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不同磁共振成像技术在急性脑梗死动脉血栓患者中的诊断及预后的应用价值

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实用医学影像杂志 2024年第2期25卷 128-131页

作者：卢思奇江西省新余钢铁集团有限公司中心医院放射科 338001

目的探讨急性脑梗死动脉血栓患者采用不同磁共振成像(MRI)的疾病检出率及预后情况。方法将79例急性脑梗死动脉血栓患者纳入为研究对象,患者入组时间均为2021年9月至2022年9月,所有入组患者均接受常规MRI扫描、磁敏感加权成像(SWI)及... 详细信息

目的探讨急性脑梗死动脉血栓患者采用不同磁共振成像(MRI)的疾病检出率及预后情况。方法将79例急性脑梗死动脉血栓患者纳入为研究对象,患者入组时间均为2021年9月至2022年9月,所有入组患者均接受常规MRI扫描、磁敏感加权成像(SWI)及弥散加权成像(DWI),将入组患者按照血栓负荷评分(CBS)分为A组(≤5分,15例)、B组(6~9分,30例)、C组(10分,34例)。分析常规MRI的SWI、DWI序列下对急性脑梗死动脉血栓诊出率;比较不同组别患者美国国立卫生研究院卒中量表(NIHSS)评分情况;比较不同组别患者随访的预后情况。结果 SWI对急性脑梗死动脉血栓诊出率为91%(72/79),均高于常规MRI、DWI的79%(62/79)、80%(63/79);A组患者的NIHSS评分为36.4±3.8分,B组患者的NIHSS评分为30.4±3.5分,C组患者的NIHSS评分24.6±3.0分,C组患者的评分低于B组,且B组低于A组;C组患者预后良好情况为91%(31/34),均高于A组、B组的80%(12/15)、83%(25/30)(P<0.05)。结论急性脑梗死动脉血栓患者采用SWI的疾病检出率更高,患者的CBS评分越低,神经缺损越严重,预后情况越差。

关键词：脑梗死急性动脉血栓磁共振成像诊断预后

Promoting the methanol oxidation catalytic activity by introducing surface nickel on platinum nanoparticles

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Nano Research 2018年第4期11卷 2058-2068页

作者： siqi lu Huiming Li Jingyao Sun Zhongbin Zhuang State Key Lab of Organic-Inorganic Composites Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing Key Lab of Energy Environmental Catalysis Beijing University of Chemical Technology Beijing 100029 China

High performance methanol oxidation reaction （MOR） catalysts are critical to the performance of attractive, direct methanol fuel cells. Here, we use surface controlled PtNi alloy nanoparticles as model catalysts to study the MOR mechanism and give further guidance to the design of new high performance MOR catalysts. The enhanced MOR activity of PtNi alloy was mainly attributed to the enhanced OH adsorption owing to surface Ni sites. This suggests that the MOR undergoes the Langmuir-Hinshelwood mechanism, whereby adsorbed CO is removed with the assistance of adsorbed OH. Within the PtNi catalyst, Pt provides methanol adsorption sites （in which methanol is converted to adsorbed CO） and Ni provides OH adsorption sites. The optimized Pt-Ni ratio for MOR was found to be 1：1. This suggests that bifunctional catalysts with both CO and OH adsorption sites can lead to highly active MOR catalysts.

关键词： methanol oxidation reaction (MOR) Pt alloy catalysts surface structure OH adsorption

A survey on cryptographic techniques for protecting big data security: present and forthcoming

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Science China(Information Sciences) 2022年第10期65卷 73-106页

作者： siqi lu Jianhua ZHENG Zhenfu CAO Yongjuan WANG Chunxiang GU School of Cyberspace Security Information Engineering University Henan Key Laboratory of Network Cryptography Technology Institute of Security Technology Shanghai Key Laboratory of Trustworthy Computing East China Normal University Cyberspace Security Research Center Peng Cheng Laboratory Shanghai Institute of Intelligent Science and Technology Tongji University

Big data drive multidimensional convergence and profound innovations among industries and provide novel ways of exploring the world. As they significantly create economic and social value, big data meaningfully impact the implementation and management of information security and privacy *** technologies are used to protect the security and entire life cycle of big data. The demand for this technology is multiplied when the data are stored in the cloud. They are stored in the cloud in the form of ciphertext, and the driving requirement for data retrieval, sharing, and manipulation places the security of data at risk. The all-or-nothing approach of traditional cryptography systems cannot realize the release and processing of data information with flexible and increasingly fine granularity. Consequently, dealing with the relationship between privacy protection and data utilization, as well as navigating the blurry boundaries between subverting either plaintext or ciphertext, has become a research focus of the current cryptographic trend for protecting big data security. Presently, there are many studies designed to solve these ***, security requirements and source encryption mode for future big data systems and applications are elaborated. Then, focusing on the practical security and functionality of the big data life cycle, including storage, retrieval, sharing, calculation, statistical analysis, and utilization, the research being conducted based on those functions is reviewed. For each cryptographic technology that meets the requirement of each type of big data security or application, security and efficiency comments and sufficient comparison analyses of cryptography schemes or protocols are provided; moreover, the current general problems and development trends are expounded. Because the current innovative research on cryptographic technology was primarily based on the development or improvement of a single solution, the study on

关键词： big data security cryptographic techniques ciphertext-based data sharing and computing authenticated encryption functional encryption homomorphic encryption secure multi-party computing

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贵州省三都县滑坡特征及分布规律研究

地质与勘探 2024年第4期60卷 830-837页

作者：兰中孝张才兵杨雲兵卢思其王源夏江黔丁金英贵州地矿基础工程有限公司贵州贵阳550081 贵州省地质调查院贵州贵阳550081

为提高贵州省三都县地质灾害的防灾减灾能力,通过资料收集、地质灾害调查、数理统计、GIS空间分析等手段,查明了研究区滑坡数量及特征,研究了滑坡与地质构造、工程地质岩组、斜坡结构、坡度、坡形和人类工程活动等孕灾因子的关系,总结... 详细信息

为提高贵州省三都县地质灾害的防灾减灾能力,通过资料收集、地质灾害调查、数理统计、GIS空间分析等手段,查明了研究区滑坡数量及特征,研究了滑坡与地质构造、工程地质岩组、斜坡结构、坡度、坡形和人类工程活动等孕灾因子的关系,总结该县滑坡发育特征与分布规律。结果表明:研究区共发育滑坡57处,多发育在坡度20°~30°范围内,相对高差主要在20~40 m之间,坡形以凸形坡为主。在地质构造方面,丰乐断层、大河断层、烂土断层影响较大,该区域发育地质灾害共35处。软质岩组、顺向坡结构的斜坡区与河流两侧地质灾害数量也较多。按照地质环境差异和滑坡分布规律进行孕灾地质条件复杂、中等和一般分区,研究成果可为地质环境条件相似的地区在风险防控方面提供参考。

关键词：滑坡地形地貌分布规律发育特征孕灾条件三都县贵州省

不同大口黑鲈群体生长性能、肌肉营养成分、肠道形态结构及菌群组成的比较研究

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动物营养学报 2024年第2期36卷 1158-1172页

作者：黄仁善钟纯怡张帝强俊陶易凡李岩董亚伦路思琪徐跑南京农业大学无锡渔业学院无锡214128 中国水产科学研究院淡水渔业研究中心农业农村部淡水渔业和种质资源利用重点实验室无锡214081

本试验旨在比较不同大口黑鲈群体生长性能、肌肉营养成分、肠道形态结构及菌群组成的差异。试验选用4个国内主要大口黑鲈养殖群体:“优鲈3号”[YL3,(18.91±1.54)g]、“优鲈1号”[YL1,(19.54±2.23)g]、台湾群体[CTW,(18.31±1.76)g]与... 详细信息

本试验旨在比较不同大口黑鲈群体生长性能、肌肉营养成分、肠道形态结构及菌群组成的差异。试验选用4个国内主要大口黑鲈养殖群体:“优鲈3号”[YL3,(18.91±1.54)g]、“优鲈1号”[YL1,(19.54±2.23)g]、台湾群体[CTW,(18.31±1.76)g]与杂交群体(HYB,地方选育种♀×北方亚种♂,(18.80±1.72)g]各180尾,每群3个重复,每个重复60尾。养殖120 d后,对4个大口黑鲈群体的生长性能、肌肉营养成分、肠道形态结构以及菌群组成进行比较分析。结果表明:HYB和CTW的终末体质量、增重率和特定生长率均显著高于YL1和YL3(P<0.05),且HYB的脏体比、肝体比和饲料系数最低。HYB的肥满度、后肠绒毛宽度以及肌肉中饱和脂肪酸、单不饱和脂肪酸和多不饱和脂肪酸含量显著高于其他3个群体(P<0.05)。基于16S rRNA测序对肠道菌群进行alpha多样性分析、物种差异分析和功能预测发现,大口黑鲈肠道优势菌门是厚壁菌门、变形菌门、梭杆菌门以及放线菌门,肠道鲸杆菌属显著富集于HYB;PICRUSt2功能预测表明新陈代谢、遗传信息处理以及环境信息处理等功能在HYB中的平均丰度更高;通过斯皮尔曼相关性分析发现,肠道菌群功能与后肠的绒毛高度和绒毛宽度呈显著正相关(P<0.05)。综上所述,相较于其他群体,HYB大口黑鲈生长性能提高,肌肉中各类脂肪酸积累增多,肠道形态结构也得到显著改善,肠道菌群的多样性和有益菌丰度提高。

关键词：大口黑鲈不同养殖群体生长性能肌肉营养成分肠道形态结构肠道菌群

Progress of vegetation modelling and future research prospects

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Science China Earth Sciences 2024年第9期67卷 2718-2738页

作者： siqi LI Xu ZHANG Zhengyao lu Jian NI Jianhua lu State Key Laboratory of Tibetan Plateau Earth System Resources and Environment(TPESRE)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China British Antarctic Survey Cambridge CB30ETUnited Kingdom Department of Physical Geography and Ecosystem Science Lund UniversityLund 22362Sweden College of Life Sciences Zhejiang Normal UniversityJinhua 321004China School of Atmospheric Sciences Sun Yat-sen University and Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China

Terrestrial vegetation is a crucial component of the Earth system,and its changes not only represent one of the most distinct aspects of climate change but also exert significant feedback within the climate system by exchanging energy,moisture,and carbon *** quantitatively and mechanistically study climate-vegetation feedback,numerical vegetation models have been developed on the theory of ecophysiological constraints on plant functional *** models eventually can simulate vegetation distribution and succession across different spatial and temporal scales,and associated terrestrial carbon cycle processes by categorizing vegetation into biomes according different plant functional types and their associated environmental *** we review the developing history of vegetation models and provide recent advances and future *** 21st century,static vegetation models,as developed statistical models,can only simulate equilibrated characteristics of vegetation *** last several decades,Dynamic Global Vegetation Models(DGVMs)have been developed to simulate instantaneous responses of vegetation to climate change and associated dynamics,and can be coupled with Earth system models to investigate interactions among atmosphere,ocean,and *** are also widely applied to investigate the dynamics accounting for changes in the geographic distribution patterns of land surface vegetation at different spatial and temporal scales and to assess the impacts of terrestrial carbon and water fluxes and land use *** suggest that future vegetation modeling could integrate with machine learning,and explore vegetation transient response and feedback as well as impacts of process hierarchies and human activities on climate and ecosystem.

关键词： Vegetation models DGVMs Ecosystems Plant functional types Plant functional traits

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富含氧空位的由多金属氧簇辅助的银基异质结用于高效电催化固氮

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Chinese Journal of Catalysis 2024年第7期62卷 209-218页

作者：陈昕煜赵聪聪任静李波刘倩倩李葳杨帆陆思琦赵宇飞颜力楷臧宏瑛东北师范大学化学学院功能材料化学研究所纳米生物传感分析吉林省高等学校重点实验室多酸与网格材料化学教育部重点实验室吉林长春130024 北京化工大学化工资源有效利用国家重点实验室北京100029 衢州资源化工创新研究院浙江衢州323000

目前工业产氨主要依赖传统的Haber-Bosch工艺,然而该工艺条件苛刻,需要高温(350-550℃)和高压(150-250bar),每年消耗全球能源供应的2%,同时排放4.5亿吨二氧化碳(占全球总排放量的1.6%).近年来,科研工作者致力于开发高效率、高选择性的... 详细信息

目前工业产氨主要依赖传统的Haber-Bosch工艺,然而该工艺条件苛刻,需要高温(350-550℃)和高压(150-250bar),每年消耗全球能源供应的2%,同时排放4.5亿吨二氧化碳(占全球总排放量的1.6%).近年来,科研工作者致力于开发高效率、高选择性的固氮电催化剂,但是由于析氢反应的强烈竞争,目前已报道的氮还原催化剂仍然受到低法拉第效率和低氨产率的限制.因此,开发活性位点丰富、氮气吸附能力强、催化性能优异的氮还原电催化剂成为当务之急.贵金属催化剂由于其纳米结构中富含活性位点,并且金属表界面处具有较好的导电性,因此表现出较高的法拉第效率.而分子催化剂因可调的电子结构和明确的构效关系引起了广泛关注.多金属氧簇是一种典型的金属聚阴离子团簇,由氧原子连接的含氧多面体组成,且具备优异的氧化还原性能.因此,本课题组尝试将多金属氧簇分子引入到氮还原催化剂中,并探究其催化机理.本文选取了一个多金属氧簇为前驱体,在溶剂、还原剂和诱导剂共存时,通过一锅法合成了富含氧空位的AgPW_(11)/Ag纳米方块电催化剂.实验结果表明,富含氧空位的AgPW_(11)/Ag异质结催化剂在-0.2 V(***)电位时表现出高达46.02±1.03μg h^(-1)mg^(-1)_(cat).的氨产率和34.07±0.16%的法拉第效率,催化反应能够稳定运行32h且性能未见衰减,显著优于银催化剂.随后系统地研究了AgPW_(11)/Ag催化剂的氮还原活性位点,发现异质结中的银单质为催化反应提供了高导电性的支持,而催化剂中的银氧簇具有较好的电子得失能力,有利于促进氮还原反应中的六电子转移过程.丰富的氧空位利于吸附氮气,也能协同提升AgPW_(11)/Ag对电化学氮还原的催化活性.密度泛函理论计算结果表明,在还原后的银氧簇中,银原子d轨道与氮气π*轨道之间的强相互作用激活了吸附的氮气,促进了第一个质子化过程:*N_(2)向*N-NH的转化(电化学决速步).综上,本工作建立了异质结催化剂的催化性能与其分子结构之间的构效关系,为开发多金属氧簇及其衍生物作为电催化剂提供了依据和思路.

关键词：多酸金属氧簇电催化氮还原氧空位密度泛函理论异质结

Selective control of secondary alcohols upgrading using Ir-catalyzed cross-coupling strategy

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Science China Chemistry 2024年第3期67卷 914-921页

作者： siqi Yang Zeye lu Jiale Ji Qingshu Zheng Tao Tu Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of ChemistryFudan UniversityShanghai 200438China Frontiers Science Center for Transformative Molecules School of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

The selective coupling of alcohols is a fascinating yet challenging approach for upgrading alcohols. Herein, we accomplished the controlled production of β-disubstituted ketones or upgraded secondary alcohols via the Ir-catalyzed cross-coupling of secondary alcohols in excellent yields with broad substrate scopes. This selective control was achieved by using an in-situ generated monoNHC-Ir or a tris-NHC-Ir complex as the catalysts, respectively. Mechanistic studies revealed that the delicate balance between dehydrogenation and hydrogenation abilities of these bifunctional catalysts is crucial for achieving different selectivity. The tris-NHC-Ir complex effectively facilitated dehydrogenation of alcohols and hydrogenation of intermediates, leading to the desired upgraded secondary alcohols. Conversely, the high dehydrogenation ability of the mono-NHC-Ir complex promoted the conversion of formed secondary alcohols back to ketones.

关键词： cross-coupling hydrogen-borrowing NHC-Ir complexes selectivity control upgrading of alcohols

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儿童支气管哮喘的药物治疗研究进展

医学综述 2024年第11期30卷 1394-1398页

作者：鲁思琪王雅妮陈海李玉勤卢红艳常明江苏大学附属医院儿科江苏镇江212000

支气管哮喘是儿科常见呼吸系统疾病,严重危害儿童身心健康、生活质量,甚至危及生命。目前,临床上对于儿童支气管哮喘常选用药物治疗,以达到缓解病痛、抑制病情持续恶化的目的。其常用药物主要分为两类,一类是控制性药物,一类是缓解性药... 详细信息

支气管哮喘是儿科常见呼吸系统疾病,严重危害儿童身心健康、生活质量,甚至危及生命。目前,临床上对于儿童支气管哮喘常选用药物治疗,以达到缓解病痛、抑制病情持续恶化的目的。其常用药物主要分为两类,一类是控制性药物,一类是缓解性药物,分别通过不同的方式产生相应功效,从而平稳地控制病情发展,提高患儿的生活质量。随着临床对儿童支气管哮喘的深入研究,未来其药物的利用将越来越合理化,并研发出各种新药。

关键词：支气管哮喘儿童药物治疗情况