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91.
92.
93.
Solvated electrons in alkali metal-ammonia solutions have attracted attention as a prototype electronic conductor and chemical reducing agent for over a century. However, solvated electrons have not been realized in a high-temperature melt or glass of an oxide system to date. We demonstrated the formation of persistent solvated electrons in both a high-temperature melt and its glass by using the thermally stable electride [Ca(24)Al(28)O(64)](4+)·4e(-) (C12A7:e(-)) and controlling the partial pressure of oxygen. The electrical and structural properties of the resulting melt and glass differ from those of the conventional C12A7:O(2-) oxide, exhibiting metallic and hopping conduction, respectively, and a glass transition temperature that is ~160 kelvin lower than that of C12A7:O(2-) glass. Solvated electrons reside in cage structures in C12A7:e(-) and form a diamagnetic paired state.  相似文献   
94.
95.
Indonesian soy sauce is made using only soybeans as the nitrogenous source. Moromi obtained from fermentation of yellow soybeans using Aspergillus sojae as the starter was investigated. The fraction with molecular weights of less than 500 Da obtained by stepwise ultrafiltration was then fractionated by several chromatographic procedures, including gel filtration chromatography and RP-HPLC. Several chemical analyses, CE profiles, and taste profiles were performed to obtain the most intense umami fraction. The main components eliciting or enhancing the umami taste present in the fraction were purified and identified by protein sequencing, ESI-MS, and (1)H NMR at 400 MHz. Besides free l-glutamic acid and aspartic acid, free aromatic amino acids such as l-phenylalanine and l-tyrosine may also play an important role in impressing savory or umami taste of Indonesian soy sauce at their subthreshold concentrations and in the presence of salt and free acidic amino acids. This is reported as a new phenomenon of the so-called bitter amino acids.  相似文献   
96.
The human cytochrome P450 CYP1A1 gene was introduced into rice plants (Oryza sativa cv. Nipponbare). One-month-old CYP1A1 plants grown in soil clearly showed a healthy growth and tolerance to 8.8 microM atrazine and 50 microM simazine, but nontransgenic plants were completely killed by the herbicides. Although transgenic and nontransgenic plants metabolized the two herbicides into the same sets of compounds, CYP1A1 plants metabolized atrazine and simazine more rapidly than did control plants. In small-scale experiments, residual amounts of atrazine and simazine in the culture medium of CYP1A1 plants were 43.4 and 12.3% of those in control medium; those of nontransgenic Nipponbare were 68.3 and 57.2%, respectively. When cultivated in soil with 2.95 microM atrazine and 3.15 microM simazine for 25 days, CYP1A1 plants eliminated 1.3 times more atrazine and 1.4 times more simazine from the soil than did control plants. Thus, CYP1A1 rice plants make it possible to remove atrazine and simazine more rapidly from the culture medium and soil than can nontransgenic Nipponbare.  相似文献   
97.
We introduced the human cytochrome P450 gene CYP2B6 into rice plants (Oryza sativa L. cv. Nipponbare), and the CYP2B6-expressing rice plants became more tolerant to various herbicides than nontransgenic Nipponbare rice plants. In particular, CYP2B6 rice plants grown in soil showed tolerance to the chloroacetanilide herbicides alachlor and metolachlor. We evaluated the degradation of metolachlor by CYP2B6 rice plants to confirm the metabolic activity of the introduced CYP2B6. Although both CYP2B6 and nontransgenic Nipponbare rice plants could decrease the amount of metolachlor in plant tissue and culture medium, CYP2B6 rice plants could remove much greater amounts. In a greenhouse, the ability of CYP2B6 rice plants to remove metolachlor was confirmed in large-scale experiments, in which these plants appeared able to decrease residual quantities of metolachlor in water and soil.  相似文献   
98.
The waterchestnut ecosystem of Lake Kasumigaura is at the climax stage of eutrophication. Organic debris in the ecosystem showed highly dynamic fluctuations throughout the year. This was chiefly attributed to high viable fractions of organic matter in the hypereutrophic water. The stability of steady-state equilibrium of organic debris was found to be maintained even in such a dynamic ecosystem, likely due to the precedence of heterotrophic processes over autotrophic processes. Using a mathematical model approximated by in situ data, the turnover time of organic solutes was analyzed to be between four and six months through these active heterotrophic processes.  相似文献   
99.
pp. 859–864
Behavior of nitrogen in the media was investigated when the aqueous phase produced by methane fermentation was supplied as liquid fertilizer.
When the aqueous phase was supplied to masa-soil,      included in masa-soil was nitrified to      . Additionally, in masa-soil,       absorption was observed. On the other hand, in the case of coconut fiber and rockwool,     has been hardly nitrified. From above results, it was determined that       toxic effect from the aqueous phase on tomato plants growth was inhibited by means of the progress of nitrification and       absorption by masa-soil.
  However, nitrification was restrained so that       was fixed in masa-soil. On the other hand, in the sampled field soil,       was not fixed, and was nitrified immediately. In the field soil, there was a great deal of generated      . In comparison with masa-soil.  相似文献   
100.
The effect of (-)-epigallocatechin 3-gallate (EGCG), a major polyphenol of green tea, on neutrophil migration has been studied using multiwell-type Boyden chambers in vitro and a fluorescein isothiocyanate-labeled ovalbumin (FITC-OVA)-induced rat allergic inflammation model in vivo. EGCG inhibited rat neutrophil chemotaxis toward cytokine-induced neutrophil chemoattractant-1 (CINC-1) in a concentration-dependent manner. In addition, CINC-1-induced neutrophil chemotaxis was suppressed by the pretreatment of rat neutrophils with EGCG at the concentration over 15 microg/mL. EGCG caused concentration-dependent suppression of the transient increase in CINC-1-induced intracellular free calcium level in both rat neutrophils and rat CXC chemokine receptor 2 (CXCR2)-transfected HEK 293 cells. EGCG inhibited CINC-1 production by IL-1beta-stimulated rat fibroblasts (NRK-49F cells) and lipopolysaccharide-stimulated rat macrophages at the concentration over 50 microg/mL, a comparatively high concentration. Oral administration of EGCG (1.0 mg or 1.5 mg/rat) at 1 h before the challenge with FITC-OVA suppressed neutrophil infiltration into the air pouch (inflammatory site) in the air-pouch type FITC-OVA-induced allergic inflammation in rats. Chemokine levels in the pouch fluids, however, were not influenced by EGCG administration. The results suggest that EGCG suppressed neutrophil infiltration by a direct action on neutrophils, but not by indirect actions, including the suppression of chemokine production at the inflammatory site.  相似文献   
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