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Metal-Free Photocatalytic[4+2]Annulation of Acrylamides with 2-Benzyl-2-bromocarbonyls to Assemble Tetralin-1-carboxamides

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Chinese Journal of Chemistry 2024年第2期42卷 157-163页

作者： Weicai Li Lu Tan Yijun Chen Rui Liu Zhongyu Qi shixuan Yuan Zhanwen Huang Siping Wei Xi Du dong Yi Nuclear Medicine and Molecular Imaging Key Laboratory of Sichuan Province School of PharmacySouthwest Medical UniversityLuzhouSichuan 646000China Department of Chemistry School of Basic Medical ScienceSouthwest Medical UniversityLuzhouSichuan 646000China Department of Pharmacy Affiliated HospitalSouthwest Medical UniversityLuzhouSichuan 646000China

Tetralin-1-carboxamides are frequently incorporated in myriad medicinally important ***,their existing synthetic routes not only suffer from some drawbacks such as tedious procedures,harsh reaction conditions,narrow substrate scope,low yields,and environmental problems,but are also based upon the elaboration of uneasily available non-linear tetralin ***,we describe a metal-and additive-free visible light-induced[4+2]annulation of two simple linear starting materials,namely acrylamides and 2-benzyl-2-bromocarbonyls,through a cascade C(sp^(3))-Br/C(sp^(2))-H bond cleavage,double C-C bond formation,and aromatization *** developed protocol provides a convenient,efficient,and green approach to a variety of tetralin-1-carboxamide derivatives with good functional group ***,the resulting products could also undergo the Licl-mediated mono-decarboxylative cyclization process to further furnish the architecturally novel bridged polycyclic imides with excellentcis-diastereoselectivities.

关键词： Annulation Metal-free Photoredox catalysis Tetralin-1-carboxamide Cyclic imides Synthetic methods C-C coupling Radical reactions Reaction mechanisms

Social and paternal female choice for male MHC genes in golden snub-nosed monkeys(Rhinopithecus roxellana)

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Social and paternal female choice for male MHC genes in gold...

基于联邦特征学习的多机型低剂量CT重建算法

第十六届全国野生动物生态与资源保护学术研讨会

作者： Pei Zhang Bingyi Zhang Derek W.Dunn Xiaoyue Song Kang Huang shixuan dong Fei Niu Meijing Ying Yingying Zhang Ruliang Pan Baoguo Li Shaanxi Key Laboratory of Animal Conservation College of Life Sciences Northwest University Shaanxi Province Engineering & Technology Research Center of Shanbei Cashmere Goats Yulin University

Genes of the major histocompatibility complex(MHC) play important roles in vertebrate immunocompetence. MHC genes thus offer females indirect benefits to mate choice through the production of offspring of an optimal MHC genotype. Females may choose males with specific MHC haplotypes, dissimilar MHC genotypes, MHC heterozygous males or MHC-diverse males. We tested these four alternatives of both female social and paternal choice in a wild population of golden snub-nosed monkeys(Rhinopithecus roxellana) by examining overall genetic variability(via microsatellites) and four MHC-genes(DRB1, DRB2, DQA1 and DQB1). Monte Carlo randomization tests showed that MHC dissimilarity was favored for social choice(males to which females were socially affiliated) and intermediate MHC dissimilarity was favored in paternal choice(fathers of offspring). No evidence of inbreeding avoidance was found for either social or paternal mates. We found that MHC heterozygotes, higher microsatellite multi-locus heterozygosity and higher microsatellites diversity were favored for social mates, and higher microsatellite diversity was favored for paternal mates. Independent of male age, we found that the formation of male-female social pairings is significantly predicted by compatibility based on the sharing of MHC haplotypes. However, we found no evidence of independent genetic effects on the duration of male-female social pairings, male social status(choice for social mates), the number of females with which individual leader males paired, the likelihood of potential male-female pairings producing offspring, or whether males fathered offspring or not. Overall, our findings suggest different genetic factors are involved in social and paternal choice in R. roxellana.

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南方医科大学学报 2024年第2期44卷 333-343页

作者：陈世宣曾栋边兆英马建华南方医科大学生物医学工程学院//广州市医用放射成像与检测技术重点实验室广东广州510515

目的提出一种基于联邦特征学习的多机型低剂量CT重建算法(FedCT),以提升深度学习模型对多CT机型的泛化能力并保护数据隐私。方法FedCT框架在每个协作学习的客户端中设置了一个基于数据-解析模型耦合驱动的Radon反变换智能重建模型作为... 详细信息

目的提出一种基于联邦特征学习的多机型低剂量CT重建算法(FedCT),以提升深度学习模型对多CT机型的泛化能力并保护数据隐私。方法FedCT框架在每个协作学习的客户端中设置了一个基于数据-解析模型耦合驱动的Radon反变换智能重建模型作为局部网络模型,并采用投影域特异性学习策略,在局部投影域保留成像几何特异性。同时,引入联邦特征学习,使用条件特征参数标记局部数据并馈入网络模型进行编码以在图像域提升网络模型的泛化性。结果在跨站点的多机型、多协议低剂量CT重建实验中,FedCT的重建结果在所有对比联邦学习方法中获得了最高的PSNR(高于次优的联邦学习方法+2.8048、+2.7301、+2.7263)、最高的SSIM指标(高于次优的联邦学习方法+0.0009、+0.0165、+0.0131)以及最低的RMSE指标(低于次优的对比联邦学习方法-0.6687、-1.5956、-0.9962)。在消融实验中,相较于一般联邦学习策略,采用投影特异学习策略的模型在测试集上的PSNR指标的Q1平均提升1.18,RMSE指标的Q3平均降低1.36。在引入联邦特征学习后,FedCT在测试集上的PSNR指标的Q1进一步提升3.56,RMSE指标的Q3进一步降低1.80。结论FedCT为协作构建CT智能重建网络模型提供了有效解决方案,能够在保护数据隐私的基础上,增强网络模型泛化性,进一步地提升网络模型在全局数据上的重建性能。

关键词：计算机断层成像低剂量联邦学习图像重建

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Designing topological and correlated 2D magnetic states via superatomic lattice constructions of zirconium dichloride

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Nano Research 2023年第12期16卷 13509-13515页

作者： Yang Song Wen-Han dong Kuan-Rong Hao shixuan Du Lizhi Zhang Laboratory of Theoretical and Computational Nanoscience National Center for Nanoscience and TechnologyBeijing 100190China Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of SciencesBeijing 100190China State Key Laboratory of Low Dimensional Quantum Physics and Department of Physics Tsinghua UniversityBeijing 100084China

Magnetic materials could realize the intriguing quantum anomalous Hall effect and metal-to-insulator transition when combined with band topology or electronic correlation,which have broad prospects in quantum information,spintronics,and ***,we propose the approach of designing novel two-dimensional(2D)magnetic states via d-orbital-based superatomic ***,we chose triangular zirconium dichloride disks as superatoms to construct the honeycomb superatomic *** first-principles calculations,we identified a series of 2D magnetic states with varying sizes of *** found the non-uniform stoichiometries and geometric effect of superatomic lattice give rise to spin-polarized charges arranged in different magnetic configurations,containing ferromagnetic coloring triangles,antiferromagnetic honeycomb,and ferromagnetic kagome ***,these magnetic states are endowed with nontrivial band topology or strong correlation,forming an ideal Chern insulator or antiferromagnetic Dirac Mott *** work not only reveals the potential of d-orbital-based superatoms for generating unusual magnetic configurations,but also supplies a new avenue for material engineering at the nanoscale.

关键词： topological state Chern insulator Dirac Mott insulator zirconium dichloride superatomic lattice kagome lattice

Superconductivity and topological aspects of two-dimensional transition-metal monohalides

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npj Computational Materials 2022年第1期8卷 1763-1770页

作者： Wen-Han dong Yu-Yang Zhang Yan-Fang Zhang Jia-Tao Sun Feng Liu shixuan Du Beijing National Center for Condensed Matter Physics and Institute of Physics Chinese Academy of SciencesBeijing100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing100049China CAS Center for Excellence in Topological Quantum Computation Beijing100190China School of Integrated Circuits and Electronics MIIT Key Laboratory for Low-Dimensional Quantum Structure and DevicesBeijing Institute of TechnologyBeijing100081China Department of Materials Science and Engineering University of UtahSalt Lake CityUtah84112USA Songshan Lake Materials Laboratory Dongguan523808China

Two-dimensional(2D)superconducting states have attracted much recent interest,especially when they coexist with nontrivial band topology which affords a promising approach towards Majorana *** first-principles calculations,we predict van der Waals monolayered transition-metal monohalides MX(M=Zr,Mo;X=F,Cl)as a class of 2D superconductors with remarkable transition temperature(5.9–12.4 K).Anisotropic Migdal-Eliashberg theory reveals that ZrCl have a single superconducting gap∆~2.14 meV,while MoCl is a two-gap superconductor with∆~1.96 and 1.37 *** Z_(2)band topology of 2D MX is further demonstrated that MoF and MoCl are candidates for realizing topological ***,the Dirac phonons of ZrCl and MoCl contribute w-shape phononic edge states,which are potential for an edge-enhanced electron-phonon *** findings demonstrate that 2D MX offers an attractive platform for exploring the interplay between superconductivity,nontrivial electronic and phononic topology.

关键词： topological transition nontrivial

Nonvolatile electrical control of spin polarization in the 2D bipolar magnetic semiconductor VSeF

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npj Computational Materials 2023年第1期9卷 1838-1847页

作者： Yuhui Li Jun Deng Yan-Fang Zhang Xin Jin Wen-Han dong Jia-Tao Sun Jinbo Pan shixuan Du Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of Sciences100190 BeijingChina University of Chinese Academy of Sciences Chinese Academy of Sciences100190 BeijingChina School of Integrated Circuits and Electronics MIIT Key Laboratory for Low-Dimensional Quantum Structure and DevicesBeijing Institute of Technology100081 BeijingChina Songshan Lake Materials Laboratory 523808 DongguanChina CAS Center for Excellence in Topological Quantum Computation 100190 BeijingChina

Nonvolatile electrical control of spin polarization in two-dimensional(2D)magnetic semiconductors is greatly appealing toward future low-dissipation spintronic ***,we report a 2D material VSeF,which is an intrinsic bipolar magnetic semiconductor(BMS)featured with opposite spin-polarized valence and conduction band *** then propose a general nonvolatile strategy to manipulate both spin-polarized orientations in BMS materials by introducing a ferroelectric gate with proper band *** spin-up/spin-down polarization of VSeF is successfully controlled by the electric dipole of ferroelectric bilayer Al_(2)Se_(3),verifying the feasibility of the design *** interfacial doping effect from ferroelectric gate also plays a role in enhancing the Curie temperature of the VSeF *** types of spin field effect transistors,namely multiferroic memory and spin filter,are further achieved in VSeF/Al_(2)Se_(3) and VSeF/Al_(2)Se_(3)/Al_(2)Se_(3) multiferroic heterostructures,*** work will stimulate the application of 2D BMS materials in future spintronic nanodevices.

关键词： ferroelectric volatile magnetic

Red blood cell membrane-camouflaged nanoparticles loaded with AIEgen and Poly(I: C) for enhanced tumoral photodynamic-immunotherapy

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National Science Review 2021年第6期8卷 46-59页

作者： Jun Dai Meng Wu Quan Wang Siyang Ding Xiaoqi dong Liru Xue Qingqing Zhu Jian Zhou Fan Xia shixuan Wang Yuning Hong Department of Obstetrics and Gynecology Tongji HospitalTongji Medical CollegeHuazhong University of Science and Technology Engineering Research Center of Nano-Geomaterials of Ministry of Education Faculty of Materials Science and ChemistryChina University of Geosciences Department of Chemistry and Physics La Trobe Institute for Molecular ScienceLa Trobe University College of Material Chemistry and Chemical EngineeringHangzhou Normal University

Red blood cell(RBC)-mimicking nanoparticles(NPs) offer a promising platform for drug delivery because of their prolonged circulation time, reduced immunogenicity and specific targeting ability. Herein, we report the design and preparation of RBC membrane-bound NPs(M@AP), for tumoral photodynamic-immunotherapy. The M@AP is formed by self-assembly of the positively charged aggregation-induced emission luminogen(AIEgen)(named P2-PPh3) and the negatively charged polyinosinic : polycytidylic acid(Poly(I : C)), followed by RBC membrane encapsulation. P2-PPh3 is an AIE-active conjugated polyelectrolyte with additional photosensitizing ability for photodynamic therapy(PDT), while Poly(I : C) serves as an immune-stimulant to stimulate both tumor and immune cells to activate immunity, and thus reduces tumor cell viability. When applied in tumor-bearing mice, the M@AP NPs are enriched in both the tumor region as a result of an enhanced permeability and retention(EPR)effect, and the spleen because of the homing effect of the RBC-mimicking shell. Upon light irradiation,P2-PPh3 promotes strong ROS generation in tumor cells, inducing the release of tumor antigens(TA). The anti-tumor immunity is further enhanced by the presence of Poly(I : C) in M@AP. Thus, this strategy combines the PDT properties of the AIE-active polyelectrolyte and immunotherapy properties of Poly(I : C) to achieve synergistic activation of the immune system for anti-tumor activity, providing a novel strategy for tumor treatment.

关键词： biomimetic drug delivery system aggregation-induced emission Poly(I : C) immunotherapy photodynamic therapy

Manipulation of Dirac Fermions in Nanochain-Structured Graphene

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Chinese Physics Letters 2021年第9期38卷 74-79页

作者：董文翰包德亮孙家涛刘峰杜世萱 Institute of Physics and University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100190China School of Information and Electronics MIIT Key Laboratory for Low-Dimensional Quantum Structure and DevicesBeijing Institute of TechnologyBeijing 100081China Department of Materials Science and Engineering University of UtahSalt Lake CityUtah 84112USA CAS Center for Excellence in Topological Quantum Computation Beijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China

Graphene has afforded an ideal 2D platform for investigating a rich and fascinating behavior of Dirac ***,we develop a theoretical mechanism for manipulating the Dirac fermions in graphene,such as from type- Ⅰ to type-Ⅱ and type-Ⅲ,by a top-down nanopatterning *** demonstrate that by selective chemical adsorption to pattern the 2D graphene into coupled 1D armchair chains(ACs),the intrinsic isotropic upright Dirac cone becomes anisotropic and strongly *** on model analyses and first-principles calculations,we show that both the shape and tilt of Dirac cone can be tuned by the species of chemisorption,e.g.,halogen vs hydrogen,which modifies the strength of inter-AC ***,the topological edge states and transport properties of the engineered Dirac fermions are *** work sheds lights on understanding the Dirac fermions in a nanopatterned graphene platform,and provides guidance for designing nanostructures with novel functionality.

关键词： Dirac Fermi topological

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月球熔岩管探测中月表杂波识别方法仿真

空间科学学报 2023年第5期43卷 853-863页

作者：马士璇董晓龙朱迪马剑英白东锦中国科学院国家空间科学中心北京100190 中国科学院大学北京100049

月球上可能存在大量可用于抗辐射、躲避陨石撞击和月球表面极端温度变化的熔岩管。月球表面杂波识别以及与熔岩管目标回波的区分是月球熔岩管目标探测的重要问题。根据高频电磁波与低频电磁波在月壤中的路径衰减快慢不同,熔岩管道高低... 详细信息

月球上可能存在大量可用于抗辐射、躲避陨石撞击和月球表面极端温度变化的熔岩管。月球表面杂波识别以及与熔岩管目标回波的区分是月球熔岩管目标探测的重要问题。根据高频电磁波与低频电磁波在月壤中的路径衰减快慢不同,熔岩管道高低频功率比与月表杂波高低频功率比不同的特征,提出了一种利用高低频电磁波功率比进行月表杂波识别的方法。基于分辨率、回波功率、信杂比和信噪比对熔岩管探测雷达进行了参数优化设计,建立了仿真系统,利用伪谱时域方法对不同走向的月球熔岩管回波进行了仿真研究。仿真结果表明了利用回波的高低频功率比区分月表杂波和熔岩管回波的有效性,熔岩管道高低频回波和月表杂波高低频回波功率比与熔岩管埋深度呈正相关,与频率比呈正相关。

关键词：月球熔岩管探地雷达杂波伪谱时域方法

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