Contribution structures

The invisibility of the individuals and groups that gave rise to requirements artifacts has been identified as a primary reason for the persistence of requirements traceability problems. This paper presents an approach, based on modelling the dynamic contribution structures underlying requirements artifacts, which addresses this issue. We show how these structures can be defined, using information about the agents who have contributed to artifact production, in conjunction with details of the numerous traceability relations that hold within and between artifacts themselves. We describe a scheme, derived from work in sociolinguistics, which can be used to indicate the capacities in which agents contribute. We then show how this information can be used to infer details about the social roles and commitments of agents with respect to their various contributions and to each other. We further propose a categorisation for artifact-based traceability relations and illustrate how they impinge on the identification and definition of these structures. Finally, we outline how this approach can be implemented and supported by tools, explain the means by which requirements change can be accommodated in the corresponding contribution structures, and demonstrate the potential it provides for "personnel-based" requirements traceability

The Contribution of EU Law to the Regulation of Online Speech

Internet regulation in the European Union (EU) is receiving significant attention and criticism in the United States. The European Court of Justice’s (ECJ) judgment in the case Glawischnig-Piesczek v. Facebook Ireland, in which the ECJ found a take-down order against Facebook for defamatory content with global effect permissible under EU law, was closely scrutinized in the United States. These transsystemic debates are valuable but need to be conducted with a thorough understanding of the relevant legal framework and its internal logic. This note aims to provide the context to properly assess the role the ECJ and EU law play in the regulation of online speech. The note argues that the alleged shortcomings of the Glawischnig- Piesczek case are actually the result of a convincing interpretation of the applicable EU law while respecting the prerogatives of the member states in the areas of speech regulation, jurisdiction, and comity. Most of the issues that commentators wanted the ECJ to decide were beyond its reach in this case. The paper argues that EU law’s contribution in the field of online speech regulation should be regarded as a realization of the dangers of illegal online content, resulting in an effective protection of the interests harmed. This implies the rejection of a “whack-a-mole” approach towards illegal online content in favor of more effective ways to protect against the harm caused by illegal online speech. At the same time, the case highlights the necessity to establish a workable theory of jurisdiction and comity in the digital age

Altered Expression of the CB1 Cannabinoid Receptor in the Triple Transgenic Mouse Model of Alzheimer's Disease

The endocannabinoid system has gained much attention as a new potential pharmacotherapeutic target in various neurodegenerative diseases, including Alzheimer's disease (AD). However, the association between CB1 alterations and the development of AD neuropathology is unclear and often contradictory. In this study, brain CB1 mRNA and CB1 protein levels were analyzed in 3 × Tg-AD mice and compared to wild-type littermates at 2, 6 and 12 months of age, using in-situ hybridization and immunohistochemistry, respectively. Semiquantitative analysis of CB1 expression focused on the prefrontal cortex (PFC), prelimbic cortex, dorsal hippocampus (DH), basolateral amygdala complex (BLA), and ventral hippocampus (VH), all areas with high CB1 densities that are strongly affected by neuropathology in 3 × Tg-AD mice. At 2 months of age, there was no change in CB1 mRNA and protein levels in 3 × Tg-AD mice compared to Non-Tg mice in all brain areas analyzed. However, at 6 and 12 months of age, CB1 mRNA levels were significantly higher in PFC, DH, and BLA, and lower in VH in 3 × Tg-AD mice compared to wild-type littermates. CB1 immunohistochemistry revealed that CB1 protein expression was unchanged in 3 × Tg-AD at 2 and 6 months of age, while a significant decrease in CB1 receptor immunoreactivity was detected in the BLA and DH of 12-month-old 3 × Tg-AD mice, with no sign of alteration in other brain areas. The altered CB1 levels appear, rather, to be age-and/or pathology-dependent, indicating an involvement of the endocannabinoid system in AD pathology and supporting the ECS as a potential novel therapeutic target for treatment of AD

Contribution biplots

In order to interpret the biplot it is necessary to know which points – usually variables – are the ones that are important contributors to the solution, and this information is available separately as part of the biplot’s numerical results. We propose a new scaling of the display, called the contribution biplot, which incorporates this diagnostic directly into the graphical display, showing visually the important contributors and thus facilitating the biplot interpretation and often simplifying the graphical representation considerably. The contribution biplot can be applied to a wide variety of analyses such as correspondence analysis, principal component analysis, log-ratio analysis and the graphical results of a discriminant analysis/MANOVA, in fact to any method based on the singular-value decomposition. In the contribution biplot one set of points, usually the rows of the data matrix, optimally represent the spatial positions of the cases or sample units, according to some distance measure that usually incorporates some form of standardization unless all data are comparable in scale. The other set of points, usually the columns, is represented by vectors that are related to their contributions to the low-dimensional solution. A fringe benefit is that usually only one common scale for row and column points is needed on the principal axes, thus avoiding the problem of enlarging or contracting the scale of one set of points to make the biplot legible. Furthermore, this version of the biplot also solves the problem in correspondence analysis of low-frequency categories that are located on the periphery of the map, giving the false impression that they are important, when they are in fact contributing minimally to the solution.biplot, contributions, correspondence analysis, discriminant analysis, log-ratio analysis, MANOVA, principal component analysis, scaling, singular value decomposition, weighting.

INSDOC’S contribution to bibliometrics

Traces the history of bibliometric research, training and activities in INSDOC. Describes briefly the objectives, facilities, services, research activities, and publications of National Centre on Bibliometrics

Gravitational contribution to fermion masses

In the context of a nonlinear gauge theory of the Poincar\'e group, we show that covariant derivatives of Dirac fields include a coupling to the translational connections, manifesting itself in the matter action as a universal background mass contribution to fermions.Comment: revtex4, 9 pages, no figures, to be published in Eur.Phys.J.C, 200