RISS 학술연구정보서비스

검색
다국어 입력

http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.

변환된 중국어를 복사하여 사용하시면 됩니다.

예시)
  • 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
  • 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
닫기
    인기검색어 순위 펼치기

    RISS 인기검색어

      검색결과 좁혀 보기

      선택해제
      • 좁혀본 항목 보기순서

        • 원문유무
        • 원문제공처
          펼치기
        • 등재정보
        • 학술지명
          펼치기
        • 주제분류
          펼치기
        • 발행연도
          펼치기
        • 작성언어
        • 저자
          펼치기

      오늘 본 자료

      • 오늘 본 자료가 없습니다.
      더보기
      • 무료
      • 기관 내 무료
      • 유료
      • Model-Deviation Compensation Control for Uncertain Systems with Time Delay

        Xiao-Jie Sun,Hua Ye,Shu-Min Fei 제어로봇시스템학회 2010 제어로봇시스템학회 국제학술대회 논문집 Vol.2010 No.10

        A novel model-deviation compensation control strategy is developed for a class of uncertain systems with time delay in this paper. Taking an identified second-order plus dead-time (SOPDT) process for example, the whole design methodology is proposed, which integrates the prediction model, the sliding function design, the equivalent control term and the model-deviation compensation control law. Firstly the delay-ahead predictor with the feedback correction is constructed to weaken the affection of time delay in the system. Then by improving the classical sliding mode control, after obtaining the equivalent control term, the model-deviation compensation term is derived from the actual regulated response and the deviation to be eliminated, so that the modeling uncertainties and external disturbances can be restrained. Finally the establishment and feasible solution of LMI guarantee that the system output reaches the desired value. The simulation results verify the effectiveness of the proposed strategy.

      • KCI등재

        Protective Effects of Persimmon Leaf and Fruit Extracts against Acute Ethanol-Induced Hepatotoxicity

        Jie Ma,Xiao-yu Liu,Kyung-Hee Noh,Myo-Jeong Kim,Young-Sun Song 한국식품영양과학회 2007 Preventive Nutrition and Food Science Vol.12 No.4

        Persimmon is well-known as a Korean traditional medicine for alleviating coughs and enhancing blood circulation; it is also used for treatment of hypertension, cancer, diabetes and atherosclerosis. To evaluate the protective properties of persimmon leaf methanol extract (PLME) and persimmon fruit methanol extract (PFME) administration on acute ethanol-induced hepatotoxicity, C57BL/6 male mice were gavaged with or without persimmon extracts for 1 week. Hepatotoxicity was then induced by gavage of 5 g/㎏ BW ethanol. After 12 hr of ethanol administration, blood and liver were collected and analyzed for biochemical markers of hepatotoxicity. The results showed PLME and PFME treatments decreased the activities of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) compared with ethanol control. Both PLME and PFME reduced serum lactate dehydrogenase (LDH) activity, but elevated alcohol dehydrogenase (ADH) activity. Serum triglyceride (TG) and hepatic cholesterol levels were significantly decreased when treated with PLME and PFME. Liver malondialdehyde (MDA) levels were significantly decreased in PLME and PFME groups compared with ethanol control. Furthermore, the administration of PLME and PFME significantly increased the activities of catalase, glutathione peroxidase (GSH-Px) and glutathione reductase (GSH-red). In summary, PLME and PFME appeared to prevent hepatic injury by accelerating alcohol metabolism by increasing alcohol-metabolizing enzyme activities, by activating the antioxidative enzyme system against oxidative stress, and by decreasing fat accumulation, which is evidenced by decreased hepatotoxic indices in serum.

      • KCI등재

        Cross-sectional geometry dependence of spontaneous phase transformation of copper nanowires

        Xiao-Yu Sun,Wen-Ping Wu,Xue-Lin Dong,Yuan-Jie Xu 한국물리학회 2015 Current Applied Physics Vol.15 No.3

        Molecular dynamics simulations have been performed to investigate the spontaneous phase transformation of copper nanowires. It is found that the spontaneous phase transformation exhibits distinct dependence on the cross-sectional geometry of the nanowires and can lead to the reconstruction of atoms into different atomistic configurations, e.g., pure hexagonal-close-packed crystals, fivefold deformation twins, and core/shell structures. For single-crystal copper nanowires, the critical crosssectional size, above which no spontaneous phase transformation can occur, is determined. The physical mechanisms underlying the complicated transformation behavior are analyzed from the viewpoints of energy and stresses.

      • SCOPUSKCI등재

        Novel 5-Fluorouracil Derivatives: Synthesis and Cytotoxic Activity of 2-Butoxy-4-Substituted 5-Fluoropyrimidines

        Sun, Jian,Zhang, Shi-Jie,Li, Hai-Bo,Zhou, Wei,Hu, Wei-Xiao,Shan, Shang Korean Chemical Society 2013 Bulletin of the Korean Chemical Society Vol.34 No.5

        Twenty two new 5-fluorouracil (5-FU) derivatives, 2-butoxy-4-substituted 5-fluoropyrimidines, were synthesized and characterized by IR, $^1H$ NMR, MS, HRMS. All compounds were preliminarily evaluated by MTT assay on human liver BEL-7402 cancer cell line in vitro. Ten compounds were selected to test their cytotoxic activity against A549, HL-60 and MCF-7 cancer cell lines in vitro. These compounds were more sensitive to BEL-7402 than other cell lines, particularly, cytotoxic activity of compounds 6b, 6d-f, 6p, 6s-u were in sub-micromolar scale. The highest cytotoxic potency against A549, HL-60 and MCF-7 was shown by 2-butoxy-4-chloro-5-fluoropyrimidine (5) with $IC_{50}$ values of 0.10, 1.66 and $0.59{\mu}M$, respectively. Compounds 6d and 6e were effective against MCF-7 with $IC_{50}$ $9.73{\mu}M$ and HL-60 with $IC_{50}$ $8.83{\mu}M$, respectively.

      • KCI등재

        Molecular Cloning and Characterization of a Novel Cold-Adapted Family VIII Esterase from a Biogas Slurry Metagenomic Library

        ( Xiao Jie Cheng ),( Xu Ming Wang ),( Tian Lei Qiu ),( Mei Yuan ),( Jiang Uang Sun ),( Jun Lian Gao ) 한국미생물 · 생명공학회 2014 Journal of microbiology and biotechnology Vol.24 No.11

        A novel esterase gene, est01, was successfully unearthed from a biogas digester microbiota metagenomic library. The 1,194 bp est01 gene encodes a protein of 44,804 Da (designated Est01). The amino acid sequence of Est01 shows only moderate (33%) identity to a lipase/ esterase. Phylogenetic analysis and biochemical characterization confirmed that Est01 is a new member of family VIII esterases. The purified Est01 from recombinant Escherichia coli BL21 (DE3) showed high hydrolytic activity against short-chain fatty acid esters, suggesting that it is a typical carboxylesterase rather than a lipase. Furthermore, the Est01 was even active at 10°C (43% activity remained), with the optimal temperature at 20°C, and had a broad pH range from 5.0 to 10.0, with the optimal pH of 8.0. These properties suggest that Est01 is a cold-adaptive esterase and could have good potential for low-temperature hydrolysis application.

      • Electromagnetic Field Exposure and Male Breast Cancer Risk: A Meta-analysis of 18 Studies

        Sun, Jing-Wen,Li, Xiao-Rong,Gao, Hong-Yu,Yin, Jie-Yun,Qin, Qin,Nie, Shao-Fa,Wei, Sheng Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.1

        Background: The possibility that electromagnetic fields (EMF) exposure may increase male breast cancer risk has been discussed for a long time. However, arguments have been presented that studies limited by poor quality could have led to statistically significant results by chance or bias. Moreover, data fo the last 10 years have not been systematically summarized. Methods and Results: To confirm any possible association, a meta-analysis was performed by a systematic search strategy. Totals of 7 case-control and 11 cohort studies was identified and pooled ORs with 95% CIs were used as the principal outcome measures. Data from these studies were extracted with a standard meta-analysis procedure and grouped in relation to study design, cut-off point, exposure assessment method, adjustment and exposure model. A statistical significant increased risk of male breast cancer with EMF exposure was defined (pooled ORs = 1.32, 95% CI = 1.14-1.52, P < 0.001), and subgroup analyses also showed similar results. Conclusions: This meta-analysis suggests that EMF exposure may be associated with the increase risk of male breast cancer despite the arguments raised.

      • Depression and the Risk of Breast Cancer: A Meta-Analysis of Cohort Studies

        Sun, Hui-Lian,Dong, Xiao-Xin,Cong, Ying-Jie,Gan, Yong,Deng, Jian,Cao, Shi-Yi,Lu, Zu-Xun Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.8

        Background: Whether depression causes increased risk of the development of breast cancer has long been debated. We conducted an updated meta-analysis of cohort studies to assess the association between depression and risk of breast cancer. Materials and Methods: Relevant literature was searched from Medline, Embase, Web of Science (up to April 2014) as well as manual searches of reference lists of selected publications. Cohort studies on the association between depression and breast cancer were included. Data abstraction and quality assessment were conducted independently by two authors. Random-effect model was used to compute the pooled risk estimate. Visual inspection of a funnel plot, Begg rank correlation test and Egger linear regression test were used to evaluate the publication bias. Results: We identified eleven cohort studies (182,241 participants, 2,353 cases) with a follow-up duration ranging from 5 to 38 years. The pooled adjusted RR was 1.13(95% CI: 0.94 to 1.36; $I^2=67.2%$, p=0.001). The association between the risk of breast cancer and depression was consistent across subgroups. Visual inspection of funnel plot and Begg's and Egger's tests indicated no evidence of publication bias. Regarding limitations, a one-time assessment of depression with no measure of duration weakens the test of hypothesis. In addition, 8 different scales were used for the measurement of depression, potentially adding to the multiple conceptual problems concerned with the definition of depression. Conclusions: Available epidemiological evidence is insufficient to support a positive association between depression and breast cancer.

      • KCI등재

        Pipeline transport of heavy crudes as stable foamy oil

        Jie Sun,Jiaqiang Jing,Cheng Wu,Fei Xiao,Xiaoxuan Luo 한국공업화학회 2016 Journal of Industrial and Engineering Chemistry Vol.44 No.-

        A new idea was proposed to transport heavy crudes as foamy oil at normal temperature. The effects offoaming agent type and concentration, foam stabilizer type and concentration, oil–water volume ratioand temperature on the formation and stability of foamy oil were evaluated. The foamy oil properties anddrag characteristics of foamy oilflow in small diameter pipes were investigated. The results indicate thatthe prepared stable foamy oil could be characterized as non-Newtonian power lawfluid. The predictedpressure drops were in good agreement with the measured ones. The significant dynamic viscosityreduction rates were obtained.

      • KCI등재

        Protective Effect of Dandelion Extracts on Ethanol-Induced Acute Hepatotoxicity in C57BL/6 Mice

        Xiao-Yu Liu,Jie Ma,Chung-Mu Park,Hee-Kyung Chang,Young-Sun Song 한국식품영양과학회 2008 Preventive Nutrition and Food Science Vol.13 No.4

        Dandelion (Taraxacum officinale) has been widely used as an anti-inflammatory agent in oriental medicine. In the current study, we investigated the protective effect, and the possible mechanism, of dandelion extracts against ethanol-induced acute hepatotoxicity in C57BL/6 mice. Dandelion water and ethanol extract was administered at 2 g/㎏ body weight (BW) once daily for 7 consecutive days, whereas control and ethanol groups received water by gavage. Ethanol (50% ethanol; 6 g/㎏ BW) was administered 12 hr before sacrificing the mice in order to generate liver injury. Significantly increased serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities as well as liver triglyceride (TG) and cholesterol levels were attenuated by dandelion supplementation. In addition, dandelion extracts not only enhanced alcohol dehydrogenase (ADH) and anti-oxidative enzyme activities, but reduced lipid peroxidation. Cytochrome P450 2E1 (CYP 2E1), one of the critical enzymes xenobiotic metabolism, expression was lower with ethanol treatment but restored by dandelion supplementation. These results were confirmed by improved histopathological changes in fatty liver and hepatic lesions induced by ethanol. In conclusion, dandelion could protect liver against ethanol administration by attenuating of oxidative stress and inflammatory responses.

      연관 검색어 추천

      이 검색어로 많이 본 자료

      활용도 높은 자료

      해외이동버튼