• Title/Summary/Keyword: Chinese L1

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Ophiopojaponin D, a New Phenylpropanoid Glycoside from Ophiopogon japonicus Ker-Gawl

  • Dai Hao Fu;Mei Wen Li
    • Archives of Pharmacal Research
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    • v.28 no.11
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    • pp.1236-1238
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    • 2005
  • A new phenolic glycoside, ophiopojaponin D (1), together with two known compounds, was isolated from the tubers of a famous traditional Chinese herb-Ophiopogon japonicus Ker-Gawl. The spectroscopic and chemical data revealed their structures to be 3-tetradecyloxy-4­hydroxy-allylbenzene-4-O-$\alpha$-L-rhamnopyranosyl (1$\rightarrow$6)-$\beta$-D-glucopyranoside (1), 3, 4-dihy-droxy-allylbenzene-4-O-$\alpha$-L-rhamnopyranosyl (1$\rightarrow$6)-$\beta$-D-glucopyranoside (2) and L-pyro­glutamic acid (3).

Dynamic Studies on Physiology and Biochemistry in American Ginseng Seed During Stratification - Part II. Contents of Soluble Carbohydrate, Crude Fat, Fatty Acid and Soluble Protein - (충적과정중 미국인삼 종자의 생리 및 생화학적 지표에 관한 동태학적 연구 I)

  • Huang, Yao-Ge;Li, Xiang-Gao;Cui, Shu-Yu;Yu, Wen-Bo;Kuang, Ya-Lan;Yan, Jie-kun;Yang, Ji-Xiang;Liu, Ren-Song;Kim, Hack-Seang
    • Journal of Ginseng Research
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    • v.21 no.1
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    • pp.39-42
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    • 1997
  • Dynamic parameters of biochemistry including the contents of soluble carbohydrate (SC) , crude fat (CF) , fatty arid (FA) and soluble protein (SP) in American send (Panax qufnquelolium L.) seed are reported in the present paper. When embryo ratio (ER) increased from 7.31 to 20.48%, the SC content decreased from 4.08 to 1.16%. After that, SC content changed little. The CF content decreased successively from 34.50 to 14.40% from the beginning to the end during the embryo afterripening. The changes of FA content did not correlate with that of ER and the changing range of SP content was not large during the seed stratification. All of these may provide some information for understanding the dormancy mechanisms of American seng seed.

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Synthesis of (5R,8R)-2-(3,8-Dimethyl-2-oxo-1,2,4,5,6,7,8,8α-octahydroazulen-5-yl) Acrylic Acid (Rupestonic Acid) Amide Derivatives and in vitro Inhibitive Activities against Influenza A3,B and Herpes Simplex Type 1 and 2 Virus

  • Yong, Jian-Ping;Lv, Qiao-Ying;Aisa, Haji Akber
    • Bulletin of the Korean Chemical Society
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    • v.30 no.2
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    • pp.435-440
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    • 2009
  • 19 Aromatic ring and L-amino acid ester contained rupestonic acid amide derivatives 2a~2l, 3a~3g were synthesized and preliminarily evaluated in vitro against influenza virus $A_3$,B and herpes simplex virus type 1 (HSV-1), 2(HSV-2) by the national center for drug screening of China. The rusults showed that 2i possessed the highest inhibition against both influenza virus $A_3\;(TC_{50}\;=\;120.6\;{\mu}mol/L,\;IC_{50}=\;19.2\;{\mu}$mol/L, SI = 6.3) and B (T$C_{50}\;=\;120.6\;{\mu}mol/L,\;IC_{50}=\;29.9\;{\mu}$mol/L, SI = 4.0); 2g was more active against influenza $A_3$ virus at very low cytotoxicity ($TC_{50}\;>\;2092.1\;{\mu}mol/L,\;IC_{50}=\;143.7\;{\mu}mol/L,$ SI > 14.6) than the parent compound; Compounds 2b, 2c, 2f showed higher activities both against HSV-1 and HSV-2 than that of the parent compound, and 2f was the most potent inhibitor of HSV-1 ($TC_{50}\;=\;200.0\;{\mu}mol/L,\;IC_{50}\;=\;11.3\;{\mu}mol$/L, SI = 17.7 ) and HSV-2 ($TC_{50}\;=\;200.0\;{\mu}mol/L,\;IC_{50}\;=\;20.7\;{\mu}mol$/L , SI = 9.7).

Differential role of endothelium in hawthorn fruit extract-induced relaxation of rat cerebral, coronary, carotid, and aorta

  • Chan, Hoi Yun;Chen, Zhen-Yu;Yao, Xiaoqiang;Lau, Chi-Wai;Zhang, ZeSeng;Ho, Walter Kwok Keung;Huang, Yu
    • Advances in Traditional Medicine
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    • v.2 no.2
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    • pp.87-93
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    • 2002
  • The present study was aimed to examine the role of endothelium in the relaxant effect of hawthorn fruit extract of Crataegus pinnatifida in four different types of rat arteries, posterior cerebral communicating artery, right descending coronary artery, common carotid artery, and aorta. In $9,11-dideoxy-11{\alpha}$, $9{\alpha}-epoxy-methanoprostaglandin$ $F_{2{\alpha}}$ (U46619)-preconstricted arterial rings except for aorta, the extract produced endothelium-independent relaxations with similar potency. This relaxation was unaffected by pretreatment with $100\;{\mu}M\;N^G-nitro-L-arginine$ methylester (L-NAME, the nitric oxide synthase inhibitor), $3\;{\mu}M$ 1H-[l,2,4]oxadiazolo$[4,2-{\alpha}]$quinoxalin-1-one (ODQ, the guanylate cyclase inhibitor), or $10\;{\mu}M$ indomethacin (the cyclooxygenase inhibitor). Putative $K^+$ channel blockers (charybdotoxin plus apamin or glibenclamide) did not affect the extract-induced relaxation in cerebral or coronary artery rings. In contrast, in rat aortic rings the extract produced significantly smaller relaxant response in endothelium-denuded rings than that in endothelium-intact rings. Pretreatment with L-NAME or ODQ abolished the extractinduced endothelium-dependent aortic relaxation, whilst indomethacin $(3\;{\mu}M)$ had no effect. The present results indicate that hawthorn fruit extract possesses a vasorelaxing effect in cerebral, coronary and carotid arteries and this effect is independent of the presence of a functional endothelium. However, the extract-induced endothelium-dependent relaxation in rat aorta was mediated through endothelial nitric oxide and cyclic GMP-dependent mechanisms, suggesting that active components in the extract may act on endothelium to stimulate release of nitric oxide in large conduit arteries of the rats.

Effects of a variety of treatments affecting Chinese cabbage protoplast culture, and plant regeneration from protoplast-derived callus (배추 원형질체 배양에 미치는 다양한 처리의 효과와 원형질체 유래 캘러스로부터 신초 재분화)

  • Han, Jeung-Sul;Yoon, Moo-Kyeong;Jeong, Mi-Hye
    • Journal of Plant Biotechnology
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    • v.35 no.3
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    • pp.235-243
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    • 2008
  • Here we describe a procedure for Chinese cabbage protoplast culture and effects of various treatments. Chinese cabbage protoplasts were isolated from different parts of young seedlings as using an enzyme mixture, of which yield was maximized in seven hours around after digestion. The highest rate of initial cell division followed by micro-callus formation was obtained in the medium with 1.0 mg/L 2,4-D, 0.5 mg/L NAA, and 1.0 mg/L BA when the cotyledon-derived protoplasts were cultured. Initiation of cell division and micro-callus proliferation significantly depended upon Chinese cabbage genotype under a same culture circumstances. The micro-calli developed from cotyledon tissue of Norang-Bom cultivar successfully grew toward callus colonies on the solidified medium with 0.2 mg/L zeatin and 0.1 mM spermidine. The callus colonies generated de novo shoots at the maximum frequency of 4.3% on the medium with 5.0 mg/L BA and 1.0 mg/L NM. Our results might be helpful for further studies to enhance the regeneration efficiency in Chinese cabbage protoplast culture.

A Study on the Length and Formant Structures of the Korean Liquid 'ㄹ' Pronounced by Chinese Learners and Koreans (중국인 한국어 학습자와 한국인의 'ㄹ' 발음의 길이와 포먼트에 대한 연구)

  • Fan Liu
    • MALSORI
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    • no.57
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    • pp.43-58
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    • 2006
  • This study aims to investigate whether Chinese learning Korean and Korean native speakers show any difference in length and formant structures of the Korean liquid 'ㄹ' in the environments of v_v and v_# through the acoustic analysis of 10 Chinese learners' and 10 Koreans' utterances. The acoustic analysis of L2KSC DB shows that the length and formant structures of 'ㄹ' produced by Chinese learners are significantly different from the ones by Koreans. I explain these differences by contrasting the liquids and syllable structure constraints of the two languages, Chinese and Korean. In addition, I relate the F1 and F2's values to the tongue's movement when making a constriction, and conclude that Chinese learners pronounce the 'ㄹ' in the v_# environment with the tongue lower and backer than Koreans do.

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Development of Techniques for the Production of Selenium and Germanium-enriched Chinese Cabbage and Pepper (셀레늄과 게르마늄 강화 배추와 고추 생산기술)

  • Yun, Hyung-Kwon;Zhang, Cheng-Hao;Seo, Tae-Cheol;Huang, Hua-Zi
    • Journal of Bio-Environment Control
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    • v.16 no.3
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    • pp.180-185
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    • 2007
  • The effects of selenium (Se) and germanium (Ge) fertilization on the growth and quality of Chinese cabbages cultivated in spring and autumn and peppers cultivated in spring were investigated. $Se\;(Na_2SeO_4)\;and\;Ge\;(GeO_2)$ were supplied 5, 10, or 20 times in an aqueous solution of 0, 2, 4, or $8mg{\cdot}L^{-1}$ during the cultivation of Chinese cabbages and peppers. The fresh weight of Chinese cabbages increased by Ge fertilization with high concentration. But it was not affected by Se fertilization. The content of vitamin C increased by 10 times application with $4mg{\cdot}L^{-1}$ of Se or Ge. The concentration of Se in Chinese cabbage increased according to increasing concentration of Se fertilization. Se concentration was higher in the outer leaves than in the inner leaves. Se concentration in the mesophyll was higher than that in the midrib. Ge fertilization increased the uptake and concentration of Ge in autumn-cultivated Chinese cabbages. Se and Ge fertilization did not affect the fresh weight of peppers. The content of vitamin C in pepper increased by 20 times application of $2mg{\cdot}L^{-1}$ of Se. Vitamin C content in red peppers was twice as much as in green peppers.

Perception and production of English fricatives by Chinese learners of English: Error patterns and perception-production relationship

  • Zhang, Buyi;Zhang, Jiaqi;Lee, Sook-hyang
    • Phonetics and Speech Sciences
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    • v.13 no.1
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    • pp.25-36
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    • 2021
  • This study examined the perception and production of eight English fricatives /f/, /v/, /θ/, /ð/, /s/, /z/, /ʃ/, and /ʒ/ by thirty Chinese English majors and thirty Chinese middle school students through a fricative identification test, an intelligibility test, and a goodness rating test and focused on error patterns and the perception-production relationship. The results showed that substitution errors occurred frequently in the perception and production of English fricatives by both the English majors and the middle school students. Further, the error patterns were attributed to various influencing factors such as the negative transfer from Chinese consonant inventory, hypercorrection or overcompensation mistakes, deficiency of L2 teaching, and acoustic similarities. Significant overall correlations were found between the fricative perception and production by the two subject groups but were not manifested in all the eight fricatives, indicating that Chinese learners' perceptual competence of target fricatives was not necessarily tied to their productive excellence of those sounds in all cases. Furthermore, precedences of perception over production were incompletely manifested in the eight fricatives, which suggested that perception might not always be a necessary prerequisite for production. Additionally, subject group and vowel context differences were observed. The English majors performed better than the middle school students, both perceptually and productively, and the subjects' performances in perception and production varied when vowel contexts changed.

Active control of amplitude and phase of high-power RF systems in EAST ICRF heating experiments

  • Guanghui Zhu;Lunan Liu;Yuzhou Mao;Xinjun Zhang;Yaoyao Guo;Lin Ai;Runhao Jiang;Chengming Qin;Wei Zhang;Hua Yang;Shuai Yuan;Lei Wang;Songqing Ju;Yongsheng Wang;Xuan Sun;Zhida Yang;Jinxin Wang;Yan Cheng;Hang Li;Jingting Luo
    • Nuclear Engineering and Technology
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    • v.55 no.2
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    • pp.595-602
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    • 2023
  • The EAST ICRF system operating space has been extended in power and phase control with a low-level RF system for the new double-strap antenna. Then the multi-step power and periodic phase scanning experiment were conducted in L-mode plasma, respectively. In the power scanning experiment, the stored energy, radiation power, plasma impedance and the antenna's temperature all have positive responses during the short ramp-ups of PL;ICRF. The core ion temperature increased from 1 keV to 1.5 keV and the core heating area expanded from |Z| ≤ 5 cm to |Z| ≤ 10 cm during the injection of ICRF waves. In the phasing scanning experiment, in addition to the same conclusions as the previous relatively phasing scanning experiment, the superposition effect of the fluctuation of stored energy, radiation power and neutron yield caused by phasing change with dual antenna, resulting in the amplitude and phase shift, was also observed. The active control of RF output facilitates the precise control of plasma profiles and greatly benefits future experimental exploration.

Acquisition of English speech rhythm by Chinese learners of English at different English proficiency levels

  • Zhang, Jiaqi;Lee, Sook-hyang
    • Phonetics and Speech Sciences
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    • v.11 no.4
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    • pp.71-79
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    • 2019
  • This study aims to investigate the rhythmic patterns in the English speech produced by Chinese learners of English who learn English as a foreign language (EFL learners). Utilizing interval-based rhythm metrics, namely, VarcoC, VarcoV, nPVI-C, nPVI-V, and %V, the study compared the rhythmic differences in English speech between ten native speakers from the United States and forty Chinese EFL learners from mainland China. A sentence elicitation task consisting of thirty picture prompts and corresponding thirty stimuli sentences with at least five vocalic and four consonantal intervals was conducted. Statistical results reveal that both Chinese advanced learners and beginners had significantly lower degree of stress-timed in their English speech, indicating that the acquisition of the L2 speech rhythm was influenced by the learners' L1 rhythmic pattern. In addition, the results also show that the Chinese advanced learners had significantly higher degree of stress-timed in their English speech than beginners and showed no significant difference with native speakers in VarcoC and nPVI-C. These results indicate that the direction of L2 speech rhythm development was from more syllable-timed to more stress-timed.