Through adding a nonlinear self-feedback term in the evolution equations of neural network, we introduced a transiently chaotic neural network model. In order to utilize the transiently chaotic dynamics mechanism in o...Through adding a nonlinear self-feedback term in the evolution equations of neural network, we introduced a transiently chaotic neural network model. In order to utilize the transiently chaotic dynamics mechanism in optimization problem efficiently, we have analyzed the dynamical procedure of the transiently chaotic neural network model and studied the function of the crucial bifurcation parameter which governs the chaotic behavior of the system. Based on the dynamical analysis of the transiently chaotic neural network model, chaotic annealing algorithm is also examined and improved. As an example, we applied chaotic annealing method to the traveling salesman problem and obtained good results.展开更多
Plants have a perception system triggered by pathogen and pest signals to initiate defense.These signals include evolutionarily conserved molecules from microbes and insects termed pathogen/herbivore-associated molecu...Plants have a perception system triggered by pathogen and pest signals to initiate defense.These signals include evolutionarily conserved molecules from microbes and insects termed pathogen/herbivore-associated molecular patterns(PAMPs/HAMPs).Here we showed that hexaacetyl-chitohexaose(HC),an oligosaccharide from chitin,a structural component in insect exoskeletons and fungi cell walls,upregulated defense-associated genes WRKY22,GST1,RAR1,EDS1,PAL1 and NPR2,and downregulated ICS1 at 1 h after HC treatment in Sun Chu Sha mandarin leaves.The effect was transient as defense gene transcriptional changes were not observed at 18 h after the treatment.Electrical penetration graph(EPG)recordings were used to study the feeding behavior of Asian citrus psyllid(ACP)following the HC treatment.ACP is the hemipteran vector of Candidatus Liberibacter asiaticus(CLas),the pathogen associated with huanglongbing(HLB).Adult ACP displayed reduced intercellular probing,reduced xylem feeding count and duration,and increased non-probing activity on HC-treated citrus compared to controls.During an 18-h recording,percentage for total duration of xylem ingestion,phloem ingestion,intercellular probing were lower,and the percentage of nonprobing behavior was higher in HC-treated leaves than in controls.In host-selection behavior studies,HC treatment did not alter the attractiveness of citrus leaves under light or dark conditions.In addition,ACP feeding on HC-treated leaves did not show differences in mortality for up to 10 day of exposure.In summary,we report that HC induced a transient defense in citrus and an inhibitory effect on ACP feeding but did not affect host selection or the insect fitness under the tested conditions.展开更多
Under the condition that the damping factor is between zero and one, chaotic dynamics is proved to exist in one-dimensional transiently chaotic neural networks by Li-Misiurewicz theorem. This result extends the previo...Under the condition that the damping factor is between zero and one, chaotic dynamics is proved to exist in one-dimensional transiently chaotic neural networks by Li-Misiurewicz theorem. This result extends the previous result which is done under the condition that the damping factor is zero. Because the value of damping factor affects the speed of dynamical process of transiently chaotic neural networks, this result provides more complete theoretical basis for applications. Finally, two examples by numerical simulation are given to reinforce and illustrate this result.展开更多
Photosynthesis is a promising method for H_(2)O_(2)production,but its application in pure water is limited by slow oxidation kinetics and rapid photocarrier recombination of photocatalysts.Herein,a novel defective car...Photosynthesis is a promising method for H_(2)O_(2)production,but its application in pure water is limited by slow oxidation kinetics and rapid photocarrier recombination of photocatalysts.Herein,a novel defective carbon nitride photocatalyst(D-C3-xN4)containing the C vacancies and the frustrated Lewis pairs(B and N of cyano group)is designed for H_(2)O_(2)photosynthesis,and the role of C vacancies on the electron transfer mechanism during photocatalysis is systematically investigated.The D-C_(3-x)N_(4) exhibits a H_(2)O_(2)production rate of 140.1μmol·g^(-1)·h^(-1) in pure water,which is 87.6 times that of C_(3)N_(4).Such superior performance for H_(2)O_(2)photosynthesis is found to arise from the C vacancies and frustrated Lewis pairs(FLPs).The C vacancies have strong electron-trapping ability,which greatly enhances the separation of photocarriers.The C vacancies can also effectively reduce O_(2)to*OOH via a proton-coupled process,which significantly accelerates the O_(2)reduction kinetics.Meanwhile,the FLPs show an outstanding catalytic activity for H_(2)O oxidation.This study not only provides a new structure for highly active photocatalysts,but also deepens the understanding of the electron transfer mechanism of photocatalysts with trapped sites.展开更多
AAV-PHP.eB is an artificial adeno-associated virus(AAV)that crosses the blood-brain barrier and targets neurons more efficiently than other AAVs when administered systematically.While AAV-PHP.eB has been used in vario...AAV-PHP.eB is an artificial adeno-associated virus(AAV)that crosses the blood-brain barrier and targets neurons more efficiently than other AAVs when administered systematically.While AAV-PHP.eB has been used in various disease models,its cellular tropism in cerebrovascular diseases remains unclear.In the present study,we aimed to elucidate the tropism of AAV-PHP.eB for different cell types in the brain in a mouse model of ischemic stroke and evaluate its effectiveness in mediating basic fibroblast growth factor(bFGF)gene therapy.Mice were injected intravenously with AAV-PHP.eB either 14 days prior to(pre-stroke)or 1 day following(post-stroke)transient middle cerebral artery occlusion.Notably,we observed a shift in tropism from neurons to endothelial cells with post-stroke administration of AAV-PHP.eB-mNeonGreen(mNG).This endothelial cell tropism correlated strongly with expression of the endothelial membrane receptor lymphocyte antigen 6 family member A(Ly6A).Furthermore,AAV-PHP.eB-mediated overexpression of bFGF markedly improved neurobehavioral outcomes and promoted long-term neurogenesis and angiogenesis post-ischemic stroke.Our findings underscore the significance of considering potential tropism shifts when utilizing AAV-PHP.eB-mediated gene therapy in neurological diseases and suggest a promising new strategy for bFGF gene therapy in stroke treatment.展开更多
Numerous pathological states of the nervous system involve alterations in neuronal excitability and synaptic dysfunction,which depend on the function of ion channels.Due to their critical involvement in health and dis...Numerous pathological states of the nervous system involve alterations in neuronal excitability and synaptic dysfunction,which depend on the function of ion channels.Due to their critical involvement in health and disease,the search for new compounds that modulate these proteins is still relevant.Traditional medicine has long been a rich source of neuroactive compounds.For example,the indigenous Mapuche people have used the leaves and bark of the Drimys winteri tree for centuries to treat various diseases.Consequently,several studies have investigated the biological effects of compounds in Drimys winteri,highlighting sesquiterpenes such asα-humulene,drimenin,polygodial,andα-,β-,γ-eudesmol.However,there is currently no literature review focusing on the ability of these sesquiterpenes to modulate ion channels.This review summarizes the current knowledge about neuroactive compounds found in Drimys winteri,with special emphasis on their direct actions on neuronal ion channels.Several Drimys winteri sesquiterpenes modulate a diverse array of neuronal ion channels,including transient receptor potential channels,gamma-aminobutyric acid A receptors,nicotinic acetylcholine receptors,and voltage-dependent Ca^(2+)and Na^(+)channels.Interestingly,the modulation of these molecular targets by Drimys winteri sesquiterpenes correlates with their therapeutic actions.The promiscuous pharmacological profile of Drimys winteri sesquiterpenes suggests they modulate multiple protein targets in vivo,making them potentially useful for treating complex,multifactorial diseases.Further studies at the molecular level may aid in developing multitargeted drugs with enhanced therapeutic effects.展开更多
As the penetration rate of distributed energy increases,the transient power angle stability problem of the virtual synchronous generator(VSG)has gradually become prominent.In view of the situation that the grid impeda...As the penetration rate of distributed energy increases,the transient power angle stability problem of the virtual synchronous generator(VSG)has gradually become prominent.In view of the situation that the grid impedance ratio(R/X)is high and affects the transient power angle stability of VSG,this paper proposes a VSG transient power angle stability control strategy based on the combination of frequency difference feedback and virtual impedance.To improve the transient power angle stability of the VSG,a virtual impedance is adopted in the voltage loop to adjust the impedance ratio R/X;and the PI control feedback of the VSG frequency difference is introduced in the reactive powervoltage link of theVSGto enhance the damping effect.Thesecond-orderVSGdynamic nonlinearmodel considering the reactive power-voltage loop is established and the influence of different proportional integral(PI)control parameters on the system balance stability is analyzed.Moreover,the impact of the impedance ratio R/X on the transient power angle stability is presented using the equal area criterion.In the simulations,during the voltage dips with the reduction of R/X from 1.6 to 0.8,Δδ_(1)is reduced from 0.194 rad to 0.072 rad,Δf_(1)is reduced from 0.170 to 0.093 Hz,which shows better transient power angle stability.Simulation results verify that compared with traditional VSG,the proposedmethod can effectively improve the transient power angle stability of the system.展开更多
Advanced geological prediction is a crucial means to ensure safety and efficiency in tunnel construction.However,diff erent advanced geological forecasting methods have their own limitations,resulting in poor detectio...Advanced geological prediction is a crucial means to ensure safety and efficiency in tunnel construction.However,diff erent advanced geological forecasting methods have their own limitations,resulting in poor detection accuracy.Using multiple methods to carry out a comprehensive evaluation can eff ectively improve the accuracy of advanced geological prediction results.In this study,geological information is combined with the detection results of geophysical methods,including transient electromagnetic,induced polarization,and tunnel seismic prediction,to establish a comprehensive analysis method of adverse geology.First,the possible main adverse geological problems are determined according to the geological information.Subsequently,various physical parameters of the rock mass in front of the tunnel face can then be derived on the basis of multisource geophysical data.Finally,based on the analysis results of geological information,the multisource data fusion algorithm is used to determine the type,location,and scale of adverse geology.The advanced geological prediction results that can provide eff ective guidance for tunnel construction can then be obtained.展开更多
Photocatalytic hydrogen production technology is an ideal approach to addressing energy and environmental issues,with efficient charge transfer being the key to achieving high-performance hydrogen production.Ultra-thi...Photocatalytic hydrogen production technology is an ideal approach to addressing energy and environmental issues,with efficient charge transfer being the key to achieving high-performance hydrogen production.Ultra-thin CuInS_(2)nanosheets were prepared through a solvothermal method.Subsequently,metallic Ni was surface-modified onto CuInS_(2)through photo-deposition to serve as a co-catalyst.The optimized photocatalyst exhibited a hydrogen production rate of 15.5 mmol·g^(-1)·h^(-1)in water when used an ascorbic acid as hole scavenger,which is 9 times that of the original CuInS_(2).Transient absorption spectra(TAS)analysis demonstrates that the hole transfer from CuInS_(2)nanosheets to ascorbic acid,yielding a long-lived electron with a lifetime of 45.6μs.The electrons in CuInS_(2)are efficiently captured by Ni as active sites for driving hydrogen evolution.In situ TAS further indicates that ascorbic acid and Ni sites synergistically promote the electron transfer dynamics of CuInS_(2),achieving an electron transfer efficiency of 48.4%.This work provides a viable strategy for designing highly efficient photocatalysts with enhanced charge transfer.展开更多
S-scheme heterojunctions have gained widespread application in photocatalytic reactions due to their dis-tinctive carrier transport mechanism and remarkable redox capabilities.However,a significant challenge persists ...S-scheme heterojunctions have gained widespread application in photocatalytic reactions due to their dis-tinctive carrier transport mechanism and remarkable redox capabilities.However,a significant challenge persists in extending carrier lifetimes while simultaneously enhancing light absorption,both of which are essential for optimizing photocatalytic activity.Herein,we report the solvothermal synthesis of ul-trathin CdS nanosheets grown in situ on two-dimensional(2D)Ni-MOF to construct 2D/2D S-scheme heterojunctions.Comprehensive characterizations reveal that the incorporation of Ni-MOF(metal-organic framework)with ligand-to-metal charge transfer(LMCT)states not only broadens optical absorption but also significantly prolongs carrier lifetimes.This synergistic enhancement,coupled with the S-scheme charge transport mechanism,enables the composite to function as a bifunctional catalyst for photocat-alytic hydrogen production and simultaneous benzylamine coupling.The optimal system demonstrates an impressive hydrogen evolution rate of 8.5 mmol g^(-1) h^(-1) and an N-benzylidenebenzylamine yield of 4.6 mmol g^(-1) h^(-1) without requiring a cocatalyst.This work underscores the potential of integrating MOFs with LMCT states into S-scheme heterojunctions to enhance interfacial charge transfer,offering valuable insights for the design of S-scheme heterojunctions for artificial photosynthesis and related fields.展开更多
OBJECTIVE:To explore if Hewei Jiangni granule(和胃降逆颗粒,HWJNG)could regulate esophageal hypersensitivity via stromal interaction molecule 1(STIM1)/transient receptor potential vanilloid subfamily member 1(TRPV1)pat...OBJECTIVE:To explore if Hewei Jiangni granule(和胃降逆颗粒,HWJNG)could regulate esophageal hypersensitivity via stromal interaction molecule 1(STIM1)/transient receptor potential vanilloid subfamily member 1(TRPV1)pathway.METHODS:Qualitative analysis of HWJNG was analysis by high performance of liquid and gas chromatography.In vivo,animal model of non-erosive reflux disease(NERD)was established by fructose intake and restraint stress.HWJNG and Omeprazole were administered by gavage to the drug intervention group.Reflux and visceral hypersensitivity were analyzed by pathological changes,PH value test,mechanical paw withdrawal threshold,thermal withdrawal latency and mast cells(MCs)degranulation.In vitro,substance P(SP)-induced P815 cells and dorsal root ganglion(DRG)cells were cocultured.Expression in both mice and cells of STIM1,TRPV1,and esophageal visceral hypersensitivity-related gastrointestinal neurochemicals were validated by enzyme linked immunosorbent assays,quantitative realtime polymerase chain reaction(qRT-PCR)and Western blot.Moreover,overexpression and small interfering RNA against STIM1 were utilized to verify of the role of HWJNG in DRG cells.RESULTS:HWJNG significantly suppressed intercellular space widening,injury of mitochondrial,MCs degranulation,mechanical allodynia and heat neuropathic sensory and increased pH value of esophageal mucosa in NERD mice.HWJNG inhibited expression of visceral hypersensitivityrelated gastrointestinal neurochemicals in esophageal mucosa and activated P815 cells,and expression of the STIM1,TRPV1 and related neurotransmitters in DRG and DRG cells.STIM1 siRNA and HWJNG both reduced P815 cells adhesion to DRGs cells and Ca2+flow into the cytoplasmic space of DRG cells.Furthermore,HWJNG could reversed STIM1 overexpression induced upregulation of TRPV1.CONCLUSION:HWJNG suppressed intercellular space widening in NERD mice,stabilized MCs and restored neuronal hyperexcitability by regulating visceral hypersensitivity via STIM1/TRPV1 pathway.展开更多
This study discusses the benefits and challenges of well monitoring for Gulong shale oil production.It examines the Unified Transient Analysis(UTA)method,which integrates rate and pressure data to monitor changes in f...This study discusses the benefits and challenges of well monitoring for Gulong shale oil production.It examines the Unified Transient Analysis(UTA)method,which integrates rate and pressure data to monitor changes in fracture surface area and production efficiency in real-time.The UTA method allows for early detection of production impairments and provides feedback to optimize drawdown pressure,enhancing production without damaging fracture conductivity.Analysis of production data from Well A in the Daqing Oilfield demonstrates the method's efficacy,particularly in managing choke size adjustments and identifying fracture conductivity degradation.Despite its benefits,challenges such as data quality,manual data analysis,and the need for automated choke management are highlighted.The study underscores the necessity of integrating intelligent monitoring technologies and automating workflows to optimize Gulong shale oil production.展开更多
Background Cotton is an important crop providing the most natural fibers all over the world. The cotton genomics community has utilized whole genome sequencing data to construct an elite gene pool in which functional ...Background Cotton is an important crop providing the most natural fibers all over the world. The cotton genomics community has utilized whole genome sequencing data to construct an elite gene pool in which functional genes are related to agronomic traits. However, the functional validation of these genes is hindered by time-consuming and inefficient genetic transformation methods. Thus, establishing a transient transformation system of high efficiency is necessary for cotton genomics.Results To improve the efficiency of transient transformation, we used the protoplasts isolated from the etiolated cotyledon as recipient. The enzymatic digestion buffer comprised 1.5%(w/v) cellulase, 0.75%(w/v) macerozyme, and 1% hemicellulase, osmotically buffered with 0.4 mol·L^(-1) mannitol. After 5 h of dark incubation at 25℃, uniform cotton protoplasts were successfully isolated with a yield of 4.6 × 10^(6) protoplasts per gram(fresh weight) and 95% viability. We incubated 100 μL protoplasts(2.5 × 10^(5)·m L^(-1)) with 15 μg plasmid in the solution of 0.4 mol·L^(-1) mannitol and 40% PEG 4000 for 15 min, ultimately achieving an optimal transient transfection efficiency of 71.47%.Conclusions This transient system demonstrated effective utility in cellular biology research through successful applications in subcellular localization analyses, bimolecular fluorescence complementation(Bi FC) verification, and prime editing vector validation. Through systematic optimization, we established an efficient and expedited protoplast-based transient transformation system and successfully applied this platform to cotton functional genomics studies.展开更多
We demonstrate an all-optical technique for in situ monitoring of strong-field ionization(SFI)dynamics.The method relies on coherent scattering of a probe pulse from a transient plasma grating(TPG)formed by two interf...We demonstrate an all-optical technique for in situ monitoring of strong-field ionization(SFI)dynamics.The method relies on coherent scattering of a probe pulse from a transient plasma grating(TPG)formed by two interfering femtosecond pulses in a gas target.The diffracted signal provides a real-time,relative measure of the ionization yield.We demonstrate the method’s sensitivity by resolving the attosecond-scale coherent control of the ionization rate.Unlike conventional diagnostics that directly measure charged particles,our ensemble-based optical method is non-invasive and particularly suited for non-vacuum environments.To demonstrate its utility,we apply the technique to investigate the relationship between ionization and terahertz(THz)generation in a two-color(ω+2ω)field.We measure a phase offset of(0.18±0.05)π between the maxima of the ionization yield and the THz emission.This result provides a quantitative benchmark for theoretical models and establishes the TPG technique as a practical tool for probing SFI dynamics in ensemble systems.展开更多
This study examines the influence of magnetic field and temperature on the transient voltage of a polycrystalline silicon radial junction solar cell in a dynamic regime under multispectral illumination. Radial junctio...This study examines the influence of magnetic field and temperature on the transient voltage of a polycrystalline silicon radial junction solar cell in a dynamic regime under multispectral illumination. Radial junction solar cells represent a major advancement in photovoltaic technologies, as they optimize light absorption and charge collection efficiency. The focus is on the impact of the magnetic field and temperature on the decay of transient voltage, which provides crucial information on recombination processes and the lifetime of minority carriers. The results reveal that the magnetic field tends to increase the transient voltage by directly affecting the transient electron density. Indeed, for B > 7 × 10−5 T, the magnetic field prolongs the relaxation time by increasing the transient voltage amplitude. Additionally, rising temperatures accelerate (ranging from 290 K to 450 K) recombination processes, thereby reducing the transient voltage, although this effect is moderated by the presence of a magnetic field. The study highlights the complex interaction between magnetic field and temperature, with significant impacts on the transient behaviour.展开更多
A nickel-catalyzed C(sp^(2))–H alkynylation of unprotected α-substituted benzylamines is achieved by utilizing a transient directing group. The combination of a TDG with a nickel catalyst significantly improves the ...A nickel-catalyzed C(sp^(2))–H alkynylation of unprotected α-substituted benzylamines is achieved by utilizing a transient directing group. The combination of a TDG with a nickel catalyst significantly improves the reaction step and atom economy. It has been investigated that the 2,4,6-trimethylpyridine ligand was critical to achieve the optimized reactivity. This protocol provides a straightforward route for synthesizing the alkynylated free benzylamines, featuring good substrate compatibility and monoselectivity.展开更多
Unstable operating conditions such as surge could cause damage to both aerodynamic performance and structural integrity of a compression system.This paper addresses the critical issue of aerodynamic instability in com...Unstable operating conditions such as surge could cause damage to both aerodynamic performance and structural integrity of a compression system.This paper addresses the critical issue of aerodynamic instability in compressor design,particularly focusing on an axial-centrifugal combined compressor,a widely used yet underexplored configuration.An experimental investigation was conducted on a three-stage axial and one-stage centrifugal compressor(3A1C),using two pipe systems and employing fast-responding transducers to capture the dynamic instability process from choke condition to deep surge.Results reveal that at the design speed,3A1C enters deep surge directly,whereas at off-design speeds,it experiences rotating stall and mild surge across a wide mass flow range.Some special instability features in the combined compressor can be found in the steady state map and dynamic process.The characteristic curve of the first axial stage keeps a positive slope during the whole mass flow range at an off-design speed.The first stage could work stably on the stall characteristic curve because the centrifugal stage has stronger pressurization and plays a dominant role in global aerodynamic instability.Besides,rotating instability occurs at the first rotor tip and disappears as the back pressure increases,which is also rarely seen in a single-axial compressor.This is also related to the strong pressurization of the centrifugal stage.The findings of this paper will contribute to the understanding of aerodynamic instabilities in combined compressors.展开更多
A pre-swirl system with a multi-chamber structure is crucial to the secondary air system of an aero engine.The airflow within the pre-swirl system(characterized by high-speed rotation and compressible flow)is complica...A pre-swirl system with a multi-chamber structure is crucial to the secondary air system of an aero engine.The airflow within the pre-swirl system(characterized by high-speed rotation and compressible flow)is complicated.During transient processes in aero engine operation,the pre-swirl system is subjected to upstream fluctuations,which is a less studied aspect.This paper delves into the unsteady flow characteristics within the pre-swirl system.We investigate the influence of different pressure-fluctuation boundary conditions,corresponding to step function,ramp function,and sine function,on the transient response characteristics of the pre-swirl system.The results indicate that the response characteristics are strongly affected by the upstream boundary conditions.An obvious overshoot phenomenon is observed in the actual temperature drop under the step and ramp function conditions.The peak time of the step function is 75%shorter compared to the ramp function.Furthermore,the flow parameters exhibit nonlinear growth during the transient process,emphasizing the need for consideration in future quasi-steady simulations.For the sine function condition,the pressure-fluctuation frequency minimally affects stable values of mass flow rate and actual temperature drop but exerts a substantial influence on the maximum deviation of actual temperature drop of the system.As the frequency increases from 100 Hz to 200 Hz,the maximum deviations for actual temperature drop change from around±13 K to±10 K.展开更多
Panax Ginseng(2n=48)represents a quintessential resource in traditional Chinese medicine,renowned for its outstanding medicinal and economic benefits(Choi,2008).But the late start in analyzing the ginseng genome and t...Panax Ginseng(2n=48)represents a quintessential resource in traditional Chinese medicine,renowned for its outstanding medicinal and economic benefits(Choi,2008).But the late start in analyzing the ginseng genome and the poorly developed genetic transformation system still impede the study of ginseng gene function and the application of molecular breeding.Transient transformation has the advantages of high efficiency,low cost,and short cycle while laying the foundation for stable genetic transformation(Chen et al.,2021).In the plant transformation process,the cell wall prevents exogenous DNA or protein entry,significantly reducing the efficiency of the transformation.Protoplasts,as exposed cells wrapped by the plasma membrane,are more likely to absorb exogenous DNA,RNA,and protein.Transgenic systems of protoplasts have been established in several species and applied in many fields,such as gene function research(Gou et al.,2020),gene editing(Yang et al.,2023),and physiological or molecular mechanism research(Aoyagi,2011).For instance,Oryza sativa protoplasts were employed to screen genes involved in rice defense signaling pathways through fluorescent reporter systems,with BiFC employed to verified inter-protein interactions(He et al.,2016).A study transformed Cannabis sativa L.protoplasts with the plasmids carrying GFP and RFP genes,evaluated the efficiency under different transformation conditions by flow cytometry,and verified the induction of synthetic DR5 promoter by IAA based on the constructed system(Beard et al.,2021).展开更多
Pepper(Capsicum annuum)is one of the most important horticultural crops worldwide,which makes the development of an effective protoplast system for transient gene expression highly significant.Typically,plant protopla...Pepper(Capsicum annuum)is one of the most important horticultural crops worldwide,which makes the development of an effective protoplast system for transient gene expression highly significant.Typically,plant protoplasts are initially isolated through enzymatic digestion and then used for transient transformations mediated by polyethylene glycol(PEG).However,PEG-mediated protoplast transformation suffers from low and inconsistent efficiency,is influenced by various factors,and requires greater operator expertise.Here,we present a simple and efficient protoplast system for transient gene expression in C.annuum and Nicotiana benthamiana,without PEG-mediated transfection.This procedure involved using the first and second fully expanded true leaves of pepper and N.benthamiana plants at the six-leaf stage for Agrobacterium infiltration,followed by enzymatic digestion for protoplast isolation.The resulting protoplast transfections achieved remarkably high efficiencies,facilitating functional analyses such as subcellular localization and protein—protein interaction studies(for example,BiFC,Co-IP,and Split-LUC assays).Thus,we have demonstrated a simplified and highly efficient transient expression system for protoplasts and potential wide-ranging applications in C.annuum and N.benthamiana while bypassing PEG-mediated transfection.展开更多
文摘Through adding a nonlinear self-feedback term in the evolution equations of neural network, we introduced a transiently chaotic neural network model. In order to utilize the transiently chaotic dynamics mechanism in optimization problem efficiently, we have analyzed the dynamical procedure of the transiently chaotic neural network model and studied the function of the crucial bifurcation parameter which governs the chaotic behavior of the system. Based on the dynamical analysis of the transiently chaotic neural network model, chaotic annealing algorithm is also examined and improved. As an example, we applied chaotic annealing method to the traveling salesman problem and obtained good results.
基金Funding was provided by the Citrus Research and Development Foundation(CRDF),Inc.,Lake Alfred,FL,USA.
文摘Plants have a perception system triggered by pathogen and pest signals to initiate defense.These signals include evolutionarily conserved molecules from microbes and insects termed pathogen/herbivore-associated molecular patterns(PAMPs/HAMPs).Here we showed that hexaacetyl-chitohexaose(HC),an oligosaccharide from chitin,a structural component in insect exoskeletons and fungi cell walls,upregulated defense-associated genes WRKY22,GST1,RAR1,EDS1,PAL1 and NPR2,and downregulated ICS1 at 1 h after HC treatment in Sun Chu Sha mandarin leaves.The effect was transient as defense gene transcriptional changes were not observed at 18 h after the treatment.Electrical penetration graph(EPG)recordings were used to study the feeding behavior of Asian citrus psyllid(ACP)following the HC treatment.ACP is the hemipteran vector of Candidatus Liberibacter asiaticus(CLas),the pathogen associated with huanglongbing(HLB).Adult ACP displayed reduced intercellular probing,reduced xylem feeding count and duration,and increased non-probing activity on HC-treated citrus compared to controls.During an 18-h recording,percentage for total duration of xylem ingestion,phloem ingestion,intercellular probing were lower,and the percentage of nonprobing behavior was higher in HC-treated leaves than in controls.In host-selection behavior studies,HC treatment did not alter the attractiveness of citrus leaves under light or dark conditions.In addition,ACP feeding on HC-treated leaves did not show differences in mortality for up to 10 day of exposure.In summary,we report that HC induced a transient defense in citrus and an inhibitory effect on ACP feeding but did not affect host selection or the insect fitness under the tested conditions.
基金Supported by the National Natural Science Foundation of China(No.11071238)the Key Lab of Random Complex Structures and Data Science,CAS(No.2008DP173182)the National Center for Mathematics and Interdisciplinary Sciences,CAS(No.Y029184K51)
文摘Under the condition that the damping factor is between zero and one, chaotic dynamics is proved to exist in one-dimensional transiently chaotic neural networks by Li-Misiurewicz theorem. This result extends the previous result which is done under the condition that the damping factor is zero. Because the value of damping factor affects the speed of dynamical process of transiently chaotic neural networks, this result provides more complete theoretical basis for applications. Finally, two examples by numerical simulation are given to reinforce and illustrate this result.
基金supported by the Shaanxi Sanqin Scholars Innovation Team,the Science and Technology Project of Yan’an City(No.2023-CYL-193)the Key Science Research Plan of Department of Education in Shaanxi Province(No.23JS070)the Science Research Training Project(No.CLXZ2207).
文摘Photosynthesis is a promising method for H_(2)O_(2)production,but its application in pure water is limited by slow oxidation kinetics and rapid photocarrier recombination of photocatalysts.Herein,a novel defective carbon nitride photocatalyst(D-C3-xN4)containing the C vacancies and the frustrated Lewis pairs(B and N of cyano group)is designed for H_(2)O_(2)photosynthesis,and the role of C vacancies on the electron transfer mechanism during photocatalysis is systematically investigated.The D-C_(3-x)N_(4) exhibits a H_(2)O_(2)production rate of 140.1μmol·g^(-1)·h^(-1) in pure water,which is 87.6 times that of C_(3)N_(4).Such superior performance for H_(2)O_(2)photosynthesis is found to arise from the C vacancies and frustrated Lewis pairs(FLPs).The C vacancies have strong electron-trapping ability,which greatly enhances the separation of photocarriers.The C vacancies can also effectively reduce O_(2)to*OOH via a proton-coupled process,which significantly accelerates the O_(2)reduction kinetics.Meanwhile,the FLPs show an outstanding catalytic activity for H_(2)O oxidation.This study not only provides a new structure for highly active photocatalysts,but also deepens the understanding of the electron transfer mechanism of photocatalysts with trapped sites.
基金supported by the National Natural Science Foundation of China,Nos.81870921(to YW),81974179(to ZZ),82271320(to ZZ),82071284(to YT)National Key R&D Program of China,No.2022YFA1603600(to ZZ),2019YFA0112000(to YT)+1 种基金Scientific Research and Innovation Program of Shanghai Education Commission,No.2019-01-07-00-02-E00064(to GYY)Scientific and Technological Innovation Act Program of Shanghai Science and Technology Commission,No.20JC1411900(to GYY).
文摘AAV-PHP.eB is an artificial adeno-associated virus(AAV)that crosses the blood-brain barrier and targets neurons more efficiently than other AAVs when administered systematically.While AAV-PHP.eB has been used in various disease models,its cellular tropism in cerebrovascular diseases remains unclear.In the present study,we aimed to elucidate the tropism of AAV-PHP.eB for different cell types in the brain in a mouse model of ischemic stroke and evaluate its effectiveness in mediating basic fibroblast growth factor(bFGF)gene therapy.Mice were injected intravenously with AAV-PHP.eB either 14 days prior to(pre-stroke)or 1 day following(post-stroke)transient middle cerebral artery occlusion.Notably,we observed a shift in tropism from neurons to endothelial cells with post-stroke administration of AAV-PHP.eB-mNeonGreen(mNG).This endothelial cell tropism correlated strongly with expression of the endothelial membrane receptor lymphocyte antigen 6 family member A(Ly6A).Furthermore,AAV-PHP.eB-mediated overexpression of bFGF markedly improved neurobehavioral outcomes and promoted long-term neurogenesis and angiogenesis post-ischemic stroke.Our findings underscore the significance of considering potential tropism shifts when utilizing AAV-PHP.eB-mediated gene therapy in neurological diseases and suggest a promising new strategy for bFGF gene therapy in stroke treatment.
基金supported by ANID-FONDECYT 1200908(to JF),ANID-FONDECYT 1211082 and 1250856(to GEY)by the Millennium Nucleus for the Study of Pain NCN19_038(Mi Nu SPain)(to GEY)funded by the ANID scholarship 21201176。
文摘Numerous pathological states of the nervous system involve alterations in neuronal excitability and synaptic dysfunction,which depend on the function of ion channels.Due to their critical involvement in health and disease,the search for new compounds that modulate these proteins is still relevant.Traditional medicine has long been a rich source of neuroactive compounds.For example,the indigenous Mapuche people have used the leaves and bark of the Drimys winteri tree for centuries to treat various diseases.Consequently,several studies have investigated the biological effects of compounds in Drimys winteri,highlighting sesquiterpenes such asα-humulene,drimenin,polygodial,andα-,β-,γ-eudesmol.However,there is currently no literature review focusing on the ability of these sesquiterpenes to modulate ion channels.This review summarizes the current knowledge about neuroactive compounds found in Drimys winteri,with special emphasis on their direct actions on neuronal ion channels.Several Drimys winteri sesquiterpenes modulate a diverse array of neuronal ion channels,including transient receptor potential channels,gamma-aminobutyric acid A receptors,nicotinic acetylcholine receptors,and voltage-dependent Ca^(2+)and Na^(+)channels.Interestingly,the modulation of these molecular targets by Drimys winteri sesquiterpenes correlates with their therapeutic actions.The promiscuous pharmacological profile of Drimys winteri sesquiterpenes suggests they modulate multiple protein targets in vivo,making them potentially useful for treating complex,multifactorial diseases.Further studies at the molecular level may aid in developing multitargeted drugs with enhanced therapeutic effects.
基金supported by theMajor Science and Technology Projects of China Southern Power Grid(Grant number CGYKJXM20210328).
文摘As the penetration rate of distributed energy increases,the transient power angle stability problem of the virtual synchronous generator(VSG)has gradually become prominent.In view of the situation that the grid impedance ratio(R/X)is high and affects the transient power angle stability of VSG,this paper proposes a VSG transient power angle stability control strategy based on the combination of frequency difference feedback and virtual impedance.To improve the transient power angle stability of the VSG,a virtual impedance is adopted in the voltage loop to adjust the impedance ratio R/X;and the PI control feedback of the VSG frequency difference is introduced in the reactive powervoltage link of theVSGto enhance the damping effect.Thesecond-orderVSGdynamic nonlinearmodel considering the reactive power-voltage loop is established and the influence of different proportional integral(PI)control parameters on the system balance stability is analyzed.Moreover,the impact of the impedance ratio R/X on the transient power angle stability is presented using the equal area criterion.In the simulations,during the voltage dips with the reduction of R/X from 1.6 to 0.8,Δδ_(1)is reduced from 0.194 rad to 0.072 rad,Δf_(1)is reduced from 0.170 to 0.093 Hz,which shows better transient power angle stability.Simulation results verify that compared with traditional VSG,the proposedmethod can effectively improve the transient power angle stability of the system.
基金National Natural Science Foundation of China(grant numbers 42293351,41877239,51422904 and 51379112).
文摘Advanced geological prediction is a crucial means to ensure safety and efficiency in tunnel construction.However,diff erent advanced geological forecasting methods have their own limitations,resulting in poor detection accuracy.Using multiple methods to carry out a comprehensive evaluation can eff ectively improve the accuracy of advanced geological prediction results.In this study,geological information is combined with the detection results of geophysical methods,including transient electromagnetic,induced polarization,and tunnel seismic prediction,to establish a comprehensive analysis method of adverse geology.First,the possible main adverse geological problems are determined according to the geological information.Subsequently,various physical parameters of the rock mass in front of the tunnel face can then be derived on the basis of multisource geophysical data.Finally,based on the analysis results of geological information,the multisource data fusion algorithm is used to determine the type,location,and scale of adverse geology.The advanced geological prediction results that can provide eff ective guidance for tunnel construction can then be obtained.
文摘Photocatalytic hydrogen production technology is an ideal approach to addressing energy and environmental issues,with efficient charge transfer being the key to achieving high-performance hydrogen production.Ultra-thin CuInS_(2)nanosheets were prepared through a solvothermal method.Subsequently,metallic Ni was surface-modified onto CuInS_(2)through photo-deposition to serve as a co-catalyst.The optimized photocatalyst exhibited a hydrogen production rate of 15.5 mmol·g^(-1)·h^(-1)in water when used an ascorbic acid as hole scavenger,which is 9 times that of the original CuInS_(2).Transient absorption spectra(TAS)analysis demonstrates that the hole transfer from CuInS_(2)nanosheets to ascorbic acid,yielding a long-lived electron with a lifetime of 45.6μs.The electrons in CuInS_(2)are efficiently captured by Ni as active sites for driving hydrogen evolution.In situ TAS further indicates that ascorbic acid and Ni sites synergistically promote the electron transfer dynamics of CuInS_(2),achieving an electron transfer efficiency of 48.4%.This work provides a viable strategy for designing highly efficient photocatalysts with enhanced charge transfer.
基金financially supported by the National Key Re-search and Development Program of China(Nos.2022YFB3803600 and 2022YFE0115900)the National Natural Science Foundation of China(Nos.U24A2071,22278324,22238009,22361142704,22202187,and U23A20102)+1 种基金the National Science Foundation of Hubei Province of China(No.2022CFA001)Key R&D Program Projects in Hubei Province(No.2023BAB113).
文摘S-scheme heterojunctions have gained widespread application in photocatalytic reactions due to their dis-tinctive carrier transport mechanism and remarkable redox capabilities.However,a significant challenge persists in extending carrier lifetimes while simultaneously enhancing light absorption,both of which are essential for optimizing photocatalytic activity.Herein,we report the solvothermal synthesis of ul-trathin CdS nanosheets grown in situ on two-dimensional(2D)Ni-MOF to construct 2D/2D S-scheme heterojunctions.Comprehensive characterizations reveal that the incorporation of Ni-MOF(metal-organic framework)with ligand-to-metal charge transfer(LMCT)states not only broadens optical absorption but also significantly prolongs carrier lifetimes.This synergistic enhancement,coupled with the S-scheme charge transport mechanism,enables the composite to function as a bifunctional catalyst for photocat-alytic hydrogen production and simultaneous benzylamine coupling.The optimal system demonstrates an impressive hydrogen evolution rate of 8.5 mmol g^(-1) h^(-1) and an N-benzylidenebenzylamine yield of 4.6 mmol g^(-1) h^(-1) without requiring a cocatalyst.This work underscores the potential of integrating MOFs with LMCT states into S-scheme heterojunctions to enhance interfacial charge transfer,offering valuable insights for the design of S-scheme heterojunctions for artificial photosynthesis and related fields.
基金National Natural Science Foundation of China:Study on the Molecular Mechanism of the Regulation of Crypt Goblet Cell Pyroptosis and Exocytosis to Repair Ulcerative Colitis Mucus Barrier by the Method of Clearing and Opening the Xuanfu from the Perspective of"Xuanfu-Crypt"(No.82305143),and National Natural Science Foundation of China:Exploring the Molecular Mechanism of"Hewei Jiangni Fang"Intervention in Non-erosive Reflux Disease Esophageal Hypersensitivity from the Perspective of Mas-related Gene X2/Stromal Interaction Molecule 1/Cell Adhesion Molecule 1 Pathway Regulation of Mast Cell/Dorsal Root Ganglion Communication based on the"Xinkai-Kujiang"Method(No.82374401)。
文摘OBJECTIVE:To explore if Hewei Jiangni granule(和胃降逆颗粒,HWJNG)could regulate esophageal hypersensitivity via stromal interaction molecule 1(STIM1)/transient receptor potential vanilloid subfamily member 1(TRPV1)pathway.METHODS:Qualitative analysis of HWJNG was analysis by high performance of liquid and gas chromatography.In vivo,animal model of non-erosive reflux disease(NERD)was established by fructose intake and restraint stress.HWJNG and Omeprazole were administered by gavage to the drug intervention group.Reflux and visceral hypersensitivity were analyzed by pathological changes,PH value test,mechanical paw withdrawal threshold,thermal withdrawal latency and mast cells(MCs)degranulation.In vitro,substance P(SP)-induced P815 cells and dorsal root ganglion(DRG)cells were cocultured.Expression in both mice and cells of STIM1,TRPV1,and esophageal visceral hypersensitivity-related gastrointestinal neurochemicals were validated by enzyme linked immunosorbent assays,quantitative realtime polymerase chain reaction(qRT-PCR)and Western blot.Moreover,overexpression and small interfering RNA against STIM1 were utilized to verify of the role of HWJNG in DRG cells.RESULTS:HWJNG significantly suppressed intercellular space widening,injury of mitochondrial,MCs degranulation,mechanical allodynia and heat neuropathic sensory and increased pH value of esophageal mucosa in NERD mice.HWJNG inhibited expression of visceral hypersensitivityrelated gastrointestinal neurochemicals in esophageal mucosa and activated P815 cells,and expression of the STIM1,TRPV1 and related neurotransmitters in DRG and DRG cells.STIM1 siRNA and HWJNG both reduced P815 cells adhesion to DRGs cells and Ca2+flow into the cytoplasmic space of DRG cells.Furthermore,HWJNG could reversed STIM1 overexpression induced upregulation of TRPV1.CONCLUSION:HWJNG suppressed intercellular space widening in NERD mice,stabilized MCs and restored neuronal hyperexcitability by regulating visceral hypersensitivity via STIM1/TRPV1 pathway.
文摘This study discusses the benefits and challenges of well monitoring for Gulong shale oil production.It examines the Unified Transient Analysis(UTA)method,which integrates rate and pressure data to monitor changes in fracture surface area and production efficiency in real-time.The UTA method allows for early detection of production impairments and provides feedback to optimize drawdown pressure,enhancing production without damaging fracture conductivity.Analysis of production data from Well A in the Daqing Oilfield demonstrates the method's efficacy,particularly in managing choke size adjustments and identifying fracture conductivity degradation.Despite its benefits,challenges such as data quality,manual data analysis,and the need for automated choke management are highlighted.The study underscores the necessity of integrating intelligent monitoring technologies and automating workflows to optimize Gulong shale oil production.
基金supported by Biological Breeding of Early Maturing and Disease Resistant Cotton Varieties (NO.2023ZD04041)the Project of China Agriculture Research System (Grant No. CARS-15-06)+2 种基金Natural Science Foundation of Henan Province (Grant No. 232300421041 and 222300420382)National Natural Science Foundation of China (Grant No. U21 A20213)the Central Public-interest Scientific Institution Basal Research Fund (Grant No. 1610162023017 and 1610162023028)。
文摘Background Cotton is an important crop providing the most natural fibers all over the world. The cotton genomics community has utilized whole genome sequencing data to construct an elite gene pool in which functional genes are related to agronomic traits. However, the functional validation of these genes is hindered by time-consuming and inefficient genetic transformation methods. Thus, establishing a transient transformation system of high efficiency is necessary for cotton genomics.Results To improve the efficiency of transient transformation, we used the protoplasts isolated from the etiolated cotyledon as recipient. The enzymatic digestion buffer comprised 1.5%(w/v) cellulase, 0.75%(w/v) macerozyme, and 1% hemicellulase, osmotically buffered with 0.4 mol·L^(-1) mannitol. After 5 h of dark incubation at 25℃, uniform cotton protoplasts were successfully isolated with a yield of 4.6 × 10^(6) protoplasts per gram(fresh weight) and 95% viability. We incubated 100 μL protoplasts(2.5 × 10^(5)·m L^(-1)) with 15 μg plasmid in the solution of 0.4 mol·L^(-1) mannitol and 40% PEG 4000 for 15 min, ultimately achieving an optimal transient transfection efficiency of 71.47%.Conclusions This transient system demonstrated effective utility in cellular biology research through successful applications in subcellular localization analyses, bimolecular fluorescence complementation(Bi FC) verification, and prime editing vector validation. Through systematic optimization, we established an efficient and expedited protoplast-based transient transformation system and successfully applied this platform to cotton functional genomics studies.
基金supported by the NUDT Science Foundation for Indigenous Innovation(Grant No.24-ZZCX-ZXGC-15)the National Natural Science Foundation of China(Grant Nos.12234020,12450403,and 12374263)。
文摘We demonstrate an all-optical technique for in situ monitoring of strong-field ionization(SFI)dynamics.The method relies on coherent scattering of a probe pulse from a transient plasma grating(TPG)formed by two interfering femtosecond pulses in a gas target.The diffracted signal provides a real-time,relative measure of the ionization yield.We demonstrate the method’s sensitivity by resolving the attosecond-scale coherent control of the ionization rate.Unlike conventional diagnostics that directly measure charged particles,our ensemble-based optical method is non-invasive and particularly suited for non-vacuum environments.To demonstrate its utility,we apply the technique to investigate the relationship between ionization and terahertz(THz)generation in a two-color(ω+2ω)field.We measure a phase offset of(0.18±0.05)π between the maxima of the ionization yield and the THz emission.This result provides a quantitative benchmark for theoretical models and establishes the TPG technique as a practical tool for probing SFI dynamics in ensemble systems.
文摘This study examines the influence of magnetic field and temperature on the transient voltage of a polycrystalline silicon radial junction solar cell in a dynamic regime under multispectral illumination. Radial junction solar cells represent a major advancement in photovoltaic technologies, as they optimize light absorption and charge collection efficiency. The focus is on the impact of the magnetic field and temperature on the decay of transient voltage, which provides crucial information on recombination processes and the lifetime of minority carriers. The results reveal that the magnetic field tends to increase the transient voltage by directly affecting the transient electron density. Indeed, for B > 7 × 10−5 T, the magnetic field prolongs the relaxation time by increasing the transient voltage amplitude. Additionally, rising temperatures accelerate (ranging from 290 K to 450 K) recombination processes, thereby reducing the transient voltage, although this effect is moderated by the presence of a magnetic field. The study highlights the complex interaction between magnetic field and temperature, with significant impacts on the transient behaviour.
基金supported financially by the Excellent Going Abroad Expert's Training Program in Hebei Province (No. 201940)the Hebei Natural Science Foundation of China (No. H2020208030)the S & T Program of Hebei (No. 22567607H) for financial support。
文摘A nickel-catalyzed C(sp^(2))–H alkynylation of unprotected α-substituted benzylamines is achieved by utilizing a transient directing group. The combination of a TDG with a nickel catalyst significantly improves the reaction step and atom economy. It has been investigated that the 2,4,6-trimethylpyridine ligand was critical to achieve the optimized reactivity. This protocol provides a straightforward route for synthesizing the alkynylated free benzylamines, featuring good substrate compatibility and monoselectivity.
基金supported by the National Science and Technology Major Project of China(Nos.2017-II-0004-0016 and J2019-I-0011-0011).
文摘Unstable operating conditions such as surge could cause damage to both aerodynamic performance and structural integrity of a compression system.This paper addresses the critical issue of aerodynamic instability in compressor design,particularly focusing on an axial-centrifugal combined compressor,a widely used yet underexplored configuration.An experimental investigation was conducted on a three-stage axial and one-stage centrifugal compressor(3A1C),using two pipe systems and employing fast-responding transducers to capture the dynamic instability process from choke condition to deep surge.Results reveal that at the design speed,3A1C enters deep surge directly,whereas at off-design speeds,it experiences rotating stall and mild surge across a wide mass flow range.Some special instability features in the combined compressor can be found in the steady state map and dynamic process.The characteristic curve of the first axial stage keeps a positive slope during the whole mass flow range at an off-design speed.The first stage could work stably on the stall characteristic curve because the centrifugal stage has stronger pressurization and plays a dominant role in global aerodynamic instability.Besides,rotating instability occurs at the first rotor tip and disappears as the back pressure increases,which is also rarely seen in a single-axial compressor.This is also related to the strong pressurization of the centrifugal stage.The findings of this paper will contribute to the understanding of aerodynamic instabilities in combined compressors.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDC0160000)the National Natural Science Foundation of China(No.52122603)+4 种基金the Excellence Research Group Program(No.52488101)the Shandong Provincial Natural Science Foundation of China(No.ZR2024JQ011)the Project of National Key Laboratory of Science and Technology on Advanced Light-duty Gas-turbine(No.2023-JJ-Y04)the National Science and Technology Major Project of China(No.J2019-III-0003-0046)the Taishan Scholars Program of China.
文摘A pre-swirl system with a multi-chamber structure is crucial to the secondary air system of an aero engine.The airflow within the pre-swirl system(characterized by high-speed rotation and compressible flow)is complicated.During transient processes in aero engine operation,the pre-swirl system is subjected to upstream fluctuations,which is a less studied aspect.This paper delves into the unsteady flow characteristics within the pre-swirl system.We investigate the influence of different pressure-fluctuation boundary conditions,corresponding to step function,ramp function,and sine function,on the transient response characteristics of the pre-swirl system.The results indicate that the response characteristics are strongly affected by the upstream boundary conditions.An obvious overshoot phenomenon is observed in the actual temperature drop under the step and ramp function conditions.The peak time of the step function is 75%shorter compared to the ramp function.Furthermore,the flow parameters exhibit nonlinear growth during the transient process,emphasizing the need for consideration in future quasi-steady simulations.For the sine function condition,the pressure-fluctuation frequency minimally affects stable values of mass flow rate and actual temperature drop but exerts a substantial influence on the maximum deviation of actual temperature drop of the system.As the frequency increases from 100 Hz to 200 Hz,the maximum deviations for actual temperature drop change from around±13 K to±10 K.
基金supported by the Genetic analysis of important quality and traits of ginseng and basic research on molecular design breeding(Grant No.U21A20405)。
文摘Panax Ginseng(2n=48)represents a quintessential resource in traditional Chinese medicine,renowned for its outstanding medicinal and economic benefits(Choi,2008).But the late start in analyzing the ginseng genome and the poorly developed genetic transformation system still impede the study of ginseng gene function and the application of molecular breeding.Transient transformation has the advantages of high efficiency,low cost,and short cycle while laying the foundation for stable genetic transformation(Chen et al.,2021).In the plant transformation process,the cell wall prevents exogenous DNA or protein entry,significantly reducing the efficiency of the transformation.Protoplasts,as exposed cells wrapped by the plasma membrane,are more likely to absorb exogenous DNA,RNA,and protein.Transgenic systems of protoplasts have been established in several species and applied in many fields,such as gene function research(Gou et al.,2020),gene editing(Yang et al.,2023),and physiological or molecular mechanism research(Aoyagi,2011).For instance,Oryza sativa protoplasts were employed to screen genes involved in rice defense signaling pathways through fluorescent reporter systems,with BiFC employed to verified inter-protein interactions(He et al.,2016).A study transformed Cannabis sativa L.protoplasts with the plasmids carrying GFP and RFP genes,evaluated the efficiency under different transformation conditions by flow cytometry,and verified the induction of synthetic DR5 promoter by IAA based on the constructed system(Beard et al.,2021).
基金supported by the National Natural Science Foundation of China(Grant Nos.32472536 and 32302526)the Natural Science Foundation of Anhui Province,China(Grant No.2208085MC64)+2 种基金the Outstanding Innovative Research Team for Molecular Enzymology and Detection in Anhui Provincial Universities(Grant No.2022AH010012)the University Synergy Innovation Program of Anhui Province(Grant No.GXXT-2022-067)the University Natural Science Research Program of Anhui Provincial Education Department(Grant No.KJ2021A0118).
文摘Pepper(Capsicum annuum)is one of the most important horticultural crops worldwide,which makes the development of an effective protoplast system for transient gene expression highly significant.Typically,plant protoplasts are initially isolated through enzymatic digestion and then used for transient transformations mediated by polyethylene glycol(PEG).However,PEG-mediated protoplast transformation suffers from low and inconsistent efficiency,is influenced by various factors,and requires greater operator expertise.Here,we present a simple and efficient protoplast system for transient gene expression in C.annuum and Nicotiana benthamiana,without PEG-mediated transfection.This procedure involved using the first and second fully expanded true leaves of pepper and N.benthamiana plants at the six-leaf stage for Agrobacterium infiltration,followed by enzymatic digestion for protoplast isolation.The resulting protoplast transfections achieved remarkably high efficiencies,facilitating functional analyses such as subcellular localization and protein—protein interaction studies(for example,BiFC,Co-IP,and Split-LUC assays).Thus,we have demonstrated a simplified and highly efficient transient expression system for protoplasts and potential wide-ranging applications in C.annuum and N.benthamiana while bypassing PEG-mediated transfection.
