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51.
Kumiko Kikuchi Yoko Mizokami Mariko Egawa Hirohisa Yaguchi 《Color research and application》2020,45(2):290-302
In this article, we present an evaluation method for the skin color distribution in the face area. Unlike previous methods that extract a specific area, our method subdivides the entire face into small regions and analyzes detailed, per-frame textures. Our evaluation method for skin color distribution is based on facial feature points and includes segmentation that takes into account the facial skeleton and muscle orientation. The use of facial feature points enables a comparison at relatively equal positions on the face without depending on the shape or size of the individual's face. Our evaluation method is versatile, and as an application, we clarified age-specific features and seasonal variations of facial color distribution. As a result of applying this evaluation method to the facial images of women aged 20 to 78 years, we confirmed that the lightness of the face decreased as age increased. In particular, the decrease in lightness was remarkable in the region along the cheekbone, from the temple to the center of the cheek. Furthermore, we analyzed the seasonal changes of melanin distribution in the face area. This showed that the melanin index increased particularly in the cheekbone area in the summer when the influence of ultraviolet rays became large. Our novel methodology and the data presented in this article will be useful in various fields, such as dermatology, cosmetics, and computer vision. 相似文献
52.
Tomoko Okuyama Jun Shirakawa Kazuki Tajima Yoko Ino Heidrun Vethe Yu Togashi Mayu Kyohara Ryota Inoue Daisuke Miyashita Jinghe Li Nozomi Goto Taiga Ichikawa Shingo Yamasaki Haruka Ohnuma Rie Takayanagi Yayoi Kimura Hisashi Hirano Yasuo Terauchi 《International journal of molecular sciences》2020,21(21)
53.
本文建立了新的卧式振动沸腾床旧砂冷却系统的数学模型,并进行了计算机数字模拟。通过模拟,研究了几个工艺参数对旧砂冷却的影响,并应用能耗指数E和冷却效率η对工厂中使用的旧砂冷却装置进行了评价。 相似文献
54.
Shoji Iwabuchi Prof. Dr. Shin-ichiro M. Nomura Prof. Dr. Yusuke Sato 《Chembiochem : a European journal of chemical biology》2023,24(4):e202200568
Purification of functional DNA nanostructures is an essential step in achieving intended functions because misfolded structures and the remaining free DNA strands in a solution can interact and affect their behavior. However, due to hydrophobicity-mediated aggregation, it is difficult to purify DNA nanostructures modified with hydrophobic molecules by conventional methods. Herein, we report the purification of cholesterol-modified DNA nanostructures by using a novel surfactant-assisted gel extraction. The addition of sodium cholate (SC) to the sample solution before structure folding prevented aggregation; this was confirmed by gel electrophoresis. We also found that adding sodium dodecyl sulfate (SDS) to the sample inhibited structural folding. The cholesterol-modified DNA nanostructures prepared with SC were successfully purified by gel extraction, and their ability to bind to the lipid membrane surfaces was maintained. This method will facilitate the purification of DNA nanostructures modified with hydrophobic molecules and expand their applicability in the construction of artificial cell-like systems. 相似文献
55.
Tetsuya Tanigami Nobuyuki Maruyama Koji Yamazaki Yoko Ichikawa Hiroyuki Nagai Kaori Shimizu 《应用聚合物科学杂志》2002,86(7):1807-1815
An almost fully saponified atactic poly(vinyl alcohol) and an atactic poly(vinyl alcohol‐block‐vinyl acetate) of which degree of saponification is 89 mol % were blended by a solution casting method. The phase structure of the blend film was analyzed by optical microscopy, 13C‐NMR, and differential scanning calorimetry. The most remarkable structure of the blend was composed of cylindrical domains penetrating the film. The swelling behavior of the blend films was also investigated in the dimethylsulfoxide and water mixed solvents to find differences in solubility and diffusion behavior between the matrix and the domain. The cylindrical domains could be selectively dissolved away in water and the film became porous. We tried to change the size of the cylindrical domain with various film preparation conditions. This aimed to turn the film into the useful filter membrane. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1807–1815, 2002 相似文献
56.
Strain-induced ordering of microdomain structures in cross-linked polystyrene-block-polybutadiene-block-polystyrene (SBS) triblock copolymers was examined by the small-angle X-ray scattering technique. To stretch the SBS samples at elevated temperature above the glass transition temperature of polystyrene, polybutadiene blocks were chemically cross-linked in the disordered state. The initial morphology was disorder-like or bicontinuous due to incompletion of microphase separation in the presence of the chemical cross-links. When the cross-linked SBS samples were mechanically stretched at 130 °C and were further annealed for 24 h under a stretched state, the random domain structures ordered gradually and lamellar-like regularity was finally attained. It was found that the ordering proceeded more for the case of the higher strain. 相似文献
57.
Preparation, Structure, and Properties of Thermally and Mechanically Improved Aluminum Titanate Ceramics Doped with Alkali Feldspar 总被引:3,自引:0,他引:3
Masahide Takahashi Masahiro Fukuda Masaaki Fukuda Hisato Fukuda Toshinobu Yoko 《Journal of the American Ceramic Society》2002,85(12):3025-3030
Aluminum titanate (AT) ceramic materials doped with alkali feldspar ((Na0.6 K0.4 )AlSi3 O8 ) have been prepared. These ceramics exhibited high sinterability, large resistance to thermal decomposition, and large flexure strength. The existence of liquid-phase feldspar at sintering temperatures promoted the formation of AT ceramics as the sintering agent. It was considered that silicon ions substituting for aluminum ions at the surface of AT crystal grains lowered the surface energy and hindered the diffusion of Ti4+ and Al3+ , giving rise to the large resistance to thermal decomposition. As a result, doping with alkali feldspar was found to effectively improve the mechanical and thermal properties of AT ceramics. 相似文献
58.
Takashi Hayakawa Hideo Orita Masao Shimizu Katsuomi Takehira Arnfinn G. Andersen Kiyoshi Nomura Yusuke Ujihira 《Catalysis Letters》1992,16(4):359-371
The catalytic activity of LaCoO3–-based mixed oxides for the oxidative coupling of methane has been tested by TPR and cyclic reaction. Characterization has been done by XRD, TGA and Mössbauer spectrometry. It is likely that the perovskite-crystal structure containing hypervalent metal ions has an important role and that unique structural oxygen species in the perovskite contribute to the partial oxidation of methane. 相似文献
59.
Nomura SM Tsumoto K Hamada T Akiyoshi K Nakatani Y Yoshikawa K 《Chembiochem : a European journal of chemical biology》2003,4(11):1172-1175
Functional protein synthesis was observed in cell-sized lipid vesicles following encapsulation of a gene-expression system. Expression of rsGFP (red-shifted green fluorescent protein) within individual vesicles was observed by fluorescence microscopy. Interestingly, at the early stage of the reaction, the expression efficiency inside the vesicle was remarkably higher than that in the solution outside. The synthesized rsGFP in individual vesicles is safe from attack by proteinase K added to the external aqueous solution. Studies on cell-sized vesicles expressing protein should contribute to a fundamental understanding of certain aspects of living systems and will be useful for practical applications, such as the construction of microreactors. 相似文献
60.
Chemical mimicry is an effective strategy when signal receivers recognize and discriminate models by relying on chemical cues. Some aphid enemies mimic the cuticular chemicals of aphids through various means thus avoiding detection and attack by aphid-tending ants. However, because ants have been reported to learn the chemical signatures of aphids in order to distinguish the aphids, the efficacy of chemical mimicry is predicted to depend on the experience of the ants that had tended aphids. The present study tested this hypothesis using two predator species: larvae of the green lacewing Mallada desjardinsi, and larvae of the ladybeetle Scymnus posticalis. Lacewing larvae carry the carcasses of aphids on which they have preyed upon their backs, and these function via chemical camouflage to reduce the aggressiveness of aphid-tending ants toward the larvae. Ladybeetle larvae reportedly produce a covering of wax structures, and their chemicals appear to attenuate ant aggression. We examined whether the behavior of the ant Tetramorium tsushimae toward these predators changed depending on their aphid-tending experience. Ants moderated their aggressiveness toward both predators when they had previously tended aphids, indicating that chemical mimicry by both aphid predators is dependent on previous experience of the ants in tending aphids. Chemical mimicry by the predators of ant-tended aphids is therefore considered to exploit learning-dependent aphid recognition systems of ants. 相似文献