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61.
This study examined how tocopherol retention is affected by the presence or absence of food coatings, and also tested the measurement of fluorescent substance levels in cooking oil to evaluate oil deterioration. Potato slices were tempura-fried (with a coating) or french-fried (without a coating). The three tocopherol isomers decreased with heating time, and better retention was found in the tempura process. The decomposition rates of tocopherol were in the order γ> δ ≥α for the three isomers for both processes over repeated fryings. The fluorescence of frying oil increased 15-and 17-fold after tempura-and french-frying, respectively, for 32 consecutive times. Changes in the amounts of tocopherol and the fluorescence correlated well with the changes found by the chemiluminescent intensity and five conventional methods of oil quality measurement. These results indicated that tocopherol retention is affected by the food coating, and that measurements of vitamin E loss and fluorescence increase in oil should be useful for assessing the progressive deterioration of frying oil with its repeated usage.  相似文献   
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We investigated the actual factor determining the softening effect of a fabric softener. The adsorption area of the softener on model cotton cloths and yarns was identified using bromophenol blue. There was almost no softener at the cross-points of the yarns in the cloth samples or in the inner part of the yarns. The softening performance was better when there was less softener at the cross-points of the yarns than when the yarns were evenly covered by the softener. Thus we conclude that the presence of softener at the cross-points of yarns is not a vital factor in the softening effect. In addition, more softener was found on the outer part of the yarn than the inner part, indicating gradation in the adsorption pattern of the softener. Thus, we propose that more softener is adsorbed on the exposed part of the yarn in a cloth, and the formation of a hydrogen-bonding network containing bound water is inhibited, thus softening the outer part of the yarn. However, the presence of a small amount of softener in the inner part of the yarn preserves the hydrogen-bonding network. Favorable elasticity, or bounce, of the yarns and cloth is realized when an appropriate amount of softener is used. Excess softener would reach the inner part of the yarn, reducing the diameter of the core part of the yarn, making the cloth appear wilted.  相似文献   
65.
The establishment of more efficient approaches for developmental neurotoxicity testing (DNT) has been an emerging issue for children's environmental health. Here we describe a systematic approach for DNT using the neuronal differentiation of mouse embryonic stem cells (mESCs) as a model of fetal programming. During embryoid body (EB) formation, mESCs were exposed to 12 chemicals for 24 h and then global gene expression profiling was performed using whole genome microarray analysis. Gene expression signatures for seven kinds of gene sets related to neuronal development and neuronal diseases were selected for further analysis. At the later stages of neuronal cell differentiation from EBs, neuronal phenotypic parameters were determined using a high-content image analyzer. Bayesian network analysis was then performed based on global gene expression and neuronal phenotypic data to generate comprehensive networks with a linkage between early events and later effects. Furthermore, the probability distribution values for the strength of the linkage between parameters in each network was calculated and then used in principal component analysis. The characterization of chemicals according to their neurotoxic potential reveals that the multi-parametric analysis based on phenotype and gene expression profiling during neuronal differentiation of mESCs can provide a useful tool to monitor fetal programming and to predict developmentally neurotoxic compounds.  相似文献   
66.
Fluorescent nanodiamond (FND) is attracting much attention as a bioimaging agent because of its inherent biocompatibility and superior optical properties (e.g., excellent photostability and far‐red emission). However, for practical use in life science research, some issues such as higher brightness and ease of bioconjugation have to be solved. Here, it is shown that the 100‐nm FND particles fabricated by using nitrogen‐rich type Ib diamonds and high‐energy proton irradiation are highly fluorescent and readily functionalizable with proteins for biological applications. In the first approach, acid‐treated FND is noncovalently coated with glycoproteins or neoglycoproteins (i.e., proteins chemically modified with multiple sugar residues) for targeting hepatocytes via carbohydrate receptors. In the second approach, FND is first PEGylated and then covalently conjugated with streptavidin, to which biotin‐labeled antibodies of interest are linked. High targeting specificity of the bioconjugated FND is demonstrated with the human hepatoma cell line, HepG2, and breast cancer cell lines, ASB145‐1R, MCF‐7, and MDA‐MB‐231 cells. These approaches should be widely applicable to a variety of situations for specific targeting and labeling of cells.  相似文献   
67.
The herbicide-tolerant genetically modified Roundup Ready canola (Brassica napus) line RT73 has been approved worldwide for use in animal feed and human food. However, RT73 Brassica rapa lines derived from interspecific crosses with RT73 B. napus have not been approved in Japan. Here, we report on a novel system using individual kernel analyses for the qualitative detection of RT73 B. rapa in canola grain samples. We developed a duplex real-time polymerase chain reaction (PCR) method to discriminate B. napus and B. rapa DNA using scatter plots of the end-point analyses; this method was able to discriminate a group comprising B. rapa and Brassica juncea from a group comprising B. napus, Brassica carinata, and Brassica oleracea. We also developed a duplex real-time PCR method for the simultaneous detection of an RT73-specific sequence and an endogenous FatA gene. Additionally, a DNA-extraction method using 96-well silica-membrane plates was developed and optimized for use with individual canola kernels. Our detection system could identify RT73 B. rapa kernels in canola grain samples enabling the accurate and reliable monitoring of RT73 B. rapa contamination in canola, thus playing a role in its governmental regulation in Japan.  相似文献   
68.
Transparent zinc oxide (ZnO) films were coated on seed layers prepared by the sol–gel method by chemical solution deposition method. Firstly, seed layers were prepared from zinc acetate and monoethanolamine, 2-methoxyethanol by the sol–gel method on a silicon substrate or a slide glass. Next, the substrate coated with a seed layer was immersed in zinc nitride solution with hexamethylenetetramine, and ZnO films were obtained. The transmittance of the ZnO films depended on the morphology and crystallinity of the seed layers. When the seed layer were dried on a hot plate, the seed layer had flat surface and transparent ZnO film could be obtained on the seed layers dried at temperatures above 200 °C. When the seed layer was prepared from zinc acetate dihydrate dried in a petri dish, the seed layer were smooth without cracks and the transparent ZnO films were obtained at temperature below 100 °C.  相似文献   
69.
Vestibular schwannomas are the most common tumor at the common cerebellopontine angle, followed by meningiomas. Differentiation of these tumors is critical because of the different surgical approaches required for treatment. Recent studies have demonstrated the utility of amide proton transfer (APT)-chemical exchange saturation transfer (CEST) imaging in evaluating malignant brain tumors. However, APT imaging has not been applied in benign tumors. Here, we explored the potential of APT in differentiating between schwannomas and meningiomas at the cerebellopontine angle. We retrospectively evaluated nine patients with schwannoma and nine patients with meningioma who underwent APT-CEST MRI from November 2020 to April 2022 pre-operation. All 18 tumors were histologically diagnosed. There was a significant difference in magnetization transfer ratio asymmetry (MTRasym) values (0.033 ± 0.012 vs. 0.021 ± 0.004; p = 0.007) between the schwannoma and meningioma groups. Receiver operative curve analysis showed that MTRasym values clearly differentiated between the schwannoma and meningioma groups. At an MTRasym value threshold of 0.024, the diagnostic sensitivity, specificity, positive predictive value, and negative predictive values for MTRasym were 88.9%, 77.8%, 80.0%, and 87.5%, respectively. Our results demonstrated the ability of MTRasym values on APT-CEST imaging to discriminate patients with schwannomas from patients with meningiomas.  相似文献   
70.
Characteristics of CR-39 plastic containing chlorinated compounds such as HCB and DCD have been studied using relativistic heavy ions from the LBL Bevalac. These results are compared with those of pure CR-39, focusing in particular on etching properties and on whether a penetrating etch hole is produced along each particle path by a long duration etch. The relation between the reduced track etch rate and the etchant concentration for CR-39 containing HCB is quite different from that of pure CR-39. Dilute etchants gives much higher track sensitivities than do more concentrated solutions in a wide range of REL. Since type HCB/DCD CR-39 loss its sensitivity in the interior of the bulk material for low REL produced by 2.1 GeV/n Ne ions, penetrating etch holes are not produced along the particle paths after a heavy etching.  相似文献   
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