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4篇 您的检索式:作者名="Qiuyan Pei"
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1Prenatal ultrasonographic characteristics and prognosis of isolated redundant foramen ovale flap显示文摘Objective:To analyze the prenatal ultrasonographic characteristics and prognosis of the isolated redundant foramen ovale flap(RFOF).Methods:From January 2014 to December 2021,we collected data on fetal echocardiography analyses and perinatal outcomes for fetuses with isolated RFOF in Peking University People's Hospital.Results:We found that 0.31%(87/28308)of participants have RFOF.The four-chamber results of the foramen ovale flap(FOF)showed that it was stiff and extended>50%or reached the lateral wall of the left atrium(LA)in diastole.As seen from the foramen ovale(FO)channel and four-chamber views,the hypermobile and redundant flap were observed shrinking and stretching with the fetal cardiac cycle,which is similar to jellyfish.The lateral displacement of flow from LA to the left ventricle(LV)around the FOF on color doppler demonstrated thin linear blood flow from the right to left and a reversal of flow across FO.A uniphasic,but not biphasic,pattern of FOF displacement was observed on M-mode.Stages I(23/87)and II(51/87)had a higher ratio of ventricular disproportion than Stage 0(11/87)and III(2/87).We observed the RA/LA(right/left atrium)>1.2 in 53 cases(60.9%),RV/LV(right/left ventricle)>1.2 in 53 cases(60.9%),PA/AO(pulmonary/aortic artery)>1.2 in 53 cases(60.9%),and moderate or severe tricuspid regurgitation in 10 cases and moderate pericardial effusion in 2 cases(2.2%).Seventy-four RFOF cases had follow-up data.Neonatal death occurred in 2 cases;72 fetuses survived with normal or minor heart defects.Conclusion:RFOF should be considered if the left side of the heart of a fetus is smaller and related to hypermobile FOF.For isolated RFOF cases,a monthly follow-up is recommended to monitor arrhythmia or fetal hydrop status.Prompt treatment is recommended for those with adequate gestational age and lung maturity.Yuntao Li Qiuyan Pei Zhenjuan Yang Yani Yan Xiaowei Xue 2022Gynecology and Obstetrics Clinical Medicine2022,2,3:1
2Scrolling bilayer WS2/MoS2 heterostructures for high-performance photo-detection显示文摘Recently,transition metal dichalcogenides(TMDCs)nanoscrolls have exhibited unique electronic and optical properties due to their spiral tubular structures,which are formed by rolling up monolayer TMDCs nanosheets.Inspired by the excellent physical and chemical properties of TMDCs van der Waals heterostructures(vdWHs),it is highly desirable to scroll TMDCs vdWHs for potential optoelectronic applications.In this work,WS2/MoS2 vdWHs nanoscrolls were massively prepared by dropping aqueous alkaline droplet on chemical vapor deposition(CVD)-grown bilayer WS2/MoS2 vdWHs,which were formed by growing monolayer WS2 islands on top of monolayer MoS2 nanosheets simultaneously.The optical microscopy(OM),atomic force microscopy(AFM),ultralow frequency(ULF)Raman spectroscopy and transmission electron microscopy(TEM)were utilized to characterize the WS2/MoS2 vdWHs nanoscrolls.As-obtained WS2/MoS2 vdWHs nanoscrolls exhibited new ULF breathing mode as well as shear mode peaks due to the strong interlayer interaction.Notably,the photosensitivities of WS2/MoS2 vdWHs nanoscrolls-based devices were about ten times higher than those of WS2/MoS2 vdWHs-based devices under blue,green and red lasers,respectively,which could be attributed to the ultrafast charge transfer at alternative WS2/MoS2 and MoS2/WS2 multi-interfaces in scrolled structure.Our work suggested that TMDCs vdWHs scrolls could be promising candidates for optoelectronic applications.Lin Wang Qiuyan Yue Chengjie Pei Huacheng Fan Jie Dai Xiao Huang Hai Li Wei Huang 2020Nano Research2020,13,4:1
3Asymmetric synthesis of ABC tricyclic systems in Daphniphyllum alkaloid显示文摘Efficient synthetic routs for the direct and rapid construction of[5-6-6]ABC tricyclic systems of daphmanidin A-type and calyciphylline A-type alkaloids have been successfully developed.For the daphmanidin A-type,the synthesis of[5-6-6]tricyclic framework utilize a HCl-mediated intramolecular Aldol reaction to construct the bicyclo[2.2.2]octane core and a thermal condensation to afford the ABC ring system.In addition,for the calyciphylline A-type,an improved synthesis of ABC[5-6-6]tricyclic system was developed,featuring an introduction of methyl ester group at C2 before the Pd-catalyzed intramolecular oxidative alkylation to construct the desired bowl-shape tricyclic core with stereochemical control.Huijing Wang Qiuyan Dong Qinxia Xie Pei Tang 2020Chinese Chemical Letters2020,31,3:0
4Characterizing Human Collective Behaviors During COVID-19 — Hong Kong SAR, China, 2020显示文摘Summary What is already known about this topic?People are likely to engage in collective behaviors online during extreme events,such as the coronavirus disease 2019(COVID-19)crisis,to express awareness,take action,and work through concerns.Zhanwei Du Xiao Zhang Lin Wang Sidan Yao Yuan Bai Qi Tan Xiaoke Xu Sen Pei Jingyi Xiao Tim K.Tsang Qiuyan Liao Eric H.YLau Peng Wu Chao Gao Benjamin J.Cowling 2023China CDC weekly2023,5,4:0
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