The long march to catch-up: A history-friendly model of China’s mobile communications industry

This paper develops a history-friendly model of the process of catch-up by Chinese firms in the mobile communications industry. It aims to explain how the sectoral environment in terms of segmented markets and generational technological change facilitated the catch-up of domestic firms with respect to foreign multinationals. Segmented markets provided a nurturing environment in peripheral markets for the survival of domestic firms starting with low level capabilities in their infant stage. Generational technological change opened windows of opportunities for domestic firms to catch-up with foreign multinationals in new product segments. Segmented markets and generational technological change allowed domestic firms to leverage their initial advantages in peripheral markets to catch-up in core markets. Counterfactual simulations highlight that the process of catch-up was facilitated by relatedness across technological generations. This paper contributes to the literature on catch-up and industry evolution by illustrating the role of technological change and market regimes in the process of catching-up.     

The impact of patent protection and financial development on industrial R&D

Stronger protection of patent rights is thought to spur innovation through securing returns to R&D investments. Those investments must be financed, however, suggesting that the responsiveness of R&D to patent reforms varies with financial development levels. We examine the joint impact of domestic and international financial-market development and patent protection on R&D intensities in 22 manufacturing industries in 20 OECD countries for the period 1990-2009. We show that stronger patent rights increase R&D intensities in patent-intensive industries, accounting for the need for external financing and the amount of tangible assets. The primary impact varies across types of financial development: patent protection raises R&D in high-patent industries where countries have more limited equity and credit markets. In contrast, in countries with more developed bond markets industry R&D is more sensitive to patent rights. Interestingly, patent rights in countries that are more exposed to foreign direct investment increase R&D intensities at all levels of financial development.     

全脑缺血再灌注大鼠海马Caspase-3、8表达及HWTX-I神经保护机制的研究

为观察虎纹捕鸟蜘蛛毒素-I(HWTX-I)对全脑缺血再灌注大鼠海马组织凋亡相关因子Caspase-3、Cas-pase-8mRNA及蛋白表达的影响。将SD大鼠随机分为假手术组、生理盐水组及用药组;采用改良的Pulsinelli"四血管阻断"法制备全脑缺血损伤模型并结合蛛网膜下腔置管术;免疫组织化学法检测Caspase-3、Caspase-8蛋白水平的表达;RT-PCR法检测凋亡相关因子Caspase-3、Caspase-8mRNA表达变化。免疫组织化学法检测结果显示,HWTX-I能显著降低全脑缺血再灌注大鼠海马组织CA1区Caspase-3、Caspase-8蛋白水平的表达(P<0.05);RT-PCR结果显示,HWTX-I能显著降低全脑缺血及再灌注大鼠海马组织Caspase-3、Caspase-8核酸水平的表达(P<0.05)。提示:HWTX-I蛛网膜下腔用药对全脑缺血再灌注SD大鼠海马组织的保护作用可能通过抑制凋亡相关因子Caspase-3、Caspase-8mRNA和蛋白表达,从而发挥其抗脑缺血再灌注损伤的保护作用。     

十运会与雅典奥运会男子十项全能决赛成绩比较分析

通过运用文献资料法、数理统计法、比较分析法,对十运会与雅典奥运会男子十项全能决赛的成绩进行了比较分析。研究表明:我国男子十项全能运动员总分、各单项成绩及技术等级与世界优秀运动员相比差距明显,在某些项目上差距更大;我国男子十项全能运动员各单项的得分率与世界优秀运动员相比基本一致。旨在通过比较分析,使相关人士认识到我国男子十项全能运动的现状,采取措施,尽快缩短与世界先进水平的差距。     

Controllability of mixed Volterra-Fredholm-type integro-differential systems in Banach space

Dhakne and Kendre [On abstract nonlinear mixed Volterra-Fredholm integro-differential equations, Presented Paper in the International Conference at IIT-Bombay, 11-13 December, 2004] has proved the existence of the abstract nonlinear mixed Volterra-Fredholm integro-differential system of the type

     

具分布时滞中立型微分方程的振动性

讨论了一阶具分布时滞中立型微分方程[x(t) -λ∫τοp(t,θ)x(t -θ)dθ]′ ∫σοq(t,s)x(t -s)ds=0 ,建立了该方程振动的充分条件     

Inheriting knowledge and sustaining relationships: What stimulates the innovative performance of small software firms in the Netherlands?

Previous studies showed that firms established by experienced founders have higher survival rates and employment growth, but the potential effect of pre-entry experiences on innovation remains unclear. Using an original dataset, we examine the effect of founder's experiences, the relationship with the founder's previous employer and spatial proximity to the previous workplace on the innovative performance of small software firms in the Netherlands. Apart from entrepreneurial experiences, the results suggest no effect of pre-entry experiences. Continued contacts with the founder's previous employer appear to limit the firm's innovative performance, but firms do benefit from being established near the previous workplace.     

多时滞Logistic差分方程正周期解的存在性

本文研究多时滞Logistic差分方程u(k+1)=u(k)exp{a(k)-∑mj=1bj(k)u(k-τj(k))}运用重合度理论,证明了方程至少存在一个正周期解.     

Scientific collaboration of new 10 EU countries in the field of social sciences

The paper presents bibliometric analysis of scientific collaboration of new 10 countries EU in the field of social sciences. Material for this analysis was drawn from DB SSCI. The states as wholes are considered here as participants of collaboration. The results are mapped in a chart of counter to country links.     

蜂王浆制品中10-HDA测定

用高效液相色谱法(HPLC)测定蜂王浆制品中10-羟基-2-癸烯酸(10-HDA)。色谱柱Zorbax ODS 25cm×4.6mm (i.d),用0.033mol/L盐酸/甲醇(1:1 V/V)作流动相洗脱,流速为0.8ml/min,检测波长为210nm。外标法蜂面积定量,标准曲线相关系数为0.999977,变异系数(n=6)为1.5％。