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Anatomical Evidence for the Neural Connection from the Emotional Brain to Autonomic Innervation in the Anterior Chamber Structures of the Eye
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作者 Lin MA Fang YANG +7 位作者 Qing LIU Xu-tao ZHU Xin LIU Sen JIN Hua-dong WANG Lei PEI Fu-qiang XU Hai-xia LIU 《Current Medical Science》 SCIE CAS 2022年第2期417-425,共9页
Objective Previous studies have shown that the autonomic nervous system(ANS),which can be affected by emotions,is important in the occurrence or progression of glaucoma.The autonomic innervation distributed in the ant... Objective Previous studies have shown that the autonomic nervous system(ANS),which can be affected by emotions,is important in the occurrence or progression of glaucoma.The autonomic innervation distributed in the anterior chamber(AC)structures might play an efferent role in the neural regulation of intraocular pressure(IOP).This study aimed to investigate the anatomic neural connection from the emotional brain to autonomic innervation in the AC.Methods A retrograde trans-multisynaptic pseudorabies virus encoded with an enhanced green fluorescent protein(PRV531)and non-trans-synaptic tracer FAST Dil were injected into the right eye of mice,respectively.Fluorescent localization in the emotional brain and preganglionic nuclei was studied.Five and a half days after PRV531 injection into the right AC,fluorescent signals were observed in several emotional brain regions,including the amygdala,agranular insular cortex,lateral septal nuclei,periaqueductal gray,and hypothalamus.Autonomic preganglionic nuclei,including Edinger-Westphal nucleus,superior salivatory nucleus,and intermediolateral nucleus,were labeled using PRV531.Results The sensory trigeminal nuclei were not labeled using PRV531.The fluorescence signals in the nuclei mentioned above showed bilateral distribution,primarily on the ipsilateral side.Seven days after injecting FAST Dil into the AC,we observed no FAST Dil-labeled neurons in the central nervous system.Conclusion Our results indicate a neural connection from the emotional brain to autonomic innervation in the AC,which provides anatomical support for the emotional influence of IOP via the ANS. 展开更多
关键词 intraocular pressure emotional brain AMYGDALA anterior chamber autonomic innervation
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High frequency forcing on nonlinear systems
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作者 姚成贵 何志威 占萌 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第3期209-218,共10页
High-frequency signals are pervasive in many science and engineering fields.In this work,the effect of high-frequency driving on general nonlinear systems is investigated,and an effective equation for slow motion is d... High-frequency signals are pervasive in many science and engineering fields.In this work,the effect of high-frequency driving on general nonlinear systems is investigated,and an effective equation for slow motion is derived by extending the inertial approximation for the direct separation of fast and slow motions.Based on this theory,a high-frequency force can induce various phase transitions of a system by changing its amplitude and frequency.Numerical simulations on several nonlinear oscillator systems show a very good agreement with the theoretic results.These findings may shed light on our understanding of the dynamics of nonlinear systems subject to a periodic force. 展开更多
关键词 high frequency nonlinear oscillator inertial approximation phase transitions
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Brain-wide N2cG compensation permits glycoprotein-deleted rabies virus to trace neural circuits across multiple synapses 被引量:1
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作者 Nengsong Luo Zengpeng Han +5 位作者 Jiaxin Kou Yuxiang Cai Xin Yang Jie Wang Kunzhang Lin Fuqiang Xu 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2023年第6期13-21,共9页
Rabies-viruses-based retrograde tracers can spread across multiple synapses in a retrograde direction in the nervous system of rodents and primates,making them powerful tools for determining the structure and function... Rabies-viruses-based retrograde tracers can spread across multiple synapses in a retrograde direction in the nervous system of rodents and primates,making them powerful tools for determining the structure and function of the complicated neural circuits of the brain.However,they have some limitations,such as posing high risks to human health and the inability to retrograde trans-synaptic label inputs from genetically-de¯ned starter neurons.Here,we established a new retrograde trans-multi-synaptic tracing method through brain-wide rabies virus glycoprotein(RVG)compensation,followed by glycoprotein-deleted rabies virus(RV-△G)infection in specific brain regions.Furthermore,in combination with the avian tumor virus receptor A(TVA)controlled by a cell-type-specific promoter,we found that EnvA-pseudotyped RV-△G can mediate e±cient retrograde trans-multi-synaptic transduction from cell-type-specific starter neurons.This study provides new alternative methods for neuroscience researchers to analyze the input neural networks of rodents and nonhuman primates. 展开更多
关键词 Rabies virus retrograde tracers trans-multi-synaptic tracing AAV-PHP.eB celltype-specific input neural networks
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A Non-canonical Excitatory PV RGC–PV SC Visual Pathway for Mediating the Looming-evoked Innate Defensive Response
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作者 Man Yuan Sen Jin +4 位作者 Gao Tan Siyuan Song Yizong Liu Huadong Wang Yin Shen 《Neuroscience Bulletin》 SCIE CAS CSCD 2024年第3期310-324,共15页
Parvalbumin-positive retinal ganglion cells(PV+RGCs)are an essential subset of RGCs found in various species.However,their role in transmitting visual information remains unclear.Here,we characterized PV+RGCs in the r... Parvalbumin-positive retinal ganglion cells(PV+RGCs)are an essential subset of RGCs found in various species.However,their role in transmitting visual information remains unclear.Here,we characterized PV+RGCs in the retina and explored the functions of the PV+RGC-mediated visual pathway.By applying multiple viral tracing strategies,we investigated the downstream of PV+RGCs across the whole brain.Interestingly,we found that the PV+RGCs provided direct monosynaptic input to PV+excitatory neurons in the superficial layers of the superior colliculus(SC).Ablation or suppression of SC-projecting PV+RGCs abolished or severely impaired the flight response to looming visual stimuli in mice without affecting visual acuity.Furthermore,using transcriptome expression profiling of individual cells and immunofluorescence colocalization for RGCs,we found that PV+RGCs are predominant glutamatergic neurons.Thus,our findings indicate the critical role of PV+RGCs in an innate defensive response and suggest a non-canonical subcortical visual pathway from excitatory PV+RGCs to PV+SC neurons that regulates looming visual stimuli.These results provide a potential target for intervening and treating diseases related to this circuit,such as schizophrenia and autism. 展开更多
关键词 Parvalbumin-positive retinal ganglion cell Innate fear Superior colliculus Excitatory-excitatory neuronal connection Looming-evoked defensive response Subcortical pathway
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Adjacent acid sites cooperatively catalyze fructose to 5-hydroxymethylfurfural in a new, facile pathway 被引量:1
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作者 Xia Yu Yueying Chu +7 位作者 Lei Zhang Hui Shi Mingjiang Xie Luming Peng Xuefeng Guo Wei Li Nianhua Xue Weiping Ding 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第8期112-117,I0004,共7页
To study the effect of adjacent hydroxyl to the active sites, several acid catalysts, i.e. substituted benzoic acids with adjacent carboxyl are employed in the fructose dehydration to 5-hydroxymethylfurfural(HMF).Expe... To study the effect of adjacent hydroxyl to the active sites, several acid catalysts, i.e. substituted benzoic acids with adjacent carboxyl are employed in the fructose dehydration to 5-hydroxymethylfurfural(HMF).Experimental results reveal that Br?nsted acid sites with adjacent carboxyl present higher catalytic ability than isolated ones. Computational results suggest that the adjacent sites lead to co-interaction on fructose, corresponding more stable transition state and faster HMF formation rate. Based on the enhancement from the adjacent sites, a novel ordered mesoporous carbon(OMC) full of carboxyls in surface is prepared and turns out to be an effective solid catalyst for HMF production from fructose derived from biomass. 展开更多
关键词 Fructose dehydration Adjacent sites Cooperative catalysis 5-HYDROXYMETHYLFURFURAL
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Utilizing 3D DOSY NMR in the characterization of organic compounds in coal chemical wastewater 被引量:1
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作者 Hui Ma Christian M.Pedersen +4 位作者 Qi Zhao Shiyu Jia Bin Yuan Xianglin Hou Yingxiong Wang 《Magnetic Resonance Letters》 2022年第2期69-79,I0002,共12页
Coal chemical wastewater(CCW)with the features of high toxicity and poor biodegradability is a big issue in environmental remediation,posing a great threat to aquatic ecosystems and to human beings.Such complex molecu... Coal chemical wastewater(CCW)with the features of high toxicity and poor biodegradability is a big issue in environmental remediation,posing a great threat to aquatic ecosystems and to human beings.Such complex molecular mixtures are notoriously difficult to characterize without initial physical separation.Herein,we present the 3D diffusion ordered spectroscopy(DOSY)analysis for CCW using DOSY-COSY and DOSY-HSQC methods,the advantages of this strategy have been demonstrated in the analysis of mixtures of aliphatic oxygenates and aromatic compounds,before being implemented on a genuine CCW sample in this study.The results showed that 3D DOSY is a robust and reliable tool for providing superior resolution and virtual separation of complex pollutants,and can be used as a general approach for structural elucidation. 展开更多
关键词 Coal chemical wastewater 3D DOSY NMR ANALYSIS SEPARATION Structural characterization
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A new anterograde trans-synaptic tracer based on Sindbis virus
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作者 Xiang-Wei Shi Fan Jia +1 位作者 Pei Lyu Fu-Qiang Xu 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第12期2761-2764,共4页
Mapping neural circuits is critical for understanding the structure and function of the nervous system.Engineered viruses are a valuable tool for tracing neural circuits.However,current tracers do not fully meet the n... Mapping neural circuits is critical for understanding the structure and function of the nervous system.Engineered viruses are a valuable tool for tracing neural circuits.However,current tracers do not fully meet the needs for this approach because of various drawbacks,such as toxicity and characteristics that are difficult to modify.Therefore,there is an urgent need to develop a new tracer with low toxicity and that allows for long-term studies.In this study,we constructed an engineered Sindbis virus(SINV)expressing enhanced green fluorescent protein(EGFP)reporter gene(SINV-EGFP)and found that it had no significant difference in biological characterization compared with the wild-type Sindbis virus in BHK-21 cells and neurons in vitro.We injected the virus into the visual circuit of mouse brain and found that the virus infected neurons in the local injected site and anterogradely spread in the neural circuits.Although the efficiency of transmission was limited,the findings demonstrate that SINV can be used as a new anterograde tracer to map neural circuits in mouse brain and that it spreads exclusively in the anterograde direction.Further,use of SINV in mouse brain research will provide longer time windows for circuit tracing than is possible with herpes simplex virus and vesicular stomatitis virus tracers. 展开更多
关键词 ANTEROGRADE lateral geniculate nucleus mouse brains neural circuit NEURONS RETINA Sindbis virus superior colliculus SYNAPSE TRACER
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Li Plating on Carbon Electrode Surface Probed by Low-Field Dynamic Nuclear Polarization ^(7)Li NMR
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作者 张哲恺 田季宇 +4 位作者 陈俊飞 贺玉贵 刘朝阳 梁欣苗 冯继文 《Chinese Physics Letters》 SCIE EI CAS CSCD 2021年第12期33-37,共5页
Lithium deposition on graphite electrode not only reduces fast-charging capability of lithium ion batteries but also causes safety trouble.Here,a low-field^(7)Li dynamic nuclear polarization(DNP)is used to probe Li pl... Lithium deposition on graphite electrode not only reduces fast-charging capability of lithium ion batteries but also causes safety trouble.Here,a low-field^(7)Li dynamic nuclear polarization(DNP)is used to probe Li plating on the surfaces of three types of carbon electrodes:hard carbon,soft carbon and graphite.Owing to the strong Fermi contact interaction between^(7)Li and conduction electrons,the^(7)Li nuclear-magnetic-resonance(NMR)signal of Li metal deposited on electrode surface could be selectively enhanced by DNP.It is suggested that low-field^(7)Li DNP spectroscopy is a sensitive tool for investigating Li deposition on electrodes during charging/discharging processes. 展开更多
关键词 NMR ELECTRODE CHARGING
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Heteronuclear-filtered ^(1)H homonuclear multi-quantum correlation experiment at 100 kHz magic-angle spinning Dedicated to Professor Chaohui Ye on the occasion of his 80th birthday
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作者 Mingji Zheng Shuangqin Zeng +4 位作者 Xiumei Wang Xiuzhi Gao Qiang Wang Jun Xu Feng Deng 《Magnetic Resonance Letters》 2022年第4期266-275,共10页
Remarkable advances in fast magic-angle spinning(MAS)techniques significantly improve the resolution of^(1)H solid-state nuclear magnetic resonance(NMR)spectra.Here,we introduce a heteronuclear-filtered^(1)H homonucle... Remarkable advances in fast magic-angle spinning(MAS)techniques significantly improve the resolution of^(1)H solid-state nuclear magnetic resonance(NMR)spectra.Here,we introduce a heteronuclear-filtered^(1)H homonuclear multi-quantum(MQ)correlation strategy available at a MAS rate of 100 kHz by combining^(1)H{X}heteronuclear-filtered methods and^(1)H homonuclear MQ correlation experiments.The proposed strategy was applied to selectively extract^(1)H signals of aluminum lactate(Al-Lac)in a mixture of Al-Lac and zinc lactate(Zn-Lac)using 27Al-filtered methods(i.e.,^(1)H{27Al}heteronuclear multiple quantum correlation(HMQC)or^(1)H{27Al}symmetry-based resonance-echo saturationpulse double-resonance(S-RESPDOR)).We demonstrate that incorporating these 27Al-filtered methods into two-dimensional(2D)^(1)He^(1)H double-quantum(DQ)/single-quantum(SQ),triple-quantum(TQ)/SQ,and even three-dimensional(3D)27Al/^(1)H(DQ)/^(1)H(SQ)experiments can facilitate the acquisition of spectra without signal overlap and targeted characterization of the^(1)H species surrounding 27Al sites.The proposed strategy is considered to efficiently extract key structural information from complex spin systems. 展开更多
关键词 Solid-state NMR spectroscopy Proton Heteronuclear filter Homonuclear correlation Multi-quantum Ultra-fast magic angle spinning
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Viral Tools for Neural Circuit Tracing 被引量:5
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作者 Qing Liu Yang Wu +2 位作者 Huadong Wang Fan Jia Fuqiang Xu 《Neuroscience Bulletin》 SCIE CAS CSCD 2022年第12期1508-1518,共11页
Neural circuits provide an anatomical basis for functional networks.Therefore,dissecting the structure of neural circuits is essential to understanding how the brain works.Recombinant neurotropic viruses are important... Neural circuits provide an anatomical basis for functional networks.Therefore,dissecting the structure of neural circuits is essential to understanding how the brain works.Recombinant neurotropic viruses are important tools for neural circuit tracing with many advantages over non-viral tracers:they allow for anterograde,retrograde,and trans-synaptic delivery of tracers in a cell type-specific,circuit-selective manner.In this review,we summarize the recent developments in the viral tools for neural circuit tracing,discuss the key principles of using viral tools in neuroscience research,and highlight innovations for developing and optimizing viral tools for neural circuit tracing across diverse animal species,including nonhuman primates. 展开更多
关键词 Neural circuit Viral tool ANTEROGRADE RETROGRADE Trans-synaptic
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Rabies Virus Pseudotyped with CVS-N2C Glycoprotein as a Powerful Tool for Retrograde Neuronal Network Tracing 被引量:2
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作者 Xutao Zhu Kunzhang Lin +13 位作者 Qing Liu Xinpei Yue Huijie Mi Xiaoping Huang Xiaobin He Ruiqi Wu Danhao Zheng Dong Wei Liangliang Jia Weilin Wang Anne Manyande Jie Wang Zhijian Zhang Fuqiang Xu 《Neuroscience Bulletin》 SCIE CAS CSCD 2020年第3期202-216,共15页
Efficient viral vectors for mapping and manipulating long-projection neuronal circuits are crucial in structural and functional studies of the brain. The SAD strain rabies virus with the glycoprotein gene deleted pseu... Efficient viral vectors for mapping and manipulating long-projection neuronal circuits are crucial in structural and functional studies of the brain. The SAD strain rabies virus with the glycoprotein gene deleted pseudotyped with the N2 C glycoprotein(SAD-RV(DG)-N2 C(G)) shows strong neuro-tropism in cell culture, but its in vivo efficiency for retrograde gene transduction and neuro-tropism have not been systematically characterized.We compared these features in different mouse brain regions for SAD-RV-N2 C(G) and two other widely-used retrograde tracers, SAD-RV(DG)-B19(G) and r AAV2-retro. We found that SAD-RV(DG)-N2 C(G) enhanced the infection efficiency of long-projecting neurons by^10 times but with very similar neuro-tropism, compared with SAD-RV(DG)-B19(G). On the other hand, SAD-RV(DG)-N2 C(G) had an infection efficiency comparable with r AAV2-retro, but a more restricted diffusion range, and broader tropism to different types and regions of longprojecting neuronal populations. These results demonstrate that SAD-RV(DG)-N2 C(G) can serve as an effective retrograde vector for studying neuronal circuits. 展开更多
关键词 VIRAL vector N2C GLYCOPROTEIN NEURONAL circuits RETROGRADE TRACING
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Covalently tethering disulfonic acid moieties onto polyoxometalate boosts acid strength and catalytic performance for hydroxyalkylation/alkylation reaction 被引量:1
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作者 Lifei Lian Yubing Liu +6 位作者 Xianfeng Yi Hanbin Hu Xiang Chen Hongqiang Li Wei Chen Anming Zheng Yu-Fei Song 《Science China Chemistry》 SCIE EI CSCD 2022年第4期699-709,共11页
Solid acid catalysts are widely used in the production of various high-value added and industrially important chemicals.Although the use of organosilicon compounds to modify the vacancy site has been extensively studi... Solid acid catalysts are widely used in the production of various high-value added and industrially important chemicals.Although the use of organosilicon compounds to modify the vacancy site has been extensively studied,the covalent tethering-SO_(3)H functionalized organosilicon modified polyoxometalates(POMs)has been rarely reported.In this work,two catalysts(TBA_(4)[SiW_(11)O_(39)(O(SiC_(3)H_(6)SO_(3)H)_(2))](compound 2)and TBA_(4)[SiW_(11)O_(39)(O(SiC_(8)H_(8)SO_(3)H)_(2))](compound 3))were synthesized successfully through covalently grafting different sulfonic acid(-SO_(3)H)groups onto[SiW_(11)O_(39)]^(8−)cluster,respectively.Compound 2 was achieved by surface grafting and in situ oxidation(3-mercaptopropyl)-trimethoxysilane,while compound 3 was achieved by surface grafting of 2-(4-chlorosulfonylphenyl)ethyltrimethoxysilane.Strong Brønsted acid strength of compounds 2 and 3 can be demonstrated by different methods including potentiometric titration,pyridine adsorption studies,and the ^(31)P trimethylphosphine oxides(TMPO)nuclear magnetic resonance(NMR).The systematic investigation of the relationship among POM structures,acid strength,and electron density was carried out based on density functional theory(DFT)calculation and experimental results,which revealed that covalent modification of compounds 2 and 3 decreased the electron density of the O-H bond,and promoted the release of H^(+).When applied in hydroxyalkylation/alkylation(HAA)reaction of 2-methylfuran(2-MF)with cyclohexanone,compound 2 exhibited better catalytic performance with conversion of ~93%,monocyclic fuel precursors(1a)yield of 79.9% and selectivity of 85.7% than compound 3,which can be attributed to strong Brønsted acid and the intramolecular hydrogen-bonding interactions between the neighboring -SO_(3)H moieties in compound 2.Finally,compound 2 also showed excellent catalytic activity in the HAA reaction of 2-MF with several different aldehydes and ketones(e.g.,furfuraldehyde,5-methylfurfuraldehyde,acetone,butyraldehyde and 4-methoxybenzaldehyde).This result opens a new pathway for design and fabrication of novel solid acid catalysts. 展开更多
关键词 POLYOXOMETALATES sulfonic acid covalent modifications acid catalysis alkylation reaction
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Optimal configuration for vibration frequencies in a ring of harmonic oscillators: The nonidentical mass effect 被引量:1
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作者 Shuai Liu Guo-Yong Zhang +1 位作者 Zhiwei He Meng Zhan 《Frontiers of physics》 SCIE CSCD 2015年第3期89-100,共12页
The parameter diversity effect in coupled nonidentical elements has attracted persistent interest in nonlinear dynamics. Of fundamental importance is the so-called optimal configuration problem for how the spatial pos... The parameter diversity effect in coupled nonidentical elements has attracted persistent interest in nonlinear dynamics. Of fundamental importance is the so-called optimal configuration problem for how the spatial position of elements with different parameters precisely determines the dynamics of the whole system. In this work, we study the optimal configuration problem for the vibration spectra in the classical mass-spring model with a ring configuration, paying particular attention to how the configuration of different masses affects the second smallest vibration frequency (ω2) and the largest one (ωN). For the extreme values of ω2 and ωN, namely, (ω2)min, (ω2)max, (ωN)min, and (ωN)max, we find some explicit organization rules for the optimal configurations and some approximation rules when the explicit organization rules are not available. The different distributions of ω2 and ωN are compared. These findings are interesting and valuable for uncovering the underlying mechanism of the parameter diversity effect in more general cases. 展开更多
关键词 SYNCHRONIZATION vibration frequencies normal modes complex systems
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Cu(OAc)_(2)-Mediated Synthesis of Fullerodihydropyridine-3-ones via the Reaction of[60]Fullerene with β-Substituted Ethylamines in the Absence or Presence of Arylacetaldehydes
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作者 Xiu-Shan Liu Hui-Juan Wang +6 位作者 Fei-Lun Wu Jing-Wen Huo Xing-Yu Wang Fa-Bao Li Rui Sun Li Liu Chao-Yang Liu 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2023年第13期1557-1565,共9页
A series of unreported fullerodihydropyridine-3-ones were synthesized as a new family of fullerene derivatives in moderate to good yields by a simple one-step reaction of[60]fullerene with cheap and readily available ... A series of unreported fullerodihydropyridine-3-ones were synthesized as a new family of fullerene derivatives in moderate to good yields by a simple one-step reaction of[60]fullerene with cheap and readily available β-substituted ethylamines in the absence or presence of arylacetaldehydes under the assistance of Cu(OAc)_(2).The in situ generation of arylacetaldehydes by the C—N bond cleavage of arylethylamines avoided their complex synthesis in advance and realized the preparation of fullerodihydropyridine-3-ones with structural and functional diversities,which may have promising applications in perovskite solar cells to improve the performance of photovoltaic devices due to the existence of a largeπ-conjugated system on the dihydropyridine-3-one ring. 展开更多
关键词 FULLERENES Copper β-Substituted ethylamines Arylacetaldehydes Fullerodihyd ropyridine-3-ones Radical reactions
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Classification of Wines Based on Combination of ^1H NMR Spectroscopy and Principal Component Analysis 被引量:3
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作者 杜媛媛 白国允 +1 位作者 张许 刘买利 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2007年第7期930-936,共7页
1H 的联合原子磁性的回声(NMR ) 光谱学和主要部件分析(PCA ) 为是为类型,生产起源或酒的地理起源的分类的一个有用方法显示出潜力。在这初步的研究, 21 装的酒为他们生产的地点被分类 / 分开在 Shacheng, Changli 和 Yantai,和混... 1H 的联合原子磁性的回声(NMR ) 光谱学和主要部件分析(PCA ) 为是为类型,生产起源或酒的地理起源的分类的一个有用方法显示出潜力。在这初步的研究, 21 装的酒为他们生产的地点被分类 / 分开在 Shacheng, Changli 和 Yantai,和混合、中等干燥、干燥白人和干燥的红酒的类型,用 NMR-PCA 方法。酒被一家企业的三个辅助公司根据一样的国家标准生产。分离被相信主要由于为不同的酒和环境变化的发酵过程,例如本地气候,土壤,地下的水,日光和降雨。与分离联系的主要化学药品被识别。 展开更多
关键词 类别 核磁共振 地理起源 主要成分分析 光谱学
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Firing rates of coupled noisy excitable elements 被引量:4
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作者 Shuai Liu Zhi-Wei He Meng Zhan 《Frontiers of physics》 SCIE CSCD 2014年第1期120-127,共8页
The dynamics of coupled excitable FitzHugh Nagumo systems under external noisy driving is studied. Different from most of previous work focusing on the noise-induced regularity in the framework of coherence resonance,... The dynamics of coupled excitable FitzHugh Nagumo systems under external noisy driving is studied. Different from most of previous work focusing on the noise-induced regularity in the framework of coherence resonance, here the average frequency (or firing rate) of coupled excitable elements is of much more concern. We find that (i) their frequencies first increase and then decrease with the increase of the coupling, and there is a clear crossover from a rush increase to a smooth increase with the increase of noise strength, and (ii) for nonidentical cases, all elements transit to an identical frequency simultaneously only after a certain coupling strength is achieved. These first-increase-thendecrease non-monotonic frequency behavior and isochronous frequency synchronization are believed to be two basic behaviors in coupled noisy excitable systems. 展开更多
关键词 coupled excitable elements firing rate noise coherence resonance
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A novel ω-conotoxin Bu8 inhibiting N-type voltage-gated calcium channels displays potent analgesic activity 被引量:2
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作者 Jinqin Chen Xinhong Liu +5 位作者 Shuo Yu Jia Liu Rongfang Chen Yunxiao Zhang Ling Jiang Qiuyun Dai 《Acta Pharmaceutica Sinica B》 SCIE CAS CSCD 2021年第9期2685-2693,共9页
ω-Conotoxins inhibit N-type voltage-gated calcium(Ca_(v)2.2)channels and exhibit efficacy in attenuating neuropathic pain but have a low therapeutic index.Here,we synthesized and characterized a novelω-conotoxin,Bu8... ω-Conotoxins inhibit N-type voltage-gated calcium(Ca_(v)2.2)channels and exhibit efficacy in attenuating neuropathic pain but have a low therapeutic index.Here,we synthesized and characterized a novelω-conotoxin,Bu8 from Conus bullatus,which consists of 25 amino acid residues and three disulfide bridges.Bu8 selectively and potently inhibits depolarization-activated Ba^(2+ )currents mediated by rat Ca_(v)2.2 expressed in HEK293 T cells(IC_(50)=89 nmol/L).Bu8 is two-fold more potent thanω-conotoxin MVIIA,aω-conotoxin currently used for the treatment of severe chronic pain.It also displays potent analgesic activity in animal pain models of hot plate and acetic acid writhing but has fewer side effects on mouse motor function and lower toxicity in goldfish.Its lower side effects may be attributed to its faster binding rate and higher recovery ratios.The NMR structure demonstrates that Bu8 contains a small irregular tripleβ-strand.The structure-activity relationships of Bu8 Ala mutants and Bu8/MVIIA hybrid mutants demonstrate that the binding mode of Ca_(v)2.2 with the amino acid residues in loop 1 and loop 2 of Bu8 is different from that of MVIIA.This study characterizes a novel,more potentω-conotoxin and provides new insights for designing Ca_(v)2.2 antagonists. 展开更多
关键词 N-type calcium ion channel ω-conotoxin Bu8 Analgesic activity Structure-activity relationship
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Solvent-Free Synthesis of ITQ-12, ITQ-13, and ITQ-17 Zeolites 被引量:2
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作者 Qinming Wu Xiaolong Liu +9 位作者 Longfeng Zhu Xiangju Meng Feng Deng Fengtao Fan Zhaochi Feng Can Li Stefan Maurer Mathias Feyen Ulrich Muller Feng-Shou Xiao 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2017年第5期572-576,共5页
Development of the sustainable routes for synthesis of ITQ-family zeolites is very important because of their unique structures and excellent catalytic and adsorptive properties.The burden of costly raw materials and ... Development of the sustainable routes for synthesis of ITQ-family zeolites is very important because of their unique structures and excellent catalytic and adsorptive properties.The burden of costly raw materials and low efficiency of synthesis put a strong challenge for their widespread commercial application.Here,we show an alternative and simple route for synthesis of ITQ-12,ITQ-13,and ITQ-17 zeolites using commercially available organic templates by a facile grinding process of anhydrous starting raw solids,followed by heating at 140-180 ℃.Compared with the conventional hydrothermal synthesis,this approach has obvious advantages such as employment of low-cost organic templates with very high effectiveness,high yield of zeolite products,short crystallization time,and relatively simple procedures.This methodology might open a pathway to synthesize ITQ zeolites with more sustainable manner. 展开更多
关键词 ZEOLITE sustainable route solvent-free synthesis low-cost organic template ITQ-family
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Characterization and Comparison of Commercial Chinese Cereal and European Grape Vinegars Using ^1H NMR Spectroscopy Combined with Multivariate Analysis 被引量:1
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作者 Xiaohua Wang Jie Wang +4 位作者 Ghulam Mustafa Kamal Bin Jiang Peng Sun Xu Zhang Maili Liu 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2016年第11期1183-1193,共11页
A holistic and comparative quality assessment of vinegars from different countries is needed with international trade of vinegar become frequent. In this study, compounds characterization and comparison of commercial-... A holistic and comparative quality assessment of vinegars from different countries is needed with international trade of vinegar become frequent. In this study, compounds characterization and comparison of commercial-grade Chinese cereal and European grape vinegars were performed using ^1H NMR spectroscopy coupled with principal component analysis (PCA) and orthogonal projection to latent structures discriminate analysis (OPLS-DA). The results showed that Balsamic vinegars of Modena were clearly discriminated by higher amount of fructose and glucose, while Chinese aromatic vinegar and aged vinegars were characterized by higher amount of amino acids, volatile compounds, succinate and betaine. On the other hand, flavoring compounds in Chinese rice vinegar and European wine vinegars are less than the others. These characteristic components are associated with the special raw materials and producing process of each types of vinegar and endow them special flavor. The results obtained in this study provide a global insight into vinegar through a ^1H NMR based compounds analysis that allows a holistic quality assessment and comparison of vinegars from different manufacture origins. 展开更多
关键词 NMR PCA OPLS-DA CHARACTERIZATION COMPARISON VINEGAR
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−22-Fold of^(1)H signal enhancement in-situ low-field liquid NMR using nanodiamond as polarizer of overhauser dynamic nuclear polarization
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作者 Zhen Zhang Fang Chen +7 位作者 Jiwen Feng Junfei Chen Li Chen Zhi Zhang Huijuan Wang Xin Cheng Maili Liu Chaoyang Liu 《Chinese Chemical Letters》 SCIE CAS CSCD 2021年第11期3483-3486,共4页
Nanodiamond(ND)polarizer can be used for dynamic nuclear polarization(DNP),owing to unpaired electrons provided by surface defects.However,^(1)H enhancement via Overhauser DNP(ODNP)using ND in-situ liquid has been fou... Nanodiamond(ND)polarizer can be used for dynamic nuclear polarization(DNP),owing to unpaired electrons provided by surface defects.However,^(1)H enhancement via Overhauser DNP(ODNP)using ND in-situ liquid has been found much smaller than traditional radicals.Herein,we study the surface properties of ND using electron spin resonance(ESR)and Raman methods firstly.Then the enhancement of^(1)H ODNP is explored using ND as polarizer with different nanoparticle sizes and concentrations at home-built 0.06 T DNP spectrometer.The surface of ND with the size of 30 nm is further modification via high temperature air oxidized and the enhancement was measured.The results show that nanoparticle sizes and Raman peak intensity ratio of sp^(2)/sp^(3)hybridization are approximate negative correlation and positive correlation to enhancement,respectively.Furthermore,there is no significant enhancement in the oxidation group,and a−22.5-fold^(1)H ODNP enhancement is achieved in-situ liquid at room temperature,which demonstrate the ND can be used as an efficient enhancer.We expect ND to play a greater role in biomedical research,especially for multimodal imaging with improving the performance of ND surface. 展开更多
关键词 ODNP POLARIZER NANOPARTICLE Enhancement RELAXATION
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