A systematic analysis of metadata application profiles of learning object repositories in Europe

© Springer-Verlag Berlin Heidelberg 2014. Over the past years, several initiatives have emerged worldwide towards the provision of open access to educational resources, in the form of learning objects (LOs). The main objective of such initiatives is to support the process of organizing, classifying, and storing LOs and their associated metadata in Web-based repositories which are called learning object repositories (LORs). Within this framework, popular ways for describing LOs are the Dublin Core Metadata Element Set (DCMES) and the IEEE Learning Object Metadata (LOM) Standard. However, it has been recognized that it is not possible for generic standards such as DCMES and IEEE LOM to be used to fully meet community and context-specific users’ needs. This has lead to the emergence of the metadata application profile (AP) concept and a number of metadata APs have been developed, which are used by a variety of LORs that are currently operating online. On the other hand, with many LORs implemented based on different metadata APs, the issue of metadata interoperability between these LORs is crucial. In this chapter, we focus on metadata interoperability of different LORs that have been developed by institutions, communities, or consortiums in Europe. More specifically, we present the results of a systematic analysis of metadata APs used in nineteen (19) European LORs, and we provide recommendations for future development of metadata APs

Studying Tag Vocabulary Behaviour of Social Tagging Systems in Learing Object Repositories

In the field of Technology-enhanced Learning (TeL), social tagging has been applied to Learning Object Repositories (LORs) mainly as a means:(a) to offer an alternative way of classifying the Learning Objects (LOs) based on the tag vocabulary created by the end-users of the LOs, and (b) to facilitate the enhancement of LOs’ descriptions via collaborative tagging. However, in order to be able to understand how a social tagging system performs and whether it can deliver the aforementioned goals, it is important to be able to investigate the evolution of the tag vocabulary, which constitutes the core component of a social tagging system. Within this context, research has focused on different facets of social tagging systems such as the growth of the tag vocabulary, the frequency and reuse of tags, as well as the stability of the tag vocabulary but there are only sporadic studies for investigating these issues in the field of LORs. This paper aims to contribute in studying how social tagging systems perform in the context of LORs by investigating the evolution of the tag vocabulary in OpenScienceResources Repository, a science education domain specific repository with a rich dataset operating in Europe for 5 years

Role of Tissue Factor in Mycobacterium tuberculosis-Induced Inflammation and Disease Pathogenesis

Tuberculosis (TB) is a chronic lung infectious disease characterized by severe inflammation and lung granulomatous lesion formation. Clinical manifestations of TB include hypercoagulable states and thrombotic complications. We previously showed that Mycobacterium tuberculosis (M.tb) infection induces tissue factor (TF) expression in macrophages in vitro. TF plays a key role in coagulation and inflammation. In the present study, we investigated the role of TF in M.tb-induced inflammatory responses, mycobacterial growth in the lung and dissemination to other organs. Wild-type C57BL/6 and transgenic mice expressing human TF, either very low levels (low TF) or near to the level of wild-type (HTF), in place of murine TF were infected with M.tb via aerosol exposure. Levels of TF expression, proinflammatory cytokines and thrombin-antithrombin complexes were measured post M.tb infection and mycobacterial burden in the tissue homogenates were evaluated. Our results showed that M.tb infection did not increase the overall TF expression in lungs. However, macrophages in the granulomatous lung lesions in all M.tb-infected mice, including low TF mice, showed increased levels of TF expression. Conspicuous fibrin deposition in the granuloma was detected in wild-type and HTF mice but not in low TF mice. M.tb infection significantly increased expression levels of cytokines IFN-γ, TNF-α, IL-6 and IL-1ß in lung tissues. However, no significant differences were found in proinflammatory cytokines among the three experimental groups. Mycobacterial burden in lungs and dissemination into spleen and liver were essentially similar in all three genotypes. Our data indicate, in contrast to that observed in acute bacterial infections, that TF-mediated coagulation and/or signaling does not appear to contribute to the host-defense in experimental tuberculosis