Transparent Dynamic reconfiguration for CORBA

Distributed systems with high availability requirements have to support some form of dynamic reconfiguration. This means that they must provide the ability to be maintained or upgraded without being taken off-line. Building a distributed system that allows dynamic reconfiguration is very intrusive to the overall design of the system, and generally requires special skills from both the client and server side application developers. There is an opportunity to provide support for dynamic reconfiguration at the object middleware level of distributed systems, and create a dynamic reconfiguration transparency to application developers. We propose a Dynamic Reconfiguration Service for CORBA that allows the reconfiguration of a running system with maximum transparency for both client and server side developers. We describe the architecture, a prototype implementation, and some preliminary test result

Towards an MDA-based development methodology for distributed applications

This paper proposes a development methodology for distributed applications based on the principles and concepts of the Model-Driven Architecture (MDA). The paper identifies phases and activities of an MDA-based development trajectory, and defines the roles and products of each activity in accordance with the Software Process Engineering Metamodel (SPEM). The development methodology presented in this paper is being developed and applied in the European 5th Framework project MODA-TEL, which aims at assessing the applicability and potential of MDA in the context of telecom services and applications. This paper also discusses the application of the proposed methodology on a typical telecom service case study. The paper claims that the proposed methodology is general enough to be applicable to distributed applications in other domains as well

Relational contexts and conceptual model clustering

In recent years, there has been a growing interest in the use of reference conceptual models to capture information about complex and sensitive business domains (e.g., finance, healthcare, space). These models play a fundamental role in different types of critical semantic interoperability tasks. Therefore, it is essential that domain experts are able to understand and reason with their content. In other words, it is important for these reference conceptual models to be cognitively tractable. This paper contributes to this goal by proposing a model clustering technique that leverages the rich semantics of ontology-driven conceptual models (ODCM). In particular, the technique employs the notion of Relational Context to guide automated model breakdown. Such Relational Contexts capture all the information needed for understanding entities “qua players of roles” in the scope of an objectified (reified) relationship (relator)

Legal Theories and Judicial Decision-Making: An Ontological Analysis

In this paper, we expose the legal theories underlying two important classes of Legal Core Ontologies and show how these ontologies inherit both limitations and benefits (such as explanatory power) of their underlying theories. We do that with the help of a real case study in which we have normative omission and collision of principles. We use this case study to conduct an ontological analysis of the support for judicial decision-making in LKIF-Core (representing Kelsen's Pure Theory of the Law) and UFO-L (representing Robert Alexy's Theory of Constitutional Rights). We show that UFO-L is able to articulate the semantics of the content of judicial decisions by making explicit the individual's legal positions that are raised in argumentation along a legal process. The same cannot be said of LKIF-Core that is based on the Kelsenian stance and focuses on the representation of general norms (norm types) and subsumption of facts to these norms

The upper respiratory tract microbiota of healthy adults is affected by Streptococcus pneumoniae carriage, smoking habits, and contact with children.

BACKGROUND The microbiota of the upper respiratory tract is increasingly recognized as a gatekeeper of respiratory health. Despite this, the microbiota of healthy adults remains understudied. To address this gap, we investigated the composition of the nasopharyngeal and oropharyngeal microbiota of healthy adults, focusing on the effect of Streptococcus pneumoniae carriage, smoking habits, and contact with children. RESULTS Differential abundance analysis indicated that the microbiota of the oropharynx was significantly different from that of the nasopharynx (P < 0.001) and highly discriminated by a balance between the classes Negativicutes and Bacilli (AUC of 0.979). Moreover, the oropharynx was associated with a more homogeneous microbiota across individuals, with just two vs. five clusters identified in the nasopharynx. We observed a shift in the nasopharyngeal microbiota of carriers vs. noncarriers with an increased relative abundance of Streptococcus, which summed up to 30% vs. 10% in noncarriers and was not mirrored in the oropharynx. The oropharyngeal microbiota of smokers had a lower diversity than the microbiota of nonsmokers, while no differences were observed in the nasopharyngeal microbiota. In particular, the microbiota of smokers, compared with nonsmokers, was enriched (on average 16-fold) in potential pathogenic taxa involved in periodontal diseases of the genera Bacillus and Burkholderia previously identified in metagenomic studies of cigarettes. The microbiota of adults with contact with children resembled the microbiota of children. Specifically, the nasopharyngeal microbiota of these adults had, on average, an eightfold increase in relative abundance in Streptococcus sp., Moraxella catarrhalis, and Haemophilus influenzae, pathobionts known to colonize the children's upper respiratory tract, and a fourfold decrease in Staphylococcus aureus and Staphylococcus lugdunensis. CONCLUSIONS Our study showed that, in adults, the presence of S. pneumoniae in the nasopharynx is associated with a shift in the microbiota and dominance of the Streptococcus genus. Furthermore, we observed that smoking habits are associated with an increase in bacterial genera commonly linked to periodontal diseases. Interestingly, our research also revealed that adults who have regular contact with children have a microbiota enriched in pathobionts frequently carried by children. These findings collectively contribute to a deeper understanding of how various factors influence the upper respiratory tract microbiota in adults. Video Abstract

Dynamic reconfiguration for middleware-based applications

Distributed systems with high availability requirements have to allow reconfiguration of the system without being taken off-line. Examples of reconfigurations are the replacement of a component with a newer version, or the migration of a component to another node. A key issue for reconfiguration is maintaining the correctness of the system, which can be very complex due to the number of components, unclear relations between components, heterogeneity in operating systems and programming languages, and physical distribution of components. In this paper, we describe a new approach for dynamic reconfiguration of middleware-based applications that is more transparent for the application developer than existing approaches. We compare our approach with other approaches, and describe a prototype that implements our approach for CORBA-based applications

Probable Person-to-Person Transmission of Legionnaires’ Disease

Correspondence to the Editor.Legionnaires’ disease is an often severe form of pneumonia that is typically acquired by susceptible persons (e.g., elderly persons and smokers) through inhalation of aerosols that contain legionella species.1-4 A cluster of cases of this disease occurred in Vila Franca de Xira, Portugal, in 2014