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Constituents from leaves of Macaranga hemsleyana

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Chinese Herbal Medicines 2024年第3期16卷 481-486页

作者： Joseph Sakah Kaunda Jia liu Yaojun Xu Yuansi Chen Chenfang Yue Xingjie Zhang Ruihan Zhang Muhammad Amin Weilie Xiao Hongliang li xiaoli li Key Laboratory of Medicinal Chemistry for Natural Resource Ministry of EducationYunnan Characteristic Plant Extraction LaboratoryYunnan Provincial Center for Research&Development of Natural ProductsState Key Laboratory for Conservation and Utilization of Bio-Resources in YunnanSchool of PharmacySchool of MedicineChemical Science and TechnologyYunnan UniversityKunming 650500China Yunnan Key Laboratory of Pharmacology for Natural Products Haiyuan CollegeKunming Medical UniversityKunming 650500China

Objective:To study constituents of the leaves of Macaranga hemsleyana,and evaluate their inhibitory effects against NOD-like receptor thermal protein domain associated protein 3(NLRP3)inflammasome activation,and antiproliferative ***:The constituents were isolated and purified by column chromatography on MCI gel CHP20P/P120,silica gel,Sephadex LH-20,and *** structures of compounds were determined by 1D,2D NMR,and HR-ESI-MS *** inhibitory effect of compounds on inflammasome activation was determined by lactate dehydrogenase(LDH)*** antiproliferative activity was evaluated using MTT ***:The study led to the isolation of 23 compounds,including one new compound,identified as(2Z)-3-[4-(β-D-glucopyranosyloxy)-2′-hydroxy-5′-methoxyphenyl]-2-propenoic acid(1),together with 22 known compounds recognized as 1,4-dihydro-4-oxo-3-pyridinecarbonitrile(2),methyl 4-methoxynicotinate(3),4-methoxynicotinonitrile(4),1-(3-O-β-D-glucopyranosyl-4,5-dihydroxyphenyl)-ethanone(5),neoisoastilbin(6),isoastilbin(7),aromadendrin(8),neoastilbin(9),astilbin(10),quercitrin(11),neoschaftoside(12),apigenin 6,8-bis-C-α-L-arabinoside(13),vitexin(14),bergenin(15),scopoletin(16),glucopyranoside salicyl(17),koaburside(18),benzylβ-D-glucoside(19),icariside B5(20),roseoside(21),loliolide(22),and adenosine(23).The tested compounds did not show LDH inhibition nor antiproliferative ***:Compound 1 was a new *** 2 and 3 were obtained for the first time from natural *** 22 known compounds constituted of alkaloids(2–4,23),phenolics(5,15,17,18),flavonoids(6–14),coumarin(16),benzyl glycoside(19),and norsesquiterpenes(20–22).All the compounds,1–23,were revealed from *** for the first *** is the initial uncovering of molecules 1–10,12,13,17–19,and 23 from the genus *** isolated compounds,11,14–16,and 20–22 established taxonomic classification of *** in Euphorbiaceae *** were outstanding as

关键词： antiproliferative activity chemotaxonomic significance flavonoids glycoside Macaranga hemsleyana Pax et Hoffm NLRP3 inflammasome

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铁路货车铸件DR图像的疏松缺陷快速检测

铁道科学与工程学报 2022年第6期19卷 1763-1773页

作者：李小利曾理重庆大学数学与统计学院重庆401331 重庆大学工业CT无损检测教育部工程研究中心重庆400044

快速有效地检测铁路货车铸件的疏松缺陷,对铁路运输安全具有重要意义。数字化X射线照相可以直接获取含有缺陷的铸件图像,成像速度快。但人工目测图像检测法不仅耗时费力容易疲劳,而且依赖于检测人员的经验。研究自动化检测方法实现图像... 详细信息

快速有效地检测铁路货车铸件的疏松缺陷,对铁路运输安全具有重要意义。数字化X射线照相可以直接获取含有缺陷的铸件图像,成像速度快。但人工目测图像检测法不仅耗时费力容易疲劳,而且依赖于检测人员的经验。研究自动化检测方法实现图像缺陷的实时检测具有重要的意义。铸件图像中疏松缺陷形状复杂,可以分为树枝状、羽毛状和海绵状等,也可能是多种不同形状疏松缺陷的组合,这增加了检测识别的难度。发展基于深度学习的铸件数字化射线照相的疏松缺陷检测和识别方法。首先,对铸件数字化射线照相的原始图像进行一系列的预处理,采用引导图像滤波结合分数阶微分对图像进行增强,利用图像标注软件标注增强后的图像,得到标注数据集;然后,将标注数据和含有不同等级的疏松缺陷图像输入到YOLACT深度学习网络中,进行训练和测试。测试结果表明:该方法对单幅图像的平均检测时间为1.48 s,疏松缺陷的平均检测率为60.56%。该方法可快速检测出铸件疏松缺陷的等级和类别,为实时检测工业铸件缺陷提供一种辅助解决方法。

关键词：铁路货车铸件数字化射线照相缺陷检测图像处理深度学习

Asymptotics of the Density-dependent Incompressible Navier-Stokes Flows in Exterior Domains

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Asymptotics of the Density-dependent Incompressible Navier-S...

Predefined-Time Command Filtering Control for High-Order Strict Feedback System

第十一届全国流体力学学术会议

作者： xiaoli li Wenying Meng Department of Mathematics School of ScienceBUPT

In this paper,we investigate the existence and uniqueness of time periodic solution to the density-dependent incompressible Navier-Stokes equations in exterior ***,we study the asymptotic stability of the periodic solution that is given by the same Landau *** we all know,the celebrated results by many mathematicians devoted to the constant density case are ***,an actual fluid is almost impossible homogeneous and *** expect to find an approach to study the solvability of Navier-Stokes equations with variable ***,we employ some technical methods and hypothesis to overcome the difficulties by variable *** theorems in this article can be regarded as an improvement extension by the work in ***,*** and ***-Peng(Communications in Partial Differential Equations,Volume 37,2012-Issue 10).

关键词： Navier-Stokes flows exterior domain existence and uniqueness asymptotic stability

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Predefined-Time Command Filtering Control for High-Order Str...

Fuzzy Finite-Time Tracking Control of Nonlinear Systems with Quantized States and Saturated Quantized Input

第43届中国控制会议

作者： Guoju Zhang xiaoli li Faculty of Information Technology Beijing University of Technology Beijing Key Laboratory of Computational Intelligence and Intelligent System

This article investigates the predefined-time tracking problem for high-order strict feedback *** command filter can not only avoid the "computational complexity explosion" phenomenon in traditional backstepping methods,but also alleviate the chattering problem caused by signum in conventional filters.A novel predefined-time compensation system is proposed to compensate for the decrease in control accuracy caused by filtering ***-time command filtering controller is proposed by combining the backstepping mechanism and predefined-time theory,ensuring that the controlled system converges within a user-defined ***,mathematical simulation demonstrates the rationality and effectiveness of the proposed control scheme.

关键词： Predefined-time stability Modified command filter Error compensation mechanism

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Fuzzy Finite-Time Tracking Control of Nonlinear Systems with...

第43届中国控制会议

作者： Xiaowei Yu xiaoli li Faculty of Information Technology Beijing University of Technology Beijing Key Laboratory of Computational Intelligence and Intelligent System Beijing University of Technology

This paper investigates the issue of adaptive finite-time tracking for nonlinear systems with both quantized input and states. More specially, a saturated quantized input is applied for the input quantization. By constructing a novel high-gain fuzzy state observer, the issues of unknown nonlinearities and discontinuous quantized signals are addressed. Then an adaptive backstepping controller involving the fuzzy logic systems is developed. It is verified that, with the designed control method,all signals of the closed-loop system are bounded, and the tracking error can be made small by choosing the design parameters suitably. Finally, a simulation example is studied to show the effectiveness of the control scheme.

关键词： Quantized States Finite-time Tracking High-gain Observer Fuzzy Logic Systems

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浅论中国“西部电影”的类型化特征

当代电影 2005年第3期 89-91页

作者：李小丽中国传媒大学 2002级硕士研究生100024

认真说来,中国的电影创作,还没有出现完整的类型片模式.解放前的情况就不去多说了.建国后,这一时期虽然出现了一些战争片、反特片等'类型'和'准类型'影片,但这种'类型电影'与西方经典电影理论中的类型电影存在相当大的距离和差别.近期... 详细信息

认真说来,中国的电影创作,还没有出现完整的类型片模式.解放前的情况就不去多说了.建国后,这一时期虽然出现了一些战争片、反特片等'类型'和'准类型'影片,但这种'类型电影'与西方经典电影理论中的类型电影存在相当大的距离和差别.近期中国电影都是零零星星地闪现出一些带有类型片元素的影片,几乎没有宏观的产品布局.

关键词：中国电影创作类型电影 “西部电影”

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论图书馆服务湘西地区旅游

图书馆 2005年第5期 85-87页

作者：李小丽吉首大学图书馆湖南张家界427000

旅游的发展趋势需要图书馆的介入和参与,本文试从图书馆服务旅游的优势提出图书馆服务湘西地区旅游的思路。

关键词：图书馆湘西地区旅游图书馆服务发展趋势

Biological Effects of Nutrient Nualgi on the Water Ecological Environment in Culture Pond

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Animal Husbandry and Feed Science 2016年第6期8卷 369-376页

作者： li Gu Mao Mengzhe li xiaoli Tao ling Gao Maolin Yangtze River Fisheries Research Institute Chinese Academy of Fishery Sciences Wuhan 430223 China Freshwater Aquaculture Collaborative Innovation Center of Hubei Province Wuhan 430070 China

In order to study the short-term effects of Nualgi on water quality and phytoplankton in fishpend, we conducted continuous and regular surveys on the phytoplankton community and the water quality indexes in four groups. The four groups were a Nualgi group （ M1 ）, a diatom group （ M2 ）, a Nualgi and diatom group （M3）, and a control group （C）. The results showed that there were no significance differences in pH, dissolved oxygen （DO）, total nitrogen （TN） and total phosphorus （TP） among the four groups. The IP concentration of groups MI and M3 was significantly lower than that of groups M2 and C, indicating that Nualgl can reduce the IP concentration of water. The concentrations of NH4＋ -N, NO2- -N and CODMn, of groups M1 , M2 and M3 were sigeificantly lower than those of group C, suggesting that both Nualgi and dominant diatom species can adjust water quality by reducing the concentrations of NH4＋ -N, NO2- -N and CODMR. In this test, we identified 186 species that belonged to 109 genera of seven phyla. Among them, 86 species were Chlorophyta, 48 were Bacillariophyta, 27 were Cyanophyta, 17 were Euglenophyta, three were Dinophyta, three were Cryptophyta and two were Chrysophyta. Both diatom species and Nualgi can promote the growth of Bacillariophyta, restrain the growth of Chlorophyta and Cyanophyta, and thus change phytoplankton community structure. The biomass of Bacillariophyta in groups M1, M2 and M3 was larger than that in group C from the 20th d of the experiment, while the biomasses of Chlorophyta and Cyanophyta were lower than that in group C. Melo- sira granulata became the dominant algae species in groups M1, M2 and M3 , while Coelastrum microporum and Crucigenia tetrapedia were the dominant algae species in group Conly. Scenedesmus quadr/cauda became the dominant algae in groups M1 , M2 and C. There was no remarkable difference in diversity index among the four groups. The Shannon-Wiener index in all the four groups were all above 2.00, suggesting that the

关键词： Nualgi Diatom Phytoplankton Pond water quality

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大片中的数字美学

当代电影 2008年第3期 82-85页

作者：李小丽中国传媒大学电影学博士100024

纵观近几年世界范围内的电影大片,如果离开了数字技术,无论大片的投资规模、制作水准和市场魅力恐怕都要大打折扣。技术在电影史上一直使电影产品保持了卓越的品质,这也是不断吸引更多观众的主要动力。本文主要从数字技术对大片产生的... 详细信息

纵观近几年世界范围内的电影大片,如果离开了数字技术,无论大片的投资规模、制作水准和市场魅力恐怕都要大打折扣。技术在电影史上一直使电影产品保持了卓越的品质,这也是不断吸引更多观众的主要动力。本文主要从数字技术对大片产生的奇观效果及其对传统美学提出的挑战以及它在大片中的前景等几方面来阐述数字技术在当下的应用和其体现出的美学效果。

关键词：数字美学大片奇观虚拟与真实情感真实