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181.
The mean concentrations and daily intake of four antifungal agents were estimated based on the results of an analysis of 7,005 samples of food obtained in official inspections by Japanese local governments in fiscal year 1998. The mean concentration of diphenyl was 0.0004% of the allowable limit, and those of imazalil, o-phenylphenol, and thiabendazole were 14.0%, 3.5%, and 5.7%, respectively. The daily intakes of these antifungal agents per person, estimated from their concentrations and the daily consumption of the foods, were 0.000326, 1.89, 11.5, and 23.3 micrograms, respectively, and assuming a body weight of 50 kg, the amounts of these antifungal agents consumed were 0.000013%, 0.15%, 0.12%, and 0.47% of the acceptable daily intake, respectively. These values are similar to the values obtained on the basis of the results of the official inspection in fiscal years 1994 and 1996, except that the amount of diphenyl is much lower (1/100).  相似文献   
182.
Breadmaking properties, such as bread height and specific volume, were improved in bread, made with wheat flour blended with Welsh onion (Allium fistulosum L.) powder, which is high in di‐n‐propyl disulfide (Pro2S2). Breadmaking properties also were improved in bread prepared from wheat flour blended with Pro2S2 alone. Brabender farinographs of Welsh onion powder/wheat flour and Pro2S2/wheat flour showed interesting properties in modifying the width of the tail. Size‐exclusion high performance liquid chromatography of the wheat proteins in the control and blended flours showed a profile of low, medium, and high molecular weight peaks. The area of the high molecular weight peak was larger in the 2 blended flours than in control, indicating this protein was important for the improvement.  相似文献   
183.
Automatic toothbrushing with a commercial dentifrice containing hydroxyapatite (HAP) crystals was performed on the tangential polished surfaces of sound human enamel, mainly consisting of biological apatite similar to HAP, for 10 min in vitro. The X-ray diffraction peaks of HAP, brushite (DCPD), and monetite (DCP) crystals were detected from the dentifrice. After brushing, the enamel surfaces were observed with a scanning electron and a confocal scanning laser microscope. The brushing caused larger abrasive loss and more remarkable roughness of the enamel surfaces following the broad traces of brush bristles and the exposure of prism structures than brushing with a dentifrice containing only DCPD, which we previously reported. We claim that the fine granular-shaped HAP crystals of the dentifrice indicated as an active ingredient for preventing enamel caries possess stronger abrasivity of sound enamel than the DCPD and DCP as abrasives on account of their Mohs hardness values rather than sizes and shapes. The HAP crystals of dentifrices may not occlude the small defects of early caries enamel, but erode them more strongly as an abrasive than the other abrasives.  相似文献   
184.
Research and development of firefighters’ protective clothing relies on a large number of fire disaster experiments in order to assess the thermal performance. It would be substantially advantageous to substitute a virtual numerical experiment for a real one in terms of time, cost and safety. The present article reports the development of an integrated numerical simulator that makes possible the estimation of burn injuries originating from fire disasters. In the simulator, a general-purpose computational fluid dynamics program computes the fluid flow and heat transfer in an in situ fire event, while a one-dimensional program calculates the radiative–conductive heat transfer through the clothing and human skin. A data interface combines the two simulations by loose coupling so as to give the real-time burn injury progress output. The predicted surface heat fluxes and burn degrees agree with experimental measurements reasonably well. Possible numerical error sources are discussed that call for potential improvements in the future.  相似文献   
185.
In this article, we propose MAC protocols based on our infrared-space division transceiver (IR-SDT) for mobile robots. The IR-SDT has eight communication modules, so it can communicate with a maximum of eight other nodes simultaneously. The number of parallel multiple accesses will be improved by using this transceiver and its specialized protocol. In addition, we consider situations in which a packet collision occurs, and propose a protocol that resolves communication conflicts using the signal collision-detection function of IR-SDT. Finally, we consider the performance of these protocols, and discuss the influence of signal collision-detection accuracy.  相似文献   
186.
A mechanism of the phase transition between two modulated structures with different wave vectors was proposed and investigated numerically. The phase transition occurs through the mechanism of nucleation and growth of the new phase. The role of the nucleus is played by an unstable domain wall and the domain of a new low energy phase grows due to the motion of autowaves.  相似文献   
187.
We have previously shown that hippocampal long-term potentiation (LTP), one form of synaptic plasticity that may underlie learning and memory, is attenuated by blocking neuron activity of the basolateral amygdala (BLA). In the present study we investigated the amygdala noradrenergic or cholinergic contribution to hippocampal LTP formation. When propranolol, a beta-adrenoceptor antagonist, was injected into the BLA 10 min before tetanus, the formation of LTP in the perforant path-dentate granule cell synapses was significantly impaired. Scopolamine, a muscarinic cholinergic receptor antagonist, did not affect the formation of LTP. These results suggest that amygdala beta-noradrenergic activity plays a critical role in modulation of hippocampal LTP.  相似文献   
188.
We evaluated the solute atmosphere around a moving dislocation and the dragging stress due to the atmosphere in binary and ternary Al-based alloys in terms of a chemical potential gradient by modifying the method proposed by Yoshinaga et al. In ternary alloys, we analyzed formation of the complex solute atmosphere around a straight edge dislocation and the dragging stress in terms of a misfit parameter of a solute element (positive or negative) and an interaction parameter between solute elements (attractive or repulsive).  相似文献   
189.
Abstracts are not published in this journal This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   
190.
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