著者
Kazuki Nakanishi Macoto Kikuchi
出版者
THE PHYSICAL SOCIETY OF JAPAN
雑誌
Journal of the Physical Society of Japan (ISSN:00319015)
巻号頁・発行日
vol.75, no.6, pp.064803, 2006-06-15 (Released:2009-08-27)
参考文献数
17
被引用文献数
4

We investigate aggregation mechanism of two proteins in a thermodynamically unambiguous manner by considering the finite size effect of free energy landscape of HP lattice protein model. Multi-self-overlap-ensemble Monte Carlo method is used for numerical calculations. We find that a dimer can be formed spontaneously as a thermodynamically stable state when the system is small enough. It implies the possibility that the aggregation of proteins in a cell is triggered when they are confined in a small region by, for example, being surrounded by other macromolecules. We also find that the dimer exhibits a transition between unstable state and metastable state in the infinite system.
著者
Reiichiro TSUCHIYA Takumi TANAKA Gen HAYASE Kazuyoshi KANAMORI Kazuki NAKANISHI
出版者
公益社団法人 日本セラミックス協会
雑誌
Journal of the Ceramic Society of Japan (ISSN:18820743)
巻号頁・発行日
vol.123, no.1441, pp.714-718, 2015-09-01 (Released:2015-09-01)
参考文献数
17
被引用文献数
5

Conventionally, commercialized spherical silicone powders, such as silicone resin powder [INCI: POLYMETHYLSILSESQUIOXANE (PMSQ beads)] and silicone rubber powder [INCI: DIMETHICONE/VINYL DIMETHICONE CROSSPOLYMER (DVDC beads)], have been formulated into cosmetics for soft and smooth feeling. Due to the low crosslink density, silicone rubber powder shows soft touch and high oil absorption. However, it is too agglomerative to be formulated into powder foundation. In this work, we have developed the novel soft touch spherical silicone beads made from methyltrimethoxysilane (MTMS) and dimethyldimethoxysilane (DMDMS), using a surfactant, cetyltrimethylammonium chloride (CTAC). The preparation procedure of the novel silicone beads requires only homogeneous mixing and includes no other complicated operations. The 29Si NMR and TG measurements indicate that DMDMS is randomly incorporated into the methylsiloxane network. The particle size of the beads can be controlled by the concentration of urea as well as by the stirring speed in the sol–gel reaction. By carefully adjusting these parameters, the size of the beads has been optimized for the use in make-up cosmetics. It was revealed by various evaluation measurements that the novel silicone beads exhibit unique characteristics, such as softness, low oil absorption, high transparency and light diffusion effects.