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551.
Ammar R Baringer P Bean A Besson D Coppage D Copty N Davis R Hancock N Kelly M Kotov S Kravchenko I Kwak N Lam H Kubota Y Lattery M Momayezi M Nelson JK Patton S Poling R Savinov V Schrenk S Wang R Alam MS Kim IJ Ling Z Mahmood AH O'Neill JJ Severini H Sun CR Wappler F Crawford G Daubenmier CM Fulton R Fujino D Gan KK Honscheid K Kagan H Kass R Lee J Sung M White C Wolf A Zoeller MM Butler F Fu X Nemati B Ross WR Skubic P Wood M Bishai M Fast J Gerndt E Hinson JW McIlwain RL Miao T Miller DH 《Physical review letters》1995,74(18):3534-3537
552.
Avery P Besson D Garren L Yelton J Kinoshita K Pipkin FM Procario M Wilson R Wolinski J Xiao D Zhu Y Ammar R Baringer P Coppage D Haas P Kwak N Lam H Ro S Kubota Y Nelson JK Perticone D Poling R Fulton R Jensen T Johnson DR Kagan H Kass R Morrow F Whitmore J Wilson P Bortoletto D Dominick J McIlwain RL Miller DH Ng CR Schaffner SF Shibata EI Shipsey IP Yao W Sparks K Thorndike EH Wang C Alam MS Kim IJ Li WC Lou XC Romero V Sun CR Wang P Zoeller MM Goldberg M Haupt T Horwitz N Jain V Mestayer MD 《Physical review D: Particles and fields》1991,43(11):3599-3610
553.
Eun-Young Shin Chan-Soo Lee Mee-Hee Park Duk-Joong Kim Sahng-June Kwak Eung-Gook Kim 《Experimental & molecular medicine》2009,41(6):387-396
Angiotensin II (Ang II) stimulates migration of vascular smooth muscle cell (VSMC) in addition to its contribution to contraction and hypertrophy. It is well established that Rho GTPases regulate cellular contractility and migration by reorganizing the actin cytoskeleton. Ang II activates Rac1 GTPase, but its upstream guanine nucleotide exchange factor (GEF) remains elusive. Here, we show that Ang II-induced VSMC migration occurs in a βPIX GEF-dependent manner. βPIX-specific siRNA treatment significantly inhibited Ang II-induced VSMC migration. Ang II activated the catalytic activity of βPIX towards Rac1 in dose- and time-dependent manners. Activity reached a peak at 10 min and declined close to a basal level by 30 min following stimulation. Pharmacological inhibition with specific kinase inhibitors revealed the participation of protein kinase C, Src family kinase, and phosphatidylinositol 3-kinase (PI3-K) upstream of βPIX. Both p21-activated kinase and reactive oxygen species played key roles in cytoskeletal reorganization downstream of βPIX-Rac1. Taken together, our results suggest that βPIX is involved in Ang II-induced VSMC migration. 相似文献
554.
555.
Rong Quan FENG Jin Ho KWAK 《数学学报(英文版)》2007,23(1):23-28
Enumerating the isomorphism classes of several types of graph covering projections is one of the central research topics in enumerative topological graph theory. A covering of G is called circulant if its covering graph is circulant. Recently, the authors [Discrete Math., 277, 73-85 (2004)1 enumerated the isomorphism classes of circulant double coverings of a certain type, called a typical covering, and showed that no double covering of a circulant graph of valency three is circulant. Also, in [Graphs and Combinatorics, 21,386 400 (2005)], the isomorphism classes of circulant double coverings of a circulant graph of valency four are enumerated. In this paper, the isomorphism classes of circulant double coverings of a circulant graph of valency five are enumerated. 相似文献
556.
Minsuk Kwak Yong Hyun Shin U Jin Choi 《Journal of Mathematical Analysis and Applications》2009,355(2):527-540
We investigate an optimal portfolio, consumption and retirement decision problem in which an economic agent can determine the discretionary stopping time as a retirement time with constant labor wage and disutility. We allow the preference of the agent to be changed before and after retirement. It is assumed that the agent's coefficient of relative risk aversion becomes higher after retirement. Under a constant relative risk aversion (CRRA) utility function, we obtain the optimal policies in closed-forms using martingale methods and variational inequality methods. We give some numerical results of the optimal policies. We also consider the relation between the level of disutility and the labor wage with the optimal retirement wealth level. 相似文献
557.
558.
Seung‐Yeop Kwak Jun Hyung Kim Jong‐Chan Lee 《Journal of Polymer Science.Polymer Physics》2001,39(10):993-1000
This article establishes the processing–microstructure–motion–property relationship of high‐speed melt‐spun nylon‐6 fibers. From solid‐state 1H NMR T1ρ (spin–lattice relaxation time in the rotating frame) relaxation studies, all nylon‐6 fibers spun at 4500–6100 m/min showed three‐component exponential decay with the time constants T1ρ,I, T1ρ,II, and T1ρ,III, indicating that there existed three different motional phases. These phases were assigned to immobile crystalline, intermediate rigid amorphous, and mobile amorphous regions. The determination of the correlation time (τc) of the respective phases provided information about the local molecular mobility of each phase with respect to the spinning speed. As the spinning speed increased, τc of the crystalline region increased (4500–5200 m/min) and then reached a plateau. However, τc for the rigid amorphous region increased from 5200 m/min onward, indicating that the rigid amorphous chains were more oriented and constrained in the spinning speed range of 5500–6100 m/min. The drastic increase of the maximum thermal stress for all fibers from 5500 to 6100 m/min was coincident with the τc characteristics of the rigid amorphous region. The significant increase in tenacity and Young's modulus and the large decrease in elongation at break at 5500–6100 m/min were also in good agreement with the local molecular motion of the intermediate rigid amorphous phase in the nylon‐6 fibers. © 2001 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 39: 993–1000, 2001 相似文献
559.
In-Sook Lee Young-Woo Kwak Dong-Ha Kim Yong Cho Joji Ohshita 《Journal of organometallic chemistry》2008,693(20):3233-3239
A series of 2,6-bis(ethenylsilyl)-4,4-diphenyldithienosilole derivatives containing silylene-spacer were prepared by platinum-catalyzed hydrosilylation reaction. All the hydrosilylation proceeded regio- and stereoselectively to give solely β-(E)-adducts. The 2,6-bis(ethenylsilyl)-4,4-diphenyldithienosilole derivatives exhibit intense fluorescence emission and high quantum yields. The shoulder band of 9 in the emission spectrum was explained the intramolecular charge transfer from the electron-donating group (dimethylaminostyryl group) to electron-accepting group (dithienosilole moiety). These optical data are in good agreement with the results of theoretical calculations of model compounds at the level of B3LYP/6-31G(d,p). 相似文献
560.
Do Young Kwak Mikhail P. Levin 《Numerical Methods for Partial Differential Equations》2001,17(3):262-276
In this article, we consider a new technique that allows us to overcome the well‐known restriction of Godunov's theorem. According to Godunov's theorem, a second‐order explicit monotone scheme does not exist. The techniques in the construction of high‐resolution schemes with monotone properties near the discontinuities of the solution lie in choosing of one of two high‐resolution numerical solutions computed on different stencils. The criterion for choosing the final solution is proposed. Results of numerical tests that compare with the exact solution and with the numerical solution obtained by the first‐order monotone scheme are presented. © 2001 John Wiley & Sons, Inc. Numer Methods Partial Differential Eq 17: 262–276, 2001 相似文献