4,648 research outputs found
Observation of excited Ω c charmed baryons in e + e − collisions
Using the entire Belle data sample of 980 fb−1 of e+e− collisions, we present the results of a study of excited Ωc charmed baryons in the decay mode Ξ+cK−. We show confirmation of four of the five narrow states reported by the LHCb Collaboration: the Ωc(3000), Ωc(3050), Ωc(3066), and Ωc(3090)
Return to Sport and Athletic Function in an Active Population After Primary Arthroscopic Labral Reconstruction of the Hip
Background: Labral reconstruction has been advocated as an alternative to debridement for the treatment of irreparable labral tears, showing favorable short-term results. However, literature is scarce regarding outcomes and return to sport in the nonelite athletic population.
Purpose: To report minimum 1-year clinical outcomes and the rate of return to sport in athletic patients who underwent primary hip arthroscopy with labral reconstruction in the setting of femoroacetabular impingement syndrome and irreparable labral tears.
Study Design: Case series; Level of evidence, 4.
Methods: Data were prospectively collected and retrospectively analyzed for patients who underwent an arthroscopic labral reconstruction between August 2012 and December 2017. Patients were included if they identified as an athlete (high school, college, recreational, or amateur); had follow-up on the following patient-reported outcomes (PROs): modified Harris Hip Score (mHHS), Nonarthritic Hip Score (NAHS), Hip Outcome Score–Sport Specific Subscale (HOS-SSS), and visual analog scale (VAS); and completed a return-to-sport survey at 1 year postoperatively. Patients were excluded if they underwent any previous ipsilateral hip surgery, had dysplasia, or had prior hip conditions. The proportions of patients who achieved the minimal clinically important difference (MCID) and patient acceptable symptomatic state (PASS) for mHHS and HOS-SSS were calculated. Statistical significance was set at P =.05.
Results: There were 32 (14 females) athletes who underwent primary arthroscopic labral reconstruction during the study period. The mean age and body mass index of the group were 40.3 years (range, 15.5-58.7 years) and 27.9 kg/m2 (range, 19.6-40.1 kg/m2), respectively. The mean follow-up was 26.4 months (range, 12-64.2 months). All patients demonstrated significant improvement in mHHS, NAHS, HOS-SSS, and VAS (P \u3c.001) at latest follow-up. Additionally, 84.4% achieved MCID and 81.3% achieved PASS for mHHS, and 87.5% achieved MCID and 75% achieved PASS for HOS-SSS. VAS pain scores decreased from 4.4 to 1.8, and the satisfaction with surgery was 7.9 out of 10. The rate of return to sport was 78%.
Conclusion: At minimum 1-year follow-up, primary arthroscopic labral reconstruction, in the setting of femoroacetabular impingement syndrome and irreparable labral tears, was associated with significant improvement in PROs in athletic populations. Return to sport within 1 year of surgery was 78%
Measurement of Branching Fractions of Hadronic Decays of the Ω 0 c Baryon
Using a data sample of 980 fb−1 of e+e− annihilation data taken with the Belle detector operating at the KEKB asymmetric-energy e+e− collider, we report the results of a study of the decays of the Ω0ccharmed baryon into hadronic final states. We report the most precise measurements to date of the relative branching fractions of the Ω0c into Ω−π+π0, Ω−π+π−π+, Ξ−K−π+π+, and Ξ0K−π+, as well as the first measurements of the branching fractions of the Ω0c into Ξ−¯K0π+, Ξ0¯K0, and Λ¯K0¯K0, all with respect to the Ω−π+ decay. In addition, we investigate the resonant substructure of these modes. Finally, we present a limit on the branching fraction for the decay Ω0c→Σ+K−K−π+
Community-wide analysis of microbial genome sequence signatures
Genome signatures are used to identify and cluster sequences de novo from an acid biofilm microbial community metagenomic dataset, revealing information about the low-abundance community members
Comparative genomics in acid mine drainage biofilm communities reveals metabolic and structural differentiation of co-occurring archaea
Background
Metal sulfide mineral dissolution during bioleaching and acid mine drainage (AMD) formation creates an environment that is inhospitable to most life. Despite dominance by a small number of bacteria, AMD microbial biofilm communities contain a notable variety of coexisting and closely related Euryarchaea, most of which have defied cultivation efforts. For this reason, we used metagenomics to analyze variation in gene content that may contribute to niche differentiation among co-occurring AMD archaea. Our analyses targeted members of the Thermoplasmatales and related archaea. These results greatly expand genomic information available for this archaeal order.
Results
We reconstructed near-complete genomes for uncultivated, relatively low abundance organisms A-, E-, and Gplasma, members of Thermoplasmatales order, and for a novel organism, Iplasma. Genomic analyses of these organisms, as well as Ferroplasma type I and II, reveal that all are facultative aerobic heterotrophs with the ability to use many of the same carbon substrates, including methanol. Most of the genomes share genes for toxic metal resistance and surface-layer production. Only Aplasma and Eplasma have a full suite of flagellar genes whereas all but the Ferroplasma spp. have genes for pili production. Cryogenic-electron microscopy (cryo-EM) and tomography (cryo-ET) strengthen these metagenomics-based ultrastructural predictions. Notably, only Aplasma, Gplasma and the Ferroplasma spp. have predicted iron oxidation genes and Eplasma and Iplasma lack most genes for cobalamin, valine, (iso)leucine and histidine synthesis.
Conclusion
The Thermoplasmatales AMD archaea share a large number of metabolic capabilities. All of the uncultivated organisms studied here (A-, E-, G-, and Iplasma) are metabolically very similar to characterized Ferroplasma spp., differentiating themselves mainly in their genetic capabilities for biosynthesis, motility, and possibly iron oxidation. These results indicate that subtle, but important genomic differences, coupled with unknown differences in gene expression, distinguish these organisms enough to allow for co-existence. Overall this study reveals shared features of organisms from the Thermoplasmatales lineage and provides new insights into the functioning of AMD communities.United States. Dept. of Energy. Genomics:GTL (Grant DE-FG02-05ER64134)National Science Foundation (U.S.). Graduate Research Fellowshi
Phase Difference Between the Electromagnetic and Strong Amplitudes for psi(2S) and J/psi Decays into Pairs of Pseudoscalar Mesons
Using the data for 24.5x10^6 psi(2S) produced in e^+e^- annihilations at
sqrt{s}=3686 MeV at the CESR-c e^+e^- collider and 8.6x10^6 J/psi produced in
the decay psi(2S)->pi^+pi^-J/psi, the branching fractions for psi(2S) and J/psi
decays to pairs of pseudoscalar mesons, pi^+pi^-, K^+K^-, and K_S K_L, have
been measured using the CLEO-c detector. We obtain branching fractions
Br(psi(2S)->pi^+pi^-)=(7.6+-2.5+-0.6)x10^-6,
Br(psi(2S)->K^+K^-)=(74.8+-2.3+-3.9)x10^-6, Br(psi(2S)->K_S
K_L)=(52.8+-2.5+-3.4)x10^-6, and Br(J/psi->pi^+pi^-)=(1.47+-0.13+-0.13)x10^-4,
Br(J/psi->K^+K^-)=(2.86+-0.09+-0.19)x10^-4, Br(J/psi+-K_S
K_L)=(2.62+-0.15+-0.14)x10^-4, where the first errors are statistical and the
second errors are systematic. The phase differences between the amplitudes for
electromagnetic and strong decays of psi(2S) and J/psi to 0^{-+} pseudoscalar
pairs are determined by a Monte Carlo method to be
\delta(psi(2S)_{PP}=(110.5^{+16.0}_{-9.5})^o and
\delta(J/psi)_{PP}=(73.5^{+5.0}_{-4.5})^o. The difference between the two is
\Delta\delta = \delta(psi(2S))_{PP}-\delta(J/psi)_{PP}
=(37.0^{+16.5}_{-10.5})^o.Comment: 16 pages, 5 figures, submitted to PR
Measurement of the resonant and nonresonant branching ratios in Ξc0 → Ξ0K+K-
Using the entire data sample of 980 fb-1 integrated luminosity collected with the Belle detector at the KEKB asymmetric-energy e+e- collider, we present an amplitude analysis measuring the branching fractions of the Cabibbo-allowed, W-exchange resonant decay Ξc0→Ξ0φ(→K+K-) with a polarized φ and the nonresonant decay via a direct process Ξc0→Ξ0K+K-. We present these measurements, relative to the normalization mode Ξ-π+, and find branching ratios B(Ξc0→Ξ0φ(→K+K-))(BΞc0→Ξ-π+)=0.036±0.004(stat.)±0.002(syst.) and B(Ξc0→Ξ0K+K-)B(Ξc0→Ξ-π+)=0.039±0.004(stat.)±0.002(syst.), which suggest that only minor cusping peaks occur in the combinatorial background of ω∗-→Ξ0K- due to these Ξc0 decays
Measurement of the masses and widths of the ςc (2455)+ and ςc (2520)+ baryons
Using 980 fb-1 of data collected with the Belle detector operating at the KEKB asymmetric-energy e+e- collider, we report the measurements of the masses, and the first measurements of the instrinsic widths, of the ςc(2455)+ and ςc(2520)+ charmed baryons. We find M(ςc(2455)+)-M(Λc+)=166.17±0.05-0.07+0.16 MeV/c2, Γ(ςc(2455)+)=2.3±0.3±0.3 MeV/c2, M(ςc(2520)+)-M(Λc+)=230.9±0.5-0.1+0.5 MeV/c2, and Γ(ςc(2520)+)=17.2-2.1-0.7+2.3+3.1 MeV/c2, where the uncertainties are statistical and systematic, respectively. These measurements can be used to test models of the underlying quark structure of the ςc states. © 2021 authors. Published by the American Physical Society
- …