Evaluation of quality of life in Chilean patients with orthognathic surgery. A cohort study.

Objective: To compare the presurgical and immediate postsurgical quality of life in Chilean patients with orthognathic surgery. Material and Methods: Cohort study. The study included 30 patients (mean age 20.73, 53.33% male) who underwent orthognathic surgery primarily for severe skeletal abnormalities, (17 surgeries, 56.7%) and moderate skeletal abnormalities (12 surgeries, 40%), from three Chilean hospitals between February and June 2016. Patients were asked to answer the World Health Organization quality of life Bref version questionnaire (WHOQOL-BREF) validated in Spanish to measure quality of life (QoL) two weeks before and three months after the surgery. Scores for general QoL and for every domain of QoL were described. Variations in the scores of general QoL were analyzed according to sex and severity of orofacial malformation (mild, moderate or severe) (ttest p <0.05; STATA 10.0). Results: The average score for QoL according to the WHOQOL-BREF scale was 76.43±13.83 before surgery and 90.5±7.18 three months after surgery (p<0.001). Statistically significant differences according to sex and type of orofacial malformation were found (p<0.01). An increase in the score in all the domains of the WHOQOOL-BREF scale was observed. Conclusion: Orthognathic surgery significantly improved QoL scores in Chilean patients according to the WHOQOL-BREF scale

Measurement of the W±ZW^{\pm}Z boson pair-production cross section in pppp collisions at s=13\sqrt{s}=13 TeV with the ATLAS Detector

The production of $W^{\pm}Z$ events in proton--proton collisions at a centre-of-mass energy of 13 TeV is measured with the ATLAS detector at the LHC. The collected data correspond to an integrated luminosity of 3.2 fb$^{-1}$. The $W^{\pm}Z$ candidates are reconstructed using leptonic decays of the gauge bosons into electrons or muons. The measured inclusive cross section in the detector fiducial region for leptonic decay modes is $\sigma_{W^\pm Z \rightarrow \ell^{'} \nu \ell \ell}^{\textrm{fid.}} = 63.2 \pm 3.2$ (stat.) $\pm 2.6$ (sys.) $\pm 1.5$ (lumi.) fb. In comparison, the next-to-leading-order Standard Model prediction is $53.4^{+3.6}_{-2.8}$ fb. The extrapolation of the measurement from the fiducial to the total phase space yields $\sigma_{W^{\pm}Z}^{\textrm{tot.}} = 50.6 \pm 2.6$ (stat.) $\pm 2.0$ (sys.) $\pm 0.9$ (th.) $\pm 1.2$ (lumi.) pb, in agreement with a recent next-to-next-to-leading-order calculation of $48.2^{+1.1}_{-1.0}$ pb. The cross section as a function of jet multiplicity is also measured, together with the charge-dependent $W^+Z$ and $W^-Z$ cross sections and their ratio

Reconstruction of primary vertices at the ATLAS experiment in Run 1 proton-proton collisions at the LHC

This paper presents the method and performance of primary vertex reconstruction in proton-proton collision data recorded by the ATLAS experiment during Run 1 of the LHC. The studies presented focus on data taken during 2012 at a centre-of-mass energy of [Formula: see text] TeV. The performance has been measured as a function of the number of interactions per bunch crossing over a wide range, from one to seventy. The measurement of the position and size of the luminous region and its use as a constraint to improve the primary vertex resolution are discussed. A longitudinal vertex position resolution of about [Formula: see text] is achieved for events with high multiplicity of reconstructed tracks. The transverse position resolution is better than [Formula: see text] and is dominated by the precision on the size of the luminous region. An analytical model is proposed to describe the primary vertex reconstruction efficiency as a function of the number of interactions per bunch crossing and of the longitudinal size of the luminous region. Agreement between the data and the predictions of this model is better than 3% up to seventy interactions per bunch crossing