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Improved Constraints on Sterile Neutrino Mixing from Disappearance Searches in the MINOS, MINOS+, Daya Bay, and Bugey-3 Experiments.
Searches for electron antineutrino, muon neutrino, and muon antineutrino disappearance driven by sterile neutrino mixing have been carried out by the Daya Bay and MINOS+ collaborations. This Letter presents the combined results of these searches, along with exclusion results from the Bugey-3 reactor experiment, framed in a minimally extended four-neutrino scenario. Significantly improved constraints on the θ_{μe} mixing angle are derived that constitute the most constraining limits to date over five orders of magnitude in the mass-squared splitting Δm_{41}^{2}, excluding the 90% C.L. sterile-neutrino parameter space allowed by the LSND and MiniBooNE observations at 90% CL_{s} for Δm_{41}^{2}<13 eV^{2}. Furthermore, the LSND and MiniBooNE 99% C.L. allowed regions are excluded at 99% CL_{s} for Δm_{41}^{2}<1.6 eV^{2}
Physics, Astrophysics and Cosmology with Gravitational Waves
Gravitational wave detectors are already operating at interesting sensitivity
levels, and they have an upgrade path that should result in secure detections
by 2014. We review the physics of gravitational waves, how they interact with
detectors (bars and interferometers), and how these detectors operate. We study
the most likely sources of gravitational waves and review the data analysis
methods that are used to extract their signals from detector noise. Then we
consider the consequences of gravitational wave detections and observations for
physics, astrophysics, and cosmology.Comment: 137 pages, 16 figures, Published version
<http://www.livingreviews.org/lrr-2009-2
The Role of Histone Methylation and H2A.Z Occupancy during Rapid Activation of Ethylene Responsive Genes
Ethylene signaling pathway leads to rapid gene activation by two hierarchies of transcription factors with EIN3/EIL proteins as primary ones and ERF proteins as secondary ones. The role of chromatin modifications during the rapid gene activation is not known. In this work we studied trimethylated histone H3 lysine 4 (H3K4me3) and lysine 27 (H3K27me3), two opposite histone methylation marks for gene activity, during the induction course of three ethylene-responsive genes (ERF1, AtERF14 and ChiB). We found that the three genes displayed different histone modification profiles before induction. After induction, H3K4me3 was increased in the 5′ region and the gene body of ERF1, while H3K27me3 was decreased in the promoter of AtERF14. But the modification changes were later than the gene activation. Analysis of other rapidly inducible ERF genes confirmed the observation. In addition, histone H2A.Z occupancy on the three genes and the association of the H3K27me3-binding protein LHP1 with AtERF14 and ChiB were not affected by the inductive signal. However, the mutation of genes encoding H2A.Z and LHP1 attenuated and enhanced respectively the induction of target genes and altered H3K4me3. These results indicate that the induction of ethylene-responsive genes does not require immediate modulation of H3K4me3 and H3K27me3 and dissociation of LHP1 and H2A.Z from the targets, and suggest that the chromatin structure of the genes before induction is committed for transcriptional activation and that H3K4me3 is not required for ethylene-responsive gene activation, but may serve as a mark for gene activity
Patients' experiences and perceived causes of persisting discomfort following day surgery
<p>Abstract</p> <p>Background</p> <p>The aim of this study was to describe patients' experiences and perceived causes of persisting discomfort following day surgery. Earlier research has mainly covered symptoms and signs during a recovery period of up to one month, and not dealt with patients' perceptions of what causes persisting, longer-term discomfort.</p> <p>Methods</p> <p>This study is a part from a study carried out during the period May 2006 to May 2007 with a total of 298 day surgery patients. Answers were completed by 118 patients at 48 hours, 110 at seven days and 46 at three months to one open-ended question related to discomfort after day surgery constructed as follows: <it>If you are still experiencing discomfort related to the surgery, what is the reason, in your opinion</it>? Data was processed, quantitatively and qualitatively. Descriptive, inferential, correlation and content analyses were performed.</p> <p>Results</p> <p>The results suggest that patients suffer from remaining discomfort e.g. pain and wound problem, with effects on daily life following day surgery up to three months. Among patients' perceptions of <it>factors leading to discomfort </it>may be <it>wrongful or suboptimal treatment</it>, <it>type of surgery </it>or <it>insufficient access to provider/information.</it></p> <p>Conclusions</p> <p>The results have important implications for preventing and managing discomfort at home following day surgery, and for nursing interventions to help patients handle the recovery period better.</p
Relation between dietary cadmium intake and biomarkers of cadmium exposure in premenopausal women accounting for body iron stores
<p>Abstract</p> <p>Background</p> <p>Cadmium is a widespread environmental pollutant with adverse effects on kidneys and bone, but with insufficiently elucidated public health consequences such as risk of end-stage renal diseases, fractures and cancer. Urinary cadmium is considered a valid biomarker of lifetime kidney accumulation from overall cadmium exposure and thus used in the assessment of cadmium-induced health effects. We aimed to assess the relationship between dietary cadmium intake assessed by analyses of duplicate food portions and cadmium concentrations in urine and blood, taking the toxicokinetics of cadmium into consideration.</p> <p>Methods</p> <p>In a sample of 57 non-smoking Swedish women aged 20-50 years, we assessed Pearson's correlation coefficients between: 1) Dietary intake of cadmium assessed by analyses of cadmium in duplicate food portions collected during four consecutive days and cadmium concentrations in urine, 2) Partial correlations between the duplicate food portions and urinary and blood cadmium concentrations, respectively, and 3) Model-predicted urinary cadmium concentration predicted from the dietary intake using a one-compartment toxicokinetic model (with individual data on age, weight and gastrointestinal cadmium absorption) and urinary cadmium concentration.</p> <p>Results</p> <p>The mean concentration of cadmium in urine was 0.18 (+/- s.d.0.12) μg/g creatinine and the model-predicted urinary cadmium concentration was 0.19 (+/- s.d.0.15) μg/g creatinine. The partial Pearson correlations between analyzed dietary cadmium intake and urinary cadmium or blood concentrations were r = 0.43 and 0.42, respectively. The correlation between diet and urinary cadmium increased to r = 0.54 when using a one-compartment model with individual gastrointestinal cadmium absorption coefficients based on the women's iron status.</p> <p>Conclusions</p> <p>Our results indicate that measured dietary cadmium intake can reasonably well predict biomarkers of both long-term kidney accumulation (urine) and short-term exposure (blood). The predictions are improved when taking data on the iron status into account.</p
f(R) theories
Over the past decade, f(R) theories have been extensively studied as one of
the simplest modifications to General Relativity. In this article we review
various applications of f(R) theories to cosmology and gravity - such as
inflation, dark energy, local gravity constraints, cosmological perturbations,
and spherically symmetric solutions in weak and strong gravitational
backgrounds. We present a number of ways to distinguish those theories from
General Relativity observationally and experimentally. We also discuss the
extension to other modified gravity theories such as Brans-Dicke theory and
Gauss-Bonnet gravity, and address models that can satisfy both cosmological and
local gravity constraints.Comment: 156 pages, 14 figures, Invited review article in Living Reviews in
Relativity, Published version, Comments are welcom
Measurement of B(t->Wb)/B(t->Wq) at the Collider Detector at Fermilab
We present a measurement of the ratio of top-quark branching fractions R= B(t
-> Wb)/B(t -> Wq), where q can be a b, s or a d quark, using lepton-plus-jets
and dilepton data sets with integrated luminosity of ~162 pb^{-1} collected
with the Collider Detector at Fermilab during Run II of the Tevatron. The
measurement is derived from the relative numbers of t-tbar events with
different multiplicity of identified secondary vertices. We set a lower limit
of R > 0.61 at 95% confidence level.Comment: 7 pages, 2 figures, published in Physical Review Letters; changes
made to be consistent with published versio
Search for ZZ and ZW Production in ppbar Collisions at sqrt(s) = 1.96 TeV
We present a search for ZZ and ZW vector boson pair production in ppbar
collisions at sqrt(s) = 1.96 TeV using the leptonic decay channels ZZ --> ll nu
nu, ZZ --> l l l' l' and ZW --> l l l' nu. In a data sample corresponding to an
integrated luminosity of 194 pb-1 collected with the Collider Detector at
Fermilab, 3 candidate events are found with an expected background of 1.0 +/-
0.2 events. We set a 95% confidence level upper limit of 15.2 pb on the cross
section for ZZ plus ZW production, compared to the standard model prediction of
5.0 +/- 0.4 pb.Comment: 7 pages, 2 figures. This version is accepted for publication by Phys.
Rev. D Rapid Communication
Measurement of the Cross Section for Prompt Diphoton Production in p-pbar Collisions at sqrt(s) = 1.96 TeV
We report a measurement of the rate of prompt diphoton production in
collisions at using a data sample of 207
pb collected with the upgraded Collider Detector at Fermilab (CDF II).
The background from non-prompt sources is determined using a statistical method
based on differences in the electromagnetic showers. The cross section is
measured as a function of the diphoton mass, the transverse momentum of the
diphoton system, and the azimuthal angle between the two photons and is found
to be consistent with perturbative QCD predictions.Comment: 7 pages, 3 figures,revtex4. Version accepted by PRL, but with cross
section tables i
Precise measurement of the W-boson mass with the CDF II detector
We have measured the W-boson mass MW using data corresponding to 2.2/fb of
integrated luminosity collected in proton-antiproton collisions at 1.96 TeV
with the CDF II detector at the Fermilab Tevatron collider. Samples consisting
of 470126 W->enu candidates and 624708 W->munu candidates yield the measurement
MW = 80387 +- 12 (stat) +- 15 (syst) = 80387 +- 19 MeV. This is the most
precise measurement of the W-boson mass to date and significantly exceeds the
precision of all previous measurements combined
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