Substructure of high-p_T Jets at the LHC

We study high-pt jets from QCD and from highly-boosted massive particles such as tops, W, Z and Higgs, and argue that infrared-safe observables can help reduce QCD backgrounds. Jets from QCD are characterized by different patterns of energy flow compared to the products of highly-boosted heavy particle decays, and we employ a variety of jet shapes, observables restricted to energy flow within a jet, to explore this difference. Results from Monte Carlo generators and arguments based on perturbation theory support the discriminating power of the shapes we refer to as planar flow and angularities. We emphasize that for massive jets, these and other observables can be analyzed perturbatively.Comment: 5 pages and 4 figure

A new approach to the "apparent survival" problem: Estimating true survival rates from mark-recapture studies

Survival estimates generated from live capture-mark-recapture studies may be negatively biased due to the permanent emigration of marked individuals from the study area. In the absence of a robust analytical solution, researchers typically sidestep this problem by simply reporting estimates using the term "apparent survival." Here, we present a hierarchical Bayesian multistate model designed to estimate true survival by accounting for predicted rates of permanent emigration. Initially we use dispersal kernels to generate spatial projections of dispersal probability around each capture location. From these projections, we estimate emigration probability for each marked individual and use the resulting values to generate bias-adjusted survival estimates from individual capture histories. When tested using simulated data sets featuring variable detection probabilities, survival rates, and dispersal patterns, the model consistently eliminated negative biases shown by apparent survival estimates from standard models. When applied to a case study concerning juvenile survival in the endangered Cape Sable Seaside Sparrow (Ammodramus maritimus mirabilis), bias-adjusted survival estimates increased more than twofold above apparent survival estimates. Our approach is applicable to any capture-mark-recapture study design and should be particularly valuable for organisms with dispersive juvenile life stages.James J. Gilroy, Thomas Virzi, Rebecca L. Boulton, and Julie L. Lockwoo

Impact of CD14 Polymorphisms on Anti-Apolipoprotein A-1 IgG-Related Coronary Artery Disease Prediction in the General Population.

We aimed to determine whether autoantibodies against apoA-1 (apolipoprotein A-1; anti-apoA-1 IgG) predict incident coronary artery disease (CAD), defined as adjudicated incident myocardial infarction, angina, percutaneous coronary revascularization, or bypass grafting, in the general population. We further investigated whether this association is modulated by a functional CD14 receptor single nucleotide polymorphism. In a prospectively studied, population-based cohort of 5220 subjects (mean age 52.6±10.7 years, 47.4% males), followed over a median period of 5.6 years, subjects positive versus negative for anti-apoA-1 IgG presented a total CAD rate of 3.9% versus 2.8% (P=0.077) and a nonfatal CAD rate of 3.6% versus 2.3% (P=0.018), respectively. After multivariate adjustment for established cardiovascular risk factors, the hazard ratios of anti-apoA-1 IgG for total and nonfatal CAD were: hazard ratio=1.36 (95% confidence interval, 0.94-1.97; P=0.105) and hazard ratio=1.53 (95% confidence interval, 1.03-2.26; P=0.034), respectively. In subjects with available genetic data for the C260T rs2569190 single nucleotide polymorphism in the CD14 receptor gene (n=4247), we observed a significant interaction between anti-apoA-1 IgG and rs2569190 allele status with regards to CAD risk, with anti-apoA-1 IgG conferring the highest risk for total and nonfatal CAD in non-TT carriers, whereas being associated with the lowest risk for total and nonfatal CAD in TT homozygotes (P for interaction =0.011 and P for interaction =0.033, respectively). Anti-apoA-1 IgG are independent predictors of nonfatal incident CAD in the general population. The strength of this association is dependent on a functional polymorphism of the CD14 receptor gene, a finding suggesting a gene-autoantibody interaction for the development of CAD

Association between anti-apolipoprotein A-1 antibodies and cardiovascular disease in the general population. Results from the CoLaus study.

We aimed to determine the association between autoantibodies against apolipoprotein A-1 (anti-apoA-1 IgG) and prevalent cardiovascular (CV) disease (CVD) as well as markers of CV risk in the general population. Cross-sectional data were obtained from 6649 subjects (age 52.6 ± 10.7 years, 47.4 % male) of the population-based CoLaus study. CVD was defined as myocardial infarction, angina pectoris, percutaneous revascularisation or bypass grafting for ischaemic heart disease stroke or transient ischaemic attack, and was assessed according to standardised medical records. Anti-apoA-1 IgG and biological markers were measured by ELISA and conventional automated techniques, respectively. Prevalence of high anti-apoA-1 IgG levels in the general population was 19.9 %. Presence of anti-apoA-1 IgG was significantly associated with CVD [odds ratio 1.34, 95 % confidence interval (1.05-1.70), p=0.018], independently of established CV risk factors (CVRFs) including age, sex, hypertension, smoking, diabetes, low and high-density lipoprotein cholesterol levels. The n=455 (6.8 %) study participants with a history of CVD (secondary prevention subgroup) presented higher median anti-ApoA-1 IgG values compared with subjects without CVD (p=0.029). Among patients in the secondary prevention subgroup, those with positive anti-apoA-1 IgG levels had lower HDL (p=0.002) and magnesium (p=0.001) levels, but increased uric acid and high-sensitivity C-reactive protein levels (p=0.022, and p<0.001, respectively) compared to patients with negative anti-apoA-1 IgG levels. In conclusion, anti-apoA-1 IgG levels are independently associated with CVD in the general population and also related to CV biomarkers in secondary prevention. These findings indicate that anti-apoA-1 IgG may represent a novel CVRF and need further study in prospective cohorts

Prognostic and therapeutic considerations of antibodies against c-ter apolipoprotein A-1 in the general population.

Autoantibodies against apolipoprotein A1 (anti-apoA1 IgGs) and its C-terminal region (cter apoA1) have emerged as an independent biomarker for cardiovascular disease. Cter apoA1 mimetic peptides were shown to reverse the deleterious anti-apoA1 IgG effects in vitro. We evaluated the association of anti-cter apoA1 IgGs with overall mortality in the general population and tested the ability of a cter apoA1 mimetic peptide to reverse the anti-apoA1 IgG-induced inflammatory response and mortality in vitro and in vivo, respectively. Anti-cter apoA1 IgGs were measured in serum samples of 6386 participants of the CoLaus study of which 5220 were followed for a median duration of 5.6 years. The primary outcome was overall mortality. The peptide inhibitory concentration 50% (IC <sub>50</sub> ) was determined in vitro on HEK-Blue-4 and RAW cells. ApoE <sup>-/-</sup> mice were exposed to 16 weeks of anti-apoA1IgG passive immunisation with and without peptide co-incubation. Anti-cter apoA1 IgGs were associated with higher interleukin 6 levels and independently predicted overall mortality; an increase of one standard deviation of anti-cter apoA1 IgG level was associated with an 18% increase in mortality risk (hazard ratio: 1.18, 95% confidence interval: 1.04-1.33; P = 0.009). The cterApoA1 analogue reversed the antibody-mediated inflammatory response with an IC <sub>50</sub> of 1 µm in vitro but did not rescue the significant anti-apoA1 IgG-induced mortality rate in vivo (69% vs. 23%, LogRank P = 0.02). Anti-cter apoA1 IgG independently predicts overall mortality in the general population. Despite being effective in vitro, our cter apoA1 analogue did not reverse the anti-apoA1 IgG-induced mortality in mice. Our data suggest that these autoantibodies are not readily treatable through cognate peptide immunomodulation

Single hadron response measurement and calorimeter jet energy scale uncertainty with the ATLAS detector at the LHC

The uncertainty on the calorimeter energy response to jets of particles is derived for the ATLAS experiment at the Large Hadron Collider (LHC). First, the calorimeter response to single isolated charged hadrons is measured and compared to the Monte Carlo simulation using proton-proton collisions at centre-of-mass energies of sqrt(s) = 900 GeV and 7 TeV collected during 2009 and 2010. Then, using the decay of K_s and Lambda particles, the calorimeter response to specific types of particles (positively and negatively charged pions, protons, and anti-protons) is measured and compared to the Monte Carlo predictions. Finally, the jet energy scale uncertainty is determined by propagating the response uncertainty for single charged and neutral particles to jets. The response uncertainty is 2-5% for central isolated hadrons and 1-3% for the final calorimeter jet energy scale.Comment: 24 pages plus author list (36 pages total), 23 figures, 1 table, submitted to European Physical Journal

Evidence for the h_b(1P) meson in the decay Upsilon(3S) --> pi0 h_b(1P)

Using a sample of 122 million Upsilon(3S) events recorded with the BaBar detector at the PEP-II asymmetric-energy e+e- collider at SLAC, we search for the $h_b(1P)$ spin-singlet partner of the P-wave chi_{bJ}(1P) states in the sequential decay Upsilon(3S) --> pi0 h_b(1P), h_b(1P) --> gamma eta_b(1S). We observe an excess of events above background in the distribution of the recoil mass against the pi0 at mass 9902 +/- 4(stat.) +/- 2(syst.) MeV/c^2. The width of the observed signal is consistent with experimental resolution, and its significance is 3.1sigma, including systematic uncertainties. We obtain the value (4.3 +/- 1.1(stat.) +/- 0.9(syst.)) x 10^{-4} for the product branching fraction BF(Upsilon(3S)-->pi0 h_b) x BF(h_b-->gamma eta_b).Comment: 8 pages, 4 postscript figures, submitted to Phys. Rev. D (Rapid Communications

Standalone vertex finding in the ATLAS muon spectrometer

A dedicated reconstruction algorithm to find decay vertices in the ATLAS muon spectrometer is presented. The algorithm searches the region just upstream of or inside the muon spectrometer volume for multi-particle vertices that originate from the decay of particles with long decay paths. The performance of the algorithm is evaluated using both a sample of simulated Higgs boson events, in which the Higgs boson decays to long-lived neutral particles that in turn decay to bbar b final states, and pp collision data at √s = 7 TeV collected with the ATLAS detector at the LHC during 2011

Measurements of Higgs boson production and couplings in diboson final states with the ATLAS detector at the LHC

Measurements are presented of production properties and couplings of the recently discovered Higgs boson using the decays into boson pairs, H →γ γ, H → Z Z∗ →4l and H →W W∗ →lνlν. The results are based on the complete pp collision data sample recorded by the ATLAS experiment at the CERN Large Hadron Collider at centre-of-mass energies of √s = 7 TeV and √s = 8 TeV, corresponding to an integrated luminosity of about 25 fb−1. Evidence for Higgs boson production through vector-boson fusion is reported. Results of combined fits probing Higgs boson couplings to fermions and bosons, as well as anomalous contributions to loop-induced production and decay modes, are presented. All measurements are consistent with expectations for the Standard Model Higgs boson