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121.
Kawasaki K Yoshida T Tarui M Nakagawa H Yano H Ishikawa O Hata T 《Physical review letters》2004,93(10):105301
We have investigated the transition phenomena of superfluid 3He in thin 0.8 microm slabs with a cw-NMR method. We found that, just below the phase-transition temperature, only the A phase appeared at any pressure. At lower temperatures, the phase transition to the B phase occurred between 0.3 and 2.74 MPa. We obtained a universal critical thickness delta as a function of pressure. When the reduced slab thickness, d/xi(T), is smaller than delta, only the A phase becomes stable. 相似文献
122.
We propose an optical system to implement rewritable transparent broad-band color filters. The filter consists of a linear variable filter and a liquid crystal spatial light modulator in which an expected filter function is written. A time-integrated intensity image was taken while the filter was passing the lens aperture of a CCD camera. The averaged norm error between the implemented and the expected filter functions was about 5.4#x0025;. The system was applied to spectral estimation in a two-dimensional color image. 相似文献
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We propose a fiber-optic non-mechanical scanning laser Doppler velocimeter (LDV) with directional discrimination of the velocity component using a single transmission path. The LDV uses a polarization maintaining fiber (PMF) as the transmission path between the main body and probe. Two beams with different frequencies induced by acousto-optic modulators (AOMs) are transmitted to the probe as two orthogonal polarization modes of the PMF. The measurement position is axially scanned using gratings in the probe and the change in wavelength. The functions of the scan and directional discrimination are demonstrated experimentally. 相似文献
125.
Hiroko Nakayama Kanae Hata Izumi Matsuoka Liqing Zang Youngil Kim Djongchi Chu Lekh Raj Juneja Norihiro Nishimura Yasuhito Shimada 《Molecules (Basel, Switzerland)》2020,25(24)
(1) Background: The obesity epidemic has been drastically progressing in both children and adults worldwide. Pharmacotherapy is considered necessary for its treatment. However, many anti-obesity drugs have been withdrawn from the market due to their adverse effects. Instead, natural products (NPs) have been studied as a source for drug discovery for obesity, with the goal of limiting the adverse effects. Zebrafish are ideal model animals for in vivo testing of anti-obesity NPs, and disease models of several types of obesity have been developed. However, the evidence for zebrafish as an anti-obesity drug screening model are still limited. (2) Methods: We performed anti-adipogenic testing using the juvenile zebrafish obesogenic test (ZOT) and mouse 3T3-L1 preadipocytes using the focused NP library containing 38 NPs and compared their results. (3) Results: Seven and eleven NPs reduced lipid accumulation in zebrafish visceral fat tissues and mouse adipocytes, respectively. Of these, five NPs suppressed lipid accumulation in both zebrafish and 3T3-L1 adipocytes. We confirmed that these five NPs (globin-digested peptides, green tea extract, red pepper extract, nobiletin, and Moringa leaf powder) exerted anti-obesity effects in diet-induced obese adult zebrafish. (4) Conclusions: ZOT using juvenile fish can be a high-throughput alternative to ZOT using adult zebrafish and can be applied for in vivo screening to discover novel therapeutics for visceral obesity and potentially also other disorders. 相似文献
126.
Yuuki Hata Tomoya Kojima Tohru Maeda Toshiki Sawada Takeshi Serizawa 《Macromolecular bioscience》2020,20(9)
Multicomponent systems for self‐assembled molecular gels provide huge opportunities to generate collective or new functions that are not inherent in individual single‐component gels. However, gelation tends to require careful and complicated procedures, because, among a myriad of kinetically trapped structures related to the degree of mixing of multiple components over a wide range of scales, from molecular level to macroscopic scale, a limited number of structures that exhibit the desired function need to be constructed. This study presents a simple method for the construction of double‐network (DN) hydrogels with improved stiffness composed of crystalline cellulose oligomers and gelatin. The pH‐triggered self‐assembly of cellulose oligomers leads to the formation of robust networks composed of crystalline nanofibers in the presence of dissolved gelatin, followed by cooling to allow for the formation of soft gelatin networks. The resultant DN hydrogels exhibit improved stiffness; the improvement in gel stiffness with double networking is comparable to that of previously reported DN hydrogels produced via a time‐consuming enzymatic reaction. 相似文献
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Phosphoenolpyruvate was synthesized in high yield by a simple procedure starting from pyruvic acid and dimethyl trimethylsilyl phosphite through trimethylsilylation, bromination, and the Perkow reaction. 相似文献