A Curve Approximated Hysteresis Model for Steel Bridge Columns

In this paper，a curve approximated hysteresis model for SDF analysis is proposed to predict the nonlinear response of bridges supported by steel columns with suitable scope of severe damaged deterioration domain. Instead of multiple straight lines，a series of curves are adopted to precisely describe complicated force-displacement hysteresis behavior of the column. The P-δ effect, hardeing effect in unloading-reloading hysteresis loops, deterioration of strength and stiffness are taken into account. Parameters of proposed hysteresis model for three types of steel pier specimens used in this study are calibrated by six static cyclic tests. To verify the accuracy of the proposed model, eleven pseudo-dynamic tests are conducted. By comparing the simulation and the test results，the differences between the predicted nonlinear seismic response using the proposed model and pseudo-dynamic tests are found to be， averagely， 5% in maximum response displacement，22% in residual displacement and 4% in the amount of energy dissipation

Point-of-Care Ultrasound: New Concepts and Future Trends

Ultrasound (US) technology, with major advances and new developments, has become an essential and first-line imaging modality for clinical diagnosis and interventional treatment. US imaging has evolved from one-dimensional, twodimensional to three-dimensional display, and from static to real-time imaging, as well as from structural to functional imaging. Based on its portability and advanced digital imaging technique, US was first adopted by emergency medicine in the 1980s and gradually gained popularity among other specialists for clinical diagnosis and interventional treatment. Point-of-Care Ultrasound (POCUS) was then proposed as a new concept and developed for new uses, which greatly extended clinical US applications. Nowadays, artificial intelligence (AI), cloud computing, 5G network, robotics, and remote technologies are starting to be integrated into US equipment. US systems have gradually evolved to an intelligent terminal platform with powerful imaging and communication tools. In addition, specialized US machines tend to be more suitable and important to meet increasing demands and requirements by various clinical specialties and departments. In this article, we review current US technology and POCUS as new concepts and its future trends, as well as related technological developments and clinical applications

Incremental value of non-invasive myocardial work for the evaluation and prediction of coronary microvascular dysfunction in angina with no obstructive coronary artery disease

BackgroundEvidence suggests that patients suffering from angina with no obstructive coronary artery disease (ANOCA) experience coronary microvascular dysfunction (CMD). We aimed to understand the diagnosis value of noninvasive myocardial work indices (MWIs) with left ventricular pressure-strain loop (LV PSL) by echocardiography in ANOCA patients with CMD.Methods97 patients with ANOCA were recruited. All subjects underwent standard echocardiography with traditional ultrasound parameters, two-dimensional speckle-tracking echocardiography with global longitudinal strain (GLS), LV PSL with MWIs include global work index (GWI), global constructive work (GCW), global waste work (GWW) and global work efficiency (GWE). In addition, all enrolled cases underwent high-dose adenosine stress echocardiography (SE) with coronary flow velocity reserve (CFVR). CMD was defined as CFVR <2.0.ResultsOf the 97 patients with ANOCA, 52 were placed in the CMD group and 45 in the control group. GWI and GCW were decreased significantly in the CMD group compared with the control group (P < 0.001 for both). GWI and GCW were moderately correlated with CFVR (r = 0.430, P < 0.001 and r = 0.538, P < 0.001, respectively). In the multiple logistic regression analyses, GCW was identified as the only independent echocardiography parameter associated with CMD after adjusting for age and baseline APV [OR (95%CI) 1.009 (1.005–1.013); P < 0.001]. Moreover, the best predictor of CMD in patients with ANOCA using receiver operating characteristic (ROC) curve was GWI and GCW, with an area under the curve (AUC) of 0.800 and 0.832, sensitivity of 67.3% and 78.8%, specificity of 80.0% and 75.6%, respectively.ConclusionMWIs with LV PSL is a new method to detect LV systolic function noninvasively in ANOCA patients with CMD

Meta analysis of heavy metal and pesticide pollution status of nine medicinal and edible substances

ObjectiveTo evaluate the heavy metal and pesticide pollution status of nine medicinal and edible substances， including Eucommia ulmoides leaves， Codonopsis pilosula， Cistanche deserticola， Dendrobium candidum， Astragalus membranaceus， Panax quinquefolium， Gastrodia elata， Ganoderma lucidum， and Corni Fructus.MethodsPubMed， China National Knowledge Network （CNKI）， VIP， and Wanfang databases were searched to obtain research literature published from 2000 to 2022 on heavy metals， pesticides， and environmental pollutants in nine medicinal and edible substances. The literature was screened according to the inclusion and exclusion criteria， and the included studies were analyzed and pooled into estimates using meta-analysis.ResultsA total of 106 studies encompassing seven heavy metals， including lead （Pb）， cadmium （Cd）， mercury （Hg）， arsenic （As）， chromium （Cr）， copper （Cu）， and nickel （Ni）， and 42 pesticides， including organochlorine， pyrethroid， and organophosphorus， of nine types of medicinal and edible substances used as food collected from 23 provinces （municipalities） were comprehensively analyzed. The average heavy metal content in the medicinal and edible substances used as food was 0.22 mg/kg （95%CI： 0.13~0.39）， and the average heavy metal content of Eucommia ulmoides leaves was the highest （2.80 mg/kg， 95%CI： 0.75~10.37）， followed by Dendrobium candidum with an average value of 0.30 mg/kg （95%CI： 0.18~0.49）. The average value of heavy metals in the other medicinal and edible substances was lower than 0.30 mg/kg. Among the seven heavy metals analyzed， the Cu exhibited the highest content， followed by Cd and Pb. Subgroup analysis showed that the contents of the seven heavy metals in medicinal and edible substances collected from different locations had high heterogeneity （P<0.05）. The meta-analysis showed that heterogeneity existed in the mean values of 42 pesticides （P<0.05）， and the total mean values of pentachloronitrobenzene， BHC and DDT in Dendrobium candidum， Panax quinquefolium， Cistanche deserticola， Astragalus membranaceus， and Gastrodia elata were the highest.ConclusionThere are differences in the categories and contamination levels of heavy metals and pesticides in medicinal and edible substances. Heavy metal pollution is related to the origin and type of medicinal and edible substances. Prohibited pesticides can be detected in certain medicinal and edible substances， and further traceability analyses of pollutants in medicinal and edible substances should be conducted. The supervision and monitoring of the production and processing of medicinal and edible substances should be strengthened

Observation of ηc→ωω\eta_c\to\omega\omega in J/ψ→γωωJ/\psi\to\gamma\omega\omega

Using a sample of $(1310.6\pm7.0)\times10^6$ $J/\psi$ events recorded with the BESIII detector at the symmetric electron positron collider BEPCII, we report the observation of the decay of the $(1^1 S_0)$ charmonium state $\eta_c$ into a pair of $\omega$ mesons in the process $J/\psi\to\gamma\omega\omega$. The branching fraction is measured for the first time to be $\mathcal{B}(\eta_c\to\omega\omega)= (2.88\pm0.10\pm0.46\pm0.68)\times10^{-3}$, where the first uncertainty is statistical, the second systematic and the third is from the uncertainty of $\mathcal{B}(J/\psi\to\gamma\eta_c)$. The mass and width of the $\eta_c$ are determined as $M=(2985.9\pm0.7\pm2.1)\,$MeV/$c^2$ and $\Gamma=(33.8\pm1.6\pm4.1)\,$MeV.Comment: 13 pages, 6 figure

Observation of Ds+→pnˉD^+_s\rightarrow p\bar{n} and confirmation of its large branching fraction

The baryonic decay $D^+_s\rightarrow p\bar{n}$ is observed, and the corresponding branching fraction is measured to be $(1.21\pm0.10\pm0.05)\times10^{-3}$, where the first uncertainty is statistical and second systematic. The data sample used in this analysis was collected with the BESIII detector operating at the BEPCII $e^+e^-$ double-ring collider with a center-of-mass energy of 4.178~GeV and an integrated luminosity of 3.19~fb$^{-1}$. The result confirms the previous measurement by the CLEO Collaboration and is of greatly improved precision, which may deepen our understanding of the dynamical enhancement of the W-annihilation topology in the charmed meson decays

Evidence of a resonant structure in the e+e−→π+D0D∗−e^+e^-\to \pi^+D^0D^{*-} cross section between 4.05 and 4.60 GeV

The cross section of the process $e^+e^-\to \pi^+D^0D^{*-}$ for center-of-mass energies from 4.05 to 4.60~GeV is measured precisely using data samples collected with the BESIII detector operating at the BEPCII storage ring. Two enhancements are clearly visible in the cross section around 4.23 and 4.40~GeV. Using several models to describe the dressed cross section yields stable parameters for the first enhancement, which has a mass of 4228.6 \pm 4.1 \pm 6.3 \un{MeV}/c^2 and a width of 77.0 \pm 6.8 \pm 6.3 \un{MeV}, where the first uncertainties are statistical and the second ones are systematic. Our resonant mass is consistent with previous observations of the $Y(4220)$ state and the theoretical prediction of a $D\bar{D}_1(2420)$ molecule. This result is the first observation of $Y(4220)$ associated with an open-charm final state. Fits with three resonance functions with additional $Y(4260)$, $Y(4320)$, $Y(4360)$, $\psi(4415)$, or a new resonance, do not show significant contributions from either of these resonances. The second enhancement is not from a single known resonance. It could contain contributions from $\psi(4415)$ and other resonances, and a detailed amplitude analysis is required to better understand this enhancement

Observation and study of the decay J/ψ→ϕηη′J/\psi\rightarrow\phi\eta\eta'

We report the observation and study of the decay $J/\psi\rightarrow\phi\eta\eta'$ using $1.3\times{10^9}$ $J/\psi$ events collected with the BESIII detector. Its branching fraction, including all possible intermediate states, is measured to be $(2.32\pm0.06\pm0.16)\times{10^{-4}}$. We also report evidence for a structure, denoted as $X$, in the $\phi\eta'$ mass spectrum in the $2.0-2.1$ GeV/$c^2$ region. Using two decay modes of the $\eta'$ meson ($\gamma\pi^+\pi^-$ and $\eta\pi^+\pi^-$), a simultaneous fit to the $\phi\eta'$ mass spectra is performed. Assuming the quantum numbers of the $X$ to be $J^P = 1^-$, its significance is found to be 4.4$\sigma$, with a mass and width of $(2002.1 \pm 27.5 \pm 21.4)$ MeV/$c^2$ and $(129 \pm 17 \pm 9)$ MeV, respectively, and a product branching fraction $\mathcal{B}(J/\psi\rightarrow\eta{}X)\times{}\mathcal{B}(X\rightarrow\phi\eta')=(9.8 \pm 1.2 \pm 1.7)\times10^{-5}$. Alternatively, assuming $J^P = 1^+$, the significance is 3.8$\sigma$, with a mass and width of $(2062.8 \pm 13.1 \pm 7.2)$ MeV/$c^2$ and $(177 \pm 36 \pm 35)$ MeV, respectively, and a product branching fraction $\mathcal{B}(J/\psi\rightarrow\eta{}X)\times{}\mathcal{B}(X\rightarrow\phi\eta')=(9.6 \pm 1.4 \pm 2.0)\times10^{-5}$. The angular distribution of $J/\psi\rightarrow\eta{}X$ is studied and the two $J^P$ assumptions of the $X$ cannot be clearly distinguished due to the limited statistics. In all measurements the first uncertainties are statistical and the second systematic.Comment: 10 pages, 6 figures and 4 table

Search for the decay J/ψ→γ+invisibleJ/\psi\to\gamma + \rm {invisible}

We search for $J/\psi$ radiative decays into a weakly interacting neutral particle, namely an invisible particle, using the $J/\psi$ produced through the process $\psi(3686)\to\pi^+\pi^-J/\psi$ in a data sample of $(448.1\pm2.9)\times 10^6$ $\psi(3686)$ decays collected by the BESIII detector at BEPCII. No significant signal is observed. Using a modified frequentist method, upper limits on the branching fractions are set under different assumptions of invisible particle masses up to 1.2 $\mathrm{\ Ge\kern -0.1em V}/c^2$. The upper limit corresponding to an invisible particle with zero mass is 7.0$\times 10^{-7}$ at the 90\% confidence level