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21.
A fast modular multiplication method based on precomputation is proposed for use in public-key cryptosystems. The proposed method can compute the Montgomery reduction TR1 mod N only through additions. Furthermore, this is 6.4 times faster than the Montgomery method implemented in modular reduction with a 512 bit modulus when 2.1 MB of memory is used. This memory size is also only 1/4 of that required in the method proposed by Takenaka et al 相似文献
22.
Matano T. Takai Y. Takahashi T. Sakito Y. Fujii I. Takaishi Y. Fujisawa H. Kubouchi S. Narui S. Arai K. Morino M. Nakamura M. Miyatake S. Sekiguchi T. Koyama K. 《Solid-State Circuits, IEEE Journal of》2003,38(5):762-768
A 1-Gb/s/pin 512-Mb DDRII SDRAM has been developed using a digital delay-locked loop (DLL) and a slew-rate-controlled output buffer. The digital DLL has a frequency divider for DLL input, performs at an operating frequency of up to 500 MHz at 1.6 V, and provides internal clocking with 50% duty-cycle correction. The DLL has a current-mirror-type interpolator, which enables a resolution as high as 14 ps, needs no standby current, and can operate at voltages as low as 0.8 V. The slew-rate impedance-controlled output buffer circuit reduces the output skew from 107 to 10 ps. This SDRAM was tested using a 0.13-/spl mu/m 126.5-mm/sup 2/ 512-Mb chip. 相似文献
23.
Cardiac arrest occurred in a male Labrador Retriever dog weighing 27.8 kg during induction to anesthesia. Immediately after the failure of resuscitation by the external cardiac compression, thoracotomy was performed and open chest direct current (DC) counter shocks were applied with routine emergency medications. Then the dog recovered consciousness. Although cardiac rhythm just after resuscitation was sinus tachycardia with paroxysmal supraventricular tachycardia, multifocal ventricular arrhythmia occurred 2 hr after resuscitation. This arrhythmia might be the result from reversible cardiac lesions due to DC counter shock. 相似文献
24.
Identification of SYS1 as a Host Factor Required for Shiga Toxin-Mediated Cytotoxicity in Vero Cells
Chisato Sakuma Tsuyoshi Sekizuka Makoto Kuroda Kentaro Hanada Toshiyuki Yamaji 《International journal of molecular sciences》2021,22(9)
Shiga toxin (STx) or Vero toxin is a virulence factor produced by enterohemorrhagic Escherichia coli. The toxin binds to the glycosphingolipid globotriaosylceramide (Gb3) for its entry, and causes cell death by inhibiting ribosome function. Previously, we performed a loss-of-function screen in HeLa cells using a human CRISPR knockout (KO) library and identified various host genes required for STx-induced cell death. To determine whether this library targeted to the human genome is applicable to non-human primate cells and to identify previously unrecognized factors crucial for STx-induced cell death, we herein performed a similar screen in the African green monkey kidney-derived Vero C1008 subline. Many genes relevant to metabolic enzymes and membrane trafficking were enriched, although the number of enriched genes was less than that obtained in the screening for HeLa cells. Of note, several genes that had not been enriched in the previous screening were enriched: one of these genes was SYS1, which encodes a multi-spanning membrane protein in the Golgi apparatus. In SYS1 KO Vero cells, expression of Gb3 and sphingomyelin was decreased, while that of glucosylceramide and lactosylceramide was increased. In addition, loss of SYS1 inhibited the biosynthesis of protein glycans, deformed the Golgi apparatus, and perturbed the localization of trans-Golgi network protein (TGN) 46. These results indicate that the human CRISPR KO library is applicable to Vero cell lines, and SYS1 has a widespread effect on glycan biosynthesis via regulation of intra-Golgi and endosome–TGN retrograde transports. 相似文献
25.
A New Process to Make a Porous PTFE Structure from Aqueous PTFE Dispersion with the Help of Hydrogel
A novel method to make a porous material having relatively large cell diameter (200–300 m), which consisted of mainly poly(tetrafluoroethylene) (PTFE), was developed from aqueous PTFE dispersion by using the characteristics of hydrogel with the addition of carbon nanofiber (CNF). The porous material was produced as follows: firstly, an aqueous agar gel containing PTFE and CNF was prepared; secondly, the gel was freeze-dried; thirdly, the dried gel was heat-treated at 400°C where the agar was almost decomposed and PTFE became molten. The porous material showed electric conductivity (about 50 ), high porosity (about 96 vol%), and relatively uniform cell structures without shrinkage during freeze drying and heat treatment. While the method without CNF resulted in large shrinkage during heat treatment, meaning that CNF prevented the shrinkage. It was explained by the idea that the existence of rigid CNF, which was dispersed in the cell wall, prohibited the shrinkage of PTFE during heat treatment. It was unexpectedly found by SEM analysis that the porous materials had another macro-porous structure inside the cell wall, suggesting that the developed materials had a double porous structure. 相似文献
26.
In Situ Observation of Phase Separation of a Barium Borate Melt in a Stable Immiscibility Region under Microgravity 总被引:1,自引:0,他引:1
Satoru Inoue Akio Makishima Hiroyuki Inoue Kohei Soga Tomoya Konishi Tomoyoshi Asano Yuu Ishii Masato Koyama 《Journal of the American Ceramic Society》1997,80(9):2413-2417
The precipitation of droplets was directly observed on a BaO–B2 O3 melt in a drop shaft experiment. This is the first time that precipitation of droplets has been observed in a 4.5 s drop test. The melt film of 4BaOz96B2 O3 (mol%) held on a platinum wire loop was heated above the critical tem-perature to produce uniformity and was cooled down to the phase separation temperature range. Phase separation of the melt was observed directly with a video camera. The IR image of the melt was simultaneously detected with a CCD array and was converted into a two-dimensional thermograph. 相似文献
27.
Summary A study was made of the degree of splitting of coconut and soybean oils by the Twitchell process at 35±0.1°C. with no shaking
or stirring, using an agent consisting mainly of tetrabutyl naphthalene sulfonic acid with water or dilute sulfuric acid.
The degree of splitting was greater with sulfuric acid than with water. In general, the degree of splitting of soybean oil
was greater when the sulfonic acid was dissolved in the oil layer than when it was in water. The reverse was true with coconut
oil. Although addition of glycerol had no effect on the degree of splitting, addition of glacial acetic acid to the coconut
oil system decreased fat splitting to a considerable extent. Addition of coconut fatty acids to the coconut oil system had
little effect, but soybean fatty acids added to the soybean oil system markedly increased the degree of splitting.
For the first time it has been demonstrated that, at 35±0.1°C., splitting of a fat by the Twitchell process occurs in a stepwise
way. Coconut oil in contact with 1N sulfuric acid containing the sulfonic acid, corresponding to 1% by the weight of the oil, was about 90% split in 15 to 30
days, depending on the area of contact of the two layers. The diglyceride concentration reached a maximum during the early
days of the reaction and then decreased somewhat. Monoglyceride concentration appeared to reach a maximum more slowly and
then continued at that level as the concentrations of free fatty acids and glycerol steadily increased.
Presented at the symposia on fat of the Chemical Society of Japan, Nov. 10, 1954, and Nov. 8, 1955, Nagoya, Japan; and the
8th annual meeting of the Chemical Society of Japan, Apr. 2, 1955, Tokyo, Japan. 相似文献
28.
Shinnosuke Miyauchi Yasuo Hattori Toshiyuki Takamatsu Yoshio Sorimachi 《应用聚合物科学杂志》1992,44(3):377-381
A method to generate a porous region near the surface of a polymer is suggested. In this method the region near the surface is swollen by immersing the polymer for a short time in a solvent. Subsequently, the polymer is introduced in a nonsolvent (for the polymer) that is, however, miscible with the solvent. The formation of the porous region is a result of (1) the swelling accompanied by the disentanglement of the surface molecular chains, and the dissolution of some of them during the immersion in the solvent, and (2) the rapid extraction of the solvent from the swollen region by the nonsolvent. The porous surface provides a matrix into which a second incompatible monomer can be polymerized so that the two otherwise incompatible polymers can adhere to one another. 相似文献
29.
Takashi Mitamura Hiroyuki Ogino Hidehiko Kobayashi Toshiyuki Mori Hiroshi Yamamura 《Journal of the American Ceramic Society》1993,76(8):2127-2128
Preparation of BaLa2 O4 , Ba3 ,Y4 O9 , Ba ,In2 O5 , and Ba3 Ga2 O6 powders and their sintering were investigated in Ar or air. These sintered bodies with perovskite-related structure were synthesized by reaction sintering, using mixed powders in the atomic ratios of Ba/La = 1, Ba/Y = 0.75, Ba/In = 1, and Ba/Ga = 1.5. The order-disorder transition temperatures of the BaLa2 O4 , Ba3 Y4 O9 , Ba2 In2 O5 , and Ba3 Ga2 O6 sintered bodies were 270°, 350°, 880°, and 123Oo C, respectively. It was found that the temperatures were influenced by the ionic radius of cations in B sites, and the transition temperatures decreased with increasing ionic radius. 相似文献
30.
The crystallization kinetics of the running filament in melt spinning have been studied for three cases: isothermal crystallization of an isotropic melt, non-isothermal crystallization of an isotropic melt, and non-isothermal crystallization of a non-isotropic melt. Both the temperature and the orientation dependences of nucleation rate and growth rate are estimated for polypropylene. Calculated curves for non-isothermal crystallization of a non-isotropic melt with partial high orientation closely approximate the experimental data. In particular, the experimental data are best explained by crystallization with two-dimensional growth. The crystallization processes in melt spinning may be governed by localized molecular orientation of the supercooled melt in the initial stage. 相似文献