Carbon-doped CuFe_(2)O_(4) with C-O-M channels for enhanced Fenton-like degradation of tetracycline hydrochloride: From construction to mechanism

Carbon-doped copper ferrite(C–CuFe_(2)O_(4))was synthesized by a simple two-step hydrothermal method,which showed enhanced tetracycline hydrochloride(TCH)removal efficiency as compared to the pure CuFe_(2)O_(4) in Fenton-like reaction.A removal efficiency of 94%was achieved with 0.2 g L^(-1) catalyst and 20 mmol L^(-1) H_(2)O_(2) within 90 min.We demonstrated that 5%C–CuFe_(2)O_(4) catalyst in the presence of H_(2)O_(2) was significantly efficient for TCH degradation under the near-neutral pH(5–9)without buffer.Multiple techniques,including SEM,TEM,XRD,FTIR,Raman,XPS M€ossbauer and so on,were conducted to investigate the structures,morphologies and electronic properties of as-prepared samples.The introduction of carbon can effectively accelerate electron transfer by cooperating with Cu and Fe to activate H_(2)O_(2) to generate·OH and·O_(2)^(-).Particularly,theoretical calculations display that the p,p,d orbital hybridization of C,O,Cu and Fe can form C–O–Cu and C–O–Fe bonds,and the electrons on carbon can transfer to metal Cu and Fe along the C–O–Fe and C–O–Cu channels,thus forming electron-rich reactive centers around Fe and Cu.This work provides lightful reference for the modification of spinel ferrites in Fenton-like application.

Seasonal changes in gut microbiota of sea cucumber over natural aestivation cycle

Sea cucumber Apostichopus japonicus is an ideal model organism for marine invertebrate aestivation;it annually enters a“sleeping state”for nearly 3 months when ambient water temperature range is 25–30℃.The natural fasting is accompanied by remodeling the intestinal biota and function,which is a part of host biology and could affect the gut microbiota.We investigatesd the impact of annual aestivation on gut microbiota using high-throughput sequencing of 16S rRNA amplicons.Results reveal a notable alteration in the composition of gut bacteria during aestivation during which various indigenous families and genera that exhibit a preference for dietary glycans(e.g.,family Rhodobacteraceae and Flavobacteriaceae)decreased,while the taxa capable of utilizing substrates derived from the host(e.g.,genus Akkermansia and Prevotella)increased,and so did certain opportunistic pathogenic bacteria.Moreover,the investigation delved into the gut morphology and immunity response of A.japonicus and reveal that the intestine of A.japonicus undergoes substantial atrophy and degeneration during aestivation.However,there was an observed augmentation in the levels of acid and neutral mucin within mucous cells,as well as an enhanced immune defense response(as evidenced by increased gene expression of AjTLR3,LITAF,Ajp105,and LYZ).These results imply that the composition of sea cucumber gut microbiota differed between aestivation and active periods,which potentially affects the intestinal functions of the host and the symbiotic relationship between host and its microbiota over the activeaestivation cycle.

Mechanistic insights into stepwise activation of malachite for enhancing surface reactivity and flotation performance

Malachite is a common copper oxide mineral that is often enriched using the sulfidization-xanthate flotation method.Currently,the direct sulfidization method cannot yield copper concentrate products.Therefore,a new sulfidization flotation process was developed to promote the efficient recovery of malachite.In this study,Cu^(2+) was used as an activator to interact with the sample surface and increase its reaction sites,thereby strengthening the mineral sulfidization process and reactivity.Compared to single copper ion activation,the flota-tion effect of malachite significantly increased after stepwise Cu^(2+) activation.Zeta potential,X-ray photoelectron spectroscopy(XPS),time-of-flight secondary ion mass spectroscopy(ToF-SIMS),scanning electron microscopy and energy dispersive spectrometry(SEM-EDS),and atomic force microscopy(AFM)analysis results indicated that the adsorption of S species was significantly enhanced on the mineral surface due to the increase in active Cu sites after Cu^(2+) stepwise activation.Meanwhile,the proportion of active Cu-S spe-cies also increased,further improving the reaction between the sample surface and subsequent collectors.Fourier-transform infrared spec-troscopy(FT-IR)and contact angle tests implied that the xanthate species were easily and stably adsorbed onto the mineral surface after Cu^(2+) stepwise activation,thereby improving the hydrophobicity of the mineral surface.Therefore,the copper sites on the malachite sur-face after Cu^(2+) stepwise activation promote the reactivity of the mineral surface and enhance sulfidization flotation of malachite.

The pathogenic mechanism of syndactyly type V identified in aHoxd13Q50R knock-in mice

Syndactyly type V (SDTY5) is an autosomal dominant extremity malformation characterized by fusion of the fourth and fifthmetacarpals. In the previous publication, we first identified a heterozygous missense mutation Q50R in homeobox domain (HD) ofHOXD13 in a large Chinese family with SDTY5. In order to substantiate the pathogenicity of the variant and elucidate the underlyingpathogenic mechanism causing limb malformation, transcription-activator-like effector nucleases (TALEN) was employed togenerate a Hoxd13Q50R mutant mouse. The mutant mice exhibited obvious limb malformations including slight brachydactyly andpartial syndactyly between digits 2-4 in the heterozygotes, and severe syndactyly, brachydactyly and polydactyly in homozygotes.Focusing on BMP2 and SHH/GREM1/AER-FGF epithelial mesenchymal (e-m) feedback, a crucial signal pathway for limbdevelopment, we found the ectopically expressed Shh, Grem1 and Fgf8 and down-regulated Bmp2 in the embryonic limb bud atE10.5 to E12.5. A transcriptome sequencing analysis was conducted on limb buds (LBs) at E11.5, revealing 31 genes that exhibitednotable disparities in mRNA level between the Hoxd13Q50R homozygotes and the wild-type. These genes are known to be involvedin various processes such as limb development, cell proliferation, migration, and apoptosis. Our findings indicate that the ectopicexpression of Shh and Fgf8, in conjunction with the down-regulation of Bmp2, results in a failure of patterning along both theanterior-posterior and proximal-distal axes, as well as a decrease in interdigital programmed cell death (PCD). This cascadeultimately leads to the development of syndactyly and brachydactyly in heterozygous mice, and severe limb malformations inhomozygous mice. These findings suggest that abnormal expression of SHH, FGF8, and BMP2 induced by HOXD13Q50R may beresponsible for the manifestation of human SDTY5.

Rosaceae phylogenomic studies provide insights into the evolution of new genes

Rosa banksiae,known as Lady Banks'rose,is a perennial ornamental crop and a versatile herb in traditional Chinese medicine.Given the lack of genomic resources,we assembled a Hi Fi and Nanopore sequencing-derived 458.58 Mb gap-free telomere-to-telomere high-quality R.banksiae genome with a scaffold N50=63.90 Mb.The genome of R.banksiae exhibited no lineage-specific whole-genome duplication compared with other Rosaceae.The phylogenomic analysis of 13 Rosaceae and Arabidopsis through a comparative genomics study showed that numerous gene families were lineage-specific both before and after the diversification of Rosaceae.Some of these genes are candidates for new genes that have evolved from parental genes through fusion events.Fusion genes are divided into three types:Type-I and Type-II genes contain two parental genes that are generated by duplication,distributed in the same and different regions of the genome,respectively;and Type-III can only be detected in one parental gene.Here,Type-I genes are found to have more relaxed selection pressure and lower Ks values than Type-II,indicating that these newly evolved Type-I genes may play important roles in driving phenotypic evolution.Functional analysis exhibited that newly formed fusion genes can regulate the phenotype traits of plant growth and development,suggesting the functional significance of these genes.This study identifies new fusion genes that could be responsible for phenotype evolution and provides information on the evolutionary history of recently diverged species in the Rosa genus.Our data represents the major progress in understanding the new fusion genes evolution pattern of Rosaceae and provides an invaluable resource for phylogenomic studies in plants.

Enhanced sulfidization flotation of cuprite by surface modification with hydrogen peroxide

Hydrogen peroxide was used as an oxidant to modify the cuprite surface and enhance its sulfidization.Surface-adsorption and infrared spectroscopy measurements indicated that the modification of the cuprite surface with hydrogen peroxide before sulfidization increased the adsorption capacity of xanthate.Zeta potential,scanning electron microscopy-energy dispersive X-ray spectroscopy,X-ray photoelectron spectroscopy,and time-of-flight secondary ion mass spectrometry results showed that the modification with hydrogen peroxide increased the contents of S^(2−)and Sn^(2−)species on the cuprite surface.Microflotation tests showed that the recovery of cuprite increased from 61.74%to 83.30%after the modification of the surface with hydrogen peroxide.These results confirm that the modification of the cuprite surface with hydrogen peroxide enhances the sulfidization of cuprite,which in turn improves its flotation.

Enhanced sulfidization of azurite surfaces by ammonium phosphate and its effect on flotation

Although azurite is one of the most important copper oxide minerals,the recovery of this mineral via sulfidization-xanthate flotation is typically unsatisfactory.The present work demonstrated the enhanced sulfidization of azurite surfaces using ammonia phosphate((NH_(4))_(3)PO_(4)) together with Na_(2)S,based on micro-flotation experiments,time-of-flight secondary ion mass spectrometry(ToF-SIMS),X-ray photoelectron spectroscopy(XPS),zeta-potential measurements,contact angle measurements,Fourier-transform infrared(FT-IR)spectroscopy,and ultraviolet-visible(UV-Vis)spectroscopy.Micro-flotation experiments showed that the floatability of azurite was increased following the simultaneous addition of(NH_(4))_(3)PO_(4)and Na_(2)S.ToF-SIMS and XPS analyses demonstrated the formation of a high content of S species on the azurite surface and an increase in the number of Cu(I)species after exposure to(NH_(4))_(3)PO_(4)and Na_(2)S,compared with the azurite-Na_(2)S system.The zeta potential of azurite particles was negatively shifted and the contact angle on the azurite surface was increased with the addition of(NH_(4))_(3)PO_(4)prior to Na_(2)S.These results indicate that treatment with(NH_(4))_(3)PO_(4) enhances the sulfidization of azurite surfaces,which in turn promotes xanthate attachment.FT-IR and UV-Vis analyses confirmed that the addition of(NH_(4))_(3)PO_(4) increased the adsorption of xanthate with reducing the consumption of xanthate during the azurite flotation process.Thus,(NH_(4))_(3)PO_(4) has a beneficial effect on the sulfidization flotation of azurite.

Adsorption behavior and mechanism of copper ions in the sulfidization flotation of malachite

Malachite is one of the main minerals used for the industrial enrichment and recovery of copper oxide resources, and copper ions are unavoidable metal ions in the flotation pulp. The microflotation, contact angle, and adsorption experiments indicated that pretreatment with an appropriate concentration of copper ions could improve the malachite recovery, and the addition of excess copper ions reduced the hydrophobicity of the malachite surface. The results of zeta potential tests indicated that sodium sulfide and butyl xanthate were also adsorbed on the surface of malachite pretreated with copper ions. X-ray photoelectron spectroscopy(XPS) results indicated that —Cu—O and —Cu—OH bonds were formed on the surface of the samples. After pretreatment with an appropriate concentration of copper ions, the number of —OH groups on the mineral surface decreased, whereas the number of Cu—S groups on the mineral surface increased, which was conducive to the sulfidization of malachite. After adding a high concentration of copper ions, the —OH groups on the mineral surface increased, whereas the number of Cu—S groups decreased, which had an adverse effect on the sulfidization flotation of malachite. Time-of-flight secondary ion mass spectrometry showed that pretreatment with copper ions resulted in a thicker sulfidization layer on the mineral surface.

Failure mechanism of bulk silicon anode electrodes for lithium-ion batteries

Silicon has been investigated extensively as a promising anode material for rechargeable lithium-ion bat- teries. Understanding the failure mechanism of silicon-based anode electrodes for lithium-ion batteries is essential to solve the problem of low coulombic efficiency and capacity fading on cycling and also to further commercialize this very new energetic material in cells. To reach this goal, the structure changes of bulk silicon particles and electrode after cycling were studied using ex-situ scanning electron microscopy （SEM） and X-ray diffraction （XRD） techniques. The SEM images indicated that the microstructural changes of the bulk silicon particles during cycling led to a layer rupture of the electrode and then the breakdown of the conductive network and the failure of the electrode. The result contributes to the basic understanding of the failure mechanism of a bulk sil- icon anode electrode for lithium-ion batteries.

Pickering interfacial biocatalysis with enhanced diffusion processes for CO_(2) mineralization

Utilization of carbon dioxide(CO_(2))has become a crucial and anticipated solution to address environmental and ecological issues.Enzymes such as carbonic anhydrase(CA)can efficiently convert CO_(2) into various platform chemicals under ambient conditions,which offers a promising way for CO_(2) utilization.Herein,we constructed a Pickering interfacial biocatalytic system(PIBS)stabilized by CA‐embedded MOFs(ZIF‐8 and ZIF‐L)for CO_(2) mineralization.Through structure engineering of MOFs and incorporation of Pickering emulsion,the internal and external diffusion processes of CO_(2) during the enzymatic mineralization were greatly intensified.When CO_(2) was ventilated at a flow rate of 50 mL min^(–1) for 1 h,the pH value of PIBS dropped from~8.00 to~6.50,while the average pH value of free system only dropped to~7.15,indicating that the initial reaction rate of CO_(2) mineralization of PIBS is nearly twice that of the free system.After the 8^(th) cycle reaction,PIBS can still produce more than 9.8 mg of CaCO_(3) in 5 min,realizing efficient and continuous mineralization of CO_(2).

套管中弯曲型Lamb波频散特征的理论和实验分析

通过建立钻井液、套管和水泥等多层介质模型,理论模拟和实验测量相结合研究弯曲型Lamb波在套后耦合不同速度水泥时的频散、衰减以及全波波形。理论模拟结果发现若测量频段弯曲型Lamb波的相速度与水泥纵波速度相交,弯曲型Lamb波的频散曲线在相交的频率点会出现速度跃变,频散曲线不再连续,且断点前后其衰减值差异大,接收到的直达弯曲型Lamb波也展现出两个紧凑的波包。实验结果也印证了频散曲线不连续的现象,实验测量波形提取的频散曲线与解析计算的频散曲线吻合。此现象为直接从频散曲线断点获取水泥的纵波速度以及区分套后耦合水泥的类型提供了可能。

Machine learning-enabled MIMO-FBMC communication channel parameter estimation in IIoT: A distributed CS approach

Compressed Sensing(CS)is a Machine Learning(ML)method,which can be regarded as a single-layer unsupervised learning method.It mainly emphasizes the sparsity of the model.In this paper,we study an ML-based CS Channel Estimation(CE)method for wireless communications,which plays an important role in Industrial Internet of Things(IIoT)applications.For the sparse correlation between channels in Multiple Input Multiple Output Filter Bank MultiCarrier with Offset Quadrature Amplitude Modulation(MIMO-FBMC/OQAM)systems,a Distributed Compressed Sensing(DCS)-based CE approach is studied.A distributed sparse adaptive weak selection threshold method is proposed for CE.Firstly,the correlation between MIMO channels is utilized to represent a joint sparse model,and CE is transformed into a joint sparse signal reconstruction problem.Then,the number of correlation atoms for inner product operation is optimized by weak selection threshold,and sparse signal reconstruction is realized by sparse adaptation.The experiment results show that the proposed DCS-based method not only estimates the multipath channel components accurately but also achieves higher CE performance than classical Orthogonal Matching Pursuit(OMP)method and other traditional DCS methods in the time-frequency dual selective channels.

Establishment of a non-lethal model of antibody-dependent enhancement of infection in A129 mice based on a non-mouse-adapted dengue virus strain

DEAR EDITOR,Dengue fever(DF),caused by dengue virus(DENV)infection,is a highly prevalent mosquito-borne infectious disease.The development of antiviral drugs and vaccines relies on the clinical utility of dengue infection models,particularly those involving antibody-dependent enhancement(ADE).

Research on the potential mechanism of Huashi Baidu Recipe against novel coronavirus pneumonia(COVID-19)by network pharmacology and molecular docking technology

Objective:Use network pharmacology to explore the anti-COVID-19 mechanism of Huashi Baidu Recipe,supplemented by molecular docking verification.Methods:Thorugh databases such as TCMSP,GeneCard,String,and software such as Cytoscape,AutoDockVina,network relationships was established,and the binding ability of active ingredients and targets is calculated through molecular docking,and biological function enrichment analysis was conducted.Result:The ingredients in Huashi Baidu Recipe that had strong affinity with SARS-CoV-23CL hydrolase(3CLpro)and angiotensin converting enzyme 2(ACE2)receptors include Quercetin,Baicalein,Astragaloside IV,Wogonin and other ingredients;25 active ingredients which obtained by screening had strong affinity with targets such as IL6,IL1B,NOS2 and CCL2.The biological function enrichment analysis mainly focused on Th17,Th1 and Th2 cell differentiation,NF-κB,MAPK,TNF,IL-17signaling pathway,etc.Conclusion:The active ingredients of Huashi Baidu Recipe may inhibit the infection and replication of SARS-CoV-2 virus,regulate RAS system’balance,inhibit excessive immune inflammatory response,and prevent inflammatory storm from appearing to fight COVID-19.

Potential mechanism of Xuanfei Baidu Formula in treating new coronavirus pneumonia based on network pharmacology and molecular docking

Objective:To investigate the molecular mechanism of antiviral effect of Xuanfei Baidu Formula in the treatment of coronavirus disease 2019(COVID-19),and to provide reference for the twreatment of COVID-19 with traditional Chinese medicine.Methods:Traditional Chinese Medicine Systems Pharmacology(TCMSP)was employed to search the effective active component and targets of Xuanfei Baidu Formula.Databases,GeneCards etc.were employed to obtain the relevant target genes of COVID-19 and intersect with the targets of Xuanfei Baidu Formula to obtain the therapeutic targets.The therapeutic targets were uploaded to the STRING database to obtain protein interaction(PPI)information,and Cytoscape was utilized to construct drug-target-disease networks,high-confidence PPI networks for target proteins,and active-target-pathway networks.GO,gene ontology,functional analysis and KEGG(Kyoto Encyclopedia of Genes and Genomes)pathway enrichment analysis of potential targets of action were performed using the R package in Bioconductor.The main active components were molecular docking technology with 3C-like protease(3CLPro)and angiotensin-cinverting enzyme2(ACE2)and key targets of SARS-CoV-2,respectively.Results:A total of 99 effective active ingredients of Xuanfei Baidu Formula were selected,of which 22 active ingredients acting on COVID-19 could act on COVID-19 through 52 potential targets.Enrichment yielded 1,364 biological process entries and 22 KEGG pathways in GO,involving paths such as IL-17,JAK-STAT,MAPK,NF-κB,PI3K-Akt,Th1 and Th2 cell differentiation,Th17 cell differentiation,T cell receptor,vascular endothelial growth factor(VEGF)and Salmonella infection.Molecular docking technology results revealed that active components such as luteolin,beta-sitostero,formononetin,and shinpterocarpin in Xuanfei Baidu Formula embraced satisfactory binding to 3CLPro and ACE2,and also had good binding to core targets.Conclusion:Xuanfei Baidu Formula inhibits viral invasion and viral replication mainly by binding to ACE2 and 3CLPro receptors of SARS-CoV-2 through flavonoids and phytosterols,and may play a role in the treatment of COVID-19 by regulating key targets such as IL6,MAPK3,MAPK1,IL1β,CCL2,EGFR,and NOS2 after virus infection of cells,exerting anti-cytokine storm,anti-oxidation,and regulating the body's immunity.

Hidden in the hands-the special inner Bagua acupoints for pediatric massage

Pediatric massage is one of the external treatment methods that can improve children'sconstitution and immunity by regulating the viscera (the basic organs in traditonal Chinesemedicine theory), dredging the meridians, regulating Qi and blood, and balancing Yin and Yang.As one of the specific acupoints of pediatric massage, inner Bagua acupoint (one of the clinicallyused acupoints in children's massage that locate in the palm of the hand and the periphery ofthe palm) play a key role. Inner Bagua acupoints are the commonly used acupoints in pediatricmassage, which have the function of regulating Qi and eliminating phlegm (a kind pathologicfluid in TCM theory) and improving digestion. Inner Bagua acupoints have a unique curativeeffect on many diseases of digestive and respiratory system in children. Therefore, this articleattempts to elaborate and summarize the origin, location, operation and clinical application ofthe inner Bagua acupoints. This article hopes to provide a basis information for advocating anddisseminating pediatric massage, which is favorable for wide-range popularization anddevelopment.

硫化钠体系中异极矿表面的硫化特性及硫化产物解析

通过多种分析检测方法揭示硫化钠体系中异极矿表面的硫化特性和机理,并对异极矿表面硫化产物进行分析测试。研究结果表明,硫化钠浓度对异极矿表面的硫化效果具有显著影响,即提高硫化钠浓度能促进矿浆溶液中硫组分与矿物表面反应,从而提高异极矿表面硫化产物的含量及矿物表面的疏水性。XPS和ToF-SIMS分析表明,异极矿表面的硫化产物并非单一的硫化物,而是由硫化物(S^(2−))和多硫化物(S_(n)^(2−))组成,且矿物表面多硫化物含量随硫化钠浓度的增加而增加,从而增强异极矿表面硫化产物的活性。

An Experimental Research of Natural Circulation Heat Transfer for PRHR Heat Exchanger in AP1000

The heat transfer characteristics of the PRHR （passive residual heat removal） HX （heat exchanger） are very important to reactor design and safety assessment of AP1000. The purpose of the present experiment was to obtain the natural circulation data in HX to research the heat transfer behavior. The PRHR HX was simulated by three C-type tubes with prototype sizes immerged in a cooling tank. Separate-effect tests of natural circulation in HX tubes have been performed within wide conditions which could cover the operation conditions in AP1000. The experiment provided lots of important data to indicate heat transfer phenomena of PRHR HX. The test conditions were calculated by RELAP5/MOD3.3. The calculation results agreed well with the experiment. RELAP5 could be applied with proper correlations to analyze the heat transfer in PRHR HX under the test conditions.

Role of bitter contributors and bitter taste receptors:a comprehensive review of their sources,functions and future development

Bitterness,one of the 5“basic tastes”,is usually undesired by humans.However,abundant literature reported that bitter fruits and vegetables have beneficial health effects due to their bitter contributors.This review provided an updated overview of the main bitter contributors of typical bitter fruits and vegetables and their health benefits.The main bitter contributors,including phenolics,terpenoids,alkaloids,amino acids,nucleosides and purines,were summarized.The bioactivities and wide range of beneficial effects of them on anti-cancers,anti-inflammations,anti-microbes,neuroprotection,inhibiting chronic and acute injury in organs,as well as regulating behavior performance and metabolism were reported.Furthermore,not only did the bitter taste receptors(taste receptor type 2 family,T2Rs)show taste effects,but extra-oral T2Rs could also be activated by binding with bitter components,regulating physiological activities via modulating hormone secretion,immunity,metabolism,and cell proliferation.This review provided a new perspective on exploring and explaining the nutrition of bitter foods,revealing the relationship between the functions of bitter contributors from food and T2Rs.Future trends may focus on revealing the possibility of T2Rs being targets for the treatment of diseases,exploring the mechanism of T2Rs mediating the bioactivities,and making bitter foods more acceptable without getting rid of bitter contributors.

Nitrogen application regulates antioxidant capacity and flavonoid metabolism,especially quercetin,in grape seedlings under salt stress

Salt stress is a typical abiotic stress in plants that causes slow growth,stunting,and reduced yield and fruit quality.Fertilization is necessary to ensure proper crop growth.However,the effect of fertilization on salt tolerance in grapevine is unclear.In this study,we investigated the effect of nitrogen fertilizer(0.01 and 0.1 mol L^(-1)NH_(4)NO_(3))application on the salt(200 mmol L^(-1)NaCl)tolerance of grapevine based on physiological indices,and transcriptomic and metabolomic analyses.The results revealed that 0.01 mol L^(-1)NH_(4)NO_(3) supplementation significantly reduced the accumulation of superoxide anion(O_(2)^(-)·),enhanced the activities of superoxide dismutase(SOD)and peroxidase(POD),and improved the levels of ascorbic acid(AsA)and glutathione(GSH)in grape leaves compared to salt treatment alone.Specifically,joint transcriptome and metabolome analyses showed that the differentially expressed genes(DEGs)and differentially accumulated metabolites(DAMs)were significantly enriched in the flavonoid biosynthesis pathway(ko00941)and the flavone and flavonol biosynthesis pathway(ko00944).In particular,the relative content of quercetin(C00389)was markedly regulated by salt and nitrogen.Further analysis revealed that exogenous foliar application of quercetin improved the SOD and POD activities,increased the AsA and GSH contents,and reduced the H_(2)O_(2) and O_(2)^(-)·contents.Meanwhile,10 hub DEGs,which had high Pearson correlations(R^(2)>0.9)with quercetin,were repressed by nitrogen.In conclusion,all the results indicated that moderate nitrogen and quercetin application under salt stress enhanced the antioxidant system defense response,thus providing a new perspective for improving salt tolerance in grapes.