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441.
In recent years,bank credit business is booming with the increasing borrowing intention of China’s listed companies,and debt financing has become the major approach among listed companies’financing strategies.As a series of institutional arrangements about rights,responsibilities and benefits between different shareholders,corporate governance mechanism has a significant influence on the cost of debt financing.This paper employs variable coefficient panel data model to investigate the relationship of the listed company’s debt financing costs and corporate governance mechanism in terms of structural characteristics and time series characteristics.The results show that optimizing the structure of both Board of Directors and Board of Supervisors,establishing a reasonable management incentive system and reducing the concentration of ownership properly can directly contribute to a lower company’s debt financing costs.Meanwhile,property rights have an interactive influence on corporate governance from four aspects,which indirectly effect in company’s debt financing costs. 相似文献
442.
Takayuki Fujita Masanari Umemura Utako Yokoyama Satoshi Okumura Yoshihiro Ishikawa 《Cellular and molecular life sciences : CMLS》2017,74(4):591-606
As one of the most important second messengers, 3′,5′-cyclic adenosine monophosphate (cAMP) mediates various extracellular signals including hormones and neurotransmitters, and induces appropriate responses in diverse types of cells. Since cAMP was formerly believed to transmit signals through only two direct target molecules, protein kinase A and the cyclic nucleotide-gated channel, the sensational discovery in 1998 of another novel direct effecter of cAMP [exchange proteins directly activated by cAMP (Epac)] attracted a great deal of scientific interest in cAMP signaling. Numerous studies on Epac have since disclosed its important functions in various tissues in the body. Recently, observations of genetically manipulated mice in various pathogenic models have begun to reveal the in vivo significance of previous in vitro or cellular-level findings. Here, we focused on the function of Epac in the heart. Accumulating evidence has revealed that both Epac1 and Epac2 play important roles in the structure and function of the heart under physiological and pathological conditions. Accordingly, developing the ability to regulate cAMP-mediated signaling through Epac may lead to remarkable new therapies for the treatment of cardiac diseases. 相似文献
443.
444.
Isothermal fatigue (IF) tests were performed on H13 tool steel subjected to three different mechanical strain amplitudes at a constant temperature to determine the effects of mechanical strain amplitude on the microstructure of the steel samples. The samples' extent of damage after IF tests was compared by observation of their cracks and calculation of their damage parameters. Optical microscopy (OM) and scanning electron microscopy (SEM) were used to observe the microstructure of the samples. Cracks were observed to initiate at the surface because the strains and stresses there were the largest during thermal cycling. Mechanical strain accelerated the damage and softening of the steel. A larger mechanical strain caused greater deformation of the steel, which made the precipitated carbides easier to gather and grow along the deformation direction, possibly resulting in softening of the material or the initiation of cracks. 相似文献
445.
<正> This paper applies bilinear immersed finite elements (IFEs) in the interior penalty discontinuousGalerkin (DG) methods for solving a second order elliptic equation with discontinuous coefficient.A discontinuous bilinear IFE space is constructed and applied to both the symmetric and nonsymmetricinterior penalty DG formulations.The new methods can solve an interface problem on a Cartesianmesh independent of the interface with local refinement at any locations needed even if the interfacehas a nontrivial geometry.Numerical examples are provided to show features of these methods. 相似文献
446.
The paper is concerned with positive observer design for positive Markovian jump systems with partly known transition rates. By applying a linear co-positive type Lyapunov-Krasovskii function, a sufficient condition is proposed to ensure the stochastic stability of the error positive system and the existence of the positive observer, which is computed in linear programming. Finally, an example is given to demonstrate the validity of the main results. 相似文献
447.
448.
In this paper,we report the tribological properties of self-assembled molecular(SAM) films of fluoroalkylsilanes and non-fluoroalkylsilanes,with different chain-lengths,adsorbed on Si substrate surfaces by covalent bonds.The SAM films were characterized using a universal ball-disk experimental tester in aqueous solutions.The substrate surface was examined by X-ray photoelectron spectroscopy(XPS),and the SAM films adsorbed on the Si surfaces were inspected by contact angle measurements and XPS.Lubrication studies revealed that several kinds of fluoroalkylsilanes had similar friction coefficients;the small differences were attributed to the chain flexibility.In contrast,differences in the aqueous lubrication properties of SAM films of non-fluoroalkylsilanes were clearly identified.It is suggested that substitution with fluorine atoms and the surface affinities of fluoroalkylsilanes contributed to redistribution of surface changes,causing variations in lubrication behaviors. 相似文献
449.
This paper obtains some stability results for parametric generalized set-valued weak vector equilibrium problem. Under new assumptions, which do not contain any information about solution mappings, the authors establish the continuity of the solution mapping to a parametric generalized set-valued weak vector equilibrium problem without monotonicity. These results extend and improve some results in the literature. Some examples are given to illustrate the results. 相似文献
450.