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821.
In this paper, first we introduce the full expression for the Ricci tensor of a real hypersurface M in complex two-plane Grassmannians G2(Cm+2) from the equation of Gauss. Next we prove that a Hopf hypersurface in complex two-plane Grassmannians G2(Cm+2) with commuting Ricci tensor is locally congruent to a tube of radius r over a totally geodesic G2(Cm+1). Finally it can be verified that there do not exist any Hopf Einstein hypersurfaces in G2(Cm+2). 相似文献
822.
Guo Nan Yin Do-Kyun Kim Ji In Kang Yebin Im Dong Sun Lee Ah-reum Han Jiyeon Ock Min-Ji Choi Mi-Hye Kwon Anita Limanjaya Saet-Byel Jung Jimin Yang Kwang Wook Min Jeongwon Yun Yongjun Koh Jong-Eun Park Daehee Hwang Jun-Kyu Suh Ji-Kan Ryu Ho Min Kim 《Experimental & molecular medicine》2022,54(5):626
Diabetes mellitus (DM) is a chronic metabolic disorder characterized by inappropriate hyperglycemia, which causes endothelial dysfunction and peripheral neuropathy, ultimately leading to multiple complications. One prevalent complication is diabetic erectile dysfunction (ED), which is more severe and more resistant to treatment than nondiabetic ED. The serum glycoprotein leucine-rich ɑ-2-glycoprotein 1 (LRG1) is a modulator of TGF-β-mediated angiogenesis and has been proposed as a biomarker for a variety of diseases, including DM. Here, we found that the adhesion GPCR latrophilin-2 (LPHN2) is a TGF-β-independent receptor of LRG1. By interacting with LPHN2, LRG1 promotes both angiogenic and neurotrophic processes in mouse tissue explants under hyperglycemic conditions. Preclinical studies in a diabetic ED mouse model showed that LRG1 administration into the penile tissue, which exhibits significantly increased LPHN2 expression, fully restores erectile function by rescuing vascular and neurological abnormalities. Further investigations revealed that PI3K, AKT, and NF-κB p65 constitute the key intracellular signaling pathway of the LRG1/LPHN2 axis, providing important mechanistic insights into LRG1-mediated angiogenesis and nerve regeneration in DM. Our findings suggest that LRG1 can be a potential new therapeutic option for treating aberrant peripheral blood vessels and neuropathy associated with diabetic complications, such as diabetic ED.Subject terms: Biological therapy, Cytokines, Recombinant protein therapy, Extracellular signalling molecules 相似文献
823.
H.Y. Byun I.J. Chung Y.-S. Suh H.K. Shim D.Y. Kim C.Y. Kim 《Macromolecular Symposia》2003,192(1):151-160
A blend of a newly synthesized polyfluorene(PDHBF) and polyvinylcarbazole(PVK) exhibits a photoluminescence(PL) emission spectrum of PDHBF without an increase in the PL intensity on photoexcitation at 340 nm, the UV-visible absorption maximum of PVK, despite of a substantial spectrum overlap. However, the indirect photoexcitation of the blend suppresses the secondary emission of the PL with the maximum at 520 nm. The chromophores generating the secondary emission are formed when the chromophores are photoexcited above the critical energy level of an excited state. The chromophores formed by the energy transfer have energy lower than the critical energy and fail to form the excimers. A low temperature PL study of the blend in a cryogenic chamber proves that the energy transfer in the system takes place mainly between the excimers of PVK generated by the partially eclipsed dimeric states of two carbazole units and the fluorophores of PDHBF. 相似文献
824.
Young Jin Suh 《Mathematische Nachrichten》2023,296(1):382-401
First we introduce a new notion of generalized Killing Ricci tensor which is equivalent to the notion of cyclic parallel Ricci tensor for real hypersurfaces in the complex quadric . Next, in terms of -principal or -isotropic unit normal vector fields we give a complete classification of real hypersurfaces in with cyclic parallel Ricci tensor. 相似文献
825.
Monodisperse micron‐sized polystyrene particles crosslinked with a novel poly(ethylene oxide)‐poly(propylene oxide)‐poly(ethylene oxide) triblock diol diacrylate (t‐BDDA) were produced via simple dispersion polymerization. It was established that the monomer‐diffusible surface characteristics of primary particles played a decisive role in producing the monodisperse crosslinked polymer particles. We named this concept a diffusion‐controlled polymerization method, DPM. Here in this study, particularly, t‐BDDA is proposed as a very useful crosslinker capable of self‐assembling and crosslinking in the process of particle formation and particle growth. 相似文献
826.
Nam P. Suh 《Macromolecular Symposia》2003,201(1):187-202
Microcellular plastics (MCP) refer to any plastic with tiny bubbles of less than about 50 microns. It is made by subjecting polymers with a large amount of dissolved gas to a thermodynamic instability so as to nucleate a large number of cells instantaneously. MCP has been extruded and injection molded to make various industrial products. The fundamental theory for design of MCP and the processing methods are reviewed. It also discusses the design of equipment, including the die or mold, for MCP processing. The performance of MCP and the advantages of using MCP are presented. Some of industrial applications are also highlighted. 相似文献
827.
Young Jin Suh 《Mathematische Nachrichten》2023,296(8):3630-3651
We introduce the notion of harmonic curvature for real hypersurfaces in the complex quadric . First, we prove that the unit normal vector field N on real hypersurfaces in with harmonic curvature is singular, that is, -principal or -isotropic. Next by using a new notion of cyclic semiparallel Ricci tensor, we give a new result on real hypersurfaces with harmonic curvature and constant mean curvature in . 相似文献