Investigation of molecular states with charm and beauty hadrons

La Fisica de hadrones ha tenido un desarrollo espectacular en los ultimos años debido a la pletora de estados nuevos que han sido descubiertos en laboratorios como BES en Beijing, la colaboracion Babar en USA, Belle en Japon, CLEO en USA y el CERN en Europa, entre otros. El modelo de quarks, segun el cual los mesones estan formados de quark antiquark y los bariones de tres quarks, tuvo en su dia un valor incalculable, al permitir entender los hadrones en terminos de unos pocos componentes elementales. Las predicciones que hizo, y fueron confirmadas, puso este modelo de los hadrones en un lugar incuestionable de la Historia de la Fisica. Sin embargo, el paso del tiempo nos ha ido enseñando que la Naturaleza es mas sutil que nuestros modelos y una una parte de los estados observados recientemente no pueden explicarse en los terminos convencionales y exigen estructuras mas complejas.In our work, we have made some investigations on the hadronic spectrum, mostly in the heavy quark sector, focusing mainly on the baryonic states with charm and beauty. Besides, we also did some works on the mesonic states both in the light and the heavy quark sectors. First, we explore the recently developed three-body interaction formalism, the fix center approximation to the Faddeev equations, to study some strong interaction of the three-body hadronic systems. Second, we investigate the two-body interactions in the charm and beauty sector with the coupled channel approach, by taking into account the constraints of heavy quark spin symmetry. Third, we study the decay models and properties of some resonances, theoretically predicted in the strong interactions of low energy QCD

Effects of the interplay between fermionic interactions and disorders in the nodal-line superconductors

We study the interplay between fermion-fermion interactions and disorder scatterings beneath the superconducting dome of noncentrosymmetric nodal-line superconductors. With the application of renormalization group, several interesting low-energy behaviors are extracted from the coupled equations of all interaction parameters. At the clean limit, fermion-fermion interactions decrease with lowering the energy scales but conversely fermion velocities climb up and approach certain saturated values. This yields a slight decrease or increase of the anisotropy of fermion velocities depending upon their initial ratio. After bringing out four kinds of disorders designated by the random charge ($\Delta_{1}$), random mass ($\Delta_{2}$), random axial chemical potential ($\Delta_{3}$), and spin-orbit scatterers ($\Delta_{4}$) based on their own unique features, we begin with presenting the distinct low-energy fates of these disorders. For the presence of sole disorder, its strength becomes either relevant ($\Delta_{1,4}$) or irrelevant($\Delta_{2,3}$) in the low-energy regime. However, the competition for multiple sorts of disorders is capable of qualitatively reshaping the low-energy properties of disorders $\Delta_{2,3,4}$. Besides, it can generate an initially absent disorder as long as two of $\Delta_{1,2,3}$ are present. In addition, the fermion-fermion couplings are insensitive to the presence of $\Delta_4$ but rather substantially modified by $\Delta_1$, $\Delta_2$, or $\Delta_3$, and evolve towards zero or certain finite non-zero values under the coexistence of distinct disorders. Furthermore, the fermion velocities flow towards certain finite saturated value for the only presence of $\Delta_{2,3}$ and vanish for all other situations. As to their ratio, it acquires a little increase once the disorder is subordinate to fermionic interactions, otherwise keeps some fixed constant.Comment: 22 pages, 25 figures (accepted by European Physical Journal Plus

2-Carb­oxy-1-phenyl­ethanaminium nitrate

In the title salt, C9H12NO2 +·NO3 −, the cation and anion are linked by a bifurcated N—H⋯(O,O) hydrogen bond. The crystal packing is stabilized by inter­molecular N—H⋯O, O—H⋯O and C—H⋯O hydrogen bonds, which connect neighbouring cations and anions, resulting in a two-dimensional network

Flavonoids with α-glucosidase inhibitory activities and their contents in the leaves of Morus atropurpurea

BACKGROUND: This study aims to isolate the α-glucosidase inhibitory compounds from mulberry leaves (Morus atropurpurea Roxb., Moraceae) and to develop an analytical method for quantification of the compounds. METHODS: Four flavonoids, rutin (1), isoquercetin (2), kaempferol-3-O-rutinoside (3) and astragalin (4), were isolated by column chromatography from mulberry leaf water extracts (MWE). The α-glucosidase inhibitory activities of MWE and the four isolated compounds were evaluated by a microplate-based in vitro assay. The content of the isolated flavonoids in M. atropurpurea leaves purchased from different local herbal stores or collected in different locations was determined by high performance liquid chromatography. RESULTS: The four flavonoids (1–4) showed α-glucosidase inhibitory activities, with rutin (1) and astragalin (4) showing high α-glucosidase inhibitory activities (IC(50) values of 13.19 ± 1.10 and 15.82 ± 1.11 μM, respectively). The total contents of the four flavonoids were different among eight samples examined, ranging from 4.34 mg/g to 0.53 mg/g. CONCLUSIONS: The four flavonoids in M. atropurpurea leaves could inhibit α-glucosidase activity

STAR-RIS-Assisted-Full-Duplex Jamming Design for Secure Wireless Communications System

Physical layer security (PLS) technologies are expected to play an important role in the next-generation wireless networks, by providing secure communication to protect critical and sensitive information from illegitimate devices. In this paper, we propose a novel secure communication scheme where the legitimate receiver use full-duplex (FD) technology to transmit jamming signals with the assistance of simultaneous transmitting and reflecting reconfigurable intelligent surface (STARRIS) which can operate under the energy splitting (ES) model and the mode switching (MS) model, to interfere with the undesired reception by the eavesdropper. We aim to maximize the secrecy capacity by jointly optimizing the FD beamforming vectors, amplitudes and phase shift coefficients for the ESRIS, and mode selection and phase shift coefficients for the MS-RIS. With above optimization, the proposed scheme can concentrate the jamming signals on the eavesdropper while simultaneously eliminating the self-interference (SI) in the desired receiver. To tackle the coupling effect of multiple variables, we propose an alternating optimization algorithm to solve the problem iteratively. Furthermore, we handle the non-convexity of the problem by the the successive convex approximation (SCA) scheme for the beamforming optimizations, amplitudes and phase shifts optimizations for the ES-RIS, as well as the phase shifts optimizations for the MS-RIS. In addition, we adopt a semi-definite relaxation (SDR) and Gaussian randomization process to overcome the difficulty introduced by the binary nature of mode optimization of the MS-RIS. Simulation results validate the performance of our proposed schemes as well as the efficacy of adapting both two types of STAR-RISs in enhancing secure communications when compared to the traditional selfinterference cancellation technology.Comment: 12 pages, 7 figure

Poly[[diaqua­[μ4-4,4′-carbonyl­bis(benzene-1,2-dicarboxyl­ato)]bis­(dipyrido[3,2-a:2′,3′-c]phenazine)dicadmium(II)] monohydrate]

In the title compound, {[Cd2(C17H6O9)(C18H10N4)2(H2O)2]·H2O}n, the CdII atom is seven-coordinated by five O atoms from two different 4,4′-carbonyl­bis(benzene-1,2-dicarboxyl­ate) (BPTC) anions and one water mol­ecule, and by two N atoms from one chelating dipyrido[3,2-a:2′,3′-c]phenazine (L) ligand in a distorted penta­gonal-bipyramidal geometry. The BPTC anions link the CdII atoms, forming a one-dimensional chain structure. The L ligands are attached on both sides of the chain. A twofold rotation axis passes through the complex molecule. The crystal structure involves O—H⋯O hydrogen bonds

Narrow Bound States of the DNN System

We report on a recent calculation of the properties of the DNN system, a charmed meson with two nucleons. The system is analogous to the system substituting a strange quark by a charm quark. Two different methods are used to evaluate the binding and width, the Fixed Center approximation to the Faddeev equations and a variational calculation. In both methods we find that the system is bound by about 200 MeV and the width is smaller than 40 MeV, a situation opposite to the one of the system and which makes this state well suited for experimental observation