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Vaníček, Jakub. "Měření relativní variance optické intenzity." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2011. http://www.nusl.cz/ntk/nusl-219091.
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The intention of this master‘s thesis is the measurment of relative variance of optical intensity. In the first place, I have been studied Kolmogorov cascade theory of turbulence and relative variance of optical intensity . In addition, I have been deal with turbulent cells, Gaussian beam, Top Hat beam and influence of the atmospheric turbulences on the intensity profile of the laser beam. Lastly I have been measured determine influence of the atmospheric turbulences on the intensity profile of the laser beam and I have been calculated relative variance of optical intensity. I have suggested the optimum beam profile in the turbulent atmosphere from acquired data.
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Zhang, Yue. "Detection copy number variants profile by multiple constrained optimization." HKBU Institutional Repository, 2017. https://repository.hkbu.edu.hk/etd_oa/439.
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Copy number variation, causing by the genome rearrangement, generally refers to the copy numbers increased or decreased of large genome segments whose lengths are more than 1kb. Such copy number variations mainly appeared as the sub-microscopic level of deletion and duplication. Copy number variation is an important component of genome structural variation, and is one of pathogenic factors of human diseases. Next generation sequencing technology is a popular CNV detection method and it has been widely used in various fields of life science research. It possesses the advantages of high throughput and low cost. By tailoring NGS technology, it is plausible to sequence individual cells. Such single cell sequencing can reveal the gene expression status and genomic variation profile of a single-cell. Single cell sequencing is promising in the study of tumor, developmental biology, neuroscience and other fields. However, there are two challenging problems encountered in CNV detection for NGS data. The first one is that since single-cell sequencing requires a special genome amplification step to accumulate enough samples, a large number of bias is introduced, making the calling of copy number variants rather challenging. The performances of many popular copy number calling methods, designed for bulk sequencings, are not consistent and cannot be applied on single-cell sequenced data directly. The second one is to simultaneously analyze genome data for multiple samples, thus achieving assembling and subgrouping similar cells accurately and efficiently. The high level of noises in single-cell-sequencing data negatively affects the reliability of sequence reads and leads to inaccurate patterns of variations. To handle the problem of reliably finding CNVs in NGS data, in this thesis, we firstly establish a workflow for analyzing NGS and single-cell sequencing data. The CNVs identification is formulated as a quadratic optimization problem with both constraints of sparsity and smoothness. Tailored from alternating direction minimization (ADM) framework, an efficient numerical solution is designed accordingly. The proposed model was tested extensively to demonstrate its superior performances. It is shown that the proposed approach can successfully reconstruct CNVs especially somatic copy number alteration patterns from raw data. By comparing with existing counterparts, it achieved superior or comparable performances in detection of the CNVs. To tackle this issue of recovering the hidden blocks within multiple single-cell DNA-sequencing samples, we present an permutation based model to rearrange the samples such that similar ones are positioned adjacently. The permutation is guided by the total variational (TV) norm of the recovered copy number profiles, and is continued until the TV-norm is minimized when similar samples are stacked together to reveal block patterns. Accordingly, an efficient numerical scheme for finding this permutation is designed, tailored from the alternating direction method of multipliers. Application of this method to both simulated and real data demonstrates its ability to recover the hidden structures of single-cell DNA sequences.
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Abrhám, Ondřej. "Odhad měsíčních odchylek závodových nákladů dle nákladových skupin - analýza postupu a návrh zlepšení." Master's thesis, Vysoká škola ekonomická v Praze, 2008. http://www.nusl.cz/ntk/nusl-5252.
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Theory: - Controlling - its function and structure - Costs Analytical part: - Cost variance tracking and evaluation of its monthly prediction - Proposal of best practices for cost variance prediction done on monthly basis
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Oliveira, Madalena Mendes de Almeida Esteves de. "On Robo assessment of risk profiles." Master's thesis, Instituto Superior de Economia e Gestão, 2020. http://hdl.handle.net/10400.5/20778.
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Mestrado em FinançasNos tempos que correm, o mundo tecnológico tem crescido a um ritmo muito acelerado, o que significa que tem de haver uma rápida adaptação, e as empresas sentem a necessidade de se reinventar. As inovações tecnológicas também alcançaram a indústria de serviços de gestão de ativos com os chamados Robo-Advisors. Estas são as plataformas que fornecem aconselhamento financeiro ou gestão automatizada de investimentos. Os Robo-Advisors coletam informações sobre a situação financeira e os objetivos futuros de seus clientes através de questionários, recomendando carteiras baseadas em ETFs, supostamente adequadas ao perfil de risco do investidor. No entanto, os questionários parecem vagos e os robôs não revelam os métodos usados na alocação de ativos. Este estudo visa contribuir para a compreensão da eficácia dessas plataformas. Baseia-se na teoria da utilidade esperada e, para vários níveis de aversão relativa ao risco, propomos carteiras de média-variância ótimas. Em seguida, comparamos as nossas carteiras com as carteiras propostas pela plataforma Riskalyze, para três tipos diferentes de investidores: conservador, moderado e agressivo. Avaliando o seu desempenho in-sample e out-of-sample. Concluímos que, a longo prazo, a metodologia utilizada pelos robo-portfolios, de acordo com o perfil de risco do investidor, pode ser eficaz para investidores que apresentam um maior nível de aversão ao risco, porém para investidores com aversão ao risco relativamente menor os portfólios de média-variância tendem a ter melhor desempenho.
Nowadays, the technological world has been growing at a very fast rate, which means there has to be a quick adaptation and companies feel the need to reinvent themselves. Technological innovations also reached the asset management service industry with the so-called the Robo-Advisors. These are platforms that provide financial advice or automated investment management. Robo-Advisors collect information about their clients' financial situation and future goals through questionnaires, then recommending ETF based portfolios supposed to fit investor's risk profile. However, questionnaires seem to be vague, and robos do not reveal the methods used in asset allocation. This study aims at contributing to the understanding the effectiveness of these platforms. It relies on expected utility theory, and, for various levels of relative risk aversion we propose optimal mean-variance portfolios. We then compare our portfolios with the portfolios proposed by the Riskalyze platform, for three different types of investors: conservative, moderate and aggressive. By evaluating their in-sample and out-of-sample performance. We conclude, that in the long run, the methodology used by robo-portfolios, according to the investor's risk profile, can be effective for investors who have a higher level of risk aversion, however for investors with relatively lower risk aversion the mean-variance portfolios tend to perform better.
info:eu-repo/semantics/publishedVersion
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Wilson, Benton Wade. "Modeling of performance behavior in gas condensate reservoirs using a variable mobility concept." Texas A&M University, 2003. http://hdl.handle.net/1969.1/317.
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The proposed work provides a concept for predicting well performance behavior in a gas condensate reservoir using an empirical model for gas mobility. The proposed model predicts the behavior of the gas permeability (or mobility) function in the reservoir as condensate evolves and the gas permeability is reduced in the near-well region due to the "condensate bank". The proposed model is based on observations of simulated reservoir performance and predicts the behavior of the gas permeability over time and radial distance. This model is given by:
The proposed concept has potential applications in the development of a pressure-time-radius solution for gas condensate reservoirs experiencing this type of mobility behavior. We recognize that the proposed concept (i.e., a radially-varying gas permeability) is oversimplified, in particular, it ignores the diffusive effects of the condensate (i.e., the viscosity-compressibility behavior). However, we have effectively validated the proposed model using literature results derived from numerical simulation.
This new solution is presented graphically in the form of "type curves." We propose that the "time" form of this solution be used for applications in well test analysis. Previous developments used for the analysis of well test data from gas condensate reservoirs consider the radial composite reservoir model, which utilizes a "step change" in permeability at some radial distance away from the wellbore. Using our proposed solution we can visualize the effect of the varying gas permeability in time and radius (a suite of (dimensionless) radius and time format plots are provided). In short, we can visualize the evolution of the condensate zone as it evolves in time and radial distance.
A limitation is the simplified form of the kg profile as a function of radius and time - as well as the dependence/appropriateness of the α-parameter. While we suspect that the α-parameter represents the influence of both fluid and rock properties, we do not examine how such properties can be used to calculate the α-parameter.
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Dabo, Issa-Mbenard. "Applications de la théorie des matrices aléatoires en grandes dimensions et des probabilités libres en apprentissage statistique par réseaux de neurones." Electronic Thesis or Diss., Bordeaux, 2025. http://www.theses.fr/2025BORD0021.
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Le fonctionnement des algorithmes d’apprentissage automatique repose grandement sur la structure des données qu’ils doivent utiliser. La majorité des travaux de recherche en apprentissage automatique se concentre sur l’étude de données homogènes, souvent modélisées par des variables aléatoires indépendantes et identiquement distribuées. Pourtant, les données apparaissant en pratique sont souvent hétérogènes. Nous proposons dans cette thèse de considérer des données hétérogènes en les dotant d’un profil de variance. Cette notion, issue de la théorie des matrices aléatoires, nous permet notamment d’étudier des données issues de modèles de mélanges. Nous nous intéressons plus particulièrement à la problématique de la régression ridge à travers deux modèles : la régression ridge linéaire (linear ridge model) et la régression ridge à caractéristiques aléatoires (random feature ridge model). Nous étudions dans cette thèse la performance de ces deux modèles dans le cadre de la grande dimension, c’est-à-dire lorsque la taille de l’échantillon d’entraînement et la dimension des données tendent vers l’infini avec des vitesses comparables. Dans cet objectif, nous proposons des équivalents asymptotiques de l’erreur d’entraînement et de l’erreur de test relatives aux modèles d’intérêt. L’obtention de ces équivalents repose grandement sur l’étude spectrale issue de la théorie des matrices aléatoires, des probabilités libres et de la théorie des trafics. En effet, la mesure de la performance de nombreux modèles d’apprentissage dépend de la distribution des valeurs propres de matrices aléatoires. De plus, ces résultats nous ont permis d’observer des phénomènes spécifiques à la grande dimension, comme le phénomène de la double descente. Notre étude théorique s’accompagne d’expériences numériques illustrant la précision des équivalents asymptotiques que nous fournissonsThe functioning of machine learning algorithms relies heavily on the structure of the data they are given to study. Most research work in machine learning focuses on the study of homogeneous data, often modeled by independent and identically distributed random variables. However, data encountered in practice are often heterogeneous. In this thesis, we propose to consider heterogeneous data by endowing them with a variance profile. This notion, derived from random matrix theory, allows us in particular to study data arising from mixture models. We are particularly interested in the problem of ridge regression through two models: the linear ridge model and the random feature ridge model. In this thesis, we study the performance of these two models in the high-dimensional regime, i.e., when the size of the training sample and the dimension of the data tend to infinity at comparable rates. To this end, we propose asymptotic equivalents for the training error and the test error associated with the models of interest. The derivation of these equivalents relies heavily on spectral analysis from random matrix theory, free probability theory, and traffic theory. Indeed, the performance measurement of many learning models depends on the distribution of the eigenvalues of random matrices. Moreover, these results enabled us to observe phenomena specific to the high-dimensional regime, such as the double descent phenomenon. Our theoretical study is accompanied by numerical experiments illustrating the accuracy of the asymptotic equivalents we provide
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Hillwig, Todd C. "Analysis of the radial profile emissivity of accretion disks in cataclysmic variables." Virtual Press, 1995. http://liblink.bsu.edu/uhtbin/catkey/941346.
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HAUDOT, STEPHANE. "Contribution a l'etude des caracteristiques aerodynamiques d'un profil a polaire variable." Aix-Marseille 2, 1995. http://www.theses.fr/1995AIX22067.
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Dans le cadre d'une approche numerique, cette etude presente les caracteristiques aerodynamiques et geometriques d'un profil d'aile susceptible de se deformer en fonction du champ de vitesse infinie amont ; l'objectif final etant d'induire des variations significatives de portance et de trainee. La configuration retenue est constituee d'un profil naca traverse par un canal horizontal (deux elements). L'etude est realisee a partir du code de calcul en mecanique des fluides phoenics (methode des volumes finis et schema hybrid) et dans le cadre d'un ecoulement turbulent (modele k-e). Plusieurs types de deplacements sont consideres: une reduction ou une augmentation de la section du canal et une rotation de l'un des elements. Les resultats obtenus revelent que seul un mouvement de rotation conduit a des variations significatives de portance et de trainee: dans l'intervalle considere, une reduction de dix pourcents est obtenue pour le cx et le cz. Une etude experimentale devant etre realisee ulterieurement, une simulation numerique de l'ensemble veine d'essais profil complet a egalement ete realisee ; l'objectif etait d'optimiser la geometrie de l'ensemble veine d'essais profil complet afin de conserver qualitativement les performances aerodynamiques du profil en milieu non-confine
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Lee, Joongsup. "New control charts for monitoring univariate autocorrelated processes and high-dimensional profiles." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/42711.
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In this thesis, we first investigate the use of automated variance estimators in distribution-free statistical process control (SPC) charts for univariate autocorrelated processes. We introduce two variance estimators---the standardized time series overlapping area estimator and the so-called quick-and-dirty autoregressive estimator---that can be obtained from a training data set and used effectively with distribution-free SPC charts when those charts are applied to processes exhibiting nonnormal responses or correlation between successive responses. In particular, we incorporate the two estimators into DFTC-VE, a new
distribution-free tabular CUSUM chart developed for autocorrelated processes; and we compare its performance with other state-of-the-art distribution-free SPC charts. Using either of the two variance estimators, the DFTC-VE outperforms its competitors in terms of both in-control and
out-of-control average run lengths when all the competing procedures are tested on the same set of independently sampled realizations of selected
autocorrelated processes with normal or nonnormal noise components.
Next, we develop WDFTC, a wavelet-based distribution-free CUSUM chart for detecting shifts in the mean of a high-dimensional profile with noisy components that may exhibit nonnormality, variance heterogeneity, or correlation between profile components. A profile describes the relationship between a selected quality characteristic and an input (design) variable over the experimental region. Exploiting a discrete wavelet transform (DWT) of the mean in-control profile, WDFTC selects a reduced-dimension vector of the associated DWT components from which the mean in-control profile can be
approximated with minimal weighted relative reconstruction error. Based on randomly sampled Phase I (in-control) profiles, the covariance matrix of the corresponding reduced-dimension DWT vectors is estimated using a matrix-regularization method; then the DWT vectors are aggregated (batched) so that the nonoverlapping batch means of the reduced-dimension DWT vectors
have manageable covariances. To monitor shifts in the mean profile during Phase II operation, WDFTC computes a Hotelling's T-square--type statistic from successive nonoverlapping batch means and applies a CUSUM procedure to those statistics, where the associated control limits are evaluated
analytically from the Phase I data. We compare WDFTC with other state-of-the-art profile-monitoring charts using both normal and nonnormal
noise components having homogeneous or heterogenous variances as well as independent or correlated components; and we show that WDFTC performs well, especially for local shifts of small to medium size, in terms of both in-control and out-of-control average run lengths.
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Encarnação, Rui Jorge Junqueiro. "Análise do perfil de ácidos gordos de camarinha, Palaemonetes varians." Master's thesis, ISA, 2013. http://hdl.handle.net/10400.5/6122.
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Mestrado em Engenharia Zootécnica - Produção Animal - Instituto Superior de Agronomia / Faculdade de Medicina VeterináriaOne of the benefits associated with the consumption of fishery products is their fatty acid composition. In this dissertation we analyze the fatty acids profile of Atlantic ditch shrimp Palaemonetes varians, determined by gas chromatography. For this, 16 samples were collected in the Sado estuary area and examined. This study identified the majority of the P. varians fatty acids. In terms of highest quantity, we had the palmitic acid in SFA group, the oleic acid in MUFA and finally EPA in PUFA. Higher n-3/n-6 and PUFA/SFA ratios were also noticed. Related outcomes were found in studies associated to several other species of crustaceans. In July, the P. varians exhibited lower levels of MUFA, higher SFA values and higher n-3/n-6 ratio in comparison with the values registered in November (p<0,001). Comparing adult and juvenile P. varians, and despite not having significant variations in PUFA, it is noted the higher concentration of MUFA and lower SFA in adults (p<0,05). Few significant differences were observed between wild and not wild P. varians. A higher concentration of palmitic acid was found in not wild P. varians.These differences may be explained mainly by the food ingested by P. varians.
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Johnson, Emma Grace. "Exploring profiles of social behaviour in dementia syndromes: Identifying targets for intervention." Thesis, The University of Sydney, 2022. https://hdl.handle.net/2123/29675.
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The behavioural variant of frontotemporal dementia (bvFTD) is characterised by social impairments that impact social behaviour. This thesis examines how apathy and disinhibition, core features of bvFTD, manifest as behaviour within the social environment, and discusses the implications of these symptoms on the capacity for social behaviour. Chapter 1 describes the background of bvFTD and associated disorders, and the social symptoms of bvFTD. This is followed by a short review of apathy in bvFTD in Chapter 2. Chapter 3 examines the utility of a novel task to assess social disinhibition in bvFTD. Results demonstrated that while people with bvFTD display increased social disinhibition, the provision of guidelines about social expectation facilitate more appropriate social behaviour. Chapter 4 explores whether aspects of prosocial motivation are retained in bvFTD to modify behaviour in social settings to foster their own social reputation. The results indicate that people with bvFTD appear to adjust behaviour when they are conscious that their social choices are being observed. This may indicate that prosocial motivation to engage in reputation management is retained in people with bvFTD, to some extent. The findings have implications for developing interventions to facilitate prosocial behaviour in patients. In Chapter 5, the thesis turns to examine the role of oxytocin in dementia syndromes. The findings of this study indicate that plasma oxytocin levels are not reduced in dementia, which has implications for the measurement of oxytocin in future clinical trials. Collectively, the results of this thesis reveal the importance of considering behavioural symptoms as they are manifested in social context. From a clinical perspective, these findings have important implications for the management of social impairment in bvFTD.
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Lee, Joshua D. "Multiple sclerosis in Asian populations : the genetic and environmental determinants of variable susceptibility and clinical profile." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/49974.
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Multiple sclerosis is a chronic, inflammatory disorder of the central nervous system, thought to primarily affect persons of Caucasian ancestry. Despite growing recognition of multiple sclerosis and clinical variants such as neuromyelitis optica in persons of other ethnicities, relevant research in emerging populations is comparatively scant. Consequently, current understanding with respect to clinical outcomes and risk factors in this ethnic group is remarkably under-developed. The overarching objective of this dissertation was to address these knowledge gaps using a multi-disciplinary approach focusing on Asian-ethnic populations in Canada and China.
The prevalence of multiple sclerosis in an Asian-ethnic population of Canada was found to be intermediate to that typically reported in Asia and in the general Canadian population. Longitudinal analysis also revealed an increase in incidence among females of Asian ancestry in Canada. In comparative analysis in a Canadian clinic population, long-term clinical outcomes of multiple sclerosis in patients of Asian ancestry were remarkably similar to those in non-Asian patients. Male sex and later age at onset were associated with less favourable clinical outcomes, irrespective of ethnicity or region. In immigrant and Canadian-born patients, duration of exposure to the Canadian environment prior to onset was associated with multiple sclerosis, whereas exposure to the regional environment of Asia was associated with neuromyelitis optica. Case-control analysis revealed a robust association of smoking with multiple sclerosis risk and clinical outcomes in Canadians of Asian ancestry. Genetic studies confirmed the overall low rate of familial recurrence in this ethnic group, but also identified novel variants associated with risk and clinical phenotypes.
The findings underscore the importance of ethnicity-related genetic and environmental factors in modifying susceptibility to and clinical presentation of multiple sclerosis and related disorders in persons of Asian ancestry. Nevertheless, these results also suggest that the clinical trajectory in patients of Asian ancestry may be more comparable to classic clinical descriptions than previously believed. Taken together, the findings presented in this dissertation contribute new perspectives to the epidemiology and etiology of multiple sclerosis and related disorders, and advance knowledge in an emerging patient population in Canada and globally.Medicine, Faculty of
Medical Genetics, Department of
Graduate
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Bribiesca, argomedo Fédérico. "Contrôle et stabilité Entrée-Etat en dimension infinie du profil du facteur de sécurité dans un plasma Tokamak Infinite dimensional control and Input-to-State stability of the safety factor profile in a Tokamak plasma." Phd thesis, Université de Grenoble, 2012. http://tel.archives-ouvertes.fr/tel-00920942.
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Dans cette thèse, on s'intéresse au contrôle du profil de facteur de sécurité dans un plasma tokamak. Cette variable physique est liée à plusieurs phénomènes dans le plasma, en particulier des instabilités magnétohydrodynamiques (MHD). Un profil de facteur de sécurité adéquat est particulièrement important pour avoir des modes d'opération avancés dans le tokamak, avec haut confinement et stabilité MHD. Pour cela faire, on se focalise sur la commande du gradient du profil de flux magnétique poloidal dans le tokamak. L'évolution de cette variable est donnée par une équation de diffusion avec des coefficients distribuées et temps-variants. En utilisant des techniques de type Lyapunov et les propriétés de stabilité entrée-état du système on propose une loi de commande robuste qui prend en compte des contraintes non-linéaires dans l'action imposées par la physique des actionneurs.
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DeBusk-Lane, Morgan. "Variable- and Person-Centered Approaches to Examining Construct-Relevant Multidimensionality in Writing Self-Efficacy." VCU Scholars Compass, 2019. https://scholarscompass.vcu.edu/etd/5938.
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Writing self-efficacy is a vital component to a students’ motivation and will to succeed towards writing. The measurement of writing self-efficacy over the past 40 years, despite its development, continues to largely be represented by Confirmatory Factor Analysis models that are limited due to their restricted item to factor constraints. These constraints, given prior literature and the theoretical understanding of self-efficacy, do not adequately model construct- relevant psychometric multidimensionality as a product of conceptual overlap or a hierarchical or general factor. Given this, the present study’s purpose was to examine the adapted Self-efficacy for Writing Scale (SEWS) for the presence of construct-relevant psychometric multidimensionality through a series of measurement model comparisons and person-centered approaches. Using a sample 1,466 8th, 9th, and 10th graders, a bifactor exploratory structural equation model was found to best represent the data and demonstrate that the SEWS exhibits both construct-relevant multidimensionality as a function of conceptual overlap and the presence of a hierarchical theme. Using factor scores derived from this model, latent profile analysis was conducted to further establish validity of the measurement model and examine how students disaggregate into groups based on their response trends of the SEWS. Three profiles emerged greatly differentiated by global writing self-efficacy, with obvious and substantively varying specific factor differences between profiles. Concurrent, divergent, and discriminant validity evidence was established through a series of analyses that assessed predictors and outcomes of the profiles (e.g. demographics, standardized writing assessments, grades). Theoretical and educator implications and avenues for future researcher were discussed.
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Zucknick, Manuela. "Multivariate analysis of tumour gene expression profiles applying regularisation and Bayesian variable selection techniques." Thesis, Imperial College London, 2008. http://hdl.handle.net/10044/1/4397.
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High-throughput microarray technology is here to stay, e.g. in oncology for tumour classification and gene expression profiling to predict cancer pathology and clinical outcome. The global objective of this thesis is to investigate multivariate methods that are suitable for this task. After introducing the problem and the biological background, an overview of multivariate regularisation methods is given in Chapter 3 and the binary classification problem is outlined (Chapter 4). The focus of applications presented in Chapters 5 to 7 is on sparse binary classifiers that are both parsimonious and interpretable. Particular emphasis is on sparse penalised likelihood and Bayesian variable selection models, all in the context of logistic regression. The thesis concludes with a final discussion chapter. The variable selection problem is particularly challenging here, since the number of variables is much larger than the sample size, which results in an ill-conditioned problem with many equally good solutions. Thus, one open problem is the stability of gene expression profiles. In a resampling study, various characteristics including stability are compared between a variety of classifiers applied to five gene expression data sets and validated on two independent data sets. Bayesian variable selection provides an alternative to resampling for estimating the uncertainty in the selection of genes. MCMC methods are used for model space exploration, but because of the high dimensionality standard algorithms are computationally expensive and/or result in poor Markov chain mixing. A novel MCMC algorithm is presented that uses the dependence structure between input variables for finding blocks of variables to be updated together. This drastically improves mixing while keeping the computational burden acceptable. Several algorithms are compared in a simulation study. In an ovarian cancer application in Chapter 7, the best-performing MCMC algorithms are combined with parallel tempering and compared with an alternative method.
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Hollar, Carol M. "Estimation of Selected Milk Protein Genetic Variants by Multi-Component Analysis of Amino Acid Profiles." DigitalCommons@USU, 1992. https://digitalcommons.usu.edu/etd/5390.
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Cation-exchange fast protein liquid chromatography separated whole casein into β-casein A2, A1, and B, K-casein, αs1-casein, and αs2-casein fractions as well as γ-caseins and several unidentified peaks using a urea-acetate buffer at pH 5 and a NaCl gradient. The whole casein fractions eluted in the following order: breakdown products of β-casein and unidentified peaks; β-casein A2, Al, and B; additional breakdown products of β-casein and unidentified peaks; K-casein; αs1-casein; and αs2-casein. The calculated composition of the four major caseins correlated well with values obtained using anion-exchange fast protein liquid chromatography at pH 7. An acid-PAGE gel confirmed that the three β-casein peaks were variants of β-casein.
Incubating herd bulk whole casein with neuraminidase (EC 3.2.1.18) removed carbohydrate from K-casein. Anion-exchange fast protein liquid chromatography separated whole casein into β-casein breakdown products, K-casein A and B, β-casein, αs2-casein, and αs1-casein peaks as well as three unidentified fractions using bis-Tris-propane-urea buffer at pH 7 and a NaCl gradient. Fractions of whole casein eluted in the following order: breakdown products of β-casein and unidentified fractions A and B; K-casein fraction; unidentified C fraction; β-casein; αs2-casein; and αs1-casein. Following treatment with neuraminidase, K-casein eluted as K-casein B and A rather than a series of peaks. Casein samples from individual cows containing known combinations of K-casein A and B confirmed that the peaks were K-casein variants.
Isoelectric focusing on a PhastSystem™ separated K-casein A and B; β-casein A1, A2, A3, and B; αs1-casein Band C; β-lactoglobulin A and B; αs2-casein A; and α-lactalbumin B. Minimal preparation and a short separation time enabled many whole milk and whole casein samples to be phenotyped daily.
Stepwise regression equations derived to predict samples as homozygous or heterozygous for K-casein A and B and β-casein A1, A2, and B had coefficient of determination values of .18, .58, .82, and .72 for K-casein A and B, β-casein A1, β-casein A2, and β-casein B. Although amino acid analysis can identify whether β-casein A1, A2, or B variants are present, it cannot identify whether K-casein A and B variants are present.
Percentages of K-casein, β-casein, αs1-casein, and αs2-casein obtained with isoelectric focusing, cation-exchange fast protein liquid chromatography, and anion-exchange fast protein liquid chromatography compare well with published results. Isoelectric focusing and anion-exchange fast protein liquid chromatography methods separated K-casein into its A and B variants. Isoelectric focusing and cation-exchange fast protein liquid chromatography separated β-casein into its A1, A2, and B variants. Individual cows homozygous for K-casein A or B expressed the same amount of K-casein. When results from individual cows heterozygous for K-casein are combined, the two alleles are expressed equally; on an individual cow basis, however, some cows expressed more K-casein B than K-casein A. Individual cows homozygous for β-casein A1, A2 or B expressed the same amount of β-casein. When the results for individual cows heterozygous for β-casein are combined, the two β-casein alleles are expressed equally. In milk from individual cows typed β-casein A2B, slightly more B than A2 was expressed with cation-exchange fast protein liquid chromatography.
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Kim, Keunpyo. "Process Monitoring with Multivariate Data:Varying Sample Sizes and Linear Profiles." Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/29741.
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Multivariate control charts are used to monitor a process when more than one quality variable associated with the process is being observed. The multivariate exponentially weighted moving average (MEWMA) control chart is one of the most commonly recommended tools for multivariate process monitoring. The standard practice, when using the MEWMA control chart, is to take samples of fixed size at regular sampling intervals for each variable. In the first part of this dissertation, MEWMA control charts based on sequential sampling schemes with two possible stages are investigated. When sequential sampling with two possible stages is used, observations at a sampling point are taken in two groups, and the number of groups actually taken is a random variable that depends on the data. The basic idea is that sampling starts with a small initial group of observations, and no additional sampling is done at this point if there is no indication of a problem with the process. But if there is some indication of a problem with the process then an additional group of observations is taken at this sampling point. The performance of the sequential sampling (SS) MEWMA control chart is compared to the performance of standard control charts. It is shown that that the SS MEWMA chart is substantially more efficient in detecting changes in the process mean vector than standard control charts that do not use sequential sampling. Also the situation is considered where different variables may have different measurement costs. MEWMA control charts with unequal sample sizes based on differing measurement costs are investigated in order to improve the performance of process monitoring. Sequential sampling plans are applied to MEWMA control charts with unequal sample sizes and compared to the standard MEWMA control charts with a fixed sample size. The steady-state average time to signal (SSATS) is computed using simulation and compared for some selected sets of sample sizes. When different variables have significantly different measurement costs, using unequal sample sizes can be more cost effective than using the same fixed sample size for each variable.
In the second part of this dissertation, control chart methods are proposed for process monitoring when the quality of a process or product is characterized by a linear function. In the historical analysis of Phase I data, methods including the use of a bivariate T² chart to check for stability of the regression coefficients in conjunction with a univariate Shewhart chart to check for stability of the variation about the regression line are recommended. The use of three univariate control charts in Phase II is recommended. These three charts are used to monitor the Y-intercept, the slope, and the variance of the deviations about the regression line, respectively. A simulation study shows that this type of Phase II method can detect sustained shifts in the parameters better than competing methods in terms of average run length (ARL) performance. The monitoring of linear profiles is also related to the control charting of regression-adjusted variables and other methods.Ph. D.
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BEN, ZINEB TARAK. "Analyse des zones a forts gradients de contraintes dans les plaques composites elancees a profil variable." Paris, ENSAM, 1996. http://www.theses.fr/1996ENAM0004.
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Il s'agit d'etudier l'influence d'une variation rapide de l'epaisseur d'une plaque composite verre-epoxy soumise a un chargement de flexion pure. Le profil de la zone a epaisseur variable est defini par deux parametres geometriques que nous faisons evoluer pour etudier leur influence. Un modele numerique par elements finis a deux echelles a ete developpe. La premiere est macroscopique et concerne la majeure partie a epaisseur constante. Elle permet de calculer le comportement global de l'eprouvette. La deuxieme est mesoscopique et represente les domaines a epaisseur variable. Elle permet le calcul de l'etat local de concentration de contraintes. Une loi de transition est introduite au niveau des frontieres entre les deux zones a echelle de modelisation differente. Pour valider ce modele et etudier les types de rupture, une campagne experimentale a ete menee. Elle a consiste a caracteriser le composite et a solliciter en flexion pure des eprouvettes composites presentant la forme adoptee lors de la modelisation. Elles sont fabriquees par le procede rtm. La sollicitation de flexion pure est assuree grace a un banc d'essais entierement concu au sein du laboratoire et adapte aux structures flexibles. Une bonne correlation entre les resultats numeriques et experimentaux a ete observee
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Tergny, Guillaume. "Allocation dynamique de portefeuille avec profil de gain asymétrique : risk management, incitations financières et benchmarking." Phd thesis, Conservatoire national des arts et metiers - CNAM, 2011. http://tel.archives-ouvertes.fr/tel-00629049.
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Les gérants de portefeuille pour compte de tiers sont souvent jugés par leur performance relative à celle d'un portefeuille benchmark. A ce titre, ils sont amenés très fréquemment à utiliser des modèles internes de "risk management" pour contrôler le risque de sous-performer le benchmark. Par ailleurs, ils sont de plus en plus nombreux à adopter une politique de rémunération incitative, en percevant une commission de sur-performance par rapport au benchmark. En effet, cette composante variable de leur rémunération leur permet d'augmenter leur revenu en cas de sur-performance sans contrepartie en cas de sous-performance. Or de telles pratiques ont fait récemment l'objet de nombreuses polémiques : la période récente de crise financière mondiale a fait apparaître certaines carences de plusieurs acteurs financiers en terme de contrôle de risque ainsi que des niveaux de prise de risque et de rémunération jugés excessifs. Cependant, l'étude des implications de ces pratiques reste un thème encore relativement peu exploré dans le cadre de la théorie classique des choix dynamiques de portefeuille en temps continu. Cette thèse analyse, dans ce cadre théorique, les implications de ces pratiques de "benchmarking" sur le comportement d'investissement de l'asset manager. La première partie étudie les propriétés de la stratégie dynamique optimale pour l'asset manager concerné par l'écart entre la rentabilité de son portefeuille et celle d'un benchmark fixe ou stochastique (sur ou sous-performance). Nous considérons plusieurs types d'asset managers, caractérisés par différentes fonctions d'utilité et qui sont soumis à différentes contraintes de risque de sous-performance. Nous montrons en particulier quel est le lien entre les problèmes d'investissement avec prise en compte de l'aversion à la sous-performance et avec contrainte explicite de "risk management". Dans la seconde partie, on s'intéresse à l'asset manager bénéficiant d'une rémunération incitative (frais de gestion variables, bonus de sur-performance ou commission sur encours additionnelle). On étudie, selon la forme de ses incitations financières et son degré d'aversion à la sous-performance, comment sa stratégie d'investissement s'écarte de celle de l'investisseur (ou celle de l'asset manager sans rémunération incitative). Nous montrons que le changement de comportement de l'asset manager peut se traduire soit par une réduction du risque pris par rapport à la stratégie sans incitation financière soit au contraire par une augmentation de celui-ci. Finalement, nous montrons en quoi la présence de contraintes de risque de sous-performance, imposées au gérant ou traduisant son aversion à la sous-performance, peut être bénéfique à l'investisseur donnant mandat de gestion financière.
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Little, Jonathon. "Multilevel and longitudinal factor structure of the life skills profile-16 : an application of multilevel covariance structure analysis and its variants." Phd thesis, Canberra, ACT : The Australian National University, 2015. http://hdl.handle.net/1885/151122.
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Hindalong, Emily Ann. "A study of methods for learning phylogenies of cancer cell populations from binary single nucleotide variant profiles." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/54550.
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An accurate phylogeny of a cancer tumour has the potential to shed light on numerous phenomena, such as key oncogenetic events, relationships between clones, and evolutionary responses to treatment. Most work in cancer phylogenetics to-date relies on bulk tissue data, which can resolve only a few genotypes unambiguously. Meanwhile, single-cell technologies have considerably improved our ability to resolve intra-tumour heterogeneity. Furthermore, most cancer phylogenetic methods use classical approaches, such as Neighbor-Joining, which put all extant species on the leaves of the phylogenetic tree. But in cancer, ancestral genotypes may be present in extant populations. There is a need for scalable methods that can capture this phenomenon.
We have made progress on this front by developing the Genotype Tree representation of cancer phylogenies, implementing three methods for reconstructing Genotype Trees from binary single-nucleotide variant profiles, and evaluating these methods under a variety of conditions. Additionally, we have developed a tool that simulates the evolution of cancer cell populations, allowing us to systematically vary evolutionary conditions and observe the effects on tree properties and reconstruction accuracy.
Of the methods we tested, Recursive Grouping and Chow-Liu Grouping appear to be well-suited to the task of learning phylogenies over hundreds to thousands of cancer genotypes. Of the two, Recursive Grouping has the strongest and most stable overall performance, while Chow-Liu Grouping has a superior asymptotic runtime that is competitive with Neighbor-Joining.Science, Faculty of
Graduate
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MONTALBANO, Maria. "Determination of protein content and fatty acid profile in milk of Girgentana goat breed for evaluation of nutritional characteristics of dairy products." Doctoral thesis, Università degli Studi di Palermo, 2014. http://hdl.handle.net/10447/90853.
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I geni delle caseine caprine mostrano un elevato polimorfismo, che influenza non solo la quantità di caseine nel latte ma anche le caratteristiche strutturali e nutrizionali e le proprietà tecnologiche del latte. Uno degli obiettivi di questa tesi è stato quello di separare e quantificare le più comuni varianti alleliche caseiniche nel latte di capra di razza Girgentana, una razza autoctona siciliana, e di valutare l’effetto dei polimorfismi caseinici sul contenuto di caseina nel latte.
I genotipi e, quindi, gli alleli ai diversi geni delle caseine sono stati rilevati utilizzando protocolli di PCR, PCR-RFLP, AS-PCR e analisi di sequenziamento. I campioni di latte sono stati preparati seguendo il metodo proposto da Bobé et al. (1998) e analizzati mediante metodo RP- HPLC. È stata utilizzata una colonna analitica in fase inversa C8 (Zorbax 300SB - C8 RP, 3.5μm, 300A, 150 × 4.6 ID ) e la rilevazione è stata effettuata ad una lunghezza d'onda di 214 nm. La procedura è stata sviluppata utilizzando campioni di latte individuale crudo di capre di razza Girgentana. Per gli esperimenti di calibrazione, le varianti genetiche pure sono state estratte da campioni di latte individuale di animali con genotipo noto, in quanto commercialmente non erano disponibili le varianti alleliche estratte da latte caprino. In particolare, sono stati utilizzati animali con genotipo alla alphas1-caseina AA, BB, FF e NN, genotipo alla beta-caseina CC e C'C', genotipo alla alphas2-caseina AA e FF, e genotipo alla kappa-caseina AA e BB. La validazione del metodo prevedeva il test di linearità e le stima di ripetibilità, riproducibilità e precisione. Una relazione lineare è stata osservata tra le concentrazioni delle proteine e le aree sottese dal picco nell’intervallo di concentrazione in analisi, con l’ottenimento di limiti di rilevabilità bassi. La ripetibilità e riproducibilità sono risultate soddisfacenti sia per i tempi di ritenzione e che per le aree sottese ai picchi.
Un altro obiettivo di questa tesi è stato quello di studiare le interazioni tra nutrizione e genotipo al locus dell’s1-caseina (CSN1S1) caprina, valutando l’impatto delle diete a base di foraggio fresco e di un supplemento energetico sui profili di caseina e di acidi grassi (FA) nel latte di capra di razza Girgentana. Dodici capre sono state selezionate aventi lo stesso genotipo ai loci di s2-caseina, β-caseina e κ-caseina, e differente genotipo alla CSN1S1: omozigote per alleli forti (AA) o eterozigoti per alleli forti e deboli (AF). Le capre di ciascun genotipo sono state divise in tre gruppi e alimentate ad libitum con tre diete, secondo un disegno di quadrato Latino 3×3: foraggio fresco, Sulla, (SFF), SFF più 800 g/d di orzo (SFB), fieno misto più 800 g /d di orzo (MHB).Goat casein genes showed high polymorphism, which influences not only the quantity of caseins in milk but also the structural and nutritional characteristics and technological properties of milk. One of the aims of this thesis was to separate and quantify the most common allelic variants of caseins in milk of Girgentana goat breed, a Sicilian autochthonous breed, and to evaluate the effect of casein polymorphisms on casein content. The genotypes and, therefore, the alleles at different casein genes were detected using PCR, PCR-RFLP, AS-PCR protocols and sequencing analysis. Milk samples were prepared following the method proposed by Bobe et al. (1998) and analyzed by RP-HPLC method. A reversed-phase analytical column C8 (Zorbax 300SB-C8 RP, 3.5µm, 300Å, 150×4.6 I.D.) was used and the detection was made at wavelength of 214 nm. The procedure was developed using individual raw milk samples of Girgentana goat breed. For calibration experiments, pure genetic variants were extracted from individual milk samples of animals with known genotypes, considering that commercial standards for goat allelic variants were not available. In particular, were used animals with AA, BB, FF and NN genotypes at alphas1-casein; CC and C'C' genotypes at beta-casein; AA and FF genotypes at alphas2-casein; and AA and BB genotypes at kappa-casein. Method validation consisted in testing linearity, repeatability, reproducibility and accuracy. A linear relationship between the concentrations of proteins and peak areas was observed over the concentration range, with low detection limits. Repeatability and reproducibility were satisfactory for both retention times and peak areas. Another aim of this thesis was to investigate the interactions between nutrition and the genotype at s1-casein locus (CSN1S1) in goats, evaluating the impact of fresh forage-based diets and an energy supplement on the casein and fatty acid (FA) profiles of milk from Girgentana goat breed. Twelve goats were selected for having the same genotype at the s2-casein, β-casein, and κ-casein loci and differing in the CSN1S1 genotype: homozygous for strong alleles (AA) or heterozygous for strong and weak alleles (AF). Goats of each genotype were divided into three groups and, according to a 3×3 Latin square design, fed ad libitum with three diets: Sulla fresh forage (SFF), SFF plus 800 g/d of barley (SFB), mixed hay plus 800 g/d of barley (MHB).
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Masada, Teruhisa. "Structural performance of profile-wall plastic pipes under relatively shallow soil cover and subjected to large surface load." Ohio : Ohio University, 1996. http://www.ohiolink.edu/etd/view.cgi?ohiou1174611925.
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COFFINIER, CATHERINE. "Etude du profil d'expression et de l'inactivation du gene vhnf1 (variant hepatocyte nuclear factor 1) chez la souris." Paris 11, 1999. http://www.theses.fr/1999PA112104.
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Vhnf1 est un facteur de transcription a homeodomaine exprime dans les reins, le foie et le pancreas. Nous avons inactive ce gene chez la souris en remplacant son premier exon par le gene lacz. La detection de l'activite -galactosidase placee sous controle du promoteur de vhnf1 nous a permis de decrire finement le profil d'expression de ce gene, chez l'adulte et au cours du developpement. Nous avons ainsi montre l'expression particuliere de ce gene dans des structures epitheliales tubulaires telles que les canaux biliaires et pancreatiques et les tubules renaux. La mutation vhnf1, letale a l'etat homozygote au jour 7,5 post-coitum, conduit a un retard de croissance et a la desorganisation des tissus. Or a ce stade, l'expression de vhnf1 est limitee au domaine extra-embryonnaire de l'endoderme visceral. Afin d'etudier l'effet possible de la mutation vhnf1 dans ce tissu, nous avons analyse la differenciation des cellules es vhnf1-/- et montre que la formation de l'endoderme visceral est alors bloquee. Nous avons ainsi identifie des genes cibles potentiels de vhnf1, egalement affectes in vivo. De plus, nous avons montre que l'endoderme visceral sauvage permet la survie du tissu embryonnaire mutant jusqu'au jour 9,5. L'ensemble de nos resultats montrent le role essentiel de vhnf1 pour la differenciation de l'endoderme visceral. L'analyse d'embryons chimeres contenant des cellules mutantes revele que vhnf1 est requis egalement au cours de la morphogenese de l'embryon. Pour rechercher des fonctions plus tardives de vhnf1, nous avons produit un allele conditionnel en utilisant le systeme cre/loxp. Cet allele, equivalent a un allele sauvage, est delete en presence de la recombinase cre. Les souris conditionnelles croisees avec une lignee exprimant la cre controlee par le promoteur de l'albumine permettent ainsi l'inactivation de vhnf1 dans le tissu hepatique. Les mutants presentent un retard de croissance et un ictere severe, suggerant un role de vhnf1 dans le foie.
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Villazon-Gonzales, Claudia. "Influência de variantes do receptor de LDL e da HMGCoA redutase na resposta à atorvastatina." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/9/9136/tde-10062009-152818/.
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A influencia dos polimorfismos genéticos de HMGCoA redutase (HMGCR) e LDL receptor (LDLR) na resposta a atorvastatina (10 mg/dia/4semanas) foi avaliada em individuos hipercolesterolemicos (HC). Amostras de sangue foram coletadas de 153 HC e 182 normolipidemicos (NL) para determinações de lipideos séricos e extração de DNA. Polimorfismos de troca única (SNP) HMGCR (A11898T e T24558G) e LDLR (C16730T, C20001T, G26857A) foram detectados. por PCR-RFLP. Os alelos HMGCR 11898T e 24558G foram associados com menores triglicérides e VLDL-C séricos nos grupos NL e HC (p<0,05). Além disso, o SNP HM0CR T24558G foi relacionado com HDL-C e apoAI séricos aumentados em resposta a atorvastatina no grupo HC. O alelo LDLR 20001 C foi associado com maior apoAI sérica basal no grupo NL (p=O,034) e com melhor resposta de apoAI a atorvastatina no grupo HC (p=O,045). Foi observada relação entre o haplótipo heterozigoto LDLR 20001 C/16730T e redução significativa de apoB e aumento de apoAI no soro após o tratamento com atorvastatina (p
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Cahill, Paul. "Latest variable mixture modelling : an examination of the influences and profiles of treated drug misuse in the Republic of Ireland." Thesis, University of Ulster, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.421741.
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Ghauri, Farzan Naseer. "Hybrid Photonic Signal Processing." Doctoral diss., University of Central Florida, 2007. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3233.
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This thesis proposes research of novel hybrid photonic signal processing systems in the areas of optical communications, test and measurement, RF signal processing and extreme environment optical sensors. It will be shown that use of innovative hybrid techniques allows design of photonic signal processing systems with superior performance parameters and enhanced capabilities. These applications can be divided into domains of analog-digital hybrid signal processing applications and free-space--fiber-coupled hybrid optical sensors. The analog-digital hybrid signal processing applications include a high-performance analog-digital hybrid MEMS variable optical attenuator that can simultaneously provide high dynamic range as well as high resolution attenuation controls; an analog-digital hybrid MEMS beam profiler that allows high-power watt-level laser beam profiling and also provides both submicron-level high resolution and wide area profiling coverage; and all optical transversal RF filters that operate on the principle of broadband optical spectral control using MEMS and/or Acousto-Optic tunable Filters (AOTF) devices which can provide continuous, digital or hybrid signal time delay and weight selection. The hybrid optical sensors presented in the thesis are extreme environment pressure sensors and dual temperature-pressure sensors. The sensors employ hybrid free-space and fiber-coupled techniques for remotely monitoring a system under simultaneous extremely high temperatures and pressures.Ph.D.
Optics and Photonics
Optics and Photonics
Optics PhD
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Bavay, Cécile. "Adaptation des méthodologies d’évaluation sensorielle aux produits agroalimentaires à forte variabilité." Angers, 2013. https://theses.hal.science/tel-00846841.
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Les caractéristiques sensorielles peuvent être mesurées par des méthodes descriptives d'évaluation sensorielle, parmi lesquelles le profil conventionnel. Les résultats sensoriels de profil présentent une forte variabilité, due, d'une part aux différences entre les sujets du panel, et d'autre part à la variabilité intra-lot, et notamment aux différences existant entre les individus d'un échantillon. À ce jour, la variabilité des sujets est prise en compte et les méthodologies de collecte et d'analyse des données ont été adaptées dans ce but. Néanmoins, la variabilité intra-lot n'a pas été abordée, malgré le challenge qu'elle représente. Avec pour produit modèle la pomme, ce travail de thèse aborde la problématique de la variabilité intra-lot sous deux angles : la mesure de la variabilité et la réduction de la variabilité, dans le but d'obtenir une mesure sensorielle plus fiable. Premièrement, la capacité de discrimination du panel a été observée entre les variétés étudiées et entre les fruits de chaque variété, identifiés comme différents selon une mesure instrumentale. Deuxièmement, afin de prendre en compte la variabilité intra-lot, le modèle d'analyse de la variance classiquement utilisé en évaluation sensorielle a été adapté avec l'ajout d'un facteur fruit hiérarchisé au facteur variété. Cette adaptation implique le partage de chaque fruit par plusieurs sujets. L'application de ce modèle a démontré l'importance de la variabilité intra-lot et l'importance du choix du modèle pour obtenir des résultats plus pertinents. De plus, le modèle d'analyse de la variance déterminé a été adapté afin de distinguer désaccord pur entre les sujets et différences de dispersion. Enfin, une réduction de la variabilité effective est obtenue par le partage des fruits ou par une homogénéisation instrumentale, cette dernière étant dépendante de la variété et de la mesure choisie. Les résultats de ce travail apportent des clés méthodologiques pour l'obtention de résultats fiables dans la cadre de l'évaluation sensorielle de produits variablesThe sensory characteristics are evaluated by descriptive methods of sensory evaluation, such as the conventional profile. The sensory results from profiling present a large variability, due to differences between assessors on the one hand, and within-batch variability, that is differences between units of a sample, on the other hand. To date, differences between assessors are taken into account and sensory methodologies have been adapted for that. Nevertheless, within-batch variability has not been tackled, despite the challenge it represents. With the apple as a model, this PhD work addresses the issue of within-batch variability from two points of view: the measuring of variability and the reduction of variability, with the aim of improving the reliability of the sensory measure. First, the capacity of the panel to discriminate between apples from different cultivars and between apples, identified as different by an instrumental measure, within each cultivar has been observed. Second, in order to take within-batch variability into account, the standard models for analysis of variance used in sensory evaluation has been adapted by adding a fruit factor nested within the cultivar factor. This adaptation requires the sharing of each piece of fruit by several assessors. The application of this model has demonstrated the importance of within-batch variability and the consequence of model choice to obtain more relevant results. In addition, the determined model for analysis of variance has been adapted to distinguish between assessors' disagreement and scaling differences. Finally, a reduction of variability has been obtained through the sharing of fruits and after the homogenization by instrumental measurement, the latter depending on the cultivar and on the chosen measure. The results of the present work provide methodological keys to obtain reliable sensory results in the frame of the evaluation of products subject to biological variation
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Valenti, Giovanna. "La variante G -308 A TNF-alfa quale fattore di rischio per l'obesità e modificatore d¡ effetto del profilo lipidico e dei marker infiammatori." Doctoral thesis, Università di Catania, 2012. http://hdl.handle.net/10761/1063.
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Geni all'interno dell'aplotipo ancestrale 8.1 modificano la risposta immunitaria e influenzano molteplici malattie immunopatologiche. In particolare, il gene del TNFalfa, localizzato in questo aplotipo, potrebbe giocare un ruolo nell'influenzare le caratteristiche del 8.1 AH, ciò determinare forza, efficacia e durata delle reazioni infiammatorie locali e sistemiche. Il TNF-alfa è una citochina pro-infiammatoria pleiotropica, codificata dal gene fattore di necrosi tumorale alfa (TNF-alfa) situato sul cromosoma 6, è in grado di svolgere numerose funzioni di regolazione sulle risposte immunitarie. Nel promotore del gene TNF alfa sono stati identificati diversi SNP, uno di questi è il polimorfismo G-308A. Studi hanno dimostrato che la presenza dell' allele A influisce sulla regolazione dell' espressione del gene, infatti è associata ad una maggiore produzione della molecola stessa. Il TNF-alfa è implicato nello sviluppo dell' obesità: un eccessivo accumulo di grassi nel tessuto adiposo aumentano le concentrazioni ematiche di marker pro-infiammatori quali il TNF-alfa e la proteina C-reattiva, invece, una perdita del peso comporta una diminuzione di tali molecole. Scopo del nostro studio è stato quello di indagare in una popolazione di donne catanesi il ruolo della variante G -308 A TNF-alfa nell' obesità e di studiarne la sua relazione con il profilo lipidico, marker infiammatori e la dieta.
I nostri risultati suggeriscono che la mutazione G-308A del gene del TNF-alfa svolge un ruolo importante nell' obesità poichè le donne con genotipo mutato AA o eterozigote AG erano con più frequenza in sovrappeso o obese rispetto alle donne wild-type. Inoltre, le donne obese AA o AG avevano un rischio 2.9 volte maggiore rispetto alle donne obese wild type. La popolazione in sovrappeso o obesa presentava un' alterazione del profilo lipidico in particolare quella con genotipo AA o AG. inoltre, l' allele A sembrerebbe assumere un ruolo di aumento del rischio di malattie croniche, mentre il genotipo wild-type un significato protettivo. I nostri risultati confermano quanto già osservato in altri studi: lo stato nutrizionale modula significativamente il profilo lipidico e la proteina C-reattiva. Per quanto riguarda l' interazione gene-dieta, i risultati non mostrano un' interazione tra il genotipo TNF-alfa -308 G>A e l'assunzione di acidi grassi. Il ruolo dei grassi assunti con la dieta nell'eziologia dell'obesità è stato affrontato in diversi studi ma rimane controverso. I risultati del nostro studio contribuiscono a chiarire il ruolo della dieta, del profilo lipidico e di alcuni marker infiammatori nello sviluppo dell' obesità, anche considerando il ruolo del genotipo nel modulare la risposta ai cambiamenti dei grassi assunti con la dieta.
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Mok, Ka Wai. "Proline-rich membrane anchor (PRiMA) of acetylcholinesterase (AChE) : characterization of its splicing variants and their expression profiles in different chicken tissues /." View abstract or full-text, 2009. http://library.ust.hk/cgi/db/thesis.pl?BIOL%202009%20MOK.
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Veganzones, David. "Corporate failure prediction models : contributions from a novel explanatory variable and imbalanced datasets approach." Thesis, Lille, 2018. http://www.theses.fr/2018LIL1A004.
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Cette thèse explore de nouvelles approches pour développer des modèles de prédiction de la faillite. Elle contient alors trois nouveaux domaines d'intervention. La première est une nouvelle variable explicative basée sur la gestion des résultats. À cette fin, nous utilisons deux mesures (accruals et activités réelles) qui évaluent la manipulation potentielle des bénéfices. Nous avons mis en évidence que les modèles qui incluent cette nouvelle variable en combinaison avec des informations financières sont plus précis que ceux qui dépendent uniquement de données financières. La seconde analyse la capacité des modèles de faillite d'entreprise dans des ensembles de données déséquilibrés. Nous avons mis en relation les différents degrés de déséquilibre, la perte de performance et la capacité de récupération de performance, qui n'ont jamais été étudiés dans les modèles de prédiction de la faillite. Le troisième unifie les domaines précédents en évaluant la capacité de notre modèle de gestion des résultats proposé dans des ensembles de données déséquilibrés. Les recherches abordées dans cette thèse fournissent des contributions uniques et pertinentes à la littérature sur les finances d'entreprise, en particulier dans le domaine de la prédiction de la failliteThis dissertation explores novel approaches to develop corporate failure prediction models. This thesis then contains three new areas for intervention. The first is a novel explanatory variable based on earnings management. For this purpose, we use two measures (accruals and real activities) that assess potential earnings manipulation. We evidenced that models which include this novel variable in combination with financial information are more accurate than those relying only on financial data. The second analyzes the capacity of corporate failure models in imbalanced datasets. We put into relation the different degrees of imbalance, the loss on performance and the performance recovery capacity, which have never been studied in corporate failure. The third unifies the previous areas by evaluating the capacity of our proposed earnings management model in imbalanced datasets. Researches covered in this thesis provide unique and relevant contributions to corporate finance literature, especially to corporate failure domain
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Verdelli, D. "BIOLOGICAL AND MOLECULAR CHARACTERIZATION OF CMA-03/06, A NEWLY ESTABLISHED INTERLEUKIN-6 INDEPENDENT VARIANT OF THE CMA-03 HUMAN MYELOMA CELL LINE." Doctoral thesis, Università degli Studi di Milano, 2011. http://hdl.handle.net/2434/150553.
Full textAbstract:
The growth and survival of multiple myeloma (MM) cells in the bone marrow microenvironment is regulated by functional complex interactions between the tumor cells and the surrounding bone marrow stromal cells mediated by adhesion molecules and the production of several cytokines of which interleukin-6 (IL-6) has been identified as the most important. Major advances in the investigation of MM biology were made possible by the availability of human myeloma cell lines (HMCLs). The IL-6-dependent CMA-03 cell line was established in our laboratory from a peritoneal effusion of a refractory relapsed MM patient. By gradually decreasing the IL-6 added to the culture, an IL-6-independent variant, CMA-03/06, could be obtained.
The aim of this study was to perform a biological and molecular characterization of this novel cell line and to provide insights into the signaling pathways and target genes involved in the growth and survival of CMA-03/06.
The growth, immunophenotypic, cytogenetic and fluorescence in situ hybridization (FISH) characterization of CMA-03/06 cell line was performed by means of standard procedures. IL-6 production into the culture media was determined using a high sensitivity IL-6 specific ELISA. Genome-wide profiling data were generated by means of Affymetrix GeneChip Human Mapping 250K NspI arrays; copy number (CN) alterations were calculated using the DNAcopy Bioconductor package, based on circular binary segmentation method. Global gene expression profiling (GEP) was performed by means of the GeneChip Human Gene 1.0 ST Arrays (Affymetrix); the supervised analyses were done using the rank Prod method and a 2 fold change cut off.
The immunophenotypic analysis of the two cell lines showed a significant difference in the expression of three antigens: CD45 was considerably reduced in CMA-03/06 cells, whereas they were found positive for both chains of IL-6 receptor, CD126 and CD130, almost undetectable in CMA-03. Conventional cytogenetic and FISH analyses did not reveal differences between the 2 HMCLs. Unlike CMA-03, the addition of IL-6 to the culture medium of CMA-03/06 cells or co-culture with multipotent mesenchymal stromal cells did not induce an increase in CMA-03/06 proliferation. IL-6 was not detected in the supernatants from either CMA-03 or CMA-03/06 cell lines within 48 h, suggesting that the IL-6 independence of CMA03/06 cells is not a result of the development of an autocrine IL-6 loop. Nevertheless, IL-6 induced the activation of STAT3 and STAT1 in both cell lines, even if a slight constitutive STAT3 phosphorylation was found in CMA-03/06. The genome-wide analysis allowed the identification of about 100 altered chromosomal regions common to both HMCLs, mostly DNA gains. Comparison of CMA-03/06 and CMA-03 cells evidenced a different CN in only 15 small chromosomal regions, 8 of which did not contain any transcript, whereas few genes were located on the other ones. GEP analysis of CMA-03/06 compared with CMA-03 identified 140 upregulated and 168 downregulated genes, many of which particularly relevant for MM biology, mainly involved in cellular signaling, cell cycle, cell adhesion, cell development, regulation of transcription, immunologic, inflammatory or defense activity, cytokine receptor activity, apoptosis. None of the genes differentially expressed in CMA-03/06 compared with CMA-03 except 2 were positioned on the chromosomal regions showing a different CN. Finally, CMA-03/06 cell line showed a lower susceptibility to camptothecin-induced apoptosis compared to CMA-03 cells.
The novel CMA03/06 cell line may thus represent a suitable model for studies investigating molecular mechanisms involved in clonal evolution towards IL-6 and/or stroma-independent growth and survival of myeloma cells.
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Bribiesca, Argomedo Federico. "Contrôle et stabilité Entrée-Etat en dimension infinie du profil du facteur de sécurité dans un plasma Tokamak." Thesis, Grenoble, 2012. http://www.theses.fr/2012GRENT023/document.
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Dans cette thèse, on s'intéresse au contrôle du profil de facteur de sécurité dans un plasma tokamak. Cette variable physique est liée à plusieurs phénomènes dans le plasma, en particulier des instabilités magnétohydrodynamiques (MHD). Un profil de facteur de sécurité adéquat est particulièrement important pour avoir des modes d'opération avancés dans le tokamak, avec haut confinement et stabilité MHD. Pour cela faire, on se focalise sur la commande du gradient du profil de flux magnétique poloidal dans le tokamak. L'évolution de cette variable est donnée par une équation de diffusion avec des coefficients distribuées et temps-variants. En utilisant des techniques de type Lyapunov et les propriétés de stabilité entrée-état du système on propose une loi de commande robuste qui prend en compte des contraintes non-linéaires dans l'action imposées par la physique des actionneursIn this thesis, we are interested in the control of the safety factor profile or q-profile in a tokamak plasma. This physical quantity has been found to be related to several phenomena in the plasma, in particular magnetohydrodynamic (MHD) instabilities. Having an adequate safety factor profile is particularly important to achieve advanced tokamak operation, providing high confinement and MHD stability. To achieve this, we focus in controlling the gradient of the poloidal magnetic flux profile. The evolution of this variable is given by a diffusion equation with distributed time-varying coefficients. Based on Lyapunov techniques and the Input-to-State stability properties of the system we propose a robust control law that takes into account nonlinear constraints on the control action imposed by the physical actuators
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Boopathy, Sivakumar. "Investigating Structural and Functional Defects in ALS-causing Profilin 1 Variants." eScholarship@UMMS, 2009. http://escholarship.umassmed.edu/gsbs_diss/923.
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Mutations in profilin 1 (PFN1) cause amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disease that targets motor neurons. PFN1 is a 15 kDa protein that is best known for its role in actin dynamics. However, little is known about the pathological mechanisms of PFN1 in ALS. In this dissertation, it is demonstrated that certain familial ALS-linked mutations severely destabilize the native conformation of PFN1 in vitro and cause accelerated turnover of the PFN1 protein in neuronal cells. This mutation-induced destabilization can account for the high propensity of ALS-linked variants to aggregate and also provides rationale for their reported functional defects in cell-based assays. The source of this destabilization is illuminated by the crystal structures of several PFN1 proteins, revealing an expanded cavity near the protein core of one ALS variant and predicting a non-surface exposed cavity in another. Functional biochemical experiments point to abnormalities in actin filament nucleation and elongation caused by PFN1 mutants. In HeLa cells, PFN1 is essential for the generation of actin-rich filopodia and expression of mutant PFN1 alters filopodia density further supporting a pathogenesis mechanism involving actin cytoskeleton. Taken together, this dissertation infers that the pathogenesis of ALS due to mutations in PFN1 can be mediated at least by two possibly related mechanisms, a destabilization of the native PFN1 structure and an impact on the actin assembly processes.
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Boopathy, Sivakumar. "Investigating Structural and Functional Defects in ALS-causing Profilin 1 Variants." eScholarship@UMMS, 2017. https://escholarship.umassmed.edu/gsbs_diss/923.
Full textAbstract:
Mutations in profilin 1 (PFN1) cause amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disease that targets motor neurons. PFN1 is a 15 kDa protein that is best known for its role in actin dynamics. However, little is known about the pathological mechanisms of PFN1 in ALS. In this dissertation, it is demonstrated that certain familial ALS-linked mutations severely destabilize the native conformation of PFN1 in vitro and cause accelerated turnover of the PFN1 protein in neuronal cells. This mutation-induced destabilization can account for the high propensity of ALS-linked variants to aggregate and also provides rationale for their reported functional defects in cell-based assays. The source of this destabilization is illuminated by the crystal structures of several PFN1 proteins, revealing an expanded cavity near the protein core of one ALS variant and predicting a non-surface exposed cavity in another. Functional biochemical experiments point to abnormalities in actin filament nucleation and elongation caused by PFN1 mutants. In HeLa cells, PFN1 is essential for the generation of actin-rich filopodia and expression of mutant PFN1 alters filopodia density further supporting a pathogenesis mechanism involving actin cytoskeleton. Taken together, this dissertation infers that the pathogenesis of ALS due to mutations in PFN1 can be mediated at least by two possibly related mechanisms, a destabilization of the native PFN1 structure and an impact on the actin assembly processes.
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Croizé, Laurence. "Développement et caractérisation d'un spectromètre diode laser pour la mesure en continu et in situ de la composition atmosphérique en 12CO2 et en 13CO2." Paris 6, 2008. http://www.theses.fr/2008PA066571.
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Ce manuscrit présente l'instrument SIMCO (Spectrometer for Isotopic Measurements of CO2) dont le développement s'inscrit dans le contexte scientifique général de l'étude de l'influence des émissions anthropogéniques de gaz à effet de serre sur le climat. La mesure de la concentration totale de CO2 et de la composition isotopique atmosphérique ±13CO2 permet de mieux faire la part entre les processus biogéochimiques et les processus d'origine anthropogénique. Cependant, la très faible amplitude de variation de la composition isotopique dans l'atmosphère implique d'obtenir une exactitude sur la mesure (en unités de ±13C) meilleure que 0,2 ‰ et une excellente stabilité de l'instrument. La problématique de l'augmentation de la concentration de CO2 dans l'atmosphère est exposée en introduction par un bilan des connaissances actuelles que l'on a du cycle du carbone. Puis l'état de l'art de la mesure de gaz à l'état de trace par spectroscopie d'absorption est décrit afin de justifier la configuration expérimentale choisie. Enfin, après avoir rappelé les fondements de la spectroscopie des isotopes du CO2, le montage expérimental retenu et développé, ses performances (et notamment les résultats de deux campagnes de mesures permettant de confronter les mesures de l'instrument SIMCO à celles d'un chromatographe en phase gazeuse et d'un spectromètre de masse) ainsi que les futures améliorations de l'instrument SIMCO sont présentés.
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Bavay, Cécile. "Adaptation des méthodologies d'évaluation sensorielle aux produits agroalimentaires à forte variabilité." Phd thesis, Université d'Angers, 2013. http://tel.archives-ouvertes.fr/tel-00846841.
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Les caractéristiques sensorielles peuvent être mesurées par des méthodes descriptives d'évaluation sensorielle, parmi lesquelles le profil conventionnel. Les résultats sensoriels de profil présentent une forte variabilité, due, d'une part aux différences entre les sujets du panel, et d'autre part à la variabilité intra-lot, et notamment aux différences existant entre les individus d'un échantillon. À ce jour, la variabilité des sujets est prise en compte et les méthodologies de collecte et d'analyse des données ont été adaptées dans ce but. Néanmoins, la variabilité intra-lot n'a pas été abordée, malgré le challenge qu'elle représente. Avec pour produit modèle la pomme, ce travail de thèse aborde la problématique de la variabilité intra-lot sous deux angles : la mesure de la variabilité et la réduction de la variabilité, dans le but d'obtenir une mesure sensorielle plus fiable. Premièrement, la capacité de discrimination du panel a été observée entre les variétés étudiées et entre les fruits de chaque variété, identifiés comme différents selon une mesure instrumentale. Deuxièmement, afin de prendre en compte la variabilité intra-lot, le modèle d'analyse de la variance classiquement utilisé en évaluation sensorielle a été adapté avec l'ajout d'un facteur fruit hiérarchisé au facteur variété. Cette adaptation implique le partage de chaque fruit par plusieurs sujets. L'application de ce modèle a démontré l'importance de la variabilité intra-lot et l'importance du choix du modèle pour obtenir des résultats plus pertinents. De plus, le modèle d'analyse de la variance déterminé a été adapté afin de distinguer désaccord pur entre les sujets et différences de dispersion. Enfin, une réduction de la variabilité effective est obtenue par le partage des fruits ou par une homogénéisation instrumentale, cette dernière étant dépendante de la variété et de la mesure choisie. Les résultats de ce travail apportent des clés méthodologiques pour l'obtention de résultats fiables dans la cadre de l'évaluation sensorielle de produits variables.
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Jakob, Marius. "Methode zur Gestaltung anwendungsabhängiger Mitnehmerverbindungen: Leichtbau und Steigerung der Tragfähigkeit durch dünnwandige Profilwellen." Technische Universität Chemnitz, 2019. https://monarch.qucosa.de/id/qucosa%3A34105.
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Dieser Vortrag beschreibt ein methodisches Vorgehen zur Auslegung von Bauteilen, die von mehreren Eingangsgrößen und mehren Zielgrößen bestimmt sind. Als Praxisbeispiel wird eine dünnwandige Mittnehmerwelle untersucht.
Im Automotivbereich besteht auf Grund der Forderungen nach Leichtbau und höherem Leistungsgewicht verstärkt der Wunsch nach einer hohen Auslastung über das ganze Bauteil hinweg. Eine Gewichtsreduktion kann durch Materialeinsparungen an unkritischen Stellen, wie zum Beispiel im Wellenkern einer Zahnwelle, erreicht werden. Die Verwendung von dünnwandigen Rohren als Ausgangsmaterial, aus denen lastangepasste Zahnprofile umformend hergestellt werden, versprechen eine deutliche Steigerung der Drehmomentübertragbarkeit bezogen auf den Materialeinsatz.
Dazu wird eine neue Verzahnungsgeometrie entwickelt. Das Profil wird über eine Vielzahl an Parametern definiert, welche die Form und damit die Drehmomentübertragbarkeit beeinflussen.
Durch die Verwendung einer bidirektionalen Schnittstelle kann eine Zahn-Geometrie in einem CAD-Programm mit einem FEM-Programm gekoppelt werden. Es zeigt sich, dass sich einige Geometrieparameter bereits durch die Wahl des Ausgangsrohres ergeben oder vorab festgelegt werden können. Mit vorgegebenem Außendurchmesser und Wandstärke des Ausgangsrohres sowie der Zähnezahl verbleiben bei dieser Profilform nur weitere fünf Parameter, welche hinsichtlich der Drehmomentübertragbarkeit zu optimieren sind. Mit Hilfe von numerischen Variantenberechnungen, welche sich nach den Vorgaben eines statistischen Versuchsplanes / Design of Experiments durch Veränderung der Parameter ergeben, kann ein mathematisches Ersatzmodell gebildet werden. Dieses beschreibt die (Wechsel-)Wirkungen der Eingangsgrößen auf die Ausgangsgrößen, wie zum Beispiel der Einfluss des Fußkreisdurchmessers und des Eingriffswinkels auf die dynamische Beanspruchbarkeit. Mit Hilfe von Optimierungsalgorithmen kann ein Optimum der Parameter an Hand des Ersatzmodelles ohne erneute aufwändige FEM-Berechnung gefunden werden.
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Palese, Federico. "Modellazione statica e dinamica di gusci in materiale composito rinforzati da fibre curvilinee: vibrazioni libere, profili di tensione e deformazione, velocità critiche di rotazione." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017.
Find full textAbstract:
Lo scopo di questa tesi è studiare il comportamento statico e dinamico di gusci a singola e doppia curvatura, rinforzati da fibre curvilinee. La tecnologia Variable Angle Tow (VAT) consente la collocazione di fibre lungo percorsi curvilinei allo scopo di migliorare le prestazioni strutturali di piastre e gusci.
Le analisi statiche e dinamiche di diverse strutture sono state risolte con il metodo numerico GDQ.
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Pasmant, Eric. "Neurofibromatose de type 1 : du génotype au phénotype : Etude de l'hétérogénéité génétique et exploration de la composante génétique de l'expressivité variable de la neurofibromatose de type 1." Paris 5, 2010. http://www.theses.fr/2010PA05T020.
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La neurofibromatose de type 1 (NF1) est une maladie héréditaire fréquente transmise sur un mode autosomique dominant à pénétrance complète et qui résulte de l’haploinsuffisance du gène NF1. L’établissement d’une grande cohorte de patients et familles NF1 phénotypés de façon standardisée a constitué un outil unique pour mieux comprendre les bases génétiques de cette maladie complexe. L’existence d’une hétérogénéité génétique a été confirmée par l’identification de patients porteurs de mutation du gène SPRED1 et d’un sous-groupe de patients négatifs pour les gènes NF1 et SPRED1 (5% des cas). L’analyse des corrélations intra familiales de 12 traits phénotypiques de la maladie (5 quantitatifs et 7 binaires) a démontré l’existence de modificateurs génétiques. L’utilisation de la CGH array a confirmé de manière non biaisée l’existence d’un phénotype plus sévère (dysmorphie faciale et difficultés d’apprentissage) associé aux microdélétions du locus NF1 (5% des cas). Enfin, l’analyse de la transmission de SNP du gène NF1 et des caractéristiques phénotypiques au sein des familles de la cohorte, a montré que les allèles du gène NF1 ne participaient pas à la variabilité interindividuelle mais qu’il existait des gènes modificateurs non liés au locus. Pour les identifier, une approche de type gène candidat a été testée en ciblant l’ARN non codant ANRIL situé au locus CDKN2A/B dont des délétions récurrentes ont été retrouvées au sein de neurofibromes plexiformes. Un test d’association sur données familiales a permis de montrer qu’il existait une association significative d’un SNP d’ANRIL avec le nombre de neurofibromes plexiformes. Ces données préliminaires mettent pour la première fois en évidence l’existence d’un gène modificateur dans la NF1, influençant le nombre de neurofibromes plexiformes, symptôme majeur de la maladieNeurofibromatosis 1 (NF1) is a common hereditary disease with an autosomal dominant transmission resulting from gene haploinsufficiency. To evaluate the genetic basis of this complex disease, a vast collection of well-phenotyped ? families was collected through the NF-France Network. Genetic heterogeneity in NF1 was confirmed by (i) identification of patients with SPRED1 mutations and (ii) a sub; patients with no mutation in SPRED1 and NF1 (5% of XF1 patients). A more severe phenotype (facial dysmorphy and learning disabilities) was significantly confirmed in NF1 patients ' NF1 locus microdeletions (5% of NF1 patients) using a custom CGH array. Study of NF1 polymorphisms, analysis of intrafamilial correlations of 12 phenotypic traits, and phenotypes in the c families, allowed us to show that NF1 gene alleles were not implicated in disease variability but provided evidence f< genetic modifiers, unlinked to the NF1 locus. To identify them, a gene candidate approach was used, targeting ANRJj large non coding ARN, located at CDKN2A/B locus that was found deleted in plexiform neurofibromas. Family-base association analysis found a significant association between one SXP ofANRIL and the number of plexiform neurofibromas. These data report for the first time a modifier gene in NF1
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Flih, Sid Ali. "Etude des profils de la raie Hα et de raies atomiques et ioniques de gaz rares émises par des plasmas denses et froids créés dans des tubes à éclairs à remplissage variable (Kr - H2, Ar - H2)." Paris 6, 2003. http://www.theses.fr/2003PA066528.
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Moore, Linda Jennifer. "Impact of Phase Information on Radar Automatic Target Recognition." University of Dayton / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1480434103611127.
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Ravoet, Marie. "Cytogenetic and molecular characterization of CD3-CD4+ T cells from patients with the lymphocytic variant of hypereosinophilic syndrome." Doctoral thesis, Universite Libre de Bruxelles, 2010. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210094.
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La variante lymphocytaire du syndrome hyperéosinophilique (L-SHE) est une pathologie extrêmement rare caractérisée par une prolifération monoclonale de lymphocytes T surproduisant l’interleukine IL-5, responsable d’une hyperéosinophilie persistante. En outre, un immunophénotype aberrant CD3−CD4+ est fréquemment observé à la surface des cellules T clonales. Cette pathologie se distingue par une lymphoprolifération chronique indolente habituellement révélée par une hyperéosinophilie sanguine et une infiltration éosinophilique des tissus cutanés. Toutefois, l’évolution vers un lymphome T observée chez certains patients suggère la présence d’un potentiel malin des cellules T. Ce modèle représente donc une rare opportunité d’identifier les changements moléculaires liés aux différentes étapes du processus transformant lymphoïde T.Dans le cadre de ce travail, nous avons cherché à établir les caractéristiques cytogénétiques et moléculaires des cellules T CD3−CD4+ d’une cohorte de patients L-SHE. L’analyse cytogénétique de cellules T CD3−CD4+ isolées au moment du diagnostic chez deux patientes (P1 et P2) a révélé la présence d’une délétion similaire 6q13-q22.1. En étudiant les stades cliniques successifs de P1 et P2, nous avons montré la persistance des cellules porteuses de la délétion 6q au cours de la progression chronique et leur prédominance lors du développement d’un lymphome T chez P1. Ces résultats suggèrent l’implication précoce et potentiellement critique de la délétion 6q dans cette pathologie lymphoproliférative T. L’analyse des dérégulations transcriptionnelles résultant de ce remaniement a montré une réduction de l’expression des gènes pro-apototiques BACH2 et PA26 dans les cellules T CD3−CD4+ de P1 et P2. En particulier, BACH2, dont l’expression diminue continuellement au cours de l’évolution de P1, jouerait un rôle oncosuppresseur dans la lymphogenèse T.
Afin d’identifier les modifications moléculaires des cellules T clonales, nous avons analysé l’expression de 95% des gènes humains dans les cellules T CD3−CD4+ de trois patients en phase chronique (P1, P2 et P3). La grande homologie des changements transcriptionnels chez les trois patients indique une altération des mêmes mécanismes moléculaires. Ainsi, un profil immunophénotypique exhaustif, validé chez trois patients supplémentaires, a pu être établi. En outre, les dérégulations des voies apoptotiques, TGFβ ou
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encore de signalisation intracellulaire altèrent l’homéostasie des cellules T CD3−CD4+ pouvant favoriser la perte de la capacité apoptotique et/ou la croissance cellulaire. Cette signature moléculaire a été étendue par l’identification de 20 microARNs dont l’expression est dérégulée dans les cellules T CD3−CD4+ d’une cohorte de 6 patients. Par ailleurs, la modification de l’expression des récepteurs impliqués dans la migration leucocytaire au cours de l’évolution de P1 pourrait expliquer l’infiltration ganglionnaire des cellules T clonales et la progression du lymphome.
La caractérisation des désordres cytogénétiques et moléculaires des cellules T CD3−CD4+ chez les patients L-SHE permettrait à terme d’identifier de nouveaux marqueurs diagnostiques et contribuer ainsi au développement de nouvelles cibles thérapeutiques dans une grande diversité de pathologies lymphoprolifératives de type Th2.
Doctorat en Sciences biomédicales et pharmaceutiques
info:eu-repo/semantics/nonPublished
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Fabien, Bernard. "IDADIGE : Procédé de traitement des images de gels d'électrophorèse bidimensionnelle différentielle dans le contexte de la recherche de marqueurs protéiques." Phd thesis, Ecole Nationale Supérieure des Mines de Saint-Etienne, 2008. http://tel.archives-ouvertes.fr/tel-00799838.
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Le sujet de cette thèse s'inscrit dans le cadre du projet NODDICCAP initié par l'entreprise bioMérieux et visant le développement de Nouveaux Outils pour le Dépistage, le DIagnostic, l'évaluation du pronostic et le suivi du Cancer Colorectal par une Approche Protéomique. Le développement de ces nouveaux outils passe nécessairement par l'identification de marqueurs tumoraux discriminants et spécifiques du cancer colorectal. L'objectif de la thèse a été d'optimiser l'analyse des images et des données issues de la technologie DIGE (Differential In-Gel Electrophoresis), afin de permettre la découverte de marqueurs potentiels du cancer colorectal. Après avoir identifié les maillons faibles de la chaîne de traitement classique des images de gel d'électrophorèse 2D, nous avons été amenés à reconsidérer les approches utilisées et à rechercher des méthodes de traitement d'image et de données innovantes, ou bien existantes mais issues de domaines voisins. Le choix des méthodes a été guidé par l'évaluation de leur efficacité en comparaison aux méthodes classiquement employées, et également par les contraintes liées au contexte biologique et technologique. Les principales avancées issues de ce travail sont la définition du schéma expérimental, l'approche stratégique de l'analyse d'images ainsi que l'analyse statistique des données. En ce qui concerne le schéma expérimental, le choix d'une lignée cellulaire comme standard commun a permis un meilleur recoupement des données entre différentes expériences. L'analyse stratégique de l'analyse d'image a été améliorée grâce à l'utilisation d'un patron de détection unique. Ce patron unique a été réalisé à l'aide d'une méthode de fusion d'images originale permettant une juste représentativité de chacune des tâches protéiques de l'ensemble des images considérées. Enfin, les méthodes pour l'analyse statistique des données ont tenu compte de l'intensité des tâches protéiques grâce à une régulation de la variance lors de la comparaison des ratios. Par ailleurs, la spécification par le biologiste d'un profil de risque a permis, par exemple, de porter une plus grande attention aux protéines fortement exprimées. L'ensemble des méthodes mises en place depuis l'acquisition des images jusqu'à la découverte et la visualisation des marqueurs protéiques potentiels constitue le workflow IDADIGE (Image and Data Analysis for Differential In Gel Electrophoresis). Ce workflow exploite différents logiciels ainsi que plusieurs fonctions implémentées sous Matlab et regroupées sous le nom ProDIGE. L'exploitation par le laboratoire de protéomique de bioMérieux du workflow IDADIGE a été utilisée en routine et a permis la découverte de marqueurs protéiques du cancer colorectal qui doivent maintenant être validés biologiquement.
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Bernard, Fabien. "IDADIGE : Procédé de traitement des images de gels d'électrophorèse bidimensionnelle différentielle dans le contexte de la recherche de marqueurs protéiques." Phd thesis, Ecole Nationale Supérieure des Mines de Saint-Etienne, 2008. http://tel.archives-ouvertes.fr/tel-00509768.
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Le sujet de cette thèse s'inscrit dans le cadre du projet NODDICCAP initié par l'entreprise bio-Mérieux et visant le développement de Nouveaux Outils pour le Dépistage, le DIagnostic, l'évaluation du pronostic et le suivi du Cancer Colorectal par une Approche Protéomique. Le développement de ces nouveaux outils passe nécessairement par l'identification de marqueurs tumoraux discriminants et spécifiques du cancer colorectal. L'objectif de la thèse a été d'optimiser l'analyse des images et des données issues de la technologie DIGE (Differential In-Gel Electrophoresis), afin de permettre la découverte de marqueurs potentiels du cancer colorectal. Après avoir identifié les maillons faibles de la chaîne de traitement classique des images de gel d'électrophorèse 2D, nous avons été amenés à reconsidérer les approches utilisées et à rechercher des méthodes de traitement d'image et de données innovantes, ou bien existantes mais issues de domaines voisins. Le choix des méthodes a été guidé par l'évaluation de leur efficacité en comparaison aux méthodes classiquement employées, et également par les contraintes liées au contexte biologique et technologique. Les principales avancées issues de ce travail sont la définition du schéma expérimental, l'approche stratégique de l'analyse d'images ainsi que l'analyse statistique des données. En ce qui concerne le schéma expérimental, le choix d'une lignée cellulaire comme standard commun a permis un meilleur recoupement des données entre différentes expériences. L'analyse stratégique de l'analyse d'image a été améliorée grâce à l'utilisation d'un patron de détection unique. Ce patron unique a été réalisé à l'aide d'une méthode de fusion d'images originale permettant une juste représentativité de chacune des tâches protéiques de l'ensemble des images considérées. Enfin, les méthodes pour l'analyse statistique des données ont tenu compte de l'intensité des tâches protéiques grâce à une régulation de la variance lors de la comparaison des ratios. Par ailleurs, la spécification par le biologiste d'un profil de risque a permis, par exemple, de porter une plus grande attention aux protéines fortement exprimées. L'ensemble des méthodes mises en place depuis l'acquisition des images jusqu'à la découverte et la visualisation des marqueurs protéiques potentiels constitue le workflow IDADIGE (Image and Data Analysis for Differential In Gel Electrophoresis). Ce workflow exploite différents logiciels ainsi que plusieurs fonctions implémentées sous Matlab et regroupées sous le nom ProDIGE. L'exploitation par le laboratoire de protéomique de bioMérieux du workflow IDADIGE a été utilisée en routine et a permis la découverte de marqueurs protéiques du cancer colorectal qui doivent maintenant être validés biologiquement.
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Andrade, Marta Maria Santos de Jesus. "Programs of profit sharing and results - law n. 10.101/2000 and functional comprometimento in bahian fertilizer industries." Universidade Federal do CearÃ, 2007. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=3529.
Full textAbstract:
nÃo hÃThe objective of the present research is to evaluate the relative importance of the Program of Participation in Profits and Results (PPLR) â Law number 10.101, for the commitment of employees in comparison with other factors of functional commitment. Exploratory and descriptive research was conducted, through case studies, with the use of a questionnaire middle structured questionnaire and an interview by topic with managers of PPLR and employees of the administrative, commercial, and operational areas of two large fertilizer companies in Bahia. The research involved two managers and seventy nine employees. The results were analyzed quantitatively and qualitatively. The research allowed to confirm that in spite of the importance of the PPLR for organizational strategies and objectives, there was no agreement between the companies in what it concerns to the prevalence of the Program when related to factors of affective, normative compromising and other calculatives related in the study. It is suggested that several aspects compete for the dissonance among the case studies researched, as the geographical location, demographic subjects and the style of the administration.
A presente pesquisa tem como objetivo avaliar a importÃncia relativa do Programa de ParticipaÃÃo nos Lucros e Resultados (PPLR) â Lei no. 10.101, para o comprometimento dos empregados em comparaÃÃo com outros fatores de comprometimento funcional. Realizou-se uma pesquisa exploratÃria e descritiva, por meio de estudo de caso mÃltiplo, com a aplicaÃÃo de um questionÃrio semi-estruturado e uma entrevista por pauta, junto a gestores dos PPLR e empregados das Ãreas administrativa, comercial e operacional de duas grandes empresas de fertilizantes da Bahia. A pesquisa envolveu dois gestores e setenta e nove empregados. Os dados foram tratados quantitativa e qualitativamente. A pesquisa permitiu constatar que, apesar da importÃncia dos PPLR para as estratÃgias e objetivos organizacionais, nÃo houve consenso entre as empresas pesquisadas no que concerne à prevalÃncia do Programa quando relacionado com fatores de comprometimento afetivos, normativos e demais calculativos relacionados no estudo. Sugere-se que vÃrios aspectos concorrem para a dissonÃncia entre os estudos de caso pesquisados, como a localizaÃÃo geogrÃfica, questÃes demogrÃficas e o estilo da gestÃo.
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Davies, Leon N., and Edward A. H. Mallen. "Influence of accommodation and refractive status on the peripheral refractive profile." 2009. http://hdl.handle.net/10454/5952.
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AIM: The aim of the study was to determine, objectively and non-invasively, whether changes in accommodative demand modify differentially the peripheral refraction in emmetropic and myopic human eyes. METHODS: Forty subjects (19 male, 21 female) aged 20-30 years (mean 22.7 (SD 2.8) years), 21 emmetropes (mean spherical equivalent refractive error (MSE) -0.13 (SD 0.29) D) and 19 myopes (MSE -2.95 (SD 1.76) D) participated in the study. Ametropia was corrected with soft contact lenses (etafilcon A, 58% water content). Subjects viewed monocularly a stationary, high contrast (85%) Maltese cross at 0.0, 1.0, 2.0 and 3.0 D of accommodative demand and at 0, 10, 20 and 30 degrees field angle (nasal and temporal) through a +3.0 D Badal optical system. Static recordings of the accommodation response were obtained for each accommodative level, at each field angle, with an objective, open-view, infrared optometer. RESULTS: Peripheral mean spherical equivalent (M) data showed that the emmetropic cohort exhibited relative myopic shifts into the periphery, while the myopic group showed hypermetropic shifts. Increasing accommodative demand did not alter the peripheral refractive profile in either the temporal (p = 0.25) or nasal (p = 0.07) periphery with no differential accommodative effect between refractive groups in either the temporal (p = 0.77) or nasal (p = 0.73) field. Significant shifts in the J(0) astigmatic component were seen in the temporal (p<0.0005) and nasal (p<0.0005) fields with increasing eccentricity. Interaction effects between eccentricity and accommodative demand illustrated that increasing accommodative demand significantly altered the peripheral refractive profile in the temporal J(0) astigmatic component (p<0.0005). The nasal periphery, however, failed to show such an effect (p = 0.65). CONCLUSIONS: Alterations in peripheral refraction augmented by changes in ocular accommodation are relatively unaffected by refractive error for young, healthy human eyes.
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Munnik, Engela Elizabeth. "Vrouemisdadiger : 'n ondersoek na die persepsies van 'n groep inwoners van Pretoria." Thesis, 1995. http://hdl.handle.net/10500/17541.
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Text in AfrikaansVrouemisdaad is 'n komplekse sosiale verskynsel. 'n Aspek van vrouemisdaad wat in die onderhawige proef skrif ondersoek word, is om aan die hand van bestaande teoriee te probeer verklaar waarom vroue soveel minder misdaad as mans pleeg. Ten einde antwoorde op die vraag te vind, is 'n kwantitatiewe ondersoek na die gemeenskap se houding rakende die vrouemisdadiger en 'n kwalitatiewe ontleding van die beskikbare literatuur gedoen. 'n Intensiewe verkennende studie van die beskikbare literatuur het getoon dat die gemeenskap, navorsers en akademici bepaalde persepsies huldig oor die vrouemisdadiger wat nie altyd met die werklike beeld strook nie. Alhoewel die getalle van vrouemisdadigers deur die jare toegeneem het, het die tipe misdade wat vroue pleeg weinig verander en die omvang van vrouemisdaad proporsioneel tot die bevolking dieselfde gebly. Geen enkele teorie of benadering op sigself bied 'n algemene verklaring vir die verskynsel van vrouemisdaad nie; dit kan hoogstens as gedeeltelike verklaring dien. 'n Algemene verklaringsmodel vir vrouemisdaad is egter opgestel wat terselfdertyd as samevatting van die geselekteerde teoriee dien. Met behulp van die argivale metode is 'n profiel van die gekommitteerde vrouemisdadiger saamgestel om 'n basiese kennissisteem van die vrouemisdadiger daar te stel. Statisties beduidende verbande is gevind tussen die karakteristieke van die blanke gekommitteerde vrouemisdadiger se huwelikstaat, aantal kinders en bedrog. Die kwantitatiewe ondersoek bestaan uit die ontleding van 516 respondente se persepsies oor die vrouemisdadiger. Uit die resultate van verskeie statistiese tegnieke blyk dit dat die ondersoekgroep, wat blanke respondente van vier voorstede uit struktuurstreekplansel 22 van Pretoria verteenwoordig, bepaalde persepsies en opvattings aangaande die vrouemisdadiger het. Die persepsiemeting het aan die lig gebring dat daar verskille in persepsies bestaan oor die vrouemisdadiger en vrouemisdaad in die blanke gemeenskap bestaan. Hierdie persepsies stem nie ooreen met die beeld wat blyk uit die onderhawige navorsing nie. Statisties beduidende verskille in persepsies tussen manlike en vroulike respondente van die ondersoekgroep is ook gevind. Daar bestaan verder statisties beduidende verskille tussen respondente van verskillende voorstede, onderwyspeile, taalgroepe, en ouderdomsgroepe.
It can be said that female crime is a complex phenomenon. An aspect of female crime that is investigated in this thesis is to explain, with reference to existing theories, why women commit fewer crimes than men. In an attempt to answer this question, a quantitative investigation regarding the attitude of society towards the female criminal as well as a qualitative study of the available literature, was conducted. An intensive exploratory study on female crime indicated that and academics have a certain of the available the community, perception of literature researchers the female criminal which does not always correspond with the facts. Although the number of female criminals has increased through the years the extent of female crime, proportionally to the population size, has remained constant, and the type of crime committed by women has remained relatively unchanged. It seems clear that no single theory or approach can explain female crime, it can at best give a partial explanation. An integrated explanation model for female crime has been compiled which simultaneously serves as a summary of selected theories. By means of the archival research method a profile of the female prisoner was compiled, to be used as a basis for the researcher's scientific knowledge of this phenomenon. Statistically significant relations were found to exist between the characteristics of the white female prisoner's marital status, number of children and fraud. The quantitative investigation consisted of an analysis of the responses of 516 respondents on an attitude scale. The results of various statistical techniques show that the research group, which represents respondents fr6m four suburbs from structure plan cell 22 of Pretoria, reveals certain attitudes and beliefs about the female criminal. This attitude measurement indicated that differences in perceptions regarding the female in the white community do criminal and female exist. Furthermore crime these perceptions do not correlate on the female criminal in with the information gathered this research. Statistically significant differences in attitude were found between male and female respondents, respondents from the different suburbs, with different qualifications, of different language groups, and of different age groups.
Sociology
D. Lit. et Phil. (Kriminologie)
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Lin, Yu-Kai, and 林鈺凱. "Flexible roll forming machine design for structural parts with variable profile sections." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/vxt725.
Full textAbstract:
碩士國立高雄應用科技大學
模具工程系
104
Flexible roll forming is able to make products with variable width in the longitudinal direction instead of fixed section profile products made by conventional roll forming process. This paper surveyed the exist patents of flexible roll forming machines and proposed a design around machine design. The design methods of the major mechanisms and structures of a flexible roll forming machine was established. A U-shaped product with variable width in the longitudinal direction was adopted to demonstrate the forming path design of the flexible roll forming process. The maximum loads of each station were obtained via the FEM simulation. The dimensions of structure components and the specifications of the motion units were determined using the established design method. The results of forming simulation showed the springback angles varied with respect to the different section locations. The compensation must be made to get the product satisfy with the requirement of geometry precision. The Solidworks software was adopted to analyze the motion path of the designed roll forming machine. The exported path of the roll motion was in good agreement with the profile variation of the product. This verification showed the feasibility of the proposed machine design method. The flexible roll forming machine was designed and built according to the calculation of component strength using the forming loads of the process simulations. The experiment tests of the one station machine showed the forming path design and the motion control model were as good as respect.
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Chao, Po-Kai, and 趙柏凱. "Development of New Claw Rotor Profiles with Variable Trochoid Ratio Epicycloid Curves." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/54562654906369814626.
Full textAbstract:
碩士國立臺灣大學
機械工程學研究所
101
This thesis develops design methods for new claw rotor profiles with variable trochoid ratio epicycloid curves. Each claw profile of a rotor consists of an epitrochoid, two arcs, an epicycloid with variable trochoid ratio, and a conjugate curve corresponding to the epicycloid. The rotor profile consists of several identical claws and the claw rotor pair consists of two identical rotor profiles. The profile of a single claw is determined by four basic design parameters and one adjusting coefficient. The four basic design parameters include pitch radius, rotor radius, number of claws and a conformity angle. The adjusting coefficient with value between 0 and 1 is used for adjusting the smoothness of the claw rotor profile. Two types of modified claw-shape are also proposed, one uses portion of a cycloid gear tooth profile, the other uses portion of a modified cycloid gear tooth profile. The proposed modified claw-shape has better sealing property between rotors than the similar types of modified claw-shape. The proposed modified claw-shapes can avoid the crash and locking between the rotor pair because of the smooth contour.