IMPACT LOADING AND HAIR BREAKAGE 257 (2) A. C. Brown and J. A. Swift, Hair breakage: The scanning electron microscope as a diagnostic tool, ]. Soc. Cosmet. Chem., 26, 289-299 (1975). (3) Y. K. Karnath and H.-D. Weigmann, Fractography of human hair,]. Appl. Polym. Sci., 27, 3809-3833 (1982). (4) Y. K. Karnath, S. B. Hornby, and H.-D. Weigmann, Mechanical and fractographic behavior of Ne­ groid hair,]. Soc. Cosmet. Chem., 35, 21-43 (1984). (5) J. Alan Swift, The mechanics of fracture of human hair, Int.]. Connet. Sci., 21, 227-239 (1999). (6) N. P. Khumalo et al., What is normal black African hair? A light and scanning electron-microscopic study,]. Am. Acad. Dermatol., 43, 814 (2000). (7) D. C. Fleming, Modeling Delamination Growth in Composites Using MSC. Dytran, Florida Institute of Technology, Department of Mechanical and Aerospace Engineering (dfleming@fit.edu). (8) K. Q. Qiu et al., Salient shear bands and second phase addition interactions of bulk metallic glass matrix composites, Metallurgical and Materials Transactions A 34, A, 1147-1154 (2003).

]. Cosmet. Sci.J 57, 259-260 (May/June 2006) Abstracts Journal of the Society of Cosmetic Chemists Japan Vol. 40, No. 1, 2006* A Study on Neck Skin Physiology and Its Application to value between the cheek (heavily sun-exposed area) and Development of Cosmetics back (not sun-exposed area) . From these results it was considered that not only intrinsic aging but also Naomi Kunizawa•2, Yuji Masuda•2, Keiko Takada•3, photo-aging affected the neck skin. We developed the Shinji Inomata•3, Mutsuko Oki•4, Takayuki Oomura•4, prototype of cosmetics corresponding to neck skin Takanari Tsuda•4, Motoji Takahashi•2 physiology based on these results, and evaluated the effectiveness of the prototype product by a consumer test Shiseido Life Science Research Center•2, 2-2-1, including skin measurement for 4 weeks. After treatment, Hayabuchi, Tsuzuki-ku, Yokohama 224-8558, Japan - water content increased, and it gave satisfaction in the skin Shiseido l\1aterial Science Research Center+3, 2-2-1, color brightness, skin elasticity and skin texture Hayabuchi, Tsuzuki-ku, Yokohama 224-8558, Japan - improvements for almost all volunteers. It was concluded Shiseido Product Development Center+4, 2-2-1, Hayabuchi, that the prototype product was useful in neck skin Tsuzuki-ku, Yokohama 224-8558, Japan treatment. The neck is a sun-exposed area. It seems to show the symptoms of photo-aging as well as facial skin in the Material Design Using Genetic Algorithms and Preparation elderly. However, the physiological study of neck skin has oflnnovative lN-Reflecting Composite hardly been reported. We examined the change of skin physiological properties at a neck site with aging for 61 Ryuichi Inaba, Kazuhisa Takahashi, Shigenori Kumagai women (18 to 69 years old) compared with a cheek site. Water content in stratum corneum (SC) was higher, TEWL Nippon Shikizai, Inc., 5-3-13, Mita, Minato-ku, Tokyo was lower and the turnover rate of SC judged from 108-0073, Japan comeocyte area was slower at the neck site compared with the cheek site. Skin thickness was thinner, skin extensibility Genetic algorithm (GA) , which is one of the methods that and elasticity were higher, skin grooves were deeper, and optimize the combination of facton., was applied to the anisotropy of skin furrows was lower at the neck site than design of a new cosmetic material. GA effectively gives an those at the cheek site. It was shown that the neck was also adequate solution especially when there are huge facton. affected by sunlight but not so much as the cheek from the and infinite combinations among those individual factors. result of gelatinase activity detected in the tape stripped SC. In this work, the lN-Reflecting composite that effectively Skin elasticity decreased with aging at the neck site as well reflects lN light and has high visible light transparency as the cheek site. Fine wrinkles were remarkably increased was chosen as the target material. From GA simulation, a in the direction of Langer's line with aging at the neck. blueprint of the composite was obtained as follows: The Most skin physiological parameten. at the neck showed the multiple la yen. on the core material (mica) should be 27 nm * These abstracts appear as they were originally published. They have not been edited by the Journal of Cosmetic Science. 259