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81.
Yamanaka H Moriyoshi K Ohmoto T Ohe T Sakai K 《Applied biochemistry and biotechnology》2007,136(1):39-51
Novel bisphenol A (BPA)-degrading bacterial strains, designated as BP-2CK, BP-21DK, and BP-22DK, were isolated from kimchi,
a traditionally fermented food. These isolates were identified as Bacillus pumilus and efficiently degraded BPA in a medium supplemented with nutrients such as peptone, beef extract, and yeast extract. Strains
BP-2CK, BP-21DK, and BP-22DK successfully degraded 25, 25, and 50 ppm of BPA, respectively, and all strains exhibited BPA-degrading
activity in the presence of 10% NaCl. Accumulation of the metabolites including 4-hydroxyacetophenone, one of the intermediates
produced by the other BPA-degrading bacteria, was not observed in BPA degradation by the isolated strains. These results indicate
that the isolated food-derived bacteria are applicable for the construction of efficient and safer systems for the removal
of BPA. 相似文献
82.
We propose succinct data structures for text retrieval systems supporting document listing queries and ranking queries based on the tf*idf (term frequency times inverse document frequency) scores of documents. Traditional data structures for these problems support queries only for some predetermined keywords. Recently Muthukrishnan proposed a data structure for document listing queries for arbitrary patterns at the cost of data structure size. For computing the tf*idf scores there has been no efficient data structures for arbitrary patterns.Our new data structures support these queries using small space. The space is only 2/ times the size of compressed documents plus 10n bits for a document collection of length n, for any 0<1. This is much smaller than the previous O(nlogn) bit data structures. Query time is O(m+qlogn) for listing and computing tf*idf scores for all q documents containing a given pattern of length m. Our data structures are flexible in a sense that they support queries for arbitrary patterns. 相似文献
83.
84.
Okano K Taguchi M Fujiki M Yamashita T 《Angewandte Chemie (International ed. in English)》2011,50(52):12474-12477
Sucked into the vortex: Hydrogels with embedded Rhodamine?B dye showed stir-induced circularly polarized luminescence (CPL; see picture), the sense of which can be controlled by switching the stir direction from clockwise (CW) to counterclockwise (CCW) with slow cooling from the sol to gel states. The chiral alignment of the dye was erased by heating the sample above the gel-sol transition temperature. 相似文献
85.
Okano K Ogino S Kawamoto M Yamashita T 《Chemical communications (Cambridge, England)》2011,47(43):11891-11893
We demonstrated the formation of a photoinduced surface relief grating using thin films comprising a photochromic molecular motor, 9-(2-phenyl-2,3-dihydro-cyclopenta[a]naphthalen-1-ylidene)-9H-fluorene. Results show that mass migration occurred by patterned light irradiation prepared from interfered laser beams and a photomask. 相似文献
86.
Nitrite (NO(2)(-)) was photocatalytically reduced to dinitrogen (N(2)) in an aqueous suspension of two kinds of titanium(iv) oxide particles loaded with palladium and silver (Pd-TiO(2) and Ag-TiO(2)) at pH 8 under irradiation of UV light in the presence of sodium oxalate as a hole scavenger. The two metal-loaded TiO(2) photocatalysts had different roles in conversion of NO(2)(-) to N(2) and worked in an effective ensemble without conflict: (1) Pd-TiO(2) induced photocatalytic disproportionation of NO(2)(-) to N(2) and nitrate (NO(3)(-)) and (2) Ag-TiO(2) selectively reduced the thus-formed NO(3)(-) back to NO(2)(-) (partially to N(2)) with oxalate acting as a hole scavenger. When Pd-TiO(2) was used alone for NO(3)(-) reduction in the presence of sodium oxalate, Pd-TiO(2) induced fruitless photocatalytic decomposition of oxalate to carbon dioxide and dihydrogen. The presence of Ag-TiO(2) suppressed the fruitless decomposition of oxalate by Pd-TiO(2) because Ag-TiO(2) continuously provided NO(2)(-) in the reaction system using oxalate as a hole scavenger and Pd-TiO(2) therefore only worked as a photocatalyst for disproportionation of NO(2)(-) to N(2) and NO(3)(-) as it did when used alone. 相似文献
87.
R Iino K Hayama H Amezawa S Sakakihara SH Kim Y Matsumono K Nishino A Yamaguchi H Noji 《Lab on a chip》2012,12(20):3923-3929
Active efflux of drugs, such as antibiotics, from a cell is one of the major mechanisms that cause multi-drug resistance in bacteria. Here we report a method to assess drug efflux activity in individual Escherichia coli cells enclosed and isolated in a directly accessible femtoliter droplet array with a fluorogenic compound. The inhibitory effect of a chemical compound on an exogenously expressed efflux pump system from pathogenic bacteria was easily detected at the single-cell level. We also present a proof-of-principle experiment to screen for the gene encoding a drug efflux pump by collecting individual droplets containing single cells in which the drug efflux activity was restored after introduction of the exogenous gene from pathogenic bacteria. Our approach will be a useful tool to screen novel pump inhibitors and efflux pump genes, and to overcome infectious diseases caused by multi-drug-resistant bacteria. 相似文献
88.
Kunihiko Takabe Yasuhiro Iida Hidetaka Hiyoshi Masatoshi Ono Yoshihiko Hirose Yoshitaka Fukui Hidemi Yoda Nobuyuki Mase 《Tetrahedron: Asymmetry》2000,11(24):4825-4829
Enantioselective acetylation of 2-carbamoylmethyl-1,3-propanediol derivatives was catalyzed effectively by lipase PS to give monoacetates with high enantioselectivity: The enantioselectivity depended on the 2-carbamoylmethyl groups. The reaction of N-monoalkylcarbamoylmethyl-1,3-propanediol afforded the monoacetate with the (S)-configuration, whereas N,N-dialkylcarbamoylmethyl-1,3-propanediol gave the monoacetate with the (R)-configuration. 相似文献
89.
Junbo Deng Lu Pu Haibao Mu Guanjun Zhang Shigeyasu Matsuoka Akiko Kumada Kunihiko Hidaka 《Journal of Electrostatics》2013,71(4):739-745
The charge density distribution of the surface leader has never been measured before. Because the surface leader usually covers a long distance, and the surface potential caused by leader discharge is usually very high, this creates difficulties in measuring the potential distribution of the surface leader. In this paper, with a feedback type electrostatic probe based on a field-nullify technique, a charge density distribution scanning system is developed. A two-layer structure pipe is designed to lower the surface potential after discharge. In this way, the surface potential distribution caused by the residual charge of the leader discharge under the application voltage as high as to 40 kV can be measured. The surface charge density distribution including the leader and streamer is perfectly measured, which is in good agreement with the photograph. 相似文献
90.
The study of left-invariant Einstein metrics on compact Lie groups which are naturally reductive was initiated by D??Atri and Ziller (Mem Am Math Soc 18, (215) 1979). In 1996 the second author obtained non-naturally reductive Einstein metrics on the Lie group SU(n) for n ??? 6, by using a method of Riemannian submersions. In the present work we prove existence of non-naturally reductive Einstein metrics on the compact simple Lie groups SO(n) (n ??? 11), Sp(n) (n ??? 3), E 6, E 7, and E 8. 相似文献