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31.
采用2003-2012年中国除西藏外30个省市自治区的面板数据,考察信息通信技术渠道国际R & D溢出效应。运用面板单位根检验、协整检验、相关性分析、格兰杰因果检验、随机效应模型等计量方法,研究中国通过信息通信技术渠道获得的国际R & D溢出与当地全要素生产率之间的关系;建立Hansen非动态面板门槛模型,采用稳健标准差回归,检验各省份由信息通信技术渠道获得的国际R & D溢出门槛效应,并从产业转型升级和信息化建设角度分析存在门槛效应的原因。结果表明,中国大部分省份通过信息通信技术渠道获取的国际R & D溢出与全要素生产率有正相关关系;通过信息通信技术渠道获得的国际R & D溢出对当地技术进步的影响存在明显的地区差异和门槛效应。  相似文献   
32.
3D打印技术的发展使著作权法上的复制变得更为高效便捷,由此产生了一系列亟待梳理和解决的问题。基于3D打印技术原理,可将其分为输入和输出两个环节。在输入环节,对CAD文件的作品类型进行规制,采用视觉标准界定立体作品,并以“美术作品+模型作品”的思路进行综合保护;在输出环节,3D打印属于复制,且可以实现从平面到立体和从立体到立体的复制形态,复制权的控制范围应不限于现行法律所列举的方式。针对3D打印技术在网络传播中的侵权风险,应对合理使用中的私人复制予以限制,灵活运用“三步检验标准”对合理性进行审查。3D打印在著作权法方面并未引发新的法律问题,现行制度已存在包容空间,不必为其特设著作权新规,通过对现有规则的解释和借助已有案例的适用经验便能解决可预见的著作权法争端。  相似文献   
33.
This paper analyses child labour participation and its key determinants using data sets from Peru and Pakistan. The results include tests of the ‘Luxury’ and ‘Substitution’ hypotheses that play key roles in recent studies on child labour and child schooling. The results reject both hypotheses in the context of child labour in Pakistan and suggest that income and related variables do not have the expected negative effect on children's work input. Rising wages of adult female labour in Pakistan, and falling adult male wage in Peru lead to increased participation of children in the labour market. The results on the combined country data formally establish the presence of strong individual country effects in the estimated regressions. For example, ceteris paribus, a Peruvian child is more likely to experience schooling than a Pakistani child. However, both countries agree on the positive role that adult female education and infrastructure investment in basic amenities can play in discouraging child labour and encouraging child schooling. Received: 24 August 1998/Accepted: 10 March 1999  相似文献   
34.
This paper analyses how governments should tax labour income accruing to a group of highly skilled and geographically mobile individuals who divide their time or career between several jurisdictions. The analysis differs from previous models on migration and taxation by addressing optimal regulation when agents work for several principals. Optimal taxation is developed for social welfare functions with exogenous and endogenous welfare weights. Marginal income taxes are applied for screening purposes, and the rates are lower with endogenous than with exogenous welfare weights. Received: 22 January 1998/Accepted: 3 July 1999)  相似文献   
35.
Objective: The objective of this study is to investigate the impact of metabolic status on associations of serum vitamin D with hypogonadism and lower urinary tract symptoms (LUTS)/benign prostatic hyperplasia (BPH).

Patients and methods: A total of 612 men underwent physical examination, biochemical/hormonal blood testing, and transrectal prostate ultrasound. Moreover, the subjects filled out standard questionnaires for identification and grading of LUTS and hypogonadism symptoms. Parameters were statistically compared with independent t-tests and correlation analyses.

Results: Vitamin D levels positively correlated with total testosterone (TT) but not with prostate volume or International Prostate Symptom Score (IPSS). Patients with metabolic syndrome had significantly lower vitamin D levels, which were not correlated with TT, prostate volume, or IPSS. However, vitamin D was positively correlated with TT, and negatively correlated with prostate volume and quality-of-life IPSS in subjects without metabolic syndrome.

Conclusion: The clinical usefulness of vitamin D for treatment of hypogonadism or LUTS/BPH varies according to metabolic status.  相似文献   

36.
3D printing (3DP) has been heralded as a revolutionary technology that can alter the way production is organized across time and space – with important redistributive effects on geography and size of production activities. In this article, we examine the impacts that a widespread adoption of 3DP could have on restructuring, upgrading and distributing value added along manufacturing global value chains (GVC) – with brief examples from the aerospace and automotive industries. We highlight two possible scenarios for GVCs – a complementarity scenario of 3DP and traditional manufacturing overlapping, which would reproduce power relations in GVCs and the current distribution of value added in a ‘smiling curve’; and a substitution scenario of 3DP partly or fully superseding traditional manufacturing, which would have more transformational effects in terms of ‘rebundling’ activities, regionalizing or localizing GVCs, and flattening the smiling curve into a ‘smirk’.  相似文献   
37.
在分析政府补贴政策的特征及其影响企业真实创新绩效的理论机制的基础上,运用A股上市公司数据,检验了政府补贴对企业真实创新绩效的直接和传导效应。研究发现:政府补贴对企业真实创新绩效具有激励效应,且国有企业较非国有企业的创新效应更强;研发资本要素市场扭曲能够强化政府补贴激励企业真实创新绩效的调节作用,并与产权性质联合调节政府创新补贴效果;创新投入与融资约束在政府补贴对企业真实创新绩效的影响中起部分中介效应;政府补贴对企业创新持续性具有负向抑制效应,政府补贴效果受到研发资本要素市场扭曲和产权性质明显的负向调节作用,且创新投入与融资约束在政府补贴对企业持续性创新的影响中起部分中介效应。  相似文献   
38.
3D细节描写是一种立体的3D视角,能将平面的画面直观地显现成3维的立体画面。《丰乳肥臀》中有大量的细节描写,有一部分是明显的3D描写,让读者融入情景、直观感受。尽管莫言不是有意识进行3D描写,但有意识地立体地细节描写写出了3D效果。  相似文献   
39.
This study examined the differences in risk behavior between men and women using a household survey that captured the risk preferences of two members in a household and recorded wealth at the individual level instead of the usual approach of representing wealth at the household level. After controlling for commonly used explanatory variables, such as gender, education, age, and wealth, household fixed effects explain about 15% of the variation in risk behavior. This highlights the magnitude of household effects in shaping one’s risk behavior. In general, females in the study area are more risk averse than males based on a risk game with real payout. The gender differences disappear when focusing on only the top land owners. However, even in those cases, females consider themselves more risk averse, supporting results from previous studies that link culture and societal norms to the gender differences in risk behavior.  相似文献   
40.
The ability to influence behaviour is central to many of the key policy challenges in areas such as health, finance and climate change. The usual route to behaviour change in economics and psychology has been to attempt to ‘change minds’ by influencing the way people think through information and incentives. There is, however, increasing evidence to suggest that ‘changing contexts’ by influencing the environments within which people act (in largely automatic ways) can have important effects on behaviour. We present a mnemonic, MINDSPACE, which gathers up the nine most robust effects that influence our behaviour in mostly automatic (rather than deliberate) ways. This framework is being used by policymakers as an accessible summary of the academic literature. To motivate further research and academic scrutiny, we provide some evidence of the effects in action and highlight some of the significant gaps in our knowledge.  相似文献   
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