Resolução distribuída de interacções de serviços na Internet

A proliferação da Internet levou ao crescimento substancial do número de serviços disponibilizados em aplicações como Email, VoIP e WWW, que conduziu à inevitável ocorrência de interacções, com comportamentos indesejáveis. A resolução das interacções de serviços na Internet deve obedecer às características deste meio e como tal deve ter uma arquitectura distribuída. O projecto desenvolvido nesta dissertação apresenta uma solução baseada numa arquitectura distribuída, onde cada nó recorre à resolução prestada por um conselheiro[1]. Finalmente é apresentada uma proposta para a implementação do conselheiro com utilização de fórmulas deônticas e assente em tecnologia Java. O funcionamento da solução foi testado e adaptado com a aplicação de correio electrónico JAMES (Java Apache Mail Enterprise Server) da Apache Software Foundation (ASF). Os resultados obtidos demonstraram o funcionamento da solução de acordo com os objectivos do projecto e o desempenho do sistema não comprometeu o nível de serviço da aplicação de Email.info:eu-repo/semantics/publishedVersio

The genetic architecture of the human cerebral cortex

The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area cluster near genes in Wnt signaling pathways, which influence progenitor expansion and areal identity. Variation in cortical structure is genetically correlated with cognitive function, Parkinson's disease, insomnia, depression, neuroticism, and attention deficit hyperactivity disorder

Atributos dos Projectos de Desenvolvimento de Aplicacoes Informaticas

We advocate that, prior the development of computer based systems, attributes (that is the characteristics) of the system and the attributes of the project development must be identified. From an initial list of attributes we must select and refine the required set of attributes in order to achieve a satisfactory use of the different components of the software development project. The different components, such as the process, design methodology and software engineering environments will enable the development of systems holding the required attributes. In this part of this thesis we concentrate on the representation and interpretation of related attributes. Our study is based on the assumption that attributes should not be identified in vacuum, and should be based on the different classes of relationships between attributes of computer applications and attributes of the development of computer applications. Relationships between attributes follow a number of rules to be presented in this thesis. Attributes and relationships between attributes are used as the basis of one method to select the best proposals for every component of projects of software development. The second part of this thesis focuses on the process of identifying consequence relationships between attributes. We suggest that such processes can be represented by a number of models. We then develop a conceptual scheme to represent models of the process of identifying relationships between attributes. Finally, we adopt the conceptual scheme to represent some novel modelsAvailable from Fundacao para a Ciencia e a Tecnologia, Servico de Informacao e Documentacao, Av. D. Carlos I, 126, 1200 Lisboa / FCT - Fundação para o Ciência e a TecnologiaSIGLEPTPortuga

Distributed Resolution of Feature Interactions for Internet Applications

Internet applications, such as Email, VoIP and WWW, have been enhanced with many features. However, the introduction and modification of features may result in undesired behaviors, and this effect is known as feature interaction-FI. After a brief review of FI detection principles, we propose an interaction resolution adviser, consisting in two phases. The first phase implements an initial selection, by filtering the features that satisfy a set of formulas. We describe several strategies according to the nodes that participate in the FI resolution. The second phase selects the feature for execution, and adapts parameters, according to user policies. The interaction resolution adviser is distributed, scalable and independent of the applications and their features

Weaning from mechanical ventilation in intensive care units across 50 countries (WEAN SAFE): a multicentre, prospective, observational cohort study

Background Current management practices and outcomes in weaning from invasive mechanical ventilation are poorly understood. We aimed to describe the epidemiology, management, timings, risk for failure, and outcomes of weaning in patients requiring at least 2 days of invasive mechanical ventilation. Methods WEAN SAFE was an international, multicentre, prospective, observational cohort study done in 481 intensive care units in 50 countries. Eligible participants were older than 16 years, admitted to a participating intensive care unit, and receiving mechanical ventilation for 2 calendar days or longer. We defined weaning initiation as the first attempt to separate a patient from the ventilator, successful weaning as no reintubation or death within 7 days of extubation, and weaning eligibility criteria based on positive end-expiratory pressure, fractional concentration of oxygen in inspired air, and vasopressors. The primary outcome was the proportion of patients successfully weaned at 90 days. Key secondary outcomes included weaning duration, timing of weaning events, factors associated with weaning delay and weaning failure, and hospital outcomes. This study is registered with ClinicalTrials.gov, NCT03255109. Findings Between Oct 4, 2017, and June 25, 2018, 10 232 patients were screened for eligibility, of whom 5869 were enrolled. 4523 (77·1%) patients underwent at least one separation attempt and 3817 (65·0%) patients were successfully weaned from ventilation at day 90. 237 (4·0%) patients were transferred before any separation attempt, 153 (2·6%) were transferred after at least one separation attempt and not successfully weaned, and 1662 (28·3%) died while invasively ventilated. The median time from fulfilling weaning eligibility criteria to first separation attempt was 1 day (IQR 0–4), and 1013 (22·4%) patients had a delay in initiating first separation of 5 or more days. Of the 4523 (77·1%) patients with separation attempts, 2927 (64·7%) had a short wean (≤1 day), 457 (10·1%) had intermediate weaning (2–6 days), 433 (9·6%) required prolonged weaning (≥7 days), and 706 (15·6%) had weaning failure. Higher sedation scores were independently associated with delayed initiation of weaning. Delayed initiation of weaning and higher sedation scores were independently associated with weaning failure. 1742 (31·8%) of 5479 patients died in the intensive care unit and 2095 (38·3%) of 5465 patients died in hospital. Interpretation In critically ill patients receiving at least 2 days of invasive mechanical ventilation, only 65% were weaned at 90 days. A better understanding of factors that delay the weaning process, such as delays in weaning initiation or excessive sedation levels, might improve weaning success rates