중국전통시대 민법상의 논쟁점

張國華 慶北大學校 法學硏究所 1998 법학논고 Vol.14 No.-

In Vitro Screening for Compounds Derived from Traditional Chinese Medicines with Antiviral Activities Against Porcine Reproductive and Respiratory Syndrome Virus

( Jia Cheng ),( Na Sun ),( Xin Zhao ),( Li Niu ),( Mei Qin Song ),( Yao Gui Sun ),( Jun Bing Jiang ),( Jian Hua Guo2 ),( Yuan Sheng Bai ),( Jun Ping He ),( Hong Quan Li ) 한국미생물 · 생명공학회 2013 Journal of microbiology and biotechnology Vol.23 No.8

Seventeen compounds derived from traditional Chinese medicines (TCMs) were tested for their antiviral activity against porcine reproductive and respiratory syndrome virus (PRRSV) in vitro. Visualization with the cytopathologic effect (CPE) assay and the 3-(4, 5-dimethyithiazol- 2-yl)-2,5-diphenyltetrazolium bromide test were used to determine the 50% cytotoxic concentration (CC50) and 50% effective concentration (EC50) in cultured Marc-145 cells. Among the tested compounds, chlorogenic acid and scutellarin showed potential anti-PRRSV activity. The EC50 values were 270.8 ± 14.6 μg/ml and 28.21 ± 26.0 μg/ml and the selectivity indexes were >5.54 and 35.5, respectively. The time-of-addition and virucidal assay indicated that the anti-PRRSV activity of the two compounds could be due to their inhibiting the early stage of virus replication and/or inactivating the virus directly. The inhibition of the virus attachment was not observed in the adsorption inhibition assay. The inhibition ratios of chlorogenic acid and scutellarin were, respectively, 90.8% and 61.1% at the maximum non-cytotoxic concentrations. The results have provided a basis for further exploration of their antiviral properties and mechanisms in vivo. We believe that the chlorogenic acid and scutellarin have a great potential to be developed as new anti-PRRSV drugs for clinical application.

Separation of arenols from a low-temperature coal tar by liquid-liquid extraction

Hua-Shuai Gao,Zhi-Min Zong,Zheng Yang,Dao-Guang Teng,Xiu-Hua Sun,Li Yan,Xian-Yong Wei,Qing-Jie Guo,Tian-Sheng Zhao,Hong-Cun Bai 한국화학공학회 2020 Korean Journal of Chemical Engineering Vol.37 No.5

Low-temperature coal tar (LTCT) is a sticky liquid mixture produced mainly from coal pyrolysis, which contains various value-added chemicals (VACs). Liquid-liquid extraction is considered as one of the green and effective ways to explore the organic composition and separate the VACs from LTCT. Herein, petroleum ether, methanol, and carbon disulfide were used to extract arenols from a LTCT. As a result, the relative content and absolute content of arenols extracted from the LTCT are ca. 96.3% and 85.9%, respectively. Among them, p-cresol is predominant, accounting for 22.2%. The isolated contents of arenols are up to 84.6%. Moreover, a kilogram-scale operation was carried out under the same conditions, which offers a potential application in industrial production.

Investigation of plasma electrolytic oxidation process on AZ91D magnesium alloy

Guo-Hua Lv,Huan Chen,Li Li,Er-Wu Niu,Huan Pang,Bin Zou,Si-Ze Yang 한국물리학회 2009 Current Applied Physics Vol.9 No.1

Ceramic coatings oxidized for different time periods were prepared to characterize the plasma electrolytic oxidation (PEO) process of AZ91D magnesium alloy. The coatings were analyzed using scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscope and potentiodynamic polarization measurement. The results show that the PEO coatings perform different growth behaviors at different PEO stages, and different morphologies are exhibited on α- and β-phase of Mg substrate. The corrosion resistance measurement predicates that within the first 30 min oxidation, coating oxidized for 20 min is the best corrosion resistant. Ceramic coatings oxidized for different time periods were prepared to characterize the plasma electrolytic oxidation (PEO) process of AZ91D magnesium alloy. The coatings were analyzed using scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscope and potentiodynamic polarization measurement. The results show that the PEO coatings perform different growth behaviors at different PEO stages, and different morphologies are exhibited on α- and β-phase of Mg substrate. The corrosion resistance measurement predicates that within the first 30 min oxidation, coating oxidized for 20 min is the best corrosion resistant.

Effects of graphite additives in electrolytes on the microstructure and corrosion resistance of Alumina PEO coatings

Guo-Hua Lv,Huan Chen,Wei-Chao Gu,Wen-Ran Feng,Li Li,Er-Wu Niu,Xian-Hui Zhang,Si-Ze Yang 한국물리학회 2009 Current Applied Physics Vol.9 No.3

In the present work, graphite grains of different sizes were added into the electrolyte to prepare ceramic coatings on aluminum by plasma electrolytic oxidation (PEO). Scanning electron microscopy (SEM) coupled with an energy dispersive X-ray analysis system (EDX), Raman spectroscopy and X-ray diffractometer (XRD) were used to characterize the coatings. A three-electrode system was used to evaluate the corrosion performances of the coatings in a 3.5 wt.% NaCl solution. It was found that the morphology and corrosion performance of the coatings were significantly influenced by the size of the graphite grains. Compared with bigger graphite grains, finer ones were involved in the oxidation process and embedded within the ceramic coatings, which made the coatings less porous and more compact. Thus, the corrosion resistance of the coatings with embedded graphite grains was greatly improved. In the present work, graphite grains of different sizes were added into the electrolyte to prepare ceramic coatings on aluminum by plasma electrolytic oxidation (PEO). Scanning electron microscopy (SEM) coupled with an energy dispersive X-ray analysis system (EDX), Raman spectroscopy and X-ray diffractometer (XRD) were used to characterize the coatings. A three-electrode system was used to evaluate the corrosion performances of the coatings in a 3.5 wt.% NaCl solution. It was found that the morphology and corrosion performance of the coatings were significantly influenced by the size of the graphite grains. Compared with bigger graphite grains, finer ones were involved in the oxidation process and embedded within the ceramic coatings, which made the coatings less porous and more compact. Thus, the corrosion resistance of the coatings with embedded graphite grains was greatly improved.

A Characteristic Analysis and Countermeasure Study of the Hedging of Listed Companies in China Stock Markets

Guo-Hua WU,Xiao-Ling JIANG,Su-Ya DENG 한국유통과학회 2021 The Journal of Asian Finance, Economics and Busine Vol.8 No.10

Due to COVID-19, the risk of price volatility in commodity and equity markets increases. The research and application of hedging is the most effective way to reduce the market risk. Hedging is a risk management strategy employed to offset losses in investments by taking an opposite position in a related asset. We use K-means and hierarchical clustering methods to cluster companies and futures products respectively, and analyze the relationship between the number of hedging firms, regional distribution, nature of firms, capital distribution, company size, profitability, number of local Futures Commission Merchants (FCMs), regional location, and listing time. The study shows that listed companies with large scale and good profitability invest more money in hedging, while state-owned enterprises’ participation in hedging is more likely to be affected by the company size and the number of local futures commission merchants, and private enterprises are more likely to be affected by the company profitability and the regional location. Listed companies are more willing to choose long-listed and mature futures products for hedging. We also provide policy advice based on our conclusion. So far, there is no study on the characteristics of hedging. This paper fills the gap. The results provide a basis and guidance for people’s investment and risk management. Using clustering analysis in hedging study is another innovation of this paper.

Two-Step Oxidation of Refractory Gold Concentrates with Different Microbial Communities^s

( Guo-hua Wang ),( Jian-ping Xie ),( Shou-peng Li ),( Yu-jie Guo ),( Ying Pan ),( Haiyan Wu ),( Xin-xing Liu ) 한국미생물 · 생명공학회 2016 Journal of microbiology and biotechnology Vol.26 No.11

Bio-oxidation is an effective technology for treatment of refractory gold concentrates. However, the unsatisfactory oxidation rate and long residence time, which cause a lower cyanide leaching rate and gold recovery, are key factors that restrict the application of traditional bio-oxidation technology. In this study, the oxidation rate of refractory gold concentrates and the adaption of microorganisms were analyzed to evaluate a newly developed two-step pretreatment process, which includes a high temperature chemical oxidation step and a subsequent bio-oxidation step. The oxidation rate and recovery rate of gold were improved significantly after the two-step process. The results showed that the highest oxidation rate of sulfide sulfur could reach to 99.01 % with an extreme thermophile microbial community when the pulp density was 5%. Accordingly, the recovery rate of gold was elevated to 92.51%. Meanwhile, the results revealed that moderate thermophiles performed better than acidophilic mesophiles and extreme thermophiles, whose oxidation rates declined drastically when the pulp density was increased to 10% and 15%. The oxidation rates of sulfide sulfur with moderate thermophiles were 93.94% and 65.73% when the pulp density was increased to 10% and 15%, respectively. All these results indicated that the twostep pretreatment increased the oxidation rate of refractory gold concentrates and is a potential technology to pretreat the refractory sample. Meanwhile, owing to the sensitivity of the microbial community under different pulp density levels, the optimization of microbial community in bio-oxidation is necessary in industry.

Antioxidant Action of a Chrysanthemum morifolium Extract Protects Rat Brain Against Ischemia and Reperfusion Injury

Guo-Hua Lin,Lin Lin,Hua-Wei Liang,Xin Ma,Jing-Ye Wang,Li-Ping Wu,Hui-Di Jiang,Iain C. Bruce,Qiang Xia 한국식품영양과학회 2010 Journal of medicinal food Vol.13 No.2

The present study evaluated the potential neuroprotective effect and underlying mechanism of the total flavones extracted from Chrysanthemum morifolium (TFCM) against ischemia/reperfusion (I/R) injury. An animal model of cerebral ischemia was established by occluding the right middle cerebral artery for 90 minutes followed by reperfusion for 22 hours. The neurobehavioral scores, infarct area, and hemispheric edema were evaluated. The superoxide dismutase (SOD) activity, malondialdehyde (MDA) content, and reactive oxygen species (ROS) level in brain were also measured. The results showed that pretreatment with TFCM significantly decreased the neurological deficit scores, percentage of infarction, and brain edema and attenuated the decrease in SOD activity, the elevation of MDA content, and the generation of ROS. In isolated brain mitochondria, Ca2+-induced swelling was attenuated by pretreatment with TFCM, and this effect was antagonized by atractyloside. These results showed that pretreatment with TFCM provides significant protection against cerebral I/R injury in rats by, at least in part, its antioxidant action and consequent inhibition of mitochondrial swelling.

Dioxygen Activation and O-O Bond Formation Reactions by Manganese Corroles

Guo, Mian,Lee, Yong-Min,Gupta, Ranjana,Seo, Mi Sook,Ohta, Takehiro,Wang, Hua-Hua,Liu, Hai-Yang,Dhuri, Sunder N.,Sarangi, Ritimukta,Fukuzumi, Shunichi,Nam, Wonwoo American Chemical Society 2017 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.139 No.44

<P>Activation of dioxygen (O-2) in enzymatic and biomimetic reactions has been intensively investigated over the past several decades. More recently, O-O bond formation, which is the reverse of the O-2-activation reaction, has been the focus of current research. Herein, we report the O-2-activation and O-O bond formation reactions by manganese corrole complexes. In the O-2-activation reaction, Mn(V)-oxo and Mn(IV)-peroxo intermediates were formed when Mn(III) corroles were exposed to O-2 in the presence of base (e.g., OH-) and hydrogen atom (H atom) donor (e.g., THE or cyclic olefins); the O-2-activation reaction did not occur in the absence of base and H atom donor. Moreover, formation of the Mn(V)-oxo and Mn(IV)-peroxo species was dependent on the amounts of base present in the reaction solution. The role of the base was proposed to lower the oxidation potential of the Mn(III) corroles, thereby facilitating the binding of O-2 and forming a Mn(IV)-superoxo species. The putative Mn(IV)-superoxo species was then converted to the corresponding Mn(IV)-hydroperoxo species by abstracting a H atom from H atom donor, followed by the O-O bond cleavage of the putative Mn(IV)-hydroperoxo species to form a Mn(V)-oxo species. We have also shown that addition of hydroxide ion to the Mn(V)-oxo species afforded the Mn(IV)-peroxo species via O-O bond formation and the resulting Mn(IV)-peroxo species reverted to the Mn(V)-oxo species upon addition of proton, indicating that the O-O bond formation and cleavage reactions between the Mn(V)-oxo and Mn(IV)-peroxo complexes are reversible. The present study reports the first example of using the same manganese complex in both O-2-activation and O-O bond formation reactions.</P>

HCV-Specific Interleukin-21+CD4+ T Cells Responses Associated with Viral Control through the Modulation of HCV-Specific CD8+ T Cells Function in Chronic Hepatitis C Patients

Guo-Hua Feng,Fu-Sheng Wang,Ji-Yuan Zhang,Qing-Lei Zeng,Lei Jin,Junliang Fu,Bin Yang,Ying Sun,Tianjun Jiang,Xiangsheng Xu,Zheng Zhang,Jinhong Yuan,Liyuan Wu 한국분자세포생물학회 2013 Molecules and cells Vol.36 No.4

Interleukin-21 (IL-21)+CD4+ T cells are involved in the immune response against hepatitis B virus (HBV) by secreting IL-21. However, the role of IL-21+CD4+ T cells in the immune response against chronic hepatitis C (CHC) virus infection is poorly understood. This study aimed to investigate the role of IL-21+CD4+ T cells in CHC patients and the potential mechanisms. The study subjects in-cluded nineteen CHC patients who were grouped by viral load (low, < 106 RNA copies/ml, n = 8; high, > 106 RNA copies/ml, n = 11). The peripheral frequency of HCV-specific IL-21+CD4+ T cells was higher in the low viral load group and was negatively correlated with the serum HCV RNA viral load in all CHC patients. Meanwhile, IL-21+ cells accumulated in the liver in the low viral load group. In vitro, IL-21 treatment increased the expression of proliferation markers and cytolytic molecules on HCV-specific CD8+ T cells. In summary, these findings suggest that HCV-specific IL-21+CD4+ T cells might contribute to HCV control by rescuing HCV-specific CD8+ T cells in CHC patients.