We propose a fundamental theorem for eco-environmental surface modelling(FTEEM) in order to apply it into the fields of ecology and environmental science more easily after the fundamental theorem for Earth’s surface ...We propose a fundamental theorem for eco-environmental surface modelling(FTEEM) in order to apply it into the fields of ecology and environmental science more easily after the fundamental theorem for Earth’s surface system modeling(FTESM). The Beijing-Tianjin-Hebei(BTH) region is taken as a case area to conduct empirical studies of algorithms for spatial upscaling, spatial downscaling, spatial interpolation, data fusion and model-data assimilation, which are based on high accuracy surface modelling(HASM), corresponding with corollaries of FTEEM. The case studies demonstrate how eco-environmental surface modelling is substantially improved when both extrinsic and intrinsic information are used along with an appropriate method of HASM. Compared with classic algorithms, the HASM-based algorithm for spatial upscaling reduced the root-meansquare error of the BTH elevation surface by 9 m. The HASM-based algorithm for spatial downscaling reduced the relative error of future scenarios of annual mean temperature by 16%. The HASM-based algorithm for spatial interpolation reduced the relative error of change trend of annual mean precipitation by 0.2%. The HASM-based algorithm for data fusion reduced the relative error of change trend of annual mean temperature by 70%. The HASM-based algorithm for model-data assimilation reduced the relative error of carbon stocks by 40%. We propose five theoretical challenges and three application problems of HASM that need to be addressed to improve FTEEM.展开更多
Pesticide residue analysis plays an important role in the quality control of Chinese materia medica.This paper reports the development and validation of an analytical method for the quantitative determination of the r...Pesticide residue analysis plays an important role in the quality control of Chinese materia medica.This paper reports the development and validation of an analytical method for the quantitative determination of the residues of 39 pesticides in 12 different matrices of Chinese materia medica.Sample preparation utilized the QuEChERS method with acetonitrile:1% aqueous acetic acid(9:1,v/v)as extraction solvent followed by sample clean-up by dispersive solid phase extraction using primary secondary amine sorbent and graphitized carbon black.Extracts were then analysed by gas chromatography coupled with electron impact mass spectrometry in the selected ion monitoring mode.Limit of detection(LOD)and limit of quantitation(LOQ)values were in the ranges 0.5-50 ng/g and 1-100 ng/g,respectively.The recoveries of the 39 pesticides were in the range 75-112% with precision(as relative standard deviation,RSD)<15%.The results show that the modified QuEChERS method allows rapid and sensitive analysis of multiple pesticide residues in Chinese materia medica.展开更多
With the rapid development of the smart grid and increasingly integrated communication networks,power grids are facing serious cyber-security problems.This paper reviews existing studies on the impact of false data in...With the rapid development of the smart grid and increasingly integrated communication networks,power grids are facing serious cyber-security problems.This paper reviews existing studies on the impact of false data injection attacks on power systems from three aspects.First,false data injection can adversely affect economic dispatch by increasing the operational cost of the power system or causing sequential overloads and even outages.Second,attackers can inject false data to the power system state estimator,and this will prevent the operators from obtaining the true operating conditions of the system.Third,false data injection attacks can degrade the distributed control of distributed generators or microgrids inducing a power imbalance between supply and demand.This paper fully covers the potential vulnerabilities of power systems to cyber-attacks to help system operators understand the system vulnerability and take effective countermeasures.展开更多
Cross-kingdom herbal mi RNA was first reported in 2012.Using a modified herbal extraction protocol,we obtained 73,677,287sequences by RNA-seq from 245 traditional Chinese Medicine(TCM),of which 20,758,257 were unique ...Cross-kingdom herbal mi RNA was first reported in 2012.Using a modified herbal extraction protocol,we obtained 73,677,287sequences by RNA-seq from 245 traditional Chinese Medicine(TCM),of which 20,758,257 were unique sequences.We constructed a Bencao(herbal)small RNA(s RNA)Atlas(http://bencao.bmicc.cn),annotated the sequences by sequence-based clustering,and created a nomenclature system for Bencao s RNAs.The profiles of 21,757 mi RNAs in the Atlas were highly consistent with those of plant mi RNAs in mi RBase.Using software tools,our results demonstrated that all human genes might be regulated by s RNAs from the Bencao s RNA Atlas,part of the predicted human target genes were experimentally validated,suggesting that Bencao s RNAs might be one of the main bioactive components of herbal medicines.We established roadmaps for oligonucleotide drugs development and optimization of TCM prescriptions.Moreover,the decoctosome,a lipo-nano particle consisting of 0.5%–2.5%of the decoction,demonstrated potent medical effects.We propose a Bencao(herbal)Index,including small-molecule compounds(SM),protein peptides(P),nucleic acid(N),non-nucleic and non-proteinogenic large-molecule compounds(LM)and elements from Mendeleev's periodic table(E),to quantitatively measure the medical effects of botanic medicine.The Bencao s RNA Atlas is a resource for developing gene-targeting oligonucleotide drugs and optimizing botanical medicine,and may provide potential remedies for the theory and practice of one medicine.展开更多
Objective: To isolate high-purity gentiopicroside from the Chinese herbal Gentiana officinalis and investigate its anti-inflammatory activity against iNOS and COX-2 targets.Methods: The purity and structures of gentio...Objective: To isolate high-purity gentiopicroside from the Chinese herbal Gentiana officinalis and investigate its anti-inflammatory activity against iNOS and COX-2 targets.Methods: The purity and structures of gentiopicroside were determined by HPLC, IR, NMR, and MS. The anti-inflammatory effects of gentiopicroside were investigated by in vivo, in vitro, and molecular experiments.Results: In vitro experiment results showed that gentiopicroside inhibited nitric oxide(NO), prostaglandin E2(PGE2), and interleukin-6(IL-6) production in mouse macrophages RAW 264.7 stimulated by lipopolysaccharide. In vivo experiment found that xylene-induced mouse ear swelling was inhibited by gentiopicroside with an inhibition rate of 34.17%. Molecular docking of cyclooxygenase-2(COX-2) and inducible nitric oxide synthase(i NOS) with gentiopicroside showed that hydrogen bonds(H-bonds) were formed between the sugar fragments in gentiopicroside structure with Tyr355, Ser353, Leu352, Ser530,Arg120, and His90 of COX-2, and Glu377, Asp382, Tyr373, Tyr347, Gln263, Asn370, and Gly371 of i NOS.Thus, gentiopicroside had a lower docking score and displayed satisfactory anti-inflammatory activities.Conclusion: These results suggested that the mechanism of anti-inflammatory activity of gentiopicroside was associated with the downregulation of inflammatory cytokines, such as NO, PGE2, and IL-6, and the suppression of iNOS and COX-2. Therefore, gentiopicroside is a potential and selective iNOS and COX-2 inhibitor.展开更多
Rationally developing efficient and durable bifunctional catalysts toward oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is critical for rechargeable zinc-air batteries(ZABs).Herein,a bead-like CoSe_(...Rationally developing efficient and durable bifunctional catalysts toward oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is critical for rechargeable zinc-air batteries(ZABs).Herein,a bead-like CoSe_(2)@NC@NCNFs bifunctional catalyst was designed and fabricated by confining cubic CoSe_(2)nanoparticles to three-dimensional(3D)porous MOFs-derived nitrogen-doped carbon(NC)and one-dimensional(1D)N-doped carbon nanofibers(NCNFs)through a facile encapsulate strategy.The 1D/3D continuous network structure contributes to the improvement of specific surface area and electronic conductivity,while the strong synergistic effect between CoSe_(2)sites and Co-Nx-C sites can effectively enhance electron/mass transfer and reduce the diffusion resistance.The as-constructed CoSe_(2)@NC@NCNFs catalyst exhibits high catalytic activity and stability toward ORR/OER with a high half-wave potential of 0.80 V(vs.RHE)in ORR and a low overpotential of 280 mV at 10 mA·cm^(−2)in OER.More encouragingly,the rechargeable ZABs with CoSe_(2)@NC@NCNFs cathode deliver high peak power densities(126.8 mW·cm^(−2)),large specific capacities(763.1 mA·h·g^(−1)),and robust charge-discharge cycling stability over 240 cycles.This study provides a facile strategy for designing efficient bifunctional catalysts for rechargeable energy conversion applications.展开更多
As a widely used food preservative,methyl paraben was experimentally evidenced with serious hormonelike adverse effects.Herein,a high performance thin-layer chromatography platformed bioluminescent bioautography and i...As a widely used food preservative,methyl paraben was experimentally evidenced with serious hormonelike adverse effects.Herein,a high performance thin-layer chromatography platformed bioluminescent bioautography and image analysis for the selective quantification and confirmation of methyl paraben was proposed and validated in vinegar and coconut juice.First,the detectability of the bioautography to the analyte on different layer materials was estimated,revealing that normal silica gel was the best choice.After that,the liquid of sample extract and working solution were separated to overcome the background noises due to co-extracted matrices.The separation result was then coupled to the optimized bioautography,enabling instant and straightforward screening of the targeted conpound.For accurate quantification,bioluninescent inhibition pattern caused by the analyte was processed by image analysis,giving useful sensitivity(LOD>16 mg/kg),precision(RSD<10.1%)and accuracy(spike-recovery rate 76.9%-112.2%).Finally,the suspected result was confirmed by determining its MS fingerprint,further strengthening the reliability of screening.展开更多
Efficient bifunctional catalysts for oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)are vital for rechargeable Zn-air batteries(ZABs).Herein,an oxygen-respirable sponge-like Co@C–O–Cs catalyst with ...Efficient bifunctional catalysts for oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)are vital for rechargeable Zn-air batteries(ZABs).Herein,an oxygen-respirable sponge-like Co@C–O–Cs catalyst with oxygen-rich active sites was designed and constructed for both ORR and OER by a facile carbon dot-assisted strategy.The aerophilic triphase interface of Co@C–O–Cs cathode efficiently boosts oxygen diffusion and transfer.The theoretical calculations and experimental studies revealed that the Co–C–COC active sites can redistribute the local charge density and lower the reaction energy barrier.The Co@C–O–Cs catalyst displays superior bifunctional catalytic activities with a half-wave potential of 0.82 V for ORR and an ultralow overpotential of 294 mV at 10 mA cm^(−2) for OER.Moreover,it can drive the liquid ZABs with high peak power density(106.4 mW cm^(−2)),specific capacity(720.7 mAh g^(−1)),outstanding long-term cycle stability(over 750 cycles at 10 mA cm^(−2)),and exhibits excellent feasibility in flexible all-solid-state ZABs.These findings provide new insights into the rational design of efficient bifunctional oxygen catalysts in rechargeable metal-air batteries.展开更多
Single Image Super-Resolution(SISR)technology aims to reconstruct a clear,high-resolution image with more information from an input low-resolution image that is blurry and contains less information.This technology has...Single Image Super-Resolution(SISR)technology aims to reconstruct a clear,high-resolution image with more information from an input low-resolution image that is blurry and contains less information.This technology has significant research value and is widely used in fields such as medical imaging,satellite image processing,and security surveillance.Despite significant progress in existing research,challenges remain in reconstructing clear and complex texture details,with issues such as edge blurring and artifacts still present.The visual perception effect still needs further enhancement.Therefore,this study proposes a Pyramid Separable Channel Attention Network(PSCAN)for the SISR task.Thismethod designs a convolutional backbone network composed of Pyramid Separable Channel Attention blocks to effectively extract and fuse multi-scale features.This expands the model’s receptive field,reduces resolution loss,and enhances the model’s ability to reconstruct texture details.Additionally,an innovative artifact loss function is designed to better distinguish between artifacts and real edge details,reducing artifacts in the reconstructed images.We conducted comprehensive ablation and comparative experiments on the Arabidopsis root image dataset and several public datasets.The experimental results show that the proposed PSCAN method achieves the best-known performance in both subjective visual effects and objective evaluation metrics,with improvements of 0.84 in Peak Signal-to-Noise Ratio(PSNR)and 0.017 in Structural Similarity Index(SSIM).This demonstrates that the method can effectively preserve high-frequency texture details,reduce artifacts,and have good generalization performance.展开更多
Nucleic acids are natural biopolymers of nucleotides that store, encode, transmit and express genetic information, which play central roles in diverse cellular events and diseases in living things. The analysis of nuc...Nucleic acids are natural biopolymers of nucleotides that store, encode, transmit and express genetic information, which play central roles in diverse cellular events and diseases in living things. The analysis of nucleic acids and nucleic acids-based analysis have been widely applied in biological studies, clinical diagnosis, environmental analysis, food safety and forensic analysis.During the past decades, the field of nucleic acids analysis has been rapidly advancing with many technological breakthroughs.In this review, we focus on the methods developed for analyzing nucleic acids, nucleic acids-based analysis, device for nucleic acids analysis, and applications of nucleic acids analysis. The representative strategies for the development of new nucleic acids analysis in this field are summarized, and key advantages and possible limitations are discussed. Finally, a brief perspective on existing challenges and further research development is provided.展开更多
The removal of ammonia(NH_(3))emitted from agricultural and industrial activities is of great significance to protect human health and ecological environment.Photocatalytic NH_(3)oxidation to N2under mild conditions i...The removal of ammonia(NH_(3))emitted from agricultural and industrial activities is of great significance to protect human health and ecological environment.Photocatalytic NH_(3)oxidation to N2under mild conditions is a promising strategy.However,developing visible light photocatalysts for NH_(3)oxidation is still in its infancy.Here,we fabricate N-TiO_(2)and Ag/AgCl/N-TiO_(2)photocatalysts by sol-gel and photodeposition methods,respectively.The introduction of N not only endows TiO_(2)with visible light response(absorption edge at460 nm)but also results in the formation of heterophase junction(anatase and rutile).Thus,N-TiO_(2)shows 2.0 and 1.8 times higher than those over anatase TiO_(2)and commercial TiO_(2)for NH_(3)oxidation under full spectrum irradiation.Meanwhile,surface modification of Ag can simultaneously enhance visible light absorption(generating localized surface plasmon resonance effect)and charge separation efficiency.Therefore,the photocatalytic activity of Ag/AgCl/N-TiO_(2)is further improved.Furthermore,the presence of N and Ag also enhances the selectivity of N2product owing to the change of reaction pathway.This work simultaneously regulates photocatalytic conversion efficiency and product selectivity,providing some guidance for developing highly efficient photocatalysts for NH_(3)elimination.展开更多
Field-effect transistors are essential components of modern electronics.Nowadays,the continued scaling of electronic and optoelectronic devices is bringing silicon-based technologies close to their physical limits,cau...Field-effect transistors are essential components of modern electronics.Nowadays,the continued scaling of electronic and optoelectronic devices is bringing silicon-based technologies close to their physical limits,causing issues such as short-channel effects[1].Two-dimensional(2D)semiconductors provide an attractive solution for transistors to extend Moore’s law because of their ultrathin thickness and immunity to short-channel effects[2].To fulfill the potential of 2D semiconductors,gate dielectrics need to be simultaneously engineered to build future 2D-material-based transistors.Gate insulators with high dielectric constants(j)exhibit lower equivalent oxide thickness,which can ensure efficient gate control over channels and low gate leakage[3].Therefore,tremendous efforts have been made in searching for novel high-j dielectrics.展开更多
An integrated quantum probe for magnetic field imaging is proposed,where the nitrogen–vacancy(NV)center fixed at the fiber tip is located on the periphery of flexible ring resonator.Using flexible polyimide(PI)as the...An integrated quantum probe for magnetic field imaging is proposed,where the nitrogen–vacancy(NV)center fixed at the fiber tip is located on the periphery of flexible ring resonator.Using flexible polyimide(PI)as the substrate medium,we design a circular microstrip antenna,which can achieve a bandwidth of 140 MHz at Zeeman splitting frequency of 2.87 GHz,specifically suitable for NV center experiments.Subsequently,this antenna is seamlessly fixed at a three-dimensional-printed cylindrical support,allowing the optical fiber tip to extend out of a dedicated aperture.To mitigate errors originating from processing,precise tuning within a narrow range can be achieved by adjusting the conformal amplitude.Finally,we image the microwave magnetic field around the integrated probe with high resolution,and determine the suitable area for placing the fiber tip(SAP).展开更多
Controlling collective electronic states hold great promise for development of innovative devices. Here, we experimentally detect the modification of the charge density wave(CDW) phase transition within a 1T-TaS_(2) l...Controlling collective electronic states hold great promise for development of innovative devices. Here, we experimentally detect the modification of the charge density wave(CDW) phase transition within a 1T-TaS_(2) layer in a WS_(2)/1T-TaS_(2) heterostructure using time-resolved ultrafast spectroscopy. Laser-induced charge transfer doping strongly suppresses the commensurate CDW phase, which results in a significant decrease in both the phase transition temperature(T_(c)) and phase transition stiffness. We interpret the phenomenon that photoinduced hole doping, when surpassing a critical threshold value of ~ 10^(18)cm^(-3), sharply decreases the phase transition energy barrier. Our results provide new insights into controlling the CDW phase transition, paving the way for optical-controlled novel devices based on CDW materials.展开更多
Imbalanced data classification is the task of classifying datasets where there is a significant disparity in the number of samples between different classes.This task is prevalent in practical scenarios such as indust...Imbalanced data classification is the task of classifying datasets where there is a significant disparity in the number of samples between different classes.This task is prevalent in practical scenarios such as industrial fault diagnosis,network intrusion detection,cancer detection,etc.In imbalanced classification tasks,the focus is typically on achieving high recognition accuracy for the minority class.However,due to the challenges presented by imbalanced multi-class datasets,such as the scarcity of samples in minority classes and complex inter-class relationships with overlapping boundaries,existing methods often do not perform well in multi-class imbalanced data classification tasks,particularly in terms of recognizing minority classes with high accuracy.Therefore,this paper proposes a multi-class imbalanced data classification method called CSDSResNet,which is based on a cost-sensitive dualstream residual network.Firstly,to address the issue of limited samples in the minority class within imbalanced datasets,a dual-stream residual network backbone structure is designed to enhance the model’s feature extraction capability.Next,considering the complexities arising fromimbalanced inter-class sample quantities and imbalanced inter-class overlapping boundaries in multi-class imbalanced datasets,a unique cost-sensitive loss function is devised.This loss function places more emphasis on the minority class and the challenging classes with high interclass similarity,thereby improving the model’s classification ability.Finally,the effectiveness and generalization of the proposed method,CSDSResNet,are evaluated on two datasets:‘DryBeans’and‘Electric Motor Defects’.The experimental results demonstrate that CSDSResNet achieves the best performance on imbalanced datasets,with macro_F1-score values improving by 2.9%and 1.9%on the two datasets compared to current state-of-the-art classification methods,respectively.Furthermore,it achieves the highest precision in single-class recognition tasks for the minority cl展开更多
Intestinal cancer is one of the most frequent and lethal types of cancer.Modeling intestinal cancer using organoids has emerged in the last decade.Human intestinal cancer organoids are physiologically relevant in vitr...Intestinal cancer is one of the most frequent and lethal types of cancer.Modeling intestinal cancer using organoids has emerged in the last decade.Human intestinal cancer organoids are physiologically relevant in vitro models,which provides an unprecedented opportunity for fundamental and applied research in colorectal cancer.“Human intestinal cancer organoids”is the first set of guidelines on human intestinal organoids in China,jointly drafted and agreed by the experts from the Chinese Society for Cell Biology and its branch society:the Chinese Society for Stem Cell Research.This standard specifies terms and definitions,technical requirements,test methods for human intestinal cancer organoids,which apply to the production and quality control during the process of manufacturing and testing of human intestinal cancer organoids.It was released by the Chinese Society for Cell Biology on 24 September 2022.We hope that the publication of this standard will guide institutional establishment,acceptance and execution of proper practocal protocols,and accelerate the international standardization of human intestinal cancer organoids for clinical development and therapeutic applications.展开更多
Organoids have attracted great interest for disease modelling,drug discovery and development,and tissue growth and homeostasis investigations.However,lack of standards for quality control has become a prominent obstac...Organoids have attracted great interest for disease modelling,drug discovery and development,and tissue growth and homeostasis investigations.However,lack of standards for quality control has become a prominent obstacle to limit their translation into clinic and other applications.“Human intestinal organoids”is the first guideline on human intestinal organoids in China,jointly drafted and agreed by the experts from the Chinese Society for Cell Biology and its branch society:the Chinese Society for Stem Cell Research.This standard specifies terms and definitions,technical requirements,test methods,inspection rules for human intestinal organoids,which is applicable to quality control during the process of manufacturing and testing of human intestinal organoids.It was originally released by the Chinese Society for Cell Biology on 24 September 2022.We hope that the publication of this standard will guide institutional establishment,acceptance and execution of proper practical protocols and accelerate the international standardization of human intestinal organoids for applications.展开更多
The active site engineering of electrocatalysts,as one of the most economical and technological approaches,is a promising strategy to enhance the intrinsic activity and selectivity towards electrochemical CO_(2)reduct...The active site engineering of electrocatalysts,as one of the most economical and technological approaches,is a promising strategy to enhance the intrinsic activity and selectivity towards electrochemical CO_(2)reduction reaction.Herein,an indium-based porphyrin framework(In-TCPP)with a well-defined structure,highly dispersed catalytic center,and good stability was constructed for efficient CO_(2)-to-formate conversion.In-TCPP could achieve a high Faraday efficiency for formate(90%)and a cathodic energy efficiency of 63.8%in flow cells.In situ attenuated total reflectance Fourier transform infrared spectroscopy and density functional theory calculation confirm that the crucial intermediate is*COOH species which contributes to the formation of formate.This work is expected to provide novel insights into the precise design of active sites for high-performance electrocatalysts towards electrochemical CO_(2)reduction reaction.展开更多
The pure Zn foils with different thicknesses(0.02, 0.05, 0.1, 0.2 and 0.3 mm) were selected as interlayers to improve the quality of friction stir lap welding joint of 7075-T6 Al and AZ31 B Mg dissimilar alloys. The e...The pure Zn foils with different thicknesses(0.02, 0.05, 0.1, 0.2 and 0.3 mm) were selected as interlayers to improve the quality of friction stir lap welding joint of 7075-T6 Al and AZ31 B Mg dissimilar alloys. The effects of the interlayer thickness on joint formation, microstructure and tensile strength were analyzed. The results displayed that the maximum length of the boundary between stir zone(SZ) and thermo-mechanically affected zone in lower plate was obtained by the addition of the Zn interlayer with 0.05 mm thickness. The Mg–Zn intermetallic compounds(IMCs) were discontinuously distributed in the SZ, replacing the continuous Al–Mg IMCs. The size of Mg–Zn IMCs increased with the increase in the thickness of the Zn interlayer. The maximum tensile shear strength of 276 N mm-1 was obtained by the addition of 0.05 mm Zn foil, which increased by 45.6% of that of the joint without the Zn foil addition.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 41930647, 41590844, 41421001 & 41971358)the Strategic Priority Research Program (A) of the Chinese Academy of Sciences (Grant No. XDA20030203)+1 种基金the Innovation Project of LREIS (Grant No. O88RA600YA)the Biodiversity Investigation, Observation and Assessment Program (2019–2023) of the Ministry of Ecology and Environment of China。
文摘We propose a fundamental theorem for eco-environmental surface modelling(FTEEM) in order to apply it into the fields of ecology and environmental science more easily after the fundamental theorem for Earth’s surface system modeling(FTESM). The Beijing-Tianjin-Hebei(BTH) region is taken as a case area to conduct empirical studies of algorithms for spatial upscaling, spatial downscaling, spatial interpolation, data fusion and model-data assimilation, which are based on high accuracy surface modelling(HASM), corresponding with corollaries of FTEEM. The case studies demonstrate how eco-environmental surface modelling is substantially improved when both extrinsic and intrinsic information are used along with an appropriate method of HASM. Compared with classic algorithms, the HASM-based algorithm for spatial upscaling reduced the root-meansquare error of the BTH elevation surface by 9 m. The HASM-based algorithm for spatial downscaling reduced the relative error of future scenarios of annual mean temperature by 16%. The HASM-based algorithm for spatial interpolation reduced the relative error of change trend of annual mean precipitation by 0.2%. The HASM-based algorithm for data fusion reduced the relative error of change trend of annual mean temperature by 70%. The HASM-based algorithm for model-data assimilation reduced the relative error of carbon stocks by 40%. We propose five theoretical challenges and three application problems of HASM that need to be addressed to improve FTEEM.
基金This work was supported by a project grant(No.09ZZ008)from the Scientific Research Fund of Sichuan Provincial Education Department,China.
文摘Pesticide residue analysis plays an important role in the quality control of Chinese materia medica.This paper reports the development and validation of an analytical method for the quantitative determination of the residues of 39 pesticides in 12 different matrices of Chinese materia medica.Sample preparation utilized the QuEChERS method with acetonitrile:1% aqueous acetic acid(9:1,v/v)as extraction solvent followed by sample clean-up by dispersive solid phase extraction using primary secondary amine sorbent and graphitized carbon black.Extracts were then analysed by gas chromatography coupled with electron impact mass spectrometry in the selected ion monitoring mode.Limit of detection(LOD)and limit of quantitation(LOQ)values were in the ranges 0.5-50 ng/g and 1-100 ng/g,respectively.The recoveries of the 39 pesticides were in the range 75-112% with precision(as relative standard deviation,RSD)<15%.The results show that the modified QuEChERS method allows rapid and sensitive analysis of multiple pesticide residues in Chinese materia medica.
文摘With the rapid development of the smart grid and increasingly integrated communication networks,power grids are facing serious cyber-security problems.This paper reviews existing studies on the impact of false data injection attacks on power systems from three aspects.First,false data injection can adversely affect economic dispatch by increasing the operational cost of the power system or causing sequential overloads and even outages.Second,attackers can inject false data to the power system state estimator,and this will prevent the operators from obtaining the true operating conditions of the system.Third,false data injection attacks can degrade the distributed control of distributed generators or microgrids inducing a power imbalance between supply and demand.This paper fully covers the potential vulnerabilities of power systems to cyber-attacks to help system operators understand the system vulnerability and take effective countermeasures.
基金the National Natural Science Foundation of China(81788101,32100104)the Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences(2021-I2M-1022)+1 种基金the CAMS Endowment Fund(2021-CAMS-JZ001)the Overseas Expertise Introduction Center for Discipline Innovation(“111 Center”)(BP0820029)。
文摘Cross-kingdom herbal mi RNA was first reported in 2012.Using a modified herbal extraction protocol,we obtained 73,677,287sequences by RNA-seq from 245 traditional Chinese Medicine(TCM),of which 20,758,257 were unique sequences.We constructed a Bencao(herbal)small RNA(s RNA)Atlas(http://bencao.bmicc.cn),annotated the sequences by sequence-based clustering,and created a nomenclature system for Bencao s RNAs.The profiles of 21,757 mi RNAs in the Atlas were highly consistent with those of plant mi RNAs in mi RBase.Using software tools,our results demonstrated that all human genes might be regulated by s RNAs from the Bencao s RNA Atlas,part of the predicted human target genes were experimentally validated,suggesting that Bencao s RNAs might be one of the main bioactive components of herbal medicines.We established roadmaps for oligonucleotide drugs development and optimization of TCM prescriptions.Moreover,the decoctosome,a lipo-nano particle consisting of 0.5%–2.5%of the decoction,demonstrated potent medical effects.We propose a Bencao(herbal)Index,including small-molecule compounds(SM),protein peptides(P),nucleic acid(N),non-nucleic and non-proteinogenic large-molecule compounds(LM)and elements from Mendeleev's periodic table(E),to quantitatively measure the medical effects of botanic medicine.The Bencao s RNA Atlas is a resource for developing gene-targeting oligonucleotide drugs and optimizing botanical medicine,and may provide potential remedies for the theory and practice of one medicine.
基金supported by the National Natural Science Foundation of China (No.81660577, No.21562001, and No.81560716)Natural Science Foundation of Gansu Province (1506RJZA036 and 148RJZA064)
文摘Objective: To isolate high-purity gentiopicroside from the Chinese herbal Gentiana officinalis and investigate its anti-inflammatory activity against iNOS and COX-2 targets.Methods: The purity and structures of gentiopicroside were determined by HPLC, IR, NMR, and MS. The anti-inflammatory effects of gentiopicroside were investigated by in vivo, in vitro, and molecular experiments.Results: In vitro experiment results showed that gentiopicroside inhibited nitric oxide(NO), prostaglandin E2(PGE2), and interleukin-6(IL-6) production in mouse macrophages RAW 264.7 stimulated by lipopolysaccharide. In vivo experiment found that xylene-induced mouse ear swelling was inhibited by gentiopicroside with an inhibition rate of 34.17%. Molecular docking of cyclooxygenase-2(COX-2) and inducible nitric oxide synthase(i NOS) with gentiopicroside showed that hydrogen bonds(H-bonds) were formed between the sugar fragments in gentiopicroside structure with Tyr355, Ser353, Leu352, Ser530,Arg120, and His90 of COX-2, and Glu377, Asp382, Tyr373, Tyr347, Gln263, Asn370, and Gly371 of i NOS.Thus, gentiopicroside had a lower docking score and displayed satisfactory anti-inflammatory activities.Conclusion: These results suggested that the mechanism of anti-inflammatory activity of gentiopicroside was associated with the downregulation of inflammatory cytokines, such as NO, PGE2, and IL-6, and the suppression of iNOS and COX-2. Therefore, gentiopicroside is a potential and selective iNOS and COX-2 inhibitor.
基金supported by the National Natural Science Foundation of China(Nos.52174286,22105190)Natural Science Foundation of Hunan Province in China(2023JJ10068)Innovation-Driven Project of Central South University(No.2020CX007).
文摘Rationally developing efficient and durable bifunctional catalysts toward oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is critical for rechargeable zinc-air batteries(ZABs).Herein,a bead-like CoSe_(2)@NC@NCNFs bifunctional catalyst was designed and fabricated by confining cubic CoSe_(2)nanoparticles to three-dimensional(3D)porous MOFs-derived nitrogen-doped carbon(NC)and one-dimensional(1D)N-doped carbon nanofibers(NCNFs)through a facile encapsulate strategy.The 1D/3D continuous network structure contributes to the improvement of specific surface area and electronic conductivity,while the strong synergistic effect between CoSe_(2)sites and Co-Nx-C sites can effectively enhance electron/mass transfer and reduce the diffusion resistance.The as-constructed CoSe_(2)@NC@NCNFs catalyst exhibits high catalytic activity and stability toward ORR/OER with a high half-wave potential of 0.80 V(vs.RHE)in ORR and a low overpotential of 280 mV at 10 mA·cm^(−2)in OER.More encouragingly,the rechargeable ZABs with CoSe_(2)@NC@NCNFs cathode deliver high peak power densities(126.8 mW·cm^(−2)),large specific capacities(763.1 mA·h·g^(−1)),and robust charge-discharge cycling stability over 240 cycles.This study provides a facile strategy for designing efficient bifunctional catalysts for rechargeable energy conversion applications.
基金financially supported by National Natural Science Foundation of China (21804058)Shanxi Postdoc Reward (SXBYKY2022001)+1 种基金Shanxi Scholarship Council of China (2021068)Shanxi Agricultural University High-Level Talent Project (2021XG013)。
文摘As a widely used food preservative,methyl paraben was experimentally evidenced with serious hormonelike adverse effects.Herein,a high performance thin-layer chromatography platformed bioluminescent bioautography and image analysis for the selective quantification and confirmation of methyl paraben was proposed and validated in vinegar and coconut juice.First,the detectability of the bioautography to the analyte on different layer materials was estimated,revealing that normal silica gel was the best choice.After that,the liquid of sample extract and working solution were separated to overcome the background noises due to co-extracted matrices.The separation result was then coupled to the optimized bioautography,enabling instant and straightforward screening of the targeted conpound.For accurate quantification,bioluninescent inhibition pattern caused by the analyte was processed by image analysis,giving useful sensitivity(LOD>16 mg/kg),precision(RSD<10.1%)and accuracy(spike-recovery rate 76.9%-112.2%).Finally,the suspected result was confirmed by determining its MS fingerprint,further strengthening the reliability of screening.
基金supported by the National Key Research and Development Program of China(No.2019YFC1907801)National Natural Science Foundation of China(No.52174286)+1 种基金the Science and Technology Innovation Program of Hunan Province(2021RC3014)Innovation-Driven Project of Central South University(No.2020CX007)。
文摘Efficient bifunctional catalysts for oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)are vital for rechargeable Zn-air batteries(ZABs).Herein,an oxygen-respirable sponge-like Co@C–O–Cs catalyst with oxygen-rich active sites was designed and constructed for both ORR and OER by a facile carbon dot-assisted strategy.The aerophilic triphase interface of Co@C–O–Cs cathode efficiently boosts oxygen diffusion and transfer.The theoretical calculations and experimental studies revealed that the Co–C–COC active sites can redistribute the local charge density and lower the reaction energy barrier.The Co@C–O–Cs catalyst displays superior bifunctional catalytic activities with a half-wave potential of 0.82 V for ORR and an ultralow overpotential of 294 mV at 10 mA cm^(−2) for OER.Moreover,it can drive the liquid ZABs with high peak power density(106.4 mW cm^(−2)),specific capacity(720.7 mAh g^(−1)),outstanding long-term cycle stability(over 750 cycles at 10 mA cm^(−2)),and exhibits excellent feasibility in flexible all-solid-state ZABs.These findings provide new insights into the rational design of efficient bifunctional oxygen catalysts in rechargeable metal-air batteries.
基金supported by Beijing Municipal Science and Technology Project(No.Z221100007122003).
文摘Single Image Super-Resolution(SISR)technology aims to reconstruct a clear,high-resolution image with more information from an input low-resolution image that is blurry and contains less information.This technology has significant research value and is widely used in fields such as medical imaging,satellite image processing,and security surveillance.Despite significant progress in existing research,challenges remain in reconstructing clear and complex texture details,with issues such as edge blurring and artifacts still present.The visual perception effect still needs further enhancement.Therefore,this study proposes a Pyramid Separable Channel Attention Network(PSCAN)for the SISR task.Thismethod designs a convolutional backbone network composed of Pyramid Separable Channel Attention blocks to effectively extract and fuse multi-scale features.This expands the model’s receptive field,reduces resolution loss,and enhances the model’s ability to reconstruct texture details.Additionally,an innovative artifact loss function is designed to better distinguish between artifacts and real edge details,reducing artifacts in the reconstructed images.We conducted comprehensive ablation and comparative experiments on the Arabidopsis root image dataset and several public datasets.The experimental results show that the proposed PSCAN method achieves the best-known performance in both subjective visual effects and objective evaluation metrics,with improvements of 0.84 in Peak Signal-to-Noise Ratio(PSNR)and 0.017 in Structural Similarity Index(SSIM).This demonstrates that the method can effectively preserve high-frequency texture details,reduce artifacts,and have good generalization performance.
文摘Nucleic acids are natural biopolymers of nucleotides that store, encode, transmit and express genetic information, which play central roles in diverse cellular events and diseases in living things. The analysis of nucleic acids and nucleic acids-based analysis have been widely applied in biological studies, clinical diagnosis, environmental analysis, food safety and forensic analysis.During the past decades, the field of nucleic acids analysis has been rapidly advancing with many technological breakthroughs.In this review, we focus on the methods developed for analyzing nucleic acids, nucleic acids-based analysis, device for nucleic acids analysis, and applications of nucleic acids analysis. The representative strategies for the development of new nucleic acids analysis in this field are summarized, and key advantages and possible limitations are discussed. Finally, a brief perspective on existing challenges and further research development is provided.
基金supported by the National Natural Science Foundation of China(Nos.22206045 and 22206102)the Doctoral Scientific Research Start-up Foundation from Henan University of Technology(No.2021BS059)the Science and Technology Key Project Foundation from Education Department of Henan Province(No.23A610011)。
文摘The removal of ammonia(NH_(3))emitted from agricultural and industrial activities is of great significance to protect human health and ecological environment.Photocatalytic NH_(3)oxidation to N2under mild conditions is a promising strategy.However,developing visible light photocatalysts for NH_(3)oxidation is still in its infancy.Here,we fabricate N-TiO_(2)and Ag/AgCl/N-TiO_(2)photocatalysts by sol-gel and photodeposition methods,respectively.The introduction of N not only endows TiO_(2)with visible light response(absorption edge at460 nm)but also results in the formation of heterophase junction(anatase and rutile).Thus,N-TiO_(2)shows 2.0 and 1.8 times higher than those over anatase TiO_(2)and commercial TiO_(2)for NH_(3)oxidation under full spectrum irradiation.Meanwhile,surface modification of Ag can simultaneously enhance visible light absorption(generating localized surface plasmon resonance effect)and charge separation efficiency.Therefore,the photocatalytic activity of Ag/AgCl/N-TiO_(2)is further improved.Furthermore,the presence of N and Ag also enhances the selectivity of N2product owing to the change of reaction pathway.This work simultaneously regulates photocatalytic conversion efficiency and product selectivity,providing some guidance for developing highly efficient photocatalysts for NH_(3)elimination.
文摘Field-effect transistors are essential components of modern electronics.Nowadays,the continued scaling of electronic and optoelectronic devices is bringing silicon-based technologies close to their physical limits,causing issues such as short-channel effects[1].Two-dimensional(2D)semiconductors provide an attractive solution for transistors to extend Moore’s law because of their ultrathin thickness and immunity to short-channel effects[2].To fulfill the potential of 2D semiconductors,gate dielectrics need to be simultaneously engineered to build future 2D-material-based transistors.Gate insulators with high dielectric constants(j)exhibit lower equivalent oxide thickness,which can ensure efficient gate control over channels and low gate leakage[3].Therefore,tremendous efforts have been made in searching for novel high-j dielectrics.
基金Project supported by the National Key Research and Development Program of China(Grant No.2021YFB2012600)the Science and Technology Plan Project of State Administration of Market Regulation,China(Grant No.2021MK039)。
文摘An integrated quantum probe for magnetic field imaging is proposed,where the nitrogen–vacancy(NV)center fixed at the fiber tip is located on the periphery of flexible ring resonator.Using flexible polyimide(PI)as the substrate medium,we design a circular microstrip antenna,which can achieve a bandwidth of 140 MHz at Zeeman splitting frequency of 2.87 GHz,specifically suitable for NV center experiments.Subsequently,this antenna is seamlessly fixed at a three-dimensional-printed cylindrical support,allowing the optical fiber tip to extend out of a dedicated aperture.To mitigate errors originating from processing,precise tuning within a narrow range can be achieved by adjusting the conformal amplitude.Finally,we image the microwave magnetic field around the integrated probe with high resolution,and determine the suitable area for placing the fiber tip(SAP).
基金supported by the National Key Research and Development Program of China (Grant No. 2021YFA1400201)the CAS Project for Young Scientists in Basic Research (Grant No. YSBR059)+5 种基金the Beijing Natural Science Foundation (Grant No. 4191003)the National Natural Science Foundation of China (Grant No. 11774408)the Scientific Instrument Developing Project of the Chinese Academy of Sciences (Grant No. GJJSTD20200005)the Strategic Priority Research Program of Chinese Academy of Sciences (Grant Nos. XDB36000000 and XDB30000000)the International Partnership Program of Chinese Academy of Sciences (Grant No. GJHZ1826)CAS Interdisciplinary Innovation Team。
文摘Controlling collective electronic states hold great promise for development of innovative devices. Here, we experimentally detect the modification of the charge density wave(CDW) phase transition within a 1T-TaS_(2) layer in a WS_(2)/1T-TaS_(2) heterostructure using time-resolved ultrafast spectroscopy. Laser-induced charge transfer doping strongly suppresses the commensurate CDW phase, which results in a significant decrease in both the phase transition temperature(T_(c)) and phase transition stiffness. We interpret the phenomenon that photoinduced hole doping, when surpassing a critical threshold value of ~ 10^(18)cm^(-3), sharply decreases the phase transition energy barrier. Our results provide new insights into controlling the CDW phase transition, paving the way for optical-controlled novel devices based on CDW materials.
基金supported by Beijing Municipal Science and Technology Project(No.Z221100007122003)。
文摘Imbalanced data classification is the task of classifying datasets where there is a significant disparity in the number of samples between different classes.This task is prevalent in practical scenarios such as industrial fault diagnosis,network intrusion detection,cancer detection,etc.In imbalanced classification tasks,the focus is typically on achieving high recognition accuracy for the minority class.However,due to the challenges presented by imbalanced multi-class datasets,such as the scarcity of samples in minority classes and complex inter-class relationships with overlapping boundaries,existing methods often do not perform well in multi-class imbalanced data classification tasks,particularly in terms of recognizing minority classes with high accuracy.Therefore,this paper proposes a multi-class imbalanced data classification method called CSDSResNet,which is based on a cost-sensitive dualstream residual network.Firstly,to address the issue of limited samples in the minority class within imbalanced datasets,a dual-stream residual network backbone structure is designed to enhance the model’s feature extraction capability.Next,considering the complexities arising fromimbalanced inter-class sample quantities and imbalanced inter-class overlapping boundaries in multi-class imbalanced datasets,a unique cost-sensitive loss function is devised.This loss function places more emphasis on the minority class and the challenging classes with high interclass similarity,thereby improving the model’s classification ability.Finally,the effectiveness and generalization of the proposed method,CSDSResNet,are evaluated on two datasets:‘DryBeans’and‘Electric Motor Defects’.The experimental results demonstrate that CSDSResNet achieves the best performance on imbalanced datasets,with macro_F1-score values improving by 2.9%and 1.9%on the two datasets compared to current state-of-the-art classification methods,respectively.Furthermore,it achieves the highest precision in single-class recognition tasks for the minority cl
基金supported by grants from the National Natural Science Foundation of China(31988101 to Y.-G.C.82173461 To G.Q.H.)+3 种基金Guangdong Basic and Applied Basic Research Foundation(2021A1515111215)to Y.L.W.China Postdoctoral Science Foundation(2021M703230 and 2022T150653)to Y.L.W.National Key R&D Program of China(2018YFA0108400)to T.B.Z.the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA16040501)to A.J.M..
文摘Intestinal cancer is one of the most frequent and lethal types of cancer.Modeling intestinal cancer using organoids has emerged in the last decade.Human intestinal cancer organoids are physiologically relevant in vitro models,which provides an unprecedented opportunity for fundamental and applied research in colorectal cancer.“Human intestinal cancer organoids”is the first set of guidelines on human intestinal organoids in China,jointly drafted and agreed by the experts from the Chinese Society for Cell Biology and its branch society:the Chinese Society for Stem Cell Research.This standard specifies terms and definitions,technical requirements,test methods for human intestinal cancer organoids,which apply to the production and quality control during the process of manufacturing and testing of human intestinal cancer organoids.It was released by the Chinese Society for Cell Biology on 24 September 2022.We hope that the publication of this standard will guide institutional establishment,acceptance and execution of proper practocal protocols,and accelerate the international standardization of human intestinal cancer organoids for clinical development and therapeutic applications.
基金supported by grants from the National Natural Science Foundation of China(31988101 to Y.-G.C.82173461 To G.Q.H.)+3 种基金Guangdong Basic and Applied Basic Research Foundation(2021A1515111215)to Y.L.W.China Postdoctoral Science Foundation(2021M703230 and 2022T150653)to Y.L.W.National Key R&D Program of China(2018YFA0108400)to T.B.Z.the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA16040501)to A.J.M..
文摘Organoids have attracted great interest for disease modelling,drug discovery and development,and tissue growth and homeostasis investigations.However,lack of standards for quality control has become a prominent obstacle to limit their translation into clinic and other applications.“Human intestinal organoids”is the first guideline on human intestinal organoids in China,jointly drafted and agreed by the experts from the Chinese Society for Cell Biology and its branch society:the Chinese Society for Stem Cell Research.This standard specifies terms and definitions,technical requirements,test methods,inspection rules for human intestinal organoids,which is applicable to quality control during the process of manufacturing and testing of human intestinal organoids.It was originally released by the Chinese Society for Cell Biology on 24 September 2022.We hope that the publication of this standard will guide institutional establishment,acceptance and execution of proper practical protocols and accelerate the international standardization of human intestinal organoids for applications.
基金This work was supported by the National Natural Science Foundation of China(Nos.22071172,52121002,51733004,51725304,and 21907043)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB12030300)the Ministry of Science and Technology of China(No.2018YFA0703200)。
文摘The active site engineering of electrocatalysts,as one of the most economical and technological approaches,is a promising strategy to enhance the intrinsic activity and selectivity towards electrochemical CO_(2)reduction reaction.Herein,an indium-based porphyrin framework(In-TCPP)with a well-defined structure,highly dispersed catalytic center,and good stability was constructed for efficient CO_(2)-to-formate conversion.In-TCPP could achieve a high Faraday efficiency for formate(90%)and a cathodic energy efficiency of 63.8%in flow cells.In situ attenuated total reflectance Fourier transform infrared spectroscopy and density functional theory calculation confirm that the crucial intermediate is*COOH species which contributes to the formation of formate.This work is expected to provide novel insights into the precise design of active sites for high-performance electrocatalysts towards electrochemical CO_(2)reduction reaction.
基金supported by the National Natural Science Foundation of China (No. 51874201)
文摘The pure Zn foils with different thicknesses(0.02, 0.05, 0.1, 0.2 and 0.3 mm) were selected as interlayers to improve the quality of friction stir lap welding joint of 7075-T6 Al and AZ31 B Mg dissimilar alloys. The effects of the interlayer thickness on joint formation, microstructure and tensile strength were analyzed. The results displayed that the maximum length of the boundary between stir zone(SZ) and thermo-mechanically affected zone in lower plate was obtained by the addition of the Zn interlayer with 0.05 mm thickness. The Mg–Zn intermetallic compounds(IMCs) were discontinuously distributed in the SZ, replacing the continuous Al–Mg IMCs. The size of Mg–Zn IMCs increased with the increase in the thickness of the Zn interlayer. The maximum tensile shear strength of 276 N mm-1 was obtained by the addition of 0.05 mm Zn foil, which increased by 45.6% of that of the joint without the Zn foil addition.
