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Oldelius, David, and Douglas Pham. "Master Data Management-studie om nästa entiteto och leverantör för Scania." Thesis, KTH, Hälsoinformatik och logistik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-230108.
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Stora företag har olika avdelningar där informationen från dessa måste hanteras. Master Data Management(MDM) är ett informationshanteringssystem för att hantera information från olika källor. En MDM-implementation sker med en entitet i taget. Arbetets problemställning är att rekommendera nästa entitet att inkludera i MDM-implementationen hos Scania samt vilken leverantör som passar till implementationen. En rekommendation av entitet framställs av material från Scania och intervjuer med anställda på Scania. Rekommendationen av leverantör framställs från material från leverantörer och intervjuer med leverantörerna. Entiteten som rekommenderas är produkt som individ för att informationen i området har behov av förbättrad hantering och entiteten är nära kärnverksamheten. Orchestra Networks är leverantören som rekommenderas för att de ligger i framkant inom MDM, de är nischade mot området och är starka inom produktinformation.Enterprises has different departments and the information from them needs management. Master Data Management(MDM) is an information handling system for handling information from different sources. One entity at the time is implemented to MDM. The work's problem is to recommend the next entity to include in the MDM implementation at Scania as well as which provider fits the implementation. A recommendation of entity is prepared from materials provided by Scania and interviews with employees at Scania. A recommendation of provider is prepared from materials from the providers and interviews with the providers. The recommended entity is product as individual because information in the area needs improved management. Orchestra Networks is the recommended supplier because they are a leader among the MDM providers, they are specialised in the area and they are strong in the product information area.
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Stolzer, Maureen. "Phylogenetic Inference for Multidomain Proteins." Research Showcase @ CMU, 2011. http://repository.cmu.edu/dissertations/47.
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In this thesis, I present a model of multidomain evolution with associated algorithms and software for phylogenetic analysis of multidomain families, as well as applications of this novel methodology to case-studies and the human genome.
Phylogenetic analysis is of central importance to understanding the origins and evolution of life on earth. In biomedical research, molecular phylogenetics has proved an essential tool for practical applications. Current molecular phylogenetic methods are not equipped, however, to model many of the unique characteristics of multidomain families. Genes that encode this large and important class of proteins are characterized by a mosaic of sequence fragments that encode structural or functional modules, called domains. Multidomain families evolve via domain shuffling, a process that includes insertion, internal duplication, and deletion of domains. This versatile evolutionary mechanism played a transformative role in major evolutionary transitions, including the emergence of multicellular animals and the vertebrate immune system.
Multidomain families are ill-suited to current methods for phylogeny reconstruction due to their mosaic composition. Different regions of the same protein may have different evolutionary histories. Moreover, a protein may contain domains that also occur in otherwise unrelated proteins. These attributes pose substantial obstacles for phylogenetic methods that require a multiple sequence alignment as input. In addition, current methods do not incorporate a model of domain shuffling and hence, cannot infer the events that occurred in the history of the family. I address this problem by treating a multidomain family as a set of co-evolving domains, each with its own history. If the family is evolving by vertical descent from a conserved set of ancestral domains, then all constituent domains will have the same phylogenetic history. Disagreement between domain tree topologies is evidence that the family evolved through processes other than speciation and gene duplication. My algorithms exploit this information to reconstruct the history of domain shuffling in the family, as well as the timing of these events and the ancestral domain composition. I have implemented these algorithms in software that outputs the most parsimonious history of events for each domain family. The software also reconstructs a composite family history, including duplications, insertions and losses of all constituent domains and ancestral domain composition.
My approach is capable of more detailed and accurate reconstructions than the widely used domain architecture model, which ignores sequence variation between domain instances. In contrast, my approach is based on an explicit model of events and captures sequence variation between domain instances. I demonstrate the utility of this method through case studies of notch-related proteins, protein tyrosine kinases, and membrane-associated guanylate kinases. I further present a largescale analysis of domain shuffling processes through comparison of all pairs of domain families that co-occur in a protein in the human genome. These analyses suggest that (1) a remarkably greater amount of domain shuffling may have occurred than previously thought and (2) that it is not uncommon for the same domain architecture to arise more than once through independent events. This stands in contrast to earlier reports that convergent evolution of domain architecture is rare and suggests that incorporating sequence variation in evolutionary analyses of multidomain families is a crucial requirement for accurate inference.
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Scott, Kathryn Anne. "Biophysical studies of multidomain proteins." Thesis, University of Cambridge, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.616134.
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Apic, Gordana. "Evolution of multidomain proteins in genomes." Thesis, University of Cambridge, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.619919.
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Stanescu, Dan. "A multidomain spectral method for computational aeroacoustics." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0002/NQ39028.pdf.
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Muxworthy, Adrian R. "Stability of magnetic remanence in multidomain magnetite." Thesis, University of Oxford, 1998. http://ora.ox.ac.uk/objects/uuid:bc70e665-4c54-4ab5-98fa-d43ccecd07a1.
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If a rock is to retain a geologically meaningful magnetic record of its history, it is essential that it contains magnetic minerals which are capable of carrying stable magnetic remanence. Of the natural occurring magnetic minerals, magnetite is the most important because of its abundance and strong magnetic signature. The stability, i.e., the resistance to demagnetisation or reorientation, of magnetic remanence is related to grain size; in smaller grains the magnetic moments align to have single domain (SD) structures, in larger grains complex magnetic patterns are formed (multidomain (MD)). “Classical” domain theory predicts that SD remanence is stable, whilst MD remanence is not. However experimental evidence has shown that both SD and MD grains can have stable remanences. In this thesis the origin of stable MD remanence is examined. There are two opposing theories; one suggests that the stability is due to independent SD-like structures, the other postulates that the stability is due to metastable MD structure. A series of experiments were designed to examine the stability using a selection of characterised synthetic and natural samples. Low-stress hydrothermal recrystallised samples where grown for this study. For the first time, the stability of thermoremanence induced in hydrothermal crystals to cooling was examined. The results agree with previous observations for crushed and natural magnetites, and support kinematic models. The behaviour of SIRM and thermoremanences in MD magnetite to low-temperature cooling to below the crystallographic Verwey transition at 120-124 K (Tv) and the cubic magnetocrystalline anisotropy isotropic point (Tk) at 130 K was investigated. On cooling through Tv, SIRM was observed to decrease and demagnetise, however thermoremanence was found to display a large increase in the magnetisation at Tv, which was partially re- versible on warming. The size of the anomaly is shown to be dependent on the temperature at which the thermoremanence is acquired, internal stress and grain size. The anomaly is attributed to the large increase in the magnetocrystalline anisotropy which occurs on cooling through Tv . It is postulated that low-temperature cycling demagnetisation is due to kinematic processes which occur on cooling between room temperature and Tk. Characterisation of low-temperature treated remanence and partially alternating field demagnetised remanence, suggest that the stable remanence is multidomain. Low-temperature cooling of remanence in single sub-micron crystals was simulated using micromagnetic models. The models predict the observed anomaly for thermoremanence on cooling through Tv, and also the relative behaviour of SIRM and thermoremanence. The single domain threshold was calculated for the low-temperature phase of magnetite, and was found to be 0.14 microns, compared to 0.07 microns at room temperature.
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Rasheed, Mohsin. "Identity Federation Using Multidomain Authentication in PKI." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-177366.
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Today’s enterprises are facing some basic business challenges for which identity federation solutions are uniquely suited. Most online applications and ecommerce incorporate partner integration that provides to the user secure access to the partner’s site without needing to sign-on again. Additionally, organizations must provide these SSO services without having to add large numbers of users to an enterprise directory or having to manage those identities over time. A trust mechanism must exist in order to allow users who are authenticated in one domain to be trusted in a another domain. Finally, these technical challenges must be managed within the constraints of existing business and legal agreements that define thresholds for acceptable use, risk and indemnification. [14] The purpose of this thesis is to model a framework and to suggest the requirements needed of the Public Key Infrastructure for the multiple domain interoperability. This model describes the relationship between certificate authorities for establishing the trust mechanism through the techniques which are described in details of the design model description.
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Sasai, Masaki, and Kazuhito Itoh. "Cooperativity, connectivity, and folding pathways of multidomain proteins." National Academy of Sciences, 2008. http://hdl.handle.net/2237/20615.
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Chamberlain, Dean. "Expression and structural studies of multidomain proteins and complexes." Thesis, University College London (University of London), 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314366.
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Aslam, Mohammed. "Structural studies of SCR domains in multidomain complement proteins." Thesis, University College London (University of London), 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.404316.
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Randles, Lucy Gaynor. "Studies of multidomain proteins : effects of force and mutation." Thesis, University of Cambridge, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.611887.
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Mantar, Haci Ali Chapin Stephen J. Hwang Junseok. "A scalable resource management framework for QoS-enabled multidomain networks." Related Electronic Resource: Current Research at SU : database of SU dissertations, recent titles available full text, 2003. http://wwwlib.umi.com/cr/syr/main.
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Amigo, Maria Isabel. "Technological and Economic Aspects for Quality of Service in Multidomain Alliances." Télécom Bretagne, 2013. http://www.telecom-bretagne.eu/publications/publication.php?idpublication=14076.
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La mise en place de services réseau avec qualité garantie en interdomaine soulève de nombreux défis qui vont bien au-delà des seuls aspects techniques. De fait, les problèmes concernent bien sûr des aspects techniques comme l'établissement de chemins avec qualité garantie de bout en bout et l'interopérabilité des différents domaines, mais également des aspects économiques voir même culturels ou politiques. Dans cette thèse l'ambition est de traiter de la qualité de service en interdomaine d'une manière holistique, en prenant en compte certains aspects techniques mais aussi les aspects économiques de ce sujet. Nous nous intéressons d'abord à un problème technique soulevé par la mise en place de chemins avec qualité de service en interdomaine. Puis nous traitons de problématiques économiques, en considérant les conflits d'intérêts entre différents acteurs comme les fournisseurs de services de réseau (Network Service Provider) qui doivent collaborer pour fournir une qualité de bout en bout, et les acheteurs de chemins avec qualité garantie. Cas acheteurs sont typiquement des diffuseurs utilisant les services d'opérateurs de réseaux (Over the Top). Ensuite nous adoptons une approche plus holistique en considérant les interactions entre la couche de mesure de la qualité de service et la couche économique, et les effets que les décisions économiques ont sur le comportement des acheteurs. Plus précisément, nous proposons un schéma de tarification pour la vente de services avec qualité qui est simple et nous l'étudions en détail. Ce schéma propose de faire la vente des services en utilisant les enchères de premier prix et en assurant l'acheteur d'être remboursé d'un certain pourcentage du prix payé pour le service si la qualité de service n'est pas atteinteProviding end-to-end quality-assured services implies many challenges, which go beyond technical ones, involving as well economic and even cultural or political issues. In this thesis we first focus on a technical problem and then intent a more holistic regard to the whole problem, considering at the same time Network Service Providers (NSPs), stakeholders and buyers' behaviour and satisfaction. One of the most important problems when deploying interdomain path selection with Quality of Service (QoS) requirements is being able to rely the computations on metrics that hold for a long period of time. Our proposal for solving that problem is to compute bounds on the metrics, taking into account the uncertainty on the traffic demands. We then move to a NSP-alliance scenario, where we propose a complete framework for selling interdomain quality-assured services, and subsequently distributing revenues. At the end of the thesis we adopt a more holistic approach and consider the interactions with the monitoring plane and the buyers' behaviour. We propose a simple pricing scheme and study it in detail, in order to use QoS monitoring information as feedback to the business plane, with the ultimate objective of improving the seller's revenue
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Tilford, Timothy James. "Numerical analysis of microwave processing problems using a multidomain solver approach." Thesis, University of Greenwich, 2013. http://gala.gre.ac.uk/11941/.
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This work outlines the process undertaken in the formulation and validation of a numerical model for analysis of practical microwave processing problems. The proposed model adopts a novel multi-domain Eulerian-Lagrangian approach to the problem, defining two discrete numerical domains coupled through a set of data transfer algorithms. One of the numerical domains is defined for analysis of electromagnetic field distribution while the other is used for analysis of the thermophysical aspects of the problem. The thermophysical domain is restricted to the load being processed and is discretised in an Eulerian manner using an unstructured mesh for solution using a finite volume approach. The electromagnetic domain is discretised using a tensor-product rectilinear structured mesh for solution of Maxwell’s equations using a Yee finite difference time domain approach. The thermophysical load is represented within the electromagnetic domain through a mapped Lagrangian complex permittivity distribution rather than being defined explicitly. The two domains are coupled through mapping routines capable of defining the complex permittivity distribution within the electromagnetic domain and transferring the calculated power density distribution into the thermophysical domain. This interdomain coupling allows the meshes in the two domains to be non coincident, enabling the discretisation of the two domains to be completely independent of each other. This approach to analysis of coupled microwave processing problems is novel and provides a number of significant benefits over conventional single-domain methods. The primary benefit of the approach is that the electromagnetic and thermophysical parts of the analysis can be handled by different solvers using differing meshes. This is a very significant advance as the optimal approach to solving one of the parts be be extremely inefficient or indeed unfeasible for the other. The approach allows electromagnetic fields irradiating complex geometries placed inside a rectilinear microwave ovens to be analyses using a tensor product solver. The solution of the electromagnetic field distribution is typically the most computationally expensive part of a coupled solution of microwave heating. The ability to use a Yee finite difference solver rather than a conformal FDTD or finite element approach provides a very significant reduction in computational expense, enabling more complex analyses to be performed. Solution of thermophysical aspects of the problem are most effectively tackled using an unstructured spatial discretisation in cases with complex geometries. The adoption of an unstructured finite volume approach for the thermophysical part of the analysis provides an analysis capability far beyond that of the finite difference approach typically used in analyses with a finite difference electromagnetic solver. Further benefits stem from the inherent capability to alter the discretisation of the electromagnetic domain independently of the thermophysical domain, enabling cases with advection and/or rotation of the load within the oven to be considered with relative ease. Analysis of this type of problem is highly complex when using a single domain approach as the mesh needs to be redefined at regular interval during the solution. The capability to refine the discretisation of the electromagnetic domain also improves efficiency in cases where dielectric properties vary significantly during the process as mesh resolution can be varied as the process progresses. The primary drawback with the adoption of the multidomain approach is that the load is represented in the electromagnetic domain as a mapped Langrian complex permittivity distribution rather than being explicitly defined as part of the domain discretisation. There are therefore issues relating to the smearing of material boundaries which may influence wave scattering across the boundary adversely affecting accuracy of the electric field solution. In order to study the efficiency and accuracy of the approach a series of tests were conducted to assess the performance of each individual component of the analysis framework to ensure that these had been implemented effectively and to determine the magnitude of any apparent errors. The model was subsequently applied to a simple test case to ensure that the components were coupled in an effective manner. This test and validation process showed that individual components to be accurate and fit for purpose with errors due to data transfer between the two computational domains shown to be small. The results obtained from the validation case agreed relatively closely with experimental data demonstrating the implementation and efficacy of the model. The model was subsequently validated against two practical microwave processing problems - thawing of food within a domestic microwave oven and polymer curing using a dual-section microwave system. In the food thawing study, the solution obtained by the numerical model was validated against data obtained during an experimental study. The study was intended to meet the requirements of an industrial partner in research work that eliminated a range of simplifications adopted in alternate studies. The analysis therefore focussed on thawing of a challenging ’real-world’ material, placed in a complex shaped container. The load was placed on the rotating turntable of a domestic microwave oven. Results obtained from the numerical simulations agree moderately well with experimentally derived data. Primary disparities between experimental data and numerical solutions would appear to stem from inaccuracies in modelling the solid-liquid phase change in a complex multi-component material coupled with the very significant variation in dielectric loss over the melting temperature range. The microelectronics study focussed on curing of polymer materials in a microelectronics package using a dual-section microwave oven system. The requirement for this study was to predict the optimal process parameters for operation of the system. Numerical assessment of the development of key variables such as temperatures, degree of cure and stresses during the process was critical to this problem. Experimental measurements of these parameters during microwave processing were not feasible. Numerical comparisons of the microwave system with a conventional convection oven process have additionally been carried out. Key results from the study include optimal temperature profiles, final degree of cure distribution and residual stress magnitudes. Numerical data from the analyses are being integrated into an experimental study as part of ongoing work. An overall assessment of the numerical approach would indicate that it is a viable method of efficiently obtaining solutions to practical microwave processing problems. Further research is required to assess the influence of the smeared dielectric boundary in the finite difference solver on reflection, refraction and focussing effects on the accuracy of the numerical solution.
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Hanley, Patrick. "A multidomain pseudospectral solution for the general-frequency unsteady transonic small disturbance equation." Thesis, Massachusetts Institute of Technology, 1988. http://hdl.handle.net/1721.1/39019.
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Vlachakis, Natalie. "Studies towards the development of methods to select stable fragments from multidomain proteins." Thesis, University of Sussex, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.413311.
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Boutigny, François. "Multidomain virtual network embedding under security-oriented requirements applied to 5G network slices." Electronic Thesis or Diss., Institut polytechnique de Paris, 2019. http://www.theses.fr/2019IPPAS002.
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La 5G apporte un nouveau concept, le network slicing (découpage du réseau en tranches). Cette technologie permet de généraliser le modèle économique des MVNO à des entreprises qui ont besoin d’opérer un réseau, sans que cela ne soit leur cœur de métier. Chaque tranche (slice) est un réseau virtuel de bout en bout, dédié et personnalisé, au-dessus d’une infrastructure partagée ; cette infrastructure elle-même être fournie par l’interconnexion de fournisseurs d’infrastructure: nous parlons dans ce cas d’infrastructure multi-domaine.L’objectif de cette thèse est d’étudier l’allocation de ces tranches dans une telle infrastructure multi-domaine. Le problème est connu comme l’incorporation de réseau virtuel (Virtual Network Embedding (VNE)). Il s’agit d’un problème NP-difficile. Pratiquement, le problème VNE recherche à quelles ressources physiques associer un ensemble d’éléments virtuels. Les ressources physiques décrivent ce qu’elles peuvent offrir. Les éléments virtuels décrivent ce qu’ils exigent. La mise en relation de ces offres et de ces demandes est la clé pour résoudre le problème VNE.En l’espèce, nous nous sommes intéressés à la modélisation et à la mise en place d’exigences de sécurité. En effet, nous nous attendons à ce que les acteurs à l’initiative des tranches appartiennent à des sphères éloignées des télécommunications. Or de la même façon qu’ils connaissent peu ce domaine, nous pouvons nous attendre à ce que leurs besoins, notamment de sécurité, s’expriment d’une façon sans précédent dans le contexte des tranches.Cette thèse présente un algorithme capable de traiter des exigences variées selon un modèle extensible fondé sur un solveur de satisfiabilité appliqué à des théories décidables (Satisfiability Modulo Theories (SMT)). Comparée à la programmation linéaire (Integer Linear Programming (ILP)), plus commune dans le domaine des VNE, cette formulation permet d’exprimer les contraintes à satisfaire de façon plus transparente, et d’auditer l’ensemble des contraintes.De plus, ayant conscience que les fournisseurs d’infrastructure sont réticents à exposer les informations relatives à leurs ressources physiques, nous proposons une résolution limitant cette exposition. Ce système a été implémenté et testé avec succès au cours du doctorat5G brings a new concept called network slicing. This technology makes it possible to generalize the business model of MVNOs to companies in need to operate a network, without it being their core business. Each slice is an end-to-end, dedicated and customized virtual network, over a shared infrastructure; this infrastructure itself is provided by the interconnection of infrastructure providers: we refer to this case as a multi-domain infrastructure.The objective of this thesis is to study the allocation of these slices in such a multi-domain infrastructure. The problem is known as Virtual Network Embedding (VNE). It is an NP-hard problem. Practically, the VNE problem looks for which physical resources to associate a set of virtual elements. Physical resources describe what they can offer. Virtual elements describe what they require. Linking these offers and requests is the key to solve the VNE problem.In this thesis, we focused on modeling and implementing security requirements. Indeed, we expect that the initiators of the slices belong to areas distant from telecommunications. In the same way that they know little about this field, we can expect that their needs, especially in security, are novel in the slice context.This thesis presents an algorithm able to handling various requirements, according to an extensible model based on a Satisfiability Modulo Theories (SMT) solver. Compared to Integer Linear Programming (ILP), more common in the VNE field, this formulation allows to express the satisfaction constraints in a more transparent way, and allows to audit all the constraints.Moreover, being aware that infrastructure providers are reluctant to disclose information about their physical resources, we propose a resolution limiting this disclosure. This system has been successfully implemented and tested during the Ph.D
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Huang, Shuo. "A New Multidomain Approach and Fast Direct Solver for the Boundary Element Method." University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1505125721346283.
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Toloczko, Felipe Ribeiro. "Análise do comportamento mecânico de ligas metálicas submetidas ao processo superplástico em matriz multidomo." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/3/3151/tde-28092016-104437/.
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Este trabalho trata da avaliação da técnica de conformação por expansão fluidostática (bulge forming) através de uma matriz com múltiplas cavidades. Duas ligas de especificação AA5083 e Pb-60Sn foram submetidas ao processo de superplasticidade (Superplastic Forming) para a verificação de diferentes parâmetros de trabalho e comparação com os resultados por simulação numérica. Uma das principais conclusões obtidas é que o método multidomo foi válido para o estudo do fenômeno superplástico. Os testes foram realizados através do método de pressão constante, onde foi possível obter variáveis como tensão, taxa de deformação e índice de sensibilidade a taxa de deformação. Uma importante implicação deste processo é o controle correto do tempo de trabalho com cavidades conformadas em ensaios distintos.This study aims to evaluate the forming technique fluidostatic expansion (bulge forming) through a die with multiple cavities. Two AA5083 alloy and Pb-60Sn specification were submitted to superplasticity process (superplastic forming) for checking different working parameters and comparison with the results in numerical simulation. One of the main conclusions is that the multidomo method was valid to study the superplastic phenomenon. The tests were performed using the constant pressure method, where it was possible to obtain variables such as stress, strain rate and the strain rate sensitivity index. An important implication of this process is the correct control of working time with shaped cavities in separate trials.
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Heil, Christina Sabine [Verfasser], Martin [Gutachter] Grininger, and Michael [Gutachter] Göbel. "Towards the conformational dynamics of multidomain proteins / Christina Sabine Heil ; Gutachter: Martin Grininger, Michael Göbel." Frankfurt am Main : Universitätsbibliothek Johann Christian Senckenberg, 2019. http://d-nb.info/1198932856/34.
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Ma, Yue. "Deconstructing an iterative multidomain polyketide synthase : catalytic activity of the Aspergillus parasiticus norsolorinic acid synthase." Thesis, University of Bristol, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.443679.
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Sjöström, Tomas. "Discrete time variational mechanics of multidomain systems : Applications to coupled electronic, hydraulic, and multibody systems." Thesis, Umeå universitet, Institutionen för fysik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-61701.
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Today there exist few non-smooth multi-domain simulation tools using time-discretized Lagrangian mechanics for circuits.The main goal is to show that itis possible to use a semi-implicit, parameter free non-smooth variational timestepper to simulate the circuits with time-steps proportional to the system timescales.This is demonstrated by implementing and performing extensive numericaltests for various types of electrical, mechanical and hydraulic components anddemonstrate that the components are stable, with the correct behavior whenthe system is solved using a modified block pivot solver.Simulation results shows that piecewise linear models are enough for thesimple switching circuits in this thesis.Idag finns det få simulatorer för icke-släta multidomän kretsar som bygger på tidsdiskretisering av Lagranges ekvationer. Huvudmålet är att visa att det är möjligt att använda en semi-implicit, parameter fri icke-slät diskret lösare för att simulera kretsar med tidssteg proportionella mot systemens tidsskalor. Detta visas genom att implementera olika typer av elektriska, mekaniska och hydrauliska komponenter samt att visa att komponenterna är stabila och har rätt beteende när systemet simuleras av en modifierad block pivot lösare. Simulerings resultaten visar att icke-släta Newton metoder med styckvis-linjära komponenter och komplementära villkor är tillräkligt för att simulera brytande komponponenter i de simulerande kretsarna.
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Queiroz, Eduardo Martinelli Galvão de. "Redes ópticas multidomínio: métodos de escolha de nós de borda e algoritmo de roteamento de tráfego." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/18/18155/tde-05102012-091145/.
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A crescente demanda de tráfego em redes de acesso pressiona a melhor utilização das redes backbone, que são utilizadas para transporte de grandes taxas de dados em diversos domínios (Sistemas Autônomos, SAs). Com o aumento destas redes, aumenta-se a complexidade de topologia das interligações entre domínios. Desta maneira, roteamento de tráfego e pontos de interconexão de SAs (nós de borda) são questões importantes para o desempenho destas redes, que são operadas por diversos provedores que podem utilizar protocolos de comunicação distintos. Neste sentido, o roteamento interdomínio apresenta desafios como a publicação ou não de informações de parâmetros de rede de SAs e como tratar esta questão de maneira globalizada, com novos protocolos e suas especificações. Em termos de pontos de interconexão de SAs, a especificação dos locais onde enlaces inter-redes são conectados aos domínios são importantes para seu desempenho, já que são responsáveis por toda troca de tráfego entre redes distintas. O trabalho considera redes ópticas opacas e translúcidas em cenário multidomínio com bandas multigranulares. Neste cenário é estudado um algoritmo de roteamento multidomínio. No trabalho também é feito um planejamento, especificando em quais nós serão conectados enlaces interdomínio. A principal contribuição deste trabalho é o estudo de planejamento de enlaces interdomínio, com a proposta de um método para escolha de nós de borda (sistematização), com objetivo de diminuir a probabilidade de bloqueio interdomínio. A sistematização é baseada em estudos de resultados de algoritmo genético desenvolvido para o mesmo propósito e sua utilização diminui em até 42% o bloqueio interdomínio. Um algoritmo de alocação de banda também foi desenvolvido para redes multidomínio, que considera parâmetros da camada de rede e óptica para o cálculo de peso de enlaces para encontrar caminhos ópticos entre nós fonte e destino. Os resultados mostram diminuição de até 35% no bloqueio interdomínio com a modificação feita em algoritmo proposto na literatura.The huge demand for traffic in last mile networks push the better utilization of backbone networks, which are used to transport large data rates in several domains (Autonomous Systems, ASs). With this growth, the topology complexity of interdomain links increases. Then, traffic routing and interconnection points of ASs (border nodes) are relevant questions for the performance of these networks, which are managed by several providers that can use distinct communications protocols. Thus, the interdomain routing presents challenges such as the decision on publishing or not the network´s parameters from ASs and how to deal with this issue in a global way, with new protocols and its specifications. For interconnection points between ASs, the points where interdomain links are connected are important for their performances, since they are responsible for all traffic exchange between distinct networks. This work considers opaque and translucent optical networks in a multidomain scenario with multigranular data rates. In this scenario a multidomain routing algorithm is studied and a network planning is developed, specifying the nodes where interdomain links are connected. The main contribution of this work is the planning of interdomain links, with the proposal of a method for border nodes selection (systematization), with the objective of decreasing the interdomain blocking probability. The systematization is based on the results from a genetic algorithm developed for the same purpose and its utilization decrease up to 42% of the interdomain blocking. A bandwidth allocation algorithm was also created for multidomain scenarios, that considers parameters from network and optical layer for the link weight calculation in order to find optimal paths. The results show a decreasing of up to 35% for interdomain blocking with a contribution based on literature\'s work.
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Chalkia, Dimitra Nei Masatoshi. "Origins and evolution of three multidomain gene families concerned with basic cellular and developmental processes in eukaryotes." [University Park, Pa.] : Pennsylvania State University, 2008. http://etda.libraries.psu.edu/theses/approved/WorldWideIndex/ETD-2693/index.html.
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Roca, Pinilla Ramon. "Development of a new generation of antimicrobial proteins based on a versatile nanoparticulated format and multidomain structure." Doctoral thesis, Universitat Autònoma de Barcelona, 2020. http://hdl.handle.net/10803/670790.
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Durant la major part de la historia humana, els patògens han estat una de les principals causes de morts i malalties. Gràcies al descobriment dels antibiòtics hem aconseguit tractar aquestes malalties amb facilitat, però el seu mal ús ha accelerat l’aparició de resistències als antimicrobians (AMRs). Atès que les AMRs han provocat que la majoria de fàrmacs antimicrobians siguin ineficaços, el desenvolupament de tractaments alternatius és mes necessari que mai. Els pèptids de la defensa del hoste (HDPs) han estat proposats com a models per la generació de nous antimicrobians per lluitar contra les infeccions AMR. Tot i així, la majoria d’HDPs és produeixen mitjançant la síntesi química, un procés que és car, insostenible i difícil d’escalar. Alternativament, la producció recombinant d’HDPs és molt atractiva però complicada, ja que són pèptids altament susceptibles de ser degradats i són tòxics per l’hoste recombinant. Malgrat això, els cossos d’inclusió (IBs), que són agregats de proteïna formats durant els processos de producció recombinant, es poden utilitzar com a format alternatiu al de la proteïna soluble per permetre la producció d’HDPs dins l’hoste sense efectes tòxics. D’altra banda, la construcció de proteïnes quimèriques podria ser una estratègia per expressar pèptids petits amb èxit. En aquest context, aquesta tesi explora diverses estratègies per la producció recombinant d’HDPs. Per una banda, hem explorat l’ús de les cremalleres de leucina com a dominis potencials per fomentar la producció recombinant d’HDPs en la fracció insoluble i per augmentar la qualitat de la proteïna recombinant dels IBs. A més a més, hem desenvolupat diverses proteïnes antimicrobianes multidomini basades en la fusió de diferents pèptids HDP i proteïnes de la immunitat innata. Com que també hem utilitzat cremalleres de leucina en aquests constructes, es poden expressar de manera efectiva – sense toxicitat per la cèl·lula productora. A més, en cas de necessitat, podem recuperar antimicrobians solubles a partir dels IBs gràcies a un protocol de solubilització suau i no desnaturalitzant. En conjunt, hem demostrat que aquests constructes tenen un ampli espectre d’acció antimicrobiana contra bacteris multi resistents (MDR), tant en el format soluble com en el format d´IB. És més, els constructes també són capaços d’estimular l’alliberament de IL-8 dins d’un potencial rang de propietats immunomoduladores. Aquests resultats ens han convidat a utilitzar les nostres proteïnes en la biofuncionalització de monocapes autoacoblants per evitar la formació de biofilms, i hem observat que aquestes proteïnes poden ancorar-se a aquests materials i evitar el creixement de biofilms. En resum, aquests resultats reforcen les proteïnes antimicrobianes multidomini com a potencials alternatives antimicrobianes amb propietat immunomoduladores.Durante la mayor parte de la historia humana, los patógenos han sido una de las principales causas de muertes y enfermedades. Gracias al descubrimiento de los antibióticos hemos conseguido tratar estas enfermedades con facilidad, pero su mal uso ha acelerado la aparición de resistencias a los antimicrobianos (AMRs). Dado que las AMRs han provocado que la mayoría de fármacos antimicrobianos sean ineficaces, el desarrollo de tratamientos alternativos es más necesario que nunca. Los péptidos de la defensa del huésped (HDPs) han sido propuestos como modelos para la generación de nuevos antimicrobianos para luchar contra las infecciones AMR. Sin embargo, la mayoría de HDPs se producen mediante la síntesis química, un proceso que es caro, insostenible y difícil de escalar. Alternativamente, la producción recombinante de HDPs es muy atractiva pero complicada, ya que son péptidos altamente susceptibles de ser degradados y son tóxicos para el huésped recombinante. Sin embargo, los cuerpos de inclusión (IBs), que son agregados de proteína formados durante los procesos de producción recombinante, se pueden utilizar como formato alternativo al de la proteína soluble para permitir la producción de HDPs dentro del huésped sin efectos tóxicos. Por otra parte, la construcción de proteínas quiméricas podría ser una estrategia para expresar péptidos pequeños con éxito. En este contexto, esta tesis explora diversas estrategias para la producción recombinante de HDPs. Por un lado, hemos explorado el uso de las cremalleras de leucina como dominios potenciales para fomentar la producción recombinante de HDPs en la fracción insoluble y para aumentar la calidad de la proteína recombinante en los IBs. Además, hemos desarrollado varias proteínas antimicrobianas multidominio basadas en la fusión de diferentes péptidos HDP y proteínas de la inmunidad innata. Como también hemos utilizado cremalleras de leucina en estos constructos, se pueden expresar de manera efectiva - sin toxicidad para la célula productora. Además, en caso de necesidad, podemos recuperar antimicrobianos solubles a partir de los IBs gracias a un protocolo de solubilización suave y no desnaturalizando. En conjunto, hemos demostrado que estos constructos tienen un amplio espectro de acción antimicrobiana contra bacterias multi resistentes (MDR), tanto en el formato soluble como en el formato de IBs. Es más, los constructos también son capaces de estimular la liberación de IL-8 dentro de un potencial rango de propiedades inmunomoduladoras. Estos resultados nos han invitado a utilizar nuestras proteínas en la biofuncionalizacón de monocapas autoensamblantes para evitar la formación de biofilms, y hemos observado que estas proteínas pueden anclarse a estos materiales y evitar el crecimiento de biofilms. En resumen, estos resultados refuerzan las proteínas antimicrobianas multidominio como potenciales alternativas antimicrobianas con propiedades inmunomoduladoras.
For most of human history, pathogens have been a leading cause of death and illness. Although we have attained the ability to treat them easily, thanks to the discovery of antibiotics, the widespread overuse and misuse of antimicrobial drugs have accelerated the appearance of antimicrobial resistances (AMRs). Because AMRs have rendered most antimicrobial drugs ineffective, the development of alternative approaches is more necessary than ever before. Host defense peptides (HDPs) have been proposed as blueprints for the generation of new antimicrobials to fight AMR infections. Despite this, most HDPs are produced by chemical synthesis, which is expensive, unsustainable, and difficult to scale-up. Alternatively, their recombinant production is very appealing but still challenging. HDPs are highly susceptible to degradation and are generally toxic to the recombinant host. However, inclusion bodies (IBs), which are protein aggregates that usually happen during recombinant production, can be used to allow HDP formation inside the host without being harmful. Also, the construction of chimeric proteins could be a strategy for successful recombinant expression of small peptides. In this context, this dissertation explores several new strategies for the recombinant production of HDPs. We tried leucine zippers as potential domains to drive the recombinant production of HDPs to the insoluble fraction and improve IBs protein quality. After that, we developed several antimicrobial multidomain proteins based on the fusion of different peptides and proteins from innate immunity. Because we also used leucine zippers with these constructs, they could be produced effectively – without toxicity to the microbial cell factory. Moreover, when needed, we were able to recover soluble antimicrobials from IBs using a mild, non-denaturing protocol. Overall, we demonstrated that these constructs have a broad-spectrum antimicrobial action against multi-drug resistant (MDR) bacteria, in both the soluble and IB format, and that they could trigger the release of IL-8 within a range of potential immunomodulatory properties. These outcomes invited us to use our constructs in the biofunctionalization of self-assembled monolayers to avoid biofilm formation. We observed that the chimeric proteins could be anchored to these materials and avoid biofilm growth. In sum, these results reinforce multidomain antimicrobial proteins as potential antimicrobial alternatives with immunomodulatory properties and open up the possibility for many applications of this new generation of antimicrobial protein nanoparticles as well as their soluble analogs.
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Emmert, Thomas. "Development of a multidomain high-order algorithm for computational aeroacoustics : Application to subsonic and transonic confined flows." Ecully, Ecole centrale de Lyon, 2007. http://www.theses.fr/2007ECDL0030.
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Un nouvel algorithme de simulation numérique pour l'aeroacoustique, SAFARI (Simulation Aeroacoustique des Fluides Avec Résonances et Intercations), a été développé pour le calcul direct du bruit. Il s'appuie sur la résolution des équations de Navier-Stokes compressibles en coordonnées curvilignes. Des schémas aux différences finies d'ordre élevé sont implémentés. La solution est calculée sur des maillages recouvrants (méthode Chimère) pour traiter des géométries complexes. L'interpolation entre les maillages est éffectuée par des polynômes de Lagrange également d'ordre élevé. De plus chauqye maillage est découpé en blocs pour permettre l'exécution du calcul sur des machines parallèles le solveur est parallélisé à l'aide de la bibliothèque MPI. Afin d'assurer la capture des chocs forts, un filtre non linéaire de type Jameson est utilisé. SAFARI est d'abord confronté à des cas-test simples : âr exemple en 1-D l'écoulement dans une tuyère convergente/divergente ou en 2-D l'écoulement à bas nombre de Reynolds autour d'un cylindre. Les cas tests montrent que l'algorithme produit des résultats de haute précision et est bien adapté pour des calculs aéroacoustiques. Ensuite, les simulations en 3-D de deux cas d'intérêt industriel sont présentées. D'abord un écoulement à un nombre de Reynolds élevé et à un nombre de Mach modéré affleurant une cavité confinée a été stimulé. Pour des cavités confinées les modes de cavité peuvent se coupler avec les modes de résonance de la veine et produire des oscillations de grane amplitude. La calcul met clairement ce couplage en évidence. La deuxième application industrielle traitée dans le cadre de ce travail est la simulation d'un écoulement transsonique au travers d'un élargissement brusque dans un conduit plan. En fonction de la pression en aval, différets rgimes d'écoulements s'établissement dans le tuyau. Pour des pressions faibles, l'écoulement est supersonique dans le tuyau et un système de chocs obliques s'établit. Pour des pressions plus élevées, un choc droit oscillant apparaît dans l'écoulement. Les oscillations de ce choc se couplent avec les modes acoustiques longitudinaux du tuyau. Pour des pressions en aval encore plus élevées, le jet recolle sur une des parois inferieure ou superieure et des cellules des chocs sont observées. Les résultats présentés dans ce travail reproduisent tous les aspects de ce type découlement.
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Träger, Mario [Verfasser], Gunter [Akademischer Betreuer] Fischer, Thomas [Akademischer Betreuer] Kiefhaber, and Holger [Akademischer Betreuer] Barth. "Biochemie und Protein-Protein-Interaktionen des Multidomänen-Cyclophilins Cyp58 / Mario Träger. Betreuer: Gunter Fischer ; Thomas Kiefhaber ; Holger Barth." Halle, Saale : Universitäts- und Landesbibliothek Sachsen-Anhalt, 2015. http://d-nb.info/107021888X/34.
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Moritz, Bodo [Verfasser], Antje [Akademischer Betreuer] Ostareck-Lederer, Hauke [Akademischer Betreuer] Lilie, and Michael [Akademischer Betreuer] Sattler. "Argininmethyliertes hnRNP K - Synthese und kombinatorische Multidomänen-Nukleinsäure-Assoziation / Bodo Moritz. Betreuer: Antje Ostareck-Lederer ; Hauke Lilie ; Michael Sattler." Halle, Saale : Universitäts- und Landesbibliothek Sachsen-Anhalt, 2014. http://d-nb.info/1065670079/34.
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Budaker, Bernhard Verfasser], and Alexander [Akademischer Betreuer] [Verl. "Auslegung von Multidomänen-Systemen - Analyse, Modellierung und Realisierung von mechatronischen Systemen am Beispiel einer aktiven Knieprothese / Bernhard Budaker. Betreuer: Alexander Verl." Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2013. http://d-nb.info/1030266700/34.
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Honorato, Rodrigo Vargas. "Implementação de uma abordagem híbrida utilizando modelagem comparativa e ab initio para predição de estruturas tridimensionais de proteínas contendo múltiplos domínios com conectores flexíveis." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/95/95131/tde-04012016-152835/.
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Domínio proteico é uma sequência de aminoácidos evolutivamente conservada e funcionalmente independente. Um dos aspectos mais importantes do estudo de uma proteína que contem múltiplos domínios é o entendimento da comunicação, entre os diferentes domínios, e seu papel biológico. Essa comunicação em maior parte é feita pela interação direta entre domínios. A interação poderia ser tratada como uma clássica interação proteína-proteína. Entretanto, proteínas multidomínio possuem restrições determinadas por suas regiões conectoras. Os conectores interdomínio impõem restrições e limitam espaço conformacional dos domínios. Apresentamos aqui o MAD, uma rotina capaz de obter modelos tridimensionais de alta resolução para proteínas, contendo qualquer número de domínios, a partir de sua sequencia primária. Os domínios conservados são identificados utilizando a base de domínios conservados (CDD) e seus limites são utilizados para definir as regiões conectoras. É criado um ensamble de possíveis dobramentos dos conectores e sua distribuição de distâncias C/N-terminais são utilizadas como restrição espacial na busca pela interação entre os domínios.Os modelos dos domínios são obtidos por uma modelagem comparativa. Foi implementada uma heurística, capaz de lidar com a natureza combinatorial dos múltiplos domínios e com a necessidade imposta pela limitação computacional de realizar o docking dos domínios em forma de pares. Todas combinações de domínios são submetidas as rotinas de docking. Aplica-se filtro de distância e energético, excluindo as conformações que apresentam distância C/N-terminal entre domínios maior do que o valor máximo observado no ensamble de conectores e seleciona as conformações energeticamente mais favoráveis. As conformações são submetidas a uma rotina de agrupamento hierárquico baseada em sua similaridade estrutural. Para a segunda fase as conformações selecionadas são pareadas com seu domínio complementar e ressubmetidas a rotina de docking até que todas as fases tenham sido completadas. Foi criado um conjunto de testes a partir do Protein Data Bank contendo 54 proteínas multidomínio para que a rotina de docking do MAD fosse comparada com outros softwares utilizados pela comunidade cientifica, mostrou-se superior ou equivalente aos métodos testados. A capacidade de utilizar dados experimentais foi demostrada através da proposição de um modelo da forma ativa da enzima tirosina fosfatase 2, nunca observado experimentalmente. A rotina de docking foi expandida paralelamente em uma aplicação standalone e utilizada na resolução de diversos problemas biológicos. Concluímos que a inovação metodológica proposta pelo MAD é de grande valia para a modelagem molecular e tem potencial de gerar uma nova perspectiva a respeito da interação de proteína multidomínio, visto que é possível analisar essas proteínas em sua plenitude e não como domínios separados.Protein domain is an evolutionary conserved and functionally independent amino acid sequence. One of the most important aspects of the study of a protein that contains multiple domains is the understanding of communication between the different areas, and their biological role. This communication is made mostly by direct interaction between domains. The interaction could be treated as a classical protein-protein interaction. However, multidomain proteins have certain restrictions for its connector regions. The intra connectors impose restrictions and limit conformational space of the domains. We present the MAD, a routine able to get three-dimensional models of high-resolution protein, containing any number of domains, from its primary sequence. The conserved domains are identified using the basic conserved domains database (CDD) and its boundaries are used to define the connector regions. This creates a ensemble of possible folding of the connectors and distribution of distances C/N-terminals are used as spatial restriction in the search for interaction between domains.Os models of the domains are obtained by comparative modelling. A heuristic able to handle the combinatorial nature of the multiple areas and the need imposed by the computer to perform the limitation of the docking areas as pairs was implemented. All combinations of domains are referred to the docking routines. Distance and energy filters are applied, excluding conformations that have C/N-terminal domains distances larger than the maximum value observed in the connectors ensemble and selects the most favourable energy conformations. Conformations are subjected to hierarchical clustering routine based on their structural similarity. For the second phase, the selected conformations are paired with its complementary domain and resubmitted to the docking routine until all phases have been completed. A test set has been created from the Protein Data Bank containing 54 multidomain proteins so that the docking routine of MAD could be compared with other software used by the scientific community, it has been shown to be superior or equivalent to the tested methods. The ability to use experimental data was demonstrated by proposing a model of the active form of tyrosine phosphatase enzyme 2, never observed experimentally. The docking routine was expanded in a standalone application and used in solving various biological problems. We conclude that the methodological innovation proposed by the MAD is very useful for molecular modelling and has the potential to generate a new perspective on multidomain protein interaction as you can analyse these proteins in its entirety and not as separate domains.
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Sánchez, Rico Carolina [Verfasser], Michael [Akademischer Betreuer] Sattler, Friedrich [Gutachter] Förster, Bernd [Gutachter] Reif, and Michael [Gutachter] Sattler. "Conformational Dynamics and Mechanisms of RNA Recognition by the Multidomain Splicing Factor U2AF / Carolina Sánchez Rico ; Gutachter: Friedrich Förster, Bernd Reif, Michael Sattler ; Betreuer: Michael Sattler." München : Universitätsbibliothek der TU München, 2017. http://d-nb.info/1152384074/34.
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Léger, Corentin. "Conception de protéines artificielles multidomaines." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS384.
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La création de nouvelles fonctions basées sur la reconnaissance protéique et sur l'assemblage de domaines est un enjeu majeur en biotechnologie et est un moyen de comprendre les relations structures/fonctions des protéines engagées dans des processus d'interactions. Aujourd’hui, des bibliothèques de protéines artificielles obtenues par ingénierie peuvent être sources de protéines aux propriétés de reconnaissance analogues à celles des dérivés d’anticorps.L’équipe Modélisation et Ingénierie des Protéines a ainsi construit une banque de protéines à motifs structuraux répétés appelées « alphaReps ». Les alphaReps présentent des propriétés remarquables en termes de production et de stabilité. Contrairement à la plupart des anticorps et dérivés d’anticorps, elles peuvent même s’exprimer sous forme fonctionnelle dans le cytoplasme de cellules eucaryotes. De tels objets peuvent donc maintenant être utilisés comme des briques élémentaires en vue d’une ingénierie modulaire. Ainsi la construction de nouvelles fonctions de reconnaissance optimisées tant au niveau de la spécificité que de l’affinité sera possible en réarrangeant et/ou dupliquant ces briques élémentaires.Un premier volet de ce projet de thèse a consisté à construire puis étudier les propriétés biophysiques de protéines bidomaines basées sur les alphaReps afin de mieux comprendre les comportements adoptés par de telles constructions. Outre l’aspect fondamental de cette question, cette étude donnera « les règles » pour moduler de façon contrôlée les interactions entre ces protéines. Les résultats montrent qu'il est possible de créer de nouvelles fonctions par simple ajout d'un linker entre deux alphaReps : avidité, coopérativité, changement de conformation.Dans un second temps, l’objectif a été de développer, à partir des protéines bidomaines précédemment étudiées, de nouveaux biosenseurs basés sur le FRET (Förster Resonance Energy Transfer) pouvant être utilisés in vivo et in vitro. Cette deuxième partie présente deux biosenseurs avec des limites de détection de l'ordre du nanomolaire. Les alphaReps utilisées dans ces constructions pouvant être changées en fonction de la cible souhaitée, il s'agit ici d'une preuve de concept pouvant être généralisée à n'importe quelle cible.Enfin la dernière partie de cette thèse s'est portée sur la conception et l'étude de nouveaux biosenseurs génétiquement codables. Ces biosenseurs présentent notamment l’avantage d’être utilisables immédiatement après production et ne nécessitent donc plus d’étape de couplage chimique. Les résultats obtenus montrent que la création de tels biosenseurs est possible mais qu’une optimisation reste encore nécessaire pour améliorer leur spécificité, leur stabilité et leur capacité de détectionThe creation of new protein functions based on recognition and molecular assembly is not only a major goal in biotechnology but is also a means to understand the relation structure/function of proteins involved in interaction processes. Today, libraries of artificial proteins obtained by engineering can be a source of proteins with recognition properties similar to the properties of antibodies.The team Protein Engineering and Modeling has thus created a library of proteins with structural repeats called the “alphaReps”. The alphaReps present remarkable properties in terms of production and stability. Unlike most of the antibodies and their derivatives, they can even be expressed and functional in the cytoplasm of eukaryotic cells. Such objects can therefore be used as building bricks in modular engineering. The construction of new optimized recognition functions both in specificity and in affinity can then be possible by rearranging or duplicating these elementary bricks.The first part of this thesis project consisted in the construction and study of the biophysical properties of bidomain proteins based on alphaRep in order to have a better understanding of the behaviour of such constructions. Beside the fundamental aspect of this question, this study will give the “rules” to modulate the interactions between these proteins in a controlled way. The results show that it is possible to create new functions such as avidity, cooperativity, conformational change, simply by adding a linker between two alphaReps.In a second step, the goal was to develop, with the bidomain proteins previously studied, new biosensors based on the FRET (Förster Resonance Energy Transfer) which can be used in vivo and in vitro. This second part presents two biosensors with limits of detection in the nanomolar range. Since the alphaReps used in these constructions can be changed depending on the chosen target, it is a proof of concept which can be adapted to any desired target.Finally, the third part of this thesis focused on the development of genetically codable biosensors. These biosensors have the particular advantage of being usable directly after production and therefore no longer require a chemical coupling step. The results show that the development of such biosensors is worth considering but an optimization is still required in order to improve their specificity, their stability and their detection capacity
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Audoux, Kévin. "Proposition d'un processus d'évaluation multidomaine pour améliorer la conception de produit." Thesis, Paris, ENSAM, 2019. http://www.theses.fr/2019ENAM0025/document.
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La concurrence industrielle pousse les entreprises à développer de nouveaux produits innovants. En outre, les industriels sont soumis à de plus en plus de contraintes issues des différents acteurs du processus de conception (fabricants, utilisateurs) ou liées aux évolutions de leur environnement (réglementations, technologies). Il leur est donc nécessaire d’adapter leurs activités de conception et plus particulièrement les étapes d’évaluation pour que les produits développés correspondent aux exigences multiples de toutes les parties prenantes. Ces contraintes se traduisent par l’intégration de nouveaux domaines ou l’évolution de domaines existants dans le processus de conception.Dans ce contexte, l’objectif de ces travaux de thèse est de formaliser et d’apporter des méthodes permettant l’évaluation multidomaine dans le processus de conception. Ce manuscrit s’intéresse donc à la problématique suivante : « Comment les phases d’évaluation dans un processus de conception multidomaine peuvent-elles permettre d’accroître les performances du produit à partir des représentations intermédiaires ? ». Pour cela nous proposons une méthodologie permettant d’améliorer le processus d’évaluation en créant un outil d’évaluation multidomaine et en formalisant les étapes du processus d’évaluation pour apporter des méthodes d’amélioration adaptées aux domaines concernés par le produit à concevoir. Des expérimentations sont menées afin de valider leurs apports dans le processus de conception en s’intéressant notamment à trois domaines : l’innovation, la prise en compte des impacts environnementaux et la fabrication additive. Ces expérimentations ont permis de valider la méthodologie de création de l’outil d’évaluation et l’apport des étapes d’améliorationIndustrial competition is driving companies to develop new innovative products. In addition, industrial companies are increasingly subject to constraints from the various actors in the design process (manufacturers, users) or linked to changes in their environment (regulations, technologies). It is therefore necessary for them to adapt their design activities and more particularly the evaluation steps so that the products developed correspond to the multiple requirements of all stakeholders. These constraints result in the integration of new domains or the evolution of existing domains into the design process.In this context, the objective of this thesis work is to formalize and provide methods for multidomain evaluation in the design process. This manuscript therefore addresses the following question: "How can evaluation phases in a multidomain design process help to increase the performance of intermediate representations? ». To this end, we propose a methodology to improve the evaluation process by creating a multidomain evaluation tool and formalizing the steps of the evaluation process to provide improvement methods adapted to the areas concerned by the product to be designed. Experiments are being carried out to validate their contribution to the design process, focusing in particular on three areas: innovation, taking into account environmental impacts and additive manufacturing. These experiments made it possible to validate the methodology for creating an evaluation tool and the contribution of the improvement steps
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Lazreg, Saïd. "Identification inverse d’états multiaxiaux élasto-plastiques par méthode magnétique." Thesis, Cachan, Ecole normale supérieure, 2011. http://www.theses.fr/2011DENS0021.
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Cette étude s'intègre dans le cadre d'un développement accru de nouvelles techniques de contrôle non destructif des matériaux magnétiques basées sur les phénomènes de couplage magnéto-mécanique. L'objectif est de promouvoir des méthodes originales de mesure des propriétésmagnétiques permettant d'évaluer quantitativement l'état thermo-métallurgico-mécanique d'un matériau par une simple identification inverse.Nous proposons dans ce document un modèle magnéto-mécanique couplé dit modèle multidomaine compatible avec la procédure de contrôle magnétique. Ce modèle analytique permet de simuler le comportement magnétique et magnétostrictif d'un matériau magnétique soumis à un chargement mécanique unidirectionnel. Il a montré une bonne adaptabilité à des états de contraintes et structures magnétiques variées. Le modèle multidomaine a pu être validé dans le cas d'un chargement élastique uniaxial et multixial par un simple recours à une contrainte équivalente magnéto-mécanique. Il a pu également intégrer les éléments nécessaires à la modélisation de l'influence de la plasticité sur l'état magnétique. La plasticité est introduite via un état de contrainteinterne caractérisant une structure hétérogène biphasée. Des corrélations intéressantes entre variables d'écrouissage macroscopiques et propriétés magnétiques ont été élaborées et l'approche a été validée sur un acier dual phases.Nous nous sommes enfin intéressées à a mise en place d'un protocole expérimental novateur assurant un suivi continuel du comportement piézomagnétique du matériau au cours d'un essai de fatigue. Cette technique permet d'estimer la limite d'endurance des matériaux magnétiquesThis study is within a recent research largely motivated by the possibility of development of new non-destructive techniques based on the magneto-mechanical coupling. Thus, the issue is to propose original magnetic methods allowing a quantitative evaluation of the thermo-metallurgicomechnical state of ferromagnetic materials by a simple inverse identification.We propose in this document a coupled magneto-mechanical modeling called multidomain modeling suitable for the non-destructive process. This model is able to simulate magnetic and magnetostrictive behaviors of materials submitted to an uniaxial mechanical loading. It exhibits an adaptability to various mechanical states and magnetic structures. Multidomain modeling provides good results in the case of elastic loading either uniaxial or multiaxial by the use of an equivalent stress. It can also integrate the key elements for modeling the effect of plasticity on the magneticbehavior. Plasticity is introduced through internal stress characterizing heterogenous biphasic structure. Interesting correlations between macroscopic hardening parameters and magnetic properties are shown and the plasticity approach is confirmed by experiments carried out on a dual phase steel.Finally, we propose an experimental protocol allowing in situ continuous investigation of the piezomagnetic behavior during fatigue test. This experimental technique permits the estimation of fatigue limit of ferromagnetic materials
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Silva, Júlio César da. "Estudos de macromoléculas biológicas parcialmente desestruturadas usando espalhamento de raios-X." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/277988.
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Orientador: Iris Concepción Linares de TorrianiTese (doutorado) - Universidade Estadual de Campinas, Instituto de Fisica Gleb Wataghin
Made available in DSpace on 2018-08-15T22:30:16Z (GMT). No. of bitstreams: 1 Silva_JulioCesarda_D.pdf: 7791031 bytes, checksum: 5711654f743b7d6fb045861e9239ad8c (MD5) Previous issue date: 2010
Resumo: As técnicas de caracterização estrutural de macromoléculas tradicionais se baseiam no fato de uma macromolécula possuir uma conformação compacta e estruturada. Partes flexíveis ou regiões desordenadas têm sido sempre consideradas como grandes obstáculos para técnicas como a cristalografia de raios-X e a ressonância magnética nuclear (RMN). A necessidade de entender a atividade funcional de proteínas nativamente desenoveladas e de proteínas flexíveis com múltiplos domínios tem adquirido grande importância recentemente, mesmo porque essas proteínas desafiam o paradigma de que uma proteína precisa de uma estrutura bem definida para ser funcional. É bem nesse ponto que a técnica de espalhamento de raios-X a baixos ângulos (SAXS) surge oferecendo ferramentas únicas para realizar estudos de macromoléculas flexíveis ou parcialmente desestruturadas, com aplicações muito bem sucedidas em polímeros, matéria mole e macromoléculas em solução. Neste trabalho de tese decidimos enfrentar o desafio de caracterizar proteínas que não possuem uma estrutura bem definida. A teoria do espalhamento mereceu especial cuidado para se adequar tanto aos métodos experimentais da técnica quanto aos tratamentos matemáticos em cálculos usados para estudar esse tipo de proteínas. Apresentamos aqui o estudo de duas proteínas pertencentes à classe das proteínas nativamente desenoveladas: (1) a proteína FEZ1, que é necessária para o crescimento de axônios; (2) a proteína Ki-1/57, que é encontrada em diversas células com câncer principalmente em tumores do sistema linfático. Estudamos também algumas proteínas com múltiplos domínios conectados por regiões flexíveis e que são: (1) duas chaperonas da classe das HSP40 (proteínas Sis1 e Ydj1) juntamente com construções onde alguns domínios dessas proteínas foram cortados; (2) a proteína ribonucléica heterogênea hnRNP-Q que está envolvida em importantes funções do RNA. Experiências de SAXS foram realizadas, fornecendo parâmetros dimensionais e informações de forma dessas proteínas em solução. Modelos de baixa resolução das possíveis conformações foram calculados a partir das curvas de SAXS usando métodos de modelagem ab initio combinados com modelagem de corpos rígidos. Os resultados forneceram informações importantes para elucidar as funções biológicas dessas proteínas. É importante ressaltar que, para realizar os estudos com proteínas em solução, é necessário contar com uma instrumentação adequada e devidamente montada para a aplicação da técnica de SAXS. Para isso, durante o período de desenvolvimento deste doutorado houve um grande investimento na montagem, teste e caracterização de instrumentos, junto à equipe de profissionais do Laboratório Nacional de Luz Síncrotron (LNLS), completando o comissionamento da estação experimental SAXS2 do LNLS
Abstract: The traditional techniques for structural characterization of macromolecules are based on a compact and structured conformation of the macromolecule. Flexible or disordered regions have usually been regarded as a great hindrance to techniques like X-ray protein crystallography and nuclear magnetic resonance (NMR). The need to study functional activity of natively unfolded proteins and flexible multidomain proteins came to the light rather recently, defying the classical structure¿function paradigm where a protein must have a well-defined 3-D structure to be functional. In this type of situation, the small-angle X-ray scattering (SAXS) technique appears as a unique tool to deal with this problem. Indeed, the application of SAXS methods to the characterization of soft matter (e.g. polymers) and macromolecules in solution has already succeeded during the last years. In this work we decided to face the challenge of characterizing proteins that do not have a well defined structure. The SAXS experimental technique as well as the mathematical methods and calculations needed special attention in order to be correctly applied to study the specific problem of unstructured proteins in solution. Thus, it was possible to find evidence of the structural details of these proteins and obtain a low resolution 3-D average structure. Here we present the study of two proteins that belong to the group of natively unfolded proteins: (1) The FEZ1 protein, which is necessary for axon growth, and (2) the proteins indentified as Ki-1/57, which is found in diverse cancer cells mainly in lymphatic systems tumors. We also studied some flexible multidomain proteins: (1) two chaperones from the groups of HSP40 (the proteínas Sis1 e Ydj1), and two mutant constructions where some domains were deleted; (2) the heterogeneous ribonucleoprotein hnRNP-Q which is related to an array of important functions of RNA. Several SAXS experiments were performed providing overall parameters and important shape information about those proteins in solution. Low resolution models for the possible conformations of these proteins were restored from the SAXS curves using ab initio modeling methods combined with rigid body modeling. The SAXS results provided a unique structural background for the biologists to deal with the function of these proteins. SAXS experiments with proteins in solution demand the use of a specific instrumentation properly developed for those studies. So, it is important to mention that, throughout the duration of this doctorate, specific instrumentation development and testing was done together with the technical staff of the Brazilian Synchrotron Light Laboratory (LNLS, Campinas, SP, Brazil), collaborating with the commissioning of the new SAXS2 workstation, completed in 2008
Doutorado
Física
Doutor em Ciências
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Kothamachu, Varun Bhaskar. "An investigation into dynamic and functional properties of prokaryotic signalling networks." Thesis, University of Exeter, 2016. http://hdl.handle.net/10871/26597.
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In this thesis, I investigate dynamic and computational properties of prokaryotic signalling architectures commonly known as the Two Component Signalling networks and phosphorelays. The aim of this study is to understand the information processing capabilities of different prokaryotic signalling architectures by examining the dynamics they exhibit. I present original investigations into the dynamics of different phosphorelay architectures and identify network architectures that include a commonly found four step phosphorelay architecture with a capacity for tuning its steady state output to implement different signal-response behaviours viz. sigmoidal and hyperbolic response. Biologically, this tuning can be implemented through physiological processes like regulating total protein concentrations (e.g. via transcriptional regulation or feedback), altering reaction rate constants through binding of auxiliary proteins on relay components, or by regulating bi-functional activity in relays which are mediated by bifunctional histidine kinases. This study explores the importance of different biochemical arrangements of signalling networks and their corresponding response dynamics. Following investigations into the significance of various biochemical reactions and topological variants of a four step relay architecture, I explore the effects of having different types of proteins in signalling networks. I show how multi-domain proteins in a phosphorelay architecture with multiple phosphotransfer steps occurring on the same protein can exhibit multistability through a combination of double negative and positive feedback loops. I derive a minimal multistable (core) architecture and show how component sharing amongst networks containing this multistable core can implement computational logic (like AND, OR and ADDER functions) that allows cells to integrate multiple inputs and compute an appropriate response. I examine the genomic distribution of single and multi domain kinases and annotate their partner response regulator proteins across prokaryotic genomes to find the biological significance of dynamics that these networks embed and the processes they regulate in a cell. I extract data from a prokaryotic two component protein database and take a sequence based functional annotation approach to identify the process, function and localisation of different response regulators as signalling partners in these networks. In summary, work presented in this thesis explores the dynamic and computational properties of different prokaryotic signalling networks and uses them to draw an insight into the biological significance of multidomain sensor kinases in living cells. The thesis concludes with a discussion on how this understanding of the dynamic and computational properties of prokaryotic signalling networks can be used to design synthetic circuits involving different proteins comprising two component and phosphorelay architectures.
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Nguyen, Thi Minh-Ha. "Molecular recognition of ubiquitin and Lysine 63 linked diubiquitin by STAM2 : the effect of the linkers length and flexibility." Thesis, Lyon, 2019. https://n2t.net/ark:/47881/m6668chz.
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Les interactions protéine-proteine sont considérées comme un domaine de recherche important puisqu’elles contrôlent la plupart des processus cellulaires. Chez les cellules eucaryotes, les protéines multi-domaines (MDP), constituées d’au moins deux domaines, représentent plus de 70 % des protéines. Au sein d’une MDP, ces domaines peuvent être identiques ou différents et sont reliés par un segment intrinsèquement désordonné de longueur et de flexibilité variable. Ces protéines peuvent alors adopter de multiples conformations dans l’espace et interagir de manière spécifique avec leurs partenaires biologiques. Malgré de nombreux efforts de recherche dans le domaine, certaines questions restent encore non résolues ou nécessitent une étude approfondie. Mon projet de recherche est d’étudier et de définir le rôle des segments intrinsèquement désordonnés de la protéine STAM2 (Signal transducing adapter molecule 2) impliquée dans la machinerie ESCRT (Endosomal Sorting Complexe Required for Transport) , première étape dans le processus de dégradation lysosomale. Plus précisément, l’étude se focalise sur les effets de la flexibilité et la dynamique de ces segments dans le cas du processus de reconnaissance moléculaire entre STAM2 et l’ubiquitine ou di-ubiquitine. Différents mutants ont alors été conçus : soit avec un domaine totalement ou partiellement supprimé, soit avec un raccourcissement ou une suppression complète du segment ou soit avec de multiples mutations dans la séquence peptidique du segment. Ces différents construits ont été analysés en utilisant une combinaison de techniques biophysiques telles que la relaxation de spin par résonance magnétique nucléaire (RMN), la diffusion des rayons X aux petits angles (SAXS) et le dichroïsme circulaire (CD). Il a alors été démontré qu’une altération du segment désordonné peut entraîner un changement de la dynamique de la protéine et/ou un changement conformationnel. La modification de ce segment influe sur le mouvement inter-domaine et modifie l’affinité entre les construits de STAM2 et la di-ubiquitine sans modifier l’intégrité de chaque domaine et de leur site de liaison. En résumé, les segments intrinsèquement désordonnés procurent une certaine plasticité à la protéine ce qui lui permet de s’adapter et de remplir sa fonction biologique. Il est alors possible d’imaginer dans un futur proche que ces segments soient la nouvelle génération de cibles thérapeutiques pouvant réduire ou supprimer certaines interactions nocivesProtein-protein interaction is considered as an important field of research, as it is the key to control variable cell processes and pathways. In eucaryotic cells, multidomain proteins (MDPs), which consist of more than one domain, take up over 70 % of the pool. Those identical or different domains of a MDP are connected to each other by a linker of variable length and flexibility. For long flexible linker, it allows the protein to sample a wide range of conformation and to adjust interaction in a subtle way. Despite numerous efforts of research on the field, some issues remain unanswered or require further investigation. As part of this thesis, my work aims to define the role taken by the intrinsically disordered linker within MDPs. For that purpose, the STAM2 (Signal transducing adapter molecule 2) protein of the ESCRT (Endosomal Sorting Complexes Required for Transport) machinery was chosen to examine the effect of the flexibility and dynamics of the linker regions on the molecular recognition with ubiquitin and Lysine63-linked di-ubiquitin (K63-Ub2). Such efforts were carried out by designing specific mutants altering the linker regions in different ways. The various truncated versions undergo half or complete deletion of a domain or have their linker either shortened, deleted or modified in the amino acid composition. With a combination of the several biophysical methods namely NMR (Nuclear Magnetic Resonance) spin relaxation, SAXS (Small Angle X-ray Scattering) and CD (Circular Dichroism), the study has demonstrated that the alteration in the linker region modifies the flexibility and the dynamics of the protein, one among them possibly introduces slight change in conformation. Furthermore, the modification of the linker has an impact on the inter-domain motion and alter binding affinities between STAM2 constructs and di-ubiquitin without affecting domains integrity or binding sites. In brief, disordered linkers provide plasticity to the protein, which allow adaptability and specificity to molecular recognition process. As a further application, the linkers included in multidomain proteins could also be the next generation of druggable target as their modification may reduce or completely abolish interactions
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Dupé, Valérie. "Conception multidisciplinaire de microsystèmes autonomes." Phd thesis, Bordeaux 1, 2011. http://tel.archives-ouvertes.fr/tel-00858692.
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Toute action naturelle crée de l'énergie perdue qui pourrait être exploitée pour alimenter nos appareils électriques et mobiles. Nos environnements physiques disposent d'un nombre élevé de micro-sources d'énergies ; certes chacune est de faible puissance, mais leur multiplicité pourrait s'avérer significative, notamment dans le cadre du fonctionnement de microsystèmes. C'est le principe précédent qui a conduit nos travaux sur la problématique de la conception de microsystèmes autonomes. Ainsi, pour être innovante, l'ingénierie de microsystèmes doit à la fois s'appuyer sur la culture de l'électronique, de la mécanique mais aussi de l'énergétique. Le processus de conception est fortement pluridisciplinaire et son efficacité réside dans la capacité à mettre en oeuvre des méthodologies et des outils : - de conception collaborative, - de capitalisation des connaissances techniques, - d'ingénierie multi-physique, - d'ingénierie intégrée. Sur le base de ces fondamentaux, nous avons développé un outil d'aide à la conception. La méthodologie sous-jacente permet : 1- l'analyse et la structuration d'un problème de conception d'un microsystème autonome : cette phase conduit l'identification, la description fonctionnelle et environnementale du système et de son environnement. 2- la modélisation des connaissances : une analyse architecturale conduit à la description des composants et des interactions liées au microsystème (directement ou indirectement) puis à la modélisation des comportements, 3- la qualification énergétique et le couplage physique : la réutilisation structurée des modèles de connaissances est pilotée pour coupler les modèles physiques et décrire les sources, les puits et les mécanismes énergétiques des environnements, 4- la conduite de la recherche de concepts innovants : la base de connaissances, les critères de qualification et la description fonctionnelle préalablement construits sont agencés dans une seule méthode de conception virtuelle pour rechercher des concepts de solutions innovants, 5- le pré-dimensionnement : tout en assurant l'intégration des outils spécialisés de simulation (méthode des éléments finis et simulation fonctionnelle), le prédimensionnement de microsystèmes autonomes est supportée selon un schéma synthétique, assurant un raisonnement abductif (ou bottom-up). La conjonction des raisonnements physiques, l'intégration des méthodes et des cultures métiers, l'exploration virtuelle des espaces de solutions et la modélisation constituent les bases d'un nouveau moyen d'aide à la conception de microsystèmes autonomes. Cette approche a été déployée pour la conception d'un capteur piézoélectrique autonome.
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Záleský, Martin. "Nemocnice v Pardubicích - příprava a organizace přístavby pavilonu." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2015. http://www.nusl.cz/ntk/nusl-227281.
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This thesis discusses the preparation and organization of the extension construction of multi-purpose Pavilion in Pardubice hospital. The thesis contains a summary accompanying technical report, technical regulations for CFA piles and contact insulation system. Those 3 regulations have developed inspection and test plans. Next parts od the work are time schedule and an itemized budget of the pavilion, time and financial plan of the whole building, Occupational safety and health instructions, environmental issues during the construction, design of mechanical set, system of construction site project. There is also noise study made during the implementation of the construction of the pavilion. Finally there is also situation of construction, CFA pilot implementation scheme and contract.
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Hammouch, Zohra. "Développement d’une méthode numérique pour les équations de Navier-Stokes en approximation anélastique : application aux instabilités de Rayleigh-Taylor." Thesis, Paris 11, 2012. http://www.theses.fr/2012PA112086/document.
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L’approximation dite « anélastique » permet de filtrer les ondes acoustiques grâce à un développement asymptotique deséquations de Navier-Stokes, réduisant ainsi le pas en temps moyen, lors de la simulation numérique du développement d’instabilités hydrodynamiques. Ainsi, les équations anélastiques sont établies pour un mélange de deux fluides pour l’instabilité de Rayleigh-Taylor. La stabilité linéaire de l’écoulement est étudiée pour la première fois pour des fluides parfaits, par la méthode des modes normaux, dans le cadre de l’approximation anélastique. Le problème de Stokes issu des équations de Navier-Stokes sans les termes non linéaires (une partie de la poussée d’Archiméde est prise en compte) est défini ; l’éllipticité est démontrée, l’étude des modes propres et l’invariance liée à la pression sont détaillés. La méthode d’Uzawa est étendue à l’anélastique en mettant en évidence le découplage des vitesses en 3D, le cas particulier k = 0 et les modes parasites de pression. Le passage au multidomaine a permis d’établir les conditions de raccord (raccord Co de la pression sans condition aux limites physiques). Les algorithmes et l’implantation dans le code AMENOPHIS sont validés par les comparaisons de l’opérateur d’Uzawa développé en Fortran et à l’aide de Mathematica. De plus des résultats numériques ont été comparés à une expérience avec des fluides incompressibles. Finalement, une étude des solutions numériques obtenues avec les options anélastique et compressible a été menée. L’étude de l’influence de la stratification initiale des deux fluides sur le développement de l’instabilité de Rayleigh-Taylor est amorcéeThe « anelastic » approximation allows us to filter the acoustic waves thanks to an asymptotic development of the Navier-Stokes equations, so increasing the averaged time step, during the numerical simulation of hydrodynamic instabilitiesdevelopment. So, the anelastic equations for a two fluid mixture in case of Rayleigh-Taylor instability are established.The linear stability of Rayleigh-Taylor flow is studied, for the first time, for perfect fluids in the anelastic approximation.We define the Stokes problem resulting from Navier-Stokes equations without the non linear terms (a part of the buoyancyis considered) ; the ellipticity is demonstrated, the eigenmodes and the invariance related to the pressure are detailed.The Uzawa’s method is extended to the anelastic approximation and shows the decoupling speeds in 3D, the particular casek = 0 and the spurius modes of pressure. Passing to multidomain allowed to establish the transmission conditions.The algorithms and the implementation in the existing program are validated by comparing the Uzawa’s operator inFortran and Mathematica langages, to an experiment with incompressible fluids and results from anelastic and compressiblenumerical simulations. The study of the influence of the initial stratification of both fluids on the development of the Rayleigh-Taylor instability is initiated
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Grüner, David Salzwedel Horst. "Entwurf eines Kernels für die Multidomain-Simulation /." 2007. http://www.gbv.de/dms/ilmenau/abs/525934995gruen.txt.
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Bakota, Erica Laraine. "Multidomain Peptides: Sequence-Nanostructure Relationships and Biological Applications." Thesis, 2011. http://hdl.handle.net/1911/64380.
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Peptides are materials that, as a result of their polymeric nature, possess enormous
versatility and customizability. Multidomain peptides are a class of peptides that selfassemble
to form stable, cytocompatible hydro gels. They have an ABA block motif, in
which the A block is composed of charged amino acids, such as lysine, and the B block
consists of alternating hydrophilic and hydrophobic amino acids, such as glutamine and
leucine. The B block forms a facial amphiphile that drives self-assembly. The charged A
blocks simultaneously limit self-assembly and improve solubility. Self-assembly is
triggered by charge screening of these charged amino acids, enabling the formation of ~sheet
fibers. The development of an extended nanofiber network can result in the
formation of a hydrogel.
Systematic modifications to both the A and B blocks were investigated, and it was
found that sequence modifications have a large impact on peptide nanostructure and
hydrogel rheology. The first modification examined is the substitution of amino acids
within the hydrophilic positions of the B block. The second set of modifications
investigated was the incorporation of aromatic amino acids in the B block. Finally, the
charged block was varied to generate different net charges on the peptides, a change
which impacted the ability to use these peptides in cell culture.
Two applications of multi domain peptide nanofibers are explored, the first of
which is the delivery of novel therapies in vivo. One multidomain peptide is able to form
hydrogels that undergo shear-thinning and rapid recovery. This gel can be loaded with
cytokines and growth factors that have been secreted by embryonic stem cells, and these
molecules can be subsequently released in a therapeutic setting. Another application for
multidomain peptide is their use as biocompatible surfactants. Single-walled carbon
nanotubes have been widely investigated for their unique optical and electrical properties,
but their solubility in aqueous systems has been a challenge. Multidomain peptides
solubilize carbon nanotubes, are less cytotoxic than detergents such as SDBS, and
preserve the ability of carbon nanotubes to fluoresce. Some of these peptides are also
compatible with cell culture, allowing the delivery of single-walled carbon nanotubes to
cells.
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Spangenberg, Oliver. "Guanylatkinase: Von einem aktiven Enzym zu einem inaktiven Multidomänen-Protein." Doctoral thesis, 2001. http://hdl.handle.net/11858/00-1735-0000-0006-ABDA-1.
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Po-Jui, Chiang. "Development of Multidomain Pseudospectral Mode Solvers for Optical Waveguides and Photonic Crystals." 2007. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-2301200712313600.
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Chiang, Po-Jui, and 江柏叡. "Development of Multidomain Pseudospectral Mode Solvers for Optical Waveguides and Photonic Crystals." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/90246621156748878021.
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博士國立臺灣大學
光電工程學研究所
95
A new full-vectorial pseudospectral mode solver based on multidomain pseudospectral methods for optical waveguides with arbitrary step-index profile is presented. Both Legendre and Chebyshev collocation methods are employed. The multidomain advantage helps in proper fulfillment of dielectric interface conditions, which is essential in achieving high numerical accuracy. Suitable multidomain division of the computational domain is performed to deal with general curved interfaces of the permittivity profile and field continuity conditions are carefully imposed across the dielectric interfaces. Therefore, a curvilinear coordinate mapping technique is introduced to perfectly deal with curved boundaries. Each contiguous subdomain is joined by intensionally imposing different types of boundary conditions to enhance the accuracy. Moreover, perfectly matched layer (PML) absorbing boundary conditions are incorporated into the model so that leaky modes with complex propagation constants can be analyzed. The solver is applied to the calculation of guided modes on optical fibers, fused fiber couplers, D-shaped fibers, channel waveguides, rib waveguides, and photonic crystal fibers, and comparison with analytical results or reported ones based on other methods is made. It is demonstrated that numerical accuracy in the effective index up to the remarkable 1010 order can be easily achieved. The multidomain pseudospectral scheme is for the first time applied to the calculation of the band diagrams of two-dimensional photonic crystals with the inclusion of the required periodic boundary conditions, and is again shown to possess excellent numerical convergence behavior and accuracy. The proposed method shows uniformly excellent convergence characteristics for both the transverse-electric and transverse-magnetic waves in the analysis of di_erent structures. The analysis of a mini band gap with the normalized frequency gap width as small as on the order of 107 is also shown to demonstrate the extremely high accuracy of the proposed method. A novel numerical calculation of chromatic dispersion coefficients of optical fibers including holy fibers is also proposed in this research using a procedure involving Chebyshev-Lagrange interpolation polynomials. Only numerically determined effective indices at several wavelengths are needed for obtaining the dispersion curve and no direct numerical differentiation of the effective refractive index is involved.
46
Huang, Chia-Chien, and 黃家健. "A Full-Vectorial Multidomain Spectral Collocation Method for Modal Analysis of Optical Waveguides." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/23362687003555126385.
Full textAbstract:
博士國立臺灣大學
應用力學研究所
91
Abstract An accurate and efficient solution method using full-vertorial multidomain spectral collocation method is proposed for computing optical waveguides with discontinuous refractive index profiles. The method is formulated in terms of the transverse magnetic fields. The use of domain decomposition divides the usual single domain into a few subdomains at the interfaces of discontinuous refractive index profiles. Each subdomain can be expanded by a suitable set of orthogonal basis functions and patched at these interfaces by matching the physical boundary conditions. In addition, a new technique which incorporating the effective index method and the Wentzel-Kramers-Brillouin method for the a priori determination of the scaling factor in Hermite-Gauss or Laguerre-Gauss basis functions is introduced to considerably save the computational time without experimenting with it. The present method shares the same desirable property of spectral collocation method that can provide fast and accurate solution but avoids the oscillatory solutions and improves the poor convergence problem of simple spectral collocation method with single domain where regions of discontinuous refractive index profiles exist. Computations of several 2-D and 3-D waveguide structures, such as three-layer, planar diffused, metal-clad, planar directional coupler, diffused channel, rectangular dielectric, and semiconductor rib waveguides have been carried out to test the accuracy and efficiency of the present method. Detailed comparisons of the present results with exact solutions or previously published data based on other methods are included and all the results are found to be in excellent agreement.
47
Zenner, Gerhardt [Verfasser]. "Cellular effects of the multidomain serine, threonine kinase from Yersinia enterocolitica / von Gerhardt Zenner." 2007. http://d-nb.info/984614478/34.
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Nai-Yuan, Shih. "The Multidomain Pseudospectral Frequency-domain Method and Its Application in Modeling of Photonic Structures." 2007. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-3001200714352900.
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Spangenberg, Oliver [Verfasser]. "Guanylatkinase : von einem aktiven Enzym zu einem inaktiven Multidomänen-Protein / vorgelegt von Oliver Spangenberg." 2001. http://d-nb.info/962816183/34.
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Shih, Nai-Yuan, and 施乃元. "The Multidomain Pseudospectral Frequency-domain Method and Its Application in Modeling of Photonic Structures." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/26999795467161209071.
Full textAbstract:
碩士國立臺灣大學
光電工程學研究所
95
Conventional frequency-domain algorithms suffer more or less from convergence and efficiency problems; to overcome these headaches, an alternative called the multidomain pseudospectral frequency-domain method is presented in this thesis. The superior "spectral accuracy" greatly reduces the requirement for discretization density for smooth functions, and the multidomain approach patches distinct materials together properly. Via implementation of some practical examples, the utility and potential of the method for modeling and design of photonic structures are verified.