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991.
Yoong-Ahm Kim Takuya Hayashi Satoru Naokawa Takashi Yanagisawa Morinobu Endo 《Carbon》2005,43(14):3005-3008
992.
Fumitaka Toudo Satoru Yanabu Satoaki Arai Yoshinori Masui 《Electrical Engineering in Japan》2005,152(4):42-49
The purpose of this investigation is to study the interruption performance of the Molded Case Circuit Breaker (MCCB) currently used for the protection of low‐voltage circuits. It is anticipated that interruptions, especially numerous high‐current interruptions, will degrade interruption performance. In order to investigate the performance change after many interruptions, it is important to understand the interruption characteristics. Multiple‐interruption experiments at large currents were conducted and the phenomena which govern the success or failure of interruption were identified. It was shown that after multiple interruptions a post‐arc current begins to flow and that the duration of the arc is ten to a few hundred microseconds. In order to explore the relationship between the post‐arc current and the degradation of the interruption characteristics, the conditions governing the post‐arc current were investigated experimentally. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 152(4): 42–49, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10358 相似文献
993.
S Jacquot T Kobata S Iwata C Morimoto SF Schlossman 《Canadian Metallurgical Quarterly》1997,159(6):2652-2657
CD40, a TNF receptor family member, plays a central role in T cell-mediated B cell activation. We have recently demonstrated that CD27, another TNF receptor family member, was also involved in B cell regulation and enhanced Ig production. In this report we compare CD27 and CD40 signals in B cell function. We selectively mimicked the effect of T cell help by addition to peripheral blood B cells activated with Staphylococcus aureus Cowan I strain and IL-2 of irradiated 300-19 cells transfected with either the CD70 (CD27 ligand) gene or the CD154 (CD40 ligand) gene, the vector alone, or both CD70 and CD154 genes. CD27 ligation induced only a slight increase in B cell proliferation compared with the dramatic enhancement induced by CD40 ligation; double ligation proved to be less efficient than CD40 ligation alone. In contrast, IgG production was increased only by CD27 ligation alone. Moreover, the CD27 signal was more efficient when it was given on day 2 of the culture rather than on day 0. Phenotypic analysis of the activated cells showed that CD27 ligation increased the percentage of cells showing a plasma cell profile (CD19-, CD38+), whereas upon CD40 ligation most of the cells still had a germinal center-like phenotype (CD19+, CD38+). Our results suggest that the CD27 and CD40 signals are not synergistic but, rather, are complementary and involve distinct steps of T cell-dependent B cell activation. CD27 may be more important in the induction of plasma cell differentiation at a time when the expansion phase has already occurred. 相似文献
994.
K Kondo T Kobayashi T Urakami T Kasugai M Iwata Y Sugino Y Suzuki N Shibata M Usui 《Canadian Metallurgical Quarterly》1997,35(8):900-904
We encountered three cases of thymic hyperplasia associated with hyperthyroidism. Case 1 was in a 35-year-old woman; a chest CT scan showed an anterior mediastinal mass and right-sided pleural effusion, which suggested the presence of a thymoma Case 2 was in a 21-year-old man who complained of palpebral ptosis and also had myasthenia gravis (Osserman type I). Case 3 was in a 47-year-old woman; a chest CT scan showed thymic hyperplasia and mediastinal lymphadenopathy. In all cases, anti-thyroid medication was given first, because of the associations with hyperthyroidism. Moreover, in cases 1 and 2 no tumor was found, and only hyperplasia was detected in the thymus, although both patients underwent extended thymectomy. Furthermore, surgery was not effective against the hyperthyroidism (anti-thyroid medication could not be withdrawn or reduced). In cases 2 and 3, thymic hyperplasia, as seen on chest CT scans, resolved as thyroid function was normalized by anti-thyroid medication. The pretracheal lymphadenopathy seen in case 3 also resolved. Thymic hyperplasia may have been a result, not a cause, of hyperthyroidism. When we encounter patients with thymic masses and hyperthyroidism, we should give anti-thyroid medication and observe the thymus for some time before resorting to surgery. 相似文献
995.
Yosuke Iwata Hiroyoshi Naito Masaru Inoue Melanie Klasen-Memmer 《Thin solid films》2008,517(4):1421-1423
A method for measuring the complete set of the Leslie viscosity coefficients of nematic liquid crystals (NLCs) with negative dielectric anisotropy (Δε < 0) is proposed. The method is based on the analysis of the transient current, induced by step voltage excitation, in homeotropic NLC cells. It has been shown that the transient current in homeotropic NLC cells with Δε < 0 can be explained by the theory of NLCs in which the flow effects and the free-slip boundary condition are taken into account [Y. Iwata et al., Jpn. J. Appl. Phys. 43 (2004) L 1588]. It is demonstrated that the complete set of the Leslie viscosity coefficients of NLCs with Δε < 0 can be simultaneously and accurately measured by fitting the transient current calculated by the theory to the experimental data with a differential correction method. 相似文献
996.
M Nomoto SI Iwata S Kaseda T Fukuda S Nakagawa 《Canadian Metallurgical Quarterly》1997,767(2):235-238
Nocardia species are ubiquitous in the environment and may be found in the soil. They are generally responsible for sporadic pulmonary diseases acquired by inhalation of spores, with secondary localizations in the central nervous system and subcutaneous tissues. There is no absolute evidence for person to person transmission. Presumptive outbreaks of nocardiosis were observed in immunocompromised patients, more frequently in kidney transplant patients than in cardiac transplant patients. Nocardia spp., being present in dust particles, closure and disinfection of the transplantation unit with formaldehyde arrested the sequence of cases of nocardiosis. The original sources of the Nocardia sp. remain doubtful. Other possible sources of contamination are other patients, medical staff and the hospital environment. The first studies of Nocardia spp. typing were based on the detection of extracellular antigens, on the susceptibility of actinomycete strains to killer yeasts, and on the biochemical profiles with fluorogenic substrate. The use of molecular typing techniques have given very promising results. Analysis of plasmid profiles is an interesting way to compare the identity of isolates, although the reliability of this method depends of the presence of plasmids in the isolates. Other typing methods, including analysis of restriction length fragment polymorphism of total DNA, ribosomal DNA fingerprinting, require further investigations to evaluate their discriminating power or to be easily interpretable, whereas a random amplified polymorphic DNA (RAPD) assay was successful for epidemiological purposes. Progress in epidemiological analysis of cases of nocardiosis will be consistent when an improved diagnosis of this infection (molecular and serological diagnosis) will be available, when the genetic diversity of Nocardia spp. isolates will be better known, and when molecular typing, that hold promise in complementing investigations of outbreak of these infections, will be systematically performed when an abnormal increase of cases of nocardiosis in a population with risk factors is observed. 相似文献
997.
MJ Shirley BA Iwata SW Kahng JL Mazaleski DC Lerman 《Canadian Metallurgical Quarterly》1997,30(1):93-104
We examined the effectiveness of functional communication training (FCT) in reducing self-injurious behavior (SIB) and in shaping an alternative (communicative) response while SIB continued to be reinforced. Following a functional analysis of 3 individuals' SIB, we attempted to teach an alternative response consisting of a manual sign to each individual, using the reinforcer that maintained SIB. When FCT was implemented without extinction. SIB remained at baseline rates for all participants, and none of the participants acquired the alternative response. When extinction was added to the training procedure, SIB decreased and manual signing increased for all participants. To determine if signing, when established, would compete with SIB when both were reinforced, extinction was then withdrawn. Signing was maintained and SIB occurred at low rates for 2 individuals, but SIB returned to baseline rates for the 3rd individual, necessitating the reimplementation of extinction. These results suggest that it may be difficult to establish alternative behaviors if inappropriate behavior continues to be reinforced, but that, when established, alternative behavior might compete successfully with ongoing contingencies of reinforcement for inappropriate behavior. 相似文献
998.
Temperature and time dependences of the ferroelastic domain structure were observed near the ferroelastic phase transition temperature in [N(CH3)4]2ZnBr4 single crystal. It was, found that the domain structure reaches a metastable state within about 20sec after quenching. The domain size increases with decreasing temperature. 相似文献
999.
1000.
T Komori N Shibata M Kobayashi S Sasaki M Iwata 《Canadian Metallurgical Quarterly》1998,95(4):338-344
The published literature indicates 11% of CIN I lesions on average progress to a higher grade dysplasia and the remainder either regress or persist. Reliable markers of disease outcome are yet to be identified. A longitudinal study of 342 women referred for colposcopic examination of a CIN I detected by a screening Pap test, and classified by the colposcopic impression and Pap test at that exam as = CIN 1 was designed to identify predictors of disease outcome. The cohort was comprised of 220 women who satisfactorily completed the study and whose disease was neither biopsied or treated at the initial examination. All had HPV DNA testing by PCR, and were followed with interval colposcopic examinations and repeat Pap tests for a limited time period. The initial HPV DNA status and a number of measured clinico-pathological and risk factor variables were analyzed to identify outcome predictors. All underwent a biopsy either at the conclusion of the study or because their disease was considered to have progressed during the follow up period. Biopsy confirmed progression to CIN II/III occurred in 41 (18.6%), persistence of CIN I/Condyloma in 41 (18.6%), and regression to 相似文献