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71.
Dietary exposure to acrylamide in a group of Japanese adults based on 24-hour duplicate diet samples
Junko Kawahara Yazhi Zheng Miho Terui Akiko Shinohara Kaori Uyama Miyuki Yoneyama 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2019,36(1):15-25
Acrylamide is a probable human carcinogen and known human neurotoxin that can be generated in food through heating. Using a mathematical modelling approach, our previous study estimated long-term average dietary exposure to acrylamide in the Japanese people; however, the validity of these estimates remained unknown. Here, we aimed to obtain a more accurate estimate of acrylamide exposure that would reflect the usual practice of heat processing and consumption of foods in the population. We collected duplicate diet samples and dietary records during 24 h from a group of Japanese adults. A total of 110 duplicate diet samples were analysed for acrylamide by LC-MS/MS. Data from individual dietary records were used to examine the association between dietary acrylamide exposure and consumption of selected food groups (e.g., coffee, tea, confectioneries, and vegetables prepared at high temperature [deep-frying, stir-frying, sautéing, and baking]). Of the 110 homogenised diet samples, 108 contained detectable levels of acrylamide. Dietary exposure to acrylamide ranged from 8 to 1582 ng/kg body weight (bw)/day, with the mean value of 215 ng/kg-bw/day and median value of 143 ng/kg-bw/day. This mean value was higher than the value we previously estimated for Japanese adults using a mathematical approach. Multiple linear regression analysis showed log dietary acrylamide exposure was significantly associated with consumption of coffee and vegetables prepared at high temperature during 24-hr of sampling (adj. R2 = 0.250, p < 0.001). We revealed significant difference in dietary acrylamide exposure between participants who had coffee and vegetables prepared at high temperature (median, 169 ng/kg-bw/day; range, 35–1224 ng/kg-bw/day, n = 42) and those who had none of them (median, 75 ng/kg-bw/day; range, 8–311 ng/kg-bw/day, n = 15) (Steel-Dwass test, p < 0.05). 相似文献
72.
Sulfidation treatment of copper-containing plating sludge towards copper resource recovery 总被引:1,自引:0,他引:1
The present study is concerned with the sulfidation treatment of copper-containing plating sludge towards copper resource recovery by flotation of copper sulfide from treated sludge. The sulfidation treatment was carried out by contacting simulated or real copper plating sludge with Na(2)S solution for a period of 5 min to 24 h. The initial molar ratio of S(2-) to Cu(2+) (S(2-) to Me(2+) in the case of real sludge) was adjusted to 1.00, 1.25 or 1.50, while the solid to liquid ratio was set at 1:50. As a result, it was found that copper compounds were converted to various copper sulfides within the first 5 min. In the case of simulated copper sludge, CuS was identified as the main sulfidation product at the molar ratio of S(2-) to Cu(2+) of 1.00, while Cu(7)S(4) (Roxbyite) was mainly found at the molar ratios of S(2-) to Cu(2+) of 1.50 and 1.25. Based on the measurements of oxidation-reduction potential, the formation of either CuS or Cu(7)S(4) at different S(2-) to Cu(2+) molar ratios was attributed to the changes in the oxidation-reduction potential. By contrast, in the case of sulfidation treatment of real copper sludge, CuS was predominantly formed, irrespective of S(2-) to Me(2+) molar ratio. 相似文献
73.
Akiko Hayashi Dr. Ken-ichi Haruna Haruna Sato Dr. Kenichiro Ito Dr. Chisato Makino Dr. Takuhiro Ito Dr. Kensaku Sakamoto 《Chembiochem : a European journal of chemical biology》2021,22(1):120-123
Expansion of the amino-acid repertoire with synthetic derivatives introduces novel structures and functionalities into proteins. In this study, we improved the antigen binding of antibodies by incorporating halogenated tyrosines at multiple selective sites. Tyrosines in the Fab fragment of an anti-EGF-receptor antibody 059–152 were systematically replaced with 3-bromo- and 3-chlorotyrosines, and simultaneous replacements at four specific sites were found to cause a tenfold increase in the affinity toward the antigen. Structure modeling suggested that this effect was due to enhanced shape complementarity between the antigen and antibody molecules. On the other hand, we showed that chlorination in the constant domain, far from the binding interface, of Rituximab Fab also increased the affinity significantly (up to 17-fold). Our results showed that antigen binding is tunable with the halogenation in and out of the binding motifs. 相似文献
74.
75.
This paper deals with the reliability considerations on a redundant system consist of two subsystems connected in series, in which they have a similar warm-standby subsystem, respectively. And these four subsystems are composed of several identical units in parallel redundancy, respectively and are connected with switching devices each other.The purpose of this paper is to attain the following two subjects; (1) to utilize the surviving units at any switch-over point of time, as many as possible, making use of the switching devices as mensioned above, and (2) to deal with various complex redundant systems with or without switching devices, simultaneously.In these considerations we have obtained the reliability function and mean time to system failure (MTSF) of this system. 相似文献
76.
77.
The crystallinity, solubility, degree of swelling, and hygroscopicity of the blends of syndiotactic-rich (st-PVA) and atactic poly(vinyl alcohols) (at-PVA) were studied. The crystallinity of the blends increased with increasing annealing temperature and that of the blends annealed at 200°C was larger than that of at-PVA. In the 200°C annealed blends containing st-PVA about 50%, the insoluble fraction in boiling water was larger than the fraction of st-PVA in each blend. The soluble fraction for the blend containing 75% st-PVA was 1.7%. The moisture regain of the blends was less than that of at-PVA. 相似文献
78.
Lymphocyte blastogenesis in hairless descendants of Mexican hairless dogs was examined using the following mitogens: phytohemagglutinin (PHA-M), Concanavalin A (Con A), lipopolysaccharide (LPS) and pokeweed mitogen (PWM). Blastogenetic responses to these mitogens were measured by glucose consumption test (GCT) and compared with those of haired beagle dogs. The response to PHA-M was significantly less in the hairless dogs than in the beagles. No significant differences in the responses to Con A, PWM and LPS were recognized. These results indicated T-cell dysfunction in the hairless dogs, coinciding with our previous work showing reduction of the delayed-type hypersensitivity reaction and early degeneration of the thymus. 相似文献
79.
Hisashi Sugiyama Keisuke Ebata Akiko Mizushima Kazuo Nate 《Polymer Engineering and Science》1989,29(13):863-867
A new class of alkali-developable positive excimer laser (KrF) resists is described. Novel α-diazoacetoacetates derived from aliphatic polyfunctional alcohols were synthesized. These compounds undergo photolysis upon deep UV exposure to yield carboxylic acids, and exhibit excellent bleaching effects. Some of them, especially those having steroid skeletons, act as effective dissolution inhibitors. The composites prepared from these compounds and poly(p-hydroxybenzylsilsesquioxane) were used as alkali-developable positive deep UV resists, whose sensitivities depend on the number of photoactive groups in one photoactive molecule. Imaging results of KrF excimer laser projection printing are presented. 相似文献
80.
Shoko Hira Akiko Matsumoto Ken Kihara Sakuichi Ohtsuka 《Journal of the Society for Information Display》2019,27(7):409-426
The mutual understanding of color‐normal observers (CNOs) and color‐defective observers (CDOs) is now essential because personal color information display environments have been widely adopted. However, existing tools for CDOs offer only color discrimination; they fail to support color impression (ie, saturation and contrast). Therefore, we need a novel tool that offers help in distinguishing opponent colors, while preserving color saturation. We introduce two key techniques for realizing this difficult goal. The former is the repeated sequential display of the original and processed images to support the formation of unified correct percepts that provide discrimination of both red‐green and yellow‐blue opponent colors. One image, ie, original, exhibits correct yellow‐blue but distorted red‐green information for CDOs while the other, ie, processed, provides synthesized distinguishable red‐green but confusable yellow‐blue information for CDOs; here, hue rotation (HR) is useful for advanced users whereas hue blending (HB) is suitable for general. The latter is realized by the real‐time video processing available on smartphones; our algorithms support direct processing of the digital component video signal formats (eg, Y, CR, and CB). Subjective tests suggest that the two above‐mentioned algorithms will, along with embedding a lightweight real‐time dichromatic simulation facility for CNOs, greatly help the mutual understanding of CNOs and CDOs. 相似文献