890 resultados para Applied behaviour analysis
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La Cadena Datos-Información-Conocimiento (DIC), denominada “Jerarquía de la Información” o “Pirámide del Conocimiento”, es uno de los modelos más importantes en la Gestión de la Información y la Gestión del Conocimiento. Por lo general, la estructuración de la cadena se ha ido definiendo como una arquitectura en la que cada elemento se levanta sobre el elemento inmediatamente inferior; sin embargo no existe un consenso en la definición de los elementos, ni acerca de los procesos que transforman un elemento de un nivel a uno del siguiente nivel. En este artículo se realiza una revisión de la Cadena Datos-Información-Conocimiento examinando las definiciones más relevantes sobre sus elementos y sobre su articulación en la literatura, para sintetizar las acepciones más comunes. Se analizan los elementos de la Cadena DIC desde la semiótica de Peirce; enfoque que nos permite aclarar los significados e identificar las diferencias, las relaciones y los roles que desempeñan en la cadena desde el punto de vista del pragmatismo. Finalmente se propone una definición de la Cadena DIC apoyada en las categorías triádicas de signos y la semiosis ilimitada de Peirce, los niveles de sistemas de signos de Stamper y las metáforas de Zeleny.
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Abstract: Adsorption behaviour of reactive dyes in fixed-bed adsorber was evaluated in this work. The characteristics of mass transfer zone (MTZ), where adsorption in column occurs, were affected by carbon bed depth and influent dye concentration. The working lifetime (t(x)) of MTZ, the height of mass transfer zone (HMTZ), the rate of mass transfer zone (RMTZ), and the column capacity at exhaustion (q(column)) were estimated for the removal of remazol reactive yellow and remazol reactive black by carbon adsorber. The results showed that column capacity calculated at 90% of column exhaustion was lower than carbon capacity obtained from equilibrium studies. This indicated that the capacity of activated carbon was not fully utilized in the fixed-bed adsorber. The bed-depth service time model (BDST) was applied for analysis of reactive yellow adsorption in the column. The adsorption capacity of reactive yellow calculated at 50% breakthrough point (No) was found to be 0.1 kg kg(-1) and this value is equivalent to about 14% of the available carbon capacity. The results of this study indicated the applicability of fixed-bed adsorber for removing remazol reactive yellow from solution. (C) 2008 Elsevier B.V. All rights reserved.
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This letter derives mathematical expressions for the received signal-to-interference-plus-noise ratio (SINR) of uplink Single Carrier (SC) Frequency Division Multiple Access (FDMA) multiuser MIMO systems. An improved frequency domain receiver algorithm is derived for the studied systems, and is shown to be significantly superior to the conventional linear MMSE based receiver in terms of SINR and bit error rate (BER) performance.
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Helicobacter pylori is a bacterial pathogen that affects more than half of the world’s population with gastro-intestinal diseases and is associated with gastric cancer. The cell surface of H. pylori is decorated with lipopolysaccharides (LPSs) composed of three distinct regions: a variable polysaccharide moiety (O-chain), a structurally conserved core oligosaccharide, and a lipid A region that anchors the LPS to the cell membrane. The O-chain of H. pylori LPS, exhibits unique oligosaccharide structures, such as Lewis (Le) antigens, similar to those present in the gastric mucosa and are involved in interactions with the host. Glucan, heptoglycan, and riban domains are present in the outer core region of some H. pylori LPSs. Amylose-like glycans and mannans are also constituents of some H. pylori strains, possibly co-expressed with LPSs. The complexity of H. pylori LPSs has hampered the establishment of accurate structure-function relationships in interactions with the host, and the design of carbohydrate-based therapeutics, such as vaccines. Carbohydrate microarrays are recent powerful and sensitive tools for studying carbohydrate antigens and, since their emergence, are providing insights into the function of carbohydrates and their involvement in pathogen-host interactions. The major goals of this thesis were the structural analysis of LPSs from H. pylori strains isolated from gastric biopsies of symptomatic Portuguese patients and the construction of a novel pathogen carbohydrate microarray of these LPSs (H. pylori LPS microarray) for interaction studies with proteins. LPSs were extracted from the cell surface of five H. pylori clinical isolates and one NCTC strain (26695) by phenol/water method, fractionated by size exclusion chromatography and analysed by gas chromatography coupled to mass spectrometry. The oligosaccharides released after mild acid treatment of the LPS were analysed by electrospray mass spectrometry. In addition to the conserved core oligosaccharide moieties, structural analyses revealed the presence of type-2 Lex and Ley antigens and N-acetyllactosamine (LacNAc) sequences, typically found in H. pylori strains. Also, the presence of O-6 linked glucose residues, particularly in LPSs from strains 2191 and NCTC 26695, pointed out to the expression of a 6-glucan. Other structural domains, namely ribans, composed of O-2 linked ribofuranose residues were observed in the LPS of most of H. pylori clinical isolates. For the LPS from strain 14382, large amounts of O-3 linked galactose units, pointing to the occurrence of a galactan, a domain recently identified in the LPS of another H. pylori strain. A particular feature to the LPSs from strains 2191 and CI-117 was the detection of large amounts of O-4 linked N-acetylglucosamine (GlcNAc) residues, suggesting the presence of chitin-like glycans, which to our knowledge have not been described for H. pylori strains. For the construction of the H. pylori LPS microarray, the structurally analysed LPSs, as well as LPS-derived oligosaccharide fractions, prepared as neoglycolipid (NGL) probes were noncovalently immobilized onto nitrocellulosecoated glass slides. These were printed together with NGLs of selected sequence defined oligosaccharides, bacterial LPSs and polysaccharides. The H. pylori LPS microarray was probed for recognition with carbohydratebinding proteins (CBPs) of known specificity. These included Le and blood group-related monoclonal antibodies (mAbs), plant lectins, a carbohydratebinding module (CBM) and the mammalian immune receptors DC-SIGN and Dectin-1. The analysis of these CBPs provided new information that complemented the structural analyses and was valuable in the quality control of the constructed microarray. Microarray analysis revealed the occurrence of type-2 Lex and Ley, but not type-1 Lea or Leb antigens, supporting the results obtained in the structural analysis. Furthermore, the H. pylori LPSs were recognised by DC-SIGN, a mammalian lectin known to interact with this bacterium through fucosylated Le epitopes expressed in its LPSs. The -fucose-specific lectin UEA-I, showed restricted binding to probes containing type-2 blood group H sequence and to the LPSs from strains CI-117 and 14382. The presence of H-type-2, as well Htype- 1 in the LPSs from these strains, was confirmed using specific mAbs. Although H-type-1 determinant has been reported for H. pylori LPSs, this is the first report of the presence of H-type-2 determinant. Microarray analysis also revealed that plant lectins known to bind 4-linked GlcNAc chitin oligosaccharide sequences bound H. pylori LPSs. STL, which exhibited restricted and strong binding to 4GlcNAc tri- and pentasaccharides, differentially recognised the LPS from the strain CI-117. The chitin sequences recognised in the LPS could be internal, as no binding was detected to this LPS with WGA, known to be specific for nonreducing terminal of 4GlcNAc sequence. Analyses of the H. pylori LPSs by SDS-PAGE and Western blot with STL provided further evidence for the presence of these novel domains in the O-chain region of this LPS. H. pylori LPS microarray was also applied to analysis of two human sera. The first was from a case infected with H. pylori (H. pylori+ CI-5) and the second was from a non-infected control.The analysis revealed a higher IgG-reactivity towards H. pylori LPSs in the H. pylori+ serum, than the control serum. A specific IgG response was observed to the LPS isolated from the CI-5 strain, which caused the infection. The present thesis has contributed to extension of current knowledge on chemical structures of LPS from H. pylori clinical isolates. Furthermore, the H. pylori LPS microarray constructed enabled the study of interactions with host proteins and showed promise as a tool in serological studies of H. pyloriinfected individuals. Thus, it is anticipated that the use of these complementary approaches may contribute to a better understanding of the molecular complexity of the LPSs and their role in pathogenesis.
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Background: Lung cancer (LC) is the leading cause of cancer death in the developed world. Most cancers are associated with tobacco smoking. A primary hope for reducing lung cancer has been prevention of smoking and successful smoking cessation programs. To date, these programs have not been as successful as anticipated. Objective: The aim of the current study was to evaluate whether lung cancer screening combining low dose computed tomography with autofluorescence bronchoscopy (combined CT & AFB) is superior to CT or AFB screening alone in improving lung cancer specific survival. In addition, the extent of improvement and ideal conditions for combined CT & AFB screening were evaluated. Methods: We applied decision analysis and Monte Carlo simulation modeling using TreeAge Software to evaluate our study aims. Histology- and stage specific probabilities of lung cancer 5-year survival proportions were taken from Surveillance and Epidemiologic End Results (SEER) Registry data. Screeningassociated data was taken from the US NCI Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial (PLCO), National Lung Screening Trial (NLST), and US NCI Lung Screening Study (LSS), other relevant published data and expert opinion. Results: Decision Analysis - Combined CT and AFB was the best approach at Improving 5-year survival (Overall Expected Survival (OES) in the entire screened population was 0.9863) and in lung cancer patients only (Lung Cancer Specific Expected Survival (LOSES) was 0.3256). Combined screening was slightly better than CT screening alone (OES = 0.9859; LCSES = 0.2966), and substantially better than AFB screening alone (OES = 0.9842; LCSES = 0.2124), which was considerably better than no screening (OES = 0.9829; LCSES = 0.1445). Monte Carlo simulation modeling revealed that expected survival in the screened population and lung cancer patients is highest when screened using CT and combined CT and AFB. CT alone and combined screening was substantially better than AFB screening alone or no screening. For LCSES, combined CT and AFB screening is significantly better than CT alone (0.3126 vs. 0.2938, p< 0.0001). Conclusions: Overall, these analyses suggest that combined CT and AFB is slightly better than CT alone at improving lung cancer survival, and both approaches are substantially better than AFB screening alone or no screening.
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Objectifs : Ce mémoire propose de répertorier par une revue systématique les instruments de mesure clinique des conduites addictives établies et émergentes; de les comparer au moyen d’une grille d’analyse afin de de déterminer si ces conduites sont cohésives au plan conceptuel. Méthode : La stratégie analytique employée s’est déroulée en trois étapes : 1) Via les moteurs de recherche Pubmed, Psychinfo, HAPI et Embase, nous avons cherché, pour l’ensemble des conduites addictives, les questionnaires ayant fait l’objet d’une étude de validation interne au plan psychométrique. 2) Une grille d’analyse a été développée et validée, couvrant 21 paramètres tirés de 4 catégories conceptuelles : les critères diagnostiques de dépendance (DSM-IVTR), le tempérament (Cloninger et Zuckerman), le processus de production du handicap social (Fougeyrollas) et une grille d’analyse cognitivo-comportementale (Beck). 3) tous les instruments ont été analysés et comparés au moyen de cette grille qui a été développée est validée par un accord inter-juge élevé. Résultats : Nous avons répertorié 191 questionnaires répartis sur 21 conduites addictives. On constate que les conduites les plus prévalentes sont également celles pour lesquelles on retrouve le plus grand nombre de questionnaires. Les catégories que les questionnaires évaluent le plus sont celles des critères de la dépendance et l’analyse cognitivo-comportementale, les catégories beaucoup moins bien représentées étant celles du tempérament et du processus de production du handicap social. On note des tendances semblables pour les paramètres entre les questionnaires portant sur la toxicomanie et ceux portant sur les addictions sans drogues. Conclusion : Ce mémoire confirme une cohésion clinique dans la mesure des addictions, tel que déterminé par une grille validée appliquée sur un ensemble exhaustif de questionnaires répertoriés par une revue systématique.
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Le nombre important de véhicules sur le réseau routier peut entraîner des problèmes d'encombrement et de sécurité. Les usagers des réseaux routiers qui nous intéressent sont les camionneurs qui transportent des marchandises, pouvant rouler avec des véhicules non conformes ou emprunter des routes interdites pour gagner du temps. Le transport de matières dangereuses est réglementé et certains lieux, surtout les ponts et les tunnels, leur sont interdits d'accès. Pour aider à faire appliquer les lois en vigueur, il existe un système de contrôles routiers composé de structures fixes et de patrouilles mobiles. Le déploiement stratégique de ces ressources de contrôle mise sur la connaissance du comportement des camionneurs que nous allons étudier à travers l'analyse de leurs choix de routes. Un problème de choix de routes peut se modéliser en utilisant la théorie des choix discrets, elle-même fondée sur la théorie de l'utilité aléatoire. Traiter ce type de problème avec cette théorie est complexe. Les modèles que nous utiliserons sont tels, que nous serons amenés à faire face à des problèmes de corrélation, puisque plusieurs routes partagent probablement des arcs. De plus, puisque nous travaillons sur le réseau routier du Québec, le choix de routes peut se faire parmi un ensemble de routes dont le nombre est potentiellement infini si on considère celles ayant des boucles. Enfin, l'étude des choix faits par un humain n'est pas triviale. Avec l'aide du modèle de choix de routes retenu, nous pourrons calculer une expression de la probabilité qu'une route soit prise par le camionneur. Nous avons abordé cette étude du comportement en commençant par un travail de description des données collectées. Le questionnaire utilisé par les contrôleurs permet de collecter des données concernant les camionneurs, leurs véhicules et le lieu du contrôle. La description des données observées est une étape essentielle, car elle permet de présenter clairement à un analyste potentiel ce qui est accessible pour étudier les comportements des camionneurs. Les données observées lors d'un contrôle constitueront ce que nous appellerons une observation. Avec les attributs du réseau, il sera possible de modéliser le réseau routier du Québec. Une sélection de certains attributs permettra de spécifier la fonction d'utilité et par conséquent la fonction permettant de calculer les probabilités de choix de routes par un camionneur. Il devient alors possible d'étudier un comportement en se basant sur des observations. Celles provenant du terrain ne nous donnent pas suffisamment d'information actuellement et même en spécifiant bien un modèle, l'estimation des paramètres n'est pas possible. Cette dernière est basée sur la méthode du maximum de vraisemblance. Nous avons l'outil, mais il nous manque la matière première que sont les observations, pour continuer l'étude. L'idée est de poursuivre avec des observations de synthèse. Nous ferons des estimations avec des observations complètes puis, pour se rapprocher des conditions réelles, nous continuerons avec des observations partielles. Ceci constitue d'ailleurs un défi majeur. Nous proposons pour ces dernières, de nous servir des résultats des travaux de (Bierlaire et Frejinger, 2008) en les combinant avec ceux de (Fosgerau, Frejinger et Karlström, 2013). Bien qu'elles soient de nature synthétiques, les observations que nous utilisons nous mèneront à des résultats tels, que nous serons en mesure de fournir une proposition concrète qui pourrait aider à optimiser les décisions des responsables des contrôles routiers. En effet, nous avons réussi à estimer, sur le réseau réel du Québec, avec un seuil de signification de 0,05 les valeurs des paramètres d'un modèle de choix de routes discrets, même lorsque les observations sont partielles. Ces résultats donneront lieu à des recommandations sur les changements à faire dans le questionnaire permettant de collecter des données.
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Skinner's approach to verbal behaviour (language) is central to behaviour analysis, as a philosophy of science, and, increasingly in application, including interventions for autism and challenging behaviour. This PowerPoint show provides an advanced undergraduate level introduction to the basic concepts of Skinner's functional approach to understanding verbal behaviour.
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Capturing the pattern of structural change is a relevant task in applied demand analysis, as consumer preferences may vary significantly over time. Filtering and smoothing techniques have recently played an increasingly relevant role. A dynamic Almost Ideal Demand System with random walk parameters is estimated in order to detect modifications in consumer habits and preferences, as well as changes in the behavioural response to prices and income. Systemwise estimation, consistent with the underlying constraints from economic theory, is achieved through the EM algorithm. The proposed model is applied to UK aggregate consumption of alcohol and tobacco, using quarterly data from 1963 to 2003. Increased alcohol consumption is explained by a preference shift, addictive behaviour and a lower price elasticity. The dynamic and time-varying specification is consistent with the theoretical requirements imposed at each sample point. (c) 2005 Elsevier B.V. All rights reserved.
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In this paper we study the Lyapunov stability and Hopf bifurcation in a biological system which models the biological control of parasites of orange plantations. (c) 2007 Elsevier Ltd. All rights reserved.
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Nesta Tese foram apresentadas algumas alternativas de antecipação do preço futuro do aço a partir do emprego de modelos econométricos. Estes modelos foram definidos em função da análise do comportamento, no longo prazo, entre as séries de preços do aço no Brasil vis-à-vis seus respectivos preços no exterior. A verificação deste comportamento de longo prazo foi realizada através do teste de cointegração. A partir da constatação da não cointegração dessas séries, foram definidos dois modelos, cujas previsões, para diversos períodos, foram aqui apresentadas. Foi feita uma análise comparativa, onde foram identificados o melhor modelo e para quais temporalidades de previsão são melhor empregados. Como foi aqui comprovado, o aço é um insumo primordial nos empreendimentos industriais. Considerando que, atualmente, os preços são demandados de forma firme, ou seja, sem possibilidade de alteração, faz-se necessária a identificação de mecanismos de antecipação dos movimentos futuros desta commodity, de modo que se possa considerá-los na definição do preço ofertado, reduzindo assim perdas por suas flutuações inesperadas.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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The purpose of this study is to present a position based tetrahedral finite element method of any order to accurately predict the mechanical behavior of solids constituted by functionally graded elastic materials and subjected to large displacements. The application of high-order elements makes it possible to overcome the volumetric and shear locking that appears in usual homogeneous isotropic situations or even in non-homogeneous cases developing small or large displacements. The use of parallel processing to improve the computational efficiency, allows employing high-order elements instead of low-order ones with reduced integration techniques or strain enhancements. The Green-Lagrange strain is adopted and the constitutive relation is the functionally graded Saint Venant-Kirchhoff law. The equilibrium is achieved by the minimum total potential energy principle. Examples of large displacement problems are presented and results confirm the locking free behavior of high-order elements for non-homogeneous materials. (C) 2011 Elsevier B.V. All rights reserved.