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Synthetic control of chiral pore surfaces in covalent organic frameworks for enantioselective separation of chiral drugs

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Science China Chemistry 2025年

作者： Shiguo Fu Xiaofeng zhang Kaixuan Wang Linfeng Chen Fan Xia Yong Cui yan Liu School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative Molecules and State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong University Faculty of Materials Science and Chemistry China University of Geosciences

Enantioselective separations of racemates using porous materials are highly attractive and significant in both fundamental research and technological applications. However, achieving controlled chiral pore surfaces to create the necessary driving force for enantiomer discrimination poses a fundamental challenge. Herein, we demonstrate that chiral covalent organic frameworks(COFs) possess the essential characteristics for effective enantioseparations through synthetic control over pore surfaces. We synthesized three 3D chiral COFs (CCOFs) featuring abundant chiral recognition sites on the pore walls via the condensation of enantiopure dialdehyde of 2,2′-dihydroxy-1,1′-binaphthyl and tetraamine. All CCOFs with high stability exhibit an 11-fold interpenetrated framework with tubular open channels, decorated with dihydroxyl or diethoxyl groups. The CCOFs with dihydroxyl groups serve as solid adsorbents for the adsorptive separation and solid-phase extraction of various chiral 1-phenylethanol-derived enantiomers, particularly racemic drugs, achieving up to 98%enantiomeric excess. In contrast, the CCOF with diethoxy groups is unable to resolve the racemates. These CCOF materials can be recycled and reused without any apparent loss of performance. Density functional theory (DFT) calculations reveal that the enantiospecific recognition arises from the well-organized chiral inner sphere and multiple chiral host-guest interactions.

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Metastable seed-crystals: epitaxial growth of branched-array organic heterostructure nanowires

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Science China Chemistry 2025年

作者： Jin Feng Zhen-Yu Geng Ting-Yao Song Ying-Xin Ma Chuan-Zeng Wang Wei zhang Hong-Tao Lin Jin Zhou Shu-Ping zhuo Shu-Hai Chen Xue-Dong Wang School of Chemistry and Chemical Engineering Shandong University of Technology Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & DevicesSoochow University College of Chemistry and Chemical Engineering Hunan Normal University

Tunable light–matter interactions are exhibited by organic low-dimensional crystals, making these crystals a promising platform for organic photonics. However, the precise synthesis of organic low-dimensional crystals remains challenging due to the stochastic nature of molecular nucleation processes. Herein, the directed nucleation process is driven by the introduction of metastable seed-crystals as the trunk, which ultimately leads to branched-array organic heterostructures. The successful formation of organic heterostructures with high-density branched arrays is attributed to the highest attachment energy (Eatt（023）=-104.25 kcal mol-1) of the exposed （023） crystal plane during the seed-crystal growth route. Significantly, these as-prepared heterostructures inherently have an ultralow lattice mismatch ratio η of 0.7%between trunk and branch, which contributes to the multi-channel photon transportation. Therefore, this work provides valuable insights into a versatile synthetic strategy for accessing low-dimensional heterostructures for integrated optoelectronics.

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Synthesis of chiral phosphine derivatives through a copper（I）-catalyzed desymmetric SNAr reaction

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Science China Chemistry 2025年

作者： Shuai zhang Pei-Zhi Liu yan-Bo Li Qi zhang Jun-Zhao Xiao Yi-Fan Wang Tian-Yu Wei Jia-Wei Jiang Ye Wang Qian Peng Liang Yin Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences State Key Laboratory of Elemento-Organic Chemistry and Tianjin Key Laboratory of Biosensing and Molecular Recognition College of Chemistry Frontiers Science Center for New Organic Matter Nankai University Haihe Laboratory of Sustainable Chemical Transformations

Axially chiral phosphines are a class of extremely important ligands in asymmetric catalysis. Herein, an unprecedented copper（I）-catalyzed asymmetric SNAr reaction with HP（S）R2is uncovered, which delivers a series of axially chiral phosphine derivatives in high yields with excellent enantioselectivity. Furthermore, the diastereoselective reaction with the kinetic resolution of racemic HP（S）ArR proceeds smoothly, providing the products with moderate diastereoselectivity and excellent enantioselectivity. Control experiments indicate that HP（S）Ph2is much more active than HPPh2and HP（O）Ph2as the pronucleophile in the present reaction. It is found that the SNAr reaction （the first SNAr） proceeds in a desymmetric manner, providing the desired chiral products while a continued SNAr reaction （the second SNAr） slightly occurs in a kinetic resolution manner in the present catalytic system, which enhances the ee of the desired chiral products. DFTcalculations support a concerted reaction pathway rather than a step-wise mechanism. Finally, axially chiral olefin-phosphines produced by the present method work as suitable ligands in Pdcatalyzed asymmetric allylic substitution with C-, N-, and O-nucleophiles and Rh-catalyzed asymmetric addition of arylboronic acid to benzil.

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Persistent alterations in gray matter in COVID-19 patients experiencing sleep disturbances:a 3-month longitudinal study

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Neural Regeneration Research 2025年第10期20卷 3013-3024页

作者： Kaixuan Zhou Gaoxiong Duan Ying Liu Bei Peng Xiaoyan Zhou Lixia Qin Lingyan Liang Yichen Wei Qingping zhang Xiaocheng Li Haixia Qin Yinqi Lai Yian Lu yan zhang Jiazhu Huang Jinli Huang Yinfei Ouyang Bolin Bin Mingming Zhao Jun Liu Jianrong yang Demao Deng Guangxi Key Laboratory of Special Biomedicine School of MedicineGuangxi UniversityNanningGuangxi Zhuang Autonomous RegionChina Department of Radiology the People’s Hospital of Guangxi Zhuang Autonomous RegionGuangxi Academy of Medical SciencesNanningGuangxi Zhuang Autonomous RegionChina Department of Sleep Medicine the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous RegionChina Department of Radiology The Second Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Guangxi Clinical Research Center for Sleep Medicine the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous RegionChina

Sleep disturbances are among the most prevalent neuropsychiatric symptoms in individuals who have recovered from severe acute respiratory syndrome coronavirus 2 *** studies have demonstrated abnormal brain structures in patients with sleep disturbances who have recovered from coronavirus disease 2019(COVID-19).However,neuroimaging studies on sleep disturbances caused by COVID-19 are scarce,and existing studies have primarily focused on the long-term effects of the virus,with minimal acute phase *** a result,little is known about the pathophysiology of sleep disturbances in the acute phase of *** address this issue,we designed a longitudinal study to investigate whether alterations in brain structure occur during the acute phase of infection,and verified the results using 3-month follow-up data.A total of 26 COVID-19 patients with sleep disturbances(aged 51.5±13.57 years,8 women and 18 men),27 COVID-19 patients without sleep disturbances(aged 47.33±15.98 years,9 women and 18 men),and 31 age-and gender-matched healthy controls(aged 49.19±17.51 years,9 women and 22 men)were included in this *** COVID-19 patients with sleep disturbances were included in a longitudinal *** found that COVID-19 patients with sleep disturbances exhibited brain structural changes in almost all brain *** cortical thicknesses of the left pars opercularis and left precuneus were significantly negatively correlated with Pittsburgh Sleep Quality Index ***,we observed changes in the volume of the hippocampus and its subfield regions in COVID-19 patients compared with the healthy *** 3-month follow-up data revealed indices of altered cerebral structure(cortical thickness,cortical grey matter volume,and cortical surface area)in the frontal-parietal cortex compared with the baseline in COVID-19 patients with sleep *** findings indicate that the sleep disturbances patients had altered morphology in the cortical an

关键词： brain structure cortical gray matter volume cortical surface area cortical thickness hippocampus magnetic resonance imaging Pittsburgh Sleep Quality Index severe acute respiratory syndrome coronavirus 2 infections sleep disturbances sub-cortical volume

Simple Ultrasonic-Assisted Clean Graphene Transfer

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Journal of Electronic Science and Technology 2022年第3期20卷 237-245页

作者： zhuo-Cheng zhang Xiao-Qiu-yan zhang Min Hu the Terahertz Research Center School of Electronic Science and EngineeringUniversity of Electronic Science and Technology of ChinaChengdu610054China the Key Laboratory of Terahertz Technology(Ministry of Education) University of Electronic Science and Technology of ChinaChengdu610054China

Clean graphene transfer has received widespread research attention, where most methods are focused on cleaning the upper surface of graphene to improve the transfer technique. However, the residue formation on the bottom surface of graphene is also inevitable;therefore, cleaning the bottom surface is crucial. In this study, we proposed an improved graphene wet transfer method using an ultrasonic processing(UP) step for etching copper(Cu). Using this method, the bottom surface can be cleaned efficiently. The results of atomic force microscopy(AFM)and Raman spectroscopy mapping revealed that the graphene films transferred with UP had smoother and cleaner surfaces, less contamination, and higher quality than those transferred without UP.

关键词： Chemical vapor deposition(CVD) clean graphene transfer ultrasonic processing

Peficitinib suppresses diffuse-type tenosynovial giant cell tumor by targeting TYK2 and JAK/STAT signaling

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Science China Life Sciences 2025年

作者： Shan Lu Chenxi Cao Wenjia zhang Jiayi Li Jingli yang Zisheng Huang Zhijun Wu Baitao Liu Hongjie Huang Haijun Wang Yongjian Wang Dingge Liu Zhihua zhang Kaiping Liu Gang yang Xi Gong Hui Dai Yingjia Li Erdan Dong Xin zhang yan zhang Haihe Laboratory of Cell Ecosystem Institute of Cardiovascular Diseases The First Affiliated Hospital of Dalian Medical University Institute of Cardiovascular Sciences School of Basic Medical Sciences Peking University Health Science Center Department of Cardiology and Institute of Vascular Medicine Peking University Third HospitalState Key Laboratory of Vascular Homeostasis and Remodeling Peking University Department of Sports Medicine Peking University Third Hospital Institute of Sports Medicine of Peking University Beijing Key Laboratory of Sports Injuries Engineering Research Center of Sports Trauma Treatment Technology and Devices Ministry of Education State Key Laboratory of Membrane Biology Institute of Molecular Medicine College of Future Technology Peking University Peking University Health Science Centre Peking University Department of Immunology School of Basic Medical Sciences NHC Key Laboratory of Medical Immunology Peking University Research Center for Cardiopulmonary Rehabilitation University of Health and Rehabilitation Sciences Qingdao Hospital (Qingdao Municipal Hospital) School of Health and Life Sciences University of Health and Rehabilitation Sciences Research Unit of Medical Science Research Management/Basic and Clinical Research of Metabolic Cardiovascular Diseases Chinese Academy of Medical Sciences

Diffuse-type tenosynovial giant cell tumor(dTGCT) is a destructive but rare benign proliferative synovial neoplasm. Although surgery is currently the main treatment modality for dTGCT, the recurrence risk is up to 50%. Therefore, there is a great need for effective drugs against dTGCT with minor side effects. The Janus kinase(JAK)/signal transducer and activator of transcription(STAT) signaling plays a central role in rheumatoid arthritis(RA), a disease with similar characteristics as dTGCT, but its function in dTGCT remains *** fibroblast-like synoviocytes(FLS) and macrophages were isolated from 10 synovial tissue samples from dTGCT patients for the screening and validation of the five clinically approved JAK inhibitors to treat RA against dTGCT. Cell viability, cell death, inflammation and the activity of the JAK family members of cultured dTGCT FLS(both 2-D and 3-D) and macrophages were investigated for the efficacy of the JAK inhibitors. Here, we found that similar to RA, JAK/STAT signaling was markedly activated in the dTGCT synovium. Of the 5 JAK inhibitors, peficitinib was shown to have the most potency in addressing some of the pathological responses of dTGCT FLS and *** potency of peficitinib was much higher than pexidartinib, which is the only FDA-approved drug for dTGCT. Mechanistically, peficitinib inhibited tyrosine kinase 2(TYK2), a JAK family member necessary for the pathological progression of dTGCT FLS and macrophages. In summary, we not only revealed JAK/STAT(especially TYK2) signaling as the major mechanism underlying dTGCT, but also identified peficitinib as a promising drug against dTGCT.

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Maintaining moderate levels of hypochlorous acid promotes neural stem cell proliferation and differentiation in the recovery phase of stroke

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Neural Regeneration Research 2025年第3期20卷 845-857页

作者： Lin-yan Huang Yi-De zhang Jie Chen Hai-Di Fan Wan Wang Bin Wang Ju-Yun Ma Peng-Peng Li Hai-Wei Pu Xin-Yian Guo Jian-Gang Shen Su-Hua Qi School of Medical Technology Xuzhou Key Laboratory of Laboratory DiagnosticsXuzhou Medical UniversityXuzhouJiangsu ProvinceChina School of Pharmacy Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina Department of Laboratory Medicine Branch Hospital of Huai’an First People’s HospitalHuai’anJiangsu ProvinceChina Department of Laboratory Medicine the Affiliated Hospital of Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina School of Chinese Medicine The University of Hong KongHong Kong Special Administrative RegionChina

It has been shown clinically that continuous removal of ischemia/reperfusion-induced reactive oxygen species is not conducive to the recovery of late ***,previous studies have shown that excessive increases in hypochlorous acid after stroke can cause severe damage to brain *** previous studies have found that a small amount of hypochlorous acid still exists in the later stage of stroke,but its specific role and mechanism are currently *** simulate stroke in vivo,a middle cerebral artery occlusion rat model was established,with an oxygen-glucose deprivation/reoxygenation model established in vitro to mimic *** found that in the early stage(within 24 hours)of ischemic stroke,neutrophils produced a large amount of hypochlorous acid,while in the recovery phase(10 days after stroke),microglia were activated and produced a small amount of hypochlorous ***,in acute stroke in rats,hypochlorous acid production was prevented using a hypochlorous acid scavenger,taurine,or myeloperoxidase inhibitor,4-aminobenzoic acid *** results showed that high levels of hypochlorous acid(200μM)induced neuronal apoptosis after oxygen/glucose deprivation/***,in the recovery phase of the middle cerebral artery occlusion model,a moderate level of hypochlorous acid promoted the proliferation and differentiation of neural stem cells into neurons and *** suggests that hypochlorous acid plays different roles at different phases of cerebral ischemia/reperfusion *** levels of hypochlorous acid(5 and 100μM)promoted nuclear translocation ofβ-*** transfection of single-site mutation plasmids,we found that hypochlorous acid induced chlorination of theβ-catenin tyrosine 30 residue,which promoted nuclear ***,our study indicates that maintaining low levels of hypochlorous acid plays a key role in the recovery of neurological function.

关键词： cell differentiation cerebral ischemia/reperfusion injury chlorination hypochlorous acid microglia neural stem cell neurogenesis nuclear translocation stroke β-catenin

Soil microbial community diversity and distribution characteristics under three vegetation types in the Qilian Mountains, China

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Journal of Arid Land 2023年第3期15卷 359-376页

作者： TONG Shan CAO Guangchao zhang zhuo zhang Jinhu yan Xin Key Laboratory of Tibetan Plateau Land Surface Processes and Ecological Conservation(Ministry of Education) Qinghai Normal UniversityXining 810008China Qinghai Province Key Laboratory of Physical Geography and Environmental Process College of Geographical ScienceQinghai Normal UniversityXining 810008China Academy of Plateau Science and Sustainability People's Government of Qinghai Province and Beijing Normal UniversityXining 810008China

Qilian Mountains in Northwest China is a significant ecological security barrier due to its distinctive geographic setting,which has significant biological resource and gene *** order to assess the soil quality and ecosystem health in this area,we identified the structural characteristics and functional groups of soil microbial *** study focused on Amidongsuo,a typical watershed of the Qilian Mountains,and researched the vertical distribution and dominant populations of soil microorganisms in different habitats,and the relationship between soil microorganisms and environmental *** microorganisms from three grassland plots,five shrubland plots,and five forest plots in Amidongsuo were studied using high-throughput *** Venn diagram showed that the types of bacteria were fewer than those of fungi in *** bacteria Acidobacteriota,Proteobacteria,and Methylomirabilota as well as fungi Basidiomycota,Ascomycota,and Mortierellomycota played dominant roles in Amidongsuo,according to the LEfSe(linear discriminant analysis(LDA)effect size)and community structure *** to the ANOSIM(analysis of similarities)result,for both bacteria and fungi,R values of grassland and shrubland were small(R^(2)=0.045 and R^(2)=0.256,respectively),indicating little difference between these two ***(redundancy analysis)showed a closer relationship between soil nutrients and fungi,and a gradually decreasing correlation between soil nutrients and microorganisms with increasing soil *** were mainly affected by pH,nitrogen(N),and potassium(K),while fungi were mainly affected by ***,fungi had more effect on soil quality than ***,adjustment of soil K content might improve the soil environment of Amidongsuo in the Qilian Mountains.

关键词： fungi bacteria diversity soil nutrient Qilian Mountains

激光诱导荧光技术与地下水重金属原位检测应用进展

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岩矿测试 2025年第1期44卷 19-34页

作者：毛康薛家奇陈卓张华中国科学院地球化学研究所环境地球化学国家重点实验室贵州贵阳550081

对地下水重金属污染进行现场检测,是快速识别重金属种类和评价污染程度的重要手段。激光诱导荧光技术(LIF)利用特定荧光探针,在目标重金属存在下,通过激光诱导荧光探针产生/猝灭荧光,从而完成对重金属的识别和检测,具有快速甄别地下水... 详细信息

对地下水重金属污染进行现场检测,是快速识别重金属种类和评价污染程度的重要手段。激光诱导荧光技术(LIF)利用特定荧光探针,在目标重金属存在下,通过激光诱导荧光探针产生/猝灭荧光,从而完成对重金属的识别和检测,具有快速甄别地下水重金属污染特性和无损获取其价态的优势。本文在简述LIF检测重金属原理和LIF原位检测地下水重金属装备基础上,重点从荧光探针合成及其在重金属传感检测方法的构建上总结了基于不同荧光探针的LIF现场检测重金属的研究进展。目前可用于重金属检测的荧光探针包括以小分子探针、有机大分子和聚集诱导发光为主的有机荧光探针和以金纳米簇、量子点和金属有机框架材料为代表的纳米荧光探针。这些探针的合成及其对应的传感检测方法的构建表明LIF技术在地下水重金属检测中具有巨大优势。而针对地下水重金属检测的LIF设备研发方面的成果虽不如荧光传感检测方法丰富,但已研制出部分重金属的传感器和检测装备,表现出良好的应用前景。未来研究将会聚焦在地下水重金属主控因子识别和抗干扰技术研发、荧光探针合成与LIF检测方法构建、重金属传感部件和检测装备集成研制,以及检测技术标准化,为后续场地地下水典型重金属LIF检测技术的研究提供参考。

关键词：地下水重金属激光诱导荧光荧光探针现场检测