中小型企业数字创新的价值链路径

在数字转型背景下,为帮助缺乏资源的中小型企业应对如何利用数字技术进行创新进而创造价值的机遇与挑战,基于创新价值链和网络理论建立中小型企业数字创新价值链模型,采用结构方程模型（SEM）和模糊集定性比较分析（fsQCA）,从数字产品创新、数字服务创新和商业模式创新3个维度以及商业关系网络和个人关系网络两类数字化网络,利用267家中小型企业的数据进行实证检验。结果表明：中小型企业采用数字技术与其数字化网络之间存在显著的正相关关系,其中个人关系网络对3个维度的创新均产生正向影响,商业关系网络对数字服务创新具有正向影响;数字产品创新与数字服务创新对中小型企业的经营能力均具有显著的正向影响,其中数字技术是核心条件。由此给出中小型企业在不同发展目标下可考虑的数字创新路径,并提出制定帮扶中小型企业提高数字技术采用的精准政策。     

Learning representations for quality estimation of crowdsourced submissions

The problem of quality estimation of crowdsourced work is of great importance. Although a variety of aggregation methods have been proposed to find high-quality structured claims in multiple-choice crowdsourcing tasks such as item labeling, they do not apply to more general tasks, such as article writing and brand design with unstructured submissions. One possibility to tackle this problem is to ask another set of crowd workers to review and grade each submission, essentially transforming unstructured submissions into structured ratings. Nevertheless, such an approach incurs unnecessary monetary cost and delay. In this paper, we address this problem by exploiting task requesters’ historical feedback and directly modeling the submission quality. We propose two embedding-based methods where the first one learns worker embedding and the second one learns both worker embedding and meta information embedding, with additional consideration of neighborhood similarity. Experimental results on three large-scale crowdsourcing data sets demonstrate that our embedding-based feature-learning methods perform much better than feature-engineering methods that use popular learning-to-rank algorithms. At the same time, our methods do not require additional crowdsourced grading.     

科协组织培育创新文化的路径探析

创新文化是与创新实践相关的,以追求变革、崇尚创新为基本理念和价值取向的文化形态的总和,包括与创新相关的理念、制度和环境等三个层面.中国科协面向建设世界科技强国的新征程,系统谋划,提出了到2050年建成世界科技创新文化高地的宏伟目标.科协组织要发挥自身优势,以科技工作者为本,在弘扬科学家精神、涵养优良学风、激发创新活力、建设创新制度、营造创新氛围等方面开展工作,着力培育创新文化.     

弹性杆轴向拉力测定实验中振动频率识别方法研究

用频率法测试两端固支的弹性杆轴向拉力时,试验机及其夹具的振动会对杆件振动信号的测量和识别造成干扰,容易导致振动频率及阶次误判;提出了利用弹性杆在无约束自由振动下的频率作为基准值,对实验中杆的振动频率进行修正的方法,得到了弹性杆准确的振动频率及阶次;并发现试验机及其夹具对于两端铰支弹性杆的振动频率的识别不会产生影响;随着弹性杆长径比的增加,试验机及其夹具对两端固支的弹性杆振动频率识别产生的干扰逐渐减小,当轴向拉力不断加大时,这种干扰也呈现下降趋势。     

Effect of lipopolysaccharide on the hemocyte apoptosis of Eriocheir sinensis

In the present study, we investigated the possible toxicity mechanism of lipopolysaccharide (LPS) extracted from Gram-negative bacteria in Eriocheir sinensis hemocytes. Apoptotic hemocytes and reactive oxygen species (ROS) production induced by the LPS were monitored by the combination of flow cytometry and microscope observation. It was shown that LPS induced serious damage on the DNA and morphological changes in hemocytes, including cell shrinkage, fracture of nucleus membrane, margination, condensation and fragmentation of chromatin, and formation of apoptotic bodies indicating obvious hemocyte apoptosis. As compared with the control group, the apoptotic cell ratio increased to 30.61% and 39.01% after 1-h exposure and 57.72% and 75.01% after 2-h exposure to 1 and 10 μg/ml LPS, respectively (P<0.05). Significant outburst of ROS production was observed in LPS-treated hemocytes with approximately 176.6% of relative dichlorofluorescein mean fluorescence at 1-h exposure, followed by a drastic decline (P<0.05). These results indicated that LPS would induce oxidative stress on hemocytes from E. sinensis and cause ROS burst, DNA damage, and subsequently apoptosis. The process of ROS-mediated apoptosis might be one of the potential toxicity mechanisms of LPS on crustacean hemocytes.     

Tissue-engineered composite scaffold of poly(lactide-<Emphasis Type="Italic">co</Emphasis>-glycolide) and hydroxyapatite nanoparticles seeded with autologous mesenchymal stem cells for bone regeneration

Objective

A new therapeutic strategy using nanocomposite scaffolds of grafted hydroxyapatite (g-HA)/poly(lactide-co-glycolide) (PLGA) carried with autologous mesenchymal stem cells (MSCs) and bone morphogenetic protein-2 (BMP-2) was assessed for the therapy of critical bone defects. At the same time, tissue response and in vivo mineralization of tissue-engineered implants were investigated.

Methods

A composite scaffold of PLGA and g-HA was fabricated by the solvent casting and particulate-leaching method. The tissue-engineered implants were prepared by seeding the scaffolds with autologous bone marrow MSCs in vitro. Then, mineralization and osteogenesis were observed by intramuscular implantation, as well as the repair of the critical radius defects in rabbits.

Results

After eight weeks post-surgery, scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) revealed that g-HA/PLGA had a better interface of tissue response and higher mineralization than PLGA. Apatite particles were formed and varied both in macropores and micropores of g-HA/PLGA. Computer radiographs and histological analysis revealed that there were more and more quickly formed new bone formations and better fusion in the bone defect areas of g-HA/PLGA at 2–8 weeks post-surgery. Typical bone synostosis between the implant and bone tissue was found in g-HA/PLGA, while only fibrous tissues formed in PLGA.

Conclusions

The incorporation of g-HA mainly improved mineralization and bone formation compared with PLGA. The application of MSCs can enhance bone formation and mineralization in PLGA scaffolds compared with cell-free scaffolds. Furthermore, it can accelerate the absorption of scaffolds compared with composite scaffolds.

     

基于网络舆情视角的我国转基因食品安全问题分析

基于网络舆情视角分析我国的转基因食品安全问题,发现网民对转基因食品的关注与目前我国主要存在转基因问题的食品领域相吻合,将2007-2013年我国转基因食品安全网络舆情的发展分为舆情萌芽阶段、舆情突发阶段、舆情发展阶段、舆情井喷阶段等4个阶段,构建了转基因食品安全网络舆情的传播路径,认为媒体和网民对转基因食品持有明显的负面态度,我国的转基因食品安全网络舆情环境不容乐观。对此,提出了相应的政策建议。     

基于WSR的我国马拉松猝死风险防范模式及机制研究

马拉松猝死风险防范对于我国马拉松赛事健康可持续发展、全面落实全民健身国家战略具有重要意义。运用文献资料法、归纳逻辑法在对加强马拉松猝死风险防范的动因进行解析与对WSR系统方法论特点及适用性进行分析的基础上，构建基于WSR的我国马拉松猝死风险防范模式，提出基于WSR的我国马拉松猝死风险防范机制。其中，马拉松猝死风险防范模式以零风险管理、让人民共享健康福祉为目标导向，以营造良好的马拉松文化底蕴为根基，采用PDCA范式对影响马拉松猝死“物理—事理—人理”风险因素进行全面防范、闭环管理。马拉松猝死风险防范机制以建立健全马拉松赛事运行机制、完善马拉松猝死风险预警机制、加强马拉松猝死风险评估机制、健全马拉松猝死风险应对机制与优化马拉松猝死风险防范协同机制为主要抓手，形成共建共治共享的马拉松猝死风险防范共同体，实现全风险、全要素、全主体、全过程的马拉松猝死风险防范治理格局。     

科技全球化背景下大数据研究合作网络的可视化分析

旨在揭示大数据研究中国家和机构间的合作模式和网络结构,发现主要参与国家和机构的主导地位,并利用科学地图来可视化这些合作特征.在了解大数据领域全球论文产出概况的基础上,应用网络特征指标分析大数据研究合作网络的结构特征及演化规律、主要国家与机构在合作网络中的地位及其作用,并通过VOSviewer软件以科学叠加图(overlay map)的形式对结果进行可视化.研究发现:全球大数据研究以国内合作尤其是机构内合作为主,国家和机构间合作的比重较低,随着时间推移,国际合作网络规模不断扩大,并逐渐向多元主导模式转变;中国、美国和英国在国际合作网络中占据核心地位、发挥桥梁作用;中国作者在国际合作网络中的主导性较高,中国科学院、德克萨斯大学和清华大学是最为活跃的参与机构.