• 제목/요약/키워드: Research laboratory

검색결과 16,299건 처리시간 0.042초

Piperoctadecalindine, a New Piperidine Alkaloid from Piper retrofractum Fruits

  • Ahn Jong Woong;Lee Chong Ock;Kim Eun Joo;Zee Ok Pyo;Kim Hyung Jin
    • Bulletin of the Korean Chemical Society
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    • 제13권4호
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    • pp.388-391
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    • 1992
  • A chemical investigation of the fruits of Piper retrofractum (Piperaceae) has led to the isolation and characterization of a novel piperidine alkaloid, piperoctadecalidine together with three known alkaloids piperine, pipernonaline and guineensine. The structure of the new compound was detemined to be (2E,4E,14Z)-N-(2,4,14-Octadecatrienoyl) piperidine by spectral and synthetic methods.

Low-Noise MEMS Microphone Readout Integrated Circuit Using Positive Feedback Signal Amplification

  • Kim, Yi-Gyeong;Cho, Min-Hyung;Lee, Jaewoo;Jeon, Young-Deuk;Roh, Tae Moon;Lyuh, Chun-Gi;Yang, Woo Seok;Kwon, Jong-Kee
    • ETRI Journal
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    • 제38권2호
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    • pp.235-243
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    • 2016
  • A low-noise readout integrated circuit (ROIC) for a microelectromechanical systems (MEMS) microphone is presented in this paper. A positive feedback signal amplification technique is applied at the front-end of the ROIC to minimize the effect of the output buffer noise. A feedback scheme in the source follower prevents degradation of the noise performance caused by both the noise of the input reference current and the noise of the power supply. A voltage booster adopts noise filters to cut out the noise of the sensor bias voltage. The prototype ROIC achieves an input referred noise (A-weighted) of -114.2 dBV over an audio bandwidth of 20 Hz to 20 kHz with a $136{\mu}A$ current consumption. The chip is occupied with an active area of $0.35mm^2$ and a chip area of $0.54mm^2$.

Heterologous Expression and Characterization of a Laccase from Laccaria bicolor in Pichia pastoris and Arabidopsis thaliana

  • Wang, Bo;Yan, Ying;Xu, Jing;Fu, Xiaoyan;Han, Hongjuan;Gao, Jianjie;Li, Zhenjun;Wang, Lijuan;Tian, Yongsheng;Peng, Rihe;Yao, Quanhong
    • Journal of Microbiology and Biotechnology
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    • 제28권12호
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    • pp.2057-2063
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    • 2018
  • Laccases can oxidize a variety of phenolic and non-phenolic substrates including synthetic dyes. In this research, a laccase gene Lcc9 from Laccaria bicolor was chemically synthesized and optimized to heterogeneous expression in Pichia pastoris and Arabidopsis thaliana. The properties of recombinant laccase expressed by P. pastoris were investigated. The laccase activity was optimal at 3.6 pH and $40^{\circ}C$. It exhibited $K_m$ and $V_{max}$ values of $0.565mmol\;l^{-1}$ and $1.51{\mu}mol\;l^{-1}\;min^{-1}$ for ABTS respectively. As compared with untransformed control plants, the laccase activity in crude extracts of transgenic lines exhibited a 5.4 to 12.4-fold increase. Both laccases expressed in transgenic P. pastoris or A. thaliana could decolorize crystal violet. These results indicated that L. bicolor laccase gene may be transgenically exploited in fungi or plants for dye decolorization.

A comprehensive quality analysis of randomized controlled clinical trials of Asian ginseng and American ginseng based on the CONSORT guideline

  • Chen, Weijie;Li, Xiuzhu;Chen, Zhejie;Hao, Wei;Yao, Peifen;Li, Meng;Liu, Kunmeng;Hu, Hao;Wang, Shengpeng;Wang, Yitao
    • Journal of Ginseng Research
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    • 제46권1호
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    • pp.71-78
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    • 2022
  • Ginseng is an international herb that has been used for thousands of years. Two species most commonly applied and investigated in the ginseng family are Asian ginseng and American ginseng. The number of randomized controlled clinical trials (RCTs) has conspicuously increased, driven by the rapid development of ginseng. However, the reporting of RCT items of ginseng is deficient because of different trial designs and reporting formats, which is a challenge for researchers who are looking for the data with high quality and reliability. Thus, this study focused on providing an extensive analysis of these two species and examined the quality of the RCTs, based on the Consolidated Standards of Reporting Trials (CONSORT) guideline. Ninety-one RCTs conducted from 1980 to 2019 that were related to Asian ginseng and American ginseng used singly met our inclusion criteria. We found that the reporting quality of the two species has improved during the past 40 years. Publication date and sample size were significantly associated with the reporting quality. Rigorous RCTs designed for the species of ginseng are warranted, which can shed light on product research and development of ginseng in the future.

Lipase-catalyzed production of biodiesel

  • Sohn, Jung-Hoon;Kim, So-Young;Lee, Eung-Suek;Choi, Eui-Sung
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2003년도 생물공학의 동향(XIII)
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    • pp.127-128
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    • 2003
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