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1.
An elastic half plane with an oblique edge crack is considered in this paper. A pair of concentrated forces or point dislocations is assumed to act at an arbitrary point in the half plane. The half plane with an edge crack is first mapped into a unit circle by a rational mapping function so that the following analysis can be carried out on the mapped plane analytically. Then the complex stress functions are derived by separating the whole problem into two parts; one is the principal part corresponding to the infinite plane acted on by concentrated forces or dislocations, the other is the holomorphic part, which can be determined by making use of the property of regularity of complex stress functions. The stress intensity factors of the crack can be calculated with different inclined angles of the crack, and the displacement and stress components at an arbitrary position in the half plane can be expressed explicitly. 相似文献
2.
Masaaki Miyamoto Hiroyuki Koike Toshio Sada Yasuteru Ijima Junichiro Fukushige Norio Nakamura 《Lipids》1991,26(12):1316-1319
Platelet-activating factor (PAF) is a potent inflammatory mediator which is released by various inflammatory cells and produced
by certain tissues, including the kidney. PAF has been shown to increase glomerular permeability to protein and to decrease
glomerular filtration rate (GFR) by contracting mesangium. On the basis of these observations, it has been suspected that
PAF may play a role as mediator of glomerular damage in glomerular nephritis. To examine this possibility, we studied the
effects of a specific PAF antagonist, R-75,317, on the development of an experimental model of anti-glomerular basement membrane
(anti-GBM) glomerulonephritis. Glomerulonephritis was initiated by injecting rabbit anti-rat GBM serum into rats. Proteinuria
gradually developed after serum injection, plateaued at week 2, and remained at the high level of week 2 throughout the experimental
period (6 wk). Chronic treatment with R-75,317 (10 mg/kg/day i.p.) tended to delay the onset of proteinuria and significantly
accelerated the recovery phase. Creatinine clearance (Ccr) fell to 40% at week 3. R-75,317 treatment completely prevented
this decline of Ccr. Histological changes in this model (glomerular hypertrophy, proliferation of mesangial matrix and interstitial
fibrosis) were also ameliorated by the R-75,317 treatment. The results suggest that PAF may play a role in the development
of glomerulonephritis and that PAF antagonists could be used in the treatment of human renal disease.
Based on a paper presented at the Third International Conference on Platelet-Activating Factor and Structurally Related Alkyl
Ether Lipids, May 1989. 相似文献
3.
Norio Tsubokawa 《Polymer Bulletin》1989,22(1):55-62
Summary The ring-opening polymerization of 2-oxazolines (OXZs) was found to be initiated by chloromethyl groups introduced onto carbon black surface. The introduction of chloromethyl groups onto the surface was achieved by the reaction of carbon black with 3,3-bischloromethylbenzoyl peroxide in carbon tetrachloride. During the polymerization, poly-OXZs were grafted from carbon black based on the propagation of the polymers from the surface: percentage of grafting increased with an increase of conversion and reached 40–60%. The polymerization was accelerated by the addition of potassium iodide. Poly-OXZ-grafted carbon black produced stable colloidal dispersions in both hydrophobic and hydrophilic solvents. 相似文献
4.
Takashi Noji Yoji Koike Hideo Iwasaki Masatsune Kato Norio Kobayashi Yoshitami Saito 《Journal of Superconductivity and Novel Magnetism》1996,9(1):65-71
Anisotropie properties of the single crystal Pb2Sr2Ho0.5Ca0.5Cu3O8 have been investigated by measuring the electrical resistivity in theab-planeρ ab (H, θ,T), which depends on the angleθ between theab-plane and the magnetic-field direction, in various constant fieldsH perpendicular to the current direction. All the angle-dependent values ofρ ab (H, θ,T) at a constant temperature are scaled to be on one curve as a function of reduced field. The anisotropic parameter γ≡(m c * /m ab * )1/2 is estimated as 12–13, which is larger than that of YBa2Cu3O7 and much smaller than that of Bi2Sr2CaCu2O8. It has been concluded that the anisotropy does not always depend on the thickness of the blocking layer but seems to depend on the overlap of the electronic wave functions along thec-axis. Anisotropy in the pinning potential has also been discussed from the resistive tail in the temperature dependence ofρ ab (H,θ,T). 相似文献
5.
Reiji Hattori Shuhei Yamada Yoshitomo Masuda Norio Nihei 《Journal of the Society for Information Display》2004,12(1):75-80
Abstract— We have developed new powder materials that exhibit liquid behavior, which can lead to the realization of novel bistable and reflective displays having paper‐white appearance, high contrast, and quick response. Two types of display were demonstrated, one had 160 × 160 array of pixels and the other had 320 × 320 in a 3.1‐in.‐diagonal viewable image size corresponding to 66 and 132 dpi, respectively. These displays were driven by passive‐matrix addressing. The displays showed a reflectivity of more than 41%, a contrast more than 1:10, and a pixel response time of less than 0.2 msec. The seven‐segment display for use in clocks was also demonstrated. 相似文献
6.
This paper describes the effect of ultra-thin liquid lubricant films on air bearing dynamics and flyability of less than 10 nm spacing flying head sliders in hard disk drives. In particular, the effect of non-uniform lubricant film distributions on head/disk interface dynamics are studied. The disks with lubricant on one half of disk surface thicker than the other half were used in this study. The dynamics of sliders is monitored using acoustic emission (AE) and the interactions between the slider and disk are investigated experimentally. The disks were also examined with a scanning micro-ellipsometer before and after each test. Complicated slider responses were observed and clarified. In addition, it was found that the periodic lubricant film thickness modulations or non-uniformity caused by the slider-disk contact interactions could be observed. It is suggested that this lubricant film thickness non-uniformity will be one of the technical issues in order to achieve ultra-low head/disk contact interface of less than 10 nm. 相似文献
7.
Takuo Suganuma SungDoke Lee Tetsuo Kinoshita Norio Shiratori 《New Generation Computing》2001,19(2):173-191
In this paper, we propose an agent architecture to improve flexibility of a videoconference system with strategy-centric adaptive
QoS (Quality of Service) control mechanism. The proposed architecture realizes more flexibility by changing their QoS control
strategies dynamically. To switch the strategies, system considers the properties of problems occurred on QoS and status of
problem solving process. This architecture is introduced as a part of knowledge base of agent that deals with cooperation
between software module of videoconference systems. We have implemented the mechanism, and our prototype system shows its
capability of flexible problem solving against the QoS degradation, along with other possible problems within the given time
limitation. Thus we confirmed that the proposed architecture can improve its flexibility of a videoconference system compared
to traditional systems.
Takuo Suganuma, Dr.Eng.: He is a research associate of Research Institute of Electrical Communication of Tohoku University. He received a Dr.Eng.
degree from Chiba Institute of Technology in 1997. His research interests include agent-based computing and design methodology
for distributed systems. He is a member of IPSJ, IEICE and IEEE.
SungDoke Lee: He is a Ph.D. Student in the Graduate School of Information Sciences in Tohoku University. He received his MEng degree at
Chonbuk National University, Korea in 1991. His research interests include Flexible Network and Knowledge of Agent.
Tetsuo Kinoshita, Dr.Eng.: He is an associate professor of Research Institute of Electrical Communication of Tohoku University. He received a Dr.Eng.
degree in information engineering from Tohoku University, Japan. His research interests include knowledge engineering, cooperative
distributed processing and agent-based computing. He received the the IPSJ Best Paper Award in 1997, etc. He is a member of
IPSJ, IEICE, JSAI, AAAI, ACM and IEEE.
Norio Shiratori, Dr.Eng.: After receiving his Dr.Eng degree at Tohoku University, he joined the Research Institute of Electrical Communication of
Tohoku University in 1977, and is now a professor at the same University. He has been engaged in research on distributed processing
system, and flexible intelligent network. He received the 25th Anniversary of IPSJ Memorial Prize-Winning Paper Award in 1985,
the 6th Telecommunications Advancement Foundation Incorporation Award in 1991, the Best Paper Award of ICOIN-9 in 1994, the
IPSJ Best Paper Award in 1997, etc. He has been named a Fellow of the IEEE for his contributions to the field of computer
communication networks. 相似文献
8.
The ion-selective property of hydrous ferric oxide precipitate films has been investigated by measuring membrane potentials which arise across precipitate membranes of hydrous ferric oxide with and without adsorbed MoO42? ions and of ferric molybdate in solutions of NaCl, KCl, MgCl2, CaCl2, BaCl2, AlCl3, and FeCl3. The hydrous ferric oxide membrane was only permeable to Cl? ions in chloride solutions, whereas the membrane with adsorbed MoO42? ions was permeable to cations in NaCl and KCl solutions, and to both Cl? and cations in the presence of multivalent cations. The ferric molybdate membrane was permeable to Cl? and cations in NaCl and KCl solutions, and only to Cl? ions in the presence of multivalent cations. It is suggested that in chloride solutions, the corrosion of iron covered with a precipitate film of hydrous ferric oxide is accelerated by enrichment of Cl? ions under the film, which may decrease the local pH and introduce a positive diffusion potential in the film. The adsorption of MoO42? ions on the oxide changes the ion-selectivity of the precipitate film from the anion-selective to the cation-selective in solutions of NaCl and KCl. This cation-selectivity of the film may inhibit the corrosion of iron, because of H+ ions diffusing out of the film. The inhibitive effect of MoO42? ions would be reduced in the presence of multivalent cations. 相似文献
9.
Masaharu Takeda Hiroyuki Hiraishi Toshikazu Takesako Sumio Tanase Norio Gunge 《Yeast (Chichester, England)》1996,12(3):241-246
The 36K protein attached at the 5′ end of the linear DNA plasmid pGKL2 from the yeast Kluyveromyces lactis was first purified and characterized. The terminal protein was purified from cells (1 kg wet weight) by ammonium sulphate precipitation and two rounds of centrifugation to equilibrium in CsCl gradients. The pGKL2 was present only in the post-microsomal supernatant. Approximately 10 mg of the purified pGKL2 was recovered and digested with DNase I. The terminal protein (final ca. 0·8 mg) was homogeneous by electrophoresis and we determined the N-terminal amino acid sequence up to ten residues, showing that it existed in the cryptic N-terminal domain of pGKL2-ORF2 (DNA polymerase) sequence. 相似文献
10.
Shinji Miwa Norio Yamamoto Katsuhiro Hayashi Akihiko Takeuchi Kentaro Igarashi Hiroyuki Tsuchiya 《International journal of molecular sciences》2022,23(3)
Simple SummaryChondrosarcomas develop chemoresistance to standard anticancer drugs, making it difficult to control unresectable or metastatic chondrosarcomas. To improve the clinical outcomes of chondrosarcoma, new treatment approaches, such as molecule-targeting agents and immunotherapy, are needed. Recent research has revealed promising biomarkers and therapeutic targets for chondrosarcoma. In addition, several molecule-targeting agents have shown favorable antitumor activities in several clinical studies in patients with advanced sarcomas, including chondrosarcoma. This review summarizes recent basic studies on biomarkers and therapeutic targets and recent clinical studies on treating chondrosarcomas.AbstractDue to resistance to standard anticancer agents, it is difficult to control the disease progression in patients with metastatic or unresectable chondrosarcoma. Novel therapeutic approaches, such as molecule-targeting drugs and immunotherapy, are required to improve clinical outcomes in patients with advanced chondrosarcoma. Recent studies have suggested several promising biomarkers and therapeutic targets for chondrosarcoma, including IDH1/2 and COL2A1. Several molecule-targeting agents and immunotherapies have shown favorable antitumor activity in clinical studies in patients with advanced chondrosarcomas. This review summarizes recent basic studies on biomarkers and molecular targets and recent clinical studies on the treatment of chondrosarcomas. 相似文献