Effects of postgraduate education on technological innovation: a study based on the spatial Durbin model

Huimin Xiao,Jun Mao 서울대학교 교육연구소 2021 Asia Pacific Education Review Vol.22 No.1

Based on the spatial Durbin model, this paper explored postgraduate education’s influence and spatial effects on technological innovation. Using China’s provincial panel data from 2004 to 2018, study results revealed that distribution of postgraduates in China showed spatial autocorrelation and non-equilibrium. Overall, postgraduate education positively impacted technological innovation. The study measured spatial spillover using three spatial weight matrices, finding that postgraduate education significantly promoted innovation in similar provinces. The spatial spillover effect in the economic matrix was stronger than that in the adjacent matrix. In economic and economic-geographical matrices, postgraduate education’s spatial spillover effect was stronger than its direct effect. This paper can deepen understanding of characteristics and functions of postgraduate education in a rapidly developing economy.

Ginsenoside Rb1 exerts neuroprotective effects through regulation of Lactobacillus helveticus abundance and GABAA receptor expression

Huimin Chen,Jiajia Shen,Haofeng Li,Xiao Zheng,Dian Kang,Yangfan Xu,Chong Chen,Huimin Guo,Lin Xie,Guangji Wang,Yan Liang 고려인삼학회 2020 Journal of Ginseng Research Vol.44 No.1

Background: Ginsenoside Rb1 (Rb1), one of the most abundant protopanaxadiol-type ginsenosides, exertsexcellent neuroprotective effects even though it has low intracephalic exposure. Purpose: The present study aimed to elucidate the apparent contradiction between the pharmacokineticsand pharmacodynamics of Rb1 by studying the mechanisms underlying neuroprotective effects ofRb1 based on regulation of microflora. Methods: A pseudo germ-free (PGF) rat model was established, and neuroprotective effects of Rb1 werecompared between conventional and PGF rats. The relative abundances of common probiotics werequantified to reveal the authentic probiotics that dominate in the neuroprotection of Rb1. The expressionsof the gamma-aminobutyric acid (GABA) receptors, including GABAA receptors (a2, b2, and g2) andGABAB receptors (1b and 2), in the normal, ischemia/reperfusion (I/R), and I/RþRb1 rat hippocampus andstriatum were assessed to reveal the neuroprotective mechanism of Rb1. Results: The results showed that microbiota plays a key role in neuroprotection of Rb1. The relativeabundance of Lactobacillus helveticus (Lac.H) increased 15.26 fold after pretreatment with Rb1. I/R surgeryinduced effects on infarct size, neurological deficit score, and proinflammatory cytokines (IL-1b, IL-6, andTNF-a) were prevented by colonizing the rat gastrointestinal tract with Lac.H (1 109 CFU) by gavage 15d before I/R surgery. Both Rb1 and Lac.H upregulated expression of GABA receptors in I/R rats. Coadministrationof a GABAA receptor antagonist significantly attenuated neuroprotective effects of Rb1 and Lac.H. Conclusion: In sum, Rb1 exerts neuroprotective effects by regulating Lac.H and GABA receptors ratherthan through direct distribution to the target sites.

Ginsenoside Rb1 exerts neuroprotective effects through regulation of Lactobacillus helveticus abundance and GABA<SUB>A</SUB> receptor expression

Huimin Chen,Jiajia Shen,Haofeng Li,Xiao Zheng,Dian Kang,Yangfan Xu,Chong Chen,Huimin Guo,Lin Xie,Guangji Wang,Yan Liang 고려인삼학회 2020 Journal of Ginseng Research Vol.44 No.1

Background: Ginsenoside Rb1 (Rb1), one of the most abundant protopanaxadiol-type ginsenosides, exerts excellent neuroprotective effects even though it has low intracephalic exposure. Purpose: The present study aimed to elucidate the apparent contradiction between the pharmacokinetics and pharmacodynamics of Rb1 by studying the mechanisms underlying neuroprotective effects of Rb1 based on regulation of microflora. Methods: A pseudo germ-free (PGF) rat model was established, and neuroprotective effects of Rb1 were compared between conventional and PGF rats. The relative abundances of common probiotics were quantified to reveal the authentic probiotics that dominate in the neuroprotection of Rb1. The expressions of the gamma-aminobutyric acid (GABA) receptors, including GABAA receptors (α2, β2, and γ2) and GABAB receptors (1b and 2), in the normal, ischemia/reperfusion (I/R), and I/RþRb1 rat hippocampus and striatum were assessed to reveal the neuroprotective mechanism of Rb1. Results: The results showed that microbiota plays a key role in neuroprotection of Rb1. The relative abundance of Lactobacillus helveticus (Lac.H) increased 15.26 fold after pretreatment with Rb1. I/R surgery induced effects on infarct size, neurological deficit score, and proinflammatory cytokines (IL-1β, IL-6, and TNF-α) were prevented by colonizing the rat gastrointestinal tract with Lac.H (1×10<SUP>9</SUP> CFU) by gavage 15 d before I/R surgery. Both Rb1 and Lac.H upregulated expression of GABA receptors in I/R rats. Coadministration of a GABAA receptor antagonist significantly attenuated neuroprotective effects of Rb1 and Lac.H. Conclusion: In sum, Rb1 exerts neuroprotective effects by regulating Lac.H and GABA receptors rather than through direct distribution to the target sites.

Ginsenoside Rb1 exerts neuroprotective effects through regulation of Lactobacillus helveticus abundance and GABA_A receptor expression

Chen, Huimin,Shen, Jiajia,Li, Haofeng,Zheng, Xiao,Kang, Dian,Xu, Yangfan,Chen, Chong,Guo, Huimin,Xie, Lin,Wang, Guangji,Liang, Yan The Korean Society of Ginseng 2020 Journal of Ginseng Research Vol.44 No.1

Background: Ginsenoside Rb1 (Rb1), one of the most abundant protopanaxadiol-type ginsenosides, exerts excellent neuroprotective effects even though it has low intracephalic exposure. Purpose: The present study aimed to elucidate the apparent contradiction between the pharmacokinetics and pharmacodynamics of Rb1 by studying the mechanisms underlying neuroprotective effects of Rb1 based on regulation of microflora. Methods: A pseudo germ-free (PGF) rat model was established, and neuroprotective effects of Rb1 were compared between conventional and PGF rats. The relative abundances of common probiotics were quantified to reveal the authentic probiotics that dominate in the neuroprotection of Rb1. The expressions of the gamma-aminobutyric acid (GABA) receptors, including GABAA receptors (α2, β2, and γ2) and GABAB receptors (1b and 2), in the normal, ischemia/reperfusion (I/R), and I/R+Rb1 rat hippocampus and striatum were assessed to reveal the neuroprotective mechanism of Rb1. Results: The results showed that microbiota plays a key role in neuroprotection of Rb1. The relative abundance of Lactobacillus helveticus (Lac.H) increased 15.26 fold after pretreatment with Rb1. I/R surgery induced effects on infarct size, neurological deficit score, and proinflammatory cytokines (IL-1β, IL-6, and TNF-α) were prevented by colonizing the rat gastrointestinal tract with Lac.H (1 × 10⁹ CFU) by gavage 15 d before I/R surgery. Both Rb1 and Lac.H upregulated expression of GABA receptors in I/R rats. Coadministration of a GABA_A receptor antagonist significantly attenuated neuroprotective effects of Rb1 and Lac.H. Conclusion: In sum, Rb1 exerts neuroprotective effects by regulating Lac.H and GABA receptors rather than through direct distribution to the target sites.

An Electrochemical Sensor Based on Graphene-Polypyrrole Nanocomposite for the Specific Detection of Pb (II)

Rong Rong,Huimin Zhao,Xiao Rong Gan,Shuo Chen,Xie Quan 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2017 NANO Vol.12 No.1

An electrochemical sensor for the rapid, selective and sensitive detection of Pb2+ was developed using polypyrrole-graphene (PPY-rGO) nanocomposite by electrochemical synthesis. The PPYrGO-modified electrode possessed a large effective area because of unique 3D porous architectures, and it displayed excellent selectivity for the determination of Pb2+. The response of Pb2+ on the nanocomposite-modified electrode was evaluated, and the relevant parameters were optimized by square wave anodic stripping voltammetry (SWASV). The stripping response was highly linear (R2 = 0.987) over a Pb2+ concentration range of 5 X 10-9 mol/L to 7.5 X 10-7 mol/L, with a detection limit of 4.7 X 10-11 mol/L (3σ method). Furthermore, its applicability was validated for the determination of Pb2+ levels using spiked tap water at different concentrations. The polyporous structure, satisfactory reproducibility, long-term stability and simple synthesis endow the PPY-rGO nanocomposite a promising application in the determination of Pb2+.

Consensus Seeking of Multi-agent Systems from an Iterative Learning Perspective

Juntao Li,Yadi Wang,Huimin Xiao 제어·로봇·시스템학회 2016 International Journal of Control, Automation, and Vol.14 No.5

The consensus seeking problems for both discrete and continuous multi-agent networks are discussedfrom an iterative learning perspective. It is shown that the consensus seeking process can be viewed as an iterativelearning process for agents under directed networks to improve their performances from time to time in order toachieve consensus. If a desired consensus state is specified, then the multi-agent system can be guaranteed toreach consensus through reducing the tracking error between each agent’s state and the desired consensus statemonotonically to zero with respect to the increasing of time. If there is no desired consensus state, then the agentscan achieve consensus through reducing their states monotonically to the minimum quantity with increasing time. Simulations illustrate the observed results.

SOFTWARE PERFORMANCE TESTING BASED ON LINUX KERNEL

Yuan Yuan Li,Peng Xiao,Huimin Meng 한국멀티미디어학회 2006 한국멀티미디어학회 국제학술대회 Vol.2006 No.-

Linux has created a huge new playing field for enterprises, academia, and governments. But lack and instability of applications have stopped many users from strategic, wholesale migrations to Linux. With more and more applications running on Linux system, for example mozilla fire fox, openoffice, GCC, etc. the software performance testing is becoming important on Linux platform. The kernel of an operating system has a significant impact on the overall performance of a computer system [1]. To test a software performance based on system kernel can give us a unique insight into the software, provide us useful information in determining the bottlenecks and weaknesses of the software, and thus enable us to improve it. This paper discusses the methodologies of software performance testing based on Linux kernel, which include design workload, get system parameter, time measurement and CPU utilized. We have done experiments on a computer running Linux; experiment results show that the methodologies of software performance testing based on Linux kernel is completely realizable and efficacious. Even though this paper is not intended to provide a comprehensive software test suite, the methodologies presented here can be extended to build such programs.