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海上丝绸之路超大城市空间扩展遥感监测与分析

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遥感学报 2017年第2期21卷 169-181页

作者：禹丝思孙中昶郭华东赵相伟孙林吴孟凡山东科技大学测绘学院青岛266590 中国科学院遥感与数字地球研究所数字地球重点实验室北京100094 海南省地球观测重点实验室三亚572029 湖南师范大学资源与环境科学学院长沙410006

以海上丝绸之路沿线的11个超大城市为例,基于长时间序列的Landsat MSS/TM/ETM+/OLI和HJ-1卫星CCD数据,利用基于面向对象的支持向量机SVM(Support Vector Machine)分类方法提取20世纪70年代到2015年的城市不透水层,并结合景观格局指数—... 详细信息

以海上丝绸之路沿线的11个超大城市为例,基于长时间序列的Landsat MSS/TM/ETM+/OLI和HJ-1卫星CCD数据,利用基于面向对象的支持向量机SVM(Support Vector Machine)分类方法提取20世纪70年代到2015年的城市不透水层,并结合景观格局指数—最大斑块指数LPI(Largest Patch Index)、斑块密度PD(Patch Density)和欧几里得最邻近距离ENN(Euclidean Nearest Neighbor Distance)分析了超大城市的发展模式。研究结果表明:基于面向对象的SVM分类方法能够高效提取城市不透水层;平均总精度高于87.9%,平均Kappa系数高于0.87;过去40余年,各超大城市的面积扩张了4—13倍,中国和印度的超大城市扩张最快,广州、上海超过12倍;各城市以"中心—边缘"或"沿海—内陆"的方向扩张,表现为"扩散—聚集—再扩散"的扩张模式;总体来看,沿线的城市化进程仍处于上升期。本研究为建设"21世纪海上丝绸之路"提供了科学依据,对当地生态环境保护和新型城镇化建设具有重要意义。

关键词：海上丝绸之路超大城市面向对象的SVM 不透水层景观格局城市化

Immunomodulatory potential of exopolysaccharides from Lactiplantibacillus plantarum YY-112

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Food Science and Human Wellness 2024年

作者： mengfan Luo Wanyi Zhou Wenyang Tao Jianrong Xing Jingrui Li Yuxing Guo Ying Yang Institute of Food Science， Zhejiang Academy of Agricultural Sciences School of Food Science and Pharmaceutical Engineering， Nanjing Normal University

In vitro simulated colonic fermentation studies have shown the prebiotic potential of exopolysaccharides from Lactiplantibacillus plantarum YY-112 (YEPS). Its immunomodulatory effects and related mechanisms were systematically investigated in this study. We observed that YEPS intervene in immune responses and improve intestinal microbial structure in normal mice， including significantly increasing the relative abundance of Enterorhabdus and norank＿f＿＿norank＿o＿＿Clostridia UCG-014 as well as decreasing that of unclassified＿c＿＿Bacilli (P < 0.05). In the immunocompromised mouse model， YEPS decreased IL-6 levels (P < 0.05) and protected the spleen by regulating lymphocyte levels. YEPS preserved the intestinal barrier by improving Mucin 2， Zonula occludens protein 1， and Occludin expression. Moreover， YEPS significantly reduced the relative abundance of Bacillus， unclassified＿c＿＿Bacilli， Lachnoclostridium， Eubacterium＿xylanophilum＿group， and Desulfovibrio (P < 0.05)， potentially enhancing mice immunity by improving the intestinal microbiota associated with immune function. In conclusion， YEPS can be used as a natural functional extract with prebiotic effects that may improve host immunity. This provided the basis for the application of YEPS as a novel potential food additive.

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融合WorldView-2与机载激光雷达数据估算城市不透水面

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遥感信息 2017年第2期32卷 79-88页

作者：吴孟凡孙中昶李慧杨波禹丝思湖南师范大学资源与环境科学学院长沙410006 中国科学院遥感与数字地球研究所数字地球重点实验室北京100094 海南省地球观测重点实验室海南三亚572029 山东科技大学测绘科学与工程学院山东青岛266590

针对高空间分辨率遥感影像进行城市不透水面提取时存在的同物异谱、异物同谱及阴影等局限性,提出一种基于WorldView-2高分影像与机载激光雷达数据融合的分层分类估算城市不透水面的方法。该方法首先运用基于雾霾与比值(haze-and-ratio-b... 详细信息

针对高空间分辨率遥感影像进行城市不透水面提取时存在的同物异谱、异物同谱及阴影等局限性,提出一种基于WorldView-2高分影像与机载激光雷达数据融合的分层分类估算城市不透水面的方法。该方法首先运用基于雾霾与比值(haze-and-ratio-based,HR)的融合算法对WorldView-2多光谱波段与全色波段进行数据融合;然后依据LiDAR归一化数字表面模型(normalization digital surface model,nDSM)高度阈值分为地面物体与非地面物体,运用像元尺度上分层支持向量机分类算法进行城市不透水面百分比估算;最后结合特征阈值和GIS空间分析法探测阴影区域不透水面。研究结果表明,与传统的高分影像提取城市不透水面方法相比,该方法可以明显改善材质复杂的建筑物屋顶提取不完整,以及高亮裸土与高反照度屋顶相互混淆的现象,并通过阴影校正可以较好地区分阴影区域的植被与不透水面信息,进而提高城市不透水面估算精度。

关键词： WorldView-2 激光雷达不透水面 HR融合支持向量机

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烯丙基芳香化合物的电化学选择性氧化酯化

有机化学 2024年第3期44卷 1005-1012页

作者：李梦帆程旭南京大学化学化工学院南京210023

报道了烯丙基芳基化合物的电化学氧化酯化方法,通过同时活化苄位+烯丙位的C—H和C—C键,合成了一系列苯甲酸酯类化合物.本反应展现了良好的化学选择性,优先在苄位+烯丙位发生氧化,而其它的苄位C—H键则保持稳定.该反应在中性条件下进行... 详细信息

报道了烯丙基芳基化合物的电化学氧化酯化方法,通过同时活化苄位+烯丙位的C—H和C—C键,合成了一系列苯甲酸酯类化合物.本反应展现了良好的化学选择性,优先在苄位+烯丙位发生氧化,而其它的苄位C—H键则保持稳定.该反应在中性条件下进行,无需酸碱添加剂,可以适用叔醇酯的构建,同时避免酯和醇存在下的转移酯化副反应.

关键词：烯丙基苄基电化学酯化

Genetic variants in C1GALT1 are associated with gastric cancer risk by influencing immune infiltration

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Journal of Biomedical Research 2024年第4期38卷 348-357页

作者： mengfan Guo Jingyuan Liu Yujuan Zhang Jingjing Gu Junyi Xin Mulong Du Haiyan Chu Meilin Wang Hanting Liu Zhengdong Zhang Departments of Environmental Genomics and Genetic Toxicology the Key Laboratory of Modern Toxicology of Ministry of EducationCenter for Global HealthJiangsu Key Laboratory of Cancer BiomarkersPrevention and TreatmentCollaborative Innovation Center for Cancer Personalized MedicineSchool of Public Health/Institute of Clinical Researchthe Affiliated Taizhou People's Hospital of Nanjing Medical UniversityNanjing Medical UniversityNanjingJiangsu 211166China Departments of Environmental Genomics and Genetic Toxicology the Key Laboratory of Modern Toxicology of Ministry of EducationCenter for Global HealthJiangsu Key Laboratory of Cancer BiomarkersPrevention and TreatmentCollaborative Innovation Center for Cancer Personalized MedicineSchool of Public HealthNanjing Medical UniversityNanjingJiangsu 211166China Department of Bioinformatics School of Biomedical Engineering and InformaticsNanjing Medical UniversityNanjingJiangsu 211166China Department of Biostatistics Center for Global HealthSchool of Public HealthNanjing Medical UniversityNanjingJiangsu 211166China

Core 1 synthase glycoprotein-N-acetylgalactosamine 3-β-galactosyltransferase 1(C1GALT1)is known to play a critical role in the development of gastric cancer,but few studies have elucidated associations between genetic variants in C1GALT1 and gastric cancer *** using the genome-wide association study data from the database of Genotype and Phenotype(dbGAP),we evaluated such associations with a multivariable logistic regression model and identified that the rs35999583 G>C in C1GALT1 was associated with gastric cancer risk(odds ratio,0.83;95% confidence interval[CI],0.75-0.92;P=3.95×10^(-4)).C1GALT1 mRNA expression levels were significantly higher in gastric tumor tissues than in normal tissues,and gastric cancer patients with higher C1GALT1 mRNA levels had worse overall survival rates(hazards ratio,1.33;95%CI,1.05-1.68;P_(log-rank)=1.90×10^(-2)).Furthermore,we found that C1GALT1 copy number differed in various immune cells and that C1GALT1 mRNA expression levels were positively correlated with the infiltrating levels of CD4^(+)T cells and *** results suggest that genetic variants of C1GALT1 may play an important role in gastric cancer risk and provide a new insight for C1GALT1 into a promising predictor of gastric cancer susceptibility and immune status.

关键词： O-glycosylation genetic variants immune status gastric cancer

Ballistic performances of the hourglass lattice sandwich structures under high-velocity fragments

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Defence Technology（防务技术） 2024年第1期31卷 312-325页

作者： He-xiang wu Jia Qu Lin-zhi wu Key Laboratory of Advanced Ship Materials and Mechanics College of Aerospace and Civil EngineeringHarbin Engineering UniversityHarbin150001China School of Civil Engineering Northeast Forestry UniversityHarbin150040China

In this paper,the numerical simulation method is used to study the ballistic performances of hourglass lattice sandwich structures with the same mass under the vertical incidence of *** is paid to elucidating the influences of rod cross-section dimensions,structure height,structure layer,and rod inclination angle on the deformation mode,ballistic performances,and ability to change the ballistic direction of *** results show that the ballistic performances of hourglass lattice sandwich structures are mainly affected by their structural *** this respect,structural parameters optimization of the hourglass lattice sandwich structures enable one to effectively improve their ballistic limit velocity and,consequently,ballistic performances.

关键词： Hourglass lattice sandwich structures Ballistic performances high-velocity Finite element analysis

Resilience-incorporated seismic risk assessment of precast concrete frames with“dry”connections

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 403-425页

作者： wu Chenhao Tang Yuchuan Cao Xuyang wu Gang Key Laboratory of Concrete and Prestressed Concrete Structures of the Ministry of Education Nanjing 211102China Department of Civil and Environmental Engineering University of CaliforniaLos AngelesCA 90095USA School of Civil Engineering Southeast UniversityNanjing 211102China College of Civil and Transportation Engineering Hohai UniversityNanjing 210024China

A resilience-incorporated risk assessment framework is proposed and demonstrated in this study to manifest the advantageous seismic resilience of precast concrete frame(PCF)structures with“dry”connections in terms of their low damage and rapid *** framework integrates various uncertainties in the seismic hazard,fragility,capacity,demand,loss functions,and post-earthquake *** this study,the PCF structures are distinguished from ordinary reinforced concrete frame(RCF)structures by characterizing multiple limit states for the PCF based on its unique damage ***,probabilistic story-wise pushover analyses are performed to yield story-wise capacities for the predefined limit *** the seismic resilience analysis,a step-wise recovery model is proposed to idealize the functionality recovery process,with separate considerations of the repair and non-repair *** recovery model leverages the economic loss and downtime to delineate the stochastic post-earthquake recovery curves for the resilience loss *** such,contingencies in the probabilistic post-earthquake repairs are incorporated and the empirical judgments on the recovery parameters are largely *** proposed framework is demonstrated through a comparative study between two“dry”connected PCFs and one RCF designed as alternative structural systems for a prototype *** results from the risk quantification indicate that the PCFs show reduced loss hazards and lower expected losses relative to the ***,the PCF equipped with energy dissipation devices at the“dry”connections largely reduces the expected economic loss,downtime,and resilience loss by 29%,56%,and 60%,respectively,compared to the RCF.

关键词： precast concrete frame non-emulative precast system seismic resilience seismic risk functional recovery

β-catenin在淇河鲫不同组织中的表达研究

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河南水产 2023年第1期 22-25页

作者：吴梦帆吴利敏河南师范大学水产学院河南新乡453007

β-连环蛋白(CTNNB1,β-catenin)是一种存在于细胞膜、细胞质和细胞核的多种功能性胞内蛋白,在动物胚胎发育和器官发生中起着重要作用。为了研究β-catenin在淇河鲫(Carassius auratus in Qihe river)体内各组织中的表达模式,本实验用... 详细信息

β-连环蛋白(CTNNB1,β-catenin)是一种存在于细胞膜、细胞质和细胞核的多种功能性胞内蛋白,在动物胚胎发育和器官发生中起着重要作用。为了研究β-catenin在淇河鲫(Carassius auratus in Qihe river)体内各组织中的表达模式,本实验用免疫组化法检测β-catenin在孵化后10天淇河鲫的眼、脑、鳃、软骨、肠、肝、脾、肾和孵化后120天的卵巢组织的表达情况。结果显示,β-catenin在肠的杯状细胞,肾小管上皮细胞,鳃小片的泌氯细胞,肝组织的肝细胞,脾脏的巨噬细胞,脑组织的中脑和间脑的支持细胞,卵巢组织的Ⅰ期和Ⅱ期卵母细胞,软骨的软骨基质和软骨膜以及眼组织的全视网膜、色素层和晶状体中表达。以上结果暗示,淇河鲫β-catenin可能参与了器官的发育过程。这些数据将为了解β-catenin调控硬骨鱼器官发生的分子机制提供参考。

关键词： β-catenin 淇河鲫免疫定位

New findings on the influence of El Nino events on tropical cyclone formation

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Science China Earth Sciences 2024年第3期67卷 892-893页

作者： Liguang wu Department of Atmospheric and Oceanic Sciences Institute of Atmospheric SciencesFudan UniversityShanghai 200438China

Tropical cyclones typically form over warm tropical and subtropical ocean surfaces, as their formation and intensification rely primarily on the energy provided by the ocean. Pioneering research by Gray (1968) revealed that the formation of tropical cyclones requires the sea surface temperature (SST) to be no less than 26.5℃. Consequently, SST is commonly recognized as a crucial parameter among the environmental factors influencing tropical cyclone formation(Gray, 1979;Emanuel and Nolan, 2004).

关键词： tropical cyclone ocean