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Despite extensive experimental and theoretical studies, the atomistic mechanisms responsible for dielectric breakdown (BD) in amorphous (a)-SiO2 are still poorly understood. A number of qualitative physical models and mathematical formulations have been proposed over the years to explain experimentally observable statistical trends. However, these models do not provide clear insight into the physical origins of the BD process. Here, we investigate the physical mechanisms responsible for dielectric breakdown in a-SiO2 using a multi-scale approach where the energetic parameters derived from a microscopic mechanism are used to predict the macroscopic degradation parameters of BD, i.e., time-dependent dielectric breakdown (TDDB) statistics, and its voltage dependence. Using this modeling framework, we demonstrate that trapping of two electrons at intrinsic structural precursors in a-SiO2 is responsible for a significant reduction of the activation energy for Si-O bond breaking. This results in a lower barrier for the formation of O vacancies and allows us to explain quantitatively the TDDB data reported in the literature for relatively thin (3-9 nm) a-SiO2 oxide films. [ABSTRACT FROM AUTHOR]

The anti-metastasis effect of oridonin in combination with oxaliplatin on colorectal cancer liver metastasis was studied using a BALB/c nude mouse model. The liver condition, bloody ascites, cholestasis, and liver metastasis scores in the three groups receiving oxaliplatin combined with oridonin were significantly milder than in the control group and importantly the anti-migratory effect of oxaliplatin combined with oridonin was obviously the strongest (p<0.05). Oridonin possessed no hepatotoxicity; instead, it effectively alleviated liver injury caused by oxaliplatin. Oridonin alone or in combination with oxaliplatin significantly decreased serum levels of α-fetoprotein and carcinoembryonic antigen. Therefore, oridonin combined with oxaliplatin displays great potential to markedly increase the anti-metastasis effect of oxaliplatin in the treatment of liver metastases of colorectal cancer. [ABSTRACT FROM AUTHOR]

Solvothermal condition reaction of Ln(NO3)3 ⋅ 6H2O (Ln = Er, Eu) with 5-nitroisophthalate (Nipt2–) and mononuclear macrocyclic oxamide complex ML (M = Ni or Cu) afforded two new 3d–4f heterometallic coordination polymers [Er2(CuL)2(Nipt)3(H2O)] ⋅ 0.75H2O (I) and [Eu2(NiL)2(Nipt)3(H2O)] ⋅ H2O (II) (ML, H2L = 2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-dien; H2Nipt = 5-nitroisophthalic acid). Their structures have been characterized by elemental analyses, FT-IR, UV, and single-crystal X-ray diffraction analyses (CIF files CCDC nos. 1880429 (I), 1880430 (II)). Both complexes I and II exhibit a 2D dimensional heterometallic framework with 3,3,4,5-connected (3.4.5)(32.42.5.63.72)(42.63.8)(42.6) topology, and adjacent 2D structures are connect together with intermolecular O–H⋅⋅⋅O and C–H⋅⋅⋅O hydrogen bonds to form a 3D superamolecular architectures. Moreover, the visible and near-infrared luminescence properties of the compound I are also discussed. [ABSTRACT FROM AUTHOR]

Abstract: Two novel 3d-4f coordination polymers [Ln(NiL)(Nipt)(C2O4)0.5 · H2O] · H2O (Ln = Er (I), Eu (II) (H2L = 2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclopentadeca-7,13-dien; H2Nip = 5-nit-roisophthalic acid) were obtained by using 5-nitroisophthalate and mononuclear macrocyclic oxamide complex NiL as co-ligand to react with Ln(NO3)3 ⋅ 6H2O (Ln = Er, Eu) under solvothermal condition, and characterized by single crystal X-ray diffraction (CIF files CCDC nos. 1587618 (I) and 1587619 (II)). Two complexes are isostructural structure and exhibit a two-dimensional network architecture formed by [Ln(III)Ni(II)] units via the oxamide, 5-nitroisophthalate and oxalate bridges, and adjacent 2D structures are linked together with C-H⋅⋅⋅O and O-H⋅⋅⋅O intermolecular hydrogen bonds to form a 3D superamolecular architectures. The fluorescence properties of I and II are also characterized. [ABSTRACT FROM AUTHOR]

The prevalence of Clonorchis sinensis infection in freshwater fishes was surveyed in Heilongjiang Province, northeastern China, between August 2011 and September 2013. Thirteen species of freshwater fish (n = 3221) and one species of shrimp (n = 93) were collected from Songhua river, Nenjiang river and other lakes or ponds in 37 sites of 15 representative cities in Heilongjiang Province. They were individually examined by digestion technique, and the C. sinensis metacercariae were identified morphologically followed by confirmation using sequences of the second internal transcribed spacer of ribosomal DNA. Ten of the 13 examined species of freshwater fishes were infected with C. sinensis metacercariae, while all shrimps were negative. The overall prevalence of C. sinensis infection in 3221 examined freshwater fishes was 19.96%, with 42.57% (272/639) in Pseudorasbora parva, 22.55% (83/368) in Hemicculter leuciclus, 20.44% (121/592) in Carassius auratus, 17.71% (68/384) in Saurogobio dabryi, 10.85% (23/212) in Rhodeus ocellatus, 10.54% (48/455) in Phoxinus lagowskii, 8.20% (21/256) in Perccottus glehnii, 6.25% (5/80) in Misgurnus anguillicaudatus, 4.55% (1/22) in Xenocypris davidi, and 1.49% (1/67) in Cyprinus carpio. The average infection intensity in P. parva was 103.3 encysted metacercariae per gram of fish meat in Zhaoyuan city. The average prevalence of C. sinensis infection in Songhua river, Nenjiang river and lakes or ponds were 31.96% (503/1574), 11.30% (102/903) and 7.93% (59/744), respectively. The prevalence of C. sinensis infection in Zhaoyuan city (43.68%) was the highest among all sampling locations. These results revealed a high-prevalence of C. sinensis infection in freshwater fishes in Heilongjiang Province, northeastern China, posing significant public health concern. [ABSTRACT FROM AUTHOR]

One novel heterometallic trinuclear complex of macrocyclic oxamide [Ni(CuL) 2(HBTC)H 2O] ( I) (H 2L = 2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclopentadeca-7,13-dien; H 3BTC = 1,3,5-benzenetricarboxylic acid) has been solvothermally synthesized and structurally characterized by elemental analysis, IR spectroscopy, XRD, and single-crystal X-ray diffraction. The crystals crystallize in the monoclinic system, space group P2 1/ c, a = 11.435(3), b = 20.646(5), c = 18.430(5) Å, β = 94.131(4)°. The structure of I has oxamido-bridged trinuclear [Cu 2IINi II] units and consists of two-dimensional supramolecular architecture formed by strong intermolecular hydrogen bonds. Furthermore, the magnetic properties of complex I was investigated and discussed in detail. [ABSTRACT FROM AUTHOR]

Macrocyclic and supermolecular complexes [Cu(NiL)Cl] ( I) and [Cd(CuL)Cl] ( II) (HL = 2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-diene) have been synthesized and structurally determined by X-ray diffraction and IR spectrum. Complex I crystallizes in the monoclinic system with P2/ n group, a = 10.9019(15), b = 14.3589(19), c = 12.4748(17) 0A, β = 108.645(2)°, Z = 4. Complex II crystallizes in the monoclinic system with P2/ n group, a = 10.9784(16), b = 14.580(2), c = 12.8904(18) Å, β = 109.339(2)°, Z = 4. [ABSTRACT FROM AUTHOR]

The complex incorporating macrocyclic oxamide of the formula [(CuL)Cd(NCS)] (HL = 2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-diene) has been synthesized and structurally characterized. The crystals crystallize in the monoclinic system, space group C2/ c, a = 13.865(3), b = 14.390(3), c = 38.252(8) Å, β = 92.45(3)°, Z = 8. The crystal structure unit is a trianuclear complex in which the Cd and Cu ions are bridged by the macrocyclic oxamide groups. The [(CuL)Cd(NCS)] units are alternately bridged by C-H···O to C-H···S hydrogen bond to form a 2D framework. The luminescent property of the compound is also discussed. [ABSTRACT FROM AUTHOR]