No evidence for the evolution of mass density power-law index γ\gamma from strong gravitational lensing observation

In this paper, we consider the singular isothermal sphere lensing model that has a spherically symmetric power-law mass distribution $\rho_{tot}(r)\sim r^{-\gamma}$. We investigate whether the mass density power-law index $\gamma$ is cosmologically evolutionary by using the strong gravitational lensing (SGL) observation, in combination with other cosmological observations. We also check whether the constraint result of $\gamma$ is affected by the cosmological model, by considering several simple dynamical dark energy models. We find that the constraint on $\gamma$ is mainly decided by the SGL observation and independent of the cosmological model, and we find no evidence for the evolution of $\gamma$ from the SGL observation.Comment: 7 pages, 3 figure

catena-Poly[potassium-di-μ-aqua-μ-4-(5-tetra­zolio)pyridine]

The title compound, [K(C6H4N5)(H2O)2]n, was synthesized by hydro­thermal reaction of KOH with 4-(5-tetra­zolio)pyridine. The K atom has a distorted octa­hedral coordination environment and is coordinated by two axial N atoms from the organic ligand and by four water mol­ecules in the equatorial plane. The mol­ecules as a whole are located on crystallographic mirror planes; the K atom is also located on an inversion center. Both the water mol­ecules and the organic ligands act as bridges to link symmetrically the adjacent K atoms into polymeric chains parallel to the c axis. O—H⋯N hydrogen bonds involving the water O atoms and aromatic π–π inter­actions [centroid–centroid distance 3.80 (2) Å] between the pyridine and tetra­zole rings build up an infinite three-dimensional network

根据医学特点，开展临床研究生思想政治教育

Along with the reform of medical system, medical education in China is also undergoing great changes. Due to the special characteristics of medical education, it differs from other educational characteristics. It carries with the characteristics of clinical practice on the basis distributed learning, physical and mental development along with ages, enrollment expansion and medical requirement, and standardization training for resident doctors. So, ideological and political education of clinical graduates showed many new characteristics. First, medical ethics education is the basic step, combined with the related disciplines of medical humanity connotation. Second, flexible and diversified form of ideological and political education on the basis of medical work is necessary. Third, establish a system of ideological and political education for clinical graduates, to build up new education concept, and to develop ideological and political education activities for clinical graduates in depth.随着医疗体制改革的推进，医学教育也在不断摸索中前进，因为医学教育的特殊性，使它具备不同于其它学科的教育特点。临床实践为主分散式学习，年龄与身心发展的新特点，扩招和医学实现的发展需要，与住院医师规范化培训统一等等特点，使现代临床医学研究生的思想政治教育呈现许多新的特点。根据临床医学研究生的各种特殊性开展思想政治教育，首先在内容上应以医德医风教育为主，结合医学人文相关学科的思想内涵进行。其次在形式上要结合医疗工作实际开展灵活多样、形式新颖的思想政治教育。最后要建立一个适应临床研究生思想政治教育的体系，形成教育模式，建立全新的教育理念，全面进行临床医学研究生思想政治教育活动

4,5-Diphenyl-2-p-tolyl-1H-imidazol-3-ium nitrate

In the cation of the title compound, C22H19N2 +·NO3 −, the N atom in the 3-position of the imidazole is protonated. The three pendant aromatic rings are twisted from the plane of the imadazolium ring by dihedral angles of 38.1 (1), 43.74 (9) and 20.4 (1)°. In the crystal structure, N—H⋯O and N—H⋯(O,O) hydrogen bonds link the mol­ecules to form an infinite one-dimensional chain parallel to the c axis

A closer look at interacting dark energy with statefinder hierarchy and growth rate of structure

We investigate the interacting dark energy models by using the diagnostics of statefinder hierarchy and growth rate of structure. We wish to explore the deviations from $\Lambda$CDM and to differentiate possible degeneracies in the interacting dark energy models with the geometrical and structure growth diagnostics. We consider two interacting forms for the models, i.e., $Q_1=\beta H\rho_c$ and $Q_2=\beta H\rho_{de}$, with $\beta$ being the dimensionless coupling parameter. Our focus is the I$\Lambda$CDM model that is a one-parameter extension to $\Lambda$CDM by considering a direct coupling between the vacuum energy ($\Lambda$) and cold dark matter (CDM), with the only additional parameter $\beta$. But we begin with a more general case by considering the I$w$CDM model in which dark energy has a constant $w$ (equation-of-state parameter). For calculating the growth rate of structure, we employ the "parametrized post-Friedmann" theoretical framework for interacting dark energy to numerically obtain the $\epsilon(z)$ values for the models. We show that in both geometrical and structural diagnostics the impact of $w$ is much stronger than that of $\beta$ in the I$w$CDM model. We thus wish to have a closer look at the I$\Lambda$CDM model by combining the geometrical and structural diagnostics. We find that the evolutionary trajectories in the $S^{(1)}_3$--$\epsilon$ plane exhibit distinctive features and the departures from $\Lambda$CDM could be well evaluated, theoretically, indicating that the composite null diagnostic $\{S^{(1)}_3, \epsilon\}$ is a promising tool for investigating the interacting dark energy models.Comment: 17 pages, 4 figures; accepted for publication in JCA