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71.
Fujisawa H. Nakamura M. Takai Y. Koshikawa Y. Matano T. Narui S. Usuki N. Dono C. Miyatake S. Morino M. Arai K. Kubouchi S. Fujii I. Yoko H. Adachi T. 《Solid-State Circuits, IEEE Journal of》2005,40(4):862-869
This paper describes three circuit techniques for a DDR1/DDR2-compatible chip architecture designed for both high-speed and high-density DRAMs: 1) a dual-clock input-latch scheme, which reduces the excessive timing margin for random input commands by using a pair of latch circuits controlled by dual-phase one-shot clock signals, achieves a 0.9-ns reduction in cycle time from 3.05 to 2.15 ns; 2) a hybrid multi-oxide output buffer reduces the area penalty of the output buffer caused by compatible chip design from 1.35% to 0.3%; and 3) a quasi-shielded distributed data transfer scheme enables a 2.6-ns reduction in access time to 10.25 ns in both 2-b and 4-b prefetch operations. By using these techniques, we developed a 175.3-mm/sup 2/ 1-Gb SDRAM that operates as an 800-Mb/s/pin DDR2 or 400-Mb/s/pin DDR1. 相似文献
72.
Kenji Kitaoka Hiromitsu Kozuka Toshinobu Yoko 《Journal of the American Ceramic Society》1998,81(5):1189-1196
Lead lanthanum zirconate titanate (PLZT, (Pb,La)(Zr,-Ti)O3 ) ceramic fibers were prepared by the sol-gel method from a solution of lead acetate trihydrate, lanthanum isopropoxide, zirconium n -propoxide, and titanium isopropoxide that contained 2-methoxyethanol as the solvent. The sols obtained from the solution were concentrated at 156°-174°C for 2 h. Concentration at higher temperatures resulted in more-viscous sols of higher specific gravities. The concentration resulted in the formation of spinnable sols, which had viscosities >105 mPas and exhibited Newtonian flow properties. These spinnable sols were formed to be so stable that no change in viscosity and spinnability was observed for more than three months when stored in a sealed container at room temperature. Gel-to-ceramic fiber conversion was investigated by means of X-ray diffractometry, infrared spectroscopy, and thermal analysis. Single-phase perovskite PLZT ceramic fibers 5-200 μm in diameter and >20 cm in length were obtained. Scanning electron microscopy (SEM) observation and Brunauer-Emmett-Teller (BET) measurement showed that heat treatment of the fibers at a lower rate resulted in the formation of fibers of denser microstructure. Although the SEM image of the cross section of the fibers revealed a relatively dense microstructure and a laser beam could be transmitted through a fiber 6 mm in length, BET measurement of the fibers indicated that the fibers had more than a few percent of open porosities, and scattering of light was observed in the laser-beam guiding test. 相似文献
73.
The effects of infusion of trieicosapentaenoyl-glycerol emulsion on extravascular lung water during myocardial ischemia and reperfusion in dogs 总被引:2,自引:0,他引:2
Toshio Izuoka Yutaka Kimura Tomohito Hamazaki Teruhiro Tamura Shuji Kitashiro Tetsuro Sugiura Toshimitsu Jikuhara Toshiji Iwasaka 《Lipids》1997,32(1):109-114
To test the effects of eicosapentaenoic acid (EPA) infusion on pulmonary edema induced by coronary ligation and reperfusion,
extravascular lung water (EVLW) was measured in situ by the thermal-dye double indicator dilution method in dogs. In the control group of five dogs, 30 mL of a 10% soybean oil
emulsion was infused through a leg vein. One hour after infusion, the left anterior descending coronary artery below the first
diagonal branch was ligated for 15 min and then reperfused for 30 min. In the EPA group, six dogs were similarly treated with
an emulsion of a 10% trieicosapentaenoyl-glycerol (90% pure). EVLW, pulmonary capillary wedge pressure, mean pulmonary artery
pressure, mean blood pressure, and cardiac index were measured before and 15 min after coronary ligation, and 15 min and 30
min after coronary reperfusion. There were no significant differences in the hemodynamic indices between the two groups. EVLW
significantly increased up to two times of baseline during coronary ligation in the control group (P< 0.05) and more during reperfusion (P<0.01), whereas EVLW did not increase in the EPA group. In conclusion, EPA inhibited EVLW accumulation and may be useful for
ameliorating one of the ischemia-reperfusion-induced complications, pulmonary edema. 相似文献
74.
At present, in the field of intelligent transport systems (ITSs), research on in-vehicle communications (VCs), intervehicle communications (IVCs), road-to-vehicle communications (RVCs), etc. continues. All information communication technology, especially radio communications technology, was applied. In this paper, in order to minimize the costs of equipment and simplify the design, equipment, structure of VC, IVC, and RVC for traffic jam area, the authors proposed to utilize a wireless Bluetooth technology system. The whole proposed system is connected to the Internet backbone, and provided some access point (AP) areas, the Internet can be accessed from inside the vehicle, and information, such as news and weather information, can be downloaded. It is also possible to know traffic information for each AP area by accessing a data center server. 相似文献
75.
Tomohito Hamazaki Shigeki Sawazaki Tetsuro Nagasawa Yoko Nagao Yuko Kanagawa Kazunaga Yazawa 《Lipids》1999,34(1):S33-S37
The purpose of the present research was to clarify the effect of docosahexaenoic acid (DHA) intake on behavior and plasma catecholamines (CA). In Study 1, 42 students took either DHA-rich oil capsules containing 1.5–1.8 g DHA/d or control oil capsules containing 97% soybean oil plus 3% of another fish oil for 3 mon in a double-blind fashion. They took a psychological test (PF Study) at the start and end of the study. This study started at the end of summer vacation and ended just before the final exams. In the control group, external aggression (aggression against others) in PF Study was significantly increased at the end of the study as compared with that measured at the start (+8.9%), whereas it was not significantly changed in the DHA group (?1.0%). In a similar double-blind study (Study 2), we measured external aggression under nonstressful conditions. External aggression slightly decreased in the control group, whereas there were no significant changes in the DHA group. In Study 3 with 14 students, plasma CA were measured at the start and end of capsule administration period of 2 mon. Subjects were under continuous stress of the final exams that lasted throughout the whole study period. The ratio of plasma epinephrine to norepinephrine concentrations was significantly increased in the DHA group (78%), whereas it stayed at the same level in the control group. In Study 4, mice were fed either DHA-deficient diet or -sufficient diet for 4 wk, and their rearing frequency (an anxiety index) was measured. In the DHA-sufficient group, the rearing frequency was significantly less than in the other group. These effects of DHA intake may be applied to people in an attempt to ameliorate stress-related diseases. 相似文献
76.
Hori Tetsuya; Moriyama Hideaki; Kawaguchi Jitsutaro; Hayashi-Iwasaki Yoko; Oshima Tairo; Tanaka Nobuo 《Protein engineering, design & selection : PEDS》2000,13(8):527-533
A temperature-jump (T-jump) time-resolved X-ray crystallographictechnique using the Laue method was developed to detect small,localized structural changes of proteins in crystals exposedto a temperature increase induced by laser irradiation. In achimeric protein between thermophilic and mesophilic 3-isopropylmalatedehydrogenases (2T2M6T), the initial structural change uponT-jump to a denaturing temperature (~90°C) was found tobe localized at a region which includes a ß-turn and aloop located between the two domains of the enzyme. A mutant,2T2M6T-E110P/S111G/S113E, having amino acid replacements inthis ß-turn region with the corresponding residues ofthe thermophilic enzyme, showed greater stability than the originalchimera (increase of Tm by ~10°C) and no T-jump-inducedstructural change in this region was detected by our method.These results indicate that thermal unfolding of the originalchimeric enzyme, 2T2M6T, is triggered in this ß-turn region. 相似文献
77.
Ishiwata H Abe Y Kubota H Kawasaki Y Takeda Y Maitani T Nishijima M Fukasawa Y 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2002,43(1):49-56
The mean concentrations and daily intake of four antifungal agents were estimated based on the results of an analysis of 7,005 samples of food obtained in official inspections by Japanese local governments in fiscal year 1998. The mean concentration of diphenyl was 0.0004% of the allowable limit, and those of imazalil, o-phenylphenol, and thiabendazole were 14.0%, 3.5%, and 5.7%, respectively. The daily intakes of these antifungal agents per person, estimated from their concentrations and the daily consumption of the foods, were 0.000326, 1.89, 11.5, and 23.3 micrograms, respectively, and assuming a body weight of 50 kg, the amounts of these antifungal agents consumed were 0.000013%, 0.15%, 0.12%, and 0.47% of the acceptable daily intake, respectively. These values are similar to the values obtained on the basis of the results of the official inspection in fiscal years 1994 and 1996, except that the amount of diphenyl is much lower (1/100). 相似文献
78.
Uematsu Y Ogimoto M Kabashima J Suzuki K Kaneko R Funayama K Haneishi N Yasuno T Ogino S 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2005,46(4):133-138
Migration from multi-layer laminated film pouches intended for retort foods was investigated through HPLC analysis with a fluorescence detector, and measurements of residue on evaporation, consumption of potassium permanganate and total organic carbon. HPLC analysis revealed that the levels of migrants in oil and the water which were heated in the pouches (121 degrees C, 30 min) were ten times of those in the corresponding official simulants under the official conditions; n-heptane (25 degrees C, 60 min), and water (95 degrees C, 30 min). Bisphenol A diglycidyl ether and related compounds were found in the oil and the water heated in the pouches, as well as in the simulants. These compounds were thought to have been present in the adhesive between the laminated films, and migrated through the food-contact film of the package. Consumption of potassium permanganate and residue on evaporation of the heated water were ten times of those of the water simulant, while the total organic carbon level of the heated water was several-hold greater than that of the water simulant. In addition, migrant levels per surface area of the pouch were one-fourth of the concentrations per content volume of the pouch. Since compliance with the legal limits is evaluated based on the concentration per surface area, real migration into foods would be underestimated by a factor of another four. 相似文献
79.
Yasuo Kagawa Mami Hiraoka Yukiko Miyashita-Hatano Madoka Shishido-Oki Mamiko Yoshida Susumu Kondou Mika Sugiura Kazumi Sawakami-Kobayashi Masaaki Takahashi Hideji Tajima Masafumi Yohda 《Journal of Bioscience and Bioengineering》2010,110(4):505-508
A low-cost and simple on-site technique for genotyping single nucleotide polymorphisms (SNPs) was developed. The technique is based on allele-specific primer PCR and the recently developed bead arrays in a single tip technique. The performance of the method was verified by genotyping four SNPs that correlate with cardiovascular diseases. 相似文献
80.
Ayako Sakai Yoko Yamakoshi Naoki Miyata 《Fullerenes, Nanotubes and Carbon Nanostructures》1999,7(5):743-756
Cell transformation in vitro is a model of carcinogenesis in vivo. Two-stage transformation assay increases the sensitivity of cells to chemicals and permits detection of carcinogens acting as initiating agents. [60]Fullerene (C60) was cytotoxic in BALB/3T3 cells when it was irradiated by visible light, but not without light irradiation. Under conditions when C60 was cytotoxic, it acted as an initiating agent for cell transformation, but it did not act as a complete transforming agent. the initiating activity of visible-light-irradiated C60 was statistically significant in a modified two-stage transformation assay including a procedure for replating cells treated by C60 and light, but it was equivocal in the standard two-stage transformation assay. 相似文献