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Development of a region-partitioning method for debris flow susceptibility mapping

Journal of Mountain Science 2021年第5期18卷 1177-1191页

作者： qiao shuang-shuang QIN Sheng-wu SUN Jing-bo CHE Wen-chao YAO Jing-yu SU Gang CHEN Yang NNANWUBA Uzodigwe Emmanuel College of Construction Engineering Jilin UniversityChangchun 130026China

Debris flow susceptibility mapping(DFSM)has been reported in many studies,however,the irrational use of the same conditioning factor system for DFSM in regional-scale has not been thoroughly *** this paper,a region-partitioning method that is based on the topographic characteristics of watershed units was developed with the objective of establishing multiple conditioning factor systems for regional-scale ***,watershed units were selected as the mapping units and created throughout the entire research *** topographical factors,namely,elevation,slope,aspect and relative height difference,were selected as the basis for clustering watershed *** k-means clustering analysis was used to cluster the watershed units according to their topographic characteristics to partition the study area into several ***,the information gain ratio method was used to filter out superfluous factors to establish conditioning factor systems in each region for the subsequent debris flow susceptibility ***,a debris flow susceptibility map of the whole study area was acquired by merging the maps from all *** of Yongji County in Jilin Province,China was selected as a case study,and the analytical hierarchy process method was used to conduct a comparative analysis to evaluate the performance of the region-partitioning *** area under curve(AUC)values showed that the partitioning of the study area into two parts improved the prediction rate from 0.812 to *** results demonstrate that the region-partitioning method on the basis of topographic characteristics of watershed units can realize more reasonable regional-scale ***,the developed region-partitioning method can be used as a guide for regional-scale DFSM to mitigate the imminent debris flow risk.

关键词： Debris flow susceptibility Regionpartitioning method Multiple conditioning factor systems Watershed units Topographic characteristics Yongji county

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结构参量对左手材料通带位置影响的研究

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物理学报 2011年第10期60卷 693-698页

作者：弓巧侠赵双双段智勇马凤英郑州大学物理工程学院郑州450001

基于金属短板对和连续金属线(short-slab pair and continuous wires)复合结构,从理论上系统地研究了在THz波段结构参量对左手材料通带位置的影响.数值模拟结果表明,改变金属板宽度或厚度、连续金属线的长度或厚度都会引起左手材料通带... 详细信息

基于金属短板对和连续金属线(short-slab pair and continuous wires)复合结构,从理论上系统地研究了在THz波段结构参量对左手材料通带位置的影响.数值模拟结果表明,改变金属板宽度或厚度、连续金属线的长度或厚度都会引起左手材料通带位置向较高频段偏移.

关键词：负折射左手材料结构参量通带

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不同培养基对蝉花培养物核苷类成分的影响

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药物评价研究 2016年第5期39卷 804-812页

作者：张忠亮陈桃宝尹彬崔俏俏张霜霜王玉芹浙江泛亚生命科学研究院浙江平湖314200 浙江泛亚生物医药股份有限公司浙江平湖314200

目的建立高效液相色谱(HPLC)法同时检测蝉花培养物4种核苷类成分,分析不同斜面培养基及固体培养基对4种核苷类成分的影响。方法建立4种核酸类成分——尿苷、鸟苷、腺苷、N6-(2-羟乙基)腺苷的HPLC检测方法,应用Waters Symmetry shield TM... 详细信息

目的建立高效液相色谱(HPLC)法同时检测蝉花培养物4种核苷类成分,分析不同斜面培养基及固体培养基对4种核苷类成分的影响。方法建立4种核酸类成分——尿苷、鸟苷、腺苷、N6-(2-羟乙基)腺苷的HPLC检测方法,应用Waters Symmetry shield TMRP C18(250 mm×4.6 mm,5μm)色谱柱;流动相为水-甲醇,梯度洗脱;体积流量1.0 m L/min;柱温30℃;进样量10μL;检测波长260 nm;外标法测定4种核苷类成分水平。对包括假单胞菌选择培养基(PSA)、沙氏葡萄糖琼脂培养基(SDAY,1 000 m L中含葡萄糖量分别为20、30、40 g)在内的斜面培养基和包括江苏农垦(SCM)、烟农24(YN-24)、烟农15(YN-15)、济麦22(JM-22)在内的固体培养基培养的蝉花培养物中4种核酸类成分水平进行测定,利用SPSS16.0统计软件对测定结果进行多重统计分析,验证并找出引起差异的原因。结果建立的HPLC法,4种核苷类成分分离度良好,精密度、稳定性、重复性、加样回收率、耐用性均符合要求;4种不同的斜面培养基对尿苷成分基本无影响(P>0.05),PSA对腺苷、鸟苷、N6-(2-羟乙基)腺苷的水平有明显促进作用(P<0.05);固体培养基SCM的4种核苷类成分的水平较高。结论培养基种类对蝉花培养物核苷类成分变化有直接的影响,确定蝉花虫草的生产工艺时,应充分考虑培养基的选择,同时结合产品成分和生产成本等因素进行综合评价。

关键词：蝉花培养物尿苷鸟苷腺苷 N6-(2-羟乙基)腺苷高效液相色谱培养基

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基于神经网络模型的斜坡地质灾害易发性评价:以吉林永吉为例

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世界地质 2019年第4期38卷 1166-1176页

作者：刘飞秦胜伍乔双双窦强扈秀宇吉林大学建设工程学院

吉林省永吉县存在大量的斜坡地质灾害,为了给永吉县斜坡地质灾害的防治和预警提供高效直观的分析模型,将吉林省永吉县作为研究区,选取高程、坡度、坡向、剖面曲率、平面曲率、距断层距离、岩性、距河流距离、年均降雨量、地形湿度指数... 详细信息

吉林省永吉县存在大量的斜坡地质灾害,为了给永吉县斜坡地质灾害的防治和预警提供高效直观的分析模型,将吉林省永吉县作为研究区,选取高程、坡度、坡向、剖面曲率、平面曲率、距断层距离、岩性、距河流距离、年均降雨量、地形湿度指数和植被覆盖指数等11个评价因子,利用神经网络模型进行区域斜坡地质灾害易发性分析,再选用频率比、支持向量机模型进行对比。利用ROC曲线对模型的准确性进行验证分析,得出神经网络、频率比和支持向量机模型的成功率分别是91.3%、89.3%、90.2%,预测率分别是87.3%、84.3%、85.6%。结果表明:神经网络模型的精度最高,更适用于永吉县斜坡地质灾害的易发性评价。

关键词：斜坡地质灾害易发性评价神经网络频率比支持向量机永吉县

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基于Stacking集成学习的泥石流易发性评价:以四川省雅江县为例

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世界地质 2021年第1期40卷 175-184页

作者：苏刚秦胜伍乔双双扈秀宇陈阳车文超吉林大学建设工程学院长春130000

为给四川省雅江县提供直观准确的泥石流易发性图,将四川省雅江县作为研究区,选用高程、坡度、坡向、地形起伏度、平面曲率、剖面曲率、年平均降雨、到河流的距离、到道路的距离、地形湿度指数、归一化差分植被指数及土壤类型12个评价因... 详细信息

为给四川省雅江县提供直观准确的泥石流易发性图,将四川省雅江县作为研究区,选用高程、坡度、坡向、地形起伏度、平面曲率、剖面曲率、年平均降雨、到河流的距离、到道路的距离、地形湿度指数、归一化差分植被指数及土壤类型12个评价因子,利用Stacking集成学习框架,结合支持向量机、神经网络和随机森林,建立了一种多模型融合的泥石流预测模型。通过ROC曲线验证了模型的准确性,得出Stacking融合模型、随机森林、神经网络和支持向量机模型的成功率分别是98.1%、96.1%、94.5%、93.4%,预测率分别是95.5%、91.6%、90.6%、89.7%。结果表明:Stacking融合模型精度最高,最适合用于雅江县泥石流易发性评价。

关键词：泥石流易发性 Stacking集成学习随机森林支持向量机神经网络雅江县

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Atomic-layer-deposited （ALD） Al2O3passivation dependent interface chemistry, band alignment and electrical properties of HfYO/Si gate stacks

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Journal of Materials Science & Technology 2019年第5期35卷 769-776页

作者： shuang Liang Gang He Die Wang Fen qiao School of Physics and Materials Science Radiation Detection Materials & Devices Lab Anhui UniversityHefei 230601 China Institute of Physical Science and Information Technology Anhui University Hefei 230601 China School of Energy & Power Engineering Jiangsu University Zhenjiang 212013 China

In this work, the effects of atomic-layer-deposited(ALD) Al2O3 passivation layers with different thicknesses on the interface chemistry and electrical properties of sputtering-derived HfYO gate dielectrics on Si substrates have been investigated. The results of electrical measurements and X-ray photoelectron sepectroscopy(XPS) showed that 1-nm-thick Al2O3 passivation layer is optimized to obtain excellent electrical and interfacial properties for HfYO/Si gate stack. Then, the metal-oxide-semiconductor capacitors with HfYO/1-nm Al2O3/Si/Al gate stack were fabricated and annealed at different temperatures in forming gas(95% N2+5% H2). Capacitance-voltage(C-V) and current density-voltage(J-V) characteristics showed that the 250℃-annealed HYO high-k gate dielectric thin film demonstrated the lowest border trapped oxide charge density(-3.3 × 1010 cm-2), smallest gate-leakage current(2.45 × 10-6 A/cm2 at 2 V)compared with other samples. Moreover, the annealing temperature dependent leakage current conduction mechanism for Al/HfYO/Al2O3/Si/Al MOS capacitor has been investigated systematically. Detailed electrical measurements reveal that Poole-Frenkle emission is the main dominant emission in the region of low and medium electric fields while direct tunneling is dominant conduction mechanism at high electric fields.

关键词： Al2O3passivation layer Co-sputtering HYO films Annealing Electrical properties Conduction mechanism

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Spatio-temporal analysis of the melt onset dates over Arctic sea ice from 1979 to 2017

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Acta Oceanologica Sinica 2022年第4期41卷 146-156页

作者： shuang Liang Jiangyuan Zeng Zhen Li Dejing qiao Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100094China State Key Laboratory of Remote Sensing Science Aerospace Information Research InstituteChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China College of Surveying and Geo-Informatics North China University of Water Resources and Electric PowerZhengzhou 450045China

The melt onset dates(MOD)over Arctic sea ice plays an important role in the seasonal cycle of sea ice surface properties,which impacts Arctic surface solar radiation absorbed by the ice-ocean *** interannual variations in MOD is valuable for understanding climate *** this study,we investigated the spatio-temporal variability of MOD over Arctic sea ice and 14 Arctic sub-regions in the period of 1979 to 2017 from passive microwave satellite data.A set of mathematical and statistical methods,including the Sen’s slope and Mann-Kendall mutation tests,were used to comprehensively assess the variation trend and abrupt points of MOD during the past 39 years for different Arctic ***,the correlation between Arctic Oscillation(AO)and MOD was *** results indicate that:(1)all Arctic sub-regions show a trend toward earlier MOD except the Bering Sea and *** *** East Siberian Sea exhibits a significantly earlier trend,with the highest rate of-9.45 d/decade;(2)the temporal variability and statistical significance of MOD trend exhibit large interannual differences with different time windows for most regions in the Arctic;(3)during the past 39 years,the MOD changed abruptly in different years for different sub-regions;(4)the seasonal AO has more influence on MOD than monthly *** findings in this study can improve our knowledge of MOD changes and are beneficial for further Arctic climate change study.

关键词： Arctic sea ice melt onset dates spatio-temporal analysis abrupt changes Arctic Oscillation

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2-hydroxy-3-methyl anthraquinone promotes apoptosis and inhibits invasion of human hepatocellular carcinoma cells by targeting nicotinamide adenine dinucleotide-dependent protein deacetylase sirtuin-1/cellular tumor antigen p53 signaling pathway

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Journal of Traditional Chinese Medicine 2024年第6期44卷 1104-1110页

作者： WU shuang LI qiao ZHU Xieying ZHANG Taoyuan Clinical Laboratory Affiliated Children Hospital of Xi'an Jiaotong UniversityXian 710003China Department of Anesthesiology Rizhao International Heart HospitalRizhao 276800China

OBJECTIVE: To investigate the anti-liver cancer effect of 2-hydroxy-3-methyl anthraquinone(HMA) and the specific mechanism based on nicotinamide adenine dinucleotidedependent protein deacetylase sirtuin-1(SIRT1)/cellular tumor antigen p53(p53) pathway. METHODS: Cell counting kit-8 method was used to observe the effect of HMA on the activity of human hepatocellular carcinoma cells(Hep G2) cells. At 72 h and 80 μL HMA, the apoptosis rate of Hep G2 cells in each group was measured by flow cytometry. Transwell was used to assay for cell invasion. The protein expression levels of SIRT1, p53, B-cell lymphoma-2(Bcl-2), Bcl-2 associated X protein(Bax), caspase-9(CASP9) and caspase-3(CASP3) were detected by Western Blot. RESULTS: HMA significantly inhibited the proliferation of Hep G2 cells, The half inhibiting concentration(IC50) of the HMA at 24, 48 and 72 h were examined and it were 126.3, 98.6, and 80.55 μM, respectively. Compared with the control group, the apoptosis rate of HMA, Selisistat(EX527), and HMA+ EX527 groups enhanced, while the apoptosis rate of SRT1720 diminished, demonstrating that inhibition of SIRT1 can lead to apoptosis of Hep G2 cells. HMA+ EX527 group had the highest apoptosis rate, the lowest expression of SIRT1 and Bcl-2, and the highest expression of p53, Bax, CASP9 and CASP3. The number of invasions of Hep G2 was significantly reduced after HMA and EX527 intervened. Western blot shows HMA could inhibit SIRT1, promote the expression of p53, and decrease the ratio of Bcl-2/Bax. CONCLUSIONS: HMA induced apoptosis in Hep G2 cells, while inhibiting proliferation and invasion. The mechanism of HMA against HCC may be related to the SIRT1/p53 pathway.

关键词： 2-hydroxy-3-methylanthraquinone carcinoma hepatocellular apoptosis invasion sirtuin 1 genes p53

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Existence of Global Attractor for a 3D Brinkman-Forchheimer Equation in Some Poincaré Unbounded Domains

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Wuhan University Journal of Natural Sciences 2023年第4期28卷 282-290页

作者： SONG Xueli XU shuang qiao Baoming College of Science Xi'an University of Science and TechnologyXi'an 710054ShaanxiChina

In this paper, we study the existence of global attractor of a class of three-dimensional Brinkman-Forchheimer equation in some unbounded domains which satisfies Poincaré inequality. We use the tail estimation method to establish the asymptotic compactness of the solution operator and then prove the existence of the global attractor in(H_0~1(Ω))~3.

关键词： Brinkman-Forchheimer equation global attractor asymptotic compactness tail estimation method

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Unlocking the potential of transdermal drug delivery

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International Journal of Smart and Nano Materials 2024年第3期15卷 432-468页

作者： shuang Li Jianhao Wu Xiangjun Peng Xi-qiao Feng Institute of Biomechanics and Medical Engineering Applied Mechanics LaboratoryDepartment of Engineering MechanicsTsinghua UniversityBeijingChina

Transdermal drug delivery(TDD)has gained clinical approval over several decades,with extensive research dedicated to novel drug and device *** notable research progress,the mar-ket adoption of TDD devices has not met anticipated levels,with oral administration and injection remaining predominant delivery *** maximize the potential of TDD,we identify bottlenecks hinder-ing its widespread clinical application and propose promising research *** begin by analyzing stringent demands necessary to truly benefit patients,addressing significant challenges in biomechanics,nanomedicine,and flexible ***,we delve into skin anatomy,enhancement strategies,nano-carriers,and their under-lining mechanisms,highlighting the importance and framework of quantitative *** on these discussions,we highlight the core strength of TDD,such as automatic precise administration based on feedback and high delivery efficiencies,especially applicable to localized conditions(e.g.,central nervous system diseases,tumors).Finally,we envision the future of intelligent TDD device and its opera-tion scenario,aiming to steer research efforts toward faster translation of laboratory innovations into widely used products for sufferers.

关键词： Transdermal drug delivery biomechanics nanomedicine flexible electronics

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