Ultrasonic Fatigue Analysis on Steel Specimen with Temperature Control : Evaluation of Variable Temperature Effect

Non peer reviewe

A trajetoria do fundador da cidade de Montalvânia na memoria coletiva : uma contribuiçao para a cultura local e escolar

L'objectif de cette étude est d'identifier les éléments présents dans la mémoire collective des habitants de la ville de Montalvania (située au nord de la Province de Minas Gerais, Brésil) autour des événements qui ont eu comme centrale la figure du fondateur de la ville. On a choisi l'option méthodologique de l'histoire orale dans une perspective qualitative, en cherchant la valorisation du sujet humain comme interprète du monde qui l'entoure et comme producteur des significations sociales. Nous avons écouté des gens qui font partie du projet de construction et de développement de Montalvania, ceux qui ont été engagés dans les projets et dans les activités de Antonio Montalvão, le fondateur de la ville, dans la lutte contre le "coronelisme" local. Ils racontent cette histoire, parce qu'ils ont la caractéristique de gardiens de l'histoire. Le fondement théorique est basé surtout en Paul Thompson, Alfredo Bosi et Ecléa Bosi, qui font des rapports, dans leurs études, entre le passé et le présent. Et Raphaël Samuel, Pierre Nora et Jacques Le Goff, préoccupés par la reconstruction de la mémoire et de l'histoire. On souhaite encore que cette étude de re-construction de la mémoire collective, édifiée dans les valeurs présents dans les spécificités locales contribue aux processus culturel et éducationnel local

Essays on Complementarities in Bipartite Matching and in Policy Combination

This dissertation contains three essays on the implications of complementarities on the equilibrium sorting in the marriage market, and on the optimal bundling of different development policies. This first chapter develops and tests a model of marital sorting on gender-role attitudes and intrahousehold time allocations with search frictions in the marriage market, and endogenous intrahousehold bargaining power. It is shown that individuals develop a marital taste for similar gender culture partners in order to avoid conflict in decision-making within their future households. This incentive for matching assortatively is stronger for individuals anticipating little say in intrahousehold decision-making. Using data from the British Household Panel Survey, it is shown that the ability that a woman has to guide the extensive margin of her labor market supply according to her own gender-role attitudes, is entirely driven by her search for a same-attitudes partner while in the marriage market. The second chapter provides empirical evidence on whether health education and microfinance act as substitutes or complements in reducing neonatal mortality. Identification exploits the randomized placement of a health educational intervention in rural India, stratified by the presence of a pre-existing microfinance intervention, together with the longitudinal dimension of our dataset. We find that the two interventions substituted each other: both were more effective when offered in isolation then when offered together. Further analysis shows that these interventions operated through different and substitutable channels. The health education intervention increased the adoption of hygienic health behaviours in home deliveries, whereas the microfinance intervention increased payments made to traditional birth attendants. These findings challenge the preconceived policy notion that complementarities between these two ingredients for development call for their joint supply. In contrast, they suggest that policy makers may get more out of each by offering them in isolation to their communities. The final chapter analyses a decentralized two-dimensional marriage market model with transferable utility, where individuals’ attributes are uniformly distributed on the unit square. I first show that matching of likes along both dimensions is the competitive equilibrium when the geometric average within-attribute complementarity is greater than the geometric average between-attribute complementarity. A finding that nests, as a special case, Becker’s assortative matching result, and is in contrast to previous literature suggesting that the concept of assortative matching is not well defined in multi-dimensions. I then show that away from their optimal (similar-type) partners, individuals are willing to compensate mismatches on one of the attributes with opposite mismatches on the other attribute. A finding that in turn sheds new light on the trade-offs that individuals make in less than perfectly competitive multidimensional marriage markets, such as those plagued by search frictions

Identification des coefficients du model MA du canal par sous-estimation de la densité de probabilité du signal reçu

Nous présentons une stratégie d'estimation autodidacte des coefficients d'un canal de communication avec une structure transversale par estimation paramétrique de la densité de probabilité du signal reçu. Pour diminuer le nombre de gaussiennes qui composent cette densité de probabilité, nous proposons un sous-modèle obtenu par regroupement de quelques gaussiennes en une seule avec dispersion non-radiale. Cela engendre une famille d'estimateurs du canal de communication permettant de varier le rapport entre qualité d'estimation et complexité d'estimateur. Quelques résultats de simulation sont aussi présentés en guise d'illustration

In-Service Performance of Emergency Shutdown Valves and Dependent Operational Relationships in the Offshore Oil and Gas Industry

Industrial process plants use emergency shutdown valves (ESDVs) as safety barriers to protect against hazardous events, bringing the plant to a safe state when potential danger is detected. These ESDVs are used extensively in offshore oil and gas processing plants and have been mandated in the design of such systems from national and international standards and legislation. This paper has used actual ESDV operating data from four mid/late life oil and gas production platforms in the North Sea to research operational relationships that are of interest to those responsible for technical management and operation of ESDVs. The first of the two relationships is between the closure time (CT) of the ESDV and the time it remains in the open position, prior to the close command. It has been hypothesised that the CT of the ESDV is affected by the length of time that it has been open prior to being closed (Time since last stroke). In addition to the general analysis of the data series, two sub-categories were created to further investigate this possible relationship for CT and these are “above mean” and “below mean”. The correlations (Pearson’s based) resulting from this analysis are in the “weak” and “very weak” categories. The second relationship investigated was the effect of very frequent closures to assess if this improves the CT. ESDV operational records for six subjects were analysed to find closures that occurred within a twenty-four hour period of each other. However, no discriminating trend was apparent where CT was impacted positively or negatively by the frequent closure group. It was concluded that the variance of ESDV closure time cannot be influenced by the technical management of the ESDV in terms of scheduling the operation of the ESDV

Time-course of sFlt-1 and VEGF-A release in neutropenic patients with sepsis and septic shock: a prospective study

<p>Abstract</p> <p>Background</p> <p>Septic shock is the most feared complication of chemotherapy-induced febrile neutropenia. So far, there are no robust biomarkers that can stratify patients to the risk of sepsis complications. The VEGF-A axis is involved in the control of microvascular permeability and has been involved in the pathogenesis of conditions associated with endothelial barrier disruption such as sepsis. sFlt-1 is a soluble variant of the VEGF-A receptor VEGFR-1 that acts as a decoy receptor down-regulating the effects of VEGF-A. In animal models of sepsis, sFlt-1 was capable to block the barrier-breaking negative effects of VEGF-A and to significantly decrease mortality. In non-neutropenic patients, sFlt-1 has been shown to be a promising biomarker for sepsis severity.</p> <p>Methods</p> <p>We prospectively evaluated concentrations of sFlt-1 and VEGF-A at different time-points during febrile neutropenia, and evaluated the association of these levels with sepsis severity and septic shock development.</p> <p>Results</p> <p>Neutropenic patients that evolved with septic shock (n = 10) presented higher levels of sFlt-1 and VEGF-A measured 48 hours after fever onset than patients with non-complicated sepsis (n = 31) and levels of these biomarkers correlated with sepsis severity scores. Estimation of the diagnostic accuracy of sFlt-1 levels for the discrimination of patients that evolved to septic shock yielded promising results in our study population.</p> <p>Discussion</p> <p>Our data suggest that sFlt-1 and VEGF-A could be useful biomarkers for sepsis severity in patients with febrile neutropenia. In addition, the kinetics of sFlt-1 release in patients that evolve to septic shock suggest that the sFlt-1 could be a salvage compensatory mechanism in patients with septic shock, but that the magnitude of the sFlt-1 release observed in human sepsis is not sufficient to reproduce the beneficial anti-VEGF-A effects observed in animal models of sepsis.</p

Synthesis and biological evaluation of crown ether acyl derivatives

Peer reviewe

Égalisation par prédiction basée sur des réseaux de neurones et des fonctions objectifs obtenues à partir de la divergence de kullback-leibler et du constant modulus

Une structure de filtrage non linéaire pour l'égalisation aveugle est présentée. Cette structure est basée sur un réseau de neurones, ce qui permet l'inclusion de non linéarités dans la structure du filtre. D'autre part, la stratégie d'apprentissage du réseau est séparée en deux parties : une supervisée et l'autre auto-organisée. La divergence de Kullback-Leibler est utilisée comme base pour une fonction de coût d'une règle d'apprentissage auto-organisée, tandis que le critère du « constant modulus » est utilisé dans la partie supervisée. Les résultats des simulations comparent la performance de cette stratégie par rapport aux stratégies classiques d'égalisation adaptative. Les résultats montrent que, pour certains canaux, la stratégie proposée est plus performante que l'égaliseur à retour des décisions (DFE) supervisé

Substitutions near the hemagglutinin receptor-binding site determine the antigenic evolution of influenza A H3N2 viruses in U.S. swine

Swine influenza A virus is an endemic and economically important pathogen in pigs, with the potential to infect other host species. The hemagglutinin (HA) protein is the primary target of protective immune responses and the major component in swine influenza A vaccines. However, as a result of antigenic drift, vaccine strains must be regularly updated to reflect currently circulating strains. Characterizing the cross-reactivity between strains in pigs and seasonal influenza virus strains in humans is also important in assessing the relative risk of interspecies transmission of viruses from one host population to the other. Hemagglutination inhibition (HI) assay data for swine and human H3N2 viruses were used with antigenic cartography to quantify the antigenic differences among H3N2 viruses isolated from pigs in the United States from 1998 to 2013 and the relative cross-reactivity between these viruses and current human seasonal influenza A virus strains. Two primary antigenic clusters were found circulating in the pig population, but with enough diversity within and between the clusters to suggest updates in vaccine strains are needed. We identified single amino acid substitutions that are likely responsible for antigenic differences between the two primary antigenic clusters and between each antigenic cluster and outliers. The antigenic distance between current seasonal influenza virus H3 strains in humans and those endemic in swine suggests that population immunity may not prevent the introduction of human viruses into pigs, and possibly vice versa, reinforcing the need to monitor and prepare for potential incursions