Autonomous University of Barcelona

About: Autonomous University of Barcelona is a education organization based out in Cerdanyola del Vallès, Spain. It is known for research contribution in the topics: Population & Context (language use). The organization has 37833 authors who have published 80514 publications receiving 2321142 citations. The organization is also known as: Universitat Autònoma de Barcelona & Computer Vision Center.

The homotopy theory of fusion systems

Abstract: The main goal of this paper is to identify and study a certain class of spaces which in many ways behave like p-completed classifying spaces of finite groups These spaces occur as the “classifying spaces” of certain algebraic objects, which we call p-local finite groups A p-local finite group consists, roughly speaking, of a finite p-group S and fusion data on subgroups of S, encoded in a way explained below Our starting point is our earlier paper [BLO] on p-completed classifying spaces of finite groups, together with the axiomatic treatment by Lluis Puig [Pu], [Pu2] of systems of fusion among subgroups of a given p-group The p-completion of a space X is a space Xp which isolates the properties of X at the prime p, and more precisely the properties which determine its mod p cohomology For example, a map of spaces X f −−→ Y induces a homotopy equivalence Xp ' −−→ Y p if and only if f induces an isomorphism in mod p cohomology; and H(Xp ;Fp) ∼= H∗(X ;Fp) in favorable cases (if X is “p-good”) When G is a finite group, the p-completion BGp of its classifying space encodes many of the properties of G at p For example, not only the mod p cohomology of BG, but also the Sylow p-subgroup of G together with all fusion among its subgroups, are determined up to isomorphism by the homotopy type of BGp Our goal here is to give a direct link between p-local structures and homotopy types which arise from them This theory tries to make explicit the essence of what it means to be the p-completed classifying space of a finite group, and at the same time yields new spaces which are not of this type, but which still enjoy most of the properties a space of the form BGp would have We hope that the ideas presented here will have further applications and generalizations in algebraic topology But this theory also fits well with certain aspects of modular representation theory In particular, it may give a way of constructing classifying spaces for blocks in the group ring of a finite group over an algebraically closed field of characteristic p A saturated fusion system F over a p-group S consists of a set HomF (P,Q) of monomorphisms, for each pair of subgroups P,Q ≤ S, which form a category under composition, include all monomorphisms induced by conjugation in S, and satisfy certain other axioms formulated by Puig (Definitions 11 and 12 below) In particular, these axioms are satisfied by the conjugacy homomorphisms in a finite group We refer to [Pu] and [Pu2] for more details of Puig’s work on saturated

Ion-sensitive field-effect transistors fabricated in a commercial cmos technology

Abstract: The fabrication of pH-sensitive ISFET devices in an unmodified two-metal commercial CMOS technology (1.0 m from Atmel-ES2) is reported. The ISFET devices have a gate structure compatible with the CMOS process, with an electrically floating electrode consisting on polysilicon plus the two metals. The passivation oxynitride layer acts as the pH-sensitive material in contact with the liquid solution. The devices have shown good operating characteristics, with a 47 mV/pH response. The use of a commercial CMOS process allows the straightforward integration of signal-processing circuitry. An ISFET amplifier circuit has been integrated with the ISFET sensors.

Hormone therapy for preventing cardiovascular disease in post‐menopausal women

Abstract: Background Evidence from systematic reviews of observational studies suggests that hormone therapy may have beneficial effects in reducing the incidence of cardiovascular disease events in post-menopausal women, however the results of randomised controlled trials (RCTs) have had mixed results. This is an updated version of a Cochrane review published in 2013. Objectives To assess the effects of hormone therapy for the prevention of cardiovascular disease in post-menopausal women, and whether there are differential effects between use in primary or secondary prevention. Secondary aims were to undertake exploratory analyses to (i) assess the impact of time since menopause that treatment was commenced (≥ 10 years versus < 10 years), and where these data were not available, use age of trial participants at baseline as a proxy (≥ 60 years of age versus < 60 years of age); and (ii) assess the effects of length of time on treatment. Search methods We searched the following databases on 25 February 2014: Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE and LILACS. We also searched research and trials registers, and conducted reference checking of relevant studies and related systematic reviews to identify additional studies. Selection criteria RCTs of women comparing orally administered hormone therapy with placebo or a no treatment control, with a minimum of six months follow-up. Data collection and analysis Two authors independently assessed study quality and extracted data. We calculated risk ratios (RRs) with 95% confidence intervals (CIs) for each outcome. We combined results using random effects meta-analyses, and undertook further analyses to assess the effects of treatment as primary or secondary prevention, and whether treatment was commenced more than or less than 10 years after menopause. Main results We identified six new trials through this update. Therefore the review includes 19 trials with a total of 40,410 post-menopausal women. On the whole, study quality was good and generally at low risk of bias; the findings are dominated by the three largest trials. We found high quality evidence that hormone therapy in both primary and secondary prevention conferred no protective effects for all-cause mortality, cardiovascular death, non-fatal myocardial infarction, angina, or revascularisation. However, there was an increased risk of stroke in those in the hormone therapy arm for combined primary and secondary prevention (RR 1.24, 95% CI 1.10 to 1.41). Venous thromboembolic events were increased (RR 1.92, 95% CI 1.36 to 2.69), as were pulmonary emboli (RR 1.81, 95% CI 1.32 to 2.48) on hormone therapy relative to placebo. The absolute risk increase for stroke was 6 per 1000 women (number needed to treat for an additional harmful outcome (NNTH) = 165; mean length of follow-up: 4.21 years (range: 2.0 to 7.1)); for venous thromboembolism 8 per 1000 women (NNTH = 118; mean length of follow-up: 5.95 years (range: 1.0 to 7.1)); and for pulmonary embolism 4 per 1000 (NNTH = 242; mean length of follow-up: 3.13 years (range: 1.0 to 7.1)). We performed subgroup analyses according to when treatment was started in relation to the menopause. Those who started hormone therapy less than 10 years after the menopause had lower mortality (RR 0.70, 95% CI 0.52 to 0.95, moderate quality evidence) and coronary heart disease (composite of death from cardiovascular causes and non-fatal myocardial infarction) (RR 0.52, 95% CI 0.29 to 0.96; moderate quality evidence), though they were still at increased risk of venous thromboembolism (RR 1.74, 95% CI 1.11 to 2.73, high quality evidence) compared to placebo or no treatment. There was no strong evidence of effect on risk of stroke in this group. In those who started treatment more than 10 years after the menopause there was high quality evidence that it had little effect on death or coronary heart disease between groups but there was an increased risk of stroke (RR 1.21, 95% CI 1.06 to 1.38, high quality evidence) and venous thromboembolism (RR 1.96, 95% CI 1.37 to 2.80, high quality evidence). Authors' conclusions Our review findings provide strong evidence that treatment with hormone therapy in post-menopausal women overall, for either primary or secondary prevention of cardiovascular disease events has little if any benefit and causes an increase in the risk of stroke and venous thromboembolic events.

Models of non-relativistic quantum gravity: The Good, the bad and the healthy

Abstract: Hořava’s proposal for non-relativistic quantum gravity introduces a preferred time foliation of space-time which violates the local Lorentz invariance. The foliation is encoded in a dynamical scalar field which we call ‘khronon’. The dynamics of the khronon field is sensitive to the symmetries and other details of the particular implementations of the proposal. In this paper we examine several consistency issues present in three non-relativistic gravity theories: Hořava’s projectable theory, the healthy non-projectable extension, and a new extension related to ghost condensation. We find that the only model which is free from instabilities and strong coupling is the non-projectable one. We elaborate on the phenomenology of the latter model including a discussion of the couplings of the khronon to matter. In particular, we obtain the parameters of the post-Newtonian expansion in this model and show that they are compatible with current observations.