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中国病理生理杂志 2012年第11期 2049-2049页

作者： HUANG Ya-qian,ZHENG jin-gang,liu Bo,XIE jin-sheng,WANG Wen-gong,GUO Wei,JIA Xin,ZHANG Tao,liu Zi-yi,ZHANG Heng,TANG Chao-shu,ZHU Yi,XU Qing-bo,WANG Xian,KONG Wei(Department of Physiology and Pathophysiology,School of Basic Medical Sciences,Peking University,Key Laboratory of Molecular Cardiovascular Science,Ministry of Education,Beijing 100191,China)

Abdominal aortic aneurysm(AAA)is a life-threatening cardiovascular *** endogenous molecules that modulate the aneurism process remain *** oligomeric matrix protein(COMP)is a matricellular glycoprotein highly expressed... 详细信息

关键词： type 1 receptor,inhibits aortic aneurysm formation

Applications of in-situ solid-state nuclear magnetic resonance in methanol to olefins reaction

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Science China Chemistry 2025年第1期68卷 134-151页

作者： jing Niu Shutao Xu Yingxu Wei Zhongmin liu National Engineering Research Center of Lower-Carbon Catalysis Technology Dalian Institute of Chemical PhysicsChinese Academy of Sciences State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

The methanol-to-olefins（MTO） reaction offers an alternative pathway for the production of low-carbon olefins from non-oil feedstocks. Fundamental research has been impeded by a lack of comprehensive understanding of its underlying mechanism,despite the significant progress made in industry. In-situ solid-state nuclear magnetic resonance（ss NMR） spectroscopy has emerged as a pivotal tool, offering crucial insights into key species under real-time operando conditions. Furthermore, the host–guest interaction between zeolites or surface species residing on zeolites and the reactant/active intermediates is revealed by the combination of in-situ13C MAS NMR and 2D correlation spectroscopy. Moreover, recent technological advancements in hyperpolarization（HP） methods, including HP129Xe NMR and dynamic nuclear polarization（DNP）, have significantly improved the sensitivity of ss NMR, enabling detailed structural and kinetic analysis as well as the detection of trace species. In this feature article, we summarized recent advancements in（in-situ） ss NMR spectroscopy applied to MTO reaction processes,encompassing mechanistic investigations at various stages and the intricate host–guest interactions. These theoretical insights into the dynamic evolution of MTO reactions lay a solid foundation for the optimization of catalytic processes and the development of efficient catalysts, thereby advancing the techniques towards more sustainable and economical production route for olefins.

关键词： MTO zeolites in-situ ssNMR reactive intermediates reaction mechanism

Fast Position and Velocity Determination for Pulsar Navigation Using NML and LSM

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Chinese Journal of Electronics 2017年第6期26卷 1325-1329页

作者： liu jin WU jin XIONG Ling FANG Jiancheng liu gang College of Information Science and Engineering Wuhan University of Science and Technology School of Instrumentation Science and Opto-electronics Engineering Beihang University

To reduce the computational cost, a Fast position and velocity joint determination(FPVD) method based on the Near-maximum likelihood(NML) and the Least square method(LSM) is proposed for X-ray pulsar navigation. Considering the fact that the Doppler effects caused by the velocity of the spacecraft alters the X-ray pulse Time-of-arrival(TOA), we adopt the NML to obtain multi-TOAs, and then utilize the LSM to estimate the variation of TOAs instead of the pulsar profile distortion adopted by the Maximum-likelihood(ML) estimation method. Finally, according to the variation value and TOAs, the position and velocity information of the spacecraft are calculated. The simulation results have demonstrated that the FPVD method is far faster than the ML estimation method, and its accuracy approaches the CramerRao lower bound(CRLB).

关键词： Velocity determination Pulsar Maximum likelihood Least square method

Observation of topological charge transformations in acoustic vortex using passive periodic systems

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 140-147页

作者： Di-Chao Chen Xie liu Changqing Xu Da-Jian Wu Ying Cheng Xiao-Jun liu School of Physics and Technology Nanjing Normal University Key Laboratory of Modern Acoustics School of Physics Nanjing University

Vortex transmutation utilizes a periodic system, which not only enables the alteration of the topological charge(TC) of unstable input vortices but also facilitates their transformation into stable structures. This approach is crucial for investigating the characteristics of vortices in various wave systems. Here, we achieve acoustic vortex TC transmutation by employing a welldesigned dual-structured plate external system(DPES). The interactions between the acoustic vortex and the finite-order discrete rotational symmetry lead to the transformation of its topological charge when complete rotational symmetry is broken to Nthorder discrete symmetry. Our results experimentally demonstrate the acoustic vortex TC transmutation based on passive artificial structures, enabling numerous applications in particle manipulation and information multiplexing as well as advancing our understanding and control over free-space acoustic vortices.

关键词： acoustic vortex topological charge transformation artificial structure

Approach from the laboratory to the field: New strategies in the control of mosquito-borne infectious diseases

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Science China Life Sciences 2025年第1期68卷 303-305页

作者： Ziqian Xu Lianpan Dai Jun liu National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases (NITFID) National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and Prevention CAS Key Laboratory of Pathogen Microbiology and Immunology Institute of MicrobiologyChinese Academy of Sciences

Vector-borne viruses, transmitted among humans and animal hosts through bites of vectors such as mosquitoes and ticks,pose a great and ongoing threat to public health and biosafety(Yang et al., 2022).Among them, dengue virus-induced epidemics, have dramatically increased worldwide in recent decades. The report released by the World Health Organization(WHO) at the end of 2023 showed that dengue epidemic globally surged in2023, with the number of reported cases nearing a historical peak.

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Low-cost and fluoride-free synthesis of MFI zeolite nanosheets with enhanced stability for benzene alkylation with ethanol

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Journal of Energy Chemistry 2025年第1期100卷 458-468页

作者： Peng Zhu Cun liu Yiren Yu Guoshu Gao Yumeng Zhao Xiongfu Zhang Guodong liu Guohui Yang State Key Laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology State Key Laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of Sciences

Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive structure-directing agents(SDAs), pricey raw materials, and eco-unfriendly fluorine-containing additives. Here, we contributed a cost-effective and fluoride-free synthesis method for synthesizing high-quality MFI zeolite nanosheets through a Silicalite-1(Sil-1) seed suspension and urea cooperative strategy, only with inexpensive colloidal silica as the Si source. Our approach was effective for synthesizing both Sil-1 and aluminum-containing ZSM-5 nanosheets. By optimizing key synthesis parameters,including seed aging time, seed quantity, and urea concentration, we achieved precise control over the crystal face aspect ratio and b-axis thickness. We also revealed a non-classical oriented nanosheet growth mechanism, where Sil-1 seeds induced the formation of quasi-ordered precursor particles, and the(010)crystal planes of these particles facilitated urea adsorption, thereby promoting c-axis-oriented *** obtained ZSM-5 nanosheets exhibited exceptional catalytic performance in the benzene alkylation with ethanol, maintaining stability for over 500 h, which is 5 times longer than traditional ZSM-5 catalysts. Furthermore, large-scale production of ZSM-5 nanosheets was successfully carried out in a 3 L highpressure autoclave, yielding samples consistent with those from laboratory-scale synthesis. This work marks a significant step forward in the sustainable and efficient production of MFI nanosheets using inexpensive and environmentally friendly raw materials, offering the broad applicability in catalysis.

关键词： Aspect ratio

The role of axon guidance molecules in the pathogenesis of epilepsy

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Neural Regeneration Research 2025年第5期20卷 1244-1257页

作者： Zheng liu Chunhua Pan Hao Huang Department of Neurology Affiliated Hospital of Zunyi Medical UniversityZunyiGuizhou ProvinceChina

Current treatments for epilepsy can only manage the symptoms of the condition but cannot alter the initial onset or halt the progression of the disease. Consequently, it is crucial to identify drugs that can target novel cellular and molecular mechanisms and mechanisms of action. Increasing evidence suggests that axon guidance molecules play a role in the structural and functional modifications of neural networks and that the dysregulation of these molecules is associated with epilepsy susceptibility. In this review, we discuss the essential role of axon guidance molecules in neuronal activity in patients with epilepsy as well as the impact of these molecules on synaptic plasticity and brain tissue remodeling. Furthermore, we examine the relationship between axon guidance molecules and neuroinflammation, as well as the structural changes in specific brain regions that contribute to the development of epilepsy. Ample evidence indicates that axon guidance molecules, including semaphorins and ephrins, play a fundamental role in guiding axon growth and the establishment of synaptic connections. Deviations in their expression or function can disrupt neuronal connections, ultimately leading to epileptic seizures. The remodeling of neural networks is a significant characteristic of epilepsy, with axon guidance molecules playing a role in the dynamic reorganization of neural circuits. This, in turn, affects synapse formation and elimination. Dysregulation of these molecules can upset the delicate balance between excitation and inhibition within a neural network, thereby increasing the risk of overexcitation and the development of epilepsy. Inflammatory signals can regulate the expression and function of axon guidance molecules, thus influencing axonal growth, axon orientation, and synaptic plasticity. The dysregulation of neuroinflammation can intensify neuronal dysfunction and contribute to the occurrence of epilepsy. This review delves into the mechanisms associated with

关键词： axon guidance drug-resistant epilepsy epilepsy nerve regeneration nervous system diseases neural pathways neuroinflammatory diseases neuronal plasticity neurons synaptic remodeling

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Manufacture the conducting polymer with light

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Science China Chemistry 2025年第1期68卷 8-9页

作者： Yang Li Tianyu Li Yan Ji Baoguang liu College of Electronic and Optical Engineering & College of Flexible Electronics (Future Technology) Nanjing University of Posts & Telecommunications

Poly(3,4-ethylenedioxythiophene) (PEDOT), heralded as the “king” of conducting polymers, is esteemed in bioelectronics for its mixed electronic and ionic conductivity, mechanical properties compatible with biological tissues, tunable healing ability and stability in diverse environments [1]. Based on additive manufacturing of three-dimensional structures,PEDOT realizes the implementation in the efficient production of flexible bioelectronics, the construction of intricate electrode-neural implantations, and the development of smart brain-computer-interfaces [2].

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SnO高压结构稳定性和电学性能研究

光谱学与光谱分析 2025年第1期45卷 82-87页

作者：刘涛黄宇轩高金金王世霞上海理工大学材料与化学学院上海200093

近年来氧化亚锡(SnO)在光、电等方面的应用日益广泛,为了拓宽SnO的应用范围,采用拉曼光谱原位测试和第一性原理计算对高压条件下SnO的结构性能和电子性质进行研究。SnO表征结果:扫描电子显微镜结果显示,所选取SnO样品为具有横向尺寸的... 详细信息

近年来氧化亚锡(SnO)在光、电等方面的应用日益广泛,为了拓宽SnO的应用范围,采用拉曼光谱原位测试和第一性原理计算对高压条件下SnO的结构性能和电子性质进行研究。SnO表征结果:扫描电子显微镜结果显示,所选取SnO样品为具有横向尺寸的片状堆叠,整体呈花状;X射线衍射图谱表明,SnO样品在常温常压下晶体结构为四方晶系结构(空间群P4/nmm)。采用Mao-Bell型金刚石压腔结合原位拉曼光谱探究了SnO样品在高压下的结构性能变化,结果显示:SnO在常压有四种拉曼振动模式(A_(1g)、B_(1g)、E_(1g)和E_(2g)),分别位于211、350、113和460 cm^(-1)波数附近,其中113和211 cm^(-1)为SnO拉曼特征峰。随SnO样品体系加压至12.5 GPa,压力使Sn分子间和原子间距不断减小,导致Sn-O键长缩短,当原子发生伸缩振动时,缩短的键长使得键能增大,因此活性拉曼振动模(E_(1g)和A_(1g))均向高频方向移动;随着体系压力的继续增大,晶格发生畸变进而使得非弹性散射强度降低,峰型宽化;当加压至8 GPa时,125和216 cm^(-1)附近振动模峰急剧减小;加压至10 GPa时两个特征峰完全消失,在非静水压环境下8~10 GPa时该物质发生了非晶化;当体系加压至12.5 GPa时,谱图中仍未出现新峰,表明高压下非晶化状态稳定。随后体系进行卸压,卸压至3 GPa后SnO的E_(1g)和A_(1g)模重新出现表明样品恢复低压下的晶体结构,卸至常压特征峰强度明显分别为110和209 cm^(-1)处与加压前吻合,证明了SnO高压相变行为具有可逆性。为进一步了解压力对SnO电学性能影响,使用第一性原理方法计算了SnO在常压和实验非晶化压力(8 GPa)下的电子性质,通过非晶化前后SnO的带隙宽度变化,探究压力对SnO导电性能的影响。结果显示,在常压下SnO为具有0.43 eV带隙的间接带隙半导体,在费米能级附近态密度没有发生重叠,8 GPa时SnO显示金属性质,由于SnO O-p、Sn-s和Sn-p轨道的态密度在费米能级处重叠,导致带隙的闭合,材料发生金属化。研究结果表明SnO高压下可能产生非晶化及压力所导致的非晶化行为可逆,同时高压导致SnO发生半导体到金属的转变,拓展了SnO高压结构和电学性质的探究,为SnO高压下的应用提供进一步帮助。

关键词： SnO 拉曼光谱金刚石压腔第一性原理电子性质

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PI3K/AKT signaling and neuroprotection in ischemic stroke:molecular mechanisms and therapeutic perspectives

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Neural Regeneration Research 2025年第10期20卷 2758-2775页

作者： Tianlong liu Xiaolin Li Xiaowei Zhou Wei Chen Aidong Wen Minna liu Yi Ding Department of Pharmacy Xijing HospitalFourth Military Medical UniversityXi’anShaanxi ProvinceChina Department of Pharmacy The 940 Hospital of Joint Logistics Support Forces of Chinese PLALanzhouGansu ProvinceChina Department of Pharmacy The 944 Hospital of Joint Logistics Support Forces of Chinese PLAJiuquanGansu ProvinceChina Department of Nephrology The 940 Hospital of Joint Logistics Support Forces of Chinese PLALanzhouGansu ProvinceChina

It has been reported that the PI3K/AKT signaling pathway plays a key role in the pathogenesis of ischemic *** a result,the development of drugs targeting the PI3K/AKT signaling pathway has attracted increasing attention from *** article reviews the pathological mechanisms and advancements in research related to the signaling pathways in ischemic stroke,with a focus on the PI3K/AKT signaling *** key findings include the following:(1)The complex pathological mechanisms of ischemic stroke can be categorized into five major types:excitatory amino acid toxicity,Ca^(2+)overload,inflammatory response,oxidative stress,and apoptosis.(2)The PI3K/AKT-mediated signaling pathway is closely associated with the occurrence and progression of ischemic stroke,which primarily involves the NF-κB,NRF2,BCL-2,mTOR,and endothelial NOS signaling pathways.(3)Natural products,including flavonoids,quinones,alkaloids,phenylpropanoids,phenols,terpenoids,and iridoids,show great potential as candidate substances for the development of innovative anti-stroke medications.(4)Recently,novel therapeutic techniques,such as electroacupuncture and mesenchymal stem cell therapy,have demonstrated the potential to improve stroke outcomes by activating the PI3K/AKT signaling pathway,providing new possibilities for the treatment and rehabilitation of patients with ischemic *** investigations should focus on the direct regulatory mechanisms of drugs targeting the PI3K/AKT signaling pathway and their clinical translation to develop innovative treatment strategies for ischemic stroke.

关键词： apoptosis autophagy inflammation ischemic stroke neuroprotection oxidative stress pathogenesis phosphatidylinositol 3-kinase protein kinase B therapeutics

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