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Prospects of sea buckthorn(Hippophae rhamnoides L.) polysaccharides: preparation， structural characterization， and bioactivities diversity

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Food Science and Human Wellness 2024年

作者： shuyuan shi Ruiyun Wu Zixin Han Yu Sun Pinglan Li Fazheng Ren Nan Shang Key Laboratory of Precision Nutrition and Food Quality College of Food Science and Nutritional Engineering China Agricultural University Key Laboratory of Precision Nutrition and Food Quality Department of Nutrition and Healthy China Agricultural University College of Engineering China Agricultural University

Sea buckthorn (Hippophae rhamnoides L.) is a natural homologous substance of medicine and food. Polysaccharide， as one of its primary active components， has very superior biological activity and can be used as a dietary supplement for functional foods， with good commercial prospects. Although initial progress has been made in the study of sea buckthorn polysaccharides， related studies have been fragmented and lacked systematic and generalization. This manuscript presents a critical analysis and systematic summary of the extraction and purification methods， structural characterization and physicochemical properties， biological activity and potential mechanisms， and structure-activity relationships of sea buckthorn polysaccharides. Accumulating evidence has indicated that sea buckthorn polysaccharides， which were widely prepared by water extraction and column chromatography purifications， exhibited exhibit superior biological activities in vitro and in vivo， including antioxidant， immunomodulatory， anti-inflammatory， hepatorenal protective， antibacterial， antiviral， and prebiotic activities. After analysis， it was concluded that there is a correlation between the relevant activities of sea buckthorn polysaccharides and that the structure of sea buckthorn polysaccharides has a great influence on their biological activity. We reviewed the challenges and limitations of sea buckthorn polysaccharides， summarized the critical aspects， and provided suggestions for potential breakthroughs in the research and application of sea buckthorn polysaccharide.

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Bitumen formation of Cambrian Longwangmiao Formation in the central Sichuan and its implication for hydrocarbon accumulation

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Petroleum Research 2018年第1期3卷 44-56页

作者： Bin Hao Wenzhi Zhao Suyun Hu shuyuan shi Ping Gao Tongshan Wang shipeng Huang Hua Jiang Northwest Branch PetroChina Research Institute of Petroleum Exploration and DevelopmentGansu 730020China PetroChina Research Institute of Petroleum Exploration and Development Beijing 100083China Sinopec Petroleum Exploration and Production Research Institute Beijing 100083China

Based on organic petrology,organic geochemistry and SEM method,type,formation period and source of bitumens in the Cambrian Longwangmiao Formation in the central Sichuan Basin were well investigated,and combined with fluid inclusions and tectonic evolution characteristics,the hydrocarbon accumulation history of the gas reservoir of the Longwangmiao Formation in the Anyue gasfield was also studied.The result shows that all bitumens in the Longwangmiao Formation was from the Lower Cambrian source rocks,it had multiple genetic types which was dominated by the pyrolysis genetic type;the bitumens were formed into three stages,i.e.,the bitumen of the oxidized water-washing type in the first stage,the bitumen of the precipitated type in the second stage,and the bitumen of the pyrolyzed type in the third stage;the gas reservoir in the Anyue gasfield experienced five stages of hydrocarbon charging,including two stages of liquid hydrocarbon charging,charging of the kerogen pyrolysis gas in the Late Triassic-Early Jurassic,charging of the crude oil pyrolysis gas in the Late Jurassic-Early Cretaceous and charging of the dry gas charging in the Himalayan trap reformation and adjustment process.

关键词： Bitumen Biomarker Authigenic minerals Inclusion Hydrocarbon charging Longwangmiao Formation Central Sichuan

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Image analysis considering textual correlations enables accurate user switching tendency prediction

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Optoelectronics Letters 2023年第8期19卷 498-505页

作者： WANG Jianbin shi shuyuan WANG Xuna YU Jiahui Zhejiang University Hangzhou 310027China China Telecom Zhejiang Branch Hangzhou 310014China School of Automation and Electrical Engineering Shenyang Ligong UniversityShenyang 110159China School of Computing University of PortsmouthPortsmouth PO13HEUK

Predicting likely-to-churn users employing surveys is a challenging task.Individuals with different personalities may make different choices in the same situation,so we introduced social media avatars that reflect the user’s psychological state when analyzing their churn tendency.In this paper,we propose a multimodal framework that jointly learns image and text features to establish correlations among users with low net promoter score(NPS) and those likely to churn.We conducted experiments on actual data,and the results show that our proposed method can identify NPS-degraded users in advance,promoting the commercial development of the operator.

关键词： Image likely enable

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塔里木盆地肖尔布拉克组上段烃源岩分布预测及油气勘探意义

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地学前缘 2024年第2期31卷 343-358页

作者：徐兆辉胡素云曾洪流马德波罗平胡再元石书缘陈秀艳陶小晚中国石油勘探开发研究院北京100083 美国得克萨斯大学奥斯汀分校经济地质局美国奥斯汀787133 中国石油勘探开发研究院西北分院甘肃兰州730020

通常认为塔里木盆地下古生界海相烃源岩以下寒武统玉尔吐斯组泥质岩为主、中下奥陶统泥质岩为辅,下寒武统肖尔布拉克组上段(肖上段)以白云岩储层为主。塔中和塔北地区均钻遇了肖上段泥灰岩,最近钻探的京能柯探1和轮探3井肖上段泥灰岩样... 详细信息

通常认为塔里木盆地下古生界海相烃源岩以下寒武统玉尔吐斯组泥质岩为主、中下奥陶统泥质岩为辅,下寒武统肖尔布拉克组上段(肖上段)以白云岩储层为主。塔中和塔北地区均钻遇了肖上段泥灰岩,最近钻探的京能柯探1和轮探3井肖上段泥灰岩样品TOC含量多数>0.3%,少量>2%。盆地内不同地区五口井肖上段发育泥灰(云)岩烃源岩,与苏盖特布拉克露头肖上段暗色泥灰岩地化指标(TOC含量是0.41%、R o是1.14%)一致,表明肖上段泥灰岩具备生烃能力。本文基于露头、地震和钻测井资料,利用地震沉积学理论技术、属性与正演相结合,建立了肖上段台内多期叠置“礁滩源”沉积模式。发现烃源岩分布在礁前至坡脚变缓处,连片分布广、叠合厚度大,是规模有效烃源岩,可为邻近储层供烃。经测算,古城三维区肖上段泥灰岩烃源岩总生烃量超亿吨。研究认识拓展了塔里木盆地下古生界海相烃源岩类型、层系和分布范围,提升了寒武系盐下油气资源潜力,坚定了勘探重点从台缘带向台内战略转移的信心,为塔里木盆地古城地区乃至全盆地油气勘探带来新启示。

关键词：塔里木盆地肖尔布拉克组上段泥灰岩烃源岩地震沉积学油气勘探意义

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深层古老碳酸盐岩-膏盐岩组合油气成藏特征

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石油勘探与开发 2024年第1期51卷 48-61页

作者：石书缘胡素云刘伟王铜山周刚徐安娜黄擎宇徐兆辉郝彬王坤姜华马奎白壮壮中国石油勘探开发研究院北京100083 中国石油西南油气田公司勘探开发研究院成都610041 中国石油勘探开发研究院西北分院兰州730020

通过分析塔里木、四川和鄂尔多斯三大海相盆地埃迪卡拉系—奥陶系,并对比参考东西伯利亚、阿曼和澳大利亚Officer三大国外盆地新元古界—寒武系的地层特征,将碳酸盐岩-膏盐岩组合划分成碳酸盐岩类和膏盐岩类互为夹层型、碳酸盐岩类和膏... 详细信息

通过分析塔里木、四川和鄂尔多斯三大海相盆地埃迪卡拉系—奥陶系,并对比参考东西伯利亚、阿曼和澳大利亚Officer三大国外盆地新元古界—寒武系的地层特征,将碳酸盐岩-膏盐岩组合划分成碳酸盐岩类和膏盐岩类互为夹层型、碳酸盐岩类和膏盐岩类互层型以及碳酸盐岩类、膏盐岩类和碎屑岩类共生型3种类型,明确了碳酸盐岩-膏盐岩组合的概念及内涵。结果表明:(1)碳酸盐岩-膏盐岩组合的油气通常来源于泥页岩和泥质碳酸盐岩两类烃源岩,咸化环境膏盐岩可促进烃源岩生烃。(2)主要发育膏云坪型、颗粒滩和微生物丘型两大类白云岩储集层,准同生期或表生期的大气淡水淋滤是储集层规模发育的主要控制因素,后期埋藏溶蚀作用对储集层有调整和改造作用。(3)碳酸盐岩-膏盐岩组合油气成藏模式可划分为盐下成藏模式、盐上成藏模式和盐间成藏模式3大类8小类模式。塔里木盆地塔中隆起北坡、麦盖提斜坡和玛扎塔格前缘隆起带寒武系、四川盆地东部—南部地区寒武系和鄂尔多斯盆地奥陶系盐间马家沟组四段等为未来的有利勘探领域。

关键词：碳酸盐岩-膏盐岩组合白云岩储集层烃源岩油气成藏四川盆地塔里木盆地鄂尔多斯盆地

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临床干预措施效力-效果差距弥合的方法学研究进展(一):改善真实世界研究的效果估计

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中华流行病学杂志 2024年第4期45卷 286-293页

作者：刘佐相龙子临杨智荣石舒原许欣然赵厚宇杨祖耀符祝宋海波林腾飞詹思延孙凤北京大学公共卫生学院流行病与卫生统计学系北京100191 重大疾病流行病学教育部重点实验室(北京大学) 北京100191 中国科学院深圳先进技术研究院计算机科学与控制工程学院深圳518055 中国康复科学所/中国残疾人联合会残疾预防与控制中心北京100068 香港中文大学公共卫生及基层医疗学院中国香港999077 海南省博鳌乐城国际医疗旅游先行区管理局海南省真实世界数据研究院海口571437 国家药品监督管理局药品评价中心中药监测和评价部北京100076 国家药品监督管理局药物警戒研究与评价重点实验室北京100076 中国科学院深圳先进技术研究院先进计算与数字工程研究所生物医学信息技术研究中心深圳518055 北京大学第三医院临床流行病学研究中心北京100191

目的干预措施在临床实践中的实际干预效果与随机对照试验(RCT)中表现的效力存在差异,即效力-效果差距。RCT结果与真实世界研究(RWS)结果的差异可能无法代表真实的效力-效果差距,这是因为当RWS与RCT在研究设计上有较大差异,或RWS结果估... 详细信息

目的干预措施在临床实践中的实际干预效果与随机对照试验(RCT)中表现的效力存在差异,即效力-效果差距。RCT结果与真实世界研究(RWS)结果的差异可能无法代表真实的效力-效果差距,这是因为当RWS与RCT在研究设计上有较大差异,或RWS结果估计存在偏倚时,效力-效果的估计可能是有偏的。其次,当发现干预措施存在效力-效果差距,不能对所有患者实行一刀切的临床决策,而需要进一步评估影响干预措施效果的真实世界因素,识别可能取得期望效用的患者群体。方法检索PubMed、Embase、Web of Science、万方数据知识服务平台、维普数据库、中国知网6个数据库从建库至2022年12月31日的中英文文献,采用概括性综述的方法,对如何改进RWS设计从而弥合效力-效果差距的方法进行归纳整合和定性描述。结果共纳入10篇文献,探讨如何以RCT研究方案为模板,制定相应的RWS方案,在正确估计效力-效果差距的基础上,进一步评估干预措施在患者亚群中的效果,选取能获得预期收益风险比的患者亚群,从而弥合效力-效果差距。结论使用医疗大数据,模拟目标试验方案关键特征,可以提高研究结果的真实性和有效性,弥合效力-效果差距。

关键词：随机对照试验真实世界证据目标试验效力效果

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Depositional System of the Carboniferous Huanglong Formation,Eastern Sichuan Basin:Constraints from Sedimentology and Geochemistry

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Acta Geologica Sinica(English Edition) 2016年第5期90卷 1795-1808页

作者： WANG Kun HU Suyun LI Wei LIU Wei HUANG Qingyu MA Kui shi shuyuan Research Institute of Petroleum Exploration and Development CNPC

Using analyses of the lithology,sequences,paleoenvironment,and tectonic setting,the depositional system of the Carboniferous Huanglong Formation in the eastern Sichuan Basin was identified.The lithological characteristics of the Lower Member,Middle Member,and Upper Member were analyzed and classified.Before the use of carbon,oxygen,and strontium isotopes in the analysis,all of the geochemical data were tested for validity.On the basis of the Z values obtained from carbon and oxygen isotopes,the paleoenvironments of the three members were elucidated.Lower Member was dominantly an enclosed marine environment with intense evaporation and little freshwater input into the sea.Middle Member developed in a semi-enclosed to normal marine environment with many rivers.Upper Member was formed in a normal marine environment.The east Sichuan Basin was enclosed by paleouplifts before the deposition of the Huanglong Formation,forming a relatively enclosed depositional setting.Paleogullies developed in the Silurian strata that underlie the Carboniferous rocks;these paleogullies can be identified.On the basis of a comprehensive analysis,we propose that the Huanglong Formation developed in a platform system.Four microfacies were identified：supratidal flat,dolostone flat,grain shoal,and shelf microfacies.The high-permeability and high-porosity characteristics of the grain shoal microfacies are favorable for hydrocarbon accumulation,while the supratidal flat and shelf microfacies developed very few high-quality reservoirs.The paleogullies,in which increased amounts of grain shoal microfacies developed,controlled the distribution of high-quality reservoirs.

关键词： eastern Sichuan Basin Huanglong Formation depositional system paleoenvironment paleogully reservoir quality

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Tectonic paleogeography of Late Sinian and its significances for petroleum exploration in the middle-upper Yangtze region, South China

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Petroleum Exploration and Development 2020年第5期47卷 946-961页

作者： WANG Zecheng JIANG Hua CHEN Zhiyong LIU Jingjiang MA Kui LI Wenzheng XIE Wuren JIANG Qingchun ZHAI Xiufen shi shuyuan LI Qi PetroChina Research Institute of Petroleum Exploration&Development Beijing 100083China PetroChina Southwest Oil&Gas Field Company Chengdu 610051China PetroChina Hangzhou Research Institute of Geology(HIPG) Xihu DistrictHangzhou 310023China

The paleotectonic pattern,lithofacies paleogeographic features,sedimentary evolution and its controlling effects on hydrocarbon accumulation assemblages during the depositional period of the Sinian Dengying Formation in middle-upper Yangtze region were investigated based on outcrops,drilling,log and seismic data.The study shows that,(1)Affected by the breakup of the Rodinia supercontinent,the middle and upper Yangtze areas were in extensional tectonic environment during the depositional period of Dengying Formation.The carbonate platform was structurally differentiated.Intra-platform depressions controlled by syndepositional faults developed,forming a tectonic-paleogeographic pattern of"three platforms with two depressions".(2)During the depositional period of the first and second members of the Dengying Formation,rimmed platforms and intra-platform fault depressions developed in upper Yangtze area and isolated platform developed in middle Yangtze area,and there was the Xuanhan-Kaijiang ancient land block in eastern Sichuan.The depositional period of the third member of the Dengying Formation is the transformation period of tectonic-paleogeographic pattern,when a set of shallow water shelf sediment rich in mud was deposited due to transgression on the background of the eroded terrain formed in EpisodeⅠof Tongwan Movement.The sediment of the fourth member of the Dengying Formation inherited the paleogeographic pattern of the first and second members of the Dengying Formation in general,but the Deyang-Anyue intra-platform fault depression further expanded,and the middle Yangtze platform evolved into two separated platforms.(3)Tectonic-sedimentary differentiation and evolution of carbonate platform in the Sinian gave rise to two types of accumulation assemblages with wide distribution and great exploration potential,which are platform margin and intra-platform.

关键词： tectonic paleogeography structural differentiation intra-platform fault depression rimmed platform microbial mounds and shoals Sinian Dengying Formation Sichuan Basin the middle-upper Yangtze region

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The spectrum of rare monogenic diseases in patients with premature coronary artery disease

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中华医学杂志(英文版) 2024年第10期137卷 1246-1248页

作者： Teng Yaqun Du Tian Feng Siqin Tian Ran Liu Yaping Guo Jian Wang Lei Zhang Zhiyu Luan Xiaodong He Shan Zhuang Shengsheng Wang Yifei Zhang shuyuan Chen shi Liu Zhenyu Zhang Shuyang Department of Cardiology State Key Laboratory of Complex Severe and Rare disease Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing China Department of Internal Medicine Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing China Department of Basic Medical Sciences Tsinghua University School of Medicine Beijing China Department of Breast Oncology Sun Yat-sen University Cancer Center Guangzhou Guangdong China McKusick-Zhang Center for Genetic Medicine State Key Laboratory of Medical Molecular Biology Institute of Basic Medical Sciences Chinese Academy of Medical Sciences School of Basic Medicine Peking Union Medical College Beijing China Tsinghua University-Peking University Joint Center for Life Sciences Beijing China Department of Cardiology Beijing Tsinghua Changgung Hospital Tsinghua University Beijing China Department of Endocrinology Key Laboratory of Endocrinology of National Health Commission Peking Union Medical College Hospital Chinese Research Center for Behavior Medicine in Growth and Development Beijing China

The global burden of premature coronary artery disease (CAD) is increasing among the young population. Premature CAD generally refers to the occurrence of obstructive coronary atherothrombotic lesions in men and women aged <55 years and <65 years, respectively, and particularly in those aged <45 years.[1] The incidence of CAD in the younger population has remained stable or has increased, despite the declining incidence in older adults. Patients with premature CAD have a poor long-term prognosis, experiencing a high rate of recurrent ischemic events, rapid progression to multivessel disease, and frequent premature death.[1] Thus, it is crucial to identify the underlying causes of premature CAD that are distinct from those of age-related CAD and improve patient outcomes through precise diagnosis and treatment.

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TiO_(2)/有机硅溶胶改性含氟苯丙乳液的制备及性能表征

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材料导报 2023年第8期37卷 234-241页

作者：史书源安秋凤邱甲云陕西科技大学化学与化工学院陕西省轻化工助剂重点实验室西安710021

为改善含氟苯丙乳液的疏水性、热稳定性及力学性能,以钛酸丁酯(TBT)、γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH-570)为原料,通过溶胶-凝胶法制备出TiO_(2)/有机硅溶胶(TS),并将其与丙烯酸丁酯(BA)、苯乙烯(ST)、甲基丙烯酸十二氟庚酯(G04... 详细信息

为改善含氟苯丙乳液的疏水性、热稳定性及力学性能,以钛酸丁酯(TBT)、γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH-570)为原料,通过溶胶-凝胶法制备出TiO_(2)/有机硅溶胶(TS),并将其与丙烯酸丁酯(BA)、苯乙烯(ST)、甲基丙烯酸十二氟庚酯(G04)及其他丙烯酸类功能单体作为主要原料,通过半连续加料法及种子乳液聚合,制备出一种TiO_(2)/有机硅溶胶改性的含氟苯丙乳液(TS-BHSAG)。探讨了不同TS含量对乳液转化率的影响,利用FTIR、纳米粒度仪、稳定性分析仪、XPS、XRD、SEM、AFM、TGA表征研究了乳液及乳胶膜的结构组成及应用性能。结果表明,当TS含量逐渐增加时,乳液转化率及稳定性呈持续下降趋势;随着TS含量增加,乳液平均粒径从55.58 nm增至106.16 nm;FTIR及XPS结果显示,TS-BHSAG乳胶膜中形成了Si-O-Si、Si-O-Ti、CF2键,证实TS被初步合成,且其与G04一起被引入聚合物中;XRD结果表明,TS是以无定形相分散于丙烯酸树脂基体中;通过SEM与AFM观察到,TS纳米粒子在乳胶膜表面构成峰状粗糙结构,增强了乳液的疏水性能;TGA结果表明,在热失重为10%及50%时,TS-BHSAG的热分解温度分别为380.59℃、415.39℃,在600℃时,乳胶膜的残余质量分数从4.78%增加到8.56%;当TS添加量为3%时,TS-BHSAG乳胶膜的接触角为121°,附着力为1级,耐冲击性能为50 cm,硬度为2H,吸水率为6.1%。

关键词： TiO_(2)/有机硅改性乳液聚合含氟苯丙乳液疏水性热稳定性

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