http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Youxi (검색결과 5 건)
- 무료
- 기관 내 무료
- 유료
-
Synthetic studies of Sepositoside A model systems
Guozhi Xiao,Youxi Chen,Bingfeng Shi,Biao Yu 한국당과학회 2012 한국당과학회 학술대회 Vol.2012 No.1
Saponins, water soluble compounds composed of sugars and steroid or triterpenoid moieties, have attracted considerable interests due to the increased understanding of their wide spectrum of biological and pharmacological activities.Saponins have been found only in marine phylum Echinodermata and particularly in species of the classes Holothuroidea (sea cucumbers) and Asteroidea (starfishes) in the animal kingdom. Starfish extracts and also purified saponins have shown a broad spectrum of physiological and pharmacological activities. In 1981, Sepositoside A, the major saponin, was isolated from the hydrolysate of the Mediterranean starfish Echinaster sepositussaponins mixture(Figure 1). It has a number of unusual features when compared to the more common asterosaponins: it is devoid of the sulphate group and the Δ7, 3β,6β-dioxygenated steroidal nucleus is unprecedented, and, the most remarkable feature is that the trisaccharide chain is cyclized between C-3 and C-6 of the aglycon, giving rise to a highly strain 16-membered macrocyclic ring reminiscent of a crown ether. Sepositoside A had been shown to display antifungal activity, cytotoxic acitivity toward bovine turbinate cells up to a level of 1 μg ml-1 and inhibition of cell division of fertilized sea urchin eggs (ca. 30% inhibition at 10-5 M).Fascinated by the unprecedented highly strain 16-membered macrocyclic molecular structure of Sepositoside A, we contemplated its total synthesis, which might require new synthetic strategies and technologies to close the challenging 16-membered macrocyclic ring by virtue of its expected high strain and lability. Herein, we report our synthetic studies for the construction of 16-membered macrocyclic ring of Sepositoside A model systems.
-
Online health estimation strategy with transfer learning for operating lithium‑ion batteries
Fang Yao,Defang Meng,Youxi Wu,Yakun Wan,Fei Ding 전력전자학회 2023 JOURNAL OF POWER ELECTRONICS Vol.23 No.6
Complex power supply operation conditions complicate the degradation process of lithium batteries, which makes the charge–discharge cycle incomplete and the maximum available capacity not easily accessible. Besides, data-driven methods suffer from limited adaptation and possible overfi tting. This paper proposes an online health estimation strategy with transfer learning for estimating the state of health (SOH) of batteries under varying charge–discharge depths and current rates. It aims to alleviate the diffi culty in estimating SOH for operating batteries, and broaden the application range of the training model. The core of this strategy is a two-domain transfer CNN-LSTM model that estimates targets by transferring the battery degradation trends of multiple constant conditions. First, health indicators (HIs) with relatively high correlations and wide application ranges are extracted from the voltage and current data of the daily charge process. Then HI-based source domain selection criteria are designed. Since the battery experiences full and incomplete-discharged cases leading to various aging rates, a two-domain transfer CNN-LSTM model is designed. Each subnet includes a CNN and an LSTM to accomplish feature adaptation and time series forecasting. The weights of the sub-nets are updated online to track the drift of the time series covariates. Finally, the proposed strategy is verifi ed on target batteries with varying cut-off voltages and currents, which demonstrates notable accuracy and reliability.
-
-
Functional roles of rice glycosyltransferase family GT43 in xylan biosynthesis.
Lee, Chanhui,Teng, Quincy,Zhong, Ruiqin,Yuan, Youxi,Ye, Zheng-Hua Landes Bioscience 2014 Plant signaling & behavior Vol.9 No.1
<P>Xylan is the major hemicellulose present in both primary and secondary cell walls of rice vegetative tissues. Since xylan is one of the factors contributing to biomass recalcitrance, understanding how xylan is synthesized in rice will potentially provide tools to modify grass biomass composition better suited for biofuel production. Studies of xylan biosynthesis in Arabidopsis have revealed that family GT43 glycosyltransferases, which form 2 functionally nonredundant groups, IRX9/IRX9 homolog and IRX14/IRX14 homolog, are required for xylan backbone elongation. The rice genome harbors 10 genes encoding family GT43 members and it is currently unknown whether they are all involved in xylan biosynthesis. In this report, we performed biochemical analysis of xylan xylosyltransferase activity in rice stem microsomes and investigated the roles of 4 representative rice GT43 members, OsGT43A (LOC_Os05 g03174), OsGT43E (LOC_Os05 g48600), OsGT43H (LOC_Os04 g01280), and OsGT43J (LOC_Os06 g47340), in xylan biosynthesis. OsGT43 proteins were shown to be localized in the Golgi, where xylan biosynthesis occurs. Complementation analysis by expression of OsGT43s in Arabidopsis irx9 and irx14 mutants demonstrated that OsGT43A and OsGT43E but not OsGT43H and OsGT43J were able to rescue the mutant phenotypes conferred by the irx9 mutation, including defective stem mechanical strength, vessel morphology, xylan content, GlcA side chains, xylan chain length, and xylosyltransferase activity. On the other hand, OsGT43J but not OsGT43A, OsGT43E, and OsGT43H restored the defective xylan phenotype in the irx14 mutant. These results indicate that the rice GT43 family evolved to retain the involvement of 2 functionally nonredundant groups, OsGT43A and OsGT43E (IRX9 homologs) vs. OsGT43J (an IRX14 homolog), in xylan backbone biosynthesis.</P>
-
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
