论人力资本积累的机理及方式

人力资本积累是一个国家和地区兴盛发展的关键,但国内外对人力资本积累的机理研究还有待深入。本文分析了人力资本积累的过程及其影响因素,从人力资本存量和增量两个方面入手,提出了人力资本积累的基本原理和方法。     

Separation of sperm and epithelial cells based on the hydrodynamic effect for forensic analysis

In sexual assault cases, forensic samples are a mixture of sperm from the perpetrator and epithelial cells from the victim. To obtain an independent short tandem repeat (STR) profile of the perpetrator, sperm cells must be separated from the mixture of cells. However, the current method used in crime laboratories, namely, differential extraction, is a time-consuming and labor-intensive process. To achieve a rapid and automated sample pretreatment process, we fabricated a microdevice for hydrodynamic and size-based separation of sperm and epithelial cells. When cells in suspension were introduced into the device''s microfluidic channels, they were forced to flow along different streamlines and into different outlets due to their different diameters. With the proposed microdevice, sperm can be separated within a short period of time (0.5 h for a 50-μl mock sample). The STR profiles of the products in the sperm outlet reservoir demonstrated that a highly purified male DNA fraction could be obtained (94.0% male fraction). This microdevice is of low-cost and can be easily integrated with other subsequent analysis units, providing great potential in the process of analyzing sexual assault evidence as well as in other areas requiring cell sorting.     

The construction of an interfacial valve-based microfluidic chip for thermotaxis evaluation of human sperm

Thermotaxis has been demonstrated to be an important criterion for sperm evaluation, yet clinical assessment of thermotaxis capacity is currently lacking. In this article, the on-chip thermotaxis evaluation of human sperm is presented for the first time using an interfacial valve-facilitated microfluidic device. The temperature gradient was established and accurately controlled by an external temperature gradient control system. The temperature gradient responsive sperm population was enriched into one of the branch channels with higher temperature setting and the non-responsive ones were evenly distributed into the two branch channels. We employed air-liquid interfacial valves to ensure stable isolation of the two branches, facilitating convenient manipulation of the entrapped sperm. With this device, thermotactic responses were observed in 5.7%-10.6% of the motile sperm moving through four temperature ranges (34.0-35.3 °C, 35.0-36.3 °C, 36.0-37.3 °C, and 37.0-38.3 °C, respectively). In conclusion, we have developed a new method for high throughput clinical evaluation of sperm thermotaxis and this method may allow other researchers to derive better IVF procedure.     

人工情感与人工智能应用研究

生活世界中人工情感研发得到快速发展,但还不能比及人类情感。语境残破和缺身涉入是人工情感不及人类情感真挚、真切的两个重要原因。建构语境与虚拟身体的协同创新有助于增强人工情感的逼真度。人工情感在教育、客服、营销、制造、安防等领域的应用,将有助于提高人机交互的有效性、体验性和真实性。随着人工情感的增强,我们既要积极支持,同时也要做好应对因人工情感所带来各种风险的防控。     

Morphology modulation of artificial muscles by thermodynamic-twist coupling

Human muscles can grow and change their length with body development;therefore,artificial muscles that modulate their morphology according to changing needs are needed.In this paper,we report a strategy to transform an artificial muscle into a new muscle with a different morphology by thermodynamic-twist coupling,and illustrate its structural evolution during actuation.The muscle length can be continuously modulated over a large temperature range,and actuation occurs by continuously changing the...     

Measurement of fluid flow generated by artificial cilia

We observed and measured the fluid flow that was generated by an artificial cilium. The cilium was composed of superparamagnetic microspheres, in which magnetic dipole moments were induced by an external magnetic field. The interaction between the dipole moments resulted in formation of long chains-cilia, and the same external magnetic field was also used to drive the cilia in a periodic manner. Asymmetric periodic motion of the cilium resulted in generation of fluid flow and net pumping of the surrounding fluid. The flow and pumping performance were closely monitored by introducing small fluorescent tracer particles into the system. By detecting their motion, the fluid flow around an individual cilium was mapped and the flow velocities measured. We confirm that symmetric periodic beating of one cilium results in vortical motion only, whereas asymmetry is required for additional translational motion. We determine the effect of asymmetry on the pumping performance of a cilium, verify the theoretically predicted optimal pumping conditions, and determine the fluid behaviour around a linear array of three neighbouring cilia. In this case, the contributions of neighbouring cilia enhance the maximal flow velocity compared with a single cilium and contribute to a more uniform translational flow above the surface.     

The ethical use of artificial intelligence in human resource management: a decision-making framework

Ethics and Information Technology - Artificial intelligence (AI) is increasingly inputting into various human resource management (HRM) functions, such as sourcing job applicants and selecting...     

利用包裹体分析鄂尔多斯盆地上古生界油气充注史与古流体势

对鄂尔多斯盆地上古生界110块砂岩样品中流体包裹体进行了荧光、温度和流体势分析。系统分析表明，鄂尔多斯盆地上古生界天然气具有多阶连续性运聚特征，虽可划分6期，但应为多期充注一期成藏。各区块不断运移平衡连续成藏。不同时期流体势走向不尽相同，榆林、神木、乌审旗等地区为油气长期指向区。     

人工智能驱动的生命科学研究新范式

生物技术和信息技术的迅速发展,使生命科学进入了数据爆发的新时代,传统生命科学研究范式难以在日益增长的生物大数据中揭示生命复杂系统的本质规律。随着人工智能（AI）在生命科学研究领域持续取得颠覆性突破,AI驱动的生命科学研究新范式呼之欲出。文章通过深入剖析AI驱动的生命科学研究的典型范例,提出了生命科学研究新范式的内涵和关键要素,阐述并讨论了新范式下的生命科学研究前沿和我国面临的挑战。     

异鼠李素对人鼻咽癌CNE-1细胞增殖的影响

目的:观察异鼠李素对鼻咽癌CNE-1细胞生长及增殖的抑制作用。方法:用不同浓度(10、30、50、70、90μg/m L)的异鼠李素处理人鼻咽癌CNE-1细胞,在不同时间点分别采用CCk-8法检测测细胞生长抑制率;台盼蓝染色测细胞活力;平皿培养测细胞集落形成能力。结果:与正常组相比,异鼠李素处理CNE-1细胞48h后,细胞生长抑制率明升高(p0.05或p0.01);用药物处理细胞6d,随着时间的延长,细胞生长活力逐渐降低;药物处理7天后,药物处理组细胞集落形成能力明显低于正常组(p0.05或p0.01)且以上方法都显示在一定范围内,异鼠李素对CNE-1细胞的生长及增殖抑制作用呈剂量依赖性。结论:异鼠李素可明显抑制鼻咽癌CNE-1细胞的生长和增殖。     

Inducing self-rotation of cells with natural and artificial melanin in a linearly polarized alternating current electric field

The phenomenon of self-rotation observed in naturally and artificially pigmented cells under an applied linearly polarized alternating current (non-rotating) electrical field has been investigated. The repeatable and controllable rotation speeds of the cells were quantified and their dependence on dielectrophoretic parameters such as frequency, voltage, and waveform was studied. Moreover, the rotation behavior of the pigmented cells with different melanin content was compared to quantify the correlation between self-rotation and the presence of melanin. Most importantly, macrophages, which did not originally rotate in the applied non-rotating electric field, began to exhibit self-rotation that was very similar to that of the pigmented cells, after ingesting foreign particles (e.g., synthetic melanin or latex beads). We envision the discovery presented in this paper will enable the development of a rapid, non-intrusive, and automated process to obtain the electrical conductivities and permittivities of cellular membrane and cytoplasm in the near future.     

人工智能对学术出版流程的再造及知识服务提升

【目的】 为提升大数据时代学术出版系统内部生产管理流程的效率和对外信息服务的能力,探讨未来人工智能技术对学术出版流程的重构和知识服务能力的提升。【方法】 综合调查法、文献分析法等研究方法调研人工智能技术对学术出版流程的推进和知识服务能力的提升工作。【结果】 人工智能技术不仅可以加速学术传播,推动出版流程各个环节之间数据传递和支持,从而重构智能化的学术出版流程,实现出版流程的选题策划便捷化、编辑加工流程自动化、生产印刷流程按需化以及营销发行流程精准化,还可以大大提升学术出版的知识服务能力,实现知识服务的行为智能化、思维智慧化、场景可视化、途径多元化和传播生态化。【结论】 出版流程和知识服务与人工智能深度融合是学术出版的未来发展方向,也是学术出版系统从低层次传播到高层次服务的价值功能转型升级的必经之路。