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Construction and Functionalization of Highly Strained N-Doped Zigzag Hydrocarbon Belts

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CCS Chemistry 2023年第1期5卷 117-123页

作者： Ming Xie shuo tong Mei-Xiang Wang MOE Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology Department of ChemistryTsinghua UniversityBeijing 100084

Recent years have witnessed breakthroughs in the study of zigzag hydrocarbon belts.However,the synthesis of heterocycle-containing zigzag molecular belts remains very rare and challenging despite their interesting structures and potential applications in chemistry and materials science.Here,we report the expeditious construction of a highly strained belt[4]arene[4](1,4-dihydropyridine)structure using the fjords-stitching strategy.The synthesis comprised four-fold abnormal m-bromination of four Npivaloylaniline units and Pd_(2)(dba)_(3)/4-Me_(2)NC_(6)H_(4)Pt Bu_(2)-catalyzed intramolecular C-N bond-forming reactions.Subsequent functionalization through Narylations produced a variety of tetraza-embedded octahydrobelt[8]arenes.Further oxidation of p-methoxyphenyl-substituted belt[4]arene[4](1,4-dihydropyridine)with Ag[Al(O^(t)Bu^(F))^(4)]yielded a singlet diradical dication N-doped zigzag belt.

关键词： zigzag molecular belt cyclacene octahydrobeltarenepyridine meta-bromination of Nacylaniline palladium-catalyzed C-N bond formation diradical dication salt

Achieving high carrier mobility and low lattice thermal conductivity in GeTe-based alloys by cationic/anionic co-doping

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Rare Metals 2024年第6期43卷 2784-2795页

作者： Xiao-Qiang Wang Xiao-Quan Hu Jun-Yan Lin Chu-Bin Li Xiao-tong Yu Qi-Yong Chen Li-Li Xi Qi-shuo Yang Han Li Ji-Ye Zhang Shuan-Kui Li Kai Guo School of Physics and Materials Science Guangzhou University Research Center for Advanced Information Materials (CAIM) Huangpu Research & Graduate School of Guangzhou University School of Materials Science and Engineering Shanghai University Materials Genome Institute Shanghai University School of Mechanical and Mining Engineering University of Queensland Key Laboratory of Si-Based Information Materials & Devices and Integrated Circuits Design Department of Education of Guangdong Province

The Ⅳ-Ⅵ compound GeTe is considered as a promising alternative to the toxic PbTe for high-efficiency mid-temperature thermoelectric applications.However,pristine GeTe suffers from a high concentration of Ge vacancies,resulting in an excessively high hole concentration(> 1 × 1021cm-3),which greatly limits its thermoelectric enhancement.To address this issue,CuBiTe2alloying is introduced to increase the formation energy of Ge vacancies in GeTe,thereby inhibiting the high carrier concentration.The carrier scattering caused by the electronegativity difference between different elements is suppressed due to the similar electronegativity of Cu and Ge atoms.A relatively high hole mobility is obtained,which ultimately leads to a high power factor.Additionally,by introducing Se as an alloying element at the anionic site in GeTe,dense point defects with mass/strainfield fluctuations are induced.This contributes to the strengthening of phonon scattering,thereby reducing the lattice thermal conductivity from 1.44 W·m-1·K-1for pristine GeTe to 0.28 W·m-1·K-1for Ge0.95Cu0.05Bi0.05Te0.9Se0.15compound at 623 K.

关键词： GeTe Carrier mobility CuBiTe 2 alloying Lattice thermal conductivity Thermoelectric properties

Attenuated retinoic acid signaling is among the early responses in mouse uterus approaching embryo attachment

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生殖与发育医学(英文) 2024年第1期08卷 61-65页

作者： Diao Honglu Xiao shuo Zhou tong Martin Taylor E. Watford Wendy T. Ye Xiaoqin Department of Infectious Diseases Department of Physiology and Pharmacology College of Veterinary Medicine 3. University of Georgia 4. Athens 5. GA 30602 6. USA Department of Physiology and Cell Biology University of Nevada 9. Reno School of Medicine 10. Reno 11. NV 89557

The uterus is transiently receptive for embryo implantation. It remains to be understood why the uterus does not reject a semi-allogeneic embryo (to the biological mother) or an allogeneic embryo (to a surrogate) for implantation. To gain insights, we examined uterine early response genes approaching embryo attachment on day 3 post coitum (D3) at 22 hours when blue dye reaction, an indication of embryo attachment, had not manifested in mice. C57BL/6 pseudo-pregnant (control) and pregnant mouse uteri were collected on D3 at 22 hours for microarray analysis. The self-assembling-manifold (SAM) algorithm identified 21,858 unique probesets. Principal component analysis indicated a clear separation between the pseudo-pregnant and pregnant groups. There were 106 upregulated and five downregulated protein-coding genes in the pregnant uterus with fold change (fc) >1.5 andq value <5%. Gene ontology (GO) analysis of the 106 upregulated genes revealed 38 significant GO biological process (GOBP) terms (P <0.05), and 32 (84%) of them were associated with immune responses, with a dominant natural killer (NK) cell activation signature. Among the top eight upregulated protein-coding genes,Cyp26a1 inactivates retinoic acid (RA) whileLrat promotes vitamin A storage, both of which are expected to attenuate RA bioavailability;Atp6v0d2 andGjb2 play roles in ion transport and transmembrane transport;Gzmb,Gzmc, andIl2rb are involved in immune responses; andTdo2 is important for kynurenine pathway. Most of these genes or their related pathways have functions in immune regulations. RA signaling has been implicated in immune tolerance and immune homeostasis, and uterine NK cells have been implicated in immunotolerance at the maternal-fetal interface in the placenta. The mechanisms of immune responses approaching embryo attachment remain to be elucidated. The coordinated effects of the early response genes may hold the keys to the question of why the uterus does not reject an implanting embryo.

关键词： Embryo attachment Pseudo-pregnant uterus Pregnant uterus Natural killer cell activation signature Retinoic acid bioavailability Transmembrane transport and ion transport

语义—语用接口上中国英语学习者对等级形容词的习得研究

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外国语 2024年第1期47卷 79-89页

作者：徐彤冯硕北京大学外国语学院北京100871

本文探究中国英语学习者对语义—语用接口上等级形容词的习得情况,以及伤面子语境如何影响形容词在否定句中的推导,旨在丰富对语义—语用接口上二语者语用推导能力的认识。本研究采用两个可接受性判断任务,结果发现二语者在无语境的情况... 详细信息

本文探究中国英语学习者对语义—语用接口上等级形容词的习得情况,以及伤面子语境如何影响形容词在否定句中的推导,旨在丰富对语义—语用接口上二语者语用推导能力的认识。本研究采用两个可接受性判断任务,结果发现二语者在无语境的情况下(实验一)表现出与母语者相同程度的否定语义加强和极性不对称性。然而,在伤面子语境中(实验二),二语者出现了与英语母语者不同的表现,且此表现很大程度上受到了伤面子因素的影响。本研究期望为语义—语用接口上的二语习得研究和二语者语用推导能力研究带来新的借鉴。

关键词：等级形容词否定语义加强极性不对称性语义—语用接口

Reconfigurable and polarization-dependent optical filtering for transflective full-color generation utilizing low-loss phase-change materials

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Journal of Semiconductors 2024年第7期45卷 46-53页

作者： shuo Deng Mengxi Cui Jingru Jiang Chuang Wang Zengguang Cheng Huajun Sun Ming Xu Hao tong Qiang He Xiangshui Miao School of Integrated Circuits Huazhong University of Science and TechnologyWuhan 430074China Hubei Yangtze Memory Laboratories Wuhan 430205China School of Microelectronics Fudan UniversityShanghai 200433China

All-dielectric metasurface, which features low optical absorptance and high resolution, is becoming a promising candidate for full-color generation. However, the optical response of current metamaterials is fixed and lacks active tuning. In this work, we demonstrate a reconfigurable and polarization-dependent active color generation technique by incorporating low-loss phase change materials(PCMs) and CaF_2 all-dielectric substrate. Based on the strong Mie resonance effect and low optical absorption structure, a transflective, full-color with high color purity and gamut value is achieved. The spectrum can be dynamically manipulated by changing either the polarization of incident light or the PCM state. High transmittance and reflectance can be simultaneously achieved by using low-loss PCMs and substrate. The novel active metasurfaces can bring new inspiration in the areas of optical encryption, anti-counterfeiting, and display technologies.

关键词： structural color reconfigurable all-dielectric metasurfaces phase change material

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深度学习在动物行为分析中的应用研究进展

计算机科学与探索 2024年第3期18卷 612-626页

作者：申通王硕李孟秦伦明上海电力大学电子与信息工程学院上海201306 中国科学院上海微系统与信息技术研究所上海200050

近年来动物行为分析已成为脑科学与人工智能等领域的重要研究手段之一,研究者基于深度学习的图像分析技术,构建了自动化、智能化的动物行为分析方法。相较于传统的动物行为分析方法,该类方法无需对动物进行特殊标记,可高效地对动物的姿... 详细信息

近年来动物行为分析已成为脑科学与人工智能等领域的重要研究手段之一,研究者基于深度学习的图像分析技术,构建了自动化、智能化的动物行为分析方法。相较于传统的动物行为分析方法,该类方法无需对动物进行特殊标记,可高效地对动物的姿态进行估计和跟踪,实验情景贴近自然情况,为复杂的动物行为实验提供了潜在可能性。对深度学习在动物行为分析中的应用研究进行综述,首先简要分析动物行为分析的任务及现状;然后重点介绍并比较现有的基于深度学习的动物行为分析工具,根据实验分析的行为维度,将该类工具分为二维的动物行为分析工具和三维的动物行为分析工具,并对工具的功能、性能以及适用范围进行论述;进而介绍了现有的动物数据集和评价指标,对现有的动物行为分析工具所利用的算法机制从优势、局限性、适用场景做出总结;最后,从数据集、实验范式和低延时性等方面对基于深度学习的动物行为分析工具做出展望。

关键词：动物行为分析方法深度学习动物姿态估计

从信号到知识——基于人工智能的医学影像裸数据诊断价值初探

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Engineering 2024年第3期34卷 60-69页

作者： Bingxi He Yu Guo Yongbei Zhu Lixia tong Boyu Kong Kun Wang Caixia Sun Hailin Li Feng Huang Liwei Wu Meng Wang Fanyang Meng Le Dou Kai Sun tong tong Zhenyu Liu Ziqi Wei Wei Mu shuo Wang Zhenchao Tang Shuaitong Zhang Jingwei Wei Lizhi Shao Mengjie Fang Juntao Li Shouping Zhu Lili Zhou shuo Wang Di Dong Huimao Zhang Jie Tian Beijing Advanced Innovation Center for Big Data-Based Precision Medicine School of Engineering MedicineBeihang UniversityBeijing 100191China Key Laboratory of Big Data-Based Precision Medicine Beihang UniversityMinistry of Industry and Information TechnologyBeijing 100191China CAS Key Laboratory of Molecular Imaging Institute of AutomationChinese Academy of SciencesBeijing 100190China Department of Radiology The First Hospital of Jilin UniversityChangchun 130021China Neusoft Medical Systems Co.Ltd. Shenyang 110167China Neusoft Research of Intelligent Healthcare Technology Co.Ltd. Shenyang 110167China School of Life Science and Technology Xidian UniversityXi’an 710126China Engineering Research Center of Molecular and Neuro Imaging Ministry of EducationXi’an 710126China School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China

Encouraging and astonishing developments have recently been achieved in image-based diagnostic technology.Modern medical care and imaging technology are becoming increasingly inseparable.However,the current diagnosis pattern of signal to image to knowledge inevitably leads to information distortion and noise introduction in the procedure of image reconstruction(from signal to image).Artificial intelligence(AI)technologies that can mine knowledge from vast amounts of data offer opportunities to disrupt established workflows.In this prospective study,for the first time,we develop an AI-based signal-toknowledge diagnostic scheme for lung nodule classification directly from the computed tomography(CT)raw data(the signal).We find that the raw data achieves almost comparable performance with CT,indicating that it is possible to diagnose diseases without reconstructing images.Moreover,the incorporation of raw data through three common convolutional network structures greatly improves the performance of the CT models in all cohorts(with a gain ranging from 0.01 to 0.12),demonstrating that raw data contains diagnostic information that CT does not possess.Our results break new ground and demonstrate the potential for direct signal-to-knowledge domain analysis.

关键词： Computed tomography Diagnosis Deep learning Lung cancer Raw data

水凝胶在周围神经损伤修复领域的应用研究进展

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中国骨伤 2024年第6期37卷 629-634页

作者：秦春孔令同许硕贵海军军医大学研究生院上海200433 海军军医大学附属长海医院创伤骨科上海200433

作为临床常见创伤性疾病之一,周围神经损伤(peripheral nerve injury,PIN)由于损伤后再生速度缓慢,常会引起神经疼痛、异常反射、自主神经紊乱等,甚至出现感觉运动障碍严重影响机体功能。即便作为治疗金标准,自体神经移植也存在供区有... 详细信息

作为临床常见创伤性疾病之一,周围神经损伤(peripheral nerve injury,PIN)由于损伤后再生速度缓慢,常会引起神经疼痛、异常反射、自主神经紊乱等,甚至出现感觉运动障碍严重影响机体功能。即便作为治疗金标准,自体神经移植也存在供区有限、供体损伤等局限性,极大地限制了其临床应用效果。因此,制备适合临床实践的人工神经移植物成为PIN治疗的未来发展趋势,修复损伤缺损和促进神经再生也成为组织工程和再生医学的研究热点。近年来,对人工神经导管(nerve guidance conduits,NGCs)在神经再生修复领域进行了广泛研究,其中支架材料和内填充物作为神经导管的核心要素也成为研究的重点,新材料应用、包埋干细胞/前体细胞、开发负载营养因子及载药缓释系统均取得了一系列成果。本研究探讨了水凝胶及其相关衍生材料在PIN修复领域中的应用进展,为推动组织工程和临床医学的相关研究提供新的思路。

关键词：水凝胶周围神经损伤人工神经导管

Two antibodies show broad,synergistic neutralization against SARS-CoV-2 variants by inducing conformational change within the RBD

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Protein & Cell 2024年第2期15卷 121-134页

作者： Hui Sun Tingting Deng Yali Zhang Yanling Lin Yanan Jiang Yichao Jiang Yang Huang shuo Song Lingyan Cui Tingting Li Hualong Xiong Miaolin Lan Liqin Liu Yu Li Qianjiao Fang Kunyu Yu Wenling Jiang Lizhi Zhou Yuqiong Que Tianying Zhang Quan Yuan tong Cheng Zheng Zhang Hai Yu Jun Zhang Wenxin Luo Shaowei Li Qingbing Zheng Ying Gu Ningshao Xia State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics School of Public HealthSchool of Life SciencesXiamen UniversityXiamen 361102China National Institute of Diagnostics and Vaccine Development in Infectious Diseases School of Public HealthSchool of Life SciencesXiamen UniversityXiamen 361102China State Key Laboratory of Vaccines for Infectious Diseases School of Public HealthSchool of Life SciencesXiamen UniversityXiamen 361102China Xiang An Biomedicine Laboratory Xiamen 361102China Institute for Hepatology National Clinical Research Center for Infectious DiseaseShenzhen Third People's HospitalSchool of MedicineSouthem University of Science and TechnologyShenzhen 518112China The Second Affliated Hospital School of MedicineSouthern University of Science and TechnologyShenzhen 518112China Research Unit of Frontier Technology of Structural Vaccinology Chinese Academy of Medical SciencesXiamen 361102China

Continual evolution of the severe acute respiratory syndrome coronavirus(SARS-CoV-2)virus has allowed for its gradual evasion of neutralizing antibodies(nAbs)produced in response to natural infection or vaccination.The rapid nature of these changes has incited a need for the development of superior broad nAbs(bnAbs)and/or the rational design of an antibody cocktail that can protect against the mutated virus strain.Here,we report two angiotensin-converting enzyme 2 competing nAbs—8H12 and 3E2—with synergistic neutralization but evaded by some Omicron subvariants.Cryo-electron microscopy reveals the two nAbs synergistic neutralizing virus through a rigorous pairing permitted by rearrangement of the 472-489 loop in the receptor-binding domain to avoid steric clashing.Bispecific antibodies based on these two nAbs tremendously extend the neutralizing breadth and restore neutralization against recent variants including currently dominant XBB.1.5.Together,these findings expand our understanding of the potential strategies for the neutralization of SARS-CoV-2 variants toward the design of broad-acting antibody therapeutics and vaccines.

关键词： SARS-CoV-2 broad neutralizing antibody rearrangement synergistic neutralization