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131.
In pregnant female rat, oxygen tension was measured in vivo with an oxygen microelectrode and the following statistically significant data (Student's test) were obtained: -- not significant variability in four groups of six control rats; -- highly significant decrease of oxygen tension twenty-four hours after biovariectomy in four groups of six operated rats; -- in twelve operated and treated by substitutive hormonotherapy rats, pO2 was at the same level than in control rats; -- in eighteen operated rats, the oxygen tension measured after embryonic death was identical to control rats. These experiments clearly demonstrate twenty four hours after biovariectomy a decreased oxygen tension. Simultaneously to this decrease, a diminution of uterine blood flow takes place. This pO2 diminution should be dependent on decrease of ovarian hormones since the substitutive hormonotherapy prevents its appearance. A good explanation of this phenomenon is the high requirement of hypoxic embryo for oxygen; moreover after the embryonic death, the intra-uterine pO2 increases. 相似文献
132.
133.
A variable-pressure scanning electron microscopy (VP-SEM) with a cooling stage permits long hours of observation of water-containing specimens in their natural or close to natural state, without the conventional specimen preparations of fixation, dehydration, drying and metal coating. It reduces water vaporization and beam damage by keeping the specimens at a low temperature. We observed Bacillus cereus colonies on nutrient agar, which would shrink significantly if any conventional specimen preparation technique were used. We also studied the growing process of the bacteria on raw and steamed rice using the VP-SEM without conventional preparation techniques. Original specimens were directly mounted onto specimen holders and their backscattered electron images observed under the following conditions: specimen stage temperature, -10 degrees C; specimen chamber vacuum level, 30-70 Pa; and accelerating voltage, 15-20 kV. We recognized that the VP-SEM minimized deformation of the colonies due to shrinkage of the nutrient agar, and successfully imaged the morphology of the colonies and bacteria without a decline in bacteria number, which is apt to occur during fixation and dehydration. Also, the growth process of the bacteria on raw or steamed rice could be observed promptly, since there is no specimen preparation step. 相似文献
134.
Electrically controlled fiber variable-optical-attenuator arrays with polymer-network liquid crystals are shown to be compact and to have a large attenuation range (30-40 dB) and low residual loss (0.55 dB) at wavelengths from 1.3 to 1.6 mum. Their estimated power consumption is very low (<30 nW/channel), and arrays with more than ten channels can be made. The manufacturing process is simple: Trenches 30-100 mum wide are cut across parallel conductive-layer-coated optical fibers and are filled with a polymer-network liquid crystal. The attenuation properties depend on UV-curing conditions and on trench width. 相似文献
135.
用低温光荧光(PL)和透射电子显微镜(TEM)研究了表面氮化自组织InAs/GaAs量子点的光学性能和微观结构。结果表明氮化后形成薄层的InAsN薄膜作为应变缓和层覆盖在量子点的表面,使得随着氮化时间的增加,InAs量子点的位错密度提高、尺寸变大、纵横比提高、发光波长变长、强度变低。 相似文献
136.
Ryo Toda Yuki Matsushita Mitsunori Hieda Taku Matsushita Nobuo Wada 《Journal of Low Temperature Physics》2007,148(5-6):785-790
We have measured the heat capacity of 3He adsorbed on three-dimensionally connected nanopores, 2.7 nm in diameter, preplated with about 1.3 atomic layers of 4He. At low coverages of 3He, the 3He heat capacity is roughly constant at the measured temperatures between 0.1 and 1 K. Its molar heat capacity is on the order
of the gas constant R, between 1.1R and 1.8R. This suggests a Boltzmann gas state of the adsorbed 3He. At high coverages, the heat capacity is likely approaching linear in T at low temperatures, which suggests a degenerate state at further lower temperatures. 相似文献
137.
Horinaka H. Matsunaka T. Nakamura N. Mukaiyama T. Kawakami S. Wada K. Hirano Y. Kojima C. Kono K. 《Electronics letters》2007,43(23)
Optical absorption images of the tissue mimic phantom including gold nanoparticles were obtained by detecting the ultrasonic velocity-change caused by light irradiation. A series of experimental results showed the possibility as a nanoparticle distribution monitor for the drug delivery system. 相似文献
138.
Wada Yuichi Takagi Yoichiro Mori Teijiro Hamano Suenobu Miyamoto Toshio Itoh Toshio 《Industry Applications, IEEE Transactions on》1980,(1):30-39
The increase in electric power consumption in industry has led to the development of modern distribution systems such as control centers having high kVA ratings and high prospective fault current. In such a situation, the improvement of the system usefulness such as reliability and cost effectiveness is the essential requirement. An index is presented to evaluate the system usefulness using the cost effectiveness for fault protection in a system of given bank kVA. The index is estimated on four different system structures of control centers, including one which utilizes Permanent Power Fuses (PPF). It is presented that the PPF combined with molded case circuit breaker in main circuit effectively improves the cost effectiveness in control centers with high fault current. Operating principles of the PPF and the control center utilizing the PPF are briefly outlined. 相似文献
139.
Takayuki Wada Author Vitae Author Vitae 《Automatica》2010,46(8):1339-1345
Efficient randomized algorithms are developed for solving robust feasibility problems with multiple parameter-dependent convex constraints. Two complementary strategies are presented, both of which exploit the multiplicity to achieve fast convergence. One is the stochastic ellipsoid method with multiple updates. In each iteration of this algorithm, an ellipsoid which describes a candidate of the solution set is updated many times via the multiple constraints with one random sample, while at most one update is allowed in the original method. The other is the stochastic ellipsoid method with multiple cuts. Here, a new update rule is presented to construct a smaller ellipsoid directly via multiple subgradients given by the constraints. A quantitative analysis of the volume of the ellipsoid is also provided, which guarantees the advantage of the proposed algorithm over the original one. The above features lead to a reduction of the total number of random samples necessary for convergence, which is extensively demonstrated through numerical examples. 相似文献
140.
A Mori S Tamura T Katsuno Y Nishimura T Itoh K Saheki H Takatsuka H Wada Y Fujimori T Okamoto Y Takemoto E Kakishita 《Canadian Metallurgical Quarterly》1999,6(1):55-58
STUDY OBJECTIVE: To evaluate the efficacy of conservative laparoscopic surgery in a series of patients with stage III-IV endometriosis. DESIGN: Prospective study (Canadian Task Force classification II-1). SETTING: University-affiliated hospital. PATIENTS: All 141 women who underwent conservative operative laparoscopy for stage III-IV endometriosis between January 1993 and December 1996 and were followed for a minimum of 6 months. INTERVENTIONS: Laparoscopic procedures performed with scissors, bipolar coagulation, and hydrodissection. MEASUREMENTS AND MAIN RESULTS: Clinical examination, transvaginal ultrasonography, and pain questionnaire were scheduled every 6 months postoperatively. The cumulative proportion of pregnant patients and cumulative recurrence rate were calculated by Kaplan-Meier method. Twenty-five women (44%) with infertility became pregnant. Twenty-three (51%) had stage III and two (16.7%, p <0.05) had stage IV endometriosis. The 24-month cumulative pregnancy rate was 57.5%. Thirty-one women (22%) reported pain recurrence during follow-up. Five (3.5%) recurrences were confirmed by histologic examination and eight (5.7%) were documented only by clinical and ultrasonographic findings. No recurrence occurred in the first 6 months of follow-up. CONCLUSION: Operative laparoscopy seems to be effective treatment for stage III endometriosis. A larger series with longer follow-up is necessary to clarify its role in the management of stage IV disease. (J Am Assoc Gynecol Laparosc 6(1):55-58, 1999) 相似文献