A Green Protocol for Asymmetric Epoxidation of Olefins Catalyzed by Carbon Dioxide Soluble Chiral Salen-Mn(III) Complexes in Supercritical CO₂

Gao, Chun-Ji,Shin, Woo-Seob,Han, Jung-Min,Han, Dongg-Yun,Adharvana Chari, M.,Kim, Hong-Doo,Ahn, Kwang-Hyun Korean Chemical Society 2009 Bulletin of the Korean Chemical Society Vol.30 No.3

Fabrication of Magnetite Nanoparticle-embedded Polystyrene Composites and Their Additive Role on the Dynamic Properties of Carbonyl Iron-based Magneto-rheological Fluids

Chun Yan Gao,Qi Lu,Hyoung Jin Choi,Nam Hui Kim,Chun Yeol You 한국자기학회 2019 Journal of Magnetics Vol.24 No.1

Magnetic Fe₃O₄@polystyrene (PS) nanoscale composite particles were fabricated using a unique Shirasu porous-glass membrane technique and used as additives to a magnetorheological (MR) suspension with magnetic carbonyl-iron (CI) particles. The morphology of the fabricated Fe₃O₄@PS composites was characterized by transmission electron microscopy. The effects of the Fe₃O₄@PS composite particle additive on its MR behavior was examined using a rotation rheometer under an applied magnetic field. The results revealed improved MR behavior, such as higher storage and loss moduli, and elastic yield stress compared to those of the pure CIbased MR suspension under an external magnetic field.

Pre-operative Predictive Factors for Intra-operative Pathological Lymph Node Metastasis in Rectal Cancers

Gao, Chun,Li, Jing-Tao,Fang, Long,Wen, Si-Wei,Zhang, Lei,Zhao, Hong-Chuan Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.11

Background: A number of clinicopathologic factors have been found to be associated with pathological lymph node metastasis (pLNM) in rectal cancer; however, most of them can only be identified by expensive high resolution imaging or obtained after surgical treatment. Just like the Child-Turcotte-Pugh (CTP) and the model for end-stage liver disease (MELD) scores which have been widely used in clinical practice, our study was designed to assess the pre-operative factors which could be obtained easily to predict intra-operative pLNM in rectal cancer. Methods: A cohort of 469 patients who were treated at our hospital in the period from January 2003 to June 2011, and with a pathologically hospital discharge diagnosis of rectal cancer, were included. Clinical, laboratory and pathologic parameters were analyzed. A multivariate unconditional logistic regression model, areas under the curve (AUC), the Kaplan-Meier method (log-rank test) and the Cox regression model were used. Results: Of the 469 patients, 231 were diagnosed with pLNM (49.3%). Four variables were associated with pLNM by multivariate logistic analysis, age<60 yr (OR=1.819; 95% CI, 1.231-2.687; P=0.003), presence of abdominal pain or discomfort (OR=1.637; 95% CI, 1.052-2.547; P=0.029), absence of allergic history (OR=1.879; 95% CI, 1.041-3.392; P=0.036), and direct $bilirubin{\geq}2.60{\mu}mol/L$ (OR=1.540; 95% CI, 1.054-2.250; P=0.026). The combination of all 4 variables had the highest sensitivity (98.7%) for diagnostic performance. In addition, age<60 yr and direct $bilirubin{\geq}2.60{\mu}mol/L$ were found to be associated with prognosis. Conclusion: Age, abdominal pain or discomfort, allergic history and direct bilirubin were associated with pLNM, which may be helpful for preoperative selection.

Disambiguate Chinese Word Sense Based on Linguistics Knowledge

Chun-Xiang Zhang,Long Deng,Xue-Yao Gao,Zhi-Mao Lu 보안공학연구지원센터 2014 International Journal of Database Theory and Appli Vol.7 No.6

Word sense disambiguation (WSD) is important to many application problems in natural language processing fields, such as machine translation, parsing analysis and information retrieval. In this paper, we propose a new method to determine correct sense categories of Chinese words based on linguistics knowledge. The left word string and the right word string around the ambiguous word are respectively analyzed. Their syntactic structures are obtained for determining its intended sense. Syntactic category and part of speech are extracted as disambiguation features. A naive bayesian model is used as the classifier. Experimental results showed that the accuracy rate of classification arrives at 64%. The performance of disambiguation is improved.

Hollow submicron-sized spherical conducting polyaniline particles and their suspension rheology under applied electric fields

Gao, Chun Yan,Meng, Long-Yue,Piao, Shang Hao,Choi, Hyoung Jin Elsevier 2018 Polymer Vol.140 No.-

<P><B>Abstract</B></P> <P>Conducting polymeric polyaniline hollow spheres (PANI-HS) were fabricated and evaluated as a smart electro-stimuli responsive material, whose both special structure of shorter diffusion length promotes the electron transfer and specific surface area is greatly amplified than solid spheres. The monodisperse polystyrene (PS) seeds were initially synthesized by a facile surfactant-free emulsion polymerization, and then the monomer aniline was adsorbed and polymerized on the sulfonated PS spheres to form the PS/polyaniline (PANI) composites, allowing the PS cores to be removed by a solvent extraction later. The morphology and shell thickness were examined using both scanning electron microscopy and transmission electron microscopy. Fourier transformation infrared spectroscopy affirmed chemical structure of pure PS, PS/PANI and PANI-HS. The dielectric spectra were further analyzed for their electrorheological (ER) characteristics with LCR meter. The homogeneous semi-conducting PANI-HS based ER fluid (10 vol%) exhibited typical ER characteristics according with the conductivity model based on a slope of 1.5.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Hollow polyaniline (PANI-HS) was adopted as an electrorheological (ER) material. </LI> <LI> Its special structure of shorter diffusion length promotes electron transfer. </LI> <LI> PS cores in PS/PANI composite were removed by solvent extraction. </LI> <LI> ER fluid showed typical ER characteristics with a slope of 1.5. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Conducting polyaniline hollow submicron-sized spheres (PANI-HS) were fabricated and evaluated as a smart electro-stimuli responsive material. Polystyrene (PS) seeds were initially synthesized by a facile surfactant-free emulsion polymerization, and then the aniline was adsorbed and polymerized on the sulfonated PS spheres to form the PS/PANI composites, allowing the PS cores to be removed by a solvent extraction later. Their electrorheological behaviors of hollow PANI based ER fluid (10 vol %) were observed using a rotational rheometer at different electric field strengths, showing dramatic electro-stimuli responsive phase transition.</P> <P>[DISPLAY OMISSION]</P>

중국 도시와 농촌의 노인복지정책에 관한 비교 연구

고춘란 ( Chun Lan Gao ),김선희 ( Seon Hee Kim ) 한국가정과학회 2007 한국가정과학회지 Vol.10 No.2

Study on Metallurgically Prepared Copper-Coated Carbon Fibers Reinforced Aluminum Matrix Composites

Meilian Gao,Pingping Gao,Yu Wang,Yu Wang,Ting Lei,Chun Ouyang 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.12

Carbon materials, like carbon fiber, carbon nanotubes and graphene, were widely used as promising reinforcements tostrengthen aluminum matrix composites (AMCs). The dispersion of reinforcement in matrix and interface wettability betweenmatrix and reinforcing phase have been key factors affecting AMCs properties. In this study, electroless copper-coatedcarbon fibers reinforced aluminum (Cu-Cf/Al) composites were prepared by spark plasma sintering processing followedby heat treatment. Microstructure and mechanical properties were investigated. Microstructure observation indicated thatfibers distributed uniformly in the composites containing up to 9 wt% copper-coated carbon fibers (Cu-Cf). In addition, aninterfacial layer of 50 nm thickness was formed between the fiber and Al matrix due to mutual diffusion of Cu and Al atoms. Vickers hardness, tensile strength and bending strength of 9 wt% Cu-Cf/Al composite increased from 40 to 93 HV, 59 to190 MPa and 110 to 326 MPa, respectively, compared to Al matrix. The improved mechanical properties are ascribed to thesynergistic effect of dispersion, precipitation and solution strengthening. However, the elongation of composite decreased ascompared to that of Al matrix. Moreover, Cu-Cf/Al composite exhibits superior corrosion resistance over uncoated carbonfiber/Al composite but less than Al matrix.

중국 사회정책 발달과정에 관한 연구

高春蘭(Chun lan Gao) 사회복지정책실천회 2016 사회복지정책과 실천 Vol.2 No.2

본 연구는 중국 사회정책 발달과정을 경제체제개혁과 사회변화에 따라 계획경제시대, 전환기, 새로운 시대의 사회정책으로 구분하여 분석하였다. 각 단계에 따른 분석 내용으로는 핵심 사회정책이라 할 수 있는 사회(노동)보험제도, 취업제도, 공공부조, 주택제도 등이다. 계획경제 시대에 국가는 사회복지 제공의 유일한 주체였으며, 사회정책은 경제정책에 종속되었고 국가 재분배 제도의 일부분이었다. 비록 국가가 독자적으로 사회복지 자원을 배분하지만 복지혜택이 평등하게 분배된 것이 아니라 도시의 “단위인” 신분으로서 자격이 주어졌으며 이러한 신분은 도시 호적과 국가에서 분배한 일자리와 관련되었다. 경제체제 개혁과 더불어 사회정책은 전환기에 들어섰다. 전환기의 사회정책은 경제개혁과정에서 야기된 문제를 해결하는 도구이자 사회 안정을 유지하는 장치이다. 이 시기 중국 정부는 국유기업개혁 수요에 따라 기업 혹은 단위와 분리된 사회보장체계를 수립하였으며 사회복지의 사회화를 추진하여 시장의 역할을 강조하였다. 2003년부터 정부는 인간을 근본으로 하는 조화로운 사회건설 목표를 제시하면서 일련의 민생 관련정책을 시행하였다. 이로써 중국의 사회정책은 새로운 시대에 들어서게 되었다. 중국의 사회정책의 이러한 변화는 커다란 역사적 성과라 할 수 있지만 사회정책의 철학적 기초는 여전히 도덕적 배려의 성격에 머물러 있고 시민권적 보장으로 간주되지 않고 있다. 사회정책의 내용도 현금이나 현물지급이 주룰 이루고 있으며 사회서비스는 간과되고 있다. 일부 학자들은 멀지 않은 미래에 중국은 사회정책의 시대로 들어서게 될 것이라고 주장한다. 그러나 과학적이고 합리적이며 지속가능한 사회장책체계 구축은 아직도 여러 정책주체의 노력에 의해 보완되어야 한다. This paper is based on the economic system reform and social transformation, which divided the process of social policy development in China into three stages: the social policy in the planned economy era, the social policy in the transition period and the social policy in the new era. All stages have analyzed social (labor) insurance, employment system, social assistance, housing security and other core contents and their characteristics. In the era of planned economy, the country is the sole subject of social welfare. Economic policy and social policy were highly overlapping. Social policies depended on economic policies, and it was part of the national redistribution system. The country was trying to include everyone in the social welfare system, but not everyone enjoys the equal benefits given by the government. The qualification for obtaining access to the benefits was based on “unit person” identity. This identity was closely related with the urban household and jobs distributed by the nation. With the reformation of the economic system, social policy has entered the transition period. During this period, the government has gradually established a social security system that was independent of enterprises and public institutions, to promote social welfare socialization process and strengthen the role of the market. Since year 2003, the government has put forward the goal of putting people first and building a harmonious society. China s social policies have entered a new period of development, and a series of social policies have been adopted to improve people s livelihood. Although social policies in China have made great progress, their philosophical foundations is still in the moral level of humanitarian concern, and have not risen to the political height of civil rights. The content of social policies is mainly about economic material assistance, and the social service supply has not risen to the status that it was supposed to be. Although some Chinese scholars believe that China will soon usher in the era of social policy, to establish a scientific and rational sustainable social policy system, and the process is still difficult and will have a long way to go.

The natural product salicin alleviates osteoarthritis progression by binding to IRE1α and inhibiting endoplasmic reticulum stress through the IRE1α-IκBα-p65 signaling pathway

Zhu Zhenglin,Gao Shengqiang,Chen Cheng,Xu Wei,Xiao Pengcheng,Chen Zhiyu,Du Chengcheng,Chen Bowen,Gao Yan,Wang Chunli,Wang Chunli,Huang Wei 생화학분자생물학회 2022 Experimental and molecular medicine Vol.54 No.-

Despite the high prevalence of osteoarthritis (OA) in older populations, disease-modifying OA drugs (DMOADs) are still lacking. This study was performed to investigate the effects and mechanisms of the small molecular drug salicin (SA) on OA progression. Primary rat chondrocytes were stimulated with TNF-α and treated with or without SA. Inflammatory factors, cartilage matrix degeneration markers, and cell proliferation and apoptosis markers were detected at the mRNA and protein levels. Cell proliferation and apoptosis were evaluated by EdU assays or flow cytometric analysis. RNA sequencing, molecular docking and drug affinity-responsive target stability analyses were used to clarify the mechanisms. The rat OA model was used to evaluate the effect of intra-articular injection of SA on OA progression. We found that SA rescued TNF-α-induced degeneration of the cartilage matrix, inhibition of chondrocyte proliferation, and promotion of chondrocyte apoptosis. Mechanistically, SA directly binds to IRE1α and occupies the IRE1α phosphorylation site, preventing IRE1α phosphorylation and regulating IRE1α-mediated endoplasmic reticulum (ER) stress by IRE1α-IκBα-p65 signaling. Finally, intra-articular injection of SA-loaded lactic-co-glycolic acid (PLGA) ameliorated OA progression by inhibiting IRE1α-mediated ER stress in the OA model. In conclusion, SA alleviates OA by directly binding to the ER stress regulator IRE1α and inhibits IRE1α-mediated ER stress via IRE1α-IκBα-p65 signaling. Topical use of the small molecular drug SA shows potential to modify OA progression.

2D Geometric Constraint Optimum Solving Based on Problem Decomposition

Xue-Yao Gao,Chun-Xiang Zhang,Zhi-Mao Lu 보안공학연구지원센터 2015 International Journal of Hybrid Information Techno Vol.8 No.1

Constraint solving is widely applied to many fields including computer aided design, 2 dimension (2D) model design and computer aided manufacturing. Geometric constraint solution is a difficult problem because there are a large number of entities and related parameters in 2D sketches. In this paper, a new method which decomposes geometric constraint relations based on entity-parameter graphs is proposed for reducing the size of constraint solution. A geometric constraint problem is decomposed into many independent sub-problems. Then, particle swarm optimization algorithm is used to solve constraint equations in each sub-problem. Solutions of all sub-problems are integrated to obtain the original problem’s solution. In experiments, the proposed method is applied to HUST-CAID system. Experimental results show that the method can effectively solve 2 dimension geometric constraints.