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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
文摘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.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 11205103 and 11075202)
文摘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.
基金study was supported by the STI2030-Major Projects(Grant No.2021ZD0201003)the National Natural Science Foundation of China(Grant Nos.31830035,31771156,21921004,and 32100899)+3 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB32030200)the Shenzhen Key Laboratory of Viral Vectors for Biomedicine(Grant No.ZDSYS20200811142401005)the Key Laboratory of Quality Control Technology for Virus-Based Ther-apeutics,Guangdong Provincial Medical Products Administration(Grant No.2022ZDZ13)Open Project Program of Wuhan National Laboratory for Optoelectronics(Grant No.2019WNLOKF022).
文摘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.
基金supported by grants from the National Key R&D Program of China(2017YFE0103400)the National Nature Science Foundation of China(81470628).
文摘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.
基金supported by the Natural Science Foundation of Jiangsu Province (BK20151380)NSF of China (21103087 and 21872067)supported by the Fundamental Research Funds for the Central Universities (020514380116)。
文摘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.
基金The authors thank for National Natural Science Foundation of China(U1710106)for financial support.
文摘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.
基金supported by the National Natural Science Foundation of China, Nos.31830035, 91732304, 91632303, 81661148053, and 31771156(all to FQX)the Key-Area Research and Development Program of Guangdong Province of China, No.2018B030331001(to FQX)+4 种基金the SIAT Innovation Program for Excellent Young Researchers of China,No.E1G023(to FJ)the Guangdong Basic and Applied Basic Research Foundation of China, No.2021A1515011235(to FQX)Shenzhen Key Laboratory of Viral Vectors for Biomedicine of China, No.ZDSYS20200811142401005(to FQX)the National Basic Research Program(973 Program)of China, No.2015CB755600(to FQX)the Strategic Priority Research Program(B)of China, No.XDB32030200(to FQX)
文摘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.
基金Supported by the National Key Research and Development Program of China(Grant No.2018YFC0115000)the National Natural Science Foundation of China(Grant No.21603267)the Chinese Academy of Sciences(Grant No.YZ201677 and YZ201551)。
文摘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.
基金the National Natural Science Foundation of China(Grants,22161132028,221721177,22127801,U1932218 and 21733013)Hubei Provincial Natural Science Foundation(2021CFA021)Youth Innovation Promotion Association,Chinese Academy of Sciences(2019326)。
文摘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.
基金This review was supported by the National Science and Technology Innovation 2030(2021ZD0201003)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB32030200)+1 种基金the National Natural Science Foundation of China(31830035)the Shenzhen Key Laboratory of Viral Vectors for Biomedicine(ZDSYS20200811142401005).
文摘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.
基金the National Basic Research Program(973 Program)of China(2015CB755601)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB32030200)+1 种基金the National Natural Science Foundation of China(31771156,81661148053,91632303,31800885,31500868,31671120 and 91732304)the China Postdoctoral Science Foundation(2019M653118 and 2018M632946).
文摘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.
基金supported by the National Key Research and Development Program of China(2017YFB0307303)the National Nature Science Foundation of China(21625101,21521005)the Fundamental Research Funds for the Central Universities(XK1802-6,XK1803-05,XK1902,12060093063)。
文摘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.
基金Acknowledgements This work was supported by the National Natural Science Foundation of China under Grant Nos. 11075202 and 11475253.
文摘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.
基金grateful for the financial support from the National Natural Science Foundation of China(No.22271083)the Open Project Funding of the State Key Laboratory of Biocatalysis and Enzyme Engineering(No.SKLBEE2021026)the Innovation and Entrepreneurship Training Program for Undergraduates of Hubei University(No.X202210512001).
文摘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.
文摘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.
基金supported by the National Natural Science Foundation of China(grant number 81473192)the National Basic Research Program of China(grant number 2010CB529802)
文摘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.
文摘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.
基金The authors would like to thank the financial support from the National Major Basic Research Program of China (No. 2013CB910200) and the National Natural Science Foundation of China (Nos. 21120102038, 81227902, 21475146, 21221064, 20875098 and 21075132).
文摘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.
基金supported by the National key of R&D Program of China(No.2018YFC0115000)the National Major Scientific Research Equipment Development Project of China(No.81627901)+3 种基金the Chinese Academy of Sciences(Nos.YZ201677,YZ201551,KFJ-STS-QYZD-169)the National Natural Science Foundation of China(No.11575287,11705274)Major Scientific and Technological Innovation Project in Hubei(No.2019AAA023)Application Foundation Frontier Project of WuHan(No.2019020701011450).
文摘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.