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81.
Fukuda M. Noguchi Y. Motosugi G. Nakano Y. Tsuzuki N. Fujita O. 《Lightwave Technology, Journal of》1987,5(12):1778-1781
In InGaAsP/InP buried heterostructure (BH) lasers, the degradation of BH interface between first- and second-growth step layers can be suppressed by employing the melt back process just before the second-step layer growth. It is confirmed this burying process give more reliable BH lasers than the conventional burying process. From the viewpoint of BH interface degradation, lasers lasing at 1.5 μm, where the melt back process naturally occurs during BH formation, are found to be more reliable than those lasing at 1.3 μm. 相似文献
82.
Okayasu M. Takeshita T. Yamada M. Kogure O. Horiguchi M. Fukuda M. Kozen A. Oe K. Uehara S. 《Electronics letters》1989,25(23):1563-1565
High-power GaInAs strained quantum well lasers with an emission wavelength of 0.98 mu m, suitable for Er/sup 3+/-doped fibre amplifier pumping, have been fabricated. A threshold current of 15 mA and a peak output power as high as 85 mW have been obtained for the ridge waveguide structure with AR/HR facet coating. Highly efficient pumping for the 1.536 mu m signals has been confirmed.<> 相似文献
83.
84.
I Makino M Watanabe N Okamoto N Ohguro M Fukuda K Emi 《Canadian Metallurgical Quarterly》1997,101(9):734-737
We report a case of retinal detachment with Kniest dysplasia for which vitreous surgery was effective. The patient was a 7-year-old female who had the typical ocular and physical findings of this disease. Visual acuity was light perception alone due to a hypermature cataract and bullous retinal detachment. We performed cataract surgery and pars plana vitrectomy, and used silicone oil tamponade. After seven months, the silicone oil was removed, and visual acuity improved to 0.09. We conclude that bullous retinal detachment with Kniest dysplasia can be treated by vitreous surgery in combination with the use of silicone oil tamponade. 相似文献
85.
86.
Mitsuo Fukuda 《Microelectronics Reliability》2000,40(1):27
The failure modes and failure mechanisms in optoelectronic devices, such as laser diodes, Light-emitting diodes, and photodiodes, are reviewed through a historical overview of device reliability and their future reliability is briefly discussed. 相似文献
87.
K Watanabe H Hiraki H Hasegawa T Tanigawa I Emura K Honma H Shibuya T Fukuda T Suzuki 《Canadian Metallurgical Quarterly》1997,47(8):540-546
Endothelin (ET) and its receptor system have been shown to exert various biological effects on different types of cells in addition to their well-known vasoconstrictor activity. Recently ET-1, ET-3 and the ETB receptor have been shown to play an important role in the development of neural crest-derived cells and, in this context, pheochromocytomas have been reported to harbor ET-1. Endothelin-3 or ET receptor subtypes, however, have not been examined in pheochromocytoma and paraganglioma so far. In the present study the immunohistochemical localization of ET-1/big ET-1, ET-3/big ET-3 and the ETA and ETB receptors were investigated to clarify the biological characteristics of these two tumors using 32 pheochromocytomas and 11 extra-adrenal paragangliomas. Endothelin-1/big ET-1 was detected in 19 pheochromocytomas (59%) and eight paragangliomas (72%), while ET-3/big ET-3 was detected in 10 pheochromocytomas (31%) and three paragangliomas (27%). The ETA receptor was found in 21 pheochromocytomas (66%) and in eight paragangliomas (73%), while the ETB receptor was found in 25 pheochromocytomas (78%) and in eight paragangliomas (73%). Normal adrenomedullary cells lacked each antigen examined. Endothelin-immunoreactive tumor cells were distributed focally or in a manner scattered, while receptor-immunostained tumor cells were distributed with a focal pattern for the ETA receptor and with a focal or diffuse pattern for the ETB receptor. Endothelin and its receptor coexisted in the same tumor in 21 of 28 ET-positive pheochromocytomas and in eight of 10 ET-positive paragangliomas. In addition, seven pheochromocytomas and two paragangliomas revealed positivity of the receptor(s) irrespective of the absence of ET-immunoreactivity. In conclusion, ET and its receptor are frequently and concomitantly expressed in the pheochromocytoma and paraganglioma. From the highly frequent expression of this system or the receptor(s), ET-receptor-mediated signal transduction of these tumors concerning growth and/or cell survival is expected, although definite biological significance of this ligand-receptor system in these tumors awaits further investigation. 相似文献
88.
Jennifer L Graef Abbie E Smith Kristina L Kendall David H Fukuda Jordan R Moon Travis W Beck Joel T Cramer Jeffrey R Stout 《Journal of the International Society of Sports Nutrition》2009,6(1):18-7
Background
High-intensity interval training has been shown to be a time-efficient way to induce physiological adaptations similar to those of traditional endurance training. Creatine supplementation may enhance high-intensity interval training, leading to even greater physiological adaptations. The purpose of this study was to determine the effects of high-intensity interval training (HIIT) and creatine supplementation on cardiorespiratory fitness and endurance performance (maximal oxygen consumption (VO2PEAK), time-to-exhaustion (VO2PEAKTTE), ventilatory threshold (VT), and total work done (TWD)) in college-aged men. 相似文献89.
A calculation method for symbol error probability is proposed for multilevel QAM systems. Carrier-to-noise ratio penalties are estimated by this method for seven typical impairment factors, including recovered carrier phase error, timing error, receive filter residual delay, etc. The validity of the method is verified by experiments on penalties caused by recovered carrier phase error and timing error. Based on the new method of analysis, signatures of a 64 QAM modem are estimated theoretically, using a pseudo-two-ray model of multipath fading. The dependence of signatures on the above-mentioned impairment factors is investigated in detail. A qualitative deduction of impairment factors from a measured signature is demonstrated. The measured signature agrees well with a calculated one in which reasonable values of the impairment factors are assumed. 相似文献
90.
Raymond L.D. Whitby Takahiro Fukuda Toru Maekawa Stuart L. James Sergey V. Mikhalovsky 《Carbon》2008,46(6):949-956
The fabrication of buckypaper from unfunctionalised multi-walled carbon nanotubes (MWCNTs) without the aid of surfactants or surface modification techniques is accomplished through a novel and quick frit compression method. The dimensions can be controlled through the size of the syringe housing and the through the mass of carbon nanotubes added. Their thicknesses are typically much larger than surfactant-cast buckypaper and range from 120 μm up to 650 μm; buckypaper with thicknesses larger than 500 μm we call buckydiscs. Buckypaper and buckydiscs are mechanically robust to handle, flexible, stable in solvents and possess larger porosities than Triton-X100 cast buckypaper. They also exhibit a memory effect when bending wetted samples, returning to their former geometry on drying. Buckypaper and buckydiscs were studied by mercury intrusion porosimetry to reveal a defined distribution of mesopores and small macropores that is, along with their density and apparent free volume, dependant on the casting solvent and therefore tuneable. Moreover, the frit compression system also allows control over the 3-dimensional geometry of the buckydiscs during the casting process. 相似文献