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31.
'Magic mushrooms' (MMs) are psychoactive fungi containing the hallucinogenic compounds, psilocin (1) and psilocybin (2). Since June 6, 2002, these fungi have been regulated by the Narcotics and Psychotropics Control Law in Japan. Because there are many kinds of MMs and they are sold even as dry powders in local markets, it is very difficult to identify the original species of the MMs by morphological observation. Therefore, we investigated the internal transcribed spacer (ITS) region in the ribosomal RNA gene of MMs obtained in Japanese markets to classify them by a genetic approach. Based on the size and nucleotide sequence of the ITS region amplified by PCR, tested MMs were classified into 6 groups. Furthermore, a comparison of the DNA sequences of the MMs with those of authentic samples or with those found in the databases (GenBank, EMBL and DDBJ) made it possible to identify the species of tested MMs. Analysis by LC revealed that psilocin (1) was contained at the highest level in Panaeolus cyanescens among the MMs, but was absent in the Amanita species.  相似文献   
32.
The electron-beam technology was applied to reduce the emission of polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) in a flue gas of 1000 m(3)N/h from the municipal solid waste incinerator (MSWI) at a temperature of 200 degrees C. More than 90% decomposition of PCDD/Fs was obtained using an electron accelerator at a dose of 14 kGy. The decomposition was initiated through reactions with OH radicals produced by the irradiation of flue gases, followed by oxidation such as the ring cleavage of the aromatic ring, the dissociation of ether bond, and dechlorination. The cost analysis estimated that the electron-beam system can cut the annualized cost by approximately 50% for the treatment of PCDD/Fs in a pre-dusted MSWI flue gas as compared with a bag-filter system when operating on electricity generated from an incineration. Electron-beam technology is an economically and technologically useful method for reducing PCDD/Fs in an incineration flue gas.  相似文献   
33.
Investigation of pesticide residues in foods distributed in Kitakyushu City   总被引:2,自引:0,他引:2  
We investigated 160 kinds of pesticide residues in 715 samples of 116 kinds of foods distributed in Kitakyushu city. Sixty kinds of pesticides were detected in 55 kinds of foods (204 samples) in the range of 0.002-22 mg/kg. Five kinds of pesticides in 7 samples violated the residue standards and the indication of "unused". The detection ratios of unregulated pesticide in domestic and imported foods were 27.8 and 33.0%, respectively. Iprodione, dicofol, diethofencarb, procymidone and chlorfenapyr (for domestic food) and total bromine, benomyl, chlorpyrifos, dicofol, fenvalerate, cypermethrin and dimethoate (for imported food) showed relatively high detection ratios. Chinese cabbage, garland chrysanthemum, tomatoes and green teas (domestic) and broccoli, bananas, grapefruit, lemons, oranges, frozen edamame and frozen kidney beans (imported) showed high relative pesticide detection ratios. Residual pesticides were detected with relatively high frequency in imported fruits, imported frozen foods and imported processed foods.  相似文献   
34.
Xyloglucan is a major hemicellulosic component in plant cell walls. Phytopathogenic fungi secrete cell wall-degrading enzymes on their infection to hosts, while the nature of the cell wall-lytic enzymes of such fungi are yet to be fully understood. Verticillium dahliae is a soil-borne fungus that causes vascular wilt diseases in a variety of commercially important crops worldwide. We purified two types of xyloglucanases, XEG12A and XEG74B, from the culture of naturally isolated Verticillium dahliae strain 2148. XEG12A showed a molecular size of 23 kDa with its maximal activity at pH 7.5. XEG12A specifically hydrolyzed xyloglucan with no activity on other β-glucans. XEG74B had a molecular size of 110 kDa with its optimum pH at 6.0. XEG74B primarily hydrolyzed xyloglucan, with a slight activity on β-1,3-1,4-glucan. Analysis of hydrolytic products of xyloglucanooligasaccharide (XXXGXXXG) by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) revealed that the both enzymes cleaved β-1,4-glucosidic linkage at the position of unbranched chain, while XEG74B showed a little fluctuation with the cleavage site. Both enzymes did not hydrolyzed xyloglucanoheptasaccharide (XXXG) at all. N-Terminal and internal amino acid sequencing of the enzymes revealed that XEG12A and XEG74B belonged to Glycoside Hydrolase (GH) Families 12 and 74, respectively. Based on these results we concluded that V. dahliae XEG12A and XEG74B were xyloglucan-specific endo-β-1,4-glucanases (EC 3.2.1.151).  相似文献   
35.
A large number of 3D models are created on computers and available for networks. Some content-based retrieval technologies are indispensable to find out particular data from such anonymous datasets. Though several shape retrieval technologies have been developed, little attention has been given to the points on human's sense and impression (as known as Kansei) in the conventional techniques, In this paper, the authors propose a novel method of shape retrieval based on shape impression of human's Kansei. The key to the method is the Gaussian curvature distribution from 3D models as features for shape retrieval. Then it classifies the 3D models by extracted feature and measures similarity among models in storage.  相似文献   
36.
A gliding arc is a plasma that can be operated at atmospheric pressure and applied for plasma surface treatment for adhesion improvement. In the present work, glass-fibre-reinforced polyester plates were treated using an atmospheric pressure gliding arc discharge with an air flow to improve adhesion with a vinylester adhesive. The treatment improved wettability and increased the polar component of the surface energy and the density of oxygen-containing polar functional groups at the surfaces. Double cantilever beam specimens were prepared for fracture mechanics characterisation (fracture resistance as a function of nominal mode mixity) of the laminate adhesive interface. It was found that gliding arc treatment significantly increases the interfacial fracture energy and fracture resistance in comparison with a standard peel ply treatment, although the mixed mode fracture energy of the gliding arc treated specimen was not as high as that of the laminate itself.  相似文献   
37.
The catalytic dehydro-aromatization reaction over Mo/HZSM-5 catalyst was drastically stabilized by the co-addition of 5.4% H2 and 1.8% H2O to methane feed at 750 °C, 0.3 MPa and methane space velocity of 3000 mL g−1 h−1, suppressing the coke formation effectively, compared with single hydrogen or steam addition.  相似文献   
38.
39.
Disruption of the skin barrier function caused by epidermal hyper-proliferation, results in the skin becoming dry and showing high transepidermal water loss (TEWL). Gamma linolenic acid (GLA) is reportedly efficacious for treating TEWL and epidermal hyper-proliferation. In this study, to elucidate the effect of GLA-rich oil on skin function, GLA-containing food was given to adults with dry skin or mild atopic dermatitis and skin parameters were evaluated. In the results, we recognized beneficial effects on the TEWL index. The efficacy of GLA was also demonstrated to be statistically significant especially in subjects with pro-inflammatory features. The results suggest that the mechanism of improvement of skin barrier has been associated with possible generation of anti-inflammatory metabolites from GLA. The clinical physician also confirmed that none of the subjects showed any noteworthy side effects. GLA-enriched food appears to be safe and to improve skin barrier function in subjects with dry skin conditions and mild atopic dermatitis.  相似文献   
40.
Polyynes were prepared from pellets of a perylene derivative, 3,4,9,10-perylene tetracarboxylic dianhydride (PTCDA), and graphite by liquid-phase laser ablation, using solvents of methanol, ethanol, 1-propanol, 1-butanol, t-butyl alcohol, n-hexane, and decalin. The amounts of polyynes produced from PTCDA strongly depended on the polarity of the solvent, while those from graphite did not. Polar functional groups of acid-anhydride side chains in PTCDA are believed to influence the amounts of C2 radicals produced by laser ablation. The long-chain polyyne C28H2 was detected in a chromatogram of a solution obtained from a graphite pellet and solvent decalin.  相似文献   
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