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Comprehensive Summary: Binary polyantimony clusters, namely [Cu2Sb14]4– and [Ag2Sb14]4–, containing coinage metals, were successfully synthesized and characterized, in which two homoatomic Sb73– subunits are bridged by two coinage metals in η4:η1 and η1:η1 coordination modes, respectively. In [Cu2Sb14]4–, two bridging Cu ions and two Sb atoms form a planar rhombic unit, which was revealed to have antiaromatic properties by theoretical calculations. Further electron structure and bonding analysis confirmed the presence of delocalized bonds in the rhombic unit and the metallophilic interaction between two formal M+ ions. [ABSTRACT FROM AUTHOR]

In this paper, we report the synthesis and structural characterisation of two hetero-metallic clusters, [(CO)3CrSn5Cr(CO)3]4− and [(CO)3MoSn5Mo(CO)3]4−, both of which have a pentagonal bipyramidal core. The structures are similar to that of previously reported [(CO)3MoPb5Mo(CO)3]4− and our analysis of the bonding suggests that they are best formulated as containing Sn54− rings bridging two zerovalent M(CO)3 fragments. The electronic structure is compared to two isolobal M2E5 clusters, [CpCrP5CrCp]− and Tl77−, both of which show clear evidence for trans-annular bonds between the apical atoms that is not immediately obvious in the title clusters. Our analysis shows that the balance between E-E and M-M bonding is a delicate one, and shifts in the relative energies of the orbitals on the E5 and M2 fragments generate a continuum of bonding situations linked by the degree of localisation of the cluster LUMO. [ABSTRACT FROM AUTHOR]

In this work, we synthesize naked tin cluster anion Sn368−, representing the first example of pure Sn nanowire assembled through oxidative coupling reactions of a super atomic cluster Sn94−. Theoretical analysis confirm the presence of aromaticity for each Sn9 unit showing four adjacent aromatic subunits bridged by parallel Sn–Sn bonds. [ABSTRACT FROM AUTHOR]

Abstract: A star-like amphiphilic copolymer was synthesized via RAFT polymerization by using a pentaerythritol-based compound (PTDBA) as a chain transfer agent with Styrene and DMAEMA as monomers. The polymer structure was characterized by FTIR, 1H NMR, 13C NMR and SEC/MALLS. After the retardation period, the molecular weight of PS-CTA and PMMA-CTA increased linearly with monomer conversion. The amphiphilic copolymer self-assembled into spherical micelles when water was added into its DMF solution. The particle size and polydispersity index (PDI) of the micelles in deionized water were about 406nm and 0.113, respectively. In a pH 10 buffer solution and low micelle concentration, the micelle size decreased with temperature increase. At higher temperatures and micelle concentrations the size increased, resulting in precipitation among agglomerating micelles. This phenomenon was not observed in deionized water. Furthermore, the copolymer effectively prolonged the release time of chlorambucil (CLB) in deionized water. [Copyright &y& Elsevier]

Abstract: Using hydrophobic acrylic acid-2-ethylhexyl ester (AAEHE) as a comonomer of methacrylic acid (MAA), a series of hydrophobically modified (HM) poly(methacrylic acid) (PMAA) (HMPMAA) hydrogels were prepared by UV solution copolymerization and studied as controlled-release matrices. The result indicates that swelling degree of the HMPMAA hydrogels can sensitively respond to change in pH. However, the presence of hydrophobic AAEHE segments influences swelling kinetics of PMAA hydrogel evidently. Using p-hydroxyanisole (PHAS) as a model molecule, controlled-release behaviors of the HMPMAA hydrogels were investigated. It is found that the presence of hydrophobic AAEHE segments can markedly slow down the release rate of PHAS from PMAA-based hydrogels regardless of pH 1.4 or 7.4. [Copyright &y& Elsevier]

Nonalcoholic fatty liver disease (NAFLD) has emerged as one of the most common chronic liver disease over the past decades. Endoplasmic reticulum stress (ERS) plays a pivotal role during the development of NAFLD. This study aims to analyze the potential role of protein disulfide isomerase A3 precursor (PDIA3), one of the ER chaperones, in free fatty acid-induced cell model of NAFLD. Human liver L02 cell line was treated with sodium palmitate for 24 hours, which developed severe intracellular lipid accumulation. The increased protein level of PDIA3 was detected via immunoblotting analysis in the fat loaded cell models of NAFLD. siRNA-mediated knockdown of PDIA3 in L02 cells not only increased the cellular lipid accumulation, but also exacerbated hepatocytes apoptosis induced by sodium palmitate. Further investigation revealed that knockdown of PDIA3 up-regulated protein expression of fatty acid synthase (FAS), a key enzyme involved in fatty acid synthesis. PDIA3 knockdown also up-regulated key molecules of ERS pathway, including glucose-regulated protein 78 (GRP78), phospho-PKR-like ER kinase (p-PERK), and C/EBP homologous protein (CHOP). Our results suggested that ER chaperone PDIA3 plays a pivotal role in FFA-induced hepatocyte steatosis and apoptosis. [ABSTRACT FROM AUTHOR]

Abstract: Superfine grinding technology is a new type of food processing that is employed to produce powders with outstanding properties such as high solubility, dispersion, adsorption, chemical reactivity and fluidity. The objective of this work was to study the superfine grinding technology on the silver carp bone and to optimize the operational parameters. The optimum processing conditions of superfine grinding were: feeding pressure of 0.85MPa, grinding pressure of 1.0MPa, feeding rate of 0.0325g/s, feeding particle size of 150–300μm and one pass through the grinder. Silver carp bone powder with average particle size (D 50) of 7.65μm was produced at these conditions. It was found that the smaller particle size of the powder, the higher its fluidity, solubility, solubility of protein, electric conductivity and water holding capacity of the powder were. So the quality of the products produced by the superfine grinding technology was said to be improved. [Copyright &y& Elsevier]

Abstract: A pH-responsive amphiphilic hydrogel with interpenetrating polymer networks (IPN) structure for controlled drug release was proposed. The IPN was constructed with hydrophilic poly(acrylic acid) (PAA) and hydrophobic poly(butyl acrylate) (PBA). Using drug N-acetyl-5-methoxytryptamine (melatonin, MEL) as a model molecule, the controlled drug release behaviors of the IPN were investigated. It is found that not only the release of MEL from the IPN can respond to change in pH, but also the presence of hydrophobic network can overcome disadvantageous burst effect of hydrophilic network. This may be a result of hydrophobic aggregation encapsulating MEL molecules. [Copyright &y& Elsevier]

Abstract: This paper studied the phenomenon of room creep deformation and its effect on tensile property of a X70 pipeline steel under stress-control loading pattern using round tensile test specimen. Significant time-dependent deformation under constant load was observed in the steel at room temperature, and the deformation is not only dependent on loading stress rate but also dependent on the loading process. It is also found that the loading-unloading-reloading process reduces the subsequent creep strain, while the occurrence of room temperature creep obviously enhances the subsequent yielding strength and the flow stresses. [Copyright &y& Elsevier]