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71.
K Kawabata K Mitsui T Uno K Tamura K Tsurugi 《Canadian Metallurgical Quarterly》1999,259(1-2):112-119
The GTS1 gene product, Gts1p, has pleiotropic effects on the timing of budding, cell size, heat tolerance, sporulation and the lifespan of the yeast Saccharomyces cerevisiae. In this study, we found (using the yeast two-hybrid system) that Gts1p forms homodimers throughout the 18-amino acid region 296-313 which has considerable similarity to a region downstream of the Walker nucleotide-binding motif A of some ATP-binding cassette (ABC) transporters. The region contains two aspartic acid residues at 301 and 310 preceded by hydrophobic amino acid residues, and Gts1p with an Asp310 to Ala substitution showed considerably reduced homodimerization, as shown by the two-hybrid assay. Overexpression of the point-mutated Gts1p did not efficiently induce the Gts1p-related phenotypes described above, suggesting that the homodimerization of Gts1p is required for it to function in vivo. The C-terminal cytoplasmic domain of the yeast ABC transporters Mdl1p (multidrug resistance-like transporter) and Ycf1p (yeast cadmium factor or glutathione S-conjugate pump) bound to Gts1p in the two-hybrid system, and the heterodimerization activity of the Gts1p with the Asp301 to Ala substitution was more affected than the Gts1p with the Asp310 to Ala substitution. Overexpression of GTS1 considerably reduced, and disruption of GTS1 slightly decreased, cellular resistance to cycloheximide, cadmium, cisplatin and 1-chloro-2,4-dinitrophenol, which (except for cycloheximide) are all substrates of Ycf1p. These results suggest that Gts1p interacts with some ABC transporters through the binding site overlapping that of homodimerization and modulates their activity. 相似文献
72.
Ryota Kato Yasunari Yoshitomi Taro Asada Masayoshi Tabuse 《Artificial Life and Robotics》2010,15(1):10-16
The purpose of this study was to develop a system for communication between a human and a computer generated (CG) character
to make him or her more peaceful and cheerful. Nonverbal communication using such things as facial expression, a nod, or a
hand gesture is very important for reciprocal communication between humans. In this study, an image registered by infrared
rays which describes the thermal distribution of the face and neck has been used to develop a system for communication between
a human and a CG character. The CG character can synchronize its nod with a person’s nod by predicting his or her nod angle.
The measured feature parameter is input to a fuzzy algorithm system to obtain the nod angle of a person in front of an infrared
camera, and then a moving-average model is used to predict the nod angle of the person. The average error of the nod angle
obtained by the system has been estimated as about 5°. The CG character nods its head, not only when the human nods his or
her head, but also when the human shakes his or her head to the left or right. 相似文献
73.
74.
Hitoshi Tanaka Morimasa Tanimoto Akira Matsuda Takeo Uno Masaaki Kurihara Shoji Shiga 《Journal of Electronic Materials》1999,28(11):1216-1223
Pb-free solderable surface finishing is essential to implement Pb-free solder assembly in order to meet with the growing demand
of environmental consciousness to eliminate Pb from electronic products. Two types of widely applicable Pb-free surface finishing
technologies are developed. One is the multilayer-system including Pd with Ni undercoat. Heat-resistance of Pd enables whole-surface-plating
on to leadframe before IC-assembling process. The other is the double-layer-system with low-melting-point-materials, for example,
thicker Sn underlayer and thinner Sn-Bi alloy overlayer, dilutes Sn-Bi alloy’s defects of harmful reactivity along with substrate
metal and mechanical brittleness with keeping its advantages of solder-wettability and no whisker. 相似文献
75.
Masayoshi Kamiya Hiroaki Ikeda Shigenobu Shinohara 《International Journal of Communication Systems》2001,14(5):477-485
This paper describes a low‐cost version of a full‐duplex optical fibre analogue/digital data transmission link whose practical implementation is simplified by using a pair of laser diodes, each having a built‐in photodiode for monitoring the laser output power, and its application to vibration test data transmission. The transmission link sends digital data of up to 9600 bps in one direction, and analogue data of DC to 100 kHz and image data specified by an NTSC colour video signal in the opposite direction, all at the same time through one GI optical fibre. Being simple in configuration and stable against noise, this type of link has a variety of applications within factory, home and offices. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
76.
Micrometer‐sized polymer particles with encapsulated ultraviolet (UV) absorbent, fluorescent agent, and blue pigment were successfully prepared by microsuspension polymerization utilizing the Self‐assembling of Phase Separated Polymer method. The particles were characterized by optical microscope and particle size distribution analysis, and they were evaluated on their usefulness for cosmetic using UV spectrometry, colorimetry, VISIA? Evolution, and bioassay. The capsule particles had multifunctional properties, which are very attractive in the cosmetic field, especially in whitening, brightening, the improvement of face‐texture, and less noticeable pores in face, as well as the protection from UV. Moreover, bioactivities of the particles under the UV irradiation, which were examined with the films prepared from capsule components, revealed not only makeup effect but also the activation of human epidermal keratinocytes. The results suggest the importance of blue light in the field of cosmetics. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
77.
Jun-Woo ParkKazuki Yoshida Naoki TachikawaKaoru Dokko Masayoshi Watanabe 《Journal of power sources》2011,196(4):2264-2268
The physicochemical and electrochemical properties of the binary ionic liquid (IL), lithium bis(trifluoromethylsulfonyl)amide (LiTFSA) dissolved in N,N-diethyl-N-methyl-N-(2-methoxyethyl)ammonium bis(trifluoromethylsulfonyl)amide (DEMETFSA), were investigated. The ionic conductivity of the binary IL decreased with an increase in LiTFSA concentration. The self-diffusion coefficients of Li+, DEME+, and TFSA− dissolved in the IL were measured by using the pulsed-field-gradient spin-echo (PGSE) NMR method. The self-diffusion coefficient of each ionic species was also found to decrease with increasing concentration of LiTFSA. The limiting current density in the IL electrolyte was evaluated by chronoamperometry using symmetric Li|IL|Li cell. The results suggest that the diffusion process of Li(I) in the IL dominates the limiting current density in the cell. The highest limiting current density is achieved at a concentration of 0.64 mol dm−3 of LiTFSA. 相似文献
78.
Shiro Seki Takeshi Kobayashi Nobuyuki Serizawa Yo Kobayashi Katsuhito Takei Hajime Miyashiro Kikuko Hayamizu Seiji Tsuzuki Takushi Mitsugi Yasuhiro Umebayashi Masayoshi Watanabe 《Journal of power sources》2010,195(18):6207-6211
The physicochemical and electrochemical properties of three 1-alkyl-2,3,5-trimethylpyrazolium cation-based room-temperature ionic liquids with various alkyl chain lengths were investigated. The temperature dependences of density, viscosity, and ionic conductivity were obtained by precise measurements. Electrolyte properties of these room-temperature ionic liquids were also examined from the viewpoint of their uses in lithium secondary batteries ([LiCoO2 positive electrode|electrolyte|lithium metal negative electrode]). It was found that the alkyl chain length affects the charge–discharge performances of cells. 相似文献
79.
The purpose of this study is to create a natural fiber-reinforced fully green composite with excellent toughness. By treating
ramie plied yarns in a high concentration alkali solution, the reinforcements were mercerized. Results of tensile tests showed
that unidirectional composites using mercerized ramie yarns exhibited two to three times larger fracture strain, without a
marked decrease in strength, than composites using untreated yarns. In addition, mercerization for the ramie yarns brings
a better interfacial strength to the composites. Laminated composites using mercerized ramie yarns also showed approximately
twice larger impact energy than composites using untreated yarns. Thus, mercerization for natural fibers is expected for application
to mechanical materials requiring a high toughness. 相似文献
80.
Hydrogels that contain phosphate groups in side chains were studied for their usefulness in drug‐delivery soft contact lenses (SCLs). Naphazoline, a model drug having a cationic group, was incorporated into an SCL because of its phosphate groups and was released over a period of about 14 h. For the SCL, the naphazoline content was equivalent to the phosphate group content. It is suggested that drug‐delivery SCLs can be designed to contain the needed amount of a drug through the choice of the ionic group for the ligand. Furthermore, the SCL having amide groups and phosphate groups had high transparency and an unchanged shape. It is suggested that amide groups and phosphate groups must be introduced into the polymer in equimolar amounts to give the necessary polymer–drug interaction. Therefore, hydrogels having a drug‐delivery system were synthesized by the inclusion of a phosphate group and an amide group. These hydrogels are also applicable to SCL materials. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 731–735, 2005 相似文献