A precise measurement of the cross section for the process e + e − → K + K − ( γ ) from threshold to an energy of 5 GeV is obtained with the initial-state radiation (ISR) method using 232 fb − 1 ...of data collected with the BABAR detector at e + e − center-of-mass energies near 10.6 GeV. The measurement uses the effective ISR luminosity determined from the e + e − → μ + μ − ( γ ) γ ISR process with the same data set. The corresponding lowest-order contribution to the hadronic vacuum polarization term in the muon magnetic anomaly is found to be a K K , LO μ = ( 22.93 ± 0.18 stat ± 0.22 syst ) × 10 − 10 . The charged kaon form factor is extracted and compared to previous results. Its magnitude at large energy significantly exceeds the asymptotic QCD prediction, while the measured slope is consistent with the prediction.
Preeclampsia is a multifactorial pathology with negative outcomes in affected patients in both the peripartum and postpartum period. Black patients in the United States, when compared to their White ...and Hispanic counterparts, have higher rates of preeclampsia. This article aims to review the current literature to investigate how race, social determinants of health, and genetic profiles influence the prevalence and outcomes of patients with preeclampsia. Published studies utilized in this review were identified through PubMed using authors' topic knowledge and a focused search through a Medline search strategy. These articles were thoroughly reviewed to explore the contributing biosocial factors, genes/biomarkers, as well as negative outcomes associated with disparate rates of preeclampsia. Increased rates of contributing comorbidities, including hypertension and obesity, which are largely associated with low access to care in Black patient populations lead to disparate rates of preeclampsia in this population. Limited research shows an association between increased rate of preeclampsia in Black patients and specific APOL1, HLA-G, and PP13 gene polymorphisms as well as factor V Leiden mutations. Further research is required to understand the use of certain biomarkers in predicting preeclampsia within racial populations. Understanding contributing biosocial factors and identifying genes that may predispose high-risk populations may help to address the disparate rates of preeclampsia in Black patients as described in this review. Further research is required to understand if serum, placental, or urine biomarkers may be used to predict individuals at risk of developing preeclampsia in pregnancy. KEY POINTS: · Prevalence of preeclampsia in the U.S. is higher in Black patients compared to other racial groups.. · Patients with preeclampsia are at risk for poorer health outcomes both during and after delivery.. · Limited research suggests specific biomarkers or gene polymorphisms contribute to this difference; however, explanations for this disparity are multifactorial and further investigation is necessary..
An angular analysis of the decay $\bar{B}$ → D*ℓ ¯$\bar{ν}_ℓ$, ℓϵ {e,μ}, is reported using the full e+e- collision data set collected by the BABAR experiment at the Υ(4S) resonance. One B meson from ...the Υ(4S) → $B\bar{B}$ decay is fully reconstructed in a hadronic decay mode, which constrains the kinematics and provides a determination of the neutrino momentum vector. The kinematics of the semileptonic decay is described by the dilepton mass squared, q2, and three angles. The first unbinned fit to the full four-dimensional decay rate in the standard model is performed in the so-called Boyd-Grinstein-Lebed approach, which employs a generic q2 parametrization of the underlying form factors based on crossing symmetry, analyticity, and QCD dispersion relations for the amplitudes. A fit using the more model-dependent Caprini-Lellouch-Neubert (CLN) approach is performed as well. Our form factor shapes show deviations from previous fits based on the CLN parametrization. The latest form factors also provide an updated prediction for the branching fraction ratio $\mathscr{R}$(D*) ≡ $\mathscr{B}$($\bar{B}$ → D* τ¯ $\bar{ν}_τ$)/$\mathscr{B}$($\bar{B}$ → D*ℓ¯ $\bar{ν}_ℓ$) = 0.253 ± 0.005 . Finally, using the well-measured branching fraction for the $\bar{B}$ → D*ℓ¯ $\bar{ν}_ℓ$ decay, a value of |Vcb| = (38.36 ± 0.90) × 10⁻3 is obtained that is consistent with the current world average for exclusive $\bar{B}$ → D (*)ℓ⁻$\bar{ν}_ℓ$ decays and remains in tension with the determination from inclusive semileptonic B decays to final states with charm.
We present simulations of Keck Interferometer ASTRA and VLTI GRAVITY observations of mock star fields in orbit within ~50 mas of Sgr A super(*). Dual-field phase referencing techniques, as ...implemented on ASTRA and planned for GRAVITY, will provide the sensitivity to observe Sgr A super(*) with long-baseline infrared interferometers. Our results show an improvement in the confusion noise limit over current astrometric surveys, opening a window to study stellar sources in the region. The GRAVITY instrument will yield a more compact and symmetric point-spread function, providing an improvement in confusion noise which will not depend as strongly on position angle. Our Keck results show file ability to characterize the star field as containing zero, few, or many bright stellar sources. ASTRA and GRAVITY both have the potential to detect and monitor sources very close to Sgr A super(*). Early characterizations of the field by ASTRA, including the possibility of a precise source detection, could provide valuable information for future GRAVITY implementation and observation.
This study aims to determine whether the dynamic ion speciation (DIS) model, as introduced in part I, can predict the ion composition in freshly prepared simulated milk ultrafiltrate (SMUF) under ...various conditions, e.g. pH, ionic strength and presence of various polyphosphates. Experiments were carried out in freshly prepared SMUF enriched with different salts. The model predictions were in satisfactory agreement with experimental results for all conditions. Moreover, specific ion effects were taken into account in the model, where sodium ions were not counted as equivalent to potassium ions due to differences in hydration properties. Polyphosphates, in particular sodium hexametaphosphate (SHMP), were well integrated into the DIS model with reasonable association constants and solubility products. The DIS model suggests that SHMP displays chain polyphosphate properties, which provides better understanding of its interaction with cations. The DIS model appears to be a robust and versatile tool to describe ion equilibria in SMUF.
A study of the two-body decays B±→Xcc¯K±, where Xcc¯ refers to one charmonium state, is reported by the BABAR Collaboration using a data sample of 424 fb−1. The absolute determination of branching ...fractions for these decays are significantly improved compared to previous BABAR measurements. Evidence is found for the decay B+→X(3872)K+ at the 3σ level. The absolute branching fraction BB+→X(3872)K+=2.1±0.6(stat)±0.3(syst)×10−4 is measured for the first time. It follows that BX(3872)→J/ψπ+π−=(4.1±1.3)%, supporting the hypothesis of a molecular component for this resonance.
We report on the successful science verification phase of a new observing mode at the Keck Interferometer, which provides a line-spread function width and sampling of 150 km s{sup -1} at the K'-band, ...at a current limiting magnitude of K' {approx} 7 mag with a spatial resolution of {lambda} / 2 B {approx} 2.7 mas and a measured differential phase stability of unprecedented precision (3 mrad at K = 5 mag, which represents 3 {mu} as on the sky or a centroiding precision of 10{sup -3}). The scientific potential of this mode is demonstrated by the presented observations of the circumstellar disk of the evolved Be-star 48 Lib. In addition to indirect methods such as multi-wavelength spectroscopy and polarimetry, the spectro-interferometric astrometry described here provides a new tool to directly constrain the radial density structure in the disk. For the first time, we resolve several Pfund emission lines, in addition to Br {gamma}, in a single interferometric spectrum, with adequate spatial and spectral resolution and precision to analyze the radial disk structure in 48 Lib. The data suggest that the continuum and Pf-emission originates in significantly more compact regions, inside the Br {gamma}-emission zone. Thus, spectro-interferometric astrometry opens the opportunity to directly connect the different observed line profiles of Br {gamma} and Pfund in the total and correlated flux to different disk radii. The gravitational potential of a rotationally flattened Be star is expected to induce a one-armed density perturbation in the circumstellar disk. Such a slowly rotating disk oscillation has been used to explain the well-known periodic V/R spectral profile variability in these stars, as well as the observed V/R cycle phase shifts between different disk emission lines. The differential line properties and linear constraints set by our data are consistent with theoretical models and lend direct support to the existence of a radius-dependent disk density perturbation. The data also show decreasing gas rotation velocities at increasing stellocentric radii as expected for Keplerian disk rotation, assumed by those models.
The photon spectrum in the inclusive electromagnetic radiative decays of the B meson, B → X s γ plus B → X d γ , is studied using a data sample of ( 382.8 ± 4.2 ) × 10 6 Υ ( 4 S ) → B ¯¯¯ B decays ...collected by the BABAR experiment at SLAC. The spectrum is used to extract the branching fraction B ( B → X s γ ) = ( 3.21 ± 0.33 ) × 10 − 4 for E γ > 1.8 GeV and the direct C P asymmetry A C P ( B → X s + d γ ) = 0.057 ± 0.063 . The effects of detector resolution and Doppler smearing are unfolded to measure the photon energy spectrum in the B meson rest frame.
Here, we study the processes e+e– → π+π–π0π0π0γ and π+π–π0π0ηγ in which an energetic photon is radiated from the initial state. The data are collected with the BABAR detector at SLAC. About 14 000 ...and 4700 events, respectively, are selected from a data sample corresponding to an integrated luminosity of 469 fb–1. The invariant mass of the hadronic final state defines the effective e+e– center-of-mass energy. From the mass spectra, the first precise measurement of the e+e– → π+π–π0π0π0 cross section and the first measurement ever of the e+e– → π+π–π0π0η cross section are performed. The center-of-mass energies range from threshold to 4.35 GeV. The systematic uncertainty is typically between 10% and 13%. The contributions from ωπ0π0, ηπ+π–, and other intermediate states are presented. We observe the J/ψ and ψ(2S) in most of these final states and measure the corresponding branching fractions, many of them for the first time.
Following acute respiratory distress syndrome (ARDS), joblessness is common but poorly understood.
To evaluate the timing of return to work after ARDS, and associated risk factors, lost earnings, and ...changes in healthcare coverage Methods: Over 12-month longitudinal follow-up, ARDS survivors from 43 U.S. ARDSNet hospitals provided employment and healthcare coverage data via structured telephone interviews. Factors associated with the timing of return to work were assessed using Fine and Gray regression analysis. Lost earnings were estimated using Bureau of Labor Statistics data.
Of 922 consenting survivors, 386 (42%) were employed before ARDS (56% male; mean ± SD age, 45 ± 13 yr), with seven dying by 12-month follow-up. Of 379 previously employed 12-month survivors, 166 (44%) were jobless at 12-month follow-up. Accounting for competing risks of death and retirement, half of enrolled and previously employed survivors returned to work by 13 weeks after hospital discharge, with 68% ever returning by 12 months. Delays in return to work were associated with longer hospitalization and older age among nonwhite survivors. Over 12-month follow-up, 274 (71%) survivors accrued lost earnings, averaging $26,949 ± $22,447 (60% of pre-ARDS annual earnings). Jobless survivors experienced a 14% (95% confidence interval, 5-22%; P = 0.002) absolute decrease in private health insurance (from 44% pre-ARDS) and a 16% (95% confidence interval, 7-24%; P < 0.001) absolute increase in Medicare and Medicaid (from 33%).
At 12 months after ARDS, nearly one-half of previously employed survivors were jobless. Post-ARDS joblessness is associated with readily identifiable patient and hospital variables and accompanied by substantial lost earnings and a shift toward government-funded healthcare coverage.
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