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111.
Junichi Karasawa Taku Aoyama Takeshi Kijima Eiji Natori Tatsuya Shimoda 《Integrated ferroelectrics》2013,141(1):137-145
A high-pressure annealing was applied to a post-annealing process for sol-gel derived PZT thin films. The squareness of D-E hysteresis curves changes depending on both total pressure and oxygen concentration. Moreover, the change follows the product of the total pressure and the oxygen concentration, which correspond to oxygen partial pressure PO2. Where the PO2 is higher than 0.03 MPa, few of the squareness of the hysteresis curve are excellent. The squareness of the hysteresis curves dramatically improve as the PO2 decreases. Where the PO2 is lower than 0.01 MPa, the squareness deteriorates slightly. These changes in the D-E hysteresis curves are thought to be explained by the generation of lead and oxygen vacancies as a function of the PO2. 相似文献
112.
Dr. Haruka Hiraoka Dr. Zhaoma Shu Dr. Bao Tri Le Dr. Keiko Masuda Dr. Kosuke Nakamoto Lyu Fangjie Dr. Naoko Abe Dr. Fumitaka Hashiya Dr. Yasuaki Kimura Dr. Yoshihiro Shimizu Prof. Dr. Rakesh N. Veedu Prof. Dr. Hiroshi Abe 《Chembiochem : a European journal of chemical biology》2021,22(24):3437-3442
We have found that antisense oligonucleotides and siRNA molecules modified with repeat structures of disulfide units can be directly introduced into the cytoplasm and exhibit a suppressive effect on gene expression. In this study, we analyzed the mechanism of cellular uptake of these membrane-permeable oligonucleotides (MPONs). Time-course analysis by confocal microscopy showed that the uptake of MPONs from the plasma membrane to the cytoplasm reached 50 % of the total uptake in about 5 min. In addition, analysis of the plasma membrane proteins to which MPONs bind, identified several proteins, including voltage-dependent anion channel. Next, we analyzed the behavior of MPONs in the cell and found them to be abundant in the nucleus as early as 24 h after addition with the amount increasing further after 48 and 72 h. The amount of MPONs was 2.5-fold higher than that of unmodified oligonucleotides in the nucleus after 72 h. We also designed antisense oligonucleotides and evaluated the effect of MPONs on mRNA exon skipping using DMD model cells; MPONs caused exon skipping with 69 % efficiency after 72 h, which was three times higher than the rate of the control. In summary, the high capacity for intracytoplasmic and nuclear translocation of MPONs is expected to be useful for therapeutic strategies targeting exon skipping. 相似文献
113.
Kazuki Yamaoka Ryota Oikawa Dr. Naoko Abe Dr. Kosuke Nakamoto Dr. Fumiaki Tomoike Dr. Fumitaka Hashiya Dr. Yasuaki Kimura Prof. Dr. Hiroshi Abe 《Chembiochem : a European journal of chemical biology》2021,22(23):3273-3276
Chemical ligation reaction of DNA is useful for the construction of long functional DNA using oligonucleotide fragments that are prepared by solid phase chemical synthesis. However, the unnatural linkage structure formed by the ligation reaction generally impairs the biological function of the resulting ligated DNA. We achieved the complete chemical synthesis of 78 and 258 bp synthetic DNAs via multiple chemical ligation reactions with phosphorothioate and haloacyl-modified DNA fragments. The latter synthetic DNA, coding shRNA for luciferase genes with a designed truncated SV promoter sequence, successfully induced the expected gene silencing effect in HeLa cells. 相似文献
114.
Kazama Haruna Ohata Yuto Ishiguri Yoichi Ono Hajime Mori Naoki Yoshinaga Naoko 《Journal of chemical ecology》2022,48(5-6):583-587
Journal of Chemical Ecology - TXIB (2,2,4-trimethyl-1,3-pentanediol diisobutyrate), a common plasticizer, inhibits the peach fruit moth, Carposina sasakii from ovipositing on young apple fruits.... 相似文献
115.
The influence of dietary excess (5%) L-histidine on serum and liver lipids was examined in rats. Feeding a histidine-excess
diet for 3, 6, 14 or 30 days caused growth retardation, hepatomegaly and decreased liver lipids throughout the period of the
experiment. Hypercholesterolemia was observed after feeding a histidine-excess diet for 6 days; then serum cholesterol continuously
increased for 30 days. Serum triglyceride on day 30 in rats fed the histidine-excess diet showed a significant decrease compared
to rats fed the basal diet. Serum phospholipids of rats fed the histidine-excess diet for 7 or 14 days showed a significant
increase compared to rats fed the basal diet. When rats were fed a basal, histidine-excess or cholesterol-supplemented diet
(0.5% and 1.0% cholesterol) for 6 days, the distribution of serum high density (HDL), low density (LDL) and very low density
lipoprotein cholesterol in rats fed the histidine-excess diet was similar to that of rats fed the basal diet, whereas LDL-cholesterol
increased and HDL-cholesterol decreased in rats fed the cholesterol-supplemented diet. 相似文献
116.
117.
Kawahara Yoshihiro Aoyama Tomonori Morikawa Hiroyuki 《Telecommunication Systems》2004,25(3-4):353-370
This paper presents a scalable peer-to-peer communication architecture suitable for supporting networked virtual environments that does not require costly dedicated servers or special infrastructure such as multicasting. Entities establish an overlay network based on the distance between the entities. As message exchange is handled directly by unicast between nearest-neighbor entities, the communication overhead is kept low. The proposed architecture is highly scalable and suitable for online applications such as massively multiplayer online role-playing games with hundreds of thousands of participants, where the dominant factor affecting scalability and performance is the overhead associated with exchange of update messages between users. 相似文献
118.
119.
D. Shimura R. Sekikawa K. Kotani M. Uekawa Y. Maeno K. Aoyama H. Sasaki T. Takamori K. Masuko S. Nakaya 《Photonics Technology Letters, IEEE》2006,18(16):1738-1740
We have succeeded in developing a low-cost bidirectional optical subassembly chip using a silicon microlens for fiber-to-the-home application. The main optical elements of the bidirectional function were automatically aligned and integrated on a silicon optical bench. The cost of subassembly was markedly lowered both by reducing the part number and simplifying the assembly process. The prototype bidirectional optical component was successfully fabricated on the basis of the proposed chip. A receiver minimum sensitivity of -28.5 dBm was experimentally demonstrated even at 75 /spl deg/C. 相似文献
120.