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961.
962.
A new silver nanochain SERS analytical platform to detect trace hexametaphosphate with a rhodamine S molecular probe
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Guangyun Shang Chongning Li Guiqing Wen Xinghui Zhang Aihui Liang Zhiliang Jiang 《Luminescence》2016,31(3):640-648
Using AgNO3 as the precursor, stable silver nanochain (AgNC) sols, orange‐red in color, were prepared using hydrazine hydrate. A strong surface plasmon resonance Rayleigh scattering (RRS) peak occurred at 420 nm plus two surface plasmon resonance (SPR) absorption peaks at 410 nm and 510 nm. Rhodamine S (RhS) cationic dye was absorbed on the as‐prepared AgNC substrate to obtain a RhS–AgNC surface‐enhanced Raman scattering (SERS) nanoprobe that exhibited a strong SERS peak at 1506 cm–1 and a strong RRS peak at 375 nm. Upon addition of the analyte sodium hexametaphosphate (HP), it reacted with RhS, which resulted in a decrease in the SERS and RRS peaks that was studied in detail. The decreased SERS and RRS intensities correlated linearly with HP concentration in the range of 0.0125–0.3 µmol/L and 0.05–1.0 µmol/L, with a detection limit of 6 nmol/L and 20 nmol/L HP respectively. Due to advantages of high sensitivity, good selectivity and simple operation, the RhS molecular probes were used to determine HP concentration in real samples. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
963.
Ni3FeN Nanoparticles Derived from Ultrathin NiFe‐Layered Double Hydroxide Nanosheets: An Efficient Overall Water Splitting Electrocatalyst
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964.
965.
Zhenkui Qin Yun Li Baofeng Su Qi Cheng Zhi Ye Dayan A. Perera Michael Fobes Mei Shang Rex A. Dunham 《Marine biotechnology (New York, N.Y.)》2016,18(2):255-263
Channel catfish (Ictalurus punctatus) is the most important freshwater aquaculture species in the USA. Genetically enhanced fish that are sterile could both profit the catfish industry and reduce potential environmental and ecological risks. As the first step to generate sterile channel catfish, three sets of zinc finger nuclease (ZFN) plasmids targeting the luteinizing hormone (LH) gene were designed and electroporated into one-cell embryos, different concentrations were introduced, and the Cel-I assay was conducted to detect mutations. Channel catfish carrying the mutated LH gene were sterile, as confirmed by DNA sequencing and mating experiments. The overall mutation rate was 19.7 % for 66 channel catfish, and the best treatment was ZFN set 1 at the concentration 25 μg/ml. To our knowledge, this is the first instance of gene editing of fish via plasmid introduction instead of mRNA microinjection. The introduction of the ZFN plasmids may have reduced mosaicism, as mutated individuals were gene edited in every tissue evaluated. Apparently, the plasmids were eventually degraded without integration, as they were not detectable in mutated individuals using PCR. Carp pituitary extract failed to induce spawning and restoration of fertility, indicating the need for developing other hormone therapies to achieve reversal of sterility upon demand. This is the first sterilization achieved using ZFN technology in an aquaculture species and the first successful gene editing of channel catfish. Our results will help understand the roles of the LH gene, purposeful sterilization of teleost fishes, and is a step towards control of domestic, hybrid, exotic, invasive, and transgenic fishes. 相似文献
966.
Duodenal‐jejunal bypass surgery induces hepatic lipidomic alterations associated with ameliorated hepatic steatosis in mice
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967.
Yilun Shang 《PloS one》2015,10(3)
Large-scale time-evolving networks have been generated by many natural and technological applications, posing challenges for computation and modeling. Thus, it is of theoretical and practical significance to probe mathematical tools tailored for evolving networks. In this paper, on top of the dynamic Estrada index, we study the dynamic Laplacian Estrada index and the dynamic normalized Laplacian Estrada index of evolving graphs. Using linear algebra techniques, we established general upper and lower bounds for these graph-spectrum-based invariants through a couple of intuitive graph-theoretic measures, including the number of vertices or edges. Synthetic random evolving small-world networks are employed to show the relevance of the proposed dynamic Estrada indices. It is found that neither the static snapshot graphs nor the aggregated graph can approximate the evolving graph itself, indicating the fundamental difference between the static and dynamic Estrada indices. 相似文献
968.
969.
Jian-Li Shang Hui Guo Zai-Shun Li Biao Ren Zheng-Ming Li Huan-qin Dai Li-Xin Zhang Jian-Guo Wang 《Bioorganic & medicinal chemistry letters》2013,23(3):724-727
A total of 29 novel sulfenamide compounds were synthesized, spectroscopically characterized and evaluated in vitro for antimicrobial activity against various infectious pathogens. Compounds 1b and 2c exhibited potent inhibition against clinical Methicillin-resistant Staphylococcus aureus (MRSA) strains with minimum inhibitory concentration (MIC) values of 1.56 μg/mL. 相似文献
970.
Xiaoying Liu Li Tian Yu Shang Jiusheng Jiang Jilin Zhang Jiayi Wei Dongxin Liu Wengang Fang Xinyue Zhao Hao Yu Yuhua Chen Deshu Shang 《Neurochemical research》2019,44(4):905-916
Neurochemical Research - Neuroinflammation is an important part of the development of neurodegenerative diseases such as Alzheimer’s disease (AD), Parkinson’s and amyotrophic lateral... 相似文献