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Xanthate has become the main organic pollutant in mine wastewater because of its widespread use as a flotation collector. Multilayer graphene oxide (MGO) exhibits excellent adsorption performance in removing organic contaminants from aqueous solutions that is attributed to its rich oxygen-containing functional groups and large specific surface area. MGO was prepared using the modified Hummers method. Moreover, MGO was characterised by Raman spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy (XPS). The adsorption of xanthate by MGO follows the Langmuir model, and thermodynamic studies have shown that the adsorption process can be completed spontaneously. The results of XPS analysis indicated that the oxygen content on the MGO surface decreased after the adsorption of xanthate, and the proportion of oxygen-containing functional groups was also significantly lower than that before adsorption. Molecular dynamics studies revealed that the head group of xanthates was closer to the surface of the MGO than the tail group. This research indicates that MGO can be successfully used to adsorb xanthate. In addition, the dispersion force between the head group of xanthates and the oxygen-containing functional group on the MGO surface was the dominant factor affecting the adsorption process. Multilayer graphene oxide can be used to remove xanthate in aqueous solutions, and the oxygen-containing groups on multilayer graphene oxide can provide adsorption sites for xanthate.

Foxtail millet (Setaria italica) is a monotypic species widely planted in China. However, residual atrazine, a commonly used maize herbicide, in soil, is a major abiotic stress to millet. Here, we investigated atrazine tolerance in millet based on the field experiments, then obtained an atrazine-resistant variety (Gongai2, GA2) and an atrazine-sensitive variety (Longgu31, LG31). To examine the effects of atrazine on genes and metabolites in millet plants, we compared the transcriptomic and metabolomic profiles between GA2 and LG31 seedling leaves. The results showed that 2,208 differentially expressed genes (DEGs; 501 upregulated, 1,707 downregulated) and 192 differentially expressed metabolites (DEMs; 82 upregulated, 110 downregulate) were identified in atrazine-treated GA2, while in atrazine-treated LG31, 1,773 DEGs (761 upregulated, 1,012 downregulated) and 215 DEMs (95 upregulated, 120 downregulated) were identified. The bioinformatics analysis of DEGs and DEMs showed that many biosynthetic metabolism pathways were significantly enriched in GA2 and LG31, such as glutathione metabolism (oxiglutatione, γ-glutamylcysteine; GSTU6, GSTU1, GSTF1), amino acid biosynthesis (L-cysteine, N-acetyl-L-glutamic acid; ArgB, GS, hisC, POX1), and phenylpropanoid biosynthesis [trans-5-o-(4-coumaroyl)shikimate; HST, C3′H]. Meanwhile, the co-expression analysis indicated that GA2 plants had enhanced atrazine tolerance owing to improved glutathione metabolism and proline biosynthesis, and the enrichment of scopoletin may help LG31 plants resist atrazine stress. Herein, we screened an atrazine-resistant millet variety and generated valuable information that may deepen our understanding of the complex molecular mechanism underlying the response to atrazine stress in millet.

Jing Qu,1 Weiwei Wang,1 Yanfei Feng,1 Longxing Niu,1 Mingzhong Li,1 Jicheng Yang,2 Yufeng Xie3 1National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, Suzhou 215123, People′s Republic of China; 2Cell and Molecular Biology Institute, College of Medicine, Soochow University, Suzhou 215123, People′s Republic of China; 3Department of Oncology, First Affiliated Hospital of Soochow University, Suzhou 215006, People′s Republic of ChinaCorrespondence: Mingzhong LiNational Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, No. 199 Ren’ai Road, Suzhou 215123, People’s Republic of ChinaTel +86-512-6706-1150Fax +86-512-6724-6786Email mzli@suda.edu.cnYufeng XieDepartment of Oncology, First Affiliated Hospital of Soochow University, No.188 Shizi Road, Suzhou 215006, People′s Republic of ChinaTel +86-512-6778-0645Email sdxyf@163.comIntroduction: Cancer gene therapy requires both effective tumor suppressor genes and safe vectors that express target genes efficiently. Inhibitor of growth 4 (ING4) inhibits tumor growth via multiple pathways. Interleukin-24 (IL-24) also has tumor-suppressive activity against a broad spectrum of human cancers. Adenovirus (Ad) vectors exhibit high infection efficiency, but potential toxicity related to high doses of adenovirus has led to careful reconsideration of their use in human clinical trials. Antheraea pernyi silk fibroin (ASF) is a cytocompatible and biodegradable natural polymer, and it possesses Arg–Gly–Asp sequences exhibiting a high binding affinity and selectivity for αvβ3 and αvβ5 integrin receptors, which are overexpressed in tumor vessels and most tumor cells.Methods: In this study, an Arg-Gly-Asp peptide-modified Ad vector coexpressing ING4 and IL-24 was constructed by homologous recombination of the dual gene coexpression transfer plasmid and RGD-modified pAdEasy-1 adenoviral backbone plasmid. The cationic ASF (CASF) was prepared by modifying ASF with low-molecular-weight PEI. The negatively charged Ad vector was modified with CASF to form a CASF/Ad complex.Results: Human hepatoma carcinoma SMMC-7721 cells and normal hepatic L-02 cells were infected with the CASF/Ad complex, which showed significantly higher infection efficiency than the naked Ad. The CASF/Ad complex could effectively mediate the expression of the target gene ING4 in SMMC-7721 cells and the secretion of the target gene IL-24 from SMMC-7721 cells, thus inducing apoptosis of hepatoma carcinoma SMMC-7721 cells. The viability of SMMC-7721 and L-02 cells infected with the CASF/Ad complex was further assessed, and it was found that the growth of SMMC-7721 cells was significantly inhibited but that the growth and proliferation of L-02 cells were not affected.Conclusion: The CASF/Ad complex constructed in this study, showing improved infection efficiency and enhanced suppressive effects on human hepatoma carcinoma SMMC-7721 cells, has the potential to reduce the dose of adenovirus and still maintain high infection efficiency and tumor inhibition.Keywords: silk fibroin, adenovirus, cationic modification, hepatoma carcinoma

The effects of a low-power electromagnetic pulse on the grain size and cooling curve of high-strength aluminum alloy 7A04 were investigated for various pulse duty cycles. This electromagnetic pulse treatment was found to effectively produce fine grains with globular crystals and a uniform microstructure for pulse duty cycles between 20 and 40%. The key factors that affected grain refinement under the electromagnetic pulse included the electromagnetic energy and the conversion frequency between $$ \varvec{B} $$ and $$ \varvec{E} $$ . The nucleation rate increased as the nucleation period was extended. A new kinetic condition of magnetic nucleation was explored by decreasing the critical Gibbs free energy in the electromagnetic pulse, which was more sensitive under low undercooling. In addition, the crystal orientation was controlled in such a solidification environment.