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Qin M.,Central South University | Liang Q.,Central South University | Pan A.,Central South University | Liang S.,Central South University | And 5 more authors.
Journal of Power Sources

A facile hydrothermal route has been developed to fabricate the metastable VO2 (B) ultra-thin nanobelt arrays, which can be converted into V2O5 porous nanobelt arrays after calcinating VO 2 (B) in air at 400 °C for 1 h. The influence of hydrothermal time to the crystallinity and morphology of the VO2 phase has been studied. A possible mechanism for the formation of VO2 nanobelt arrays has been proposed in this paper. As a cathode material for lithium ion batteries, the V2O5 nanobelt arrays show excellent rate capability and cycling stability. An initial discharge capacity of 142 mA h g-1 can be delivered at a current density of 50 mA g-1 with almost no capacity fading after 100 cycles. Even at a current density of 1000 mA g-1, they still exhibit the capacity of 130 mA h g -1 and superior capacity retention capability. The excellent electrochemical properties are attributed to the ultra-thin thickness and the porous structures of the nanobelts. © 2014 Elsevier B.V. All rights reserved. Source

Liang S.,Central South University | Qin M.,Central South University | Tang Y.,Central South University | Tang Y.,Key Laboratory of the Ministry of Education | And 5 more authors.
Metals and Materials International

Nanosheet-structured vanadium pentoxide (V2O5) has been fabricated by a sol-gel method. As revealed by the TEM, the as-synthesized V2O5 crystallites are composed of layer-by-layer stacked nanosheets. As a cathode material for lithium batteries, it exhibits much better electrochemical performance than the starting commercial V2O5 powders. A high specific discharge capacity of 264 mA h g−1 can be obtained for the nanosheet-structured electrodes, which retains the capacity of 90% after 50 cycles. However, the commercial V2O5 only delivers a specific discharge capacity of 206 mA h g−1 with a capacity retention of 64% after 50 cycles. Moreover, the nanosheet-structured V2O5 electrodes show much-improved C-rate capability. The superior cycling performance demonstrates that the nanosheet-structured V2O5 is a promising cathode material in lithium-ion battery applications. © 2014, The Korean Institute of Metals and Materials and Springer Science+Business Media Dordrecht. Source

Guo Y.,Key Laboratory of the Ministry of Education | Liu S.,Shandong University | Wang P.,Shandong University | Zhao S.,Key Laboratory of the Ministry of Education | And 6 more authors.

Aims: To investigate whether Oct4, Sox2 and Nanog, three core regulatory factors maintaining pluripotency and self-renewal of embryonic stem cells (ESCs), are coexpressed in human gliomas, and whether their expression might be linked to carcinogenesis and the formation of cancer stem cells (CSCs). Methods and results: Forty cases of human glioma were examined. The expression of Oct4, Sox2 and Nanog was analysed by immunohistochemistry, reverse transcription polymerase chain reaction and western blot. We found a positive correlation between the expression levels of Oct4, Sox2 and Nanog and tumour malignancy. Immunohistochemistry showed that Oct4 and Nanog were expressed in both the nuclei and the cytoplasm of glioma cells, whereas Sox2 was expressed only in the nuclei. Double immunofluorescence staining revealed that a majority of Oct4-positive cells coexpressed Sox2 and Nanog. More than 50% of Oct4-positive cells coexpressed the putative CSC markers CD133 and Nestin. Moreover, some cells exhibited Oct4 and Nanog immunoexpression in the cytoplasm, but the frequency of positive cells did not correlate with tumour malignancy. Conclusions: The present findings suggest that ESC-associated pathways are activated in human gliomas and that these may be involved in glioma progression, a role that is distinct from that in ESCs. © 2011 Blackwell Publishing Limited. Source

Hutton R.,Fudan University | Hutton R.,Key Laboratory of the Ministry of Education | Zou Y.,Fudan University | Zou Y.,Key Laboratory of the Ministry of Education | And 4 more authors.
Journal of Physics B: Atomic, Molecular and Optical Physics

In this paper we give a short introduction to the use of atomic spectroscopy in plasma diagnostics. Both older works and exciting new branches of atomic physics, which have relevance to diagnostics, are discussed. In particular we focus on forbidden lines in Be-like ions, lines sensitive to magnetic fields and levels which have a lifetime dependence on the nuclear spin of the ion, i.e. f-dependent lifetimes. Finally we mention a few examples of where tokamaks, instead of needing atomic data, actually provide new data and lead to developments in atomic structure studies. © 2010 IOP Publishing Ltd. Source

Zhou X.,Key Laboratory of the Ministry of Education | Zhou X.,Ningxia University | Zhang Y.,Key Laboratory of the Ministry of Education | Zhang Y.,Ningxia University | And 8 more authors.

In this study, the anti-proliferative and anticancer activity of azithromycin (AZM) was examined. In the presence of AZM, cell growth was inhibited more effectively in Hela and SGC-7901 cancer cells, relative to transformed BHK-21 cells. The respective 50% inhibition of cell growth (IC50) values for Hela, SGC-7901 and BHK-21 were 15.66, 26.05 and 91.00 μg/mL at 72 h post incubation, indicative of a selective cytotoxicity against cancer cells. Cell apoptosis analysis using Hoechst nuclear staining and annexin V-FITC binding assay further demonstrated that AZM was capable of inducing apoptosis in both cancer cells and transformed cells. The apoptosis induced by AZM was partly through a caspase-dependent mechanism with an up-regulation of apoptotic protein cleavage PARP and caspase-3 products, as well as a down-regulation of anti-apoptotic proteins, Mcl-1, bcl-2 and bcl-X1. More importantly, a combination of AZM and a low dose of the common anti-cancer chemotherapeutic agent vincristine (VCR), produced a selectively synergistic effect on apoptosis of Hela and SGC-7901 cells, but not BHK-21 cells. In the presence of 12.50 μg/mL of VCR, the respective IC50 values of Hela, SGC-7901 and BHK-21 cells to AZM were reduced to 9.47 μg/mL, 8.43 μg/mL and 40.15 μg/mL at 72 h after the incubation, suggesting that the cytotoxicity of AZM had a selective anti-cancer effect on cancer over transformed cells in vitro. These results imply that AZM may be a potential anticancer agent for use in chemotherapy regimens, and it may minimize side effects via reduction of dosage and enhancing the effectiveness common chemotherapeutic drugs. © 2012 by the authors; licensee MDPI, Basel, Switzerland. Source

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