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101.
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Biodegradation by activated sludge and toxicity of tetracycline into a semi-industrial membrane bioreactor 总被引:1,自引:0,他引:1
Much attention has been devoted recently to the fate of pharmaceutically active compounds such as tetracycline antibiotics in soil and water. Tetracycline (TC) biodegradability by activated sludge derived from membrane bioreactor (MBR) treating swine wastewater via CO2-evolution was evaluated by means of modified Sturm test, which was also used to evaluate its toxicity on carbon degradation. The impact of tetracycline on a semi-industrial MBR process was also examined and confronted to lab-scale experiments. After tetracycline injection in the pilot, no disturbance was detected on the elimination of organic matters and ammonium (nitrification), reaching after injection 88% and 99% respectively; only denitrification was slightly affected. Confirming the ruggedness and the superiority of membrane bioreactors over conventional bioreactors, no toxicity was observed at the considered level of TC in the pilot (20 mg TOC L−1), while at lab-scale sodium benzoate biodegradation was completely inhibited from 10 mg TOC L−1 TC. The origin of the activated sludge showed a significant impact on the performances, since the ultimate biodegradation was in the range −50% to −53% for TC concentrations in the range 10–20 mg TOC L−1 with conventional bioreactor sludge and increased to 18% for 40 mg TOC L−1 of TC with activated sludge derived from the MBR pilot. This confirmed the higher resistance of activated sludge arising from membrane bioreactor. 相似文献
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Solar Absorber Gel: Localized Macro‐Nano Heat Channeling for Efficient Plasmonic Au Nanoflowers Photothermic Vaporization and Triboelectric Generation
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Minmin Gao Connor Kangnuo Peh Huy Thong Phan Liangliang Zhu Ghim Wei Ho 《Liver Transplantation》2018,8(25)
Plasmonic nanoparticles with outstanding photothermal conversion efficiency are promising for solar vaporization. However, the high cost and the required intense light excitation of noble metals, hinder their practical application. Herein, an inexpensive 3D plasmonic solar absorber gel that embraces all the desirable optical, thermal, and wetting properties for efficient solar vaporization is reported. The broadband absorption and strong near‐field intertip enhancement of the sparsely dispersed gold nanoflowers contribute to efficient light‐to‐heat conversion, while the macro‐nano thermal insulative silica gel retains and channels the plasmonic heat directly to the water pathways contained within the porous gel. The plasmonic‐based solar absorber gel shows a vaporization efficiency of 85% under solar irradiation of 1 sun intensity (1 kW m?2). Moreover, the porous gel framework exhibits high mechanical stability and antifouling properties, potentially useful for polluted/turbid water evaporation. Complementary water condensation‐induced triboelectricity can be harvested alongside fresh water condensate, granting simultaneous fresh water production and electricity generation functionalities. The facile sol‐gel synthesis at room temperature makes the solar absorber gel highly adaptable for practical large‐scale photothermal applications. 相似文献
106.
Solar Absorber Gel: Solar Absorber Gel: Localized Macro‐Nano Heat Channeling for Efficient Plasmonic Au Nanoflowers Photothermic Vaporization and Triboelectric Generation (Adv. Energy Mater. 25/2018)
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107.
Huong T.T. Phan Naofumi Shimokawa Neha Sharma Masahiro Takagi Mun'delanji C. Vestergaard 《Biochemistry and Biophysics Reports》2018
Oxidized cholesterol has been widely reported to contribute to the pathogenesis of Alzheimer's disease (AD). However, the mechanism by which they affect the disease is not fully understood. Herein, we aimed to investigate the effect of 7-ketocholesterol (7keto) on membrane-mediated aggregation of amyloid beta (Aβ-42), one of the critical pathogenic events in AD. We have shown that when cholesterol is present in lipid vesicles, kinetics of Aβ nuclei formation is moderately hindered while that of fibril growth was considerably accelerated. The partial substitution of cholesterol with 7keto slightly enhanced the formation of Aβ-42 nuclei and remarkably decreased fibril elongation, thus maintaining the peptide in protofibrillar aggregates, which are reportedly the most toxic species. These findings add in understanding of how cholesterol and its oxidation can affect Aβ-induced cytotoxicity. 相似文献
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Antin ociceptive activity of nicotine 总被引:1,自引:0,他引:1
D V Phan M Dóda A Bite L Gy?rgy 《Acta physiologica Academiae Scientiarum Hungaricae》1973,44(1):85-93
110.
Brahim Heddi Nerea Martín-Pintado Zhalgas Serimbetov Teuku?Mahfuzh?Aufar Kari Anh Tuan Phan 《Nucleic acids research》2016,44(2):910-916
G-quadruplexes are non-canonical structures of nucleic acids, in which guanine bases form planar G-tetrads (G·G·G·G) that stack on each other in the core of the structure. G-quadruplexes generally contain multiple times of four (4n) guanines in the core. Here, we study the structure of G-quadruplexes with only (4n - 1) guanines in the core. The solution structure of a DNA sequence containing 11 guanines showed the formation of a parallel G-quadruplex involving two G-tetrads and one G-triad with a vacant site. Molecular dynamics simulation established the formation of a stable G-triad·water complex, where water molecules mimic the position of the missing guanine in the vacant site. The concept of forming G-quadruplexes with missing guanines in the core broadens the current definition of G-quadruplex-forming sequences. The potential ability of such structures to bind different metabolites, including guanine, guanosine and GTP, in the vacant site, could have biological implications in regulatory functions. Formation of this unique binding pocket in the G-triad could be used as a specific target in drug design. 相似文献