Tesi: "Profil de variance"

1

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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Abstract (sommario):

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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2

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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3

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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Abstract (sommario):

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
The 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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4

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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Abstract (sommario):

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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5

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.

Testo completo

Abstract (sommario):

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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6

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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Abstract (sommario):

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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7

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.

Testo completo

Abstract (sommario):

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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8

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 fournissons
The 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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9

Wells, Patrick Julian. "The rate of profit as a random variable". Thesis, Open University, 2007. http://oro.open.ac.uk/22347/.

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This thesis is a systematic attempt to investigate two conjectures about the distribution of company rates of profit: that it should be log-normal (Gibrat 1931), and that it should be gamma distributed (Farjoun and Machover 1983). A large set of company accounts data is analysed, and partial support found for Gibrat and for a generalised version of Farjoun and Machover. The analysis includes a demonstration of different empirical distributions for different profit rate measures, a demonstration of power law tails in all measures of the profit rate, and a demonstration of size effects (differences in tail weights) in financial ratios. Annual variation in the overall skewness and kurtosis of profit rate distributions is shown to be dominated by variation in the power law tails. L-moments, a recent innovation in robust methods to deal with extreme values, are used in conjunction with a size-weighted sampling scheme to identify possible models for distributions of the profit rate at the capital level. Farjoun and Machover derive their hypothesis from a particular conception of the process of capitalist competition. A rival conception, that of Glick (1985), is tested using company accounts data and shown to be vulnerable to criticism concerning the scope of its data set, the test statistic employed, and its choice of profit rate measure. More fundamentally, it is also dependent on doubtful premises about the within-industry distribution of profit rates, as L-moment analysis demonstrates.

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10

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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11

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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12

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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13

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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14

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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15

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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Abstract (sommario):

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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16

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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17

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 Veterinária
One 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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18

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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Abstract (sommario):

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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19

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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20

Berrett, Candace. "Bayesian Probit Regression Models for Spatially-Dependent Categorical Data". The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1285076512.

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21

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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Abstract (sommario):

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
In 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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22

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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23

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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24

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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Abstract (sommario):

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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25

Alu, Kelechukwu Iroajanma. "Solving the Differential Equation for the Probit Function Using a Variant of the Carleman Embedding Technique". Digital Commons @ East Tennessee State University, 2011. https://dc.etsu.edu/etd/1306.

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Abstract (sommario):

The probit function is the inverse of the cumulative distribution function associated with the standard normal distribution. It is of great utility in statistical modelling. The Carleman embedding technique has been shown to be effective in solving first order and, less efficiently, second order nonlinear differential equations. In this thesis, we show that solutions to the second order nonlinear differential equation for the probit function can be approximated efficiently using a variant of the Carleman embedding technique.

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26

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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27

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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Abstract (sommario):

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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28

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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29

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 (pInfluence of the HMGCoA reductase (HMGCR) and LDL receptor (LDLR) gene polymorphisms on response to atorvastatin (10 mg/day/4weeks) was evaluated in hypercholesterolemic (HC) individuais. Blood samples were collected from 153 HC and 182 normolipidemic (NL) individuais for serum lipids determinations and DNA extratcion. Single nucleotide polymorphisms (SNP) HMGCR (A11898T e T24558G) and LDLR (C16730T, C20001T, G26857A) were detected by PCR-RFLP. HMGCR 11898T and 24558G alleles were associated with lower serum triglycerides and VLDL-C in NL and HC groups (p<0.05). Moreover, the SNP HMGCR T24558G was related to increased serum HDL-C and apoAI in response to atorvastatin in the HC group. The LDLR 20001 C allele was associated with higher basal serum apoAI in the NL group (p=0.034) and with better response of apoAI to atorvastatin in HC group (p=0.045). There was a relationship between heterozygote LDLR 20001 C/16730T haplotype and a significant reduction of apoB and increase in apoAI serum leveis after atorvastatin treatment (p<0.05). In conclusion, the HMGCR A11898T e T24558G SNPs influence serum triglycerides and VLDL-C independently of the lipemic status and LDLR 20001 C/16730T haplotype is associated with better serum apoB and Apol response to atorvastatin treatment.

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30

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 faillite
This 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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Štencl, Roman. "Posouzení vlivu různých variant řešení otopné soustavy na hodnotu bytového domu". Master's thesis, Vysoké učení technické v Brně. Ústav soudního inženýrství, 2017. http://www.nusl.cz/ntk/nusl-320394.

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This master’s thesis deals with influence of heat source on the value of the apartment building. The introduction describes the calculation of heat losses, types of heating systems, heating elements, heat sources for heating and hot water, methods of market valuation. Further are chosen two variants of heat sources for heating and domestic hot water for the Domino apartment building. Both heating elements are designed to cover the heat losses of the house. At the end of the thesis is an evaluation of the return of a more expensive variant, but cheaper to operate, profit from sale and profibility on rent of the apartment building.

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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.

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nÃo hÃ
The 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 Ã 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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Tahsin, Subrina. "Endogenous Risk Perception, Geospatial Characteristics and Temporal Variation in Hurricane Evacuation Behavior". FIU Digital Commons, 2014. http://digitalcommons.fiu.edu/etd/1513.

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The main focus of this thesis was to gain a better understanding about the dynamics of risk perception and its influence on people’s evacuation behavior. Another major focus was to improve our knowledge regarding geo-spatial and temporal variations of risk perception and hurricane evacuation behavior. A longitudinal dataset of more than eight hundred households were collected following two major hurricane events, Ivan and Katrina. The longitudinal survey data was geocoded and a geo-spatial database was integrated to it. The geospatial database was composed of distance, elevation and hazard parameters with respect to the respondent’s household location. A set of Bivariate Probit (BP) model suggests that geospatial variables have had significant influences in explaining hurricane risk perception and evacuation behavior during both hurricanes. The findings also indicated that people made their evacuation decision in coherence with their risk perception. In addition, people updated their hurricane evacuation decision in a subsequent similar event.

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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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35

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 maladie
Neurofibromatosis 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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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.

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Abstract (sommario):

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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38

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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39

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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40

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.

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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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Hirk, Rainer, Kurt Hornik e Laura Vana. "Multivariate Ordinal Regression Models: An Analysis of Corporate Credit Ratings". WU Vienna University of Economics and Business, 2017. http://epub.wu.ac.at/5389/1/Report132_lvana.pdf.

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Correlated ordinal data typically arise from multiple measurements on a collection of subjects. Motivated by an application in credit risk, where multiple credit rating agencies assess the creditworthiness of a firm on an ordinal scale, we consider multivariate ordinal models with a latent variable specification and correlated error terms. Two different link functions are employed, by assuming a multivariate normal and a multivariate logistic distribution for the latent variables underlying the ordinal outcomes. Composite likelihood methods, more specifically the pairwise and tripletwise likelihood approach, are applied for estimating the model parameters. We investigate how sensitive the pairwise likelihood estimates are to the number of subjects and to the presence of observations missing completely at random, and find that these estimates are robust for both link functions and reasonable sample size. The empirical application consists of an analysis of corporate credit ratings from the big three credit rating agencies (Standard & Poor's, Moody's and Fitch). Firm-level and stock price data for publicly traded US companies as well as an incomplete panel of issuer credit ratings are collected and analyzed to illustrate the proposed framework.
Series: Research Report Series / Department of Statistics and Mathematics

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42

Hirk, Rainer, Kurt Hornik e Laura Vana. "Multivariate ordinal regression models: an analysis of corporate credit ratings". Springer Berlin Heidelberg, 2018. http://dx.doi.org/10.1007/s10260-018-00437-7.

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Abstract (sommario):

Correlated ordinal data typically arises from multiple measurements on a collection of subjects. Motivated by an application in credit risk, where multiple credit rating agencies assess the creditworthiness of a firm on an ordinal scale, we consider multivariate ordinal regression models with a latent variable specification and correlated error terms. Two different link functions are employed, by assuming a multivariate normal and a multivariate logistic distribution for the latent variables underlying the ordinal outcomes. Composite likelihood methods, more specifically the pairwise and tripletwise likelihood approach, are applied for estimating the model parameters. Using simulated data sets with varying number of subjects, we investigate the performance of the pairwise likelihood estimates and find them to be robust for both link functions and reasonable sample size. The empirical application consists of an analysis of corporate credit ratings from the big three credit rating agencies (Standard & Poor's, Moody's and Fitch). Firm-level and stock price data for publicly traded US firms as well as an unbalanced panel of issuer credit ratings are collected and analyzed to illustrate the proposed framework.

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Zhang, Angang. "Some Advances in Classifying and Modeling Complex Data". Diss., Virginia Tech, 2015. http://hdl.handle.net/10919/77958.

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In statistical methodology of analyzing data, two of the most commonly used techniques are classification and regression modeling. As scientific technology progresses rapidly, complex data often occurs and requires novel classification and regression modeling methodologies according to the data structure. In this dissertation, I mainly focus on developing a few approaches for analyzing the data with complex structures. Classification problems commonly occur in many areas such as biomedical, marketing, sociology and image recognition. Among various classification methods, linear classifiers have been widely used because of computational advantages, ease of implementation and interpretation compared with non-linear classifiers. Specifically, linear discriminant analysis (LDA) is one of the most important methods in the family of linear classifiers. For high dimensional data with number of variables p larger than the number of observations n occurs more frequently, it calls for advanced classification techniques. In Chapter 2, I proposed a novel sparse LDA method which generalizes LDA through a regularized approach for the two-class classification problem. The proposed method can obtain an accurate classification accuracy with attractive computation, which is suitable for high dimensional data with p>n. In Chapter 3, I deal with the classification when the data complexity lies in the non-random missing responses in the training data set. Appropriate classification method needs to be developed accordingly. Specifically, I considered the "reject inference problem'' for the application of fraud detection for online business. For online business, to prevent fraud transactions, suspicious transactions are rejected with unknown fraud status, yielding a training data with selective missing response. A two-stage modeling approach using logistic regression is proposed to enhance the efficiency and accuracy of fraud detection. Besides the classification problem, data from designed experiments in scientific areas often have complex structures. Many experiments are conducted with multiple variance sources. To increase the accuracy of the statistical modeling, the model need to be able to accommodate more than one error terms. In Chapter 4, I propose a variance component mixed model for a nano material experiment data to address the between group, within group and within subject variance components into a single model. To adjust possible systematic error introduced during the experiment, adjustment terms can be added. Specifically a group adaptive forward and backward selection (GFoBa) procedure is designed to select the significant adjustment terms.
Ph. D.

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Fortin, Myriam. "Comparaison de la performance relative des modèles de régression logistique des cotes proportionnelles et probit pour le cas d'une variable dépendante polytomique ordinale". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq25234.pdf.

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Ferronatto, Júlio César. "A análise da relação custo x volume x lucro : estudo de caso em uma instituição de ensino". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2014. http://hdl.handle.net/10183/109001.

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Abstract (sommario):

Este trabalho teve como objetivo discutir a temática do Custeio Variável aplicado a uma empresa prestadora de serviços, para demonstrar o uso da Margem de Contribuição como ferramenta de apoio à gestão da empresa. A pesquisa aqui relatada utilizou o método qualitativo como abordagem, realizada por meio de um estudo de caso descritivo utilizando como modelo a Análise da relação Custo x Volume x Lucro para empresas multiprodutoras. A fim de possibilitar a realização deste estudo de caso, foi realizada a revisão da literatura sobre o tema, de modo a fundamentar e estruturar as etapas de aplicação do modelo adotado no ambiente organizacional escolhido, analisando-se os serviços prestados pela empresa e identificando-se corretamente a Margem de Contribuição destes. Após esta etapa, foi possível analisar a participação de cada serviço na composição do mix de vendas da empresa e, dessa forma, avaliar a contribuição efetiva de cada um na geração da riqueza para a empresa. O modelo proposto envolve basicamente a identificação da Margem de Contribuição Unitária e sua correspondente Razão de Contribuição, além da identificação do Ponto de Equilíbrio de cada serviço, bem como da empresa como um todo. Esse estudo foi desenvolvido em uma instituição de ensino em fase de crescimento e devido aos desafios que se apresentam a uma empresa nessas condições, aumenta a relevância do mesmo, do ponto de vista do uso de ferramentas de gestão profissionais, que apesar de consagradas no mercado, nem sempre são utilizadas por uma grande parte das pequenas empresas. Ao final, é demonstrada a aplicação do modelo e destacada a sua relevância para a gestão da empresa, bem como, apresentadas as conclusões do estudo, evidenciando-se que por meio da utilização do modelo proposto, os objetivos específicos são atingidos e a indagação feita a cerca da problemática discutida é respondida por meio dos resultados obtidos no presente estudo.
This study aimed to discuss the theme of Variable Costing applied to a service provider, to demonstrate the use of the Contribution Margin as a management support tool company. The research reported here used the qualitative method as approach, performed through a descriptive case study using a model of Analysis of Cost x Volume x Profit respect to multiproducts companies. In order to enable the realization of this case study, the literature review on the subject was held in order to support and structure the application steps of the model adopted in the organizational environment chosen by analyzing the services provided by the company and the correct identification of the contribution margin of these. After this step, it was possible to analyze the participation of each service in the composition of the sales mix of the company and thus evaluate the actual contribution of each in the generation of wealth for the company. The proposed model basically involves identifying the unit contribution margin and it’s corresponding contribution ratio and the identification Breakeven Point each service as well as the company as a whole. This study was developed in an educational institution in the growth phase and due to the challenges that confront the company under these conditions, increases its relevance from the point of view of the use of management tools professionals who consecrated despite the market are not always used by a large proportion of small businesses. At the end, it is demonstrated the application of the model and highlighted its relevance to the company's management, as well as presented the study's findings, showing that by using the proposed model, the specific objectives are met and the question made about the discussed problem is answered by the results obtained in this study.

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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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Barasuol, Edelmar Eloi. "AVALIAÇÃO DOS CRITÉRIOS DO PLANO DE PARTICIPAÇÃO NOS LUCROS POR MEIO DE INDICADORES DE DESEMPENHO". Universidade Federal de Santa Maria, 2006. http://repositorio.ufsm.br/handle/1/8214.

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The present study focuses on the research and evaluation of a profit- and/or result-sharing plan (PRSP) applied during 7 years at the CERTHIL Company. Multi-variable and descriptive analyses were the methods used. The objective of the research was to propose a methodology that would facilitate the implantation and evaluation of future profit-sharing plans at other companies. It is classified as a quantitative study. A questionnaire (Likert scale) was given to directors and collaborators of CERTHIL and directors of the company CERMISSÕES, which intends to implant the PRSP. The evaluation of indicators by the multi-variable analysis allowed for the selection of an ideal group of variables for analysis. The factorial analysis enabled the identification of the degree of importance of each indicator analyzed, facilitating the study of those indicators that have greater and lesser influence in the plan. The analysis of the principal components allowed for the reduction and identification of variables of greater statistical relevance, that better explain the factors to be analyzed and identify those that will maintain greater management control. The methodology proposed proved to be important and highly applicable in the evaluation and implantation of Profit- and/or Result-Sharing plans. This method can be used as a tool to monitor performance indicators applied to the PRSP and contribute to business planning.
O presente estudo concentra-se em uma pesquisa e avaliação do plano de participação nos lucros e resultado PLR aplicado há 7 anos na CERTHIL. Utilizou-se os métodos de análise descritiva e multivariada. O objetivo da pesquisa é avaliar os critérios do PLR por meio dos indicadores de desempenho aplicado aos processos produtivos. Classifica-se como pesquisa quantitativa. Aplicou-se um questionário valendo-se de uma escala Likert onde foi aplicado junto aos gestores e colaboradores da CERTHIL e gestores da CERMISSÕES - que pretende implantar a PLR. A análise descritiva foi útil para fazer o comparativo do entendimento e opinião dos respondentes de ambas as cooperativas sobre a PLR, quanto a sua implantação, influência na qualidade, lucratividade, gestão administrativa, motivação, relacionamento e comprometimento. A avaliação dos indicadores, através da análise multivariada, possibilitou selecionar um grupo ideal de variáveis para análise. A análise fatorial proporcionou a identificação do grau de importância de cada indicador analisado, facilitando o acompanhamento dos indicadores que influenciam em maior e menor importância na composição do plano. A análise de componentes principais possibilita reduzir e identificar as variáveis de maior relevância estatística, que mais expliquem os fatores a serem analisados e identifiquem as que deve manter um maior controle gerencial. Os procedimentos multivariados confirmam sua importância e aplicabilidade na avaliação e implantação de planos de participação nos lucros e resultados nas empresas. Pode-se utilizar,esse método, como ferramenta para monitorar indicadores de desempenho aplicados a PLR e contribuir na gestão administrativa.

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Choudhury, Gias Uddin Ahmed. "Impact of Microcredit Program on Women's Empowerment in Rural Bangladesh". Thesis, Karlstads universitet, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-80192.

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Background – This study is an attempt to explore the relationship between microcredit and the socio-economic empowerment of women in rural Bangladesh. Microcredit is simply the extension of a small amount of collateral-free institutional loans to jointly liable poor group members to generate employment and income enhancing activities. As it is too difficult for poor members to get loan from the formal credit institutions, Grameen Bank (GB) or other Non-Government Organizations (NGOs) provide small loans to vulnerable groups of the society by which they are expected to empower over his counterparts. Research questions – RQ1: How does micro-credit affect different indicators of women empowerment in the rural areas of Bangladesh? RQ2– Is the impact different from the male counterparts in the sample households? Purpose – This study is an effort to find the impact of microcredit on a number of indicators of women’s empowerment in the rural areas in Bangladesh. Methodology – Quantitative Regression Techniques such as Ordinary Least Square (OLS) and Instrumental Variable (IV) method have been applied to get the relationship between microcredit and women empowerment. Conclusion – Applying nationally representative cross-section survey data, Bangladesh Integrated Household Survey (BIHS) 2015, this thesis is intended to find the causal linkage between microcredit and women empowerment’s with different dimensions of women’s decisions are taken as empowerment indicators: production, resources, income, leadership, savings and time. The analysis has been conducted at the household level. The study assumes that women empowerment is endogenous. After controlling for endogeneity in the estimation by using an instrumental variable (IV) ‘distance to the market’ this study finds a significant relationship between microcredit and different dimensions of women’s empowerment. Participation in the microcredit program is found to be significant in explaining some of the outcome indicators of empowerment for the sampled households.

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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.

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Abstract (sommario):

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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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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Tesi sul tema "Profil de variance"

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