Aspirin for evidence-based preeclampsia prevention trial: effect of aspirin in prevention of preterm preeclampsia in subgroups of women according to their characteristics and medical and obstetrical history.

Objective: To examine whether there are differences in the effect of aspirin on the incidence of preterm-PE in the ASPRE trial in subgroups defined according to maternal characteristics and medical and obstetrical history. Study design: This was a secondary analysis of data from the ASPRE trial. In ASPRE women with singleton pregnancies had screening by means of an algorithm that combines maternal factors and biomarkers at 11-13 weeks’ gestation. Those with an estimated risk for preterm-PE of >1 in 100 were invited to participate in a double-blind trial of aspirin (150 mg/day) vs. placebo from 11 to 14 until 36 weeks’ gestation. Aspirin was associated with a significant reduction in the incidence of preterm-PE with delivery at 90% of the prescribed medication. Results are presented as forest plot with P values for the interaction effects, group sizes, event counts and estimated odds ratios. We examined whether the test of interaction was significant at the 5% level with a Bonferroni adjustment for multiple comparisons. Results: There was no evidence of heterogeneity in the aspirin effect in subgroups defined according to maternal characteristics and obstetrical history. In participants with chronic hypertension preterm-PE occurred in 10.2% (5/49) in the aspirin group and in 8.2% (5/61) in the placebo group (adjusted odds ratio 1.29, 95% confidence interval, 0.33 to 5.12); the respective values in those without chronic hypertension were 1.1% (8/749) in the aspirin group and 3.9% (30/761) in the placebo group (adjusted odds ratio 0.27, 95% confidence interval, 0.12 to 0.60). In all participants with adherence of >90% the adjusted odds ratio in the aspirin group was 0.24 (95% CI 0.09 to 0.65), in the subgroup with chronic hypertension it was 2.06 (95% CI 0.40 to 10.71) and in those without chronic hypertension it was 0.05 (95% CI 0.01 to 0.41). For the complete data set the test of interaction was not significant at the 5% level (p=0.055), but in those with adherence >90%, after adjustment for multiple comparisons, the interaction was significant at the 5% level (p=0.0019). Conclusions: The beneficial effect of aspirin in the prevention of preterm preeclampsia may not apply in pregnancies with chronic hypertension. There was no evidence of heterogeneity in the aspirin effect in subgroups defined according to maternal characteristics and obstetrical history

VAMOS: a Pathfinder for the HAWC Gamma-Ray Observatory

VAMOS was a prototype detector built in 2011 at an altitude of 4100m a.s.l. in the state of Puebla, Mexico. The aim of VAMOS was to finalize the design, construction techniques and data acquisition system of the HAWC observatory. HAWC is an air-shower array currently under construction at the same site of VAMOS with the purpose to study the TeV sky. The VAMOS setup included six water Cherenkov detectors and two different data acquisition systems. It was in operation between October 2011 and May 2012 with an average live time of 30%. Besides the scientific verification purposes, the eight months of data were used to obtain the results presented in this paper: the detector response to the Forbush decrease of March 2012, and the analysis of possible emission, at energies above 30 GeV, for long gamma-ray bursts GRB111016B and GRB120328B.Comment: Accepted for pubblication in Astroparticle Physics Journal (20 pages, 10 figures). Corresponding authors: A.Marinelli and D.Zaboro

Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV

The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8  TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum