Glacial Isostatic Adjustment of the British Isles: New constraints form GPS measurements of crustal motion

in Geophysical Journal International (2009), 178(178), 14-22

We compared estimates of crustal velocities within Great Britain based on continuous global positioning system (CGPS) measurements to predictions from a model of glacial isostatic adjustment (GIA). The ... [more ▼]

We compared estimates of crustal velocities within Great Britain based on continuous global positioning system (CGPS) measurements to predictions from a model of glacial isostatic adjustment (GIA). The observed and predicted values for vertical motion are highly correlated indicating that GIA is the dominant geodynamic process contributing to this field. In contrast, motion of the Eurasian plate dominates the horizontal motion component. A model of plate motion was adopted to remove this signal in order to estimate intraplate horizontal motion associated with GIA. However, a coherent pattern of horizontal motion was not evident in the resulting velocity field. We adopted a recently published model of the British–Irish ice sheet to predict vertical crustal motion for a large number of spherically symmetric Earth viscosity models. Our results show that the adopted ice model is capable of producing a high-quality fit to the observations. The CGPS-derived estimates of vertical motion provide a useful constraint on the average value of viscosity within the upper mantle. Values of model lithospheric thickness and lower mantle viscosity are less well resolved, however. A suite of predictions based on an alternative ice model indicates that the vertical motion data are relatively insensitive to uncertainties in the ice loading history and so the constraints on upper mantle viscosity are robust. [less ▲]

User-Centered Activity Management System for Elderly People

in International Conference on Pervasive Computing Technologies for Healthcare (2009)

Abstract — This paper presents the preliminary results of a multi-disciplinary project aiming at studying technology supported life in a retirement home. The results of semistructured interviews conducted ... [more ▼]

Abstract — This paper presents the preliminary results of a multi-disciplinary project aiming at studying technology supported life in a retirement home. The results of semistructured interviews conducted with a group of 40 (semi-) autonomously living elderly persons are presented. In general they point in the direction of a “differential indication” of technologies in the sense of identifying personal solution for individual needs. Second, results show that the crucial dimension underlying the acceptance of technologies is the notion of personal control. The paper also identifies ten key design factors to build successful applications for elderly people. Finally an initial version of a new system mixing RFID, tactile screen and large display is described. [less ▲]

Asymptotics for posterior hazards

in Annals of Statistics (2009), 37(4), 1906--1945

Stein's method on Wiener chaos

in Probab. Theory Related Fields (2009), 145(1-2), 75--118

Noncentral convergence of multiple integrals

in Annals of Probability (2009), 37(4), 1412--1426

Struggling with the languages of the 'legitimate market' and the 'islets of liberty' (Bourdieu). A case study of pupils with immigrational background in the trilingual school-system of Luxembourg

in International Journal of Multilingualism (2009), 6(1), 68-84

Two Portuguese children of immigrants were observed over a period of two years within the complex sociolinguistic context of the Luxembourgish multilingual school-system. The data allow the analysis of ... [more ▼]

Two Portuguese children of immigrants were observed over a period of two years within the complex sociolinguistic context of the Luxembourgish multilingual school-system. The data allow the analysis of their relations with the languages they learn at school: Luxembourgish, German, French and Portuguese. The observations focus on the two pupils struggling with the languages of the ‘legitimate market’ and the ‘islets of liberty’ (Bourdieu). Their different strategies lead to opposite results: one manages to cope with the system, the other borders on failure. The theoretical frame of the study is based on socio-cultural theory (Vygotsky, 1962), enhanced by the demands of a multilingual school. The study relies on a qualitative, ethnographically oriented methodology. [less ▲]

STIM1 but not STIM2 is an essential regulator of Ca2+ influx-mediated NADPH oxidase activity in neutrophil-like HL-60 cells

in Biochemical Pharmacology (2009), 78(5), 504-513

Extracellular Ca2+ entry, primarily mediated through store-operated Ca2+ entry (SOCE), is known to be a critical event for NADPH oxidase (NOX2) regulation in neutrophils. While defective NOX2 activity has ... [more ▼]

Extracellular Ca2+ entry, primarily mediated through store-operated Ca2+ entry (SOCE), is known to be a critical event for NADPH oxidase (NOX2) regulation in neutrophils. While defective NOX2 activity has been linked to various inflammatory diseases, regulatory mechanisms that control Ca2+ influx-induced NOX2 activation are poorly understood in SOCE. The role of STIM1, a Ca2+ sensor that transduces the store depletion signal to the plasma membrane, seems well established and supported by numerous studies in non-phagocytic cells. Here, in neutrophil-like HL-60 cells we used a siRNA approach to delineate the effect of STIM1 knock-down on NOX2 activity regulated by Ca2+ influx. Because the function of the STIM1 homolog, STIM2, is still unclear, we determined the consequence of STIM2 knock-down on Ca2+ and NOX2. STIM1 and STIM2 knock-down was effective and isoform specific when assayed by real-time PCR and Western blotting. Consistent with a unique role of STIM1 in the regulation of SOCE, STIM1, but not STIM2, siRNA significantly decreased Ca2+ influx induced by fMLF or the SERCA pump inhibitor thapsigargin. A redistribution of STIM1, originally localized intracellularly, near the plasma membrane was observed by confocal microscopy upon stimulation by fMLF. Inhibition of STIM1-induced SOCE led to a marked decrease in NOX2 activity while STIM2 siRNA had no effect. Thus, our results provide evidence for a role of STIM1 protein in the control of Ca2+ influx in neutrophils excluding a STIM2 involvement in this process. It also places STIM1 as a key modulator of NOX2 activity with a potential interest for anti-inflammatory pharmacological development. [less ▲]

What is the public role of the university? A proposal for a public research agenda.

in European Educational Research Journal (2009), 8(2), 250-255

Strongly homotopy Leibniz algebras

Scientific Conference (2009)

Modal Logics of Reactive Frames

in Studia Logica (2009)

A reactive graph generalizes the concept of a graph by making it dynamic, in the sense that the arrows coming out from a point depend on how we got there. This idea was fi rst applied to Kripke semantics ... [more ▼]

A reactive graph generalizes the concept of a graph by making it dynamic, in the sense that the arrows coming out from a point depend on how we got there. This idea was fi rst applied to Kripke semantics of modal logic in [2]. In this paper we strengthen that unimodal language by adding a second operator. One op- erator corresponds to the dynamics relation and the other one relates paths with the same endpoint. We explore the expressivity of this interpretation by axiomatizing some natural subclasses of reactive frames. The main objective of this paper is to present a methodology to study reactive logics using the existent classic techniques. [less ▲]