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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Adenovirus Chromatin: The Dynamic Nucleoprotein Complex Throughout Infection

Giberson, Andrea N. 23 August 2013 (has links)
Adenovirus (Ad) is a widely studied DNA virus, but the nucleoprotein structure of the viral genome in the cell is poorly characterized. Our objective is to study Ad DNA-protein associations and how these affect the viral life cycle. Most of the viral DNA condensing protein, protein VII, is lost within a few hours of infection and this loss is independent of transcription. Cellular histones associate with the viral DNA after removal of protein VII, with a preferential deposition of H3.3. Micrococcal nuclease accessibility assays at 6 hpi showed laddering of the viral DNA, suggesting the genome is wrapped in physiologically spaced nucleosomes. Although viral DNA continues to associate with H3.3 at late times of infection, the overall level of association with histones is greatly reduced. Knockdown of the H3.3 chaperone HIRA had no effect on the viral life cycle suggesting that other H3.3 chaperones are involved. Our studies have begun to elucidate the nucleoprotein structure of Ad DNA in the infected cell nucleus.
122

Algorithmic techniques for the acoustical analysis of exhaust systems

Dowling, John F. January 2005 (has links)
One dimensional, linear, plane-wave modelling of silencer systems in the frequency domain provides an efficient means to analyse their acoustic performance. Software packages are available to analyse silencers within these modelling parameters; however, they are heavily restricted. The thesis develops an algorithm that increases the computational efficiency of the silencer analysis. The thesis concentrates on how data, within a software package, is stored, retrieved and analysed. The computational efficiency is increased as a result of the predictable patterns caused by the repetitive nature of exhaust system analysis. The work uses the knowledge gained from the construction of two previous algorithms of similar parameters; it isolates and maximises their advantages whilst minimising their associated disadvantages. The new algorithm is dependent on identifying consecutively sequenced exhaust components and sub-systems of such components within the whole exhaust system. The algorithm is further generalised to include multiple time-variant sources, multiple radiation points and exhaust systems that have a balance pipe. Another feature of the improved algorithm encompasses the option of modelling secondary noise sources such as might arise from flow generated noise or be included for active noise cancellation systems. The validation of these algorithmic techniques is demonstrated by comparison of the theoretical noise predictions with experimental or known results. These predictions are achieved by writing computational code using object orientated programming techniques in the language of c++ to implement the algorithms.
123

Resultados de existência de soluções para problemas elípticos assintoticamente lineares / On results about existence of solutions to asymptotic linear elliptic problems

Gonzaga, Anderson dos Santos [UNESP] 21 February 2017 (has links)
Submitted by Anderson dos Santos Gonzaga null (andersongonzaga25@yahoo.com.br) on 2018-01-16T17:28:55Z No. of bitstreams: 1 Gonzaga.dissertação.pdf: 1264952 bytes, checksum: e682e5fd46c5a7d68506f3f9499cded5 (MD5) / Approved for entry into archive by Claudia Adriana Spindola null (claudia@fct.unesp.br) on 2018-01-16T17:58:17Z (GMT) No. of bitstreams: 1 gonzaga_as_me_prud.pdf: 1264952 bytes, checksum: e682e5fd46c5a7d68506f3f9499cded5 (MD5) / Made available in DSpace on 2018-01-16T17:58:17Z (GMT). No. of bitstreams: 1 gonzaga_as_me_prud.pdf: 1264952 bytes, checksum: e682e5fd46c5a7d68506f3f9499cded5 (MD5) Previous issue date: 2017-02-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Nesse trabalho teórico na área das equações diferenciais parciais elípticas, estudamos uma versão estacionária da equação de Schrödinger não-linear, com não-linearidade do tipo assintoticamente linear. O objetivo principal versa sobre obter resultados de existência de uma solução nodal radialmente simétrica. Ainda, sob algumas condições, buscamos também obter informações sobre o seu índice de Morse. / In this theoretical work in elliptic partial di erential equations, we study a stationary version for the nonlinear Schödinger equation with nonlinearity of the assymptotically linear type. The main objective is getting, some results of existence for a radially symmetric nodal solution. Moreover, under some conditions, we look also obtaining information about its Morse index.
124

Discovery and characterisation of the novel, pathological GNB3 mutation (D153del/Gβ3D), in the retinopathy globe enlarged (rge) chicken

Tummala, Hemanth January 2008 (has links)
The common human GNB3 825C > T variant, which is present in 50% of the world’s chromosomes, has previously been shown to predispose individuals to hypertension, cardiac and neural disorders. This variant causes the production of a stable and gain of function protein Gβ<sub>3S</sub>- This thesis describes the discovery of a novel D153del mutation that produces an unstable, loss of function, protein Gβ<sub>3D </sub> in the recessively inherited, retinopathy globe enlarged (rge) chickens. This thesis also demonstrates that the normal Gβ<sub>3</sub> downstream phosphorylation signalling pathways are significantly altered in a tissue specific manner in rge chicken organs and in a human GNB3 825TT lymphoblast cell line. In rge tissues expressing Gβ<sub>3D</sub> protein, the cAMP induced GRK2 phosphorylation activity is significantly altered. Moreover MAPK1 (ERK2) phosphorylation is significantly decreased compared to normal tissues. In contrast human 825TT cell lines expressing the Gβ<sub>3S</sub> protein, showed enhanced cAMP induced GRK2 and MAPK (ERK1 and ERK2) phosphorylation activity. These results confirm previous findings of 825C > T Gβ<sub>3</sub> studies, that Gβ<sub>3S</sub> is indeed a hyper-activating structural variant, in contrast to the D153del Gp3D is a classical recessively inherited non-functional mutation.
125

Computational principles for an autonomous active vision system

Sherbakov, Lena Oleg 22 January 2016 (has links)
Vision research has uncovered computational principles that generalize across species and brain area. However, these biological mechanisms are not frequently implemented in computer vision algorithms. In this thesis, models suitable for application in computer vision were developed to address the benefits of two biologically-inspired computational principles: multi-scale sampling and active, space-variant, vision. The first model investigated the role of multi-scale sampling in motion integration. It is known that receptive fields of different spatial and temporal scales exist in the visual cortex; however, models addressing how this basic principle is exploited by species are sparse and do not adequately explain the data. The developed model showed that the solution to a classical problem in motion integration, the aperture problem, can be reframed as an emergent property of multi-scale sampling facilitated by fast, parallel, bi-directional connections at different spatial resolutions. Humans and most other mammals actively move their eyes to sample a scene (active vision); moreover, the resolution of detail in this sampling process is not uniform across spatial locations (space-variant). It is known that these eye-movements are not simply guided by image saliency, but are also influenced by factors such as spatial attention, scene layout, and task-relevance. However, it is seldom questioned how previous eye movements shape how one learns and recognizes an object in a continuously-learning system. To explore this question, a model (CogEye) was developed that integrates active, space-variant sampling with eye-movement selection (the where visual stream), and object recognition (the what visual stream). The model hypothesizes that a signal from the recognition system helps the where stream select fixation locations that best disambiguate object identity between competing alternatives. The third study used eye-tracking coupled with an object disambiguation psychophysics experiment to validate the second model, CogEye. While humans outperformed the model in recognition accuracy, when the model used information from the recognition pathway to help select future fixations, it was more similar to human eye movement patterns than when the model relied on image saliency alone. Taken together these results show that computational principles in the mammalian visual system can be used to improve computer vision models.
126

Statistical parametric speech synthesis using conversational data and phenomena

Dall, Rasmus January 2017 (has links)
Statistical parametric text-to-speech synthesis currently relies on predefined and highly controlled prompts read in a “neutral” voice. This thesis presents work on utilising recordings of free conversation for the purpose of filled pause synthesis and as an inspiration for improved general modelling of speech for text-to-speech synthesis purposes. A corpus of both standard prompts and free conversation is presented and the potential usefulness of conversational speech as the basis for text-to-speech voices is validated. Additionally, through psycholinguistic experimentation it is shown that filled pauses can have potential subconscious benefits to the listener but that current text-to-speech voices cannot replicate these effects. A method for pronunciation variant forced alignment is presented in order to obtain a more accurate automatic speech segmentation something which is particularly bad for spontaneously produced speech. This pronunciation variant alignment is utilised not only to create a more accurate underlying acoustic model, but also as the driving force behind creating more natural pronunciation prediction at synthesis time. While this improves both the standard and spontaneous voices the naturalness of spontaneous speech based voices still lags behind the quality of voices based on standard read prompts. Thus, the synthesis of filled pauses is investigated in relation to specific phonetic modelling of filled pauses and through techniques for the mixing of standard prompts with spontaneous utterances in order to retain the higher quality of standard speech based voices while still utilising the spontaneous speech for filled pause modelling. A method for predicting where to insert filled pauses in the speech stream is also developed and presented, relying on an analysis of human filled pause usage and a mix of language modelling methods. The method achieves an insertion accuracy in close agreement with human usage. The various approaches are evaluated and their improvements documented throughout the thesis, however, at the end the resulting filled pause quality is assessed through a repetition of the psycholinguistic experiments and an evaluation of the compilation of all developed methods.
127

Etude structurale et fonctionnelle de la variante d'histone H2AZ / Structural and functional study of the histone variant H2AZ

Obri, Arnaud 20 September 2012 (has links)
La variante d’histone H2AZ joue un rôle important dans l’activation de la transcription, la prolifération cellulaire, le développement et la différentiation. H2AZ orne les promoteurs de la majorité des gènes, mais les mécanismes de bases de cette localisation sont inconnus. La compréhension de l’assemblage et du désassemblage du nucléosome passe par la caractérisation de la dynamique du nucléosome et des chaperonnes d’histones. L’objectif de ma thèse était d’identifier des chaperonnes spécifiques impliqués dans la dynamique de H2AZ en utilisant une approche de protéomique. Pour élucider les mécanismes de déposition/éviction de H2AZ, j’ai purifié le complexe prénucléosomale de H2AZ et j’ai caractérisé toutes les protéines associées. J’ai trouvé que Anp32e fait partie du complexe p400/TIP60 qui est présumée pour être responsable de l’échange d’H2AZ sur la chromatine. Anp32e présente une spécificité pour le dimère H2AZ-H2B, car il n’interagit pas avec le dimère H2A-H2B. L’interaction est accomplie au niveau d’une petite région dans le domaine d’ancrage sur H2AZ et au niveau d’un nouveau domaine ZID sur Anp32e. Finalement, j’ai montré que la suppression d’Anp32e entraine : un défaut dans la dé-répression des gènes dont l’expression est contrôlée par une hormone et une accumulation sur les promoteurs de ces derniers. Dans l’ensemble ces résultats identifient Anp32e comme une nouvelle chaperonne de la variante d’histoneH2AZ impliquée dans l’éviction de H2AZ chez les mammifères. / The histone variant H2AZ has emerged as a key regulator of chromatin function and plays an essential role in transcriptional activation, cell proliferation, development, and differentiation. H2AZ marks nucleosomes flanking the promoters of most genes, but the mechanistic basis for this localization is unknown. A mechanistic understanding of nucleosome assembly/disassembly requiresa detailed knowledge of nucleosome thermodynamics and histone chaperones. The aim of my thesis was to identify specific chaperone involved in H2AZ dynamic by using biochemical and proteomic strategies. To elucidate the mechanism of H2AZ deposition/eviction, I purified the prenucelosomal H2AZ complex and characterized in details the interacting protein partners. I found that Anp32e is a member of the presumed H2A.Z histone-exchange complex p400/TIP60. Bacterially expressed Anp32e binds only to the H2AZ/H2B dimers but not to the H2A/H2B. Anp32e interacts with a short region of the docking domain of H2A.Z. The binding occurred through a novel Anp32e motif, termed ZID. Finally, I show that down regulation of Anp32e interferes with both the de-repression of hormone dependent genes and H2A.Z removal from their promoter. Our data identified Anp32e as a novel mammalian H2AZ chaperone invoved in H2AZ eviction.
128

Rozhodování v malých a středních podnicích / Decision making in SMEs

Celba, Šimon January 2016 (has links)
The goal of the work is the creation of a system for decision making support in the company BSL, s.r.o.. The system for the decision making is to resolve the problem with decision making in choosing personal computers for the companys partners. In the thesis a system for decision making for the company BSL is suggested, as well as its functions and the methodology it utilizes are clearly described. The abilities of the systems are introduced through realistic computations during the choice of a personal computer for individual BSL partners. The results are interpreted through a user interface where the individual options of interaction and users system functions are described. The conclusion of the work includes the results of the individual computations along with suggestion of the best personal computer for individual partners.
129

Hodnocení podnikatelských účtů / Ratings business accounts

ŠUSTROVÁ, Lucie January 2016 (has links)
The diploma thesis is focused on using methods of multiple criteria decision making, in this case about business accounts. In theoretical part is described the banking systém of Czech republic, then methods of multiple criteria evaluation.The basic aim of this work was to evaluate the order of business accounts in terms of advantageousness, which are offered by banks on the banking market in the Czech republic. The sectional aim of this work is to get known with the problems of optimal choice of business accounts for a certain group of consumers, which in this case are small businesses. Before choosing a new business account it is always necessary to carefully explore banking market and its offers of business accounts. The important part of this thesis is that the certain client has to consider his preferences before we use quantitative methods. In this diploma thesis has also done a survey about the evaluation of business accounts. Then there are compared results of using methods of multiple criteria evaluation of the survey and model client. In conclusion, the results are described in the order of banking products from the best to the worst business account.
130

Vícekriteriální analýza variant při výběru zaměstnance / Multiple-criteria Analysis in a Choice of an Employer

Růžek, Martin January 2017 (has links)
This thesis deals with the issue of decision-making process in recruitment and selection of employees using methods of multi-criteria analysis options. The theoretical part of the thesis is focused on explaining the concepts of human resources and HR management. This area describes in detail the activities of selection process. Another area defines the basics of project management and project manager job. The third part deals with the theory of multi-criteria decision and the last area describes the process models. The practical part of the thesis uses the knowledge gained in the theoretical part for the real application to selection process. First, the company selected is introduced, especially its history, organizational structure and the current selection process. Then the current selection process is analysed and the results of analysis initiate the creation of a new process. For achieving the higher quality of results are included and applied methods of multi-criteria analysis of options and the questionnaire method in the new process. In conclusion, the achieved results are discussed with the manager and the current selection process is compared with a new selection process.

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