To be or not to be, the importance of Digital Identity in the networked society

The emergence of the web has had a deep impact at different levels of our society, changing the way people connect, interact, share information, learn and work. In the current knowledge economy, participatory media seems to play an important part in everyday interactions. The term “digital identity” is becoming part of both our lexicon and our lives. This paper explores some of the aspect s regarding approaches and practices of educators, using web technologies to foster their digital identity within their networks and, at the same time, developing a social presence to complement their professional and academic profiles. In fact, we think it is imperative to discuss the relationship between our social presence and our professional life, as online the two are often intertwined. We present the issues the web poses through dichotomies: open or closed, genuine or fake, single or multiple. We also comment on different approaches to these dichotomies through examples extracted from recent projects, drawing from user’s experiences in building their digital identities. This paper looks at the importance of digital identity in the current networked society, by reviewing the contemporaneous scenario of the participatory web, raising a set of questions about the advantages and implication of consciously developing one’s digital identity, thus opening the discussion regarding openness, uniqueness and integrity in connection with one’s digital identity. This paper is also a reflection of thinking and practice in progress, drawing from examples and real-life situations observed in a diversity of projects. The issue could be reduced, perhaps, to whether one consciously becomes a part of the digital world or not, and how that participation is managed. It is up to us to manage it wisely, and guide knowledge workers in their journey to create theirs

CONVERSION to ORGANIC FARMING in MAINLAND PORTUGAL

The objectives of the research were: i) to assess the in-conversion period as a barrier impeding farms conversion to organic; ii) to assess the potential of conversion-grade markets in removing this barrier; iii) to identify other barriers (drives) along the food chain impeding (easing) farms conversion in mainland Portugal. Results show that the in-conversion period is not the major barrier to conversion nor is a good idea the set-up of conversion grade markets to help Portuguese farms’ conversion. Conversion feasibility depends of the organic market premium prices, in intensive farms, and of the CAP organic agri-environmental area payments, in extensive farms.organic farming, conversion, conversion grade markets, market premium prices, CAP payments.

Natural Gauge and Gravitational Coupling Unification and the Superpartner Masses

The possibility to achieve unification at the string scale in the context of the simplest supersymmetric grand unified theory is investigated. We find conservative upper bounds on the superpartner masses consistent with the unification of gauge and gravitational couplings, M_{\tilde G} < 5 TeV and M_{\tilde f} < 3 \times 10^7 GeV, for the superparticles with spin one-half and zero, respectively. These bounds hint towards the possibility that this supersymmetric scenario could be tested at future colliders, and in particular, at the forthcoming LHC.Comment: 8 pages, 4 figures, version accepted in Physics Letters

Anomaly-free U(1) gauge symmetries in neutrino seesaw flavor models

Adding right-handed neutrino singlets and/or fermion triplets to the particle content of the Standard Model allows for the implementation of the seesaw mechanism to give mass to neutrinos and, simultaneously, for the construction of anomaly-free gauge group extensions of the theory. We consider Abelian extensions based on an extra U(1)_X gauge symmetry, where X is an arbitrary linear combination of the baryon number B and the individual lepton numbers L_{e,mu,tau}. By requiring cancellation of gauge anomalies, we perform a detailed analysis in order to identify the charge assignments under the new gauge symmetry that lead to neutrino phenomenology compatible with current experiments. In particular, we study how the new symmetry can constrain the flavor structure of the Majorana neutrino mass matrix, leading to two-zero textures with a minimal extra fermion and scalar content. The possibility of distinguishing different gauge symmetries and seesaw realizations at colliders is also briefly discussed.Comment: 12 pages, 2 figures, 7 tables; comments and references added, a new subsection with nonstandard interactions of neutrinos included; final version to appear in Phys. Rev.

Threads and Or-Parallelism Unified

One of the main advantages of Logic Programming (LP) is that it provides an excellent framework for the parallel execution of programs. In this work we investigate novel techniques to efficiently exploit parallelism from real-world applications in low cost multi-core architectures. To achieve these goals, we revive and redesign the YapOr system to exploit or-parallelism based on a multi-threaded implementation. Our new approach takes full advantage of the state-of-the-art fast and optimized YAP Prolog engine and shares the underlying execution environment, scheduler and most of the data structures used to support YapOr's model. Initial experiments with our new approach consistently achieve almost linear speedups for most of the applications, proving itself as a good alternative for exploiting implicit parallelism in the currently available low cost multi-core architectures.Comment: 17 pages, 21 figures, International Conference on Logic Programming (ICLP 2010