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1.
To spur technology transfer, emerging market policymakers often require foreign firms to form joint ventures (JVs) with domestic firms. Through knowledge spillovers, JVs may reduce technology acquisition costs for domestic firms. Yet domestic firm rents from JVs could discourage innovation through a cannibalization effect. Which force dominates is an empirical question. I address it with novel data on China's auto sector. In response to fuel economy standards requiring firms to upgrade technology or sacrifice quality, firms with JVs reduced quality and price relative to their counterparts. Consistent with cannibalization, firms with JVs drive the negative effect.  相似文献   
2.
In fast-paced and knowledge-intensive environments, licensing partnerships can be powerful levers for market expansion. Research on the management of technology-oriented licenses has nonetheless pointed out the risks of corrosive disputes caused by conflicting interests or misunderstandings among licensing partners. The choice made ex ante on mechanisms for resolving potential disputes is of prime importance in the execution of licensing exchanges. Although the legal literature has widely emphasized the advantages of arbitration towards litigation, public ordering remains the “default” option in managers’ eyes. By adopting a transaction cost economics logic, our study explores the conditions under which licensing partners may prefer arbitration over public ordering during the contractual-design phase. In accordance with our theoretical arguments, findings show that the occurrence of arbitration provisions increases when the coordination orientation adopted by licensing partners is extensive. In situations where both monitoring and coordination orientations are simultaneously extensive, results reveal a greater propensity to prefer arbitration over public ordering. Our research therefore supports the view that corporate decision-makers tend to favor the conciliatory stance and compromising awards typically associated with arbitration, only when exchanges are expected to be highly coordinative. Their preference for arbitration over litigation is magnified when the coordination orientation develops alongside the monitoring orientation.  相似文献   
3.
USB接口在数据采集系统中的应用   总被引:2,自引:0,他引:2  
唐祎玲 《科技广场》2005,(12):67-69
通用串行总线(USB)作为一种标准的计算机可以支持快速、双向、同步传输及热插拔,使用灵活、方便。本文介绍了一个USB数据采集系统的设计过程,重点阐述了USB通信接口和USB设备软件设计两个部分。  相似文献   
4.
本文在介绍USB接口基础上,提出一种AT89C52扩展USB接口的实现方法。并指出由于USB接口使用方便、支持热插热拔,AT89C52扩展了USB功能有利于进一步拓展其应用,因而具有广阔的应用前景。  相似文献   
5.
目的 通过检测急性白血病(AL)患者静脉血清中血管内皮生长因子(VEGF)和 白细胞介素12(IL-12)的含量,探讨VEGF和IL-12在急性白血病中的含量及临床意义。方法 应用定量酶联免疫吸附实验测定10例初诊未治、10例缓解期、5例复发患者和9例正常对照血清中VEGF和IL-12的含量。结果 初诊未治组的VEGF含量(521.06±163.85pg/ml)明显高于缓解组(307.62±55.40pg/ml)及对照组(262.01±141.66pg/ml)(p均<0.05)。对照组的IL-12水平(58.96±38.11pg/ml)与初诊复发组(初诊未治组与复发组的合称32.51±14.58pg/ml)、缓解组(71.67±119.09pg/ml)之间均有显著性差异(p均<0.05)。正常对照组VEGF的含量与IL-12之间存在负相关性。结论 VEGF和IL-12与AL的病情变化有一定的关系。  相似文献   
6.
Acetaminophen (APAP) a commonly used drug for decrease the fever and pain but is capable to induced hepatotoxicity at over dose. This study was carried out to investigate the effect of APAP on the expression of anti-apoptotic and antioxidative defense genes, and whether aldose reductase over-expressing plasmid capable to protect against APAP-induced oxidative stress and cell death. APAP treatment induced oxidative stress and hepatotoxicity, and significantly increased aldose reductase mRNA and protein expression in mouse hepatocyte (AML-12). Unexpectedly, AML-12 cells over-expressing aldose reductase augmented APAP-induced reduction in cell viability, reactive oxygen species (ROS) production, glutathione (GSH) depletion and glutathione S-transferase A2 expression. Moreover, over-expression of aldose reductase potentiated APAP induced reduction on proliferating cell nuclear antigen, B cell lymphoma-extra large (bcl-xL), catalase, glutathione peroxidase-1 (GPx-1) and abolished APAP-induced B-cell lymphoma 2 (bcl-2) inductions. Further, over-expression of aldose reductase significantly abolished AMP activated protein kinase (AMPK) activity in APAP-treated cells and induced p53 expression. This results demonstrate that APAP induced toxicity in AML-12, increased aldose reductase expression, and over-expression of aldose reductase render this cell more susceptible to APAP induced oxidative stress and cell death, this probably due to inhibition AMPK or bcl-2 activity, or may due to competition between aldose reductase and glutathione reductase for NADPH.  相似文献   
7.
Adverse Childhood Experiences (ACEs) are prevalent in the population and linked to various negative long-term health and social consequences. However, due to the retrospective nature of most studies on the topic, little is currently known regarding ACEs' immediate health impact. This study aims to provide insight into this area by examining the association between a new measurement, Adverse Family Experiences (AFEs), and flourishing amongst children ages 6–17 years in the United States. Data from the 2011/12 National Survey of Children's Health were analyzed. Adjusted prevalence ratios assessed flourishing by the number of AFEs (0 events versus 1, 2, 3/3+) controlling for individual/household characteristics. A sub-analysis examined characteristics of flourishing children ages 12–17 years with 3/3+ AFEs. The results showed children with 1 AFE (APR = 0.87; 95% CI = 0.83-0.91), 2 AFEs (0.74; 0.69–0.79), and 3/3+ AFEs (0.68; 0.62–0.72) were less likely to flourish compared to those without any AFEs. Sub-analysis of children ages 12–17 years with 3/3+ AFEs revealed a higher proportion of flourishing children volunteering, participating in extracurricular activities, and working for pay compared to those who did not flourish. Findings show significant differences in flourishing by number of AFEs and suggest that social connectedness may play a role in determining flourishing amongst children with 3/3+ AFEs. Furthermore, the results highlight the potential importance of identifying children with high AFE counts and helping them build resilience outside of the home.  相似文献   
8.
Inquiry-based education receives much attention in educational practice and theory, since it provides pupils and teachers with opportunities to actively engage in collaboratively answering questions. However, not only do many teachers find this approach demanding, it also remains unclear what they should do to foster this type of education in their classrooms. Our research question was: Which teaching strategies are used by K-12 teachers when promoting inquiry-based education in their classrooms and what are the reported outcomes?After searching for empirical studies on this topic, we examined 186 studies investigating different ways in which teachers can promote inquiry-based education. Analyses revealed varying teaching strategies, differing with regard to direction (teacher directed, student directed and mixed) and different perspectives of regulation (meta-cognitive, conceptual, and social regulation). Results show that important teacher strategies in metacognitive regulation are: focussing on thinking skills, developing a culture of inquiry, supporting inquiry discourse, and promoting nature of science; in conceptual regulation: providing information on the research topic and focussing on conceptual understanding; and in social regulation: bridging the gap between high and low achievers, organizing student learning in groups and focussing on collaboration processes.  相似文献   
9.
水体中维生素B_(12)含量的提高是水花发生的重要因子之一,采用VitB_(12)的细菌生物测试法,证明VitB_(12)含量具有生物内源性质,即部分水花藻类具产生VitB(12)的能力,对进一步研究水花形成机制及控制水花发生起促进作用。  相似文献   
10.
研究综合了来自中国大陆18570名3-12岁儿童的焦虑与父母教养方式相关的30项研究的数据,通过元分析的方法考查了二者相关的强度,并分析影响相关强度的因素。从总体上来说,儿童焦虑与父母教养方式存在弱相关;父母教养方式类型、儿童年龄、父母性别会对二者关系产生调节作用。建议在教养儿童过程中要采用正向的教养方式,要给予年幼儿童充分的独立自主的权利和自由,鼓励父亲参与教养,这有利于降低儿童的焦虑水平。  相似文献   
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