Persistence and Extinction of a Non-Autonomous Plant Disease Model with Roguing^*

On the basis of analyzing the shortages of present studies on plant disease model for autonomous phenomenon, and considering the actual situation, this paper applies the joint factors of environmental change and the infectivity for latent plants into the system;therefore we deal with a non-autonomous plant disease model with roguing. Some sufficient conditions are established for extinction of diseases and permanence of the system in this paper.

Numerical Simulation of Stress and Deformation for a Duplex Stainless Steel Impeller during Casting and Heat Treatment Processes

A large-scale, thin wall duplex stainless steel impeller with complex geometry was deformed severely and unpredictably during casting and heat treatment processes resulted in dimensional failure for the final part. In this paper, the distortion of the impeller during casting and heat treatment was calculated. A commercial software, Experto-ViewCast, was used to simulate the transient heat transfer, solidification and mechanical behaviors during the casting and the heat treatment process. The coupled set of governing differential equations for mass, energy and mechanical balance were solved by finite control volume and finite element method. A thermoelastic-visco-plastic rheological model was used to compute the constrained shrinkage of the casting. At each time increment, a coupling of the heat transfer and mechanics was performed. Comparison of the experimental measurements with the model predictions showed good agreement. From the calculated displacements of key points of the blade, the proper inverse displacements were determined to provide an optimum casting pattern and to achieve a uniform and reasonable machining allowance for both faces of the blade.

Dynamic of Non-Autonomous Vector Infectious Disease Model with Cross Infection

In the article, we established a non-autonomous vector infectious disease model, studied the long-term dynamic behavior of the system, and obtained sufficient conditions for the extinction and persistence of infectious diseases by constructing integral functions.

南辕北辙,还是在路上?——中国会计研究国际化进程观察

本文回顾了20世纪90年代中期以来的中国会计研究国际化进程,基于中国(不含港澳台地区)高校在国际五大会计期刊的论文发表和引用情况分析了国际化进程的成就和不足。基本结论是,二十余年来中国会计研究的国际化进程成效显著,体现在中国高校在国际五大会计期刊的论文发表产能显著提升。然而,在发表产能显著提升的同时,是在研究人员来源、研究对象和研究内容上本土性特征的显著下降,以及学术影响力的缺失。如果说中国会计研究国际化进程的初衷是通过学习借鉴国际上的科学研究方法以更好地开展中国问题研究,从而服务于中国的转型和发展,那么二十余年来的国际化进程已经呈现出令人遗憾的'南辕北辙'的局面。本文进而提出了以中国问题、研究的重要性、原创性和影响力为核心尺度的内容导向学术评价制度改革方向。

核准制下IPO从严审核的代价——最严发审委的发审效果研究

本文基于核准制下"大发审委"(第十七届发行审核委员会)从严审核的自然实验,考察了IPO(initial public offering,首次公开募股)从严审核的资源配置效应。研究发现,在严格的问责制度下,中国证券监督管理委员会发行审核委员会(简称发审委)倾向于显著地降低发审通过率,同时规避自身风险,选择财务指标良好的低风险企业(营业收入增长高的企业),而回避高风险但可能具有发展潜力的企业(研发费用高的企业)。其次,在从严审核时期,拟上市企业承担了更多的IPO费用以提高IPO审核通过率。此外,相较非"大发审委"时期的过会企业,"大发审委"审核通过的企业更可能出现业绩变脸,这样的审核标准忽略了企业未来的成长性和发展潜力,没有得到投资者的认同,市场表现也更差。

Founder Control,Ownership Structure and Firm Value:Evidence from Entrepreneurial Listed Firms in China

In emerging markets, the deviation between the ultimate controlling shareholders' voting rights and their cash flow rights(hereafter "DVC") in the listed firms is quite prevalent. DVC could be introduced due to the ultimate controlling shareholders' opportunistic incentives, as well as by their incentives to improve firm efficiency. This study uses 229 listed firms ultimately controlled by individuals or families(hereafter "entrepreneurial firms") for 2004 in China, to investigate the effect of DVC on firm value and to determine whether it is different between founder and non-founder controlled firms. We find that DVC has a positive effect on firm value for founder controlled firms. This result implies that investors believe that their interests are better protected by founder controlled firms than by non-founder controlled firms.

Emerging roles of podoplanin in vascular development and homeostasis

Podoplanin （PDPN） is a mucin-type O-glycoprotein expressed in diverse cell types, such as lymphatic endothelial cells （LECs） in the vascular system and fibroblastic reticular cells （FRCs） in lymph nodes. PDPN on LECs or FRCs activates CLEC-2 in platelets, triggering platelet activation and/or aggregation through downstream signaling events, including activation of Syk kinase. This mechanism is required to initiate and maintain separation of blood and lymphatic vessels and to stabilize high endothelial venule integrity within lymph nodes. In the vascular system, normal expression of PDPN at the LEC surface requires transcriptional activation of Pdpn by Proxl and modification of PDPN with core 1-derived O-glycans. This review provides a comprehensive overview of the roles of PDPN in vascular development and lymphoid organ maintenance and discusses the mechanisms that regulate PDPN expression related to its function.

IFRS adoption in China and foreign institutional investments

We examine the effectiveness of China’s IFRS adoption from the perspective of an important set of financial report users, foreign institutional investors. We find that foreign institutional investment does not increase after China’s IFRS adoption, and some evidence that it actually declines, particularly among firms with weaker incentives to credibly implement IFRS, or with greater ability to manipulate IFRS’s fair value provisions. We also find that the association between earnings and returns generally declines after IFRS adoption, consistent with reduced earnings quality. In addition, we find that foreign institutional investors’ returns decrease after China’s IFRS adoption. Finally, the decline in foreign institutional investment is greater among investors from countries with weak institutions that have also adopted IFRS. Taken together, our evidence suggests that the weak institutional infrastructure in China’s transitional economy impairs IFRS’s intended goal of attracting institutional investment through improved financial reporting quality. Further, financial information users’ home country institutions and IFRS adoption experience affect the effectiveness of IFRS adoption.

QFII如何投资中国资本市场——来源国家或地区的制度环境与QFII投资偏好

本文从QFII来源国家或地区的制度环境这一全新视角,考察QFII对中国资本市场的投资偏好。研究发现:(1)来自制度环境较好国家或地区的QFII更加规避公司治理弱(更多关联交易)和透明度低的上市公司;(2)来自制度环境较好国家或地区的QFI更加偏爱公开信息披露环境好(上市公司有微博或微信、更多的分析师跟踪、聘请国际“四大”会计师事务所)的上市公司;(3)来自制度环境较好国家或地区的QFII的上述投资偏好特征,虽然未带来显著更高的投资业绩,但能够显著规避未来异常的市场风险和经营风险。本文揭示了一种新的QFII“本土”偏好,同时对于中国资本市场的高水平对外开放具有启示。