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Reduction in HIV-related morbidity and mortality in the highly active antiretroviral therapy (HAART) era has been unevenly distributed in the United States, and its impact on hospitalizations in urban minority populations in the public sector has been poorly characterized. We conducted a retrospective analysis of clinical and administrative data sets of an urban public hospital HIV clinic from 1997 and 1998 to identify the correlates of hospitalization early in the HAART era. 2,647 unduplicated HIV-infected patients were seen in 1997 and 1998 at the CORE Center. There were 31.7 percent women, 71 percent African-Americans and 12 percent Hispanics, and the mean age was 38 years. Men who had sex with men (MSM), injection drug users (IDU), and heterosexuals each made up one third of the population. A majority of the patients had no health insurance, and 27 percent had Medicaid. The median CD4 T cell count was 266 cells/microL, and the median viral load was 1,901 copies/ml. Hospitalizations declined significantly from 1997 (1,579) to 1998 (1,160). Admissions were confined to 25 percent of clinic patients, and 16 patients (range 8-15) had eight or more admissions. African-Americans and Hispanics had significantly more and longer hospitalizations than whites, but there was no difference by gender. IDUs had significantly more admissions than non-IDUs (28 percent vs. 21 percent respectively). On multivariate analysis, lower CD4 T cell count and higher viral load predicted risk of admission in all periods. Unexpectedly, hospitalization rates were high in patients in the highest baseline CD4 T cell stratum, > 500 cells/ml (45 of 353, 13 percent), and lowest viral load stratum, < 500 copies/ml (103 of 675, 15 percent), and rose from 1997 to 1998. HAART (i.e., 1 or 2 drug regimens) predicted fewer hospitalizations compared to 1 or 2 drug regimens. In a subset of patients who filled prescriptions on site, HAART increased from 72 percent to 85 percent and 1-2 drug regimens fell from 28 percent to 15 percent from 1997 to 1998. Regular care was associated with more frequent hospitalization and more hospital days per admission than no regular care. Hospitalized patients had significantly higher mortality than patients not hospitalized (12 percent vs. 2 percent respectively). HIV-related hospitalizations were frequent in the HAART era and decreased over time. Older age, lack of HAART, lower CD4 T cell count, higher viral load, and minority race predicted hospitalization, while gender did not. However, patients with extremely favorable CD4 T cell and viral load counts also had higher than expected hospitalization rates. Three quarters of patients had no hospitalizations, and clustering of hospitalizations in a small number of patients may enable targeted programs to reduce recidivism.

The practice of routinely administering oral contrast material to children undergoing abdominal CT for blunt trauma is controversial, primarily because of the increased risk of aspiration. The purpose of this study was to determine how often aspiration occurs in this population of children. We retrospectively studied 50 children who underwent abdominal CT scans after blunt trauma. All children received diluted 3% water-soluble oral contrast material. The medical record of each child was reviewed for evidence of aspiration pneumonia as many as 48 hr after the CT. In each patient, sections of the CT scan through the lung bases were examined for opacities. When lung opacities were identified, they were classified as atelectasis, confusion, laceration, or nonspecific. We made attenuation measurements of lung opacities larger than 1 cm, and each measurement was compared with the attenuation measurement of contrast material in that patient's stomach. Student's two-tailed t test was used to compare the two measurements. Four patients were febrile after the CT scan, but in none was aspiration pneumonia suspected to be the cause. The remaining 46 patients did not have any clinical evidence of aspiration. Twelve of the 50 patients had pulmonary opacities revealed by CT that were sufficiently large that attenuation measurements could be obtained. The opacity in one of these patients was classified as nonspecific, and the attenuation was as high as that of contrast material in the stomach. No clinically symptomatic episodes of aspiration pneumonia were found in 50 pediatric patients with blunt trauma who were given oral contrast material for abdominal CT. Although one of the children had CT findings that suggested clinically silent aspiration of oral contrast material, no evidence was found that administration of oral contrast material was harmful.

We search for the reaction channel $e^+ e^- \to ηη\,J/ψ$ in a data sample with center-of-mass energies from 4.226 to 4.950~GeV, which was collected by the BESIII detector operating at the Beijing Electron Positron Collider (BEPCII). The data analysis is performed with two different methods, exclusively and semi-inclusively, which enabling a comparison and combination of the results. Only in a few cases a statistical significance of the cross sections with more than $3σ$ is observed with one of the methods. Only at 4.750~GeV the significance of the cross section measurement is 8.9$σ$ (observation) with the exclusive analysis and 3.4$σ$ (evidence) with the semi-inclusive analysis. Therefore, the corresponding upper limits of the cross section at the 90% confidence level are determined. The energy dependent results show clear deviations from the the line shape expected from three-body phase space alone. Since the statistical significance for almost all center-of-mass energies is low, the upper limits for the reaction channel $e^+ e^- \to ηη\,J/ψ$ also serve as limits for the existence of a possible isospin partner to the charmonium-like isospin triplet $Z_{\rm c}(3900)$ which decays t

The time-dependent $CP$ asymmetry in $B^{0}\!\to{J\mskip-3mu/\mskip-2muψ}ρ(770)^0$ decays is measured using proton-proton collision data corresponding to an integrated luminosity of $6\,\text{fb}^{-1}$, collected with the LHCb detector at a center-of-mass energy of $13\,\text{TeV}$ during the years 2015-2018. The $CP$-violation parameters for this process are determined to be $2β^{\rm eff}_{c\bar{c}d} = 0.710 \pm 0.084 \pm 0.028\,\text{rad}$ and $|λ| = 1.019 \pm 0.034 \pm 0.009$, where the first uncertainty is statistical and the second systematic. This constitutes the first observation of time-dependent $CP$ violation in $B$ meson decays to charmonium final states mediated by a $b\!\to{c\bar{c}d}$ transition. These results are consistent with, and two times more precise than, the previous LHCb measurement based on a data sample collected at 7 and $8\,\text{TeV}$ corresponding to an integrated luminosity of $3\,\text{fb}^{-1}$. Assuming approximate SU(3) flavor symmetry, these two measurements are combined to set the most stringent constraint on the enguin contribution, $Δφ_{s}$, to the $CP$-violating phase $φ_{s}$ in $B^{0}_{s}\!\to{J\mskip-3mu/\mskip-2muψ}φ(1020)$ decays, yieldin

The collinear and transverse-momentum-dependent jet fragmentation function and the radial profile for $B^{\pm}$ mesons in jets are measured. The $B^{\pm}$ mesons are reconstructed through the $J/ψ(\to μ^{+} μ^{-}) K^{\pm}$ decay channel using proton-proton collision data collected during 2016-2018 with the LHCb detector at a center-of-mass energy of $\sqrt{s}=13$ TeV, corresponding to an integrated luminosity of $5.4$ fb$^{-1}$. The results complement recent measurements of jet fragmentation functions for heavy-flavor hadrons and suggest a growing contribution of gluon fragmentation to $B^{\pm}$ mesons as the jet transverse momentum increases.

Based on a sample of $(10087\pm44)\times10^{6}$ $J/ψ$ events collected with the BESIII detector, a partial-wave analysis of $ J/ψ\to Λ\bar{ Σ}^0η+\mathrm{c.c} $ is performed for the first time. The dominant contributions are found to be excited $Λ$ states with $J^P=1/2^-$ and $J^P=1/2^+$ in the $ηΛ$ mass spectra. The measured masses and widths are $M=1668.8\pm3.1\pm21.2$ MeV/$c^2$ and $Γ=52.7\pm4.2\pm17.8$ MeV for the $Λ(1670)$, and $M=1881.5\pm16.5\pm20.3$ MeV/$c^2$ and $Γ=82.4\pm18.2\pm8.9$ MeV for the $Λ(1810)$, respectively. The branching fraction is determined to be $ \mathcal{B}(J/ψ\to Λ\bar{ Σ}^0η+\mathrm{c.c}) $ = $(3.44 \pm 0.11 \pm 0.13) \times 10^{-5}$. The first uncertainties are statistical and the second systematic.

Using $(10\,087 \pm 44) \times 10^6$ $J/ψ$ events collected with the BESIII detector, we perform the first amplitude analysis of the process $J/ψ\toγηπ^0$. The decay is dominated by the intermediate processes $J/ψ\toπ^0 b_1(1235)^0 \toγηπ^0$, $J/ψ\toπ^{0}ρ(1450)^0 \toγηπ^0$ and $J/ψ\toηh_1(1170) \toγηπ^0$. Contributions from $J/ψ\toγa_0(980)^0\toγηπ^0$, $J/ψ\toγa_2(1320)^0\toγηπ^0$ and $J/ψ\toγa_2(1700)^0\toγηπ^0$ are observed with a statistical significance exceeding $5σ$, constituting the first observation of radiative transitions of $J/ψ$ to isospin-triplet scalar mesons. The total branching fraction of $J/ψ\toγηπ^0$ is measured to be $(25.7\pm0.3\pm1.5)\times 10^{-6}$, where the first uncertainty is statistical and the second systematic. This result is consistent with the previous measurement, with the precision improved by more than a factor of two.

A search for the rare decays $B_{(s)}^0\to J/ψγ$ is performed with proton-proton collision data collected by the LHCb experiment, corresponding to integrated luminosities of $3~\rm{fb}^{-1}$ at centre-of-mass energies of 7 and 8 TeV, and $6~\rm{fb}^{-1}$ at 13 TeV. Assuming no contribution from $B^0\to J/ψγ$ decay, an upper limit is set on the branching fraction $\mathcal{B}(B_{s}^0\to J/ψγ)&lt;2.9\times10^{-6}$ at the 90% confidence level. If instead no contribution from $B_{s}^0\to J/ψγ$ decay is assumed, the limit is $\mathcal{B}(B^0\to J/ψγ)&lt;2.5\times10^{-6}$ at the 90% confidence level. These results supersede the previous LHCb results, with the limit for $B_{s}^0\to J/ψγ$ improved by a factor of 2.5.

Based on a novel method for producing antineutrons via $J/ψ$ decays, we report a study of $\bar{n}p$ inelastic scattering into final states containing kaons. The analysis uses $(10087\pm44)\times 10^6$ $J/ψ$ events collected at the BESIII detector operating at the BEPCII storage ring. Antineutrons are produced via $J/ψ\to p π^{-} \bar{n}$ decays and tagged by the detected protons and pions, resulting in antineutron momenta ranging from 0 to 1174~MeV/$c$, while target protons are provided by the hydrogen in the beam-pipe material. The flux-averaged cross sections of the reactions $\bar{n}p \rightarrow K^{+}K^{-}π^{+}$ and $\bar{n}p \rightarrow K^{+}K^{-}π^{+}π^{0}$ over this antineutron momentum spectrum are measured to be $0.53^{+0.15}_{-0.12} \pm 0.08$~mb and $1.09^{+0.36}_{-0.30} \pm 0.31$~mb, respectively, where the first uncertainties are statistical and the second are systematic. Due to limited statistics, the intermediate states in these processes are not quantitatively investigated. The observation of clean antineutron-proton scattering candidates indicates the potential of this approach for future investigations of antineutron-proton interactions.

Based on a sample of $(10087 \pm 44) \times 10^6$ $J/ψ$ events collected with the BESIII detector at BEPCII, we report the first observation of the decay $J/ψ\rightarrow K^- Σ^0 \barΞ^++c.c.$. A partial wave analysis is performed to investigate the involved excited states. In addition to the well-established $Ξ(1690)$, a new doubly-strange hyperon $Ξ(1720) $ is observed decaying to $K^- Σ^0$ with a mass of $1721.0 \pm 5.2_{\rm stat.} \pm 3.4_{\rm syst.} ~{\rm MeV}/c^2$ and a width of $31.3 \pm 18.3_{\rm stat.} \pm 15.4_{\rm syst.} ~{\rm MeV}$, with a statistical significance exceeding $10σ$. The spin-parity hypothesis testing across various quantum number configurations reveals that the spin-parity of $Ξ(1720)$ favors $J^P = {\frac{3}{2}}^+$. Furthermore, the branching fraction of $J/ψ\rightarrow K^- Σ^0 \barΞ^++c.c.$ is determined to be $(2.68 \pm 0.04_{\rm stat.} \pm 0.17_{\rm syst.}) \times 10^{-5}$.

The first observation of the $χ_{c1}(3872)\rightarrow J\mskip -3mu/\mskip -2muψμ^+μ^-$ decay is reported using proton-proton collision data recorded with the LHCb detector corresponding to an integrated luminosity of $9fb^{-1}$. The decay mode is observed for the first time, with a significance of $6.5σ$. Its branching fraction is measured relative to the $χ_{c1}(3872)\rightarrow J\mskip -3mu/\mskip -2muψπ^+π^-$ decay mode \begin{align*} \frac{\cal{BF}(χ_{c1}(3872)\rightarrow J\mskip -3mu/\mskip -2muψμ^+μ^-)}{\cal{BF}(χ_{c1}(3872)\rightarrow J\mskip -3mu/\mskip -2muψπ^+π^-)} = \left(1.68\pm 0.32\pm 0.05\right)\times10^{-3}, \end{align*} where the first uncertainty includes both statistical contributions and systematic contributions which are uncorrelated between data-taking periods, and the second represents the systematic contributions that are correlated between data-taking periods.

Using a sample of $(10087\pm44) \times 10^{6}$ $J/ψ$ events collected with the BESIII detector at the BEPCII collider, the first evidence for the doubly OZI-suppressed decay $η_{c} \to ωφ$ is reported with a significance of 4.0$σ$. The branching fraction of $η_{c} \to ωφ$ is measured to be $\mathcal{B}(η_{c} \to ωφ) = (3.86 \pm 0.92 \pm 0.62) \times 10^{-5}$, where the first uncertainty is statistical and the second is systematic. This result provides valuable insights into the underlying mechanisms of charmonium decays, particularly for processes such as $η_{c} \to VV$ (where $V$ represents a vector meson).

Branching fraction ratios between the decays $B^{0}_{(s)} \rightarrow J/ψη^{(\prime)}$ are measured using proton-proton collision data collected by the LHCb experiment at centre-of-mass energies of $7$, $8$ and $13~\textrm{TeV}$, corresponding to an integrated luminosity of $9~ \textrm{fb}^{-1}$. The measured ratios of these branching fractions are $\frac{BF(B^{0} \rightarrow J/ψη^{\prime})}{BF(B^{0} \rightarrow J/ψη)} = 0.48 \pm 0.06 \pm 0.02 \pm 0.01$ and $\frac{BF(B^{0}_{s} \rightarrow J/ψη^{\prime})}{BF(B^{0}_{s} \rightarrow J/ψη)} = 0.80 \pm 0.02 \pm 0.02 \pm 0.01$, where the uncertainties are statistical, systematic and related to the precision of the $η^{(\prime)}$ branching fractions, respectively. They are used to constrain the $η/η^{\prime}$ mixing angle, $φ_{P}$, and to probe the presence of a possible glueball component in the $η^{\prime}$ meson, described by the gluonic mixing angle $φ_{G}$. The obtained results are $φ_{P} = (41.6^{+1.0}_{-1.2})^\circ$ and $φ_{G} = (28.1^{+3.9}_{-4.0})^\circ$, where the uncertainties are statistically dominated. While the value of $φ_{P}$ is compatible with existing experimental determinations and theoretical calculations, the angle $φ

By analyzing $(10087 \pm 44)\times10^6$ $J/ψ$ events collected with the BESIII detector at the BEPCII, the decays $J/ψ\to Ξ^0\barΛK^0_S+c.c.$, $J/ψ\to Ξ^0\barΣ^0 K^0_S+c.c.$, and $J/ψ\to Ξ^0\barΣ^- K^++c.c.$ are observed for the first time. Their branching fractions are determined to be $\mathcal{B}(J/ψ\to Ξ^0\barΛK^0_S+c.c.)=(3.76\pm 0.14\pm 0.23)\times10^{-5}$, $\mathcal{B}(J/ψ\to Ξ^0\barΣ^0 K^0_S+c.c.)=(2.24\pm 0.32\pm 0.31)\times10^{-5}$, and $\mathcal{B}(J/ψ\to Ξ^0\barΣ^- K^++c.c.)=(5.64\pm 0.17\pm 0.28)\times10^{-5}$, where the first uncertainties are statistical and the second systematic.

A partial-wave analysis is performed on the decay $J/ψ\toγπ^{0}π^{0}π^{0}$ within the $π^{0}π^{0}π^{0}$ invariant-mass region below 1.6 GeV$/c^{2}$, using $(10.09~\pm~0.04)\times10^{9} ~J/ψ$ events collected with the BESIII detector. Significant isospin-violating decays of $η(1405)$ and $f_1(1420)$ into $f_0(980)π^{0}$ are observed. For the first time, three axial-vectors, $f_1(1285)$, $f_1(1420)$ and $f_1(1510)$, are observed to decay into $π^{0}π^{0}π^{0}$. The product branching fractions of these resonances are reported.

Based on a data sample of $(10087 \pm 44) \times 10^6$ $J/ψ$ events taken with the BESIII detector, we search for the flavor-changing neutral current charmonium decay $J/ψ\to D^{0} μ^{+} μ^{-} + \text{c.c.}$. No significant signal above the background is observed, and the upper limit on its branching fraction is set to be $\mathcal{B}(J/ψ\to D^{0}μ^{+}μ^{-} + \text{c.c.} ) &lt; 1.1 \times 10^{-7}$ at the 90% confidence level. This marks the first search for a flavor-changing neutral current charmonium decay involving muons in the final state.

Using $(10087\pm44)\times10^{6}$ $J/ψ$ events collected with the BESIII detector, a full angular distribution analysis is carried out on the process $J/ψ\rightarrowΛ\barΛ\rightarrow nπ^{0}\bar{p}π^{+}+c.c.$ The decay parameters $α_{0}$ for $Λ\rightarrow nπ^{0}$ and $\barα_{0}$ for $\barΛ\rightarrow \bar{n}π^{0}$ are measured to be $0.668\pm0.007\pm0.002$ and $-0.677\pm0.007\pm0.003$, respectively, yielding the most precise test for $CP$ symmetry of neutral decays of $Λ$, $A_{CP}^{0}=(α_{0}+\barα_{0})/(α_{0}-\barα_{0})$, to be $-0.006\pm0.007\pm0.002$. The ratios $α_{0}/α_{-}$ and $\barα_{0}/α_{+}$ are determined to be $0.884\pm0.013\pm0.006$ and $0.885\pm0.013\pm0.004$, where $α_{-}$ and $α_{+}$ are the decay parameters of $Λ\rightarrow pπ^{-}$ and $\barΛ\rightarrow\bar{p}π^{+}$, respectively. The ratios, found to be smaller than unity by more than $5σ$, confirm the presence of the $ΔI = 3/2$ transition in the $Λ$ and $\barΛ$ decays, which is expected to improve the theoretical calculations for strong and weak phases, and $A_{CP}$, in hyperon decays. In all results, the first and second uncertainties are statistical and systematic, respectively.

Based on a sample of $ (10.087\pm 0.044)\times 10^{9} J/ψ$ events collected by the BESIII detector at the BEPCII collider, we perform the first search for the lepton number violating decay $η\to π^+π^+ e^-e^- + \text{c.c.}$ No signal is found, and an upper limit on the branching fraction of $η\to π^+π^+ e^-e^- + c.c.$ is set to be $4.6 \times 10^{-6}$ at the 90\% confidence level.

A time-integrated angular analysis of the decay $B^0_s \rightarrow J/ψ\overline{K}{}^{*}\kern-1pt(892)^{0}$, with $J/ψ\rightarrow μ^{+} μ^{-}$ and $\overline{K}{}^{*}\kern-1pt(892)^{0} \rightarrow K^{-} π^{+}$, is presented. The analysis employs a sample of proton-proton collision data collected by the LHCb experiment during 2015-2018 at a centre-of-mass energy of $13 \text{TeV}$, corresponding to an integrated luminosity of $6 \text{fb}^{-1}$. A simultaneous maximum-likelihood fit is performed to the angular distributions in bins of the $K^{-} π^{+}$ mass. This fit yields measurements of the $CP$-averaged polarisation fractions and $CP$ asymmetries for the P-wave component of the $K^{-} π^{+}$ system. The longitudinal and parallel polarisation fractions are determined to be $f_{0} = 0.534 \pm 0.012 \pm 0.009$ and $f_{\parallel} = 0.211 \pm 0.014 \pm 0.005$, respectively, where the first uncertainty is statistical and the second is systematic. The $CP$ asymmetries are measured with $3$-$7\%$ precision and are found to be consistent with zero. These measurements, along with an updated determination of the branching fraction relative to the $B^0 \rightarrow J/ψK^{*0}$ decay, are comb