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1.
Effects of microwave heating on the oxidative stability ofd-tocopherols were studied in relation to the production of fatty acids in oils. During microwave heating, the stability of tocopherols decreased in the orderδ>β>γ>α. This order did not depend on the types of ethyl esters of fatty acids or oils present. But, the shorter the chainlength and the lower the degree of unsaturation of the fatty acid ethyl esters, the greater was the reduction in amount of individual tocopherols. A similar tendency was observed when tocopherol-stripped vegetable oils, with equimolar mixtures of tocopherols added, were treated under the same conditions. The reduction in tocopherols became greater with increasing levels of free fatty acids.  相似文献   
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Aluminium (Al) levels of 90 food samples were investigated. Nineteen samples contained Al levels exceeding the tolerable weekly intake (TWI) for young children [body weight (bw): 16 kg] when consuming two servings/week. These samples were purchased multiple times at specific intervals and were evaluated for Al levels. Al was detected in 27 of the 90 samples at levels ranging from 0.01 (limit of quantitation) to 1.06 mg/g. Of these, the Al intake levels in two samples (cookie and scone mix, 1.3 and 2 mg/kg bw/week, respectively) exceeded the TWI as established by European Food Safety Authority, although the level in the scone mix was equivalent to the provisional TWI (PTWI) as established by Joint Food and Agriculture Organization of the United Nations/World Health Organization Expert Committee on Food Additives. The Al levels markedly decreased in 14 of the 19 samples with initially high Al levels. These results indicated reductions in the Al levels to below the PTWI limits in all but two previously identified food samples.  相似文献   
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Migration from multi-layer laminated film pouches intended for retort foods was investigated through HPLC analysis with a fluorescence detector, and measurements of residue on evaporation, consumption of potassium permanganate and total organic carbon. HPLC analysis revealed that the levels of migrants in oil and the water which were heated in the pouches (121 degrees C, 30 min) were ten times of those in the corresponding official simulants under the official conditions; n-heptane (25 degrees C, 60 min), and water (95 degrees C, 30 min). Bisphenol A diglycidyl ether and related compounds were found in the oil and the water heated in the pouches, as well as in the simulants. These compounds were thought to have been present in the adhesive between the laminated films, and migrated through the food-contact film of the package. Consumption of potassium permanganate and residue on evaporation of the heated water were ten times of those of the water simulant, while the total organic carbon level of the heated water was several-hold greater than that of the water simulant. In addition, migrant levels per surface area of the pouch were one-fourth of the concentrations per content volume of the pouch. Since compliance with the legal limits is evaluated based on the concentration per surface area, real migration into foods would be underestimated by a factor of another four.  相似文献   
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Vision-based sensor for real-time measuring of surface traction fields   总被引:2,自引:0,他引:2  
The desire to reproduce and expand the human senses drives innovations in sensor technology. Conversely, human-interface research aims to allow people to interact with machines as if they were natural objects in a cybernetic, human-oriented way. We wish to unite the two paradigms with a haptic sensor as versatile as the sense of touch and developed for a dual purpose: to improve the robotic capability to interact with the physical world, and to improve the human capability to interact with the virtual world for emerging applications with a heightened sense of presence. We designed a sensor, dubbed GelForce, that acts as a practical tool in both conventional and novel desktop applications using common consumer hardware. By measuring a surface traction field, the GelForce tactile sensor can represent the magnitude and direction of force applied to the skin's surface using computer vision. This article is available with a short video documentary on CD-ROM.  相似文献   
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We developed a robotic arm for a master-slave system to support "mutual telexistence", which realizes remote dexterous manipulation tasks and close physical communication with other people using gestures. In this paper, we describe the specifications of the experimental setup of the master-slave arm to demonstrate the feasibility of the mutual telexistence concept. We developed the master arm of a telexistence robot for interpersonal communication. The last degree of the 7-degree-of-freedom slave arm is resolved by placing a small orientation sensor on the operator's arm. This master arm is made light and impedance control is applied in order to grant the operator as much freedom of movement as possible. For this development stage, we compared three control methods and confirmed that the impedance control method is the most appropriate to this system.  相似文献   
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Studies in animals have suggested that lactic acid bacteria alleviate allergic diseases, however, little information is available on their clinical effect on allergy in humans. Thus, we examined the efficacy of orally administered Lactobacillus acidophilus strain L-92 (L-92) on perennial allergic rhinitis. In a randomized, double-blind, placebo-controlled clinical trial, 49 patients with perennial allergic rhinitis were randomized to receive either 100 mL of heat-treated fermented milk containing L-92 (n = 25) or acidified milk without lactic acid bacteria (placebo; n = 24) for 8 wk. The severity of symptoms was evaluated based on the changes in the scores of clinical symptoms. Oral administration of milk fermented with L-92 resulted in a statistically significant improvement of nasal symptom-medication scores. Ocular symptom-medication scores of patients in the L-92 intervention group tended to improve compared with those in the placebo group. In addition, clear decreases of the scores of swelling and color of the nasal mucosa were observed in the L-92 intervention group at 6 and 8 wk after the start of ingestion of fermented milk. There were no significant differences in serum antihouse dust mite immunoglobulin E levels nor in T helper type 1/T helper type 2 ratio between the 2 groups. These results suggest that oral administration of L-92 can alleviate the symptoms of perennial allergic rhinitis, however, statistically significant changes were not shown in blood parameters.  相似文献   
10.
The enzyme catalyzing conversion of N alpha-benzyloxycarbonyl-L-aminoadipic-delta-semialdehyde (N alpha-Z-L-AASA) to N alpha-benzyloxycarbonyl-L-aminoadipic acid (N alpha-Z-L-AAA) in Rhodococcus sp. AIU Z-35-1 was identified, and its characteristics were revealed. This reaction was catalyzed by a dehydrogenase with a molecular mass of 59 kDa. The dehydrogenase exhibited enzyme activity on not only N alpha-Z-L-AASA but also N alpha-Z-D-AASA and short chain aliphatic aldehydes, but not on aromatic aldehydes and alcohols. The apparent Km values for N alpha-Z-L-AASA, N alpha-Z-D-AASA and NAD+ were estimated to be 3.8 mM, 14.1 mM and 0.16 mM, respectively. The NH2 terminal amino acid sequence of this enzyme exhibited a similarity to those of a piperidein-6-carboxylate dehydrogenase from Streptomyces clavuligerus and a putative dehydrogenase from Rhodococcus sp. RHA 1, but not to those of other microbial aldehyde dehydrogenases.  相似文献   
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