Zc(3900)Z_c(3900) as a DDˉ∗D\bar{D}^* molecule from the pole counting rule

A comprehensive study on the nature of the $Z_c(3900)$ resonant structure is carried out in this work. By constructing the pertinent effective Lagrangians and considering the important final-state-interaction effects, we first give a unified description to all the relevant experimental data available, including the $J/\psi\pi$ and $\pi\pi$ invariant mass distributions from the $e^+e^-\to J/\psi\pi\pi$ process, the $h_c\pi$ distribution from $e^+e^-\to h_c\pi\pi$ and also the $D\bar D^{*}$ spectrum in the $e^+e^-\to D\bar D^{*}\pi$ process. After fitting the unknown parameters to the previous data, we search the pole in the complex energy plane and find only one pole in the nearby energy region in different Riemann sheets. Therefore we conclude that $Z_c(3900)$ is of $D\bar D^*$ molecular nature, according to the pole counting rule method~[Nucl.~Phys.~A543, 632 (1992); Phys.~Rev.~D 35,~1633 (1987)]. We emphasize that the conclusion based upon the pole counting method is not trivial, since both the $D\bar D^{*}$ contact interactions and the explicit $Z_c$ exchanges are introduced in our analyses and they lead to the same conclusion.Comment: 21 pages, 9 figures. To match the published version in PRD. Additional discussion on the spectral density function is include

A novel myocardium segmentation approach based on neutrosophic active contour model

Automatic delineation of the myocardium in echocardiography can assist ra- diologists to diagnosis heart problems. However, it is still challenging to distinguish myocardium from other tissue due to a low signal-to-noise ratio, low contrast, vague boundary, and speckle noise

A framework to design interaction control of aerial slung load systems: transfer from existing flight control of under-actuated aerial vehicles

This paper establishes a framework within which interaction control is designed for the aerial slung load system composed of an underactuated aerial vehicle, a cable and a load. Instead of developing a new control law for the system, we propose the interaction control scheme by the controllers for under-actuated aerial systems. By selecting the deferentially flat output as the configuration, the equations of motion of the two systems are described in an identical form. The flight control task of the under-actuated aerial vehicle is thus converted into the control of the aerial slung load system. With the help of an admittance filter, the compliant trajectory is generated for the load subject to external interaction force. Moreover, the convergence of the whole system is proved by using the boundedness of the tracking error of vehicle attitude tracking as well as the estimation error of external force. Based on the developed theoretical results, an example is provided to illustrate the design algorithm of interaction controller for the aerial slung load via an existing flight controller directly. The correctness and applicability of the obtained results are demonstrated via the illustrative numerical example

Occupational exposure to silica dust and risk of lung cancer: an updated meta-analysis of epidemiological studies

Funnel plot for studies with odds ratio (OR) as measure of association. (DOC 144 kb

Identification of metabolites of kurarinone from Sophora flavescens Ait in rat urine by ultra-performance liquid chromatography with linear ion trap orbitrap mass spectrometry

Purpose: To study the in vivo metabolism of kurarinone, a lavandulyl flavanone which is a major constituent of Kushen and a marker compound with many biological activities, using ultra-performance liquid chromatography coupled with linear ion trap Orbitrap mass spectrometry (UPLC-LTQ-Orbitrap-MS).Methods: Six male Sprague-Dawley rats were randomly divided into two groups. First, kurarinone was suspended in 0.5 % carboxymethylcellulose sodium  (CMC-Na) aqueous solution, and was given to rats (n = 3, 2 mL for each rat) orally at 50 mg/kg. A 2 mL aliquot of 0.5 % CMC-Na aqueous solution was administered to the rats in the control group. Next, urine samples were collected over 0-24 h after the oral administrations and all urine samples were pretreated by a solid phase extraction (SPE) method. Finally, all samples were analyzed by a UPLC-LTQ-Orbitrap mass spectrometry coupled with an electrospray ionization source (ESI) that was operated in the negative ionization mode.Results: A total of 11 metabolites, including the parent drug and 10 phase II metabolites in rat urine, were first detected and interpreted based on accurate mass measurement, fragment ions, and chromatographic retention times. The results were based on the assumption that kurarinone glucuronidation was the dominant  metabolite that was excreted in rat urine.Conclusion: The results from this work indicate that kurarinone in vivo is typically transformed to nontoxic glucuronidation metabolites, and these findings may help to characterize the metabolic profile of kurarinone.Keywords: Kurarinone, Metabolites, Sophora flavescens Ait., Glucuronidation metabolite

Combined effect of Cu- and ZnO- NPs on antibiotic resistance genes in an estuarine water

Most studies of whether and how nanoparticles (NPs) affect antibiotic resistance genes (ARGs) focus on testing single NPs type. In this study, we determined the combined effect of Cu- and ZnO- NPs in the water samples collected from the Yangtze River Estuary and found the effect differs greatly from that produced by individual NPs. The results showed that the Cu- and ZnO- NPs co-exposure resulted in an enrichment of ARGs, whereas individual Cu- and ZnO- NPs exposure decreased the abundance of ARGs. Furthermore, the co-exposure of Cu- and ZnO- NPs induced obvious changes in the microbial communities compared to the control communities. Redundancy analysis suggested that the microbial community contributed the most (43.5%) to the ARG profiles, followed by dissolved metal ions (25.7%), MRGs, (19.4%), and MGEs (4.4%). Network analysis found several potential hosts (such as Mycobacterium and Escherichia coli) and implied the extent of the risk of ARG transmission into various environmental niches by these common microbes