The synchronous virtual machine uses inverter power to imitate the performance of the conventional synchronous machine.It also has the same inertia,damping,frequency,voltage regulation,and other external performance a...The synchronous virtual machine uses inverter power to imitate the performance of the conventional synchronous machine.It also has the same inertia,damping,frequency,voltage regulation,and other external performance as the generator.It is the key technology to realize new energy grid connections’stable and reliable operation.This project studies a dynamic simulation model of an extensive new energy power system based on the virtual synchronous motor.A new energy storage method is proposed.The mathematical energy storage model is established by combining the fixed rotor model of a synchronous virtual machine with the charge-discharge power,state of charge,operation efficiency,dead zone,and inverter constraint.The rapid conversion of energy storage devices absorbs the excess instantaneous kinetic energy caused by interference.The branch transient of the critical cut set in the system can be confined to a limited area.Thus,the virtual synchronizer’s kinetic and potential energy can be efficiently converted into an instantaneous state.The simulation of power system analysis software package(PSASP)verifies the correctness of the theory and algorithm in this paper.This paper provides a theoretical basis for improving the transient stability of new energy-connected power grids.展开更多
Glabridin is the main ingredient of hydrophobic fraction in licorice extract and has been shown to have anti-melanogenesis activity in skins.However,the underlying mechanism(s)remain not completely understood.The aim ...Glabridin is the main ingredient of hydrophobic fraction in licorice extract and has been shown to have anti-melanogenesis activity in skins.However,the underlying mechanism(s)remain not completely understood.The aim of this study is thus to elucidate the possible mechanisms related to the melanogenesis suppression by glabridin in cultured B16 murine melanoma cells and in UVA radiation induced hyperpigmentation model of BALB/c mice as well.Molecular docking simulations revealed that between catalytic core residues and the compound.The treatment by glabridin significantly downregulated both transcriptional and/or protein expression of melanogenesis-related factors including melanocyte stimulating hormone receptor(MC1R),microphthalmia-associated transcription factor(MITF),tyrosinase(TYR),TYR-related protein-1(TRP-1)and TRP-2 in B16 cells.Both PKA/MITF and MAPK/MITF signaling pathways were found to be involved in the suppression of melanogenesis by glabridin in B16 cells.Also in vivo glabridin therapy significantly reduced hyperpigmentation,epidermal thickening,roughness and inflammation induced by frequent UVA exposure in mice skins,thus beneficial for skin healthcare.These data further look insights into the molecular mechanisms of melanogenesis suppression by glabridin,rationalizing the application of the natural compound for skin healthcare.展开更多
Axial flux permanent magnet synchronous motors(AFPMSMs)have been widely used in wind-power generation,electric vehicles,aircraft,and other renewable-energy applications owing to their high power density,operating effi...Axial flux permanent magnet synchronous motors(AFPMSMs)have been widely used in wind-power generation,electric vehicles,aircraft,and other renewable-energy applications owing to their high power density,operating efficiency,and integrability.To facilitate comprehensive research on AFPMSM,this article reviews the developments in the research on the design and control optimization of AFPMSMs.First,the basic topologies of AFPMSMs are introduced and classified.Second,the key points of the design optimization of core and coreless AFPMSMs are summarized from the aspects of parameter design,structure design,and material optimization.Third,because efficiency improvement is an issue that needs to be addressed when AFPMSMs are applied to electric or other vehicles,the development status of efficiency-optimization control strategies is reviewed.Moreover,control strategies proposed to suppress torque ripple caused by the small inductance of disc coreless permanent magnet synchronous motors(DCPMSMs)are summarized.An overview of the rotor-synchronization control strategies for disc contra-rotating permanent magnet synchronous motors(CRPMSMs)is presented.Finally,the current difficulties and development trends revealed in this review are discussed.展开更多
Magnesium alloys,the advanced lightweight structural materials,have been successfully applied in the manufacturing field.Unfortunately,their poor corrosion resistance restrains the potential wide applications.In this ...Magnesium alloys,the advanced lightweight structural materials,have been successfully applied in the manufacturing field.Unfortunately,their poor corrosion resistance restrains the potential wide applications.In this work,anti-corrosion coatings were fabricated via the insitu growth of the corrosion inhibitors intercalated magnesium-aluminum layered double hydroxide(Mg-Al LDH)on AZ31 magnesium alloy and then post-sealing it by a super-hydrophobic coating.SEM,XRD,EDS,FTIR,XPS and contact angle test were conducted to analyze physical/chemical features of these coatings.Potentiodynamic polarization curves and electrochemical impedance spectroscopy were recorded to assess the anti-corrosion performance of prepared coatings.Surprisingly,Mg-Al LDH with molybdate intercalation and lauric acid modification achieves the excellent corrosion inhibition performance(99.99%)due to the multicomponent synergistic effect such as the physical protection of Mg-Al LDH,the corrosion inhibition of molybdate and super-hydrophobic properties of lauric acid.This work presents a scientific perspective and novel design philosophy to fabricate the efficient anti-corrosion coating to protect magnesium alloys and then expand their potential applications in other field.展开更多
Due to the easily controllable interlayer anions, metal cation composition proportion and thickness, which is beneficial to modify surface chemical state and tune bandgap, layered double hydroxides(LDHs) have great pr...Due to the easily controllable interlayer anions, metal cation composition proportion and thickness, which is beneficial to modify surface chemical state and tune bandgap, layered double hydroxides(LDHs) have great promising potential for photocatalytic applications. In this study,we have successfully synthesized the ZnAl–LDH intercalated the single anion between ZnAl cationic interlayer without anionic impurities by using a facile calcining and reconstructing routes. The electron structure and surface chemical state of the prepared products have been investigated by combining the DFT calculation and experimental characterization methods. UV–vis DRS was used to certify the light absorption of the prepared products, and we performed the DFT calculation to demonstrate the density of state and activation of reactant. These results suggested that the ZnAl–LDH–CO3 possessed the more proper band structure and superior ability to activate NO and O2 for accelerating the photocatalytic NO oxidation activity. Moreover, the in situ DRIFTS with dynamically monitoring intermediates and products over the ZnAl–LDH–CO3 was adopted to declare the photocatalytic NO oxidized process during the photocatalytic reaction process. This work illustrated the influence of different interlayer anions to the electron structure and surface chemical state of ZnAl–LDH structure through the experimental verification combined DFT calculation and the photocatalytic NO oxidized process via in situ DRIFTS analyzing, which would provide a novel way to design and fabricate the efficient photocatalysis, and understand the reaction process.展开更多
Cobalt-Aluminum layered double hydroxide(CoAl LDH) is a hopeful electrode material due to the advantage of easy modifiability for preparing LDH-based derivatives.However,there is short of modification methods to prepa...Cobalt-Aluminum layered double hydroxide(CoAl LDH) is a hopeful electrode material due to the advantage of easy modifiability for preparing LDH-based derivatives.However,there is short of modification methods to prepare the Co-based derivatives from CoAl LDH and also short of an intuitive perspective to analyze the pseudocapacitance mechanism of CoAl LDH and its derivatives.Herein,Graphene/CoAl LDH and its derivatives including Graphene/CoS,Graphene/CoS-1,Graphene/CoOOH,Graphene/CoP were prepared by reasonably using alkali etching treatment,sulfofication and phosphorization.The specific capacitance of Graphene/CoAl LDH,Graphene/CoS,Graphene/CoS-1,Graphene/CoOOH,Graphene/CoP at1 A g^(-1) are 260.7,371.3,440.8,61.4 and 122.2 F g^(-1),especially.The pseudocapacitance mechanism of Graphene/CoAl LDH and its derivatives was analyzed.Due to the positive effect of sulfofication on the electrical conductivity of GO and cobalt sulfide,the Graphene/CoS and Graphene/CoS-1 exhibit the optimal electrochemical performance and superior rate capability.In addition,due to the repulsion effect between Graphene and OH-,the Graphene/CoAl LDH exhibits optimal cycling stability of 224.1% capacitance retention after 20000 cycles.Besides,the reason of terrible specific capacitance of Graphene/CoOOH is that the presence of H bond in interlayer of CoOOH inhibits the interaction between Co3+ and OHspecies.Hence,not all modifications will increase the specific capacitance of the electrode materials.Overall,this work provides us with a detailed analysis of the electrochemical mechanism and correlation of CoAl LDH and its derivatives from the perspective of crystal structure and composition.展开更多
Compound light is required for plant growth and development,but the response mechanisms of plants are undercharacterized and not fully understood.The present study was undertaken to evaluate the effect of supplemental...Compound light is required for plant growth and development,but the response mechanisms of plants are undercharacterized and not fully understood.The present study was undertaken to evaluate the effect of supplemental light(green light,G;white light,W;yellow light,Y)added to red–blue light(RB)and sole W on the growth and photosynthesis of rapeseed seedlings.The results revealed that supplemental G/W improved the growth and photosynthesis of seedlings,but supplemental Y significantly reduced the photosynthetic rate and palisade tissue layer.Sole W caused similar responses in terms of growth,leaf development,oxidative damage,and antioxidant capability as supplemental Y.In total,449,367,813,and 751 differentially expressed genes(DEGs)were identified under supplemental G,Y,and W and sole W,respectively,compared to RB.The DEGs under different lights were closely associated with pathways such as light stimulus and high-light response,root growth,leaf development,photosynthesis,photosynthesis-antenna proteins,carbohydrate synthesis and degradation,secondary metabolism,plant hormones,and antioxidant capacity,which contributed to the distinct growth and photosynthesis under different treatments.Our results suggest that Y is more likely substituted by other wavelengths to achieve certain effects similar to those of supplemental Y,while G has a more distinctive effect on rapeseed.Taken together,supplementation RB with G/W promotes the growth of rapeseed seedlings in a controlled environment.展开更多
High electrochemically active bimessite is always desirable pseudocapacitive material for supercapacitor.Here,two-dimensional(2D)compulsive malposition parallel bimessite standing on β-MnO_(2) interconnected networks...High electrochemically active bimessite is always desirable pseudocapacitive material for supercapacitor.Here,two-dimensional(2D)compulsive malposition parallel bimessite standing on β-MnO_(2) interconnected networks have been designed.Due to the retrition of β-MnO_(2),compulsi ve malposition,slippage of MnO6 slab,occured in bimessite resulting in weaken bi nding force between bimessi te slab and interlayer cations,which enhanced their electrochemical performances.Additionally,the electrical conductivity of the structure was largely promoted by the 2D charge transfer route and double-exchange mechanism in bimessite,also leading to desirable electro-chemical properties.Based on the fraction of as-prepared nanostructure,the par all bimessite exhibited good pseudocapacitance performance(660 F g^(-1))with high rate capability.In addition,the asymmetrice supercapacitor assembled by reduced graphene oxide(RGO)and as-prepared nanostructure,which respectively served as the negative and positive eletrode,delivered an energy density of 33.1 Wh kg^(-1) and a mad mum power density of 64.0 kW kg^(-1) with excellent cyeling stability(95.8% after 10000 cycles).Finally,the study opens new avenwes for synthesizing high eletrochemically actiwe bimessite structure for high-performance energy storage devices.展开更多
Neutrophils constitute a significant portion of the immune cells present within the tumor microenvironment.Evidence generated by our group has confirmed neutrophils to be an adverse independent prognostic factor affec...Neutrophils constitute a significant portion of the immune cells present within the tumor microenvironment.Evidence generated by our group has confirmed neutrophils to be an adverse independent prognostic factor affecting the disease-free survival of gastric carcinoma(GC)patients.1 Neutrophil extracellular traps(NETs),protein-covered DNA webs that interact with tumor cells in the tumor microenvironment,were detected in GC tissues and found to clinically associated with disease progression in our previous study.2 NETosis could be mediated by a series of agonists,such as interleukin 8(IL-8).3 However,the mechanism of IL-8 in the progression of GC occurs via NETs remains unclear.In this study,we identified that IL-8-mediated NETosis can promote the proliferation,migration,and invasion of GC cells in vitro,which can be abrogated by NET degradation through deoxyribonucleaseI(DNase I)or IL-8 suppression through neutralizing antibodies.Disruption of NETs by DNase I or blockade of the IL-8-CXC chemokine receptor 2(CXCR2)axis could result in growth retardation in mouse models.We also confirmed that NETs may influence the biological behavior of GC cells by up-regulating the expression of transcription factor IB-related factor 1(BRF1)and cyclin p21/p27.展开更多
Lunar soil preserves numerous fragments of meteorites impacting on the Moon,providing a unique opportunity to investigate the distribution of the types of projectiles over billions of years.Here we report the first di...Lunar soil preserves numerous fragments of meteorites impacting on the Moon,providing a unique opportunity to investigate the distribution of the types of projectiles over billions of years.Here we report the first discovery of an iron meteorite fragment from the Chang’e-5 lunar soil,which consists mainly of martensite(quenched from taenite),kamacite,and schreibersite,with a trace of pentlandite.The meteorite fragment is Ni-and P-rich,S-poor,and based on its mineral chemistry and bulk composition,can be classified into the IID-group,a rare and carbonaceous group of iron meteorite originating in the outer Solar System.This meteorite fragment experienced only limited partial melting followed by fast cooling,suggestive of efficient preservation of intact remnants of iron meteorites impacting on the porous lunar regolith.Alternatively,it is a relic of a low-velocity impact of submillimeter-sized metal grains originated from an IID-like iron meteorite.Our observations demonstrate that it is feasible to achieve the type distribution of meteorites impacting on the Moon via systematically analyzing a large number of metal grains separated from lunar soils,thus shedding light on the dynamic evolution of the Solar System.展开更多
Kiwifruit is a recently domesticated horticultural fruit crop with substantial economic and nutritional value,especially because of the high content of vitamin C in its fruit.In this study,we de novo assembled two tel...Kiwifruit is a recently domesticated horticultural fruit crop with substantial economic and nutritional value,especially because of the high content of vitamin C in its fruit.In this study,we de novo assembled two telomere-to-telomere kiwifruit genomes from Actinidia chinensis var.‘Donghong’(DH)and Actinidia latifolia‘Kuoye’(KY),with total lengths of 608327852 and 640561626 bp for 29 chromosomes,respectively.With a burst of structural variants involving inversion,translocations,and duplications within 8.39 million years,the metabolite content of DH and KY exhibited differences in saccharides,lignans,and vitamins.A regulatory ERF098 transcription factor family has expanded in KY and Actinidia eriantha,both of which have ultra-high vitamin C content.With each assembly phased into two complete haplotypes,we identified allelic variations between two sets of haplotypes,leading to protein sequence variations in 26494 and 27773 gene loci and allele-specific expression of 4687 and 12238 homozygous gene pairs.Synchronized metabolome and transcriptome changes during DH fruit development revealed the same dynamic patterns in expression levels and metabolite contents;free fatty acids and flavonols accumulated in the early stages,but sugar substances and amino acids accumulated in the late stages.The AcSWEET9b gene that exhibits allelic dominance was further identified to positively correlate with high sucrose content in fruit.Compared with wild varieties and other Actinidia species,AcSWEET9b promoters were selected in red-flesh kiwifruits that have increased fruit sucrose content,providing a possible explanation on why red-flesh kiwifruits are sweeter.Collectively,these two gap-free kiwifruit genomes provide a valuable genetic resource for investigating domestication mechanisms and genome-based breeding of kiwifruit.展开更多
The methylation of lysine 4 of histone H3(H3K4),catalyzed by the histone methyltransferase KMT2/SET1,has been functionally identified in many pathogenic fungi but remains unexplored in nematode-trapping fungi(NTFs).He...The methylation of lysine 4 of histone H3(H3K4),catalyzed by the histone methyltransferase KMT2/SET1,has been functionally identified in many pathogenic fungi but remains unexplored in nematode-trapping fungi(NTFs).Here,we report a regulatory mechanism of an H3K4-specific SET1 orthologue,AoSET1,in the typical nematode-trapping fungus Arthrobotrys oligospora.When the fungus is induced by the nematode,the expression of AoSET1 is up-regulated.Disruption of AoSet1 led to the abolishment of H3K4me.Consequently,the yield of traps and conidia ofΔAoSet1 was significantly lower than that of the WT strain,and the growth rate and pathogenicity were also compromised.Moreover,H3K4 trimethylation was enriched mainly in the promoter of two bZip transcription factor genes(AobZip129 and AobZip350)and ultimately up-regulated the expression level of these two transcription factor genes.In theΔAoSet1 and AoH3K4A strains,the H3^(K4)me modification level was significantly decreased at the promoter of transcription factor genes AobZip129 and AobZip350.These results suggest that AoSET1-mediated H3KEme serves as an epigenetic marker of the promoter region of the targeted transcription factor genes.Furthermore,we found that AobZip129 negatively regulates the formation of adhesive networks and the pathogenicity of downstream AoPABP1 and AoCPR1.Our findings confirm that the epigenetic regulatory mechanism plays a pivotal role in regulating trap formation and pathogenesis in NTFs,and provide novel insights into the mechanisms of interaction between NTFs and nematodes.展开更多
Intensive selective breeding for high growth rate and body weight cause excess abdominal fat in broilers.Gut microbiota and folic acid were reported to regulate lipid metabolism.A total of 210 one-day-old broilers wer...Intensive selective breeding for high growth rate and body weight cause excess abdominal fat in broilers.Gut microbiota and folic acid were reported to regulate lipid metabolism.A total of 210 one-day-old broilers were divided into the control(folic acid at 1.3 mg/kg)and folic acid groups(folic acid at 13 mg/kg)to illustrate the effects of folic acid on growth performance,abdominal fat deposition,and gut microbiota,and the experiment lasted 28 d.Results revealed that dietary folic acid addition decreased abdominal fat percentage(P<0.05)and down-regulated genes expression related to cell proliferation and differentiation in abdominal fat including IGF1,EGF,C/EBPα,PPARγ,PLIN1,FABP4 and PCNA(P<0.05).Folic acid addition decreased caecal Firmicutes-to-Bacteroidetes ratio(P<0.01)and increased the proportions of Alistipes,Oscillospira,Ruminococcus,Clostridium,Dehalobacterium and Parabacteroides(P<0.05).Caecal acetic acid,and propionic acid contents were found to be higher under folic acid treatment(P<0.05),which were negatively related to genes expression associated with adipocyte proliferation and differentiation(P<0.05).Ruminococcus was positively correlated with caecal acetic acid content,and the same phenomenon was detected between propionic acid and Oscillospira and Ruminococcus(P<0.05).Acetic acid and Oscillospira were identified to be negatively associated with abdominal fat percentage(P<0.05).In conclusion,our data demonstrated that dietary supplementation of folic acid reduced fat deposition in broilers by inhibiting abdominal adipocyte proliferation and differentiation,which might be mediated by changes in gut microbiota and short chain fatty acid production.展开更多
Pediatric cough is a heterogeneous condition in terms of symptoms and the underlying disease mechanisms.Symptom phenotypes hold complicated interactions between each other to form an intricate network structure.This s...Pediatric cough is a heterogeneous condition in terms of symptoms and the underlying disease mechanisms.Symptom phenotypes hold complicated interactions between each other to form an intricate network structure.This study aims to investigate whether the network structure of pediatric cough symptoms is associated with the prognosis and outcome of patients.A total of 384 cases were derived from the electronic medical records of a highly experienced traditional Chinese medicine (TCM) physician.The data were divided into two groups according to the therapeutic effect,namely,an invalid group (group A with 40 cases of poor efficacy) and a valid group (group B with 344 cases of good efficacy).Several well-established analysis methods,namely,statistical test,correlation analysis,and complex network analysis,were used to analyze the data.This study reports that symptom networks of patients with pediatric cough are related to the effectiveness of treatment: a dense network of symptoms is associated with great difficulty in treatment.Interventions with the most different symptoms in the symptom network may have improved therapeutic effects.展开更多
文摘The synchronous virtual machine uses inverter power to imitate the performance of the conventional synchronous machine.It also has the same inertia,damping,frequency,voltage regulation,and other external performance as the generator.It is the key technology to realize new energy grid connections’stable and reliable operation.This project studies a dynamic simulation model of an extensive new energy power system based on the virtual synchronous motor.A new energy storage method is proposed.The mathematical energy storage model is established by combining the fixed rotor model of a synchronous virtual machine with the charge-discharge power,state of charge,operation efficiency,dead zone,and inverter constraint.The rapid conversion of energy storage devices absorbs the excess instantaneous kinetic energy caused by interference.The branch transient of the critical cut set in the system can be confined to a limited area.Thus,the virtual synchronizer’s kinetic and potential energy can be efficiently converted into an instantaneous state.The simulation of power system analysis software package(PSASP)verifies the correctness of the theory and algorithm in this paper.This paper provides a theoretical basis for improving the transient stability of new energy-connected power grids.
基金supported by the Inner Mongolia Autonomous Region Science and Technology Revitalization Foundation (2021CG0029)the National Natural Science Foundation of China (22178070)
文摘Glabridin is the main ingredient of hydrophobic fraction in licorice extract and has been shown to have anti-melanogenesis activity in skins.However,the underlying mechanism(s)remain not completely understood.The aim of this study is thus to elucidate the possible mechanisms related to the melanogenesis suppression by glabridin in cultured B16 murine melanoma cells and in UVA radiation induced hyperpigmentation model of BALB/c mice as well.Molecular docking simulations revealed that between catalytic core residues and the compound.The treatment by glabridin significantly downregulated both transcriptional and/or protein expression of melanogenesis-related factors including melanocyte stimulating hormone receptor(MC1R),microphthalmia-associated transcription factor(MITF),tyrosinase(TYR),TYR-related protein-1(TRP-1)and TRP-2 in B16 cells.Both PKA/MITF and MAPK/MITF signaling pathways were found to be involved in the suppression of melanogenesis by glabridin in B16 cells.Also in vivo glabridin therapy significantly reduced hyperpigmentation,epidermal thickening,roughness and inflammation induced by frequent UVA exposure in mice skins,thus beneficial for skin healthcare.These data further look insights into the molecular mechanisms of melanogenesis suppression by glabridin,rationalizing the application of the natural compound for skin healthcare.
基金Supported by Shanghai Municipal Natural Science Foundation of China (Grant No.19ZR1418600)。
文摘Axial flux permanent magnet synchronous motors(AFPMSMs)have been widely used in wind-power generation,electric vehicles,aircraft,and other renewable-energy applications owing to their high power density,operating efficiency,and integrability.To facilitate comprehensive research on AFPMSM,this article reviews the developments in the research on the design and control optimization of AFPMSMs.First,the basic topologies of AFPMSMs are introduced and classified.Second,the key points of the design optimization of core and coreless AFPMSMs are summarized from the aspects of parameter design,structure design,and material optimization.Third,because efficiency improvement is an issue that needs to be addressed when AFPMSMs are applied to electric or other vehicles,the development status of efficiency-optimization control strategies is reviewed.Moreover,control strategies proposed to suppress torque ripple caused by the small inductance of disc coreless permanent magnet synchronous motors(DCPMSMs)are summarized.An overview of the rotor-synchronization control strategies for disc contra-rotating permanent magnet synchronous motors(CRPMSMs)is presented.Finally,the current difficulties and development trends revealed in this review are discussed.
基金supported by the Fundamental Research Funds for the Central Universities(2018CDYJSY0055)the National Natural Science Foundation of China(21576034)+3 种基金Joint Funds of the National Natural Science Foundation of China-Guangdong(U1801254)the project funded by Chongqing Special Postdoctoral Science Foundation(Xm T2018043)Technological projects of Chongqing Municipal Education Commission(KJZDK201800801)the Innovative Research Team of Chongqing(CXTDG201602014)~~
基金This work is financially supported by the Graduate Research and Innovation of Chongqing,China(Grant No.CYB18002)the National Natural Science Foundation of China(Grant No.21576034)+2 种基金the State Education Ministry and Fundamental Research Funds for the Central Universities(2019CDQYCL042,106112017CDJXSYY0001,2018CDYJSY0055,106112017CDJQJ138802,106112017CDJSK04XK11,2018CDQYCL0027)the Joint Funds of the National Natural Science Foundation of China-Guangdong(Grant No.U1801254)Fundamental Re-search Funds for the Central Universities(NO.2018CDJDCD0001).
文摘Magnesium alloys,the advanced lightweight structural materials,have been successfully applied in the manufacturing field.Unfortunately,their poor corrosion resistance restrains the potential wide applications.In this work,anti-corrosion coatings were fabricated via the insitu growth of the corrosion inhibitors intercalated magnesium-aluminum layered double hydroxide(Mg-Al LDH)on AZ31 magnesium alloy and then post-sealing it by a super-hydrophobic coating.SEM,XRD,EDS,FTIR,XPS and contact angle test were conducted to analyze physical/chemical features of these coatings.Potentiodynamic polarization curves and electrochemical impedance spectroscopy were recorded to assess the anti-corrosion performance of prepared coatings.Surprisingly,Mg-Al LDH with molybdate intercalation and lauric acid modification achieves the excellent corrosion inhibition performance(99.99%)due to the multicomponent synergistic effect such as the physical protection of Mg-Al LDH,the corrosion inhibition of molybdate and super-hydrophobic properties of lauric acid.This work presents a scientific perspective and novel design philosophy to fabricate the efficient anti-corrosion coating to protect magnesium alloys and then expand their potential applications in other field.
基金financial support of the Fundamental Research Funds for the Central Universities (2018CDYJSY0055, 106112017CDJXSYY0001, 106112017C DJQJ138802, 106112017CDJXSYY0001, 106112017CDJS K04XK11, and 2018CDQYCL0027)the National Natural Science Foundation of China (Grant no. 21576034)+2 种基金the Innovative Research Team of Chongqing (CXTDG201602014)Project funded by Chongqing Special Postdoctoral Science Foundation (XmT2018043)Technological projects of Chongqing Municipal Education Commission (KJZDK201800801)
文摘Due to the easily controllable interlayer anions, metal cation composition proportion and thickness, which is beneficial to modify surface chemical state and tune bandgap, layered double hydroxides(LDHs) have great promising potential for photocatalytic applications. In this study,we have successfully synthesized the ZnAl–LDH intercalated the single anion between ZnAl cationic interlayer without anionic impurities by using a facile calcining and reconstructing routes. The electron structure and surface chemical state of the prepared products have been investigated by combining the DFT calculation and experimental characterization methods. UV–vis DRS was used to certify the light absorption of the prepared products, and we performed the DFT calculation to demonstrate the density of state and activation of reactant. These results suggested that the ZnAl–LDH–CO3 possessed the more proper band structure and superior ability to activate NO and O2 for accelerating the photocatalytic NO oxidation activity. Moreover, the in situ DRIFTS with dynamically monitoring intermediates and products over the ZnAl–LDH–CO3 was adopted to declare the photocatalytic NO oxidized process during the photocatalytic reaction process. This work illustrated the influence of different interlayer anions to the electron structure and surface chemical state of ZnAl–LDH structure through the experimental verification combined DFT calculation and the photocatalytic NO oxidized process via in situ DRIFTS analyzing, which would provide a novel way to design and fabricate the efficient photocatalysis, and understand the reaction process.
基金the financial support provided by the Graduate Research and innovation of Chongqing, China (Grant No. CYB18002)the National Natural Science Foundation of China (Grant No. 21576034 and 51908092)+1 种基金the State Education Ministry and Fundamental Research Funds for the Central Universities (2019CDQYCL042, 2019CDXYCL0031, 106112017CDJXSYY0001, 2018CDYJSY0055, 106112017CDJQJ138802, 106112017CDJSK04XK11, and 2018CDQYCL0027)the Joint Funds of the National Natural Science Foundation of China-Guangdong (Grant No. U1801254)。
文摘Cobalt-Aluminum layered double hydroxide(CoAl LDH) is a hopeful electrode material due to the advantage of easy modifiability for preparing LDH-based derivatives.However,there is short of modification methods to prepare the Co-based derivatives from CoAl LDH and also short of an intuitive perspective to analyze the pseudocapacitance mechanism of CoAl LDH and its derivatives.Herein,Graphene/CoAl LDH and its derivatives including Graphene/CoS,Graphene/CoS-1,Graphene/CoOOH,Graphene/CoP were prepared by reasonably using alkali etching treatment,sulfofication and phosphorization.The specific capacitance of Graphene/CoAl LDH,Graphene/CoS,Graphene/CoS-1,Graphene/CoOOH,Graphene/CoP at1 A g^(-1) are 260.7,371.3,440.8,61.4 and 122.2 F g^(-1),especially.The pseudocapacitance mechanism of Graphene/CoAl LDH and its derivatives was analyzed.Due to the positive effect of sulfofication on the electrical conductivity of GO and cobalt sulfide,the Graphene/CoS and Graphene/CoS-1 exhibit the optimal electrochemical performance and superior rate capability.In addition,due to the repulsion effect between Graphene and OH-,the Graphene/CoAl LDH exhibits optimal cycling stability of 224.1% capacitance retention after 20000 cycles.Besides,the reason of terrible specific capacitance of Graphene/CoOOH is that the presence of H bond in interlayer of CoOOH inhibits the interaction between Co3+ and OHspecies.Hence,not all modifications will increase the specific capacitance of the electrode materials.Overall,this work provides us with a detailed analysis of the electrochemical mechanism and correlation of CoAl LDH and its derivatives from the perspective of crystal structure and composition.
基金supported by the National Key R&D Program of China[grant number 2017YFB0403903]the National 863 High Technology Program of China[grant number 2013AA103003]the Student Research Training Project of Nanjing Agricultural University[grant number 1003A13].
文摘Compound light is required for plant growth and development,but the response mechanisms of plants are undercharacterized and not fully understood.The present study was undertaken to evaluate the effect of supplemental light(green light,G;white light,W;yellow light,Y)added to red–blue light(RB)and sole W on the growth and photosynthesis of rapeseed seedlings.The results revealed that supplemental G/W improved the growth and photosynthesis of seedlings,but supplemental Y significantly reduced the photosynthetic rate and palisade tissue layer.Sole W caused similar responses in terms of growth,leaf development,oxidative damage,and antioxidant capability as supplemental Y.In total,449,367,813,and 751 differentially expressed genes(DEGs)were identified under supplemental G,Y,and W and sole W,respectively,compared to RB.The DEGs under different lights were closely associated with pathways such as light stimulus and high-light response,root growth,leaf development,photosynthesis,photosynthesis-antenna proteins,carbohydrate synthesis and degradation,secondary metabolism,plant hormones,and antioxidant capacity,which contributed to the distinct growth and photosynthesis under different treatments.Our results suggest that Y is more likely substituted by other wavelengths to achieve certain effects similar to those of supplemental Y,while G has a more distinctive effect on rapeseed.Taken together,supplementation RB with G/W promotes the growth of rapeseed seedlings in a controlled environment.
基金the National Natural Science Foundation of China(Grant No.51908092)Projects(No.2020CDJXZ001,2020CDCGJ006 and 2020CDCGCL004)supported by the Fundamental Research Funds for the Central Universities,the Joint Funds of the National Natural Science Foundation of China-Guangdong(Grant No.U1801254)+5 种基金the project funded by Chongqing Special Postdoctoral Science Foundation(XmT2018043)the Chongqing Research Program of Basic Research and Frontier Technology(cstc2017jcyjBX0080)Natural Science Foundation Project of Chongqing for Post-doctor(cstc2019jcyjbsh0079,cstc2019jcyjbshX0085)Technological projects of Chongqing Municipal Education Commission(KJZDK201800801)the Innovative Research Team of Chongqing(CXTDG201602014)the Innovative technology of New materials and metallurgy(2019CDXYCL0031).
文摘High electrochemically active bimessite is always desirable pseudocapacitive material for supercapacitor.Here,two-dimensional(2D)compulsive malposition parallel bimessite standing on β-MnO_(2) interconnected networks have been designed.Due to the retrition of β-MnO_(2),compulsi ve malposition,slippage of MnO6 slab,occured in bimessite resulting in weaken bi nding force between bimessi te slab and interlayer cations,which enhanced their electrochemical performances.Additionally,the electrical conductivity of the structure was largely promoted by the 2D charge transfer route and double-exchange mechanism in bimessite,also leading to desirable electro-chemical properties.Based on the fraction of as-prepared nanostructure,the par all bimessite exhibited good pseudocapacitance performance(660 F g^(-1))with high rate capability.In addition,the asymmetrice supercapacitor assembled by reduced graphene oxide(RGO)and as-prepared nanostructure,which respectively served as the negative and positive eletrode,delivered an energy density of 33.1 Wh kg^(-1) and a mad mum power density of 64.0 kW kg^(-1) with excellent cyeling stability(95.8% after 10000 cycles).Finally,the study opens new avenwes for synthesizing high eletrochemically actiwe bimessite structure for high-performance energy storage devices.
基金supported by grants from The Natural Science Foundation of Anhui Province,China(No.1908085QH333)the Key Research and Development Project of Anhui Province,China(No.202004j07020044)+1 种基金the Natural Science Research Project of Anhui Provincial University(China)(No.KJ2018ZD019)Foundation of Beijing Life Oasis Public Service Center(China)(No.cphcf-2022-021).
文摘Neutrophils constitute a significant portion of the immune cells present within the tumor microenvironment.Evidence generated by our group has confirmed neutrophils to be an adverse independent prognostic factor affecting the disease-free survival of gastric carcinoma(GC)patients.1 Neutrophil extracellular traps(NETs),protein-covered DNA webs that interact with tumor cells in the tumor microenvironment,were detected in GC tissues and found to clinically associated with disease progression in our previous study.2 NETosis could be mediated by a series of agonists,such as interleukin 8(IL-8).3 However,the mechanism of IL-8 in the progression of GC occurs via NETs remains unclear.In this study,we identified that IL-8-mediated NETosis can promote the proliferation,migration,and invasion of GC cells in vitro,which can be abrogated by NET degradation through deoxyribonucleaseI(DNase I)or IL-8 suppression through neutralizing antibodies.Disruption of NETs by DNase I or blockade of the IL-8-CXC chemokine receptor 2(CXCR2)axis could result in growth retardation in mouse models.We also confirmed that NETs may influence the biological behavior of GC cells by up-regulating the expression of transcription factor IB-related factor 1(BRF1)and cyclin p21/p27.
基金supported by the National Natural Science Foundation of China(42230206,42241152,and 42103035)the Key Research Program of Frontier Sciences,Chinese Academy of Sciences(QYZDJ-SSW-DQC001).
文摘Lunar soil preserves numerous fragments of meteorites impacting on the Moon,providing a unique opportunity to investigate the distribution of the types of projectiles over billions of years.Here we report the first discovery of an iron meteorite fragment from the Chang’e-5 lunar soil,which consists mainly of martensite(quenched from taenite),kamacite,and schreibersite,with a trace of pentlandite.The meteorite fragment is Ni-and P-rich,S-poor,and based on its mineral chemistry and bulk composition,can be classified into the IID-group,a rare and carbonaceous group of iron meteorite originating in the outer Solar System.This meteorite fragment experienced only limited partial melting followed by fast cooling,suggestive of efficient preservation of intact remnants of iron meteorites impacting on the porous lunar regolith.Alternatively,it is a relic of a low-velocity impact of submillimeter-sized metal grains originated from an IID-like iron meteorite.Our observations demonstrate that it is feasible to achieve the type distribution of meteorites impacting on the Moon via systematically analyzing a large number of metal grains separated from lunar soils,thus shedding light on the dynamic evolution of the Solar System.
基金supported by the Provincial Technology Innovation Program of Shandongan award from the Natural Science Foundation of Shandong Province(ZR2021ZD30)+2 种基金the Director’s Award from the Peking University Institute of Advanced Agricultural Sciences,the National Top Young Talents Program of Chinathe Boya Postdoctoral Program of Peking University,the National Key R&D Program of China(2019YFD1000200)the Youth Innovation Promotion Association CAS(2018376).
文摘Kiwifruit is a recently domesticated horticultural fruit crop with substantial economic and nutritional value,especially because of the high content of vitamin C in its fruit.In this study,we de novo assembled two telomere-to-telomere kiwifruit genomes from Actinidia chinensis var.‘Donghong’(DH)and Actinidia latifolia‘Kuoye’(KY),with total lengths of 608327852 and 640561626 bp for 29 chromosomes,respectively.With a burst of structural variants involving inversion,translocations,and duplications within 8.39 million years,the metabolite content of DH and KY exhibited differences in saccharides,lignans,and vitamins.A regulatory ERF098 transcription factor family has expanded in KY and Actinidia eriantha,both of which have ultra-high vitamin C content.With each assembly phased into two complete haplotypes,we identified allelic variations between two sets of haplotypes,leading to protein sequence variations in 26494 and 27773 gene loci and allele-specific expression of 4687 and 12238 homozygous gene pairs.Synchronized metabolome and transcriptome changes during DH fruit development revealed the same dynamic patterns in expression levels and metabolite contents;free fatty acids and flavonols accumulated in the early stages,but sugar substances and amino acids accumulated in the late stages.The AcSWEET9b gene that exhibits allelic dominance was further identified to positively correlate with high sucrose content in fruit.Compared with wild varieties and other Actinidia species,AcSWEET9b promoters were selected in red-flesh kiwifruits that have increased fruit sucrose content,providing a possible explanation on why red-flesh kiwifruits are sweeter.Collectively,these two gap-free kiwifruit genomes provide a valuable genetic resource for investigating domestication mechanisms and genome-based breeding of kiwifruit.
文摘The methylation of lysine 4 of histone H3(H3K4),catalyzed by the histone methyltransferase KMT2/SET1,has been functionally identified in many pathogenic fungi but remains unexplored in nematode-trapping fungi(NTFs).Here,we report a regulatory mechanism of an H3K4-specific SET1 orthologue,AoSET1,in the typical nematode-trapping fungus Arthrobotrys oligospora.When the fungus is induced by the nematode,the expression of AoSET1 is up-regulated.Disruption of AoSet1 led to the abolishment of H3K4me.Consequently,the yield of traps and conidia ofΔAoSet1 was significantly lower than that of the WT strain,and the growth rate and pathogenicity were also compromised.Moreover,H3K4 trimethylation was enriched mainly in the promoter of two bZip transcription factor genes(AobZip129 and AobZip350)and ultimately up-regulated the expression level of these two transcription factor genes.In theΔAoSet1 and AoH3K4A strains,the H3^(K4)me modification level was significantly decreased at the promoter of transcription factor genes AobZip129 and AobZip350.These results suggest that AoSET1-mediated H3KEme serves as an epigenetic marker of the promoter region of the targeted transcription factor genes.Furthermore,we found that AobZip129 negatively regulates the formation of adhesive networks and the pathogenicity of downstream AoPABP1 and AoCPR1.Our findings confirm that the epigenetic regulatory mechanism plays a pivotal role in regulating trap formation and pathogenesis in NTFs,and provide novel insights into the mechanisms of interaction between NTFs and nematodes.
基金This work was funded by the National Science Foundation of China(No 32102567 and 31972529)the Program for Shaanxi Science&Technology(2022KJXX-13).
文摘Intensive selective breeding for high growth rate and body weight cause excess abdominal fat in broilers.Gut microbiota and folic acid were reported to regulate lipid metabolism.A total of 210 one-day-old broilers were divided into the control(folic acid at 1.3 mg/kg)and folic acid groups(folic acid at 13 mg/kg)to illustrate the effects of folic acid on growth performance,abdominal fat deposition,and gut microbiota,and the experiment lasted 28 d.Results revealed that dietary folic acid addition decreased abdominal fat percentage(P<0.05)and down-regulated genes expression related to cell proliferation and differentiation in abdominal fat including IGF1,EGF,C/EBPα,PPARγ,PLIN1,FABP4 and PCNA(P<0.05).Folic acid addition decreased caecal Firmicutes-to-Bacteroidetes ratio(P<0.01)and increased the proportions of Alistipes,Oscillospira,Ruminococcus,Clostridium,Dehalobacterium and Parabacteroides(P<0.05).Caecal acetic acid,and propionic acid contents were found to be higher under folic acid treatment(P<0.05),which were negatively related to genes expression associated with adipocyte proliferation and differentiation(P<0.05).Ruminococcus was positively correlated with caecal acetic acid content,and the same phenomenon was detected between propionic acid and Oscillospira and Ruminococcus(P<0.05).Acetic acid and Oscillospira were identified to be negatively associated with abdominal fat percentage(P<0.05).In conclusion,our data demonstrated that dietary supplementation of folic acid reduced fat deposition in broilers by inhibiting abdominal adipocyte proliferation and differentiation,which might be mediated by changes in gut microbiota and short chain fatty acid production.
基金This work was supported by the National Key R&D Program(No.2004BA721A01Z73)the National Key Research and Development Project of China(No.2017YFC1703506).
文摘Pediatric cough is a heterogeneous condition in terms of symptoms and the underlying disease mechanisms.Symptom phenotypes hold complicated interactions between each other to form an intricate network structure.This study aims to investigate whether the network structure of pediatric cough symptoms is associated with the prognosis and outcome of patients.A total of 384 cases were derived from the electronic medical records of a highly experienced traditional Chinese medicine (TCM) physician.The data were divided into two groups according to the therapeutic effect,namely,an invalid group (group A with 40 cases of poor efficacy) and a valid group (group B with 344 cases of good efficacy).Several well-established analysis methods,namely,statistical test,correlation analysis,and complex network analysis,were used to analyze the data.This study reports that symptom networks of patients with pediatric cough are related to the effectiveness of treatment: a dense network of symptoms is associated with great difficulty in treatment.Interventions with the most different symptoms in the symptom network may have improved therapeutic effects.