控股股东股权质押、投资效率与公司期权价值

本文以2003—2017年中国A股上市公司为研究样本,分析了控股股东股权质押对上市公司投资效率及公司期权价值的影响。研究发现,控股股东股权质押不利于公司更好地把握投资机会,抑制了公司投资支出—投资机会敏感性;控股股东股权质押不仅加剧了企业过度投资,尤其是面临较差投资机会企业的过度投资,也恶化了企业投资不足,尤其是面临较好投资机会企业的投资不足;对于投资机会较好的公司,控股股东股权质押对公司增长期权价值影响不显著,而对于投资机会较差的公司,控股股东股权质押对公司清算期权价值的影响显著负相关。进一步研究发现,融资约束和市场化环境对控股股东股权质押与投资支出—投资机会敏感性之间关系具有异质性的调节作用

70年来中国财务会计研究的演进与发展

纵观70年来中国财务会计研究的发展历程,由于特殊的历史背景和独特的社会经济发展模式,中国的财务会计研究呈现出不同于西方的发展特点。它经历了从引进苏联模式的财务会计理论框架到转向借鉴具有国际视野的财务会计研究体系,于摸索中前进,在改革中创新,不断寻求符合企业实践需要和经济发展要求的财务会计理论体系与研究范式。尽管面临诸多挑战,发展之路曲折,但在学者们的共同努力与辛勤探索下,中国的财务会计研究进程不断向前推进。一方面,得益于资本市场的发展和数据可用性的增强,研究方法更加多样化,为解释商业活动提供了更有说服力的证据;另一方面,财务会计研究广泛地吸收了其他学科的理论特色,多学科互动频繁,研究课题趋于多元化。当前,互联网、云计算、区块链等信息技术革新火热进行,理念、技术开拓创新,驱动着财务会计研究的持续创新;宏观经济政策面临调整升级,财税、金融等体制亟待革新,国企改革步伐不断加快,为财务会计研究提供了新的思路;产业结构与生产力更新变革,资本市场、公司治理在实践中不断催生新的范式。这些都将为财务会计研究提供新的素材,使得财务会计的研究话题更加新颖,研究视野不断拓宽,进而促进具有中国特色、把握时代潮流和顺应国际趋势的财务会计研究体系不断完善。国家自然科学基金项目“多边代理视角下创业企业的激励机制及管理权转移研究”(71572167

控股股东股权质押与企业投资行为——基于金融投资和实业投资的视角

本文以2007—2017年我国沪深两市非金融上市公司的半年度数据为研究对象,从金融投资和实业投资的视角,考察了控股股东股权质押对上市公司投资行为的影响。实证研究发现,控股股东股权质押比例与上市公司的金融投资水平呈U形关系,与上市公司的实业投资水平呈倒U形关系。这说明不同质押比例下控股股东出于不同的动机做出的改变和调整上市公司的投资决策,对金融投资和实业投资产生非线性影响。以上结论在尽可能控制内生性问题以及一系列稳健性检验后依然成立。进一步研究发现:产权性质、控制权转移风险以及金融资产与经营资产收益率差对控股股东股权质押比例与上市公司投资行为之间的关系具有重要的调节作用。本研究揭示了控股股东股权质押在公司投资策略方面的经济后果,低质押比例的控股股东更有可能支持上市公司,而高质押比例的控股股东更可能损害上市公司提供了增量证据

农村留守经历大学生成人依恋及影响因素分析

目的探讨农村留守经历大学生(URLB)成人依恋现状及其影响因素。方法采用亲密关系体验问卷及自编问卷对河北省2所高校1062名有农村留守经历的大学生进行自填式问卷调查。结果成人依恋回避和依恋焦虑维度平均得分分别为(4.16±0.53),(3.82±0.82)分;多元线性回归分析表明,性别(β=0.236)及与父母联系频次(β=0.073)为URLB依恋回避的影响因素;性别(β=0.079)、留守家庭生活满意度(β=-0.074)、开始留守时间(β=-0.12)及与抚养人沟通情况(β=0.066)为URLB依恋焦虑的影响因素。结论性别以及童年期的留守经历对URLB成人依恋的发展有影响

新型磷杂菲酯类衍生物的合成及热稳定性研究

磷杂菲衍生物是一类重要的阻燃材料.由磷杂菲与甲醛反应得到的中间体分别与各种酰氯反应得到一系列新型的磷杂菲酯类衍生物,利用1H NMR、13C NMR、31P NMR、FT-IR、HR-MS和ESI-MS对化合物的结构做了表征.讨论了催化剂用量、物料比、溶剂、反应物浓度、反应时间及温度对反应的影响,并对反应进行优化.对代表化合物的热稳定性做了测试,结果表明这类磷杂菲酯类衍生物具有良好的热稳定性,可以作为阻燃材料使用

Significance of Mangrove Pollen in Research of Marine Geology

红树林是热带—亚热带海岸潮间带的一种特有的植被类型和指示植物 .根据沉积物中出现的红树植物花粉种类和数量 ,推测了海滨红树林的演化、海面升降、海岸线变迁 ,追溯了古海流和沉积物来源 ,阐述了红树植物花粉在海洋地质研究中对深入探讨古环境变化和海陆相互作用等方面的重要意义 .Mangrove flora are special vegetation and indicative plants existing in certain areas of tropical and subtropical coasts.According to the variety and quantity of mangrove pollen discoveried in the sediments,this paper inferred the evolution of mangrove flora and changes of sea level and paleo-shoreline.Mangrove pollen also provide evidence for tracing paleo-ocean current and sediments source.In marine geological research,the study on mangrove pollen is also important for exploring paleoenvironment changes and ocean-continent interaction.国家自然科学基金资助项目 ( 4 95 76 2 87) ;; 华东师范大学河口海岸国家重点实验室资助项目 ( 2 0 0 0 0 1) ;; 国家海洋局海底科学 重点实验室资助项目 ( 2 0 0 1-4

脱氧胆酸改性普鲁兰多糖纳米粒子制备与表征

通过酯化反应将脱氧胆酸偶联于普鲁兰多糖骨架形成具有两亲性的普鲁兰多糖衍生物(DP),采用纳米沉淀法制备纳米粒子(DPNs),考察制备条件对纳米粒子性质影响,为进一步将其作为药物载体的研究提供基础。衍生物DP结构通过FT-IR和1 H NMR表征,DPNs经透射电镜、动态光散射仪和zeta电位仪表征检测。获得不同取代度脱氧胆酸改性普鲁兰多糖衍生物,制备得到的纳米粒子呈球形,表面光滑规整,平均粒径100～300nm,zeta电位在-20mV左右。脱氧胆酸改性普鲁兰多糖衍生物通过纳米沉淀法能制备出纳米粒子,颗粒性质受制备条件影响

Mechanism of geniposide in improving free fatty acid metabolism in rats with non-alcoholic fatty liver disease

观察栀子苷改善非酒精性脂肪性肝病的效果,从游离脂肪酸探讨栀子苷调节非酒精性脂肪性肝病的作用机制。健康雄性Wistar大鼠40只,随机分为4组:正常组、模型组、栀子苷组和血脂康组,每组大鼠10只,正常组大鼠给予正常大鼠饲料喂养,其余3组大鼠均采用高脂饲料喂养以诱导非酒精性脂肪性肝病,造模时间为8周,从第5周起至第8周末,栀子苷组和血脂康组分别灌服相应的药物。记录大鼠体重、肝湿重、脂肪质量;用相应方法检测肝组织TG,FFA,FAS,AMPK,ACCase及Malonyl-Co A含量,血清CHO,LDL-C的含量,血清AST,ALT的活性;观察肝脏组织肉眼及病理变化(HE染色法)。结果显示,与正常组相比,模型组大鼠的体重;肝湿重;脂肪重;血清CHO,LDL-C,ALT,AST;肝组织TG,FFA,FAS,ACCase及Malonyl-Co A含量皆显著升高(P<0.01);肝组织AMPK活性显著降低(P<0.01),肝组织肉眼外观及病理切片脂肪变性明显,并出现炎症损伤;与模型组相比,栀子苷组大鼠体重、脂肪质量、肝组织FFA含量、血清ALT,AST活性均显著降低(P<0.01),肝湿重,肝组织TG,FAS,ACCase及Malonyl-Co A含量明显降低(P<0.05),肝组织AMPK活性明显增多(P<0.05),肝脏肉眼外观及病理学表现均有所改善;与模型组相比,血脂康组大鼠的肝湿重、脂肪质量、肝组织TG,FFA和血清LDL-C水平明显降低(P<0.05);与血脂康组相比,栀子苷组大鼠的体重、脂肪质量、肝组织FFA含量均显著降低(P<0.01),其他方面无明显差异。结果表明,栀子苷具有显著的改善高脂饮食诱导的大鼠非酒精性脂肪性肝病的药理效应;其改善大鼠非酒精性脂肪性肝病的游离脂肪酸代谢是通过调节"AMPK-ACCase-Malonyl-Co A-FFA"轴来实现的。To observe the effect of geniposide on non-alcoholic fatty liver disease( NAFLD),and discuss the mechanism of geniposide for NAFLD from the aspect of free fatty acid,forty healthy Wistar male rats were randomly divided into normal group,model group,geniposide and Xuezhikang group. The rats in normal group were fed with normal diets,and the rats in other 3 groups were given with high-fat diet for 8 weeks to induce the NAFLD models. From the week 5 to end of week 8,the rats in geniposide and Xuezhikang group were intervened with corresponding medicines. The body weight,liver wet weight,and fat weight of the rats were recorded.Visual and pathological changes in hepatic tissues were observed with HE staining. The contents of TG,FFA,FAS,AMPK,ACCase and Malonyl-Co A in hepatic tissue,contents of CHO and LDL-C in serum and activities of AST and ALT in serum were detected by using corresponding methods. The results showed that the body weight,liver wet weight,and fat weight of the rats,CHO,LDL-C,ALT and AST levels in serum,TG,FFA,FAS,ACCase and Malonyl-Co A levels in hepatic tissues of the rats in model group were significantly higher than those in normal group( P < 0. 01),while AMPK activity was significantly lower than that of the normal group( P < 0. 01),with obvious visual and pathological steatosis in hepatic tissues,and inflammatory injury occurred in model group. Compared with the model group,body weight of the rat,fat weight,levels of FFA in hepatic tissues,ALT and AST activities in serum,liver wet weight,TG,FAS,ACCase and Malonyl-Co A levels were significantly decreased in geniposide group( P < 0. 01),while the AMPK activity in hepatic tissues was significantly increased( P < 0. 05),with improvement in visual and pathological performance.Compared with the model group,liver wet weight,fat weight,TG and FFA levels in hepatic tissues,and LDL-C level in serum were significantly decreased in Xuezhikang group( P < 0. 05). Compared with Xuezhikang group,the body weight of rat,fat weight and FFA level in hepatic tissues were significantly lower in geniposide group( P < 0. 01),but with no significant difference in other aspects. These findings indicated that geniposide was highly effective in improving the pharmacological effect of NAFLD induced by highfat diet,and the mechanism was achieved through AMPK-ACCase-Malonyl-Co A-FFA axis.国家自然科学基金项目(81274155;81503529);; 福建省自然科学基金项目(2014J01374);; 福建省高等学校新世纪人才计划项目;; 厦门市科技计划项目(3502Z20134020);; 福建省中医药科研项目(WZPW201308

First Sagittarius A* Event Horizon Telescope Results. VIII. Physical Interpretation of the Polarized Ring

In a companion paper, we present the first spatially resolved polarized image of Sagittarius A* on event horizon scales, captured using the Event Horizon Telescope, a global very long baseline interferometric array operating at a wavelength of 1.3 mm. Here we interpret this image using both simple analytic models and numerical general relativistic magnetohydrodynamic (GRMHD) simulations. The large spatially resolved linear polarization fraction (24%–28%, peaking at ∼40%) is the most stringent constraint on parameter space, disfavoring models that are too Faraday depolarized. Similar to our studies of M87*, polarimetric constraints reinforce a preference for GRMHD models with dynamically important magnetic fields. Although the spiral morphology of the polarization pattern is known to constrain the spin and inclination angle, the time-variable rotation measure (RM) of Sgr A* (equivalent to ≈46° ± 12° rotation at 228 GHz) limits its present utility as a constraint. If we attribute the RM to internal Faraday rotation, then the motion of accreting material is inferred to be counterclockwise, contrary to inferences based on historical polarized flares, and no model satisfies all polarimetric and total intensity constraints. On the other hand, if we attribute the mean RM to an external Faraday screen, then the motion of accreting material is inferred to be clockwise, and one model passes all applied total intensity and polarimetric constraints: a model with strong magnetic fields, a spin parameter of 0.94, and an inclination of 150°. We discuss how future 345 GHz and dynamical imaging will mitigate our present uncertainties and provide additional constraints on the black hole and its accretion flow