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Two new sandwich-type heterometallic ZnII-LnIII clusters based on a methoxy substituted salicylamide Salen-like ligand, [Zn2Er3(HL)2(H2L)2(OH)2(NO3)3](NO3)2·2CH3OH (Zn2Er3), [Zn2Yb3(HL)2(H2L)2(OH)2 (NO3)3](NO3)2·2CH3OH (Zn2Yb3), H3L = 1-(2-hydroxy-4-methoxy-benzamido)-2-(2-hydroxy-3-methoxy-benzylideneamino)-ethane, were prepared and structurally characterized. Single-crystal structure analyses reveal that both compounds are pentanuclear clusters with a hydroxyl bridged trinuclear LnIII3 core swaddled by two ZnII ions, two singly deprotoned H2L− ligands, two doubly deprotoned HL− ligands and three nitrate anions. Photophysical determination indicates that the two ZnII-LnIII compounds display both ligand-centered and near-infrared emission. The magnetic susceptibility measurements reveal that Zn2Er3 displays antiferromagnetic interactions with zero field slow magnetization relaxation diagnostic of single-molecule-magnet (SMM).

Here we report five cases of NDM-7-producing Escherichia coli from patients with bacteriuria in a teaching hospital in mainland China. Two isolates belonged to sequence type 131 (ST131), simultaneously carrying blaCTX-M-15, blaSHV-11, blaTEM-1 and qnrS1. The blaNDM-7 gene was located on a conjugative IncX3-type plasmid bearing blaTEM-1 and qnrS1. These findings indicate the spread of NDM-7 metallo-β-lactamase in a highly resistant and virulent E. coli sequence type in China.

Four new polynuclear complexes based on a versatile asymmetric ligand, [Cu 2 (H 2 L) 2 Cl 2 ] ( 1 ), [Cu 4 (H 2 L) 2 (L) 2 ]·4CH 3 OH ( 2 ), [MnL] n ( 3 ), [Er 2 (HL) 2 (NO 3 ) 4 ]·4CH 3 CN ( 4 ), H 3 L = 2-hydroxy-N-(2-((2-hydroxybenzylidene)amino)ethyl)benzamide], were prepared and structurally characterized. The coordination behavior as well as deprotonation of the H 3 L in the four complexes reveal considerable variations depending on the metal ions as well as counter anion. The hydroxyl-bridged dinuclear complex 1 with a Cu–O–Cu–O four-membered ring was obtained when copper chloride was used as metal source. The tetranuclear complex 2 with two Cu–O–Cu–O four-membered rings which bridged both through hydroxy and amide group was obtained using copper acetate instead. Reacting the ligand with manganese acetate yielded complex 3 which exhibits 1-D zig–zag chains only bridged through amide group. While complex 4 which holds a dinuclear one by aid of hydroxyl-bridge without nitrogen atom participating in coordination when erbium nitrate was introduced. The experimental magnetic susceptibilities indicate 1 , 2 and 4 exhibit antiferromagnetic interactions through hydroxy bridge, while 3 exhibits dominant antiferromagnetic interactions with spin canting through the amido bridge.

A new pentadentate chelate-bridging ligand possessing an inner N 2 O 3 coordination site with one amide, one imine, and two phenoxo functions, 2-hydroxy-N-(2-(((3-hydroxynaphthalen-2-yl)methylene)amino)ethyl)benzamide (H 3 L), was synthesised. Reaction it with Mn(OAc) 2 ·4H 2 O yielded a novel zigzag penta-coordinated Mn(III) coordination polymer, [MnL] n , due to the bridging ability of the amide function. The crystal structure of [MnL] n has been determined at 293 K which crystallizes in the monoclinic space group P2 1 /c (No. 14): a = 16.0601(12) A, b = 8.4048(6) A, c = 12.7168(10) A, β = 112.395(9), V = 1606.0(2) A 3 , Z = 4. The experimental magnetic susceptibilities indicates the Mn(III) coordination polymer exhibits dominant antiferromagnetic interactions between the manganese centers through the amido bridge, and spin canting is observed with a ferromagnetic transition occurring at 8.5 K.

Two new structure-related pyrazolone-type Salen ligands, N,N′-ethylamine bis[1-(4-methoxy-phenyl)-3-methyl-4-benzoylimino-2-pyrazoline-5-ol](H2LI) and N,N′-ethylamine bis[1-(4-methoxy-phenyl)-3-methyl-4-acetylimino-2-pyrazoline-5-ol](H2LII) have been designed and synthesized with the ultimate aim of self-assembling novel Zn(II) compounds with interesting fluorescence properties. Reactions of Zn(OAc)2 with the two ligands led to the formation of two new Zn(II) complexes with the formulae of [ZnLI(CH3OH)] (1) and [Zn2LII2] (2), which have been characterized by single-crystal X-ray diffraction, powder X-ray diffraction, elemental analysis, IR spectroscopy and thermal gravimetric analysis. Mononuclear complex 1 with the pentacoordinated zinc(II) ion hosted into the N2O3 compartment crystallized in the monoclinic space group P21/c, while the hydroxyl-bridged dinuclear [Zn2LII2] complex (2) with the pentacoordinated zinc(II) ion hosted into the N2O2 compartment crystallized in the monoclinic space group C2/c and had a Zn–O–Zn–O four-membered ring. The structure determinations show that substituted group at the 4,4′-position of the this kind of Salen ligands are important factors influencing the crystalline array. The fluorescent properties of the two compounds at ambient temperature both in solid state and solution were also investigated. The results provided interesting insights into ligand effects on the structures and fluorescent properties of zinc(II) coordination complexes.

The stepwise course of the synthesis of ZnIILnIII complexes of a new compartmental heptadentate open amide crown ether ligand has been investigated through the determination of the intermediate and final products occurring in the process. In the first step, the ligand L is reacted with Ln(NO3)3·5H2O to give the electroneutral complex [LnIIIL(NO3)3] with the lanthanide ion being linked to the N3O2 coordination site of the ligand which are fairly stable and could be isolated. Addition of Zn(NO3)3·6H2O to the [LnIIIL(NO3)3] complexes yield the desired heterodinuclear [ZnIILnIIIL(NO3)5(H2O)] complexes. In all [ZnIILnIIIL(NO3)5(H2O)] complexes, the ZnII ions invariably occupy the N3O2 site whereas the LnIII ions show preference for the carbonyl O site. Additionally, the solid-state photophysical properties of these complexes show that the sensitized EuIII- and TbIII-based luminescence can be enhanced after ZnII ion is incorporated.

An improved level set evolution model is proposed to segment the ultrasound images accurately and efficiently in this paper. At first, the multi-scale gradient vector field is employed to reduce the image noise. We assign the standard deviation as a scale to set up several scales images, and use the gradient direction information between the adjacent scales to refine the multi-scale gradient vector field, which highlights the real boundaries and reduces the noise. Besides, the divergence operator of the multi-scale gradient vector field is used to overcome the sensitivity problem of initialization and avoid boundary leakage. The experiments results demonstrate that the performance of the proposed method is very close to the ground truths obtained from manual segmentation by specialists with higher area similarity measure (ASM) and lower mean contour distance (MCD), which demonstrated that the proposed method is reliable, accurate and robust for the tumor boundary segmentation in ultrasound images.

A new three-dimensional framework iodide, (DabcoH)2[(Dabco)2Ag14I16] (1), was solvothermal synthesized by transformation of dense AgI using p-methylthiophenol as mineralizer, and characterized by elemental analysis, single-crystal and powder X-ray diffraction, thermogravimetric analysis, differential scanning calorimetry analysis, UV–vis diffuse reflectance spectroscopy and fluorescence spectroscopy. Compound 1 crystallizes in the trigonal space group R-3c, a=13.4452(2) A, c=63.725(2) A, V=9976.5(4) A3, Z=6. It features a 3D silver-rich [(Dabco)2Ag14I16]2− anionic framework built up from corner-sharing of hybrid [(Dabco)2Ag14I19]5− clusters, with protonated DabcoH+ as counterions residing in the channels. UV–vis reflectance spectroscopy reveals the band gap of 1 is 3.3 eV. Compound 1 exhibits a strong photoluminescent emission band at 567 nm upon excitation at 489 nm.