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基于双层协作机制的双向行人流仿真模型

西南交通大学学报 2013年第4期48卷 688-693,744页

作者：童蔚苹程琳东南大学交通学院江苏南京210096

针对现有行人仿真模型在行为特性表示不全面和建筑物空间结构表达、空间单元状态的动态存储及转换、仿真过程及结果可视化等方面存在的缺陷,提出了基于双层协作机制的双向行人流仿真模型.通过对南京地铁新街口站换乘通道内行人行为的实... 详细信息

针对现有行人仿真模型在行为特性表示不全面和建筑物空间结构表达、空间单元状态的动态存储及转换、仿真过程及结果可视化等方面存在的缺陷,提出了基于双层协作机制的双向行人流仿真模型.通过对南京地铁新街口站换乘通道内行人行为的实地观测,全面分析了行人在双向通道内的行为特征.在模型中的通道环境层,利用GIS技术进行栅格化并存入空间数据库,在仿真输出阶段应用可视化引擎将场景输出至图形界面;在行人行为层,基于Multi-agent和CA理论建立行人行为决策模型,构建的智能体考虑了行人个体特性和行为.通过计算机仿真,揭示了平均速度与仿真时间步、行人密度的关系.模型成功再现通道内双向行人流的编队成行及相变现象.

关键词：双向行人流微观仿真双层协作多智能体

Plant distribution and pharmacological activity of flavonoids

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Traditional Medicine Research 2019年第5期4卷 269-287页

作者： shao-Hui Wang Yan-Lan Hu tong-Xiang Liu Medical College Qingdao Binhai University Qingdao 266555 China Affiliated Hospital of Qingdao Binhai University Qingdao 266555 China Key Laboratory of Ethnomedicine (Minzu University of China) Ministry of Education Beijing 100081 China School of Pharmacy Minzu University of China Beijing 100081 China

Flavonoids are natural organic compounds that are widely found in nature, their structural types are complex, and they mainly include flavonoids, flavonols, dihydroflavonols, isoflavones, dihydroisoflavones, chalcones, orange ketones, flavanoids, anthocyanidins, and biflavonoids. This review covers the plant distribution and pharmacological activities of flavonoids. Flavonoids are mainly distributed in angiosperms and gymnosperms, and they are abundant in plants such as Rutaceae, Labiatae, Zingiberaceae, Scrophulariaceae, and Leguminosae. Because of their wide distribution and variety, researchers have found that flavonoids have diverse biological activities, mainly focusing on anti-inflammatory, antibacterial and antitumor activities. Mechanistically, the anti-inflammatory effects are mainly related to the NF-κB and MAPK (mitogen-activated protein kinase) signaling pathway and then the inhibition of the production of inflammatory cytokines and mediators. The antibacterial activity is mainly manifested as inhibitory effects on many strains, including Escherichia coli, Cryptococcus neoformans, and Pseudomonas aeruginosa, via destroying the stability of the microbial membrane, inhibiting the invasion of virulent bacteria into host cells, promoting the apoptosis of bacteria, inhibiting bacterial fatty acid synthesis, etc. The antitumor activity of flavonoids is related to their inhibition of cell proliferation and induction of apoptosis via the mitochondria-mediated, endoplasmic reticulum-mediated, and death factor and its receptor-mediated signal transduction pathways. Understanding the plant distribution and pharmacological activity of flavonoids not only reveals the importance of identifying such valuable flavonoids in another genus or family but also provides a basis for fully exploiting the therapeutic potential of flavonoids.

关键词： Flavonoids Plant distribution Pharmacological activity Antitumor Anti-inflammatory Antibacterial

模拟快递运输对雌性中华绒螯蟹活力及其蟹肉品质的影响

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渔业科学进展 2024年第1期45卷 234-245页

作者：肖童丁威卢祺郭学骞尹明雨王锡昌上海海洋大学食品学院上海201306 上海水产品加工及贮藏工程技术研究中心上海201306 农业农村部水产品贮藏保鲜质量安全风险评估实验室上海201306

探究雌性中华绒螯蟹(Eriocheir sinensis)在运输过程中活力、生化特性和滋味品质的变化,并分析三者之间的相关性。通过模拟电商生鲜运输条件,对模拟快递运输24 h、48 h和72 h的中华绒螯蟹活力进行统计和评价,以乳酸、挥发性盐基氮(TVB-N... 详细信息

探究雌性中华绒螯蟹(Eriocheir sinensis)在运输过程中活力、生化特性和滋味品质的变化,并分析三者之间的相关性。通过模拟电商生鲜运输条件,对模拟快递运输24 h、48 h和72 h的中华绒螯蟹活力进行统计和评价,以乳酸、挥发性盐基氮(TVB-N)和pH等分析中华绒螯蟹蟹肉生化特性的变化,同时以游离氨基酸、呈味核苷酸及感官等评价中华绒螯蟹蟹肉滋味品质的变化。结果显示,中华绒螯蟹在24 h的模拟运输下,无死亡且活力强劲,蟹肉乳酸和TVB-N等与0 h组无显著差异,且24 h组蟹肉的苦味氨基酸含量最低,为105.10 mg/100 g,印证了活蟹当日送达的重要性。超过24 h后,中华绒螯蟹的活力显著下降,死亡率上升,其中,模拟运输48 h后死亡率为3.33%,72h后死亡率达40.00%;其蟹肉乳酸、TVB-N及pH显著升高;随着运输时间的延长,蟹肉鲜、甜、苦味游离氨基酸含量均呈先下降后上升的趋势,而在模拟运输72 h后,5′-肌苷酸(IMP)含量显著增加至97.47 mg/100 g,5′-鸟苷酸(GMP)含量骤降至6.49 mg/100 g。感官结果则表明,经过模拟快递运输后,蟹肉的鲜味强度降低。综上所述,随着运输时间的延长,雌性中华绒螯蟹的死亡率显著上升,活力显著下降,生化特性和滋味品质发生显著改变,本研究可为销售运输过程中中华绒螯蟹的品质变化提供参考,并为后续运输条件优化提供理论依据。

关键词：中华绒螯蟹模拟快递运输活力生化特性滋味品质

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倾向性评分逆概率加权中极端权重处理方法的模拟比较及应用研究

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中华疾病控制杂志 2024年第1期28卷 69-74页

作者：许毛毛高绒绒高倩王菊平王佳乐王彤山西医科大学公共卫生学院卫生统计学教研室煤炭环境致病与防治教育部重点实验室太原030001

目的通过模拟研究比较倾向性评分逆概率加权法(inverse probability weighting,IPW)及其5种替代方法在有限重叠和倾向评分模型错误指定下的性能,并应用这些方法探讨血清总25-羟基维生素D[25⁃hydroxyvitamin D,25(OH)D]缺乏与成年人睡眠... 详细信息

目的通过模拟研究比较倾向性评分逆概率加权法(inverse probability weighting,IPW)及其5种替代方法在有限重叠和倾向评分模型错误指定下的性能,并应用这些方法探讨血清总25-羟基维生素D[25⁃hydroxyvitamin D,25(OH)D]缺乏与成年人睡眠时间的关系。方法通过蒙特卡洛模拟,设置不同样本量、倾向性评分重叠度、模型指定情况的模拟场景,比较6种方法的统计性能。结果模拟结果显示,IPW对重叠度差和模型错误指定比较敏感,其替代方法可表现出更强的稳定性和更高的效率,其中重叠权重(overlap weights,OW)法可提供最好的效应估计。血清总25(OH)D缺乏者睡眠时间比血清总25(OH)D充足者少(P<0.001)。结论OW可作为存在极端权重时IPW方法的最优替代,血清总25(OH)D缺乏会减少成年人的睡眠时间。

关键词：倾向性评分逆概率加权极端权重 25-羟基维生素D 睡眠时间

Near-infrared fluorescent probes for imaging of amyloid plaques in Alzheimer's disease

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Acta Pharmaceutica Sinica B 2015年第1期5卷 25-33页

作者： Hongjuan tong Kaiyan Lou Wei Wang Shanghai Key Laboratory of Chemical Biology School of Pharmacy State Key Laboratory of Bioengineering ReactorEast China University of Science and Technology Department of Chemistry and Chemical Biology University of New Mexico

One of the early pathological hallmarks of Alzheimer's disease(AD) is the deposition of amyloid-β(Aβ) plaques in the brain. There has been a tremendous interest in the development of Aβ plaques imaging probes for early diagnosis of AD in the past decades. Optical imaging, particularly near-infrared fluorescence(NIRF) imaging, has emerged as a safe, low cost, real-time, and widely available technique, providing an attractive approach for in vivo detection of Aβ plaques among many different imaging techniques. In this review,we provide a brief overview of the state-of-the-art development of NIRF Aβ probes and their in vitro and in vivo applications with special focus on design strategies and optical, binding, and brain-kinetic properties.

关键词： Alzheimer’s disease Blood-brain barrier Fluorescence probe Near-infrared fluorescence Optical imaging Amyloid-β plagues

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疫苗素养评价工具研究进展

预防医学 2024年第9期36卷 768-771页

作者：王苗玲(综述) 童莺歌(审校) 杭州师范大学护理学院浙江杭州311121

疫苗素养关系着居民对疫苗相关信息和服务的获取和使用情况,提升居民疫苗素养可增强疫苗信心,减少疫苗犹豫,提高接种依从性。开展疫苗素养评价工作有助于了解居民对疫苗的认知和态度,为明确疫苗素养影响因素、探寻疫苗素养提升路径提供... 详细信息

疫苗素养关系着居民对疫苗相关信息和服务的获取和使用情况,提升居民疫苗素养可增强疫苗信心,减少疫苗犹豫,提高接种依从性。开展疫苗素养评价工作有助于了解居民对疫苗的认知和态度,为明确疫苗素养影响因素、探寻疫苗素养提升路径提供参考。本文通过检索疫苗素养评价相关的研究文献,获取人乳头瘤病毒疫苗素养调查问卷、疫苗丑闻相关素养问题、意大利成人疫苗素养量表、新型冠状病毒疫苗素养量表、疫苗健康素养测量工具、数字疫苗素养量表、中文版新型冠状病毒疫苗素养量表和社区居民疫苗素养量表等8项疫苗素养评价工具,从评价对象、内容、信效度和应用等方面进行综述,为我国开展居民疫苗素养评价工作提供对策建议。

关键词：疫苗素养评价工具疫苗接种健康素养

“沉积岩石学”课程思政建设与探索——以中国石油大学(北京)为例

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中国地质教育 2024年第2期33卷 80-84页

作者：朱世发佟欢高艺珊中国石油大学(北京)地球科学学院北京102249

“沉积岩石学”作为地质类专业学生的一门核心必修课程,承担着培养高素质创新型地学人才的责任和使命。秉承党中央强调的“把思政工作贯穿教育教学全过程”理念,文章以中国石油大学(北京)“沉积岩石学”课程为例,通过挖掘思政元素、探... 详细信息

“沉积岩石学”作为地质类专业学生的一门核心必修课程,承担着培养高素质创新型地学人才的责任和使命。秉承党中央强调的“把思政工作贯穿教育教学全过程”理念,文章以中国石油大学(北京)“沉积岩石学”课程为例,通过挖掘思政元素、探索融入策略、设计教学考核三大步骤,从人文教育、环保教育、地质灾害科普教育三个方面着手,致力于专业知识传授与思想政治教育双重育人效果,为切实开展地质专业课程思政教学奠定坚实的基础。

关键词：沉积岩石学课程思政教学案例

Effects of gully terrain on stress field distribution and ground pressure behavior in shallow seam mining

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International Journal of Mining Science and Technology 2016年第2期26卷 255-260页

作者： Li Jianwei Liu Changyou Zhao tong School of Mines China University of Mining & Technology Key Laboratory of Deep Coal Resource Mining Ministry of Education China University of Mining & Technology

This study proposes a novel approach to study stress field distribution and overlying ground pressure behavior in shallow seam mining in gully *** approach combines numerical simulations and field tests based on the conditions of gully terrain in the Chuancao Gedan *** effects of gully terrain on the in situ stress field of coal beds can be identified by the ratio of self-weight stress to vertical stress(η) at the location corresponding to the maximum vertical *** on the function η =j(h),the effect of gully terrain on the stress field of overlying strata of the entire field can be characterized as a significantly affected area,moderately affected area,or non-affected *** face 6106 in the Chuancao Gedan Mine had a coal bed Jepth <80 m and was located in what was identified as a significantly affected ***,mining may cause sliding of the gully slope and increased loading(including significant dynamic loading) on the roof *** tests suggest that significant dynamic pressures were observed at the body and foot of the gully slope,and that dynamic loadings were observed upslope of the working face expansion,provided that the expanding direction of the working face is parallel to the gully.

关键词： Gully terrain Shallow seam Stress field Slope motion Ground pressure behavior

Oviposition preference, larval performance and adaptation of Trichoplusia ni on cabbage and cotton

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Insect Science 2015年第2期22卷 273-282页

作者： Yuan-Xi Li tong-Xian Liu Department of Entomology College of Plant Protection Nanjing Agricultural University Nanjing State Key Laboratory of Crop Stress Biology for Arid Areas and Key Laboratory of Crop IPM for the Loess Plateau Ministry of Agriculture of China at Northwest A&F University Yangling Shaanxi China

Most female herbivores ensure to lay eggs where their offspring can develop successfully. The oviposition preferences of females affect strategies in pest management. In this study, the performance of two cohorts of Trichoplusia ni larvae on cabbage and cotton （after they had been transferred from their original host plants） were investigated. The preferences of female moth ovipositing and larval feeding on these two host plants were observed. The results indicated that plants significantly affected oviposition preference of the female adults and development and survival of larvae of T. ni. All females preferred to lay eggs on cabbage than cotton regardless from which host they originated. The detrimental effects of cotton on the development and survival of T. ni larvae originated from cabbage （CaTn） increased with the increase of the larval age when they were transferred. In addition, the host plant change did not significantly affect the development and survival of larvae of T. ni originating from cotton （CoTn）. Larvae of CaTn preferred cabbage plants as compared to cotton plants, whereas larvae of CoTn did not show a significant choice. Although the adult females preferred laying eggs on cabbage, they did not show preferences between cotton and cabbage in a Y-tube olfactometer test. The hypothesis of oviposition preference and performance of larvae was supported by the results of CaTn, whereas they not supported by those from CoTn. Based on these results, the strategy to manage this serious pest was discussed.

关键词： cabbage looper development larval choice oviposition preference