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Double [5]carbohelicene: facile synthesis, chiroptical properties,isomerization study, and lasing application

Science China Chemistry 2025年第1期68卷 233-240页

作者： peipei Liu Yantong Li Meng-Xiang Wu Hao Kang Xiao-Li Zhao Lin Xu Linlin Liu Xiaodong Li Junfeng fang Zhiwei fang Ya Cheng Hai-Bo Yang Huakang yu Xueliang Shi State Key Laboratory of petroleum Molecular & process Engineering Shanghai Key Laboratory of Green Chemistry and Chemical ProcessesSchool of Chemistry and Molecular Engineering East China Normal University School of physics and Optoelectronics South China University of Technology Institute of polymer Optoelectronic Materials & Devices State Key Laboratory of Luminescent Materials & Devices South China University of Technology School of physics and Electronic Science Engineering Research Center of Nanophotonics & Advanced Instrument Ministry of EducationEast China Normal University State Key Laboratory of precision Spectroscopy School of Physics and Electronic Science East China Normal University

Double carbohelicenes have attracted considerable attention due to their aesthetic structures, distinct π-conjugation extension, inherent chirality, and intriguing optical and electronic properties. Herein, the concise de novo synthesis of a new double[5]carbohelicene 1 together with its chiroptical properties, isomerization process and lasing application is presented. 1 was synthesized by a simple protocol involving the formation of a 6,6′-bipentacene as the key intermediate. It is worth noting that1 existed as two diastereomers 1-pp/MM and 1-pM, which were successfully isolated and unambiguously confirmed by Xray crystallography. The optical resolution of the racemic 1-pp/MM was successfully achieved by chiral-phase highperformance liquid chromatography（HpLC）, and 1-pp and 1-MM were characterized by circular dichroism. Interestingly, it was found that 1-pp/MM could be completely isomerized to 1-pM upon heating, and the detailed thermodynamics and kinetics of the isomerization process were systematically investigated. 1-pM exhibited deep-red luminescence with emission maximum at 723 nm and fluorescence quantum yield as high as 32.95%. Consequently, we can showcase the lasing application of 1-pM by doping with epoxy resin to assemble a bottle microlaser spontaneously, which the lasing wavelength is 796.6 nm at a threshold of 0.8 m J cm-2. We believe that our studies, including the facile synthesis methodology, detailed isomerization studies, and lasing application, will shed some light on the design and synthesis of novel carbohelical systems with more functions.

关键词： double carbohelicene optical resolution organic laser isomerization X-ray diffraction

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Leveraging ROTI map derived from Indonesian GNSS receiver network for advancing study of Equatorial plasma Bubble in Southeast/East Asia

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Earth and planetary physics 2025年第1期9卷 101-116页

作者： prayitno Abadi Ihsan N.Muafiry Teguh N.pratama Angga Y.putra Suraina Gatot H.pramono Sidik T.Wibowo febrylian f.Chabibi Umar A.Ahmad Wildan p.Tresna Asnawi Research Center for Climate and Atmosphere Indonesian National Research and Innovation Agency(BRIN)BandungIndonesia School of Electrical Engineering Telkom UniversityBandungIndonesia Directorate of Laboratory Management facilities and Science and Technology park Indonesian National Research and Innovation Agency(BRIN)PontianakIndonesia Geophysics Laboratory Master Program in PhysicsUniversitas Gadjah Mada(UGM)YogyakartaIndonesia Research Center for Space Indonesian National Research and Innovation Agency(BRIN)BandungIndonesia Indonesian Geospatial Information Agency(BIG) JakartaIndonesia Research Center for photonics Indonesian National Research and Innovation Agency(BRIN)Tangerang SelatanIndonesia Department of Earth and planetary Sciences Hokkaido UniversitySapporoJapan

This paper highlights the crucial role of Indonesia’s GNSS receiver network in advancing Equatorial plasma Bubble(EpB)studies in Southeast and East Asia,as ionospheric irregularities within EpB can disrupt GNSS signals and degrade positioning *** by the Indonesian Geospatial Information Agency(BIG),the Indonesia Continuously Operating Reference Station(Ina-CORS)network comprises over 300 GNSS receivers spanning equatorial to southern low-latitude ***-CORS is uniquely situated to monitor EpB generation,zonal drift,and dissipation across Southeast *** provide a practical tool for EpB research,by sharing two-dimensional rate of Total Electron Content(TEC)change index(ROTI)derived from this *** generate ROTI maps with a 10-minute resolution,and samples from May 2024 are publicly available for further scientific *** preliminary findings from the ROTI maps of Ina-CORS are ***,the Ina-CORS ROTI maps reveal that the irregularities within a broader EpB structure persist longer,increasing the potential for these irregularities to migrate farther ***,we demonstrate that combined ROTI maps from Ina-CORS and GNSS receivers in East Asia and Australia can be used to monitor the development of ionospheric irregularities in Southeast and East *** have demonstrated the combined ROTI maps to capture the development of ionospheric irregularities in the Southeast/East Asian sector during the G5 Geomagnetic Storm on May 11,*** observed simultaneous ionospheric irregularities in Japan and Australia,respectively propagating northwestward and southwestward,before midnight,whereas Southeast Asia’s equatorial and low-latitude regions exhibited irregularities *** sharing ROTI maps from Indonesia and integrating them with regional GNSS networks,researchers can conduct comprehensive EpB studies,enhancing the understanding of EpB behavior across Southeast and East Asia and contributing significantly to ionosphe

关键词： Equatorial plasma Bubble(EpB) GNSS receivers’network Indonesia Continuously Operating Reference Station(Ina-CORS) ionospheric map Rate of TEC change index(ROTI)map

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Single-cell transcriptomic profiling reveals ZEB1-mediated regulation in microglial subtypes and the impact of exercise on neuroinflammatory responses

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Traditional Medicine Research 2025年第2期10卷 55-64页

作者： Jin-fang Wu Yi-Sheng Chen yu-Chun Xie Department of Rehabilitation Medicine Jiangsu Province Geriatric HospitalNanjing 210024China fujian Key Laboratory of Toxicant and Drug Toxicology Medical CollegeNingde Normal UniversityNingde 352100China Central Laboratory Jiangsu Province Geriatric HospitalNanjing 210024China

Background:This study aims to identify distinct cellular subtypes within brain tissue using single-cell transcriptomic analysis,focusing on specific biomarkers that differentiate cell types and the effects of traditional and exercise ***:four samples were analyzed:older control(OC),older exercise(OE),younger control(YC),and younger exercise(YE).Single-cell RNA sequencing was used to distinguish cellular subtypes through their biomarker *** visualization included violin and t-SNE plots to illustrate biomarker expression across cell clusters such as oligodendrocytes,microglia,and ***,BV2 cells were exposed to amyloid-beta fragments to simulate Alzheimer’s disease,assessing the impact of exercise-induced cellular ***:Distinct cellular subtypes were identified:oligodendrocytes(MBp,St18),microglia(Dock8),and astrocytes(Aqp4,Gpc5).Sample OE was predominantly oligodendrocytes,while YE had more astrocytes,inhibitory neurons,and Canal-Retzius *** showed a significant presence of Olfm3+ganglion ***1 gene knockout revealed changes in SMAD family gene expression,which regulate *** stress levels were also ***:This profiling enhances our understanding of brain cellular functions and interactions,potentially informing targeted therapies in neurological *** may influence brain cell immune responses and cell death pathways by regulating specific gene expressions,offering new insights for treating neuroinflammation and degeneration.

关键词： single-cell transcriptomics brain tissue cellular subtypes biomarker expression neuronal diversity

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Experimental demonstration of 220-GHz terahertz signals wireless transmission over 4.6 km

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Science China(Information Sciences) 2025年第1期68卷 386-388页

作者： Yi WEI Jianjun yu Mingxu WANG Xiongwei YANG Qiutong ZHANG Jingwen TAN Bing ZHANG Ying WU Yang HAN peng TIAN Wen ZHOU Kaihui WANG feng ZHAO State Key Laboratory of ASIC and System Key Laboratory for Information Science of Electromagnetic Waves (MoE)School of Information Science and Technology Fudan University School of Electronic Engineering Xi'an University of Posts and Telecommunications

The advancement of terahertz (THz) communication technology drives the evolution of wireless communication systems,offering novel pathways and technical means for the development of future 6G communication *** wireless communication systems are often constrained by bandwidth limitations of electronic devices in high frequency ***,THz communication technology leverages the characteristics of electromagnetic waves to transcend these limitations,enabling communication athigher frequencies and wider bandwidths.

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High-dose dexamethasone regulates microglial polarization via the GR/JAK1/STAT3 signaling pathway after traumatic brain injury

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Neural Regeneration Research 2025年第9期20卷 2611-2623页

作者： Mengshi Yang Miao Bai yuan Zhuang Shenghua Lu Qianqian Ge Hao Li yu Deng Hongbin Wu Xiaojian Xu fei Niu Xinlong Dong Bin Zhang Baiyun Liu Beijing Tiantan Hospital Capital Medical UniversityBeijingChina Department of Neurology The First Hospital of Tsinghua UniversityBeijingChina Department of Neurotrauma and Beijing Key Laboratory of Central Nervous System Injury Beijing Neurosurgical InstituteCapital Medical UniversityBeijingChina Department of Critical Care Medicine Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Center for Nerve Injury and Repair Beijing Institute of Brain DisordersChina National Clinical Research Center for Neurological DiseasesBeijingChina

Although microglial polarization and neuroinflammation are crucial cellular responses after traumatic brain injury,the fundamental regulatory and functional mechanisms remain insufficiently *** potent anti-inflammato ry agents,the use of glucoco rticoids in traumatic brain injury is still controversial,and their regulatory effects on microglial polarization are not yet *** the present study,we sought to determine whether exacerbation of traumatic brain injury caused by high-dose dexamethasone is related to its regulatory effects on microglial polarization and its mechanisms of *** vitro cultured BV2 cells and primary microglia and a controlled cortical impact mouse model were used to investigate the effects of dexamethasone on microglial ***,dexamethasone,RU486(a glucocorticoid receptor antagonist),and ruxolitinib(a Janus kinase 1 antagonist)were ***-sequencing data obtained from a C57BL/6 mouse model of traumatic brain injury were used to identify potential targets of *** Morris water maze,quantitative reverse transcription-polymerase chain reaction,western blotting,immunofluorescence and confocal microscopy analysis,and TUNEL,Nissl,and Golgi staining were performed to investigate our ***-throughput sequencing results showed that arginase 1,a marker of M2 microglia,was significantly downregulated in the dexamethasone group compared with the traumatic brain injury group at3 days post-traumatic brain *** dexamethasone inhibited M1 and M2 microglia,with a more pronounced inhibitory effect on M2microglia in vitro and in *** receptor plays an indispensable role in microglial polarization after dexamethasone treatment following traumatic brain ***,glucocorticoid receptor activation increased the number of apoptotic cells and neuronal death,and also decreased the density of dendritic spines.A possible downstream receptor signaling mechanism is th

关键词： apoptosis BV2 microglia dexamethasone glucocorticoid receptor glucocorticoids innate immune system microglial polarization neuroinflammation primary microglia traumatic brain injury

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Asymmetric interfacial engineering regulated charge distribution on Ru/Ni-N-C sites for efficient hydrogen evolution reaction in alkaline and seawater electrolytes

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Science China Chemistry 2025年

作者： Rui yu Xi Cao Chengyang Zhu Qingqing Chen Ziyi Yan Binbin Jiang Junjie Mao Xianwen Wei Key Laboratory of Electrochemical Clean Energy of Anhui Higher Education Institutes College of Chemistry and Materials ScienceAnhui Normal University Anhui provincial Key Laboratory of Advanced Catalysis and Energy Materials School of Chemistry and Chemical Engineering Anqing Normal University School of Chemistry and Chemical Engineering Anhui University of Technology

Developing highly efficient and cost-effective electrocatalysts for hydrogen evolution reaction（HER） is grandly challenging in alkaline and alkaline seawater electrolytes. Herein, the asymmetric interfacial active sites with Ru nanoparticles and Ni single atoms in Ru/Ni-N-C were designed through a solvothermal-pyrolysis process. Constructing highly asymmetric interfacial active sites with a strong electron delocalization effect significantly improves HER kinetics. As expected, Ru/Ni-N-C requires low overpotentials with around 20 mV at 10 mA cm-2and robust durability over 48 h in alkaline and alkaline seawater *** at 200 mA cm-2, the overpotentials are close to 100 mV in both above electrolytes for Ru/Ni-N-C. Density function theory calculation results suggest that the asymmetric interface between Ru nanoparticle and Ni-N-C could accelerate the dissociation of water molecules and modulate the hydrogen species, consequently improving the HER performances. This work opens a unique approach for constructing advanced materials for energy conversion.

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Thermally triggered topological polymerization in diacetylene-functionalized covalent organic framework toward enhanced memristive properties

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Science China Chemistry 2025年

作者： panke Zhou yuxing Huang Ziyue yu Cong Zhang Qian Chen Yiping Li Chao Lin Xiong Chen State Key Laboratory of photocatalysis on Energy and Environment Key Laboratory of Advanced Carbon-Based Functional MaterialsCollege of Chemistry Fuzhou University

The development of stimuli-responsive switching memory devices and the elucidation of their switching mechanisms in specific environments are crucial for advancing the field of molecular electronics. Herein, we propose two distinct two-dimensional covalent organic frameworks (COfs), namely py-EDA and py-BDA, incorporating acetylene (-C≡C-) or diacetylene(-C≡C-C≡C-) moieties, respectively, targeting fabricate memory devices exhibiting stimuli-responsive switching *** findings demonstrate that the incorporation of acetylene units effectively modulates the electronic band structure and enhances the degree ofπ-conjugation, resulting in devices that exhibit typical bipolar nonvolatile memory performance. Notably,upon thermal treatment, the memory behavior of the ITO/py-BDA/Ag device transitions to a write-once-read-many-times(WORM) mode, displaying decreased SET voltage, increased ON/Off current ratio, and remarkable retention reliability and cycle stability. This switching behavior is attributed to the occurrence of interlayer solid-state topological polymerization at 350℃, leading to the transformation of diacetylene columnar arrays into enyne chains within py-BDA, thereby further promoting interlayer charge transfer and separation.

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Impacts of pI3K/protein kinase B pathway activation in reactive astrocytes: from detrimental effects to protective functions

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Neural Regeneration Research 2025年第4期20卷 1031-1041页

作者： Ramón pérez-Núñez María fernanda González Ana María Avalos Lisette Leyton Cellular Communication Laboratory Programa de Biología Celular y MolecularCenter for Studies on ExerciseMetabolism and Cancer(CEMC)Instituto de Ciencias Biomédicas(ICBM)Facultad de MedicinaUniversidad de ChileSantiagoChile Advanced Center for Chronic Diseases(ACCDiS) Faculty of Chemical and Pharmaceutical Sciences&Faculty of MedicineUniversidad de ChileSantiagoChile Instituto de Ciencias Biomédicas Facultad de Ciencias de la SaludUniversidad Autónoma de ChileSantiagoChile

Astrocytes are the most abundant type of glial cell in the central nervous *** injury and inflammation,astrocytes become reactive and undergo morphological and functional *** on their phenotypic classification as A1 or A2,reactive astrocytes contribute to both neurotoxic and neuroprotective responses,***,this binary classification does not fully capture the diversity of astrocyte responses observed across different diseases and *** analysis has revealed that reactive astrocytes have a complex landscape of gene expression profiles,which emphasizes the heterogeneous nature of their *** actively participate in regulating central nervous system inflammation by interacting with microglia and other cell types,releasing cytokines,and influencing the immune *** phosphoinositide 3-kinase(pI3K)/protein kinase B(AKT)signaling pathway is a central player in astrocyte reactivity and impacts various aspects of astrocyte behavior,as evidenced by in silico,in vitro,and in vivo *** astrocytes,inflammatory cues trigger a cascade of molecular events,where nuclear factor-κB serves as a central mediator of the pro-inflammatory ***,we review the heterogeneity of reactive astrocytes and the molecular mechanisms underlying their *** highlight the involvement of various signaling pathways that regulate astrocyte reactivity,including the pI3K/AKT/mammalian target of rapamycin(mTOR),αvβ3 integrin/pI3K/AKT/connexin 43,and Notch/pI3K/AKT *** targeting the inactivation of the pI3K/AKT cellular signaling pathway to control reactive astrocytes and prevent central nervous system damage,evidence suggests that activating this pathway could also yield beneficial *** dual function of the pI3K/AKT pathway underscores its complexity in astrocyte reactivity and brain function *** review emphasizes the importance of employing astrocyte-exclusive models to underst

关键词： inflammation integrins neuroprotective neurotoxic phosphatidylinositol 3-kinase reactive astrocytes signal transduction Thy-1(CD90)

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Construction Concept and Innovative practices of Virtual power plants in Megacities Under Electricity Market Environment

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Dianwang Jishu/power System Technology 2025年第1期49卷 103-112页

作者： Tang, Jun Gao, Hongchao yu, Tao Kang, Chongqing State Grid Shanghai Municipal Electric power Company Pudong New Area Shanghai 200122 China National Key Laboratory of New power System Operation and Control [Tsinghua University Haidian District Beijing 100084 China

With the accelerated construction of new power systems, the Virtual power plant (Vpp), a key component of the new energy framework, provides critical support for safe supply, energy conservation, and emission reduction for power systems. However, the increasingly diverse technological forms and application scenarios of Vpps present challenges for standardization in large-scale development. A timely summary and generalization of Vpp development principles, construction pathways, and technical practices can promote technical synergy and drive industry growth. This paper takes the Vpp in a megacity as a typical use case. It thoroughly discusses the top-level design of the Vpp by reviewing and analyzing four perspectives of form, policy, market, and standards. Secondly, this paper examines a multi-spatiotemporal regulation technology system for Vpps from three dimensions precise response, regional coordination, and fast regulation, which supports the normalized operation of Shanghai’s Vpp. Then, this paper introduces the large-scale demonstration outcomes of Shanghai’s Vpp, offering a valuable reference for development constructions and innovative practices of Vpps at the megacity scale. finally, by analyzing the construction and operational outlook of Shanghai's Vpp, this paper distills a clear pathway for its future development. © 2025 power System Technology press. All rights reserved.

关键词： Virtual power plants

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Identification of the active sites and mechanism for partial methane oxidation to methanol over copper-exchanged CHA zeolites

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Science China Chemistry 2020年第6期63卷 850-859页

作者： yu Mao p.Hu School of Chemistry and Chemical Engineering The Queen’s University of BelfastBelfastUK

To make methane a suitable energy carrier and transport less costly,it is an urgent and challenging task for us to convert methane to liquid under mild conditions *** this study,we explored partial methane oxidation to methanol by density functional theory(DfT)calculations using a hybrid functional(HSE06)with van der Waals(vdW)*** stabilities of different active sites over SSZ-13 and SApO-34,two CHA type zeolites,are thoroughly investigated by ab initio molecular dynamics(AIMD)simulations and ab initio thermodynamics *** possible active sites,namely[CuOHCu]2+,[Cu(OH)2Cu]2+,[CuOCu]2+and[CuOH]+,are identified ***-to-methanol reaction mechanisms are further studied upon these most stable active sites,among which[CuOCu]2+and[CuOH]+are proved to be *** migration of species among zeolite pores are also discussed,which accounts for the activity on[CuOH]+*** concept may represent a more complete picture of catalytic reactions over zeolites in general.

关键词： DfT heterogeneous catalysis methane-to-methanol CHA zeolites

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