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81.
The influence of structure on the saturation behaviour of mode gain and the axial mode stability is investigated for different types of AlGaAs injection lasers. Both experimental and theoretical results confirm that carrier confinement along the lateral direction is effective for axial mode stabilisation. 相似文献
82.
Mito I. Kitamura M. Kaede K. Odagiri Y. Seki M. Sugimoto M. Kobayashi K. 《Electronics letters》1982,18(1):2-3
Using a new LPE growth technique, an InGaAsP/InP planar buried heterostructure laser diode (PBH-LD) has been realised in 1.3 and 1.5 ?m wavelength regions. As a result of the effective carrier confinement, CW threshold currents as low as 8.5 mA and 13 mA have been obtained in 1.3 and 1.5 ?m PHB-LDs, respectively, at room temperature. 相似文献
83.
Using a DFB-LD with two longitudinal modes in the 1.55 ?m region, the mode stability was examined experimentally. It is found that these modes are very stable under direct modulation at least up to around 300 Mbit/s and there is no power penalty due to mode partition noise in 97 km single-mode-fibre transmission at 280 Mbit/s. 相似文献
84.
Two-step purely thermal ion-exchange technique using two monovalent ions for single-mode waveguides is proposed. Experiments show embedded waveguide structure below the surface of the glass, as computer simulation predicted. The insertion loss of the straight waveguide was less than 1 dB for 19 mm long samples, at both λ=1.3 μm and 1.55 μm 相似文献
85.
We reported a case of long survival brain metastasis and meningeal carcinomatosis from lung cancer without radiochemotherapy. A 59-year-old female admitted to our hospital suffered from headache, anorexia and nausea. Papilledema was noticed, and examinations showed a brain tumor in the left parietal lobe and cancer cells in cerebrospinal fluid. Removal of the tumor and ventriculoperitoneal shunt were performed. Pathology showed adenocarcinoma. No neurological deficit was found during the postoperative course and the patient asked for home treatment. She survived for 25 months and spent a useful life in the 15 months after the onset in spite of no radiochemotherapy for meningeal carcinomatosis. In this case, because of the slow progression of the clinical symptoms, it is considered that cancer cells in the cerebrospinal fluid space grow slowly. The first CT and MRI findings of metastatic tumor of this case showed atypical for brain metastasis. Calcifications were found in plain CT and a high intensive tumor in both T1 and T2 weighted images of MRI. Enhancement due to contrast media was very slight in both CT and MRI. We considered that these findings were related to the slow growing of cancer cells. 相似文献
86.
Y Nirasawa T Mori Y Ito H Tanaka N Seki Y Atomi 《Canadian Metallurgical Quarterly》1998,33(4):663-665
Immunoglobulin M seroconversion to Ehrlichia chaffeensis was documented in U.S. citizens bitten by ticks in Sardinia. Seven cases of suspected ehrlichiosis in local residents were not confirmed by laboratory tests. In Alpine areas antibodies to E. phagocytophila were detected in persons at high risk, i.e., foresters (8.6%) and hunters (5.5%), and in controls (1.5%). Of 153 persons bitten by ticks, only one was Ehrlichia antibody-positive after 6 months. 相似文献
87.
AH Sarker S Ikeda H Nakano H Terato H Ide K Imai K Akiyama K Tsutsui Z Bo K Kubo K Yamamoto A Yasui MC Yoshida S Seki 《Canadian Metallurgical Quarterly》1998,282(4):761-774
The association patterns between maternal anthropometric characteristics (stature, prepregnancy weight, prepregnancy body mass index, pregnancy weight gain) and newborn size (birth weight, length, head circumference) were tested with 10,240 single births taking place between 1985 and 1995 in Vienna, Austria, and 3,452 single births taking place between 1989 and 1995 in Westerstede-Ammerland (Friesland), northern Germany. Maternal size and newborn size differed highly significantly (p < 0.001) between the two genetically and socioeconomically different population groups. Furthermore, the incidence of macrosomia among newborns (birth weight greater than 4000 g) was extraordinarily high (17.9%) in the Frisian group from northern Germany. In both populations taller and heavier women with a higher weight gain during pregnancy gave birth to heavier offspring. Nevertheless, the pregnancy weight gain, which indicates environmental conditions of the mother, had only a minor impact on newborn size compared with stature and prepregnancy weight, which reflect the maternal genetic potential to a higher degree. 相似文献
88.
M Tamura M Seki M Tsubota M Endo Y Tsunezuka H Sato 《Canadian Metallurgical Quarterly》1998,46(5):455-460
We report on the unprecedented combination of two recessively inherited disorders, the kyphoscoliosis type of Ehlers-Danlos syndrome (EDS type VI) and cystic fibrosis (CF), in two sibs born to consanguineous Turkish parents. Because of failure to thrive and bronchitis CF was diagnosed in the index patient early whereas EDS VI was recognized only very late. Both patients had marked muscular hypotonia at birth, delayed gross motor development, progressive kyphoscoliosis, joint dislocations, Marfanoid habitus, hypertrophic and atrophic scars, and osteopenia. EDS VI was proven by collagen studies and the pathognomonic pattern of urinary pyridinolines. Because the genes coding for the two disorders are located on different chromosomes and a chromosomal rearrangement was excluded, we conclude that their combination is a chance association. The cardiopulmonary impairment common to both diseases makes the prognosis dismal. 相似文献
89.
Rahmat Budiarto Masashi Yamada Hidenori Itoh Hirohisa Seki 《Computers & Industrial Engineering》1996,31(3-4):939-943
In many method of the cat's cradle string diagram processing in use today, there is no a strong emphasis on user interaction. This paper discusses a method for constructing cat's cradle string diagram in 2-D. The method uses a string representation and processing in 2-D which preserves the topology characteristics of the string diagram and also uses a small data volume. The inputted string diagram is transformed onto its cat's cradle string diagram by geometric transformation and GA. The method allows the user to interactively construct a cat's cradle string diagram. Three operations are used for constructing cat's cradle diagram, they are pull (over and under), release and exchange. An implemented program executed some shapes of cat's cradle for verifying the method. 相似文献
90.
BACKGROUND: To study the role of bezafibrate in prevention of restenosis after successful percutaneous transluminal coronary angioplasty (PTCA), we evaluated the incidence of restenosis and its correlation with serum lipid levels and effects on the coagulation-fibrinolytic system. METHODS: Subjects who had undergone successful elective PTCA were classified into three groups based on their triglyceride level and whether or not bezafibrate was administered. Fifty-two patients who had a triglyceride level < 150 mg/dl were classified as group A. Those with a triglyceride level +/- 150 mg/dl were randomly and prospectively allocated to receive either bezafibrate (group B, n = 21), or no lipid-lowering treatment (group C, n = 22). The restenosis rates in all three groups were subsequently monitored and correlated with serum levels of lipids and coagulation-fibrinolytic system markers. RESULTS: In the bezafibrate group, three of 21 patients (14%) had restenosis compared with 12 of 22 (55%) in group C and 18 of 52 (35%) in group A. In groups A and C, fibrinogen and triglyceride levels were significantly higher in the patients with restenosis. At the time of re-evaluation, serum triglyceride, fibrinogen, and plasminogen activator inhibitor type 1 (PAI-1) levels were lower and high-density lipoprotein (HDL) cholesterol levels were higher in the bezafibrate group than in group C. By logistic regression analysis, triglyceride and PAI-1 were found to be significant risk factors for postangioplasty restenosis. CONCLUSIONS: Triglyceride is a risk factor for post-PTCA restenosis, and bezafibrate reduces the post-PTCA restenosis rate in patients with a high triglyceride level. In the bezafibrate group, a significant decrease in PAI-1 was observed in association with a decrease in triglyceride level and an elevation of HDL cholesterol level. This suggests that improvement in fibrinolytic capacity is involved in the mechanism of decrease in the rate of restenosis. 相似文献