198 research outputs found
Observation of the Ankle and Evidence for a High-Energy Break in the Cosmic Ray Spectrum
We have measured the cosmic ray spectrum at energies above eV using
the two air fluorescence detectors of the High Resolution Fly's Eye experiment
operating in monocular mode. We describe the detector, PMT and atmospheric
calibrations, and the analysis techniques for the two detectors. We fit the
spectrum to models describing galactic and extragalactic sources. Our measured
spectrum gives an observation of a feature known as the ``ankle'' near eV, and strong evidence for a suppression near eV.Comment: 14 pages, 9 figures. To appear in Physics Letters B. Accepted versio
A type 2 diabetes subtype responsive to ACCORD intensive glycemia treatment
OBJECTIVE Current type 2 diabetes (T2D) management contraindicates intensive glycemia treatment in patients with high cardiovascular disease (CVD) risk and is partially motivated by evidence of harms in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial. Heterogeneity in response to intensive glycemia treatment has been observed, suggesting potential benefit for some individuals. RESEARCH DESIGN AND METHODS ACCORD was a randomized controlled trial that investigated whether intensively treating glycemia in individuals with T2D would reduce CVD outcomes. Using a novel approach to cluster HbA1c trajectories, we identified groups in the intensive glycemia arm with modified CVD risk. Genome-wide analysis and polygenic score (PS) were developed to predict group membership. Mendelian randomization was performed to infer causality. RESULTS We identified four clinical groupings in the intensive glycemia arm, and clinical group 4 (C4) displayed fewer CVD (hazard ratio [HR] 0.34; P 5 2.01 × 10-3) and microvascular outcomes (HR 0.86; P 5 0.015) than those receiving standard treatment. A singlenucleotide polymorphism, rs220721, in MAS1 reached suggestive significance in C4 (P 5 4.343 10-7). PS predicted C4 with high accuracy (area under the receiver operating characteristic curve 0.98), and this predicted C4 displayed reduced CVD risk with intensive versus standard glycemia treatment (HR 0.53; P 5 4.02 × 10-6), but not reduced risk of microvascular outcomes (P < 0.05). Mendelian randomization indicated causality between PS, on-trial HbA1c, and reduction in CVD outcomes (P < 0.05). CONCLUSIONS We found evidence of a T2D clinical group in ACCORD that benefited from intensive glycemia treatment, and membership in this group could be predicted using genetic variants. This study generates new hypotheses with implications for precision medicine in T2D and represents an important development in this landmark clinical trial warranting further investigation
Feasibility and acceptability of Indigenous Counselling and Nicotine (ICAN) QUIT in Pregnancy multicomponent implementation intervention and study design for Australian Indigenous pregnant women: a pilot cluster randomised step-wedge trial
BACKGROUND: Many health providers (HPs) lack knowledge, confidence, optimism and skills in addressing smoking with pregnant women. This study aimed to explore the feasibility and acceptability of a) a co-designed multi-component intervention for HPs at Aboriginal Medical Services (AMSs) in culturally-targeted pregnancy-specific smoking cessation care and b) the study design. METHODS: Using a randomised step-wedge cluster design, the Indigenous Counselling And Nicotine (ICAN) QUIT in Pregnancy Trial was evaluated across six AMSs in three Australian states. HPs were provided educational resource packages including live interactive webinars, treatment manuals, patient resources, carbon monoxide (CO) meters, and oral Nicotine Replacement Therapy (NRT). Feasibility was assessed through recruitment and retention rates of both pregnant women (12-weeks) and HPs (end of study) as well as the potential to improve women's quit rates. Qualitative interviews with staff post-trial explored acceptability of the intervention and study, based on capability, opportunity and motivation from the Behaviour Change Wheel. RESULTS: Pregnant women (n = 22; 47% (95% CI: 32%, 63%) eligible) and HPs (n = 50; 54% (95% CI: 44%, 64%) eligible) were recruited over 6 months with retention rates of 77% (95% CI: 57%, 90%) and 40% (95% CI: 28%, 54%) respectively. Self-reported 12-week 7-day point-prevalence abstinence was 13.6% (n = 3) and validated abstinent with CO readings ≤6 ppm. Staff interviewed regarding intervention implementation highlighted the importance of provision and use of resources, including training materials, patient resources, CO meters and oral NRT. Resources helped increase capability and opportunity, restructure the environment, and provided social comparison and modelling. Staff were motivated by greater engagement with pregnant women and seeing the women's reductions in CO readings. Having the intervention at the AMSs improved organisational capacity to engage with pregnant women. Staff reported changes to their routine practice that were potentially sustainable. Recommendations for improvement to the implementation of the intervention and research included reducing training length and the tasks related to conducting the study. CONCLUSION: ICAN QUIT in Pregnancy was a pilot study with the ability to enrol Indigenous women. It was feasible to implement and acceptable to most staff of the AMSs in three states, with modifications recommended. Smoking in pregnancy is a key challenge for Indigenous health. The intervention needs to be evaluated through a methodologically rigorous fully-powered study to determine the efficacy of outcomes for women. TRIAL REGISTRATION:Australian and New Zealand Clinical Trials Registry, ACTRN12616001603404. Registered 21 November 2016 - retrospectively registered, https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=371778.Gillian S.Gould, Michelle Bovill, Lauren Pollock, Billie Bonevski, Maree Gruppetta, Lou Atkins, Kristin Carson-Chahhoud, Katherine M.Boydell, Gabrielle R.Gribbin, Chris Oldmeadow, Alix Hall, I CAN QUIT in Pregnancy Pilot Group, Yael Bar-Zeev (Gillian S Gould ... Kristin Carson ... et al.
Measurement of the photon-jet production differential cross section in collisions at \sqrt{s}=1.96~\TeV
We present measurements of the differential cross section dsigma/dpT_gamma
for the inclusive production of a photon in association with a b-quark jet for
photons with rapidities |y_gamma|< 1.0 and 30<pT_gamma <300 GeV, as well as for
photons with 1.5<|y_gamma|< 2.5 and 30< pT_gamma <200 GeV, where pT_gamma is
the photon transverse momentum. The b-quark jets are required to have pT>15 GeV
and rapidity |y_jet| < 1.5. The results are based on data corresponding to an
integrated luminosity of 8.7 fb^-1, recorded with the D0 detector at the
Fermilab Tevatron Collider at sqrt(s)=1.96 TeV. The measured cross
sections are compared with next-to-leading order perturbative QCD calculations
using different sets of parton distribution functions as well as to predictions
based on the kT-factorization QCD approach, and those from the Sherpa and
Pythia Monte Carlo event generators.Comment: 10 pages, 9 figures, submitted to Phys. Lett.
Limits on anomalous trilinear gauge boson couplings from WW, WZ and Wgamma production in pp-bar collisions at sqrt{s}=1.96 TeV
We present final searches of the anomalous gammaWW and ZWW trilinear gauge
boson couplings from WW and WZ production using lepton plus dijet final states
and a combination with results from Wgamma, WW, and WZ production with leptonic
final states. The analyzed data correspond to up to 8.6/fb of integrated
luminosity collected by the D0 detector in pp-bar collisions at sqrt{s}=1.96
TeV. We set the most stringent limits at a hadron collider to date assuming two
different relations between the anomalous coupling parameters
Delta\kappa_\gamma, lambda, and Delta g_1^Z for a cutoff energy scale Lambda=2
TeV. The combined 68% C.L. limits are -0.057<Delta\kappa_\gamma<0.154,
-0.015<lambda<0.028, and -0.008<Delta g_1^Z<0.054 for the LEP parameterization,
and -0.007<Delta\kappa<0.081 and -0.017<lambda<0.028 for the equal couplings
parameterization. We also present the most stringent limits of the W boson
magnetic dipole and electric quadrupole moments.Comment: 10 pages, 5 figures, submitted to PL
Search for pair production of the scalar top quark in muon+tau final states
We present a search for the pair production of scalar top quarks
(), the lightest supersymmetric partners of the top quarks, in
collisions at a center-of-mass energy of 1.96 TeV, using data
corresponding to an integrated luminosity of {7.3 } collected with the
\dzero experiment at the Fermilab Tevatron Collider. Each scalar top quark is
assumed to decay into a quark, a charged lepton, and a scalar neutrino
(). We investigate final states arising from and
. With no significant excess of events observed above the
background expected from the standard model, we set exclusion limits on this
production process in the (,) plane.Comment: Submitted to Phys. Lett.
Search for Higgs bosons of the minimal supersymmetric standard model in p-pbar collisions at sqrt(s)=1.96 TeV
We report results from searches for neutral Higgs bosons produced in p-pbar
collisions recorded by the Dzero experiment at the Fermilab Tevatron Collider.
We study the production of inclusive neutral Higgs boson in the tautau final
state and in association with a b quark in the btautau and bbb final states.
These results are combined to improve the sensitivity to the production of
neutral Higgs bosons in the context of the minimal supersymmetric standard
model (MSSM). The data are found to be consistent with expectation from
background processes. Upper limits on MSSM Higgs boson production are set for
Higgs boson masses ranging from 90 to 300 GeV. We exclude tanBeta>20-30 for
Higgs boson masses below 180 GeV. These are the most stringent constraints on
MSSM Higgs boson production in p-pbar collisions.Comment: Submitted to Phys. Lett.
Quantum Rotation of HCN and DCN in Helium-4
We present calculations of rotational absorption spectra of the molecules HCN
and DCN in superfluid helium-4, using a combination of the Diffusion Monte
Carlo method for ground state properties and an analytic many-body method
(Correlated Basis Function theory) for the excited states. Our results agree
with the experimentally determined effective moment of inertia which has been
obtained from the spectral transition. The correlated basis function
analysis shows that, unlike heavy rotors such as OCS, the J=2 and higher
rotational excitations of HCN and DCN have high enough energy to strongly
couple to rotons, leading to large shifts of the lines and accordingly to
anomalous large spectroscopic distortion constants, to the emergence of
roton-maxon bands, and to secondary peaks in the absorption spectra for J=2 and
J=3.Comment: accepted by Phys. Rev. B; changes: included referee suggestions,
removed typos, added 10 ref
Measurement of the forward-backward asymmetry in Λ0b and Λ¯0b baryon production in pp¯ collisions at s√=1.96 TeV
We measure the forward-backward asymmetry in the production of Λ0b and Λ¯0b baryons as a function of rapidity in pp¯ collisions at s√=1.96 TeV using 10.4 fb−1 of data collected with the D0 detector at the Fermilab Tevatron collider. The asymmetry is determined by the preference of Λ0b or Λ¯0b particles to be produced in the direction of the beam protons or antiprotons, respectively. The measured asymmetry integrated over rapidity y in the range 0.1<|y|<2.0 is A=0.04±0.07(stat)±0.02(syst)
Measurement of angular correlations of jets at sqrt(s)=1.96 TeV and determination of the strong coupling at high momentum transfers
We present a measurement of the average value of a new observable at hadron
colliders that is sensitive to QCD dynamics and to the strong coupling
constant, while being only weakly sensitive to parton distribution functions.
The observable measures the angular correlations of jets and is defined as the
number of neighboring jets above a given transverse momentum threshold which
accompany a given jet within a given distance Delta-R in the plane of rapidity
and azimuthal angle. The ensemble average over all jets in an inclusive jet
sample is measured and the results are presented as a function of transverse
momentum of the inclusive jets, in different regions of Delta-R and for
different transverse momentum requirements for the neighboring jets. The
measurement is based on a data set corresponding to an integrated luminosity of
0.7 fb-1 collected with the D0 detector at the Fermilab Tevatron Collider in
pp-bar collisions at sqrt(s)=1.96 The results are well described by a
perturbative QCD calculation in next-to-leading order in the strong coupling
constant, corrected for non-perturbative effects. From these results, we
extract the strong coupling and test the QCD predictions for its running over a
range of momentum transfers of 50-400 GeV.Comment: 10 pages, 3 figures, 3 tables; v2 as published in Phys. Lett.
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