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991.
GaAs 2.5 Gbps 16 bit MUX/DEMUX LSI's have been successfully developed. DCFL is employed as a basic gate in order to reduce the power dissipation. To avoid the speed degradation caused by using DCFL, various technologies such as 8×2(MUX)/2×8(DEMUX) data conversion processes, a Selector Merged Shift Register, clock overlapping, and a 0.7-μm BPLDD MESFET, have been introduced. Moreover the ECL I/O level interface and single power supply features make it easy to use MUX/DEMUX in optical communication systems. The maximum operating data rate is 3.2 Gbps for both LSI's, and the power dissipation of chips which operates with 2.5 Gbps are as low as 1.3 W for each MUX/DEMUX  相似文献   
992.
Simulated solid propellant slurry containing lead sphere tracers is experimentally cast into a double-circular cylindrical container. During the casting, the temperature and the pressure environment has been mimicked to an actual composite solid propellant casting of solid rocket motors. X-rays are projected on to the slurry flow from two directions and penetration images are recorded by a flat-panel detector and an X-ray image intensifier. By suppressing the mutual interference of the X-rays, the two-directional X-ray photography has been successfully conducted. Using the time series data of the X-ray images from the two directions, the identification of each tracer particle in space and time has been done and their three-dimensional paths have been computed. From these procedures, the flow field or the velocity field inside the slurry flow, which is usually invisible, has been estimated.  相似文献   
993.
A simulation-based scheduling method for minimizing the due-date-deviation is proposed on the basis of the combination of the BFHS (backward/forward hybrid simulation) method and the parameter-space-search-improvement method. A new schedule generation method named the BFHS/type-D is first developed, in which the information generated during the backward simulation is utilized to control operation-onset timings and job priorities in the forward simulation. Then, after investigation of the backward-simulation characteristics, two parameters are proposed to manipulate the simulation process systematically in relation to due-date-deviation. Furthermore, the best schedule with respect to due-date-deviation is searched for on the space spanned by the two parameters. Finally, the effectiveness and efficiency of the proposed method are demonstrated, not only on a simple job-shop model, but also on a practical large-scale system.  相似文献   
994.
995.
The production of highly specific antibodies to 1 alpha,25-dihydroxyvitamin D3 1a utilizing a novel haptenic derivative 2, which was synthesized from 11 alpha,25-dihydroxycholesterol via 21 steps, has been reported. The properties of the obtained antibodies are also described.  相似文献   
996.
A 57-year old man, who had suffered from herpes simplex encephalitis and had been cured without antiviral agents, was admitted to our hospital three years after the encephalitis. He had a complete loss of memory for events subsequent to the encephalitis and a retrograde amnesia for the several years leading up the encephalitis. MRI revealed the abnormalities located in the limbic system, especially the medial portions in the bilateral temporal lobes of the cerebrum were completely destroyed. We consider that this case suggests the specific affinity of herpes simplex virus especially for the medial portions in the temporal lobes of the cerebrum.  相似文献   
997.
Candida meningitis is a growing problem today. We report a 21-day-old male baby who was a victim of Candida albicans meningitis with the initial presentations of fever, mild stiff neck, poor feeding and activity. He had been treated with intravenous antibiotics and ventilator therapy prior to admission Initially, he was treated as a case of bacterial sepsis after admission with intravenous antibiotics. Due to positive cultures of cerebrospinal fluid for Candida albicans twice, intravenous amphotericin B was started from the 13th hospital day and was continued for 38 days. The successive three sets of CSF fungus culture yielded negative results and the patient was doing well without fever. Meanwhile, the brain sonogram revealed normal findings and he was discharged in a stable condition. We report this case and review some literature in an attempt to know more about this unusual disease, which is becoming more frequent as progress in intensive care grows.  相似文献   
998.
We evaluated the antithrombogenicity of 4F-catheters coated with the new antithrombogenic material fluorine-acryl- styrene-urethane-silicone (FASUS) graft-block copolymer by dissecting microscopic and scanning electron microscopic observations. These catheters were temporarily used for the infusa-A-port, which was prepared for the treatment of four patients with bladder cancer. Two heparin-coated catheters were also evaluated. All FASUS-coated catheters contained thrombi consisting of red thrombi and/or fibrin thrombi. Massive red thrombus was seen at the site of curvature of the catheters, 1 cm distal to the tip of the catheter. However, the portion 20 cm distal to the tip of the catheter had no red thrombus, but contained minimal fibrin thrombus or plasma protein. The heparin-coated catheters showed the same findings as the FASUS catheters. The FASUS-coated catheters were not superior in antithrombogenicity to the heparin-coated catheters. It was concluded that the FASUS-coated catheters used in this study seemed to have problems in regard to their preshaped curvature and the material used in catheter. These aspects need to be improved.  相似文献   
999.
Laser recrystallization of p-channel SOI MOSFETs on an undulated insulating layer is demonstrated for SRAMs with low power and high stability. Self-aligned p-channel SOI MOSFETs for loads are stacked over bottom n-channel bulk MOSFETs for both drivers and transfer gates. A sufficient laser power assures the same leakage currents between SOI MOSFETs fabricated on an undulated insulating layer in memory cell regions and on an even insulating layer in field regions. The on/off ratio of the SOI MOSFETs is increased by a factor of 104, and the source-drain leakage current is decreased by a factor of 10-102 compared with those of polysilicon thin-film transistors (TFTs) fabricated by using low-temperature regrowth of amorphous silicon. A test 256-kb SRAM fabricated this technology shows improved stand-by power dissipation and cell stability. The process steps can be decreased to 83% of those TFT load SRAMs if both the peripheral circuit and memory cells are made with p-channel SOI and n-channel bulk MOSFETs  相似文献   
1000.
We found a novel metalloproteinase, which has high activity at low temperatures and in the presence of organic solvents, in the culture supernatant of a marine bacterium, Vibrio sp. T1800. The metalloproteinase, named vimelysin, was purified from the culture supernatant by three column chromatographies. About 150 mg of purified vimelysin was obtained from 3.3 liters of the culture supernatant with a high yield of 57%. The purified vimelysin showed a single protein band on SDS-PAGE with molecular weight of 38,000. The isoelectric point of vimelysin was 4.3 by isoelectric focusing. The optimum pH of vimelysin was pH 8.0 or pH 6.5 using casein or furylacryloyl-glycyl-leucine amide (FAGLA) as substrates, respectively. The optimum temperature of vimelysin was 50 degrees C when casein was used as a substrate, but it was 15 degrees C when FAGLA was used as a substrate. Interestingly, vimelysin activity was completely retained after 48 h of incubation at 25 degrees C in the presence of 50% ethanol. Moreover, vimelysin showed 40% activity of the control even in the presence of 10% ethanol, while thermolysin showed only 5% activity under the same conditions.  相似文献   
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