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51.
The Film Dryout Analysis Code in Subchannels, FIDAS, has been developed with the main objective of predicting dryout and post-dryout heat transfer in a channel and in rod bundles. In FIDAS, two-phase flow consisting of continuous liquid film, continuous vapor and entrained droplets is modeled by a three-fluid, three-field representation of 12 field equations, i.e. three continuity, three energy and six momentum equations. FIDAS can predict dryout without any empirical CHF correlations by introducing annular flow modeling and the ‘film dryout criterion’. Experiments on film flow characteristics, subchannel flow and enthalpy distributions, dryout and post-dryout heat transfer in tubes and rod bundles were analyzed to demonstrate the performance of FIDAS. The predictions of FIDAS are in close agreement with the experiments. 相似文献
52.
Previous studies have demonstrated an infiltration of monocytes and increased levels of granulocyte-macrophage colony-stimulating factor (GM-CSF) in the asthmatic lung. To study the possible effects of this cytokine upon the differentiation and function of these newly recruited monocytes, we have developed a model in which monocytes isolated from human peripheral blood were differentiated into macrophages in serum in the presence or absence of GM-CSF. After 7 days, the macrophages increased in size and granularity, had increased phagocytic activity, and expressed various adhesion molecules, CD14 and major histocompatibility complex (MHC) class II. The effects of GM-CSF on antigen presentation by cultured macrophages on the antigen-specific proliferative response of CD4+ T cells to Dermatophagoides pteronyssinus or purified protein derivative of tuberculin and the mitogen phytohaemagglutinin was determined. CD4+ T-cell proliferation was reduced when either antigen was presented by macrophages cultured in serum alone, compared with the values obtained with freshly isolated monocytes. However, CD4+ cell proliferation was comparable to that observed with monocytes when antigen was presented by macrophages which had been pre-cultured with 50 U/ml GM-CSF. CD4+ T-cell proliferation to phytohaemagglutinin was similar when all three populations were used as accessory cells. High numbers of macrophages partially suppressed CD4+ T-cell proliferation in response to antigen presented by monocytes, but there was no significant difference between macrophages cultured in the presence or absence of GM-CSF. This data suggests that GM-CSF directs monocyte differentiation into macrophages with an antigen-presenting, rather than a suppressive, phenotype. Elevated levels of GM-CSF in the asthmatic lung may therefore maintain recently recruited monocytes in an inflammatory and T-cell activating state. 相似文献
53.
Sasaki K. Tomaru T. Ajima Y. Ogitsu T. Araoka O. Higashi N. Iida M. Kasami K. Kimura N. Makida Y. Nakamoto T. Ohhata H. Okamura T. Sugawara S. Tanaka K. Yamamoto A. 《Applied Superconductivity, IEEE Transactions on》2008,18(2):142-145
Magnetic field measurements have been performed for the first full-scale magnet system assembled with the cryostat for the J-PARC proton beam line of neutrino experiment. In the measurement system, the probe position with respect to magnet central axis is measured by a Helium Neon laser and a position sensitive detector, PSD, in order to obtain an exact dipole field strength. Errors associated with the PSD misalignment and influences on the PSD signals by the magnetic field were evaluated. The measured dipole components approached to the design values by compensating those with the probe position. The latest beam simulation indicated that the measured values of magnetic field were good enough for the primary proton beam transport. 相似文献
54.
55.
H Sato K Suzuki S Nakaji K Sugawara M Totsuka K Sato 《Canadian Metallurgical Quarterly》1998,53(2):431-440
The suboptimal efficacy of the currently available 23-valent pneumococcal vaccine in the growing population of adults >65 years old may be related to the limited immunogenicity of the vaccine polysaccharides in this group. In this study, the majority of elderly outpatients with stable chronic illnesses generated a vigorous IgG response to seven vaccine serotypes comparable to that of healthy young adults at 1, 3, and 16 months after immunization. Moreover, the quality and function of anticapsular antibodies, measured as avidity and in vitro opsonization, were comparable between elderly and young subjects over time. However, a subset (approximately 20%) of elderly outpatients responded to fewer than two of seven serotypes tested 1 and 3 months after immunization, whereas none of the healthy young adults were such poor responders. Thus, despite the adequate mean immune responses of the elderly as a group, a substantial proportion of elderly persons may have poor responses to the currently available pneumococcal vaccine. 相似文献
56.
Ishida M. Hatori N. Otsubo K. Yamamoto T. Nakata Y. Ebe H. Sugawara M. Arakawa Y. 《Electronics letters》2007,43(4):219-221
Low-driving-current temperature-stable 10 Gbit/s direct modulation was achieved for optimised 200 mum-long short cavity 1.3 mum p-doped quantum dot lasers. Driving conditions were 25.2 mAp-p for the modulation current and 23.4 mA for the bias current through the whole temperature range from 20 to 90degC 相似文献
57.
K. Sugawara L. Faramarzi N. Nakamura 《International Journal of Rock Mechanics and Mining Sciences》2006,43(2):179-191
A new scheme named the Traveling Load Test is proposed to measure the macroscopic deformation modulus of the floor rock mass in an open pit, covering a volume of rock mass much larger than conventional loading tests. Facility of the test includes extra-large excavators as load-sources on the flat surface and high-resolution borehole tilt-meters installed in rock to detect the microscopic tilt induced by the load. Emphasis is given to the theory of deformation modulus determination, which is applicable to the field where the floor is fully covered by an accumulation of loose blocks of stone produced by blasting damage and/or stress relief. The relation between the induced tilt and the traveling load is formulated, and subsequently it is shown how the deformation modulus is determined by analyzing the induced tilt-loading distance curve, within acceptable engineering accuracy. 相似文献
58.
59.
A human RNA helicase gene, DBP1, was cloned by PCR methodsusing degenerate oligonucleotide primers corresponding to highly conserved motifs among known members of the DEAH-box protein family. The full-length DBP1 contains 3028 nucleotides and codes for a protein of 813 amino acids with a calculated mol. wt. of 92723 daltons. The predicted amino acid sequence shares extensive homology with Prp2, Prp16, and Prp22 proteins, which are required to splice mRNA precursors in budding yeast. The protein encoded by DBP1 has RGD, RD, and HS(A/T) repeat motifs close to the N-terminus. Southern blot analysis suggested the presence of a homologue of the DBP1 genes in other species, and Northern blot analysis showed that DBP1 is expressed ubiquitously in various human organs investigated. The DBP1 gene was found to be on chromosome 4p15.3 and encodes a putative nuclear ATP-dependent RNA helicase. 相似文献
60.
J Hayashi K Yamamoto M Sugawara Y Fujita S Nakazawa F Oguma S Tsuchida H Miyamura S Eguchi 《Canadian Metallurgical Quarterly》1992,40(10):1866-1870
Between January 1980 and August 1991, 99 patients underwent operation for mitral valve regurgitation (MR). The ages of the patients ranged from 12 to 67 years, (49.4 +/- 11.9 years), and there were 39 males and 60 females. Pathological cause of regurgitation, which was determined by intraoperative inspection and histological findings of excised leaflets, was rheumatic in 46, degenerative in 38, infective endocarditis in 9, ischemic in 4 and unknown in 2 patients. Cardiac rhythm was atrial fibrillation in 73, normal sinus rhythm in 24 and junctional rhythm in 2 patients. Our principles for valve repair were (1) excision of responsible segment and repair for prolapsed leaflet due to torn chordae, (2) shortening of elongated chordae, (3) annuloplasty, and (4) repair of perforated leaflet. Finally, 19 patients endured plastic operation, and 80 patients underwent prosthetic valve replacement. The rate of plastic procedure was 62.5% (10/16) in degenerative MR with mural chordal lesions, 42.9% (3/7) in rheumatic MR without stenosis, 22.2% (2/9) in infective endocarditis and 100% (2/2) in MR with unknown etiology. Mitral valve repair was failed both in rheumatic MR associated with stenosis (39 patients) and in ischemic MR (4 patients). A ten-year survival rate after operation was 92.2 +/- 3.1% in patients with valve replacement and 83.6 +/- 10.0% with valve repair (N.S.), and a proportion of event-free survival in patients with valve replacement was similar to valve. Late postoperative cardiac catheterization revealed decreased left ventricular volume indices and increased left ventricular end-systolic stress/volume ratio in both groups compared to preoperative values, respectively.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献