulatory networks, are directed by nature, we define all up to four node directed graphlets and orbits and implement the directed graphlet and graphlet orbits counting algorithm. We generalise all existing graphlet based measures to the directed case, defining: relative directed graphlet frequency distance, directed graphlet degree distribution similarity, directed graphlet degree vector similarity, and directed graphlet correlation distance. We apply new topological measures to metabolic networks and show that the topology of directed biological networks is correlated with biological function. Finally, we look for topology-function relationships in metabolic networks that are conserved across different species.
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Clarke, Jonathan M. "Directed Schema-based Reasoning." Thesis, Birmingham City University, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.485971.
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This work examines Schema-based Reasoning (SBR) (Turner 1994), a general-purpose problem solver that provides context-centric mediation ofsolutions in open domains~ This thesis will argue that Turner's SBR requires augmentation in commercial and critical applications, in order to obtain a principled adherence to domain-specific, behavioural constraints. An approach is required that balances the preservation ofdomain-specific solution trajectories and context-mediated, opportunistic problem solving found within Turner's SBR. The Directed-SBR model is proposed as the augmentation ofTurner's SBR, with principled extensions that enforce an adherence to such behavioural constraints. The principles augment Turner's SBR by enforcing a further mediation ofthe context-centric p~blem solving, drawing upon a problem domain's viability constraints during solution selection. Furthermore, a problem domain's behavioural constraints are brought into focus as a central consideration during knowledge engineering. This provides focus upon specific domain states, the extraction ofappropriate information from domain ~esources, and at the most appropriate times. The resultant Directed-SBR model establishes a balance between the selection ofthe most appropriate solutions, given the nte~tions ofthe problem solving, while preserving the tasks already unde$ken. be investigation into the adequacies ofTurner's SBRmodel adopts combinatorial pproaches ofquantitative and qualitative research methods. It demonstrates that 'irected-SBR enables the academic and commercial domains examined to be reinforced ith solution mediation that considers domain integrity, in combination with mtext-mediation. Significantly, Directed-SBR has been tested and evaluated in a large ale, distributed, commercial domain, and is operational in a production environment, :ling problem diagnosis, system testing and autonomous support tasks.
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Binz, Marcel. "Learning Goal-Directed Behaviour." Thesis, KTH, Robotik, perception och lärande, RPL, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-213015.
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Learning behaviour of artificial agents is commonly studied in the framework of Reinforcement Learning. Reinforcement Learning gained increasing popularity in the past years. This is partially due to developments that enabled the possibility to employ complex function approximators, such as deep networks, in combination with the framework. Two of the core challenges in Reinforcement Learning are the correct assignment of credits over long periods of time and dealing with sparse rewards. In this thesis we propose a framework based on the notions of goals to tackle these problems. This work implements several components required to obtain a form of goal-directed behaviour, similar to how it is observed in human reasoning. This includes the representation of a goal space, learning how to set goals and finally how to reach them. The framework itself is build upon the options model, which is a common approach for representing temporally extended actions in Reinforcement Learning. All components of the proposed method can be implemented as deep networks and the complete system can be learned in an end-to-end fashion using standard optimization techniques. We evaluate the approachon a set of continuous control problems of increasing difficulty. We show, that we are able to solve a difficult gathering task, which poses a challenge to state-of-the-art Reinforcement Learning algorithms. The presented approach is furthermore able to scale to complex kinematic agents of the MuJoCo benchmark.<br>Inlärning av beteende för artificiella agenter studeras vanligen inom Reinforcement Learning.Reinforcement Learning har på senare tid fått ökad uppmärksamhet, detta berordelvis på utvecklingen som gjort det möjligt att använda komplexa funktionsapproximerare, såsom djupa nätverk, i kombination med Reinforcement Learning. Två av kärnutmaningarnainom reinforcement learning är credit assignment-problemet över långaperioder samt hantering av glesa belöningar. I denna uppsats föreslår vi ett ramverk baseratpå delvisa mål för att hantera dessa problem. Detta arbete undersöker de komponentersom krävs för att få en form av målinriktat beteende, som liknar det som observerasi mänskligt resonemang. Detta inkluderar representation av en målrymd, inlärningav målsättning, och till sist inlärning av beteende för att nå målen. Ramverket byggerpå options-modellen, som är ett gemensamt tillvägagångssätt för att representera temporaltutsträckta åtgärder inom Reinforcement Learning. Alla komponenter i den föreslagnametoden kan implementeras med djupa nätverk och det kompletta systemet kan tränasend-to-end med hjälp av vanliga optimeringstekniker. Vi utvärderar tillvägagångssättetpå en rad kontinuerliga kontrollproblem med varierande svårighetsgrad. Vi visar att vikan lösa en utmanande samlingsuppgift, som tidigare state-of-the-art algoritmer har uppvisatsvårigheter för att hitta lösningar. Den presenterade metoden kan vidare skalas upptill komplexa kinematiska agenter i MuJoCo-simuleringar.
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Marr, Alison M. "Labelings of directed graphs /." Available to subscribers only, 2007. http://proquest.umi.com/pqdweb?did=1362527421&sid=22&Fmt=2&clientId=1509&RQT=309&VName=PQD.
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Ellefson, Bryan A., and University of Lethbridge Faculty of Education. "Teacher-directed professional development." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Education, 1994, 1994. http://hdl.handle.net/10133/54.
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This thesis is an interpretation of the meaning of a professional development project for six high school English teachers in a small, rural jurisdiction. The project design attempts to incorporate guidelines for effective professional development, especially in regard to the way in which authority influences the experience. This study is a case study from a naturalistic inquiry perspective using thnographic techniques. Further, the methodology is educative in the sense that the study was intended to change the situation studied. The analysis attempts to articulate the voices of various authorties in this professional development activity: the voice of leadership, the voice of the collective, the voice of external influences, and the voice of the individual participant. As a professional development activity, this studyindicates that, for the participating teachers, self-directed professional development created conditions conducive to change. Although the voices of professional development authority are incomplete and contradictory, this study provides a view of the landscape of teacher change and growth that is shaped by professional development guidelines concerning function, governance, cultural milieu, leadership, and reflection. These conclusions suggest ways for researchers, administrators, teacher leaders and teachers.to enhance professional development.<br>174 leaves ; 29 cm.
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Bilsland, Alan. "Telomerase directed gene therapy." Thesis, University of Glasgow, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272871.
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Nuttall, Simon. "NOSTRUM : constraint directed diagnosis." Thesis, Open University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.254504.
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Fowle, Chris. "Carbohydrate directed photoaffinity labelling." Thesis, University of Bath, 2018. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.760976.
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Glycoproteins have diverse and essential roles within biological systems. They are formed by enzymatic addition of saccharides to proteins during, or shortly after, translation. However, saccharides can also react with proteins non-enzymatically, a process termed glycation, which can cause impaired function and improper folding. Glycated proteins further react to form advanced glycation end-products, which have been implicated in the pathogenesis and progress of many diseases. Due to this pathological effect, glycation has been studied as a potential biomarker of these diseases. Photoaffinity labelling is a technique that is used to investigate the structure, and presence, of biological molecules; a precedent exists for its use in the study of carbohydrates in biological systems. Chapter 1 outlines the background of this thesis exploring previous studies of glycation, its effects, and methods used in recognition and photoaffinity labelling. Chapter 2 details the design and synthesis of a novel photoaffinity probe, and the optimisation of this synthesis. The target molecule was successfully produced and simpler alternatives to the initial synthetic route with similar yields are discussed. In Chapter 3 the use of the photoaffinity probe is studied. Labelling trials were performed on three proteins: human serum albumin (HSA), macrophage migration inhibitory factor (MIF), and casein. Mass spectrometry showed that the experiments with both HSA and MIF were successful, while the procedure appeared to lead to degradation of casein. Additionally, our work into developing techniques for identifying labelled samples is detailed. A diol-doped electrophoresis gel was not successful created, however, staining protein samples in polyacrylamide gel electrophoresis with curcumin showed promise. Chapter 4 explores the electrochemistry of the photoaffinity probe and details the use of the probe in functionalising a fluorine doped tin oxide (FTO) glass electrode. Cyclic voltammograms of Alizarin Red S (ARS), obtained using a treated electrode, suggest that surface functionalisation was successful.
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Evans, David Elliot 1971. "Policy-directed code safety." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/86424.
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Notowidigdo, Matthew J. (Matthew Joseph) 1981. "User-directed sketch interpretation." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/17961.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2004.<br>Includes bibliographical references (p. 91-92).<br>I present a novel approach to creating structured diagrams (such as flow charts and object diagrams) by combining an off-line sketch recognition system with the user interface of a traditional structured graphics editor. The system, called UDSI (user-directed sketch interpretation), aims to provide drawing freedom by allowing the user to sketch entirely off-line using a pure pen-and-paper interface. The results of the drawing can then be presented to UDSI, which recognizes shapes and lines and text areas that the user can then polish as desired. The system can infer multiple interpretations for a given sketch, to aid during the user's polishing stage. The UDSI program offers three novel features. First, it implements a greedy algorithm for determing alternative interpretations of the user's original pen drawing. Second, it introduces a user interface for selecting from these multiple candidate interpretations. Third, it implements a circle recognizer using a novel circle-detection algorithm and combines it with other hand-coded recognizers to provide a robust sketch recognition system.<br>by Matthew J. Notowidigdo.<br>M.Eng.
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Counts, Jared B. "Knitting with directed graphs." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/119547.
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Thesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2018.<br>This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.<br>Cataloged from student-submitted PDF version of thesis.<br>Includes bibliographical references (pages 67-68).<br>Knitting has historically been communicated by its means of construction. For hand knitting, this is typically a list of instructions or a pictorial grid with knitting symbols. For machine knitting, a similar pictorial grid is used to express needle-level instructions. However, these formats suffer by the nature of their tight coupling with the method used to construct the garments they represent. Alternatively, we use Knit Meshes, which represent knitting structures by their geometry separate from a directed graph description of their topology. This thesis presents an algorithm that can generate a natural, deformed two-dimensional layout of Knit Meshes as well as a conversion pipeline that converts written hand knitting instructions to and from Knit Meshes and an algorithm that converts certain Knit Meshes into knitting machine code.<br>by Jared B. Counts.<br>M. Eng.
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Carton, Sarah Beth, and Sarah Beth Carton. "Intergenerational Child-Directed Artmaking." Thesis, The University of Arizona, 2016. http://hdl.handle.net/10150/621918.
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Throughout this study, I investigate the interaction that occurs between a parent and her child when creating a collaborative drawing. The purpose of this study is to find ways in which to change common images of children and their capabilities in forming and making decisions, problem solving and communication skills, and imaginative story telling abilities. This research seeks to answer some of the following questions: In what ways are children and adults influenced by the child taking ownership of the artmaking experience and how does giving the child ownership and control over the experience change the experience for the adult? I observe two mothers as they collaborate with their young sons (ages 3 and 4) to create a drawing, discuss their experience with them and analyze their final images. Utilizing these methods, I uncover common themes and ideas about the view that adults have of children and ways of shifting these ideas of power and control over to children. I provide my recommendations and implications for the field of early childhood art education and offer a guide for parents when working with their young children.
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Pereira, Marta Daniela Lima Braga Jesus. "Directed evolution of lichenicidin." Master's thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/15282.
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Mestrado em Biologia Molecular e Celular<br>Lichenicidin is a class II lanthipeptide composed by two peptides, Bliα and Bliβ, that is produced by several strains of Bacillus licheniformis. These peptides act synergistically in order to inhibit the growth of other Gram positive bacteria. Due to their antibacterial activity, they are also designated lantibiotics. Unlike other antimicrobial peptides produced by bacteria, lantibiotics are ribosomally synthesized as an immature peptide and suffer several post-translational modifications to achieve their active form. Thus, it is easier the application of bioengineering strategies aiming the creation of new variants with different bioactivity.
The aims of this study were: i) the development a heterologous expression system for the production of lichenicidin allowing a white/blue selection and using E. coli, ii) the generation of two random mutagenesis libraries for each one of the lichenicidin peptides and iii) the selection and analysis of clones with reduced bioactivity when compared with the control.
To develop the heterologous system, preliminary tests were conducted that allowed the selection of E. coli Mach1 as the recipient strain. In addition, 37 ºC was established as the best temperature for lichenicidin production. Thus, two random mutagenesis libraries of the structural genes licA1 and licA2, encoding the precursor peptides of Bliα and Bliβ, respectively. Subsequently, the bioactivity of around 4000 clones of each library was analyzed by colony-agar bioassay. In the present study, colonies with improved activity were not possible to detect in any of the libraries. Regarding the Bliα library, about 4,5 % of the clones showed null bioactivity, while 2,6 % and 2,2 % of the clones showed very reduced and activity reduced to half when compared with the control, respectively. In the Bliβ library, the values were very similar since about 5,1 % of the clones showed no bioactivity, 1,4 % showed very reduced activity and 3,8 % had activity reduced to half when compared with the control. Some of these clones were selected for sequencing reaction in order to identify the mutations causing the observed phenotypes. This analysis confirmed the importance of the conserved residues for the bioactivity of both peptides. Moreover, it was found that substitutions involving charged amino acids and prolines result in the production of inactive peptides.<br>A lichenicidina é um lantipéptido da classe II constituído por dois péptidos, Bliα e Bliβ, produzido por diversas estirpes de Bacillus licheniformis. Estes péptidos atuam sinergisticamente, de forma a inibirem o crescimento de outras bactérias de Gram positivo, sendo por isso também designados de lantibióticos. Ao contrário de outros compostos antimicrobianos produzidos por bactérias, os lantibióticos são produzidos na sua forma imatura diretamente pelo ribossoma e sofrem diversas alterações pós-traducionais, que os tornam péptidos ativos. Desta forma, torna-se mais fácil a aplicação de técnicas de bioengenharia de modo a obter novas variantes com bioatividade alterada.
Os objetivos deste trabalho foram i) a construção de um sistema de expressão heteróloga da lichenicidina em E. coli que permitisse a seleção azul/branco, ii) a construção de uma biblioteca por mutagénese aleatória para cada um dos péptidos que constituem a lichenicidina e iii) a seleção e análise de clones com bioatividade reduzida relativamente ao controlo.
Para a criação do sistema de expressão heteróloga, foram realizados vários ensaios preliminares, que levaram à seleção da estirpe E. coli Mach1 como recetora assim como à seleção da temperatura de produção de 37 ºC. Assim sendo, foram construídas duas bibliotecas por mutagénese aleatória dos genes estruturais licA1 e licA2, que codificam os péptidos percursores de Bliα e Bliβ, respetivamente. Subsequentemente, a bioatividade de cerca de 4000 clones de cada biblioteca foi analisada através de bioensaio em agar. Através desta análise, não foi possível detetar nenhum clone com bioatividade aumentada em ambas as bibliotecas. Relativamente à biblioteca do péptido Bliα, cerca de 4,5 % dos clones apresentaram bioatividade nula, enquanto que 2,6 % e 2,2 % dos clones apresentaram atividade muito reduzida e atividade reduzida a metade quando comparada com o controlo, respetivamente. Na biblioteca do péptido Bliβ, os valores foram bastante semelhantes, com cerca de 5,1 % dos clones a exibir atividade nula, 1,4 % com atividade muito reduzida e 3,8 % com atividade reduzida a metade quando comparada com o controlo. A sequência dos genes estruturais de alguns destes clones foram analisados, com o objetivo de identificar as alterações responsáveis por estes fenótipos. Esta análise confirmou a importância dos resíduos conservados para a bioatividade dos dois péptidos. Foi também possível reconhecer que substituições envolvendo aminoácidos carregados e prolinas resultam na produção de péptidos inativos.
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Sato, Toshinori. "History Directed Processor Architecture." Kyoto University, 1999. http://hdl.handle.net/2433/182380.
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Shallcross, Wendy L. "Enhanced attention to "motionese" do infants prefer infant-directed to adult-directed action? /." Click here for download, 2006. http://wwwlib.umi.com/cr/villanova/fullcit?p1434312.
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Gill, Michael Joseph. "Rethinking social stereotypes : moving from individual-directed to group-directed thought and behavior /." Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.
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Weber, Denise L. "Self-directed engineering learning laboratories." Laramie, Wyo. : University of Wyoming, 2009. http://proquest.umi.com/pqdweb?did=1939351921&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.
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Oakes, Mark A. "Directed forgetting of autobiographical events /." Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/9118.
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Timmons, Michael. "Directed Ortho-Metalation of Dimethylarylamines." TopSCHOLAR®, 2002. http://digitalcommons.wku.edu/theses/641.
Full textAbstract:
Site-specific product(s) from the reaction of benzene derivatives with various reagents is a need of researchers at numerous laboratories, particularly those in the pharmaceutical industry. Such derivatives can be synthesized directly, i.e., by substitution of a proton, using either of two procedures: electrophilic aromatic substitution (EAS) or directed ortho-metalation (DoM). Directed ortho-metalation (DoM) is an alternative aromatic substitution process initiated by organolithium reagents which provides regiospecific substitution exclusively at the ortho- position (equation). The focus of this study is to find hydrocarbon media that will permit the maximum extent of metalation of several dimethylarylamines. The dimethylamine-containing substituents constitute directing metalation groups (DMG's) for the various aryl systems investigated. Maximization of the extents of ortho-lithiation of dimethylaniline [DMG = - N(CH3)2] and dimethylbenzylamine [DMG = -CH2N(CH3)2] have now been achieved using novel combinations of solvent, temperature and increments of catalyst. Studies of substituted dimethylanilines and dimethylbenzylamines containing a second DMG have yielded mixed results. Both metalation condition parameters as well as certain mechanistic aspects are altered by inclusion of a second DMG into these two parent systems.
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Snowdon, David Computer Science & Engineering Faculty of Engineering UNSW. "Operating system directed power management." Awarded By:University of New South Wales. Computer Science & Engineering, 2010. http://handle.unsw.edu.au/1959.4/44747.
Full textAbstract:
Energy is a critical resource in all types of computing systems from servers, where energy costs dominate data centre expenses and carbon footprints, to embedded systems, where the system's battery life limits the device's functionality. In their efforts to reduce the energy use of these system's hardware manufacturers have implemented features which allow a reduced energy consumption under software control. This thesis shows that managing these settings is a more complex problem than previously considered. Where much (but not all) of the previous academic research investigates unrealistic scenarios, this thesis presents a solution to managing the power on varying hardware. Instead of making unrealistic assumptions, we extract a model from empirical data and characterise that model. Our models estimate the effect of different power management settings on the behaviour of the hardware platform, taking into account the workload, platform and environmental characteristics, but without any kind of a-priori knowledge of the specific workloads being run. These models encapsulate a system's knowledge of the platform. We also developed a \emph{generalised energy-delay} policy which allows us to quickly express the instantaneous importance of both performance and energy to the system. It allows us to select a power management strategy from a number of options. This thesis shows, by evaluation on a number of platforms, that our implementation, Koala, can accurately meet energy and performance goals. In some cases, our system saves 26\% of the system-level energy required for a task, while losing only 1\% performance. This is nearly 46\% of the dynamic energy. Taking advantage of all energy-saving opportunities requires detailed platform, workload and environmental information. Given this knowledge, we reach the exciting conclusion that near optimal power management is possible on real operating systems, with real platforms and real workloads.
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Huang, Ce. "Directed search for differentiated goods." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/40415.
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In three directed search models with horizontal differentiation, this thesis characterizes the unique symmetric equilibrium for each model and studies the welfare property of equilibrium allocations. In Chapter 2, horizontal differentiation is modeled as buyers' valuations being independent. In equilibrium, sellers use a mixed strategy with the support consisting of a countable number of prices. Equilibrium price dispersion exists and equilibrium allocation is constrained inefficient due to price dispersion. Chapter 3 extends the model in Chapter 2 by allowing different degrees of horizontal differentiation. With large degrees of horizontal differentiation, sellers use a mixed strategy qualitatively similar to the equilibrium in Chapter 2. With small degrees of differentiation, sellers use a pure strategy. Chapter 4 extends the model in Chapter 2 by allowing differentiation to be endogenous. Initially buyers are equally uncertain about the characteristics of sellers' goods and no differentiation exists. Then sellers choose prices together with the amounts of information disclosed to buyers about the characteristics of sellers' goods. Information disclosure leads to differentiation after buyers receive the information. It is shown that a seller's profit by disclosing full information is higher than that by disclosing partial information. In equilibrium both sellers disclose full information and use a pricing strategy that is identical to the equilibrium in Chapter 2.
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Mahoney, Richard M. "Human target-directed position control." Thesis, University of Cambridge, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320154.
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Hegazy, Amany Saber. "Directed lithiation of substituted benzylamines." Thesis, Cardiff University, 2009. http://orca.cf.ac.uk/54873/.
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CHAPTER SIX Chapter six describes a lithiation procedure that allows the production of 3-substituted isoindolin-l-ones in high yields in only one step via lithiation of various substituted N-benzyl-MN-dimethylureas with /-BuLi (3.3 mole equivalents) in THF at 0 °C followed by reactions with various electrophiles. The procedure has been proven to be simple, efficient and general.
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Boore, Graeme C. "Directed graph iterated function systems." Thesis, University of St Andrews, 2011. http://hdl.handle.net/10023/2109.
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This thesis concerns an active research area within fractal geometry. In the first part, in Chapters 2 and 3, for directed graph iterated function systems (IFSs) defined on ℝ, we prove that a class of 2-vertex directed graph IFSs have attractors that cannot be the attractors of standard (1-vertex directed graph) IFSs, with or without separation conditions. We also calculate their exact Hausdorff measure. Thus we are able to identify a new class of attractors for which the exact Hausdorff measure is known. We give a constructive algorithm for calculating the set of gap lengths of any attractor as a finite union of cosets of finitely generated semigroups of positive real numbers. The generators of these semigroups are contracting similarity ratios of simple cycles in the directed graph. The algorithm works for any IFS defined on ℝ with no limit on the number of vertices in the directed graph, provided a separation condition holds. The second part, in Chapter 4, applies to directed graph IFSs defined on ℝⁿ . We obtain an explicit calculable value for the power law behaviour as r → 0⁺ , of the qth packing moment of μ[subscript(u)], the self-similar measure at a vertex u, for the non-lattice case, with a corresponding limit for the lattice case. We do this (i) for any q ∈ ℝ if the strong separation condition holds, (ii) for q ≥ 0 if the weaker open set condition holds and a specified non-negative matrix associated with the system is irreducible. In the non-lattice case this enables the rate of convergence of the packing L[superscript(q)]-spectrum of μ[subscript(u)] to be determined. We also show, for (ii) but allowing q ∈ ℝ, that the upper multifractal q box-dimension with respect to μ[subscript(u)], of the set consisting of all the intersections of the components of F[subscript(u)], is strictly less than the multifractal q Hausdorff dimension with respect to μ[subscript(u)] of F[subscript(u)].
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Ioannou, Avgousta. "Directed Evolution of Galactose Oxidase." Thesis, University of Manchester, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.508541.
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Simha, Ramanuja N. "Mining Associations Using Directed Hypergraphs." Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3345.
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This thesis proposes a novel directed hypergraph based model for any database. We introduce the notion of association rules for multi-valued attributes, which is an adaptation of the definition of quantitative association rules known in the literature. The association rules for multi-valued attributes are integrated in building the directed hypergraph model. This model allows to capture attribute-level associations and their strength. Basing on this model, we provide association-based similarity notions between any two attributes and present a method for finding clusters of similar attributes. We then propose algorithms to identify a subset of attributes known as a leading indicator that influences the values of almost all other attributes. Finally, we present an association-based classifier that can be used to predict values of attributes. We demonstrate the effectiveness of our proposed model, notions, algorithms, and classifier through experiments on a financial time-series data set (S&P 500).
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Bebbington, Magnus W. P. "Nitrogen-directed free radical rearrangements." Thesis, University of Oxford, 2002. http://ora.ox.ac.uk/objects/uuid:316d2379-4019-4361-937d-ff1e064f8bb9.
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This thesis describes efforts to develop new methods for the synthesis of bridged azacycles using nitrogen-directed free radical rearrangements. Free radical addition to 7-azanorbornadienes were carried out to give 7-substituted 2- azanorbornenes (Scheme a.l, X-Y = RS-H or PhSe-H). [illustration in text ...] Scheme a. 1 Nitrogen-directed homoallylic radical rearrangement via intermolecular radical addition. A conceptually novel and theoretically interesting nitrogen-directed neophyl rearrangement (Scheme a.2) was developed into a synthesis of 2- azabenzonorbornanes 2. [illustration in text ...] Scheme a.2 Nitrogen-directed neophyl-like rearrangement to 2-azabenzonorbornanes. In this case the radical 1 was generated by Barton deoxygenation of 7- azabenzonorbornanols. The effect on rearrangement of bicyclic core substitution and of aromatic ring electronics was probed in some detail, and the process was synthetically useful for a wide range of substrates. Variation of the protecting group on nitrogen was investigated and the product profiles from neophyl-like rearrangement were consistent with a process driven by the stability of a radical α to nitrogen as a result of SOMO-lone pair orbital interaction. The kinetics and mechanism of these processes are examined where appropriate, leading to estimates of rate constants for the rearrangements.
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Frazer, D. V. "Synthetic studies directed at upial." Thesis, University of Glasgow, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.374511.
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Greenwell, David Robert. "Template directed synthesis of oligosaccharides." Thesis, University of Leeds, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275698.
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Ennis, David. "Directed metallation in heteroaromatic synthesis." Thesis, University of Liverpool, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293734.
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Kelly, Luke Tristian. "On cycles in directed graphs." Thesis, University of Birmingham, 2010. http://etheses.bham.ac.uk//id/eprint/940/.
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The main results of this thesis are the following. We show that for each alpha > 0 every sufficiently large oriented graph G with minimum indegree and minimum outdegree at least 3 |G| / 8 + alpha |G| contains a Hamilton cycle. This gives an approximate solution to a problem of Thomassen. Furthermore, answering completely a conjecture of Haggkvist and Thomason, we show that we get every possible orientation of a Hamilton cycle. We also deal extensively with short cycles, showing that for each l > 4 every sufficiently large oriented graph G with minimum indegree and minimum outdegree at least |G| / 3 + 1 contains an l-cycle. This is best possible for all those l > 3 which are not divisible by 3. Surprisingly, for some other values of l, an l-cycle is forced by a much weaker minimum degree condition. We propose and discuss a conjecture regarding the precise minimum degree which forces an l-cycle (with l > 3 divisible by 3) in an oriented graph. We also give an application of our results to pancyclicity.
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Brown, Jeremy Hanford 1972. "Feedback-directed specialization of C." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/36604.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1995.<br>Includes bibliographical references (p. 115-116).<br>by Jeremy H. Brown.<br>M.Eng.
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Faul, C. F. J. (Charles Frederick James). "Directed synthesis of polymer mesostructures." Thesis, Stellenbosch : Stellenbosch University, 2000. http://hdl.handle.net/10019.1/51729.
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Thesis (PhD)--Stellenbosch University, 2000.<br>ENGLISH ABSTRACT: The objective of this research was to produce discrete, nano-shaped polymeric structures on the
same length scale as, or one to one copies of, templates, deformable templates or structure-directing
hosts.
Polymerisation of hydrophobic organic monomers in high concentration surfactant solutions, leads
to the formation of shaped particles (rod-like, plank-like and ribbon-like particles) in the
micrometer size range. The origin of these regularly shaped particles was investigated. It is
proposed that they were not polymeric in nature, but formed by the crystallisation of the surfactant
in the presence of electrolytes and ethanol as solvent. The polymeric particles that were formed
were found to be of spherical shape, and no directing of the shape was detected.
Mesostructured hosts were then investigated for their possible use as structure-directing agents. A
series of polyelectrolyte-surfactant complexes of polydiallylammonium chloride with sodium
sulphate surfactants (ranging from C10 to C16) were synthesised and characterised in terms of their
thermal, mechanical and structural properties. The complex of polydiallylammonium chloride and
sodium dodecyl sulphate was selected as an appropriate self-assembled model system for
investigations into the structure-directing properties of these new materials.
The polymerisation of hydrophobic organic monomers, such as styrene and the di-functional
monomer m-diisopropenylbenzene (m-DIB), within the above mesoscopically structured
polyelectrolyte-surfactant complex as host, lead to the formation of unconventionally shaped
polymeric particles. The influence of the presence of monomers and guest polymers on the phase
morphology of the host was investigated by small angle X-ray analyses (SAXS) and dynamic
mechanical analyses (DMA). SAXS analyses showed that these new, stable hosts can hold up to 17
% guest polymer before phase disruption is encountered. These findings were supported by
changes in the mechanical properties, as determined by DMA. The transmission electron
microscopy (TEM) images of particles obtained after polymerisation showed very clearly that the
poly-(m-DIB) did not form a continuous copy of the 3D hexagonal structure of the host, but rather
colloidal copies of a part of the host structure that swelled the most. The shapes of the polymer
mesostructures were dictated by the morphology of the phase of the structure-directing host, to produce nanosized wires (dimensions 4 by 100 nm), cigar-shaped particles (dimensions 8 by 50 nm)
and fibrillar bent shapes (larger than 200 nm), as revealed by TEM.
According to literature these are the first shaped, polymer nano-particles produced in a soft, selfassembled,
organic templating host.<br>AFRIKAANSE OPSOMMING: Die doel van hierdie navorsing was om diskrete, nano-gevormde polimeriese partikels van dieselfde
lengteskaal as, of direkte een tot een kopië van, 'n templaat, 'n vervormbare of struktuur-rigtende
gasheersisteem te produseer.
Die polimerisasie van hidrofobiese organiese monomere in seep oplossings van hoë konsentrasie,
het gelei tot die produksie van gevormde partikels. Die oorsprong van hierdie partikels is
ondersoek. Dit word voorgestel dat die partikels nie polimeries van aard is nie, maar gevorm is
deur die kristallisasie van die seep in die teenwoordigheid van elekotroliete en etanol as
oplosmiddel. Die polimeriese partikels wat wel geproduseer is, was sferies in vorm, en geen
rigtende invloed op die vorm van die partikels is waargeneem nie.
Meso-gestruktureerde gasheersisteme is ook ondersoek vir moontlike gebruik as struktuur-rigtende
agente. 'n Reeks poliëlektroliet-seep komplekse van polidiallielammoniumchloried en
natriumsulfaat sepe (van C10 tot C16) is gesintetiseer en gekarakteriseer in terme van hul termiese,
meganiese en strukturele eienskappe. Die kompleks van polidiallielammoniumchloried en natrium
dodekielsulfaat is gekies as 'n toepaslike self-organiserende modelsisteem vir die ondersoeke na die
struktuur-rigtende eienskappe van hierdie nuwe materiale.
Polimerisasie van hidrofobiese organiese monomere, soos byvoorbeeld stireen en die di-funksionele
monomeer m-di-isopropenielbenseen (m-DIB), in hierdie mesoskopies-gestruktureerde
poliëlektroliet-seep kompleks, het gelei tot die vorming van nie-konvensionele gevormde
polimeriese partikels. Die invloed van die teenwoordigheid van monomere en gaspolimere op die
fasemorfologie van die gasheersisteem is ondersoek d.m.v. kleinhoek X-straal diffraksie (Eng.
SAXS) en dinamiese meganiese analise (DMA). SAXS analises het aangetoon dat hierdie nuwe,
stabiele gasheersisteem tot 17 % gaspolimeer kan inkorporeer voordat fasevernietiging plaasvind.
Hierdie resultate is verder ondersteun deur veranderinge in die meganiese eienskappe soos
waargeneem deur DMA. Transmissie elektronmikroskopie (TEM) afbeeldinge van partikels
geïsoleer na polimerisasie het baie duidelik gewys dat, in die geval van poli-(m-DIB), die
gaspolimeer nie 'n kontinue kopie van die drie dimensionele heksagonale struktuur van die
gasheersisteem produseer nie. Daar word eerder 'kolloïdale kopieë' van dele van die
gasheersisteem wat die meeste swel gevorm. Die vorms van die polimeer mesostrukture word dus
bepaal deur die morfologie van die fase van die struktuur-rigtende gasheer, om nanogrootte draadjies (dimensies 4 x 100 nm), sigaarvormige partikels (8 x 50 nm) en fibrillêre gebuigde vorms
(groter as 200 nm) te vorm, soos waargeneem met TEM.
Volgens die literatuur is hierdie die eerste geval van gevormde polimeer nanopartikels geproduseer
in 'n self-organiserende templaat gasheersisteem.
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Bhat, Venugopal T. "Protein-directed dynamic combinatorial chemistry." Thesis, University of Edinburgh, 2011. http://hdl.handle.net/1842/8758.
Full textAbstract:
Dynamic combinatorial chemistry (DCC) is a novel approach to medicinal chemistry which integrates the synthesis and screening of small molecule libraries into a single step. The concept uses reversible chemical reactions to present a dynamic library of candidate structures to a template which selects and removes the best binder from equilibrium. Using this evolutionary process with a biopolymer template, such as a protein, leads to the protein directing the synthesis of its own best ligand. Biological DCC applications are extremely challenging since the thermodynamic criterion of reversibility has to be met under physiological conditions to ensure stability of the biomolecular template. The list of reversible reactions satisfying these stringent criteria is limited and is a major constraint on achieving both reaction and structural diversity in adaptive dynamic libraries. This thesis reports the development of a catalysed version of acylhydrazone dynamic libraries which are truly adaptive under protein-friendly conditions. In the presence of aniline as a trans-imination catalyst, acylhydrazone dynamic combinatorial libraries equilibrate rapidly at pH 6.2 and are switched off by an increase in pH. We designed acylhydrazone libraries targeting the enzyme superfamily Glutathione-S-Transferase (GST) using a scaffold aldehyde, 4-chloro-3-nitrobenzaldehyde, which is structurally related to a known GST substrate chlorodinitrobenzene. On interfacing these dynamic libraries with two different GST enzymes (SjGST from the helminth worm Schistosoma japonicum and hGSTP1-1, a human isoform and an important oncology drug target) we observed isoformselective amplification effects with two different acylhydrazones selected by the proteins. To explore the potential of anchoring in our DCC methodology we conjugated the endogenous GST ligand, glutathione (GSH) onto the scaffold chloronitrobenzaldehyde. The GSH recognition motif acts as an anchor and allows us to explore the hydrophobic binding site of the enzyme in a fragment-based approach. The presence of the glutathione moiety led to increased solubility of the library members and a DCC experiment with the enzymes led to the selection of conjugate hydrazones with significant binding ability. Multi-level dynamic libraries use multiple exchange processes in the same system to increase their accessible structural diversity. These exchange reactions may be orthogonal, where the different chemistries can be activated or deactivated independently of each other, or simultaneous, where all the processes are dynamic and crossover under the same conditions. Together, these interacting molecular networks provide an exciting experimental approach to the emerging field of systems chemistry. We demonstrate that two reversible reactions, conjugate addition of thiols to enones and hydrazone formation, are fully compatible and orthogonal to one another in a single dynamic library. Hydrazone exchange takes place at acidic pH, while conjugate addition operates at basic pH. Simple pH change can be used to switch between each process and establish two channels of reactivity.
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Giustiniano, Francesco. "Directed assembly of functional patterns." Thesis, University of Southampton, 2010. https://eprints.soton.ac.uk/191341/.
Full textAbstract:
In this work, density functional theory (DFT) was used to obtain microscopic structures of heterogeneous catalysts based on rhodium supported on a metal oxide (-Al2O3). Two different methodologies were used. The first methodology uses a periodic model and a plane-wave basis set to solve the Schrödinger equation in the framework of Bloch’s theorem. The optimised structures of RhI(CO)2/ -Al2O3 species obtained at this level of theory have bond lengths in agreement with experimental EXAFS determinations. The weighted linear combination of Rh K-edge XANES spectra computed using the three most dominant structures reproduces well the phase and shape of the oscillations of the experimental XANES spectrum, providing support for the computed structures. The second methodology is based on hybrid quantum mechanical (QM)/molecular mechanical (MM) calculations. Within this scheme the support is described at the MM level of theory while the region of interest, the absorption site where the surface RhI(CO)2 complex lies, is described with a suitable QM approach. These hybrid calculations performed at the PBE/ECP/cc-pVDZ level of theory were used to obtainminimum-energy structures and harmonic stretching frequencies of RhI(CO)2/-Al2O3 species. The computed bond lengths and harmonic stretching frequencies were in good agreement with the experimental evidence and with the results obtained using periodic models.
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Cole, Julian. "Graph directed self-conformal multifractals." Thesis, University of St Andrews, 1999. http://hdl.handle.net/10023/13903.
Full textAbstract:
In this thesis we study the multifractal structure of graph directed self-conformal measures. We begin by introducing a number of notions from geometric measure theory. In particular, several notions of dimension, graph directed iterated function schemes, and the thermodynamic formalism. We then give an historical introduction to multifractal analysis. Finally, we develop our own contribution to multifractal analysis. Our own contribution to multifractal analysis can be broken into three parts; the proof of two multifractal density theorems, the calculation of the multifractal spectrum of self-conformal measures coded by graph directed iterated function schemes, and the introduction of a relative multifractal formalism together with an investigation of the relative multifractal structure of one graph directed self-conformal measure with respect to another. Specifically, in Chapter 5 we show that by interpreting the multifractal Hausdorff and packing measures Olsen introduced in [0195] as Henstock-Thomson variation measures we are able to obtain two stronger density theorems than those obtained by Olsen. In Chapter 6 we give full details of the calculation of the multifractal spectrum of graph directed self-conformal measures satisfying the strong open set condition and show that the multifractal Hausdorff and packing measures introduced by Olsen in [0195] take positive and finite values at the critical dimension provided that the self-conformal measures satisfy the strong separation condition. In Chapter 7 we formalise the idea of performing multifractal analysis with respect to an arbitrary reference measure by developing a formalism for the multifractal analysis of one measure with respect to another. This formalism is based on the ideas of the 'multifractal formalism' as first introduced by Halsey et. al. [HJKPS86] and closely parallels Olsen's formal treatment of this formalism in [0195]. In Chapter 8 we illustrate our relative multifractal formalism by investigating the relative multifractal structure of one graph directed self-conformal measure with respect to another where the two measures are based on the same graph directed self-conformal iterated function scheme which satisfies the strong open set condition.
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Tapia, Nikolas. "Directed polymers and rough paths." Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUS363.
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Les Équations aux Dérivées Partielles Stochastiques (SPDE en anglais) sont un outil essentiel pour l'analyse des limites d'échelle de divers modèles microscopiques provenant d'autres aires des sciences telles que la physique ou la chimie. Ce type d'équations corresponds à une équations aux dérivées partielles classique à laquelle on a ajouté un terme de force externe aléatoire qui est très irrégulier ; l'exemple le plus basique est peut-être l'Équation de la Chaleur Stochastique, qui est étudiée dans une de ses version dans cette thèse. L'irrégularité du potentiel fait que l'analyse des solutions à ce problème soit beaucoup plus compliqué que dans le cas classique. En fait, il y a des cas où les solutions ne peuvent être définies que dans le sens des distributions (ou des fonctions généralisées). Il y a des cas critiques comme l'équations de Kardar-Parisi-Zhang (KPZ) dans une dimension d'espace où, bien que ces solutions sont Hölderiennes, elles ne sont pas assez régulières pour définir quelques termes non linéaires qu'y apparaissent. Durant les 20 dernières années des techniques pour l'analyse de ces équations ont été développées parmi lesquelles il y a les chemins rugueux géométriques de T. Lyons (1998), les chemins rugueux ramifiés de M. Gubinelli (2010) et plus récemment les structures de régularité de M. Hairer (2014), pour laquelle ce dernier à remporté la médaille Fields en 2014. Toutes ces techniques ont comme idée centrale le concept de renormalisation (provenant de la physique). En particulier, la renormalisation de Wick joue un rôle essentiel dans la théorie des structures de régularité. Dans ce travail nous développons les produits et polynômes de Wick d'un point de vue algébrique inspiré du "calcul ombrale" de G.-C. Rota. Nous explorons aussi la théorie générale des chemins rugueux et leur version ramifié en particulier, où nous donnons des résultats nouveaux dans la direction d'incorporer un analogue de la renormalisation de Wick existant dans la théorie de Hairer. Finalement, le modèle de polymère semidiscret multicouches, introduit par I. Corwin et A. Hammond (2014) est étudié. Nous montrons la convergence de sa fonction de partition vers le processus stochastique appelé "la solution de l'équation de la chaleur stochastique multicouches" par N. O'Connell et J. Warren (2011) quelques années avant. Nous remarquons qu'au moment de rédaction de cette thèse il n'existait aucun résultat permettant interpréter ce dernier processus dans le continuum comme la solution d'une SPDE singulière comme dans le cas, par exemple, de l'équation de KPZ. Ceci a été une des principales sources d'inspiration pour ce travail<br>Stochastic Partial Differential Equations are an essential tool for the analysis of scaling limits of a diverse array of microscopic models coming from other fields such as physics and chemistry.This type of equations correspond to classical partial differential equations to which one has added a random forcing which is typically very irregular ; the most basic example is perhaps the Stochastic Heat Equation, one of whose versions is studied in this thesis. The roughness of the potential turns the analysis of solutions to these probles a lot more difficult than the classic case. In fact, there are cases where solutions can be understood only in the sense of distributions, i.e. as generalised functions. There are some critical cases, such the Kardar-Parisi-Zhang (KPZ)equation where, even though the solutions can be shown to be continuous (even Hölder continuous) they are not regular enough so that some non-linear terms appearing in this equation are well defined. In the last 20 years certain techniques have been developed for the analysis of these equations, among which there is the theory of Rough Paths by T. Lyons (1998), their branched version introduced by M. Gubinelli (2010) and more recently the theory of Regularity Structures of M. Hairer (2014) and for which he was awarded the Fields Medal in 2014. All these techniques have as main idea that of renormalisation, coming from physics. In particular, Wick renormalisation plays an essential role in Regularity Structures. In this work we develop Wick products and polynomials from a Hopf-algebraic point of view, inspired by G.-C. Rota's Umbral Calculus. We also explore the general theory of Rough Paths and in particular in their branched version, where we show some new results in the direction of incorporating an analogue of Wick renormalisation as found in Hairer's Regularity Structures. Finally, the semi-discrete multi-layer polymer model, introduced by I. Corwin and A. Hammond (2014) is studied. We show the convergence of its partition function towards a stochastic process known as (the solution to) "the multi-layer Stochastic Heat Equation" introduced by N. O'Connell and J. Warren (2011) some years earlier. We remark that at the time of writing of this work there were no results allowing to interpret this last process as the solution to a singular SPDE as is the case, for example, for the KPZ equation. This was one of the main sources of inspiration of this work
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