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CCS Chemistry 2024年第4期6卷 898-904页

作者： Changpeng Chen wenqing guo Deyong Qiao Junqian Zhou You Wang Shaolin Zhu State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic MaterialsChemistry and Biomedicine Innovation Center(ChemBIC)School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093 School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007 Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Shanghai Jiao Tong UniversityShanghai 200240

Asymmetric migratory hydrofunctionalization of isomeric mixtures of alkenes provides a complementary approach for the selective introduction of a functional group into a remote C(sp3)-H ***,the simultaneous control of both regio-and enantioselectivity in this migratory process is a ***α-alkyl-substituted azacycles are key motifs in pharmaceuticals,natural products,and ***,we report a NiH-catalyzed asymmetric migratory hydroalkylation process for their efficient and selective *** this process,easily available isomeric mixtures of N-heterocyclic alkenes can be directly employed as starting materials,convergently delivering a variety of enantioenrichedα-alkylated azacycles with high levels of regio-and *** synthetic utility of this transformation is demonstrated by the facile synthesis of two bioactive alkaloids,(+)-connine and(R)-*** obtained chiralα-alkylated azacycles also readily undergo diverse derivatization,such as deconstructive halogenation and ring contraction.

关键词： alkenes alkylation asymmetric catalysis isomerization nickel

基于结构功能交叉神经网络的多模态医学图像融合

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光学精密工程 2024年第2期32卷 252-267页

作者：邸敬郭文庆任莉杨燕廉敬兰州交通大学电子与信息工程学院甘肃兰州730070

针对多模态医学图像融合中存在纹理细节模糊和对比度低的问题,提出了一种结构功能交叉神经网络的多模态医学图像融合方法。首先,根据医学图像的结构信息和功能信息设计了结构功能交叉神经网络模型,不仅有效地提取解剖学和功能学医学图... 详细信息

针对多模态医学图像融合中存在纹理细节模糊和对比度低的问题,提出了一种结构功能交叉神经网络的多模态医学图像融合方法。首先,根据医学图像的结构信息和功能信息设计了结构功能交叉神经网络模型,不仅有效地提取解剖学和功能学医学图像的结构信息和功能信息,而且能够实现这两种信息之间的交互,从而很好地提取医学图像的纹理细节信息。其次,利用交叉网络通道和空间特征变化构造了一种新的注意力机制,通过不断调整结构信息和功能信息权重来融合图像,提高了融合图像的对比度和轮廓信息。最后,设计了一个从融合图像到源图像的分解过程,由于分解图像的质量直接取决于融合结果,因此分解过程可以使融合图像包含更多的细节信息。通过与近年来提出的7种高水平方法相比,本文方法的AG,EN,SF,MI,QAB/F和CC客观评价指标分别平均提高了22.87%,19.64%,23.02%,12.70%,6.79%,30.35%,说明本文方法能够获得纹理细节更清晰、对比度更好的融合结果,在主观视觉和客观指标上都优于其他对比算法。

关键词：多模态医学图像融合结构功能信息交叉网络注意力机制分解网络

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基于多尺度对比度增强和跨维度交互注意力机制的红外与可见光图像融合

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红外技术 2024年第7期46卷 754-764页

作者：邸敬梁婵任莉郭文庆廉敬兰州交通大学电子与信息工程学院甘肃兰州730070

针对目前红外与可见光图像融合存在特征提取不足、融合图像目标区域不显著、细节信息缺失等问题,提出了一种多尺度对比度增强和跨维度交互注意力机制的红外与可见光图像融合方法。首先,设计了多尺度对比度增强模块,以增强目标区域强度... 详细信息

针对目前红外与可见光图像融合存在特征提取不足、融合图像目标区域不显著、细节信息缺失等问题,提出了一种多尺度对比度增强和跨维度交互注意力机制的红外与可见光图像融合方法。首先,设计了多尺度对比度增强模块,以增强目标区域强度信息利于互补信息的融合;其次,采用密集连接块进行特征提取,减少信息损失最大限度利用信息;接着,设计了一种跨维度交互注意力机制,有助于捕捉关键信息,从而提升网络性能;最后,设计了从融合图像到源图像的分解网络使融合图像包含更多的场景细节和更丰富的纹理细节。在TNO数据集上对提出的融合框架进行了评估实验,实验结果表明本文方法所得融合图像目标区域显著,细节纹理丰富,具有更优的融合性能和更强的泛化能力,主观性能和客观评价优于其他对比方法。

关键词：红外与可见光图像融合多尺度对比度增强跨模态交互注意力机制分解网络

基于三分支对抗学习和补偿注意力的红外和可见光图像融合

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红外技术 2024年第5期46卷 510-521页

作者：邸敬任莉刘冀钊郭文庆廉敬兰州交通大学电子与信息工程学院甘肃兰州730070 兰州大学信息科学与工程学院甘肃兰州730000

针对现有深度学习图像融合方法依赖卷积提取特征,并未考虑源图像全局特征,融合结果容易产生纹理模糊、对比度低等问题,本文提出一种基于三分支对抗学习和补偿注意力的红外和可见光图像融合方法。首先,生成器网络采用密集块和补偿注意力... 详细信息

针对现有深度学习图像融合方法依赖卷积提取特征,并未考虑源图像全局特征,融合结果容易产生纹理模糊、对比度低等问题,本文提出一种基于三分支对抗学习和补偿注意力的红外和可见光图像融合方法。首先,生成器网络采用密集块和补偿注意力机制构建局部-全局三分支提取特征信息。然后,利用通道特征和空间特征变化构建补偿注意力机制提取全局信息,更进一步提取红外目标和可见光细节表征。其次,设计聚焦双对抗鉴别器,以确定融合结果和源图像之间的相似分布。最后,选用公开数据集TNO和RoadScene进行实验并与其他9种具有代表性的图像融合方法进行对比,本文提出的方法不仅获得纹理细节更清晰、对比度更好的融合结果,而且客观度量指标优于其他先进方法。

关键词：红外可见光图像融合局部-全局三分支局部特征提取补偿注意力机制对抗学习聚焦双对抗鉴别器

Resonance mechanism of flapping wing based on fluid structure interaction simulation

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Chinese Journal of Aeronautics 2024年第5期37卷 243-262页

作者： Yueyang guo wenqing YANG Yuanbo DONG Dong XUE National Key Laboratory of Science and Technology on Aerodynamic Design and Research School of AeronauticsNorthwestern Polytechnical UniversityXi'an 710072China Research&Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518063China Yangtze River Delta Research Institute of Northwestern Polytechnical University Taicang 215400China

Certain insect species have been observed to exploit the resonance mechanism of their *** order to achieve resonance and optimize aerodynamic performance,the conventional approach is to set the flapping frequency of flexible wings based on the Traditional Structural Modal(TSM)***,there exists controversy among researchers regarding the relationship between frequency and aerodynamic *** that the structural response of wings can be influenced by the surrounding air vibrations,an analysis known as Acoustic Structure Interaction Modal(ASIM)is introduced to calculate the resonant *** this study,Fluid Structure Interaction(FSI)simulations are employed to investigate the aerodynamic performance of flapping wings at modal frequencies derived from both TSM and ASIM *** performance is evaluated for various mass ratios and frequency ratios,and the findings indicate that the deformation and changes in vortex structure exhibit similarities at mass ratios that yield the highest aerodynamic ***,the flapping frequency associated with the maximum time-averaged vertical force coefficient at each mass ratio closely aligns with the ASIM frequency,as does the frequency corresponding to maximum ***,the ASIM analysis can provide an effective means for predicting the optimal flapping frequency for flexible ***,it enables the prediction that flexible wings with varying mass ratios will exhibit similar deformation and vortex structure *** paper offers a fresh perspective on the ongoing debate concerning the resonance mechanism of Flexible Flapping Wings(FFWs)and proposes an effective methodology for predicting their aerodynamic performance.

关键词： Flexible Flapping Wing(FFW) Acoustic Structure Interaction Modal(ASIM) Fluid Structure Interaction(FSI) Resonance mechanism Aerodynamic performance

QT400-15托盘铸件气孔和缩松的产生原因及防止措施

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铸造工程 2024年第4期48卷 31-33页

作者：徐宇嘉方奇郭文清麻于科张轲潘密代德利武汉重型机床集团有限公司武汉武重铸锻有限公司湖北武汉430205

介绍了托盘球墨铸铁件的结构及技术要求,阐述了原生产工艺及铸件出现气孔与缩松的位置和特征。分析了托盘产生气孔与缩松缺陷的原因,认为铸型水分过高导致了侵入性气孔缺陷的出现,冷铁使用不合理导致热节处产生了缩松缺陷。通过采取烘... 详细信息

介绍了托盘球墨铸铁件的结构及技术要求,阐述了原生产工艺及铸件出现气孔与缩松的位置和特征。分析了托盘产生气孔与缩松缺陷的原因,认为铸型水分过高导致了侵入性气孔缺陷的出现,冷铁使用不合理导致热节处产生了缩松缺陷。通过采取烘烤砂芯和砂型减少水分含量,提高砂型透气性和增加出气,优化冷铁摆放位置和形状以消除热节,增大冒口尺寸以提升液态补缩,提高铁液碳含量来增强自补缩能力等措施,消除了球墨铸铁托盘的气孔和缩松缺陷。验证试验生产的同型号托盘铸件均未产生气孔与缩松缺陷。

关键词：球墨铸铁托盘铸件气孔缩松

Metabolic profiles and morphological characteristics of leaf tips among different sweet potato(Ipomoea batatas Lam.)varieties

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Journal of Integrative Agriculture 2024年第2期23卷 494-510页

作者： wenqing Tan Xinbo guo Zhangying Wang Rong Zhang Chaochen Tang Bingzhi Jiang Ruixue Jia Yuanyuan Deng Shaohai Yang Jingyi Chen Crops Research Institute Guangdong Academy of Agricultural Sciences/Key Laboratory of Crop Genetic Improvement of Guangdong ProvinceGuangzhou 510640China School of Food Science and Engineering South China University of TechnologyGuangzhou 510640China Sericultural&Agri-Food Research Institute Guangdong Academy of Agricultural Sciences/Key Laboratory of Functional FoodsMinistry of Agriculture and Rural Affairs/Guangdong Key Laboratory of Agricultural Products ProcessingGuangzhou 510610China

Sweet potato leaf tips have high nutritional value,and exploring the differences in the metabolic profiles of leaf tips among different sweet potato varieties can provide information to improve their *** this study,a UPLC-Q-Exactive Orbitrap/MS-based untargeted metabolomics method was used to evaluate the metabolites in leaf tips of 32 sweet potato *** varieties with distinct overall metabolic profiles(A01,A02,and A03),two varieties with distinct profiles of phenolic acids(A20 and A18),and three varieties with distinct profiles of flavonoids(A05,A12,and A16)were *** addition,a total of 163 and 29 differentially expressed metabolites correlated with the color and leaf shape of sweet potato leaf tips,respectively,were identified through morphological *** comparison analysis of the phenotypic traits and a metabolite-phenotypic trait correlation analysis indicated that the color differences of sweet potato leaf tips were markedly associated with ***,the level of polyphenols was correlated with the leaf shape of sweet potato leaf tips,with lobed leaf types having higher levels of polyphenols than the entire leaf *** findings on the metabolic profiles and differentially expressed metabolites associated with the morphology of sweet potato leaf tips can provide useful information for breeding sweet potato varieties with higher nutritional value.

关键词： sweet potato leaf tips phenotypic traits metabolic profile differentially expressed metabolites polyphenols

Polaron interfacial entropy as a route to high thermoelectric performance in DAE-doped PEDOT:PSS films

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National Science Review 2024年第3期11卷 259-270页

作者： Jiajia Zhang Caichao Ye Genwang Wei Liang guo Yuhang Cai Zhi Li Xinzhi Wu Fangyi Sun Qikai Li Yupeng Wang Huan Li Yuchen Li Shuaihua Wang Wei Xu Xuefeng guo wenqing Zhang Weishu Liu Department of Materials Science and Engineering Southern University of Science and Technology Academy for Advanced Interdisciplinary Studies and Guangdong Provincial Key Laboratory of Computational Science and Material Design Southern University of Science and Technology Department of Mechanical and Energy Engineering Southern University of Science and Technology Beijing National Laboratory for Molecular Sciences Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences College of Chemistry and Molecular Engineering National Biomedical Imaging Centre Peking University Guangdong Provincial Key Laboratory of Functional Oxide Materials and Devices Southern University of Science and Technology

Enhancing the thermoelectric transport properties of conductive polymer materials has been a long-term challenge, in spite of the success seen with molecular doping strategies. However, the strong coupling between the thermopower and the electrical conductivity limits thermoelectric performance. Here, we use polaron interfacial occupied entropy engineering to break through this intercoupling for a PEDOT:PSS(poly（3,4-ethylenedioxythiophene）-poly（4-styrenesulfonate）) thin film by using photochromic diarylethene（DAE） dopants coupled with UV-light modulation. With a 10-fold enhancement of the thermopower from 13.5 μV K-1to 135.4 μV K-1and almost unchanged electrical conductivity, the DAE-doped PEDOT:PSS thin film achieved an extremely high power factor of 521.28 μW m-1K-2from an original value of 6.78 μW m-1K-2. The thermopower was positively correlated with the UV-light intensity but decreased with increasing temperature, indicating resonant coupling between the planar closed DAE molecule and PEDOT. Both the experiments and theoretical calculations consistently confirmed the formation of an interface state due to this resonant coupling. Interfacial entropy engineering of polarons could play a critical role in enhancing the thermoelectric performance of the organic film.

关键词： thermoelectric PEDOT: PSS interfacial occupied entropy resonant coupling UV-light modulation

政策驱动、国家发展和环境保护:我国新能源汽车推广的科技传播动力研究

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科学学与科学技术管理 2023年第1期44卷 103-119页

作者：张莉郭文青清华大学新闻与传播学院北京100084

随着能源体系的低碳转型,发展新能源汽车在国家战略和社会生活中愈发重要,推广新能源汽车,媒体对社会公众的科技传播不容忽视。基于框架理论,采用内容分析和语义网络分析方法,考察了2004—2021年《人民日报》和《光明日报》共3 782篇有... 详细信息

随着能源体系的低碳转型,发展新能源汽车在国家战略和社会生活中愈发重要,推广新能源汽车,媒体对社会公众的科技传播不容忽视。基于框架理论,采用内容分析和语义网络分析方法,考察了2004—2021年《人民日报》和《光明日报》共3 782篇有关新能源汽车的报道,分析了我国新能源汽车推广过程中科技传播的历史变迁和发展动力。结果发现,我国新能源汽车的科技传播经历了科技环保理念下的新能源汽车(2004—2009年)、产业政策激励下的新能源汽车(2010—2015年)、成就与挫折并存的新能源汽车(2016—2018年)和多元收益强调下的新能源汽车(2019—2021年)4个阶段。而媒体对新能源汽车推广的科技传播主要受到三大动力因素的影响。第一,国家政策的驱动。政府在不同阶段出台的关于新能源汽车的政策对媒体报道量、新闻框架和媒体关于新能源汽车的话语产生了很大影响。第二,国家发展话语的采用。在推广新能源汽车的策略中,媒体报道被嵌入到国家发展话语中,以提高公众对新技术、新产业的认可度。第三,逐步强化的环境形象建构的需求。媒体报道也向国际社会表明,我国在环境保护问题上已经从被动的“污染解决者”转变为主动的“环保行动者”,反映了我国在国际气候治理中发挥主导作用的转变和“负责任的大国”形象。在现有媒体报道的新闻框架基础上,注重培育消费者的绿色理念、增加新能源汽车技术创新的科普以及关注消费者切身相关的社会议题将有助于新能源汽车的科技传播。

关键词：新能源汽车科技传播框架理论语义网络分析政策驱动国家发展环境保护

Deleterious variants in RNF111 impair female fertility and induce premature ovarian insufficiency in humans and mice

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Science China(Life Sciences) 2024年第7期67卷 1325-1337页

作者： Chengcheng Song Yingying Qin Yan Li Bingyi Yang Ting guo wenqing Ma Dian Xu Keyan Xu Fangfang Fu Li Jin Yanhua Wu Shuyan Tang Xiaojun Chen Feng Zhang Obstetrics and Gynecology Hospital State Key Laboratory of Genetic EngineeringInstitute of Medical Genetics and GenomicsFudan UniversityShanghai 200011China Human Phenome Institute Zhangjiang Fudan International Innovation CenterFudan UniversityShanghai 201203China Center for Reproductive Medicine Cheeloo College of MedicineShandong UniversityJinan 250021China State Key Laboratory of Reproductive Medicine and Offspring Health Key Laboratory of Reproductive Endocrinology of Ministry of EducationNational Research Center for Assisted Reproductive Technology and Reproductive GeneticsShandong Key Laboratory of Reproductive MedicineShandong Provincial Clinical Research Center for Reproductive HealthShandong UniversityJinan 250021China Department of Obstetrics and Gynecology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China National Demonstration Center for Experimental Biology Education School of Life SciencesFudan UniversityShanghai 200433China Department of Gynecology the Tenth People’s Hospital of Tongji UniversityShanghai 200072China Soong Ching Ling Institute of Maternity and Child Health International Peace Maternity and Child Health Hospital of China Welfare InstituteShanghai 200030China

Premature ovarian insufficiency(POI)is a heterogeneous female disorder characterized by the loss of ovarian function before the age of *** represents a significant detriment to female ***,the known POI-causative genes currently account for only a fraction of *** elucidate the genetic factors underlying POI,we conducted whole-exome sequencing on a family with three fertile POI patients and identified a deleterious missense variant in *** a subsequent replication study involving 1,030 POI patients,this variant was not only confirmed but also accompanied by the discovery of three additional predicted deleterious RNF111 *** variants collectively account for eight cases,representing 0.78%of the study cohort.A further study involving 500 patients with diminished ovarian reserve also identified two additional RNF111 ***,RNF111 encodes an E3 ubiquitin ligase with a regulatory role in the TGF-β/BMP signaling *** analysis revealed that RNF111/RNF111 is predominantly expressed in the oocytes of mice,monkeys,and *** further investigate the functional implications of RNF111 variants,we generated two mouse models:one with a heterozygous missense mutation(Rnf111+/M)and another with a heterozygous null mutation(Rnf111^(+/-)).Both mouse models exhibited impaired female fertility,characterized by reduced litter sizes and small ovarian ***,RNA-seq and quantitative proteomics analysis unveiled that Rnf111 haploinsufficiency led to dysregulation in female gonad development and negative regulation of the BMP signaling pathway within mouse *** conclusion,our findings strongly suggest that monoallelic deleterious variants in RNF111 can impair female fertility and induce POI in both humans and mice.

关键词： POI RNF111 female fertility ovarian reserve