Background:Hypoxic preconditioning (HPc) protects the neonatal brain in the setting of hypoxia-ischemia (HI). The mechanisms of protection may depend on activation of hypoxia-inducible factor (HIF-1). This study sought to clarify the role of HIF-1 after HP

We study the process e+e-→ψ(2S)π+π- with initial-state-radiation events produced at the PEP-II asymmetric-energy collider. The data were recorded with the BABAR detector at center-of-mass energies at and near the (nS) (n=2,3,4) resonances and correspond to an integrated luminosity of 520fb-1. We investigate the ψ(2S)π+π- mass distribution from 3.95 to 5.95GeV/c2, and measure the center-of-mass energy dependence of the associated e+e-→ψ(2S)π+π- cross section. The mass distribution exhibits evidence of two resonant structures. A fit to the ψ(2S)π+π- mass distribution corresponding to the decay mode ψ(2S)→J/ψπ+π- yields a mass value of 4340±16(stat) ±9(syst)MeV/c2 and a width of 94±32(stat)±13(syst)MeV for the first resonance, and for the second a mass value of 4669±21(stat) ±3(syst)MeV/c2 and a width of 104±48(stat)±10(syst)MeV. In addition, we show the π+π- mass distributions for these resonant regions. © 2014 American Physical Society.

We report the results of a study of the exclusive charmless semileptonic decays, B0→π -+ν, B +→π0 +ν, B +→ω +ν, B +→η +ν, and B +→η ′+ν (=e or μ) undertaken with approximately 462×106 BB̄ pairs collected at the Υ(4S) resonance with the BABAR detector. The analysis uses events in which the signal B decays are reconstructed with a loose neutrino reconstruction technique. We obtain partial branching fractions in several bins of q2, the square of the momentum transferred to the lepton-neutrino pair, for B0→π -+ν, B +→π0 +ν, B +→ω +ν, and B +→η +ν. From these distributions, we extract the form-factor shapes f +(q2) and the total branching fractions B(B0→π -+ν)=(1.45±0.04 stat±0.06 syst)×10 -4 (combined π - and π0 decay channels assuming isospin symmetry), B(B +→ω +ν)=(1.19±0.16 stat±0.09 syst)×10 -4 and B(B +→η +ν)=(0.38±0.05 stat±0.05 syst)×10 -4. We also measure B(B +→η ′+ν)=(0.24±0. 08 stat±0.03 syst)×10 -4. We obtain values for the magnitude of the Cabibbo-Kobayashi-Maskawa (CKM) matrix element |V ub| by direct comparison with three different QCD calculations in restricted q2 ranges of B→π +ν decays. From a simultaneous fit to the experimental data over the full q2 range and the FNAL/MILC lattice QCD predictions, we obtain |V ub|=(3.25±0.31)×10 -3, where the error is the combined experimental and theoretical uncertainty. © 2012 American Physical Society.

Searches for B mesons decaying to final states containing a baryon and a lepton are performed, where the baryon is either Λc or Λ and the lepton is a muon or an electron. These decays violate both baryon and lepton number and would be a signature of physics beyond the standard model. No significant signal is observed in any of the decay modes, and upper limits in the range (3.2-520)×10-8 are set on the branching fractions at the 90% confidence level. © 2011 American Physical Society.

We present a study of τ -→π -KS0KS0(π0) ν τ and τ -→K -KS0KS0(π0) ν τ decays using a data set of 430 million τ lepton pairs, corresponding to an integrated luminosity of 468fb -1, collected with the BABAR detector at the PEP-II asymmetric energy e +e - storage rings. We measure branching fractions of (2.31±0.04±0.08) ×10 -4 and (1.60±0.20±0.22)×10 -5 for the τ -→π -KS0KS0ν τ and τ -→π -KS0KS0π0ν τ decays, respectively. We find no evidence for τ -→K -KS0KS0ν τ and τ -→K -KS0KS0π0ν τ decays and place upper limits on the branching fractions of 6.3×10 -7 and 4.0×10 -7 at the 90% confidence level. © 2012 American Physical Society.

We present a measurement of the branching fractions of the 22 decay channels of the B0 and B+ mesons to D̄(*)D(*)K, where the D(*) and D̄(*) mesons are fully reconstructed. Summing the 10 neutral modes and the 12 charged modes, the branching fractions are found to be B(B0→D̄(*)D(*)K)=(3.68±0. 10±0.24)% and B(B+→D̄(*)D(*)K)=(4. 05±0.11±0.28)%, where the first uncertainties are statistical and the second systematic. The results are based on 429fb-1 of data containing 471×106BB̄ pairs collected at the Υ(4S) resonance with the BABAR detector at the SLAC National Accelerator Laboratory. © 2011 American Physical Society.

The decay width and mass of the Ds1(2536)+ meson are measured via the decay channel Ds1+→D*+KS0 using 385fb-1 of data recorded with the BABAR detector in the vicinity of the Υ(4S) resonance at the PEP-II asymmetric-energy electron-positron collider. The result for the decay width is Γ(Ds1+)=0.92±0.03(stat.)±0.04(syst.)MeV. For the mass, a value of m(Ds1+)=2535.08±0.01(stat.)±0.15(syst.)MeV/c2 is obtained. The mass difference between the Ds1+ and the D*+ is measured to be m(Ds1+)-m(D*+)=524. 83±0.01(stat.)±0.04(syst.)MeV/c2, representing a significant improvement compared to the current world average. The unnatural spin-parity assignment for the Ds1+ meson is confirmed. © 2011 American Physical Society.

We report updated branching fraction measurements of the color-suppressed decays B ̄0→D0π0, D *0π0, D0η, D *0η, D0ω, D *0ω, D0η ′, and D *0η ′. We measure the branching fractions (×10 -4): B(B ̄0→D0π0)=2.69±0.09±0.13, B(B ̄0→D *0π0)=3.05±0.14±0.28, B(B ̄0→D0η)=2.53±0.09±0.11, B(B ̄0→D *0η)=2.69±0.14±0.23, B(B ̄0→D0ω)=2.57±0.11±0.14, B(B ̄0→D *0ω)=4.55±0.24±0. 39, B(B ̄0→D0η ′)=1.48±0. 13±0.07, and B(B ̄0→D *0η ′)=1.49±0.22±0.15. We also present the first measurement of the longitudinal polarization fraction of the decay channel D *0ω, f L=(66.5±4.7±1.5)%. In the above, the first uncertainty is statistical and the second is systematic. The results are based on a sample of (454±5)×106 BB̄ pairs collected at the Υ(4S) resonance, with the BABAR detector at the PEP-II storage rings at SLAC. The measurements are the most precise determinations of these quantities from a single experiment. They are compared to theoretical predictions obtained by factorization, Soft Collinear Effective Theory (SCET) and perturbative QCD (pQCD). We find that the presence of final state interactions is favored and the measurements are in better agreement with SCET than with pQCD. © 2011 American Physical Society.