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21.
A new type of nonsalt solar pond was investigated by field testing. The roof of the solar pond was formed using a transparent double film. Three kinds of tests were carried out under the following conditions: (1) insulating pellets were packed between the layers of the transparent double film of the roof at sunset; (2) the water surface of the pond was insulated using only the two transparent films; (3) the water surface of the pond was covered by the double film with the top surface blackened on which solar energy can be collected, while pond water was circulated using a solar cell powered submerged water pump. The warm water stored in the solar pond by the above methods was utilized as a heat source for a gas engine powered heat pump used to heat a greenhouse. In this report, the results of the field tests on the above solar ponds and greenhouse heating system are discussed. Also the utility of a combination plant using a solar pond and underground borehole storage system is evaluated.Important conclusions on performance are as follows: (1) collection efficiencies of these solar ponds become 9–54% corresponding to the weather conditions and pond temperatures; (2) maximum temperature of the pond water under weather conditions at Osaka is about 80°C; (3) the solar pond can be effectively utilized for heating a greenhouse; (4) the combination plant using the solar pond and the underground storage layer can store heat of 1119 MJ m−2 yr−1. 相似文献
22.
To elucidate whether and why glucose directly influences renin secretion, the effect of glucose on renin secretion was investigated in the rat. In an in vivo study, renin activity significantly (p<0.01) increased from the basal value of 7.6 +/- 1.4 to 14.2 +/- 3.2 ng Ang I/ml/hr (mean +/- SD) after intravenous glucose (1.0 g/kg, in 50% glucose solution ) injection. Propranolol (10.5 mg/kg) pretreatment partly abolished the increase in renin activity induced by glucose injection. In an in vitro study, the isolated kidneys of male Wistar rats (200-250 g) were perfused with a basal perfusing medium containing 5.5 mM glucose for 20 min, and then perfused with the medium containing 16.5 mM glucose, 27.5 mM glucose, 5.5 mM glucose + 22 mM mannitol, 27.5 mM glucose + 1 microM phentolamine, or 27.5 mM glucose + 1 microM propranolol for 10 min, respectively. Renin activity was significantly increased from a basal value of 8.1 +/- 4.5 to peak value of 17.9 +/- 3.0 ng Ang I/ml/hr (p<0.01) by 16.5 mM glucose, to 59.0 +/- 10.5 ng Ang I/ml/hr (p<0.005) by 27.5 mM glucose, and to 24.7 +/- 5.8 ng Ang I/ml/hr (p<0.01) by 5.5 mM glucose + 22 mM mannitol. The increase in renin activity in the kidney perfused with 27.5 mM glucose was significantly (p<0.005) higher than that with 16.5 mM glucose or that with 5.5 mM glucose + 22 mM mannitol. The 27.5 mM glucose-stimulated increase in renin activity was not changed by the addition of 1 microM phentolamine, while it was completely abolished by the addition of 1 microM propranolol. These results suggest that glucose has a direct stimulating effect on renin secretion probably through beta-adrenergic mechanisms in the rat. 相似文献
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H Moriwaki N Kume T Sawamura T Aoyama H Hoshikawa H Ochi E Nishi T Masaki T Kita 《Canadian Metallurgical Quarterly》1998,18(10):1541-1547
Endothelial dysfunction, or activation, elicited by oxidized low density lipoprotein (Ox-LDL) and its lipid constituents has been shown to play a key role in the pathogenesis of atherosclerosis. We recently have identified a novel receptor for Ox-LDL-designated lectin-like Ox-LDL receptor (LOX-1) in vascular endothelial cells. To examine ligand specificity of LOX-1, we established CHO cell lines stably expressing both human and bovine LOX-1 (LOX-1-CHO). LOX-1-CHO bound and degraded 125I-labeled Ox-LDL but did not significantly degrade 125I-labeled acetylated LDL (Ac-LDL). Fucoidin and maleylated BSA (M-BSA), which inhibit 125I-Ox-LDL binding to class A scavenger receptors, did not inhibit 125I-Ox-LDL binding or degradation in LOX-1-CHO. Polyinosinic acid and carrageenan, in contrast, significantly reduced 125I-Ox-LDL binding to LOX-1-CHO by 62% and 60%, respectively. Delipidated and untreated 125I-Ox-LDL were bound and degraded equally in LOX-1-CHO; furthermore, excess amounts of unlabeled, delipidated Ox-LDL inhibited binding and degradation of untreated 125I-Ox-LDL. Taken together, LOX-1 is a receptor for Ox-LDL but not for Ac-LDL. LOX-1 recognizes protein moiety of Ox-LDL, and its ligand specificity is distinct from other receptors for Ox-LDL, including class A and B scavenger receptors. 相似文献
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Ohnishi T. Mukaiyama K. Yamanishi M. Ochi N. Ono Y. Kan Y. Ishikawa H. Suemune I. 《Photonics Technology Letters, IEEE》1990,2(8):546-548
A high-speed switching, as fast as 300 ps, of spontaneous emission is achieved in the recently developed quantum-confined field-effect light emitting triode. As a result of the combination of the field control of radiative life time with modulation of carrier-generation rate, the light intensity modulation does not rely on changes in carrier population at all but on the field control of the radiative life time in the quantum well structure of the device. Elaborated is the allowance for the deviation of the modulation depth of injection current from an optimum value in the modulation scheme 相似文献
27.
When tensile stress was applied to epoxy resin filled with silica particles, we expected that the stress concentration would occur in the epoxy matrix near the interface between the matrix and the silica particles. We investigated the plastic deformation of the network chains near the interface, which was quantitatively evaluated using a polarized microscope FTIR technique. A biphenol‐type epoxy resin, which has a mesogenic group in the backbone moiety, was used as the matrix resin. As a result, reorientation of the network chains along the direction of the tensile stress near the interface with the silica particles was observed. Especially when the silica/matrix interface has good bonding properties, the reorientation of the network chains was observed at a larger area around the silica particles. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 787–794, 2003 相似文献
28.
Shigeo Shimizu Yutaka Ochi Atsushi Nakano Matthew Bone 《Journal of the Society for Information Display》2005,13(1):3-8
Abstract— This paper presents a new display device, which combines a digital backplane and a vertically aligned nematic liquid‐crystal layer. The device has 1280 × 720 pixels in a 0.7‐in.‐diagonal display area. In this paper, we present the concept of the new device and overview the performance of the device for a rear‐projection television application. 相似文献
29.
M Ichimura M Okamoto S Mori H Tohge K Ochi H Harada 《Canadian Metallurgical Quarterly》1998,19(5):687-691
PURPOSE: Our goal was to assess the MR appearance and histologic correlation of primary pulmonary artery angiosarcoma. METHOD: Four patients with tumorous masses in the pulmonary arteries were evaluated by dynamic contrast-enhanced MRI using T1- and T2-weighted SE images, GE images, as well as coronal 3D MRA in breath-hold technique. The percentage of tumor enhancement was determined by measuring regions of interest before and after Gd-DTPA administration on the 2D multiplanar spoiled GRE images. RESULTS: All four masses showed some contrast enhancement on the dynamically acquired GRE images. The degree of contrast enhancement correlated with the degree of tumor differentiation, content of myxoid matrix, and associated thrombus. Contrast-enhanced 3D MRA was useful for preoperative delineation of the peripheral pulmonary arteries to the subsegmental order. CONCLUSION: Dynamic contrast-enhanced 3D MRA of the pulmonary arteries can be used to delineate pulmonary arterial angiosarcomas preoperatively. Considerable variability of contrast agent uptake reflects the wide histologic behavior of these masses in differentiation from central pulmonary embolism. 相似文献
30.
H Takeda T Matozaki Y Fujioka T Takada T Noguchi T Yamao M Tsuda F Ochi K Fukunaga S Narumiya T Yamamoto M Kasuga 《Canadian Metallurgical Quarterly》1998,16(23):3019-3027
SHPS-1 is an approximately 120 kDa glycosylated receptor like protein that contains three immunoglobulin-like domains in its extracellular region as well as four potential tyrosine phosphorylation and SRC homology 2 (SH2) domain binding sites in its cytoplasmic region. Lysophosphatidic acid (LPA) stimulated the rapid tyrosine phosphorylation of SHPS-1 and its subsequent association with SHP-2, a protein tyrosine phosphatase containing SH2 domains in Rat-1 fibroblasts. LAP-induced tyrosine phosphorylation of SHPS-1 was inhibited by Clostridium botulinum C3 exoenzyme (which inactivates RHO) but not by pertussis toxin. The protein kinase C activator phorbol ester, 12-O-tetradecanoylphorbol 13-acetate (TPA) also stimulated tyrosine phosphorylation of SHPS-1; however, down-regulation of protein kinase C by prolonged exposure of cells to TPA did not affect LAP-induced tyrosine phosphorylation of SHPS-1. LPA-induced tyrosine phosphorylation of SHPS-1 was markedly reduced in either focal adhesion kinase (FAK)-deficient mouse cells or CHO cells overexpressing the tyrosine kinase CSK. Overexpression of a catalytically inactivate SHP-2 markedly inhibited MAP kinase activation in response to low concentrations of LPA in CHO cells, whereas overexpression of a wild-type SHPS-1 did enhance this effect of LPA. Furthermore, MAP kinase activation in response to a low concentration of LPA was inhibited by botulinum C3 exoenzyme. These results indicate that LPA-induced tyrosine phosphorylation of SHPS-1 and its association with SHP-2 may be mediated by a RHO-dependent pathway that includes FAK and a SRC family kinase. Thus, in addition to its role in receptor tyrosine kinase-mediated MAP kinase activation, the formation of a complex between SHPS-1 and SHP-2 may, in part, play an important role in the activation of MAP kinase in response to low concentrations of LPA. 相似文献