Preparation of Polyoxymethylene/Exfoliated Molybdenum Disulfide Nanocomposite through Solid-State Shear Milling.

In this paper, the solid-state shear milling (S3M) strategy featuring a very strong three-dimensional shear stress field was adopted to prepare the high-performance polyoxymethylene (POM)/molybdenum disulfide (MoS2) functional nanocomposite. The transmission electron microscope and Raman measurement results confirmed that the bulk MoS2 particle was successfully exfoliated into few-layer MoS2 nanoplatelets by the above simple S3M physical method. The polarized optical microscope (PLM) observation indicated the pan-milled nanoscale MoS2 particles presented a better dispersion performance in the POM matrix. The results of the tribological test indicated that the incorporation of MoS2 could substantially improve the wear resistance performance of POM. Moreover, the pan-milled exfoliated MoS2 nanosheets could further substantially decrease the friction coefficient of POM. Scanning electron microscope observations on the worn scar revealed the tribological mechanism of the POM/MoS2 nanocomposite prepared by solid-state shear milling. The tensile test results showed that the pan-milled POM/MoS2 nanocomposite has much higher elongation at break than the conventionally melt-compounded material. The solid-state shear milling strategy shows a promising prospect in the preparation of functional nanocomposite with excellent comprehensive performance at a large scale.

Mo2 C/Reduced Graphene Oxide Composites with Enhanced Electrocatalytic Activity and Biocompatibility for Microbial Fuel Cells.

A simple, cost-effective strategy was developed to effectively improve the electron transfer efficiency as well as the power output of microbial fuel cells (MFCs) by decorating the commercial carbon paper (CP) anode with an advanced Mo2 C/reduced graphene oxide (Mo2 C/RGO) composite. Benefiting from the synergistic effects of the superior electrocatalytic activity of Mo2 C, the high surface area, and prominent conductivity of RGO, the MFC equipped with this Mo2 C/RGO composite yielded a remarkable output power density of 1747±37.6 mW m-2 , which was considerably higher than that of CP-MFC (926.8±6.3 mW m-2 ). Importantly, the composite also facilitated the formation of 3D hybrid biofilm and could effectively improve the bacteria-electrode interaction. These features resulted in an enhanced coulombic efficiency up 13.2 %, nearly one order of magnitude higher than that of the CP (1.2 %).

The Facile Synthesis of Branch-Trunk Ag Hierarchical Nanostructures and Their Applications for High-Performance H2O2 Electrochemical Sensors.

A novel branch-trunk Ag hierarchical nanostructure was synthesized via a galvanic replacement reaction combined with microwave-assisted synthesis using Te nanowire as a sacrificial template. The Te nanowire was synthesized via a hydrothermal process. We further investigated the potential application of the obtained hierarchical nanostructures in electrochemical sensor analysis. The results showed that the as-prepared sensor exhibited a wide linear range with 0.05 µM to 1.925 mM (R = 0.998) and the detection limit was estimated to be 0.013 µM (S/N = 3). These results indicate the branch-truck Ag hierarchical nanostructures are an excellent candidate material for sensing applications.

[Notch1 Gene Silenced by RNAi Inhibits Oncogenicity of Myeloma Cell Line].

OBJECTIVE: To investigate the effect of Notch1 gene silencing by RNA interference on oncogenicity of multiple myeloma cells in NOD/SCID mice. METHODS: Targeting-silenced Notch1 gene was target-sotenced by transfection of Notch1-shRNA in multiple myeloma RPMI8226 cells of NOD/SCID mouse myeloma models, and the change of the volume and speed of oncogenicity in myeloma mouse models were evaluated after Notch1 gene silencing, and ELISA was used to detect the serum expression level of IL-6 and VEGF in the tumor-bearing mice. RESULTS: After Notch1 gene was silenced by Notch1-shRNA, the speed of tumor formation was significantly inhibited and the tumor volume was reduced in the tumor-bearing mice, as compared with the control group, and the difference was statistically significant (P<0.05). The serum level of IL-6 and VEGF in the tumor-bearing mice significantly decreased in comparison with the control group (P<0.05 ). CONCLUSION: The oncogenicity of myeloma cells in the models NOD/SCID mouse myeloma is significantly inhibited by Notch1 gene-silencing, and its mechanism may relate with the decreased secretory level of IL-6 and VEGF after Notch1 gene silencing. Notch1 gene silencing can be used as a new strategy to treat multiple myeloma.

[Targeting Notch1 Gene Inhibits the Proliferation of Multiple Myeloma Cells].

OBJECTIVE: To investigate the effects of Notch1 gene silencing on the proliferation and apoptosis of multiple myeloma cells, and to find the new targets for the treatment of multiple myeloma. METHODS: Notch1-shRNA targeted silencing Notch1 gene was transfected into multiple myeloma RPMI8226 cells, the CCK-8 and flow cytometry were used to detect the proliferation and apoptosis of myeloma cells after Notch1-shRNA transfection, the real-time fluorescence quantitative PCR was used to analyze expression level of Notch1 mRNA, and the Western blot were used to detect the expression level of Notch1 signaling pathway-related protein, such as Hes-1, Jagged-1, Jagged-2, BCL-2, PTEN, AKT and P-AKT. RESULTS: The mRNA and protein expression levels of Notch1-shRNA transfected cells were significantly inhibited in the experimental group assayed by real time fluorescence quantitative PCR and Western blot, the mRNA and protein expression level were down-regulated to 66% + 0.1%, 88% + 3.4% respectively, as compared with the control group(P<0.05). CCK-8 results confirmed that the cell proliferation rate was significantly decreased in the experimental group 48 hours after transfection. Flow cytometry results showed that the cell apoptosis rate was significantly higher in the experimental group than that in the control group. The expression levels of downstream protein Hes1, p-AKT and BCL-2 were decreased, the level of PTEN increased significantly after Notch1 gene silencing. CONCLUSION: Notch1 gene silencing by transfection of Notch1-shRNA can inhibit the proliferation of myeloma cells and induce their apoptosis, and its mechanism is related to the activation of PTEN gene and p-AKT signaling. Notch1 signal can be used as a potential target for multiple myeloma therapy.

Holey tungsten oxynitride nanowires: novel anodes efficiently integrate microbial chemical energy conversion and electrochemical energy storage.

Holey tungsten oxynitride nanowires with superior conductivity, good biocompatibility, and good stability achieve excellent performance as anodes for both asymmetric supercapacitors and microbial fuel cells. Moreover, an innovative system is devised based on these as-prepared tungsten oxynitride anodes, which can simultaneously realize both energy conversion from chemical to electric energy and its storage.

Solar-microbial hybrid device based on oxygen-deficient niobium pentoxide anodes for sustainable hydrogen production.

Hydrogen gas is emerging as an attractive fuel with high energy density for the direction of energy resources in the future. Designing integrated devices based on a photoelectrochemical (PEC) cell and a microbial fuel cell (MFC) represents a promising strategy to produce hydrogen fuel at a low price. In this work, we demonstrate a new solar-microbial (PEC-MFC) hybrid device based on the oxygen-deficient Nb2O5 nanoporous (Nb2O5-x NPs) anodes for sustainable hydrogen generation without external bias for the first time. Owing to the improved conductivity and porous structure, the as-prepared Nb2O5-x NPs film yields a remarkable photocurrent density of 0.9 mA cm-2 at 0.6 V (vs. SCE) in 1 M KOH aqueous solution under light irradiation, and can achieve a maximum power density of 1196 mW m-2 when used as an anode in a MFC device. More importantly, a solar-microbial hybrid system by combining a PEC cell with a MFC is designed, in which the Nb2O5-x NPs electrodes function as both anodes. The as-fabricated PEC-MFC hybrid device can simultaneously realize electricity and hydrogen using organic matter and solar light at zero external bias. This novel design and attempt might provide guidance for other materials to convert and store energy.