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A series of unsymmetrical 2-(2,4-bis(bis(4-methoxyphenyl)methyl)-6-MeC6H2N)-6-(1-(arylimino)ethyl)pyridine-iron halides has been synthesized and characterized. The molecular structure of two representative species was determined by the single-crystal X-ray diffraction. Activated with either MAO or MMAO, the precatalysts displayed high activity, reaching 2.19×107 g PE (mol Fe)−1 h−1 at 60 °C in ethylene polymerization. The microstructural analysis of the polymers obtained indicates highly linear polyethylene containing a vinyl chain end.

High activities in ethylene polymerization predetermine α‐diiminonickel precatalysts for potential industrial applications. In our study, we have synthesized and characterized a series of unsymmetrical 1‐(2,4‐bis(4,4′‐dimethoxybenzhydryl)‐6‐MeC6H2N)‐2‐arylimino‐acenaphthylene nickel(II) halides. The single‐crystal X‐ray diffraction study of representative compounds reveals distorted tetrahedral geometry. On activation with either Me2AlCl or modified methylaluminoxane, these nickel complexes exhibit high activities of the order of 106 g of PE (mol of Ni)−1 h−1 and produce polyethylene of generic application characterized by high molecular weight, narrow molecular weight distribution, and moderate degree of branching. The substituents at the ligands affect the catalytic performance of the nickel complexes and tune the microstructure of the resultant polyethylene.

Non-volatile and volatile flavor compounds of six Pleurotus mushrooms including Pleurotus citrinopileatus, P. cornucopiae, P. djamor, P. floridanus, P. ostreatus and P. sapidus were studied.; Results: The content of total free amino acids ranged from 21.80 to 40.60 g kg-1 and the content of monosodium glutamate (MSG)-like amino acids ranged from 3.10 to 8.64 g kg-1 . The content of total 5'-nucleotides ranged from 4.16 to 8.80 g kg-1 while the content of flavor 5'-nucleotides ranged from 2.00 to 4.51 g kg-1 . Sixty-three volatile compounds were identified in six Pleurotus mushrooms, including 17 aldehydes, 10 ketones, 14 alcohols, 2 ethers, 5 acids, 5 hydrocarbons, 10 heterocyclic and aromatic compounds. 1-Octen-3-one and 1-octen-3-ol were the key odor compounds in P. citrinopileatus, P. djamor, P. ostreatus, P. floridanus and P. sapidus, while 1-octen-3-one, 1-octen-3-ol and 2-octenal were the key odor compounds in P. cornucopiae.; Conclusion: Pleurotus citrinopileatus had highest content of total free amino acids (40.60 g kg-1 ), total 5'-nucleotides (8.80 g kg-1 ) and flavor 5'-nucleotides (4.51 g kg-1 ) than other Pleurotus mushrooms. Moreover, eight-carbon compounds were the most abundant compounds in six Pleurotus mushrooms. Our study should be helpful in promoting the cultivation and consumption of these Pleurotus mushrooms. © 2018 Society of Chemical Industry.; © 2018 Society of Chemical Industry.

The alterations of sialylation on cell surface N-glycans due to overexpression of different sialyltransferases play a vital role in tumorigenesis and tumor progression. The β-galactoside α2-6-sialyltransferase 1 (ST6Gal-I) has been reported to be highly expressed in several cancers, including breast cancer, hepatocellular cancer and colon carcinoma. However, the roles and underlying mechanisms of ST6Gal-I in non-small cell lung cancer (NSCLC) still need to be elucidated. In this study, we determined that mRNA levels of ST3GAL1, ST6GALNAC3 and ST8SIA6 were remarkably reduced in lung cancer tissues and cells, whereas ST6GAL1 level significantly increased. The mRNA, protein and glycan levels of ST6Gal-I were higher in lung cancer tissues and cells. Moreover, down-regulation of ST6Gal-I decreased protein levels of Jagged1, DLL-1, Notch1, Hes1, Hey1, matrix-metalloproteinases (MMPs) and VEGF, and suppressed proliferation, migration and invasion capabilities of A549 and H1299 cells in vitro. In vivo, ST6Gal-I silencing suppressed tumorigenicity of NSCLC cells in athymic nude mice via the Notch1/Hes1/MMPs pathway. In addition, overexpression of Notch1 rescued the reduced growth and metastasis of A549 and H1299 cells resulted by ST6Gal-I silencing. Modification of α2,6-sialylation positively associates with lung cancer progression, thereby indicating that ST6Gal-I may mediate the invasiveness and tumorigenicity of NSCLC cells via the Notch1/Hes1/MMPs pathway both in vitro and in vivo. Thus, our results provide a novel therapeutic approach for blocking metastasis in lung cancer patients.

Four Ln(III) complexes based on a new nitronyl nitroxide radical have been synthesized and structurally characterized: {Ln(hfac)3[NITPh(OMe)2]2} (Ln = Eu(1), Gd(2), Tb(3), Dy(4); NITPh(OMe)2 = 2-(3΄,4΄-dimethoxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide; hfac = hexafluoroacetylacetonate;). The single-crystal X-ray diffraction analysis shows that these complexes have similar mononuclear tri-spin structures, in which central Ln(III) ion is eight-coordinated by two oxygen atoms from two nitroxide groups and six oxygen atoms from three hfac anions. The variable-temperature magnetic susceptibility study reveals that there exist ferromagnetic interactions between Gd(III) and the radicals, and antiferromagnetic interactions between two radicals (JGd-Rad = 3.40 cm−1, JRad-Rad = -9.99 cm−1) in complex 2. Meanwhile antiferromagnetic interactions are estimated between Eu(III) (or Dy(III)) and radicals in complexes 1 and 4, and ferromagnetic interaction between Tb(III) and radicals in complex 3, respectively. This article is protected by copyright. All rights reserved.

Five rare earth heterospin complexes [Ln(hfac)3(NITptBuPh)2], [LnIII = Eu (1), Tb (2), Dy (3), Ho (4), Er (5)] (hfac = hexafluoroacetylacetonate), were synthesized with the radical ligand NITptBuPh [2-(4′-tert-butylphenyl)-4, 4,5, 5-tetramethylimidazoline-1-oxyl-3-oxide]. These complexes exhibit similar structures. All of them crystallize in the monoclinic space group P21/c, and consist of discrete mononuclear molecules. The central LnIII ion is eight-coordinate with a distorted dodecahedral environment. The NITptBuPh radical acts as monodentate ligand towards LnIII ion through the NO group. The magnetic studies suggested weak antiferromagnetic interactions between LnIII ion and radicals in 1, 3, 4, and 5, but weak ferromagnetic interaction in 2.

Light-weight aluminum (Al) alloys have widespread applications. However, most Al alloys have inherently low mechanical strength. Nanotwins can induce high strength and ductility in metallic materials. Yet, introducing high-density growth twins into Al remains difficult due to its ultrahigh stacking-fault energy. In this study, it is shown that incorporating merely several atomic percent of Fe solutes into Al enables the formation of nanotwinned (nt) columnar grains with high-density 9R phase in Al(Fe) solid solutions. The nt Al-Fe alloy coatings reach a maximum hardness of ≈5.5 GPa, one of the strongest binary Al alloys ever created. In situ uniaxial compressions show that the nt Al-Fe alloys populated with 9R phase have flow stress exceeding 1.5 GPa, comparable to high-strength steels. Molecular dynamics simulations reveal that high strength and hardening ability of Al-Fe alloys arise mainly from the high-density 9R phase and nanoscale grain sizes.

Due to its high performance/cost ratio, a GPU cluster is an attractive platform for large scale general-purpose computation and visualization applications. However, the programming model for high performance general-purpose computation on GPU clusters remains a complex problem. In this paper, we introduce the Zippy frame-work, a general and scalable solution to this problem. It abstracts the GPU cluster programming with a two-level parallelism hierarchy and a non-uniform memory access (NUMA) model. Zippy preserves the advantages of both message passing and shared-memory models. It employs global arrays (GA) to simplify the communication, synchronization, and collaboration among multiple GPUs. Moreover, it exposes data locality to the programmer for optimal performance and scalability. We present three example applications developed with Zippy: sort-last volume rendering, Marching Cubes isosurface extraction and rendering, and lattice Boltzmann flow simulation with online visualization. They demonstrate that Zippy can ease the development and integration of parallel visualization, graphics, and computation modules on a GPU cluster.

Most metallic glasses are brittle as deformation induces low-density sporadic shear bands and severe shear localization proceeding catastrophic failure. Here, it is demonstrated that the introduction of crystalline nanolayers with appropriate dimension can substantially suppress shear localization in metallic glasses, as manifested by ubiquitous ductile dimples in amorphous phase. Furthermore, dimple sizes can be tailored by tuning the dimension of layer thickness. Additionally unlike instantaneous crack propagation occurring in most metallic glasses, crack propagation occurs in a highly periodic and “zigzag” fashion, and shows clear size dependence for metallic glass nanolaminates. Thus, it is a promising approach to promote ductility in metallic glasses while maintaining high strength by synthesizing metallic glass nanolaminates with certain layer thickness. Molecular dynamics simulations demonstrate that crystalline/amorphous interfaces can block crack propagation in crystalline layers and delocalize strain in amorphous layers, and suggest that “zigzag” crack propagation could be achieved through dislocation slips in crystalline layers.

Two experiments were carried out to investigate the effects of feeding diets containing faba beans and peas on the concentration, flow and composition of total, protein-bound and free amino acids (AA) in pancreatic juice collected from young pigs fitted with a pancreatic pouch re-entrant cannula. In Experiment 1, eight barrows, with an average initial weight of 8.5 kg, were fed one of two semi-purified diets formulated to contain 200 g kg -1 crude protein (CP) according to a completely randomised design. In one of the diets, soya bean meal was the sole protein source ; in the other diet, soya bean meal and faba beans (cv Fibro ; dark-flowering) each supplied 50% of the dietary CP. In Experiment 2, five barrows, with an average initial weight of 18.1 kg, were fed one of two diets formulated to contain 150 g kg -1 CP with peas (cv Ascona or cv Radley) as the sole protein source. There was no effect (P > 0.05) of the diet, 8 h sampling period or experimental period on the concentration (mM), composition (% and g 16 g N -1 ) and flow (mmol 24 h -1 ) of total, protein-bound and free AA or on the percentage of protein-bound AA in pancreatic juice. The concentrations of total, protein-bound and free AA were higher in pancreatic juice collected from younger pigs in Experiment 1 than in pancreatic juice collected from older pigs in Experiment 2. However, the daily flows of total, protein-bound and free AA in pancreatic juice were similar in both experiments. The percentages of protein-bound AA in pancreatic juice were similar in both experiments. In conclusion, the concentrations, compositions and flows of total, protein-bound and free AA in pancreatic juice were not affected by diet, 8 h sampling period or experimental period.