经济周期波动、财务柔性选择与企业业绩

利用经济周期性波动作为自然实验研究财务柔性选择引起的企业业绩变化,从而为财务柔性与企业成长关系提供微观证据.基于财务柔性与企业成长关系中"资本筹集"的理论观点——财务柔性选择能够及时获取财务资源、降低企业的融资约束程度、带来企业业绩的提升,文章提供了这一作用机制的实证证据.研究发现在经济紧缩时期财务柔性选择可以显著提升企业业绩,进一步考察发现这一作用机制在非预算软约束企业中表现更明显;而经济扩张时期财务柔性选择一定程度上会造成企业价值的毁损,弱化了经济周期的优化效应.研究丰富了财务柔性与企业成长关系的理论,对企业制定和运用财务柔性策略具有重要的实践指导意义.     

地方性本科院校与重点大学财务管理专业本科课程之比较

文章通过对我国地方性本科院校与重点大学财务管理专业本科课程的比较,在公共基础课程、专业基础课程、专业课、实践课程环节这四方面进行了初步分析,对地方性本科院校财务管理专业建构科学的课程体系有若干启示。     

Epigallocatechin-3-gallate affects the growth of LNCaP cells via membrane fluidity and distribution of cellular zinc

Objective: To evaluate effects of epigallocatechin-3-gallate (EGCG) on the viability, membrane properties, and zinc distribution, with and without the presence of Zn2+, in human prostate carcinoma LNCaP cells. Methods: We examined changes in cellular morphology and membrane fluidity of LNCaP cells, distribution of cellular zinc, and the incorporated portion of EGCG after treatments with EGCG, Zn2+, and EGCG+Zn2+. Results: We observed an alteration in cellular morphology and a decrease in membrane fluidity of LNCaP cells after treatment with EGCG or Zn2+. The proportion of EGCG incorporated into liposomes treated with the mixture of EGCG and Zn2+ at the ratio of 1:l was 90.57%, which was significantly higher than that treated with EGCG alone (30.33%). Electron spin resonance (ESR) studies and determination of fatty acids showed that the effects of EGCG on the membrane fluidity of LNCaP were decreased by Zn2+. EGCG accelerated the accumulation of zinc in the mitochondria and cytosol as observed by atomic absorption spectrometer. Conclusion: These results show that EGCG interacted with cell membrane,decreased the membrane fluidity of LNCaP cells, and accelerated zinc accumulation in the mitochondria and cytosol, which could be the mechanism by which EGCG inhibits proliferation of LNCaP cells. In addition, high concentrations of Zn2+ could attenuate the actions elicited by EGCG.     

Optimal design of Stewart platforms based on expanding the control bandwidth while considering the hydraulic system design

We proposed an optimal design method to expand the bandwidth for the control of large hydraulic Stewart platform. The method is based on generalized natural frequency and takes hydraulic oil into consideration. A Lagrangian formulation which considers the whole leg inertia is presented to obtain the accurate equivalent mass matrix. Using the model, the effect of leg inertia and the influence of design parameters on the generalized natural frequency are investigated. Finally, numerical examples are presented to validate and confirm the efficiency of the mathematical model. The results show that the leg inertia, especially the piston part plays an important role in the dynamics. The optimum diameter ratio of the base to the moving platform is between 2 and 3, and the optimum joint angle ratio of the base to the moving platform is about 1. The smaller joint angles and a longer leg stroke are favorable for raising system frequencies. The system oil should be preprocessed for large platforms with a requirement for good dynamic performance.     

基于BIM技术和递进式思想的“施工组织”课程设计全过程设计

依据"递进式"课程设计模式将BIM技术应用于"施工组织"课程设计的全过程,进行了全新的设计,包括任务的设计、具体内容的设计及考核评价的设计,为实践教学的改革提供借鉴。     

教师培训教学原则初探

教师培训是提高教师整体素质的重要途径，教师培训的教学原则是指导教师培训的一般原则，它包括以前沿性知识为培训内容的原则，以受训教师的经验为基础的原则，以解决问题为中心的原则等。     

基于混合式教学及雨课堂在大学计算机基础中的应用与思考

在《大学计算机基础》课程中应用混合式教学模式,被许多高校引用过,但是教学效果却不尽如人意。本研究总结以往混合式教学失利的原因,发挥混合式教学的优势,结合PBL的教学方法,利用雨课堂平台实现互动式教学,形成新的教学方法。研究以某校371名学生的期末成绩进行分析,研究表明:新式的混合式教学应用到《大学计算机基础》实践课中是可行的。     

CALL教学中应当怎样注意网络交流中的礼仪问题

外语教学中非常注重学生跨文化交流能力的培养,计算机用于教学中以后,广大教师和学生经常地使用到电子邮件、键友、电子论坛、电子聊天、网络视频会议等等资源。因此,网络跨文化交流能力变得尤为重要。作为一名外语教师,特别是担负基础外语教学任务的外语教师,了解一定的网络交流礼仪是十分必要的。     

Optimization of conditions for supercritical fluid extraction of flavonoids from hops (Humulus lupulus L.)

Waste hops are good sources of flavonoids. Extraction of flavonoids from waste hops (SC-CO₂ extracted hops) using supercritical fluids technology was investigated. Various temperatures, pressures and concentrations of ethanol (modifier) and the ratio (w/w) of solvent to material were tested in this study. The results of single factor and orthogonal experiments showed that at 50°C, 25 MPa, the ratio of solvent to material (50%), ethanol concentration (80%) resulted in maximum extraction yield flavonoids (7.8 mg/g). HPLC-MS analysis of the extracts indicated that flavonoids obtained were xanthohumol, the principal prenylflavonoid in hops. Project (No. Y304203) supported by the Natural Science Foundation of Zhejiang Province, China     

Effects of fructose-1,6-diphosphate on concentration of calcium and activities of sarcoplosnic Ca^2＋-ATPase in cardiomyocytes of Adriamycin-treated rats

Objective: To observe the effects of fructose-1,6-diphosphate (FDP) on serum levels of cardiac troponin 1 (cTnl) and creatine kinase-MB (CK-MB), as well as the concentration of calcium in cardiomyocytes (Myo[Ca2 ]) and activity of sarcoplosnic Ca2 -ATPase (SRCa2 -ATPase) in Adriamycin (ADR)-treated rats. Methods: Rats were intraperitoneally injected with ADR (2.5 mg/kg every other day for 6 times) and then with different dosages of FDP (every other day for twenty-one times). Bi-antibodies sandwich Enzyme linked immune absorption assay (ELISA) was performed to detect serum level of cTnl. CK-MB was detected by monoclonal antibody, Myo[Ca2 ] was detected by fluorescent spectrophotometry and the activity of SRCa2 -ATPase was detected by inorganic phosphate method. Results: FDP (300, 600, 1200 mg/kg) significantly reduced the serum levels of cTnl and CK-MB, while at the same time decreased calcium concentration and increased SRCa2 -ATPase activity in cardiomyocytes of ADR-treated rats (P<0.01). Conclusions: FDP might alleviate the cardiotoxic effects induced by ADR through decreasing calcium level as well as increasing SRCa2 -ATPase activity in cardiomyocytes.