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Magnetic activity of the spotted dwarf AP149 in the α Persei open cluster

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Research in Astronomy and Astrophysics 2010年第3期10卷 253-265页

作者： Xiang-Song Fang Sheng-hong Gu Sze-Leung Cheung ho-Keung Hui chi-Tai Kwok Kam-Cheung Leung National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China Graduate University of chinese Academy of Sciences Beijing 100049 China ho Koon Nature Education cum Astronomical Centre Sik Sik Yuen Hong Kong China hong Kong Astronomical Society Hong Kong China

The simultaneous photometric and spectroscopic observations of the spotted G dwarf AP149 in the young open cluster α Persei are analyzed here. We reconstruct the observed light curves with a two-starspot model by means of a light curve modeling technique, and find that the active regions shift oppositely along longitude on a time scale of one day. Combining with the observational data obtained by other groups, we discuss the evolution of spotted regions in the photosphere, and find that its starspots evolve not only on a short time scale but also on a long time scale. The pure chromospheric emissions for Ca IIHK and Hβ lines are derived by using the spectral subtraction technique. The variation of Ca IIHK lines＇ excess emission is spatially correlated to the starspot regions. There is no clear rotational modulation for the Hβ line＇s excess emission, probably due to the contamination of prominence emission.

关键词： stars: activity -- stars: late-type -- stars: spots -- stars: individual AP149

Selenium-enriched oolong tea(Camellia sinensis)extract exerts anti-inflammatory potential via targeting NF-κB and MAPK pathways in macrophages

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Food Science and Human Wellness 2022年第3期11卷 635-642页

作者： Qi Wang Juqing Huang Yafeng Zheng Xuefang Guan Chenchun Lai Huiying Gao chi-Tang ho Bin Lin Institute of Agricultural Engineering Fujian Academy of Agricultural SciencesFuzhou 350003China College of Food Science Fujian Agriculture and Forestry UniversityFuzhou 350002China Fujian Key Laboratory of Agricultural Product(Food)Processing Fuzhou 350003China Department of Food Science Rutgers UniversityNew BrunswickNJ 08901USA

Both tea polyphenols and selenium(Se)have been suggested to exert the health benefits via the regulatory capacities of chronic inflammation,which make Se-enriched oolong tea a promising beverage as an anti-inflammatory *** aim of this study is to investigate the anti-inflammatory effects of Se-enriched oolong tea extract(Se-TE)and underlying mechanism in lipopolysaccharide(LPS)-induced RAW264.7 ***-TE treatments(50 and 150μg/m L)significantly suppressed the over-production of nitric oxide(NO)and prostaglandin E2(PGE2)in LPS-stimulated macrophages via downregulating the expression of nitric oxide synthase(i NOS)and cyclooxygenase-2(COX-2).Moreover,Se-TEs also effectively inhibited the productions of inflammatory cytokines,such as tumor necrosis factor-α(TNF-α),interleukin-6(IL-6),and interleukin-1β(IL-1β).Furthermore,Se-TE could block mitogen-activated protein kinase(MAPK)and nuclear factor-kappa B(NF-κB)signaling pathways through the inhibition of the phosphorylation of key proteins(IκB-α,p65,p38,ERK,and JNK)and the translocation of the p65 subunit into the ***,our results indicated that Se-TE may have the potential to be used as a novel food ingredient for the development of various anti-inflammatory foods and the treatment and prevention of chronic inflammation-related diseases.

关键词： Oolong tea Selenium Anti-inflammatory NF-κB and MAPK pathways

Structure variety and its effects on biological activity of tea polysaccharides

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Food Science and Human Wellness 2022年第3期11卷 587-597页

作者： Ting Hu Peng Wu Jianfeng Zhan Weixin Wang Junfeng Shen Meiyan Wang chi-Tang ho Shiming Li Hubei Key Laboratory of Economic Forest Germplasm Improvement and Resources Comprehensive Utilization Huanggang Normal UniversityHuanggang 438000China School of Biotechnology and Food Science Tianjin University of CommerceTianjin 300134China Department of Food Science Rutgers UniversityNJ 08901USA

Tea polysaccharides(TPSs),one of the major bioactive ingredients in tea,have been widely studied due to their variety of biological activities,including antioxidant,cancer prevention,hypoglycemia,anti-fatigue,anti-coagulant,anti-obesity and immunomodulatory *** biological effectiveness of TPSs has direct relation with their structures such as monosaccharide composition,molecular weight,glycosidic linkages,conformation and others,which can be influenced by tea materials,processing methods,extraction and purification procedures among *** to the study of tea polyphenols,the exploration of TPSs in structural elucidation and biofunctionality is very *** several factors affecting the structural change of TPSs have been studied and ***,the variation of some TPS biological activity brought by the change of TPS structures has been evaluated and preliminary correlation of structure activity relationship of TPSs has been ***,this review aims to serve as a summary research report regarding the influencing factors on TPSs structures and consequential effects on the biological activities of *** hope to provide updated information and systematic references for future study and functional food development of TPSs.

关键词： Tea polysaccharides Structure variety Bioactivities Relationship Influencing factors

Simultaneous quantification of 18 bioactive constituents in Ziziphus jujuba fruits by HPLC coupled with a chemometric method

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Food Science and Human Wellness 2022年第4期11卷 771-780页

作者： Tianyi Wang Sen Guo Xiameng Ren Junfeng Du Lu Bai Xueqin Cui chi-Tang ho Naisheng Bai College of Food Science and Technology Northwest UniversityXi’an 710069China College of Chemical Engineering Northwest University229 Taibai North RoadXi’an 710069China Shaanxi Family Forestry Bureau Shaanxi Jiaxian Development and Reform and Science and Technology BureauYulin 719200China Department of Food Science Rutgers UniversityNew Brunswick 08901USA

The fruit of Ziziphus jujuba Mill., known as hongzao(or hong-Zao) in chinese and cultivated in china for more than 4 000 years, has shown to have hepatoprotective property. In previous study, we have isolated and identified 27 known compounds from Z. jujuba fruits, which demonstrated anti-tumor activity. In this study, a high-performance liquid chromatography-diode-array detection-mass spectrometry(HPLC-DAD-MS) method was successfully applied to the simultaneous characterization and quantitation of 18 constituents in 28 Z. jujuba samples, comprised of 12 cultivars from different regions in china, by comparing their HPLC retention times, MS spectra, UV spectra, and NMR data with those of reference compounds. The quantitative method was validated with excellent linearity(R^(2 )> 0.999 1), preferable intra-and inter-day precisions(RSD hod(hierarchical cluster analysis). In addition, these constituents showed protection against carbon tetrachloride(CCl_(4)) intoxicated Hep G2 cell lines by decreasing lactic dehydrogenase(LDH) levels. Results in this study illustrated that the content of all 18 compounds examined has significant difference and variation among cultivars and extracts. The proposed method can serve as a prerequisite for quality control of bioactive compounds in Z. jujuba products.

关键词： Ziziphus jujuba HPLC-DAD-MS Quantitative analysis Hierarchical cluster analysis HepG2 cells

Rapid qualitative and quantitative analysis of strong aroma base liquor based on SPME-MS combined with chemometrics

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Food Science and Human Wellness 2021年第3期10卷 362-369页

作者： Zongbao Sun Junkui Li Jianfeng Wu Xiaobo Zou chi-Tang ho Liming Liang Xiaojing Yan Xuan Zhou School of Food and Biological Engineering Jiangsu UniversityZhenjiang 212013China Department of Food Science Rutgers UniversityNew BrunswickNew Jersey 08903USA Jiangsu King’s Luck Brewery Co.Ltd. Lianshui 223411China

To objectively classify and evaluate the strong aroma base liquors(SABLs)of different grades,solid-phase microextraction-mass spectrometry(SPME-MS)combined with chemometrics were *** showed that SPME-MS combined with a back-propagation artificial neural network(BPANN)method yielded almost the same recognition performance compared to linear discriminant analysis(LDA)in distinguishing different grades of SABL,with 84%recognition rate for the test *** least squares(PLS),successive projection algorithm partial least squares(SPA-PLS)model,and competitive adaptive reweighed samplingpartial least squares(CARS-PLS)were established for the prediction of the four esters in the ***-PLS model showed a greater advantage in the quantitative analysis of ethyl acetate,ethyl butyrate,ethyl caproate,and ethyl *** results corroborated the hypothesis that SPME-MS combined with chemometrics can effectively achieve an accurate determination of different grades of SABL and prediction performance of esters.

关键词： SPME-MS Strong aroma base liquor(SABL) Chemometrics Grade identification Ester compounds

Analyses on the Ionization Instability of Non-Equilibrium Seeded Plasma in an MHD Generator

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Plasma Science and Technology 2016年第6期18卷 674-679页

作者： Le chi KIEN ho chi Minh City University of Technology and Education 01 Vo Van Ngan Thu DucHo Chi Minh City Vietnam

Recently,closed cycle magnetohydrodynamic power generation system research has been focused on improving the isentropic efficiency and the enthalpy extraction *** reducing the cross-section area ratio of the disk magnetohydrodynamic generator,it is believed that a high isentropic efficiency can be achieved with the same enthalpy *** this study,the result relating to a plasma state which takes into account the ionization instability of non-equilibrium seeded plasma is added to the theoretical prediction of the relationship between enthalpy extraction and isentropic *** a result,the electron temperature which reaches the seed complete ionization state without the growth of ionization instability can be realized at a relatively high seed fraction ***,the upper limit of the power generation performance is suggested to remain lower than the value expected in the low seed fraction *** is also suggested that a higher power generation performance may be obtained by implementing the electron temperature range which reaches the seed complete ionization state at a low seed fraction.

关键词： isentropic efficiency enthalpy extraction ionization instability seed fraction

Phytochemical Analysis of Ziziphus jujuba Leaves in Six Cultivars at the Whole Life Stage by High Performance Liquid Chromatography

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Chemical Research in chinese Universities 2017年第5期33卷 702-708页

作者： CUI Xueqin MA Zhongxiao BAI Lu WU Yong GUO Sen LIU Qingchao ZHANG Li ho chi-Tang BAI Naisheng College of Chemical Engineering Department of Pharmaceutical Engineering Northwest University Xi'an 710069 P. R. China Department of Food Science Rutgers University New Brunswick New Jersey 08901 USA

Leaves of Ziziphus jujuba Mill.（Z. jujuba） were used as a folk medicine to treat children suffering from typhoid fever, furuncle and ecthyma in china. The present study was to establish a high performance liquid chroma- tography-diode array detector（HPLC-DAD） method for quality control of Z. jujuba leaves. The validated method was applied to the simultaneous characterization and quantification of sixteen main constituents in thirty samples, which comprised the whole life stage of Z. ]ujuba leaves from six cultivars in Yulin, Shannxi Province, china. HPLC fin- gerprint file of Z. jujuba leaves was set up and the results indicate that the major constituents of Z. jujuba leaves are （-）-catechin（1）, quercetin-3-O-robinobioside（3）, rutin（4） and quercetin-3-O-a-L-arabinosyl-（1---~2）-a-L-rhamnoside（6） with the total contents of the nine flavonoids in respective batch ranging from 18.52 mg/g to 39.51 mg/g. In addition, the contents of compounds depend on both the season and the cultivar. During ripening of Z. jujuba leaves, flavo- noids of all the cultivars present a similar trend： initially decrease from 25th, Jun. to 5th, Aug., 2015, and then in- crease for a period of time, finally slightly fluctuate on 5th Oct. The highest contents of total flavonoids were regis- tered on 25th Jun., 2015. Different cultivars have 50%--90% variation on the content for the three classes of com- pounds. Taken together, the results demonstrate that Z. jujuba leaves have great potential to be a new health-promoting resource based on flavonoids and the best sampling time of them is in June.

关键词： Flavonoid High performance liquid chromatography-diode array detector(HPLC-DAD) Quality control Ziziphus jujuba leaf

What do we know about housing supply?The case of hong Kong SAR

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Economic and Political Studies 2020年第1期8卷 6-20页

作者： Charles Ka Yui Leung Joe Cho Yiu Ng Edward chi ho Tang Department of Economics and Finance City University of Hong KongHong Kong SARChina Department of Economics and Finance Hong Kong Shue Yan UniversityHong Kong SARChina

The house price in the hong Kong SAR of china is well-known to be‘unaffordable’.This paper relates the macroeconomy with the housing market of hong Kong and argues that the housing supply plays a vital role in explaining the *** paper also shows that there are some practical challenges in understanding the housing supply of hong Kong,including the potentially complicated ownership structure of real estate *** the discussion centres on the situation of hong Kong,its lesson may also apply to housing markets in other small open economies.

关键词： New housing supply oligopolistic market structure ownership structure real estate development real estate developers

Percutaneous transcatheter closure of mitral paravalvular leak via transarterial retrograde approach

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Journal of Geriatric Cardiology 2015年第6期12卷 683-686页

作者： ho-Ping Yu chi-Hung Huang Shaw-Min hou Ming-Chon Hsiung Shen-Kou Tsai Wei-Hsian Yin Heart Center Cheng-Hsin General Hospital Taipei Taiwan China Division of Cardiology Cathay General Hospital Taipei Taiwan China Division of Cardiac Surgery Cathay General Hospital Taipei Taiwan China Department of Anesthesiology Cheng-Hsin General Hospital Taipei Taiwan China Faculty of Medicine School of Medicine National Yang Ming University Taipei Taiwan China

Repeat surgery has usually been considered the first choice to solve paravalvular leaks of prosthetic valves, but it cames a high operative risk, a high mortality rate and an increased risk for re-leaks. Percutaneous closure of such defects is possible, and different approaches and devices are used for this purpose. For mitral paravalvular leaks, constructing an arterio-venous wire loop for delivering the closure device through an antegrade approach is the most commonly used technique. Transcatheter closure can also be performed through a transapical approach or retrograde transfemoral arterial approach. We present a case of 68-year-old man with a mitral paravalvular leak that was suc- cessfully closed using an Amplatzer~ Duct Occluder H, via retrograde transfemoral arterial approach under three-dimensional transesophag- eal echocardiographic guidance, without the use of a wire loop. The initial attempt to cross the paravalvular defect was unsuccessful, but the obstacle was finally overcome by introducing complex interventional techniques.

关键词： Antegrade approach Paravalvular leaks Prosthetic valve Retrograde approach Wire loop