A novel mixed alkali hydro-isocyanurate, KLi­(HC3N3O3)·2H2O was first prepared in AOH-BOH-H3C3N3O3 (A/B = Li/Na/K/Rb/Cs) system via a solvent-drop grinding method. KLi­(HC3N3O3)·2H2O shows a large second harmonic generation response (5.3 × KH2PO4) with an ultraviolet cutoff edge of 237 nm. More importantly, the bulk single crystal can be readily grown through water solution technique. Characterization of these crystals indicates that KLi­(HC3N3O3)·2H2O has a high laser damage threshold (LDT) (4.76 GW/cm2) and exhibits a large birefringence (Δn = 0.186@514 nm), which reduces Type I phase-matching to 246 nm.

Since glycopeptide-resistant enterococci (GRE) were reported in 1988, they have appeared in hospitals worldwide. Seven van gene cluster types (vanA, vanB, vanC, vanD, vanE, vanG, and vanL) are currently known. We investigated a clinical strain of Enterococcus faecium Efm-HS0661 that was isolated in 2006 from an inpatient with intra-abdominal infection in Shanghai. It was resistant to most antimicrobials, including vancomycin (MIC, >256 g/ml) and teicoplanin (MIC, 96 g/ml). Glycopeptide resistance could be transferred to E. faecium BM4105RF by conjugation. The donor and its transconjugant were negative by PCR for the known van genes. By cloning and primer walk sequencing, we discovered a novel van gene cluster, designated

A new tin iodate fluoride, Sn­(IO3)2F2, was meticulously designed based on Sn­(IO3)4 with an intriguing chemical tailoring transformation from the centrosymmetric to noncentrosymmetric structure. Sn­(IO3)2F2 crystallizes in polar space group P21 and features an one-dimensional chain constructed by IO3 and SnO4F2. It has an enlarged band gap (4.08 eV) compared to the Sn­(IO3)4 (3.96 eV) because of the introduction of strong electronegative F–. Also, powder second-harmonic generation (SHG) measurements revealed that Sn­(IO3)2F2 is a phase-matchable nonlinear crystal with a strong SHG response about 3 times that of KH2PO4. Theoretical investigations elaborated that its large nonlinearity originates from the synergistic effect of lone pairs on IO3 and flexible dipole moments of SnO4F2 polyhedra.

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Pterygium affects approximately one-ninth of Han and Uygur population. Compared with Uygur, Han ethnicity is a significant risk factor of pterygium. Our results indicated a higher prevalence of pterygium in rural areas of Xinjiang, China compared with urban cities. Age increase was also associated with presence of pterygium. Strategies are warranted to prevent the serious effects caused by pterygium.

A new hydro-isocyanurate, RbNa(HC3N3O3)·2H2O, with a strong SHG response and large birefringence, has been successfully grown by a hydrothermal method.

The first fluorosulfonic ultraviolet (UV) nonlinear optical (NLO) material, C(NH2)3SO3F, is rationally designed by taking KBe2BO3F2 (KBBF) as the parent compound. C(NH2)3SO3F features similar topological layers as KBBF by replacing inorganic (BO3)3− with organic C(NH2)3+ trigonal units and BeO3F with SO3F− tetrahedra. Therefore, C(NH2)3SO3F is a metal‐free UV NLO crystal. Benefiting from the coplanar configuration of the C(NH2)3+ cationic groups, it possesses a large SHG response of 5×KDP and moderate birefringence of 0.133@1064 nm. Besides, it has a short UV cutoff edge of 200 nm. The calculated results reveal the shortest SHG phase‐matching wavelengths can reach 200 nm. These findings highlight the exploration of metal‐free compounds as nontoxic and low‐cost UV NLO materials as a new research area.

The first alkali-metal nitrate isocyanurates, A­(H3C3N3O3)­(NO3) (A = K, Rb), were synthesized by the tactic of introducing (NO3)− into isocyanurate with a mild hydrothermal technique. They crystallized into the same monoclinic centrosymmetric (CS) space group P21/c, which featured a 2D [(H3C3N3O3)­(NO3)]∞ layered structure separated by K+ and Rb+ cations, respectively. Both compounds exhibited short ultraviolet cutoff edges (λcutoff = 228 and 229 nm) and large birefringences (Δn = 0.253 and 0.224 at 546.1 nm). More importantly, in comparison with most of the isocyanurates and nitrates, they have better thermal stability with decomposition temperatures up to 319.8 and 324.4 °C. In addition, our theoretical calculations reveal that the π-conjugated groups play significant roles in improving the optical anisotropy. Remarkably, introducing a π-conjugated inorganic acid radical (NO3)− into isocyanurate is an extremely meaningful strategy to explore new UV birefringent crystals.