The 3CL protease, a highly conserved enzyme in the coronavirus, plays a crucial role in the viral life cycle by facilitating viral replication through precise cleavage of polyproteins. Beyond its proteolytic function,...The 3CL protease, a highly conserved enzyme in the coronavirus, plays a crucial role in the viral life cycle by facilitating viral replication through precise cleavage of polyproteins. Beyond its proteolytic function, the 3CL protease also engages in intricate interactions with host cell proteins involved in critical cellular processes such as transcription, translation, and nuclear-cytoplasmic transport, effectively hijacking cellular machinery to promote viral replication. Additionally, it disrupts innate immune signaling pathways, suppresses interferon activity and cleaves antiviral proteins. Furthermore, it modulates host cell death pathways including pyroptosis and apoptosis, interferes with autophagy and inhibits stress granule formation to maintain viral infection and exacerbate viral pathogenesis. This review highlights the molecular mechanisms by which the 3CL protease orchestrates virus-host interactions, emphasizing its central role in coronavirus pathogenesis and highlighting potential therapeutic targets for future interventions.展开更多
In the context of the prevalent winter air quality issues in China marked by declining PM_(2.5)and rising O_(3),this study employed amodified WRF-Chem model to examine the aerosol radiation interaction(ARI),heterogene...In the context of the prevalent winter air quality issues in China marked by declining PM_(2.5)and rising O_(3),this study employed amodified WRF-Chem model to examine the aerosol radiation interaction(ARI),heterogeneous chemistry(AHC),and their combined impact(ALL)on the variations in O_(3)and PM_(2.5)during the 2014–2020 in eastern China.Our analysis confirmed that ARI curtailed O_(3)while elevating PM_(2.5).AHC reduced O_(3)through heterogeneous absorption of NOx and hydroxideswhile notably fostering fine-grained sulfate,resulting in a PM_(2.5)increase.Emission reductions mitigated the inhibitory impact of ARI on meteorological fields and photolysis rates.Emission reduction individually without aerosol feedback led to a 5.43 ppb O_(3)increase and a 22.89μg/m^(3)PM_(2.5)decrease.ARI and AHC amplified the emission-reduction-induced(ERI)O_(3)rise by 1.83 and 0.31 ppb,respectively.The response of ARI to emission diminution brought about a modest PM_(2.5)increase of 0.31μg/m^(3).Conversely,AHC,acting as the primary contributor,caused a noteworthy PM_(2.5)decrease of 4.60μg/m^(3).As efforts concentrate on reducing PM_(2.5),the promotion of ARI on PM_(2.5)counterbalanced the efficacy of emission reduction and the AHC-induced strengthening of PM_(2.5)decrease.The ALL magnified the ERI O_(3)increase by 38.9%and PM_(2.5)decrease by 18.7%.Sensitivity experiments with different degrees of emission reduction demonstrated a consistent linear relationship between the ALL-induced enhancement of O_(3)increase and PM_(2.5)decrease to the ERI PM_(2.5)decline.Our investigation revealed the complex connection between emissions and aerosol feedback in influencing air quality.展开更多
The study of ligand-receptor interactions is of great significance in food flavor perception.In this study,a computer simulation method was used to investigate the mechanism of interaction between umami peptides and T...The study of ligand-receptor interactions is of great significance in food flavor perception.In this study,a computer simulation method was used to investigate the mechanism of interaction between umami peptides and T1R1/T1R3-Venus-flytrap domain(VFT)receptor.The binding site,conformational changes,and binding free energy between umami peptides and T1R1/T1R3-VFT were analyzed through molecular modeling,molecular docking,and molecular dynamics simulations.The receptor model constructed using AlphaFold2 has the best rationality.The molecular docking results showed that umami peptides primarily bound to T1R1-VFT through hydrogen bonding,with key binding residues such as Thr149,Arg151,and Asp108.The binding of umami peptides led to a more stable complex system,and the positively charged amino acids contributed positively to the overall binding free energy.This study provides theoretical support for the development of a better understanding of the interaction between umami substances and the umami receptor.展开更多
Herein,an oxygen-doped porous g-C_(3)N_(4)photocatalyst modified with atomically dispersed Fe(Fe_(1)/OPCN)issuccessfully prepared and exhibits significant superiority in removing refractory sulfonic azo contaminants f...Herein,an oxygen-doped porous g-C_(3)N_(4)photocatalyst modified with atomically dispersed Fe(Fe_(1)/OPCN)issuccessfully prepared and exhibits significant superiority in removing refractory sulfonic azo contaminants fromwater via catalyst-contaminant interaction.The elimination performance of Fe_(1)/OPCN towards acid red 9,acidred 13 and amaranth containing similar azonaphthalene structure and increasing sulfonic acid groups increasesgradually.The amaranth degradation rate of Fe_(1)/OPCN is 17.7 and 6.1 times as that of homogeneous Fenton andOPCN,respectively.In addition,Fe_(1)/OPCN also has more outstanding removal activities towards other con-taminantswith sulfonic acid and azo groups alone.The considerable enhancement for removing sulfonic azocontaminants of Fe_(1)/OPCN is mainly ascribed to the following aspects:(1)The modified Fe could enhance theadsorption towards sulfonic azo compounds to accelerate the mass transfer,act as e^(-)acceptor to promoteinterfacial charge separation,and trigger the self-Fenton reaction to convert in-situ generated H_(2)O_(2)into·OH.(2)Fe(Ⅲ)could coordinate with-N=N-to form d-πconjugation,which could attract e^(-)transfer to attack-N=N-bond.Meanwhile,the inhibited charge recombination could release more free h^(þ)to oxidize sulfonicacid groups into SO4^(-)·.(3)Under the cooperation of abundant multiple active species(·O_(2)^(-),h^(þ),e^(-),·OH,SO4^(-)·)formed during the degradation reaction,sulfonic azo compounds could be completely mineralized into harmlesssmall molecules(CO_(2),H_(2)O,etc.)by means of-N=N-cleavage,hydroxyl substitution,and aromatic ringopening.This work offers a novel approach for effectively eliminating refractory sulfonic azo compounds fromwastewater.展开更多
As the“fourth messenger”of epigenetic regulation,metabolites playa spatiotemporally specific regulatory role in kidney regeneration by dynamically reshaping the state of chromatin modifications.This review systemati...As the“fourth messenger”of epigenetic regulation,metabolites playa spatiotemporally specific regulatory role in kidney regeneration by dynamically reshaping the state of chromatin modifications.This review systematically expounds the coordinated mechanism of the dual axes of succinate/H3K9ac andα-ketoglutarate(α-KG)/TET enzymes:Succinate activates regeneration-related genes by regulating histone acetylation(H3K9ac),whileα-KG relieves the epigenetic repression of the Wnt pathway through TET-mediated DNA demethylation.The dynamic balance between the two maintains epigenetic plasticity.Multi-omics integration strategies(such as Gaussian graphical models and deep learning frameworks)and single-cell epigenetic tracking technologies(such as spatial metabolomics)have revealed the regulation of metabolite gradients on cellular heterogeneity and the immune microenvironment.The coordinated application of metabolite precursor supplementation(such as NAD precursors)and dynamic monitoring systems(such as isotope tracing and artifi cial intelligence models)has promoted the shift of metabolic medicine from the“static replacement”paradigm to the“dynamic reshaping”paradigm.However,technical bottlenecks(such as insuffi cient multimodal integration)and clinical translation pitfalls(such as challenges in standardized production)still need to be overcome.In the future,through the development of“metabolism-immunity”co-regulatory strategies and intelligent closed-loop systems,it is expected to achieve precise interventions for kidney regeneration and disease treatment.展开更多
Perovskite oxides have been widely applied as an effective catalyst in heterogeneous catalysis.However,the rational design of active catalysts has been restricted by the lack of understanding of the electronic structu...Perovskite oxides have been widely applied as an effective catalyst in heterogeneous catalysis.However,the rational design of active catalysts has been restricted by the lack of understanding of the electronic structure.The correlations between surface properties and bulk electronic structure have been ignored.Herein,a simple handler of LaFeO_(3)with diluted HNO3 was employed to tune the electronic structure and catalytic properties.Experimental analysis and theoretical calculations elucidate that acid etching could raise the Fe valence and enhance Fe-O covalency in the octahedral structure,thereby lessening charge transfer energy.Enhanced Fe-O covalency could lower oxygen vacancy formation energy and enhance oxygen mobility.In-situ DRIFTS results indicated the inherent adsorption capability of Toluene and CO molecules has been greatly improved owing to higher Fe-O covalency.As compared,the catalysts after acid etching exhibited higher catalytic activity,and the T_(90)had a great reduction of 45 and 58℃ for toluene and CO oxidation,respectively.A deeper understanding of electronic structure in perovskite oxides may inspire the design of high-performance catalysts.展开更多
Alkaline earth-metal titanates ATiO_(3)(A=Ca,Sr,and Ba)with a perovskite-type structure were used as supports for Ru-based catalysts to produce CO_(x)-free H_(2)via NH_(3)decomposition.The effects of alkalineearth met...Alkaline earth-metal titanates ATiO_(3)(A=Ca,Sr,and Ba)with a perovskite-type structure were used as supports for Ru-based catalysts to produce CO_(x)-free H_(2)via NH_(3)decomposition.The effects of alkalineearth metals on the physicochemical characteristics and catalytic activities of Ru/ATiO_(3)for NH_(3)decomposition were investigated using various techniques.The order of Ru/ATiO_(3)for NH_(3)conversion is Ru/BaTiO_(3)>Ru/SrTiO_(3)>Ru/CaTiO_(3)>Ru/TiO_(2)at the identical conditions,with the Ru/BaTiO_(3)catalyst demonstrating the highest NH_(3)conversion of 77.8%at 450℃and a gas hourly space velocity of 30,000 mL/gcat/h,which is 8.7,2.1,and 1.3 times of that over Ru/TiO_(2),Ru/CaTiO_(3),and Ru/SrTiO_(3),respectively.The formation of the ATiO_(3)phase can enrich the concentration of basic sites and oxygen vacancies compared with TiO_(2),which can induce the presence of strong metal-support interaction(SMSI)through the formation of Ru-O-Ti bonds.This SMSI effect increased the dispersion and electron density of Ru nano-particles on ATiO_(3)supports,and the electron-rich Ru nano-particles could weaken the chemisorptive strength of N_(2)and H_(2)on the Ru/ATiO_(3)catalysts,thereby promoting the reaction rate for NH_(3)decomposition.展开更多
A three-dimensional numerical model of sand wave dynamics,incorporating the interaction of currents and waves at various angles,has been developed using the Regional Ocean Modeling System(ROMS).This model accounts for...A three-dimensional numerical model of sand wave dynamics,incorporating the interaction of currents and waves at various angles,has been developed using the Regional Ocean Modeling System(ROMS).This model accounts for both bedload and suspended load sediment transport under combined waves and current conditions.The investigation examines the influence of several key parameters,including the rotation angle of sand waves relative to the main current,tidal current velocity amplitude,residual current,water depth,wave height,wave period,and wave direction,on sand wave evolution.The growth rate and migration rate of sand waves decrease as their rotation angle increases.For rotation angles smaller than 15°,sand wave evolution can be effectively simulated by a vertical 2D model with an error within 10%.The numerical results demonstrate that variations in tidal current velocity amplitude or residual current affect both vertical growth and horizontal migration of sand waves.As tidal current velocity amplitude and residual current increase,the growth rate initially rises to a maximum before decreasing.The migration rate shows a consistent increase with increasing tidal current amplitude and residual current.Under combined waves and current,both growth and migration rates decrease as water depth increases.With increasing wave height and period,the growth rate and migration rate initially rise to maximum values before declining,while showing a consistent increase with wave height and period.The change rate of sand waves reaches its maximum when wave propagation aligns parallel to tidal currents,and reaches its minimum when wave propagation is perpendicular to the currents.This phenomenon can be explained by the fluctuation of total bed shear stress relative to the angle of interaction between waves and current.展开更多
Rock discontinuities control rock mechanical behaviors and significantly influence the stability of rock masses.However,existing discontinuity mapping algorithms are susceptible to noise,and the calculation results ca...Rock discontinuities control rock mechanical behaviors and significantly influence the stability of rock masses.However,existing discontinuity mapping algorithms are susceptible to noise,and the calculation results cannot be fed back to users timely.To address this issue,we proposed a human-machine interaction(HMI)method for discontinuity mapping.Users can help the algorithm identify the noise and make real-time result judgments and parameter adjustments.For this,a regular cube was selected to illustrate the workflows:(1)point cloud was acquired using remote sensing;(2)the HMI method was employed to select reference points and angle thresholds to detect group discontinuity;(3)individual discontinuities were extracted from the group discontinuity using a density-based cluster algorithm;and(4)the orientation of each discontinuity was measured based on a plane fitting algorithm.The method was applied to a well-studied highway road cut and a complex natural slope.The consistency of the computational results with field measurements demonstrates its good accuracy,and the average error in the dip direction and dip angle for both cases was less than 3.Finally,the computational time of the proposed method was compared with two other popular algorithms,and the reduction in computational time by tens of times proves its high computational efficiency.This method provides geologists and geological engineers with a new idea to map rapidly and accurately rock structures under large amounts of noises or unclear features.展开更多
A novel Cu-t-ZrO_(2)catalyst with enhanced electronic metal-support interaction(EMSI)is designed for efficient electrocatalytic conversion of nitrate(NO_(3^(-)))to ammonia(NH_(3)),achieving a remarkable Faradaic effic...A novel Cu-t-ZrO_(2)catalyst with enhanced electronic metal-support interaction(EMSI)is designed for efficient electrocatalytic conversion of nitrate(NO_(3^(-)))to ammonia(NH_(3)),achieving a remarkable Faradaic efficiency and yield rate of 97.54%and 33.64 mg h^(-1)mg_(cat)^(-1),respectively.Electrons are more likely to be transferred from Cu to t-ZrO_(2)at the electron-rich interface due to the lower work function,which promotes the formation of highly active Cu species and facilitates NO_(3^(-))adsorption,ensuring selective conversion into NH_(3).展开更多
The electron localization is considered as a promising approach to optimize electromagnetic waves(EMW)dissipation.However,it is still difficult to realize well-controlled electron localization and elucidate the relate...The electron localization is considered as a promising approach to optimize electromagnetic waves(EMW)dissipation.However,it is still difficult to realize well-controlled electron localization and elucidate the related EMW loss mechanisms for current researches.In this study,a novel two-dimensional MXene(Ti_(3)C_(2)T_(x))nanosheet decorated with Ni nanoclusters(Ni-NC)system to construct an effective electron localization model based on electronic orbital structure is explored.Theoretical simulations and experimental results reveal that the metal-support interaction between Ni-NC and MXene disrupts symmetric electronic environments,leading to enhanced electron localization and dipole polarization.Additionally,Ni-NC generate a strong interfacial electric field,strengthening heterointerface interactions and promoting interfacial polarization.As a result,the optimized material achieves an exceptional reflection loss(RLmin)of-54 dB and a broad effective absorption bandwidth of 6.8 GHz.This study offers critical insights into the in-depth relationship between electron localization and EMW dissipation,providing a pathway for electron localization engineering in functional materials such as semiconductors,spintronics,and catalysis.展开更多
In this paper,we mainly focus on proving the existence of lump solutions to a generalized(3+1)-dimensional nonlinear differential equation.Hirota’s bilinear method and a quadratic function method are employed to deri...In this paper,we mainly focus on proving the existence of lump solutions to a generalized(3+1)-dimensional nonlinear differential equation.Hirota’s bilinear method and a quadratic function method are employed to derive the lump solutions localized in the whole plane for a(3+1)-dimensional nonlinear differential equation.Three examples of such a nonlinear equation are presented to investigate the exact expressions of the lump solutions.Moreover,the 3d plots and corresponding density plots of the solutions are given to show the space structures of the lump waves.In addition,the breath-wave solutions and several interaction solutions of the(3+1)-dimensional nonlinear differential equation are obtained and their dynamics are analyzed.展开更多
In order to explore the effect mechanism of solvent on the synthesis of the metal organic framework materials, the microscopic interaction between solvent and framework and the effects of N,N-dimethyl-formamide(DMF) o...In order to explore the effect mechanism of solvent on the synthesis of the metal organic framework materials, the microscopic interaction between solvent and framework and the effects of N,N-dimethyl-formamide(DMF) or N-methyl- 2-pyrrolidone(NMP) on solvothermal synthesis of [Zn4O(BDC)3]8 were investigated through a combined DFT and experimental study. XRD and SEM showed that the absorbability of NMP in the pore of [Zn4O(BDC)3]8 was weaker than that of DMF. The thermal decomposition temperature of [Zn4O(BDC)3]8 synthesized in DMF was higher than that in NMP according to TG and FT-IR. In addition, the nitrogen sorption isotherms indicated that NMP improved gas sorption property of [Zn4O(BDC)3]8. The COSMO optimized calculations indicated that the total energy of Zn4O(BDC)3 in NMP was higher than that in DMF, and compared with non-solvent system, the charge of zinc atoms decreased and the charge value was the smallest in NMP. Furthermore, the interaction of DMF, NMP or DEF in [Zn4O(BDC)3]8 crystal model was calculated by DFT method. The results suggested that NMP should be easier to be removed from pore of materials than DMF from the point of view of energy state. It can be concluded that NMP was a favorable solvent to synthesize [Zn4O(BDC)3]8 and the microscopic mechanism was that the binding force between Zn4O(BDC)3 and NMP molecule was weaker than DMF.展开更多
A γ-TiAl alloy with nominal composition of Ti-47%Al（molar fraction） was directionally solidified in an alumina mould with an Y2O3 protective coating.The effects of processing parameters（melting temperature and int...A γ-TiAl alloy with nominal composition of Ti-47%Al（molar fraction） was directionally solidified in an alumina mould with an Y2O3 protective coating.The effects of processing parameters（melting temperature and interaction time） on the metal-coating interface,microstructure and chemical composition of the alloy were evaluated.The result shows that the Y2O3 protective coating exhibits an effective barrier capability to avoid direct contact between the mould base material and the TiAl melt,although the Y2O3 coating is found to suffer some erosion and be slightly dissolved by the molten TiAl due to the coating-metal interactions.The directionally solidified alloys were contaminated with Y and O,and Y2O3 inclusions were dispersed in the metal matrix.The reason for this metal contamination is the Y2O3 coating dissolution by the TiAl melt.One mode of the interaction between Y2O3 and the TiAl melt is dissolution of yttrium and atomic oxygen in the melt by reaction Y2O3（s）=2Y（in TiAl melt）＋3O（in TiAl melt）.Both the extent of alloy contamination and the volume fractions of Y2O3 inclusions depend on the melting temperature and the interaction time.展开更多
AIM: To investigate the biological function of 14-3-3σ protein and to look for proteins that interact with 14-3-3σ protein in colon cancer stem cells. METHODS: Reverse transcription polymerase chain reaction was per...AIM: To investigate the biological function of 14-3-3σ protein and to look for proteins that interact with 14-3-3σ protein in colon cancer stem cells. METHODS: Reverse transcription polymerase chain reaction was performed to amplify the 14-3-3σ gene from the mRNA of colon cancer stem cells. The gene was then cloned into the pGEM-T vector. After being sequenced, the target gene 14-3-3σ was cut from the pGEM-T vector and cloned into the pGBKT7 yeast expression plasmid. Then, the bait plasmid pGBKT7-14-3-3σ was transformed into the yeast strain AH109. After the expression of the pGBKT7-14-3-3σ fusion protein in the AH109 yeast strain was accomplished, a yeast two-hybrid screening assay was performed by mating AH109 with Y187 that contained a HeLa cDNA library plasmid. The interaction between the 14-3-3σ protein and the proteins obtained from positive colonies was further confirmed by repeating the yeast two-hybridscreen. After extracting and sequencing the plasmids from the positive colonies, we performed a bioinformatics analysis. A coimmunoprecipitation assay was performed to confirm the interaction between 14-3-3σ and the proteins obtained from the positive colonies. Finally, we constructed 14-3-3σ and potassium channel modulatory factor 1 (KCMF1) siRNA expression plasmids and transfected them into colon cancer stem cells. RESULTS: The bait plasmid pGBKT7-14-3-3σ was constructed successfully, and the 14-3-3σ protein had no toxic or autonomous activation effect on the yeast. Nineteen true-positive colonies were selected and sequenced, and their full-length sequences were obtained. We searched for homologous DNA sequences for these sequences from GenBank. Among the positive colonies, four coding genes with known functions were obtained, including KCMF1 , quinone oxidore-ductase (NQO2 ), hydroxyisobutyrate dehydrogenase (HIBADH ) and 14-3-3σ . For the subsequent coimmu-noprecipitation assay, the plasmids PCDEF-Flag-14-3-3σ, PCDEF-Myc-KCMF1, PCDEF-Myc-NQO2 and PCDEF-Myc-HIBADH were successfully constructed, and the sequences were further confirmed by DNA sequencing. The Fugene 6 reagent was used to transfect the plasmids, and fluorescence-activated cell sorting analysis showed the transfection efficiency was 97.8% after 48 h. The HEK 293FT cells showed the stable expression of the PCDEF-Flag-14-3-3σ, PCDEF-Myc-KCMF1, PCDEF-Myc-NQO2 and PCDEF-Myc-HIBADH plasmids. After anti-Myc antibody immunoprecipitation with Myc-KCMF1, Myc-NQO2 and Myc-HIBADH from cell lysates, the presence of Flag-14-3-3σ protein in the immuno-precipitated complex was determined by western blot analysis. The knock-down expression of the 14-3-3σ and KCMF1 proteins significantly inhibited cell proliferation and colony formation of SW1116csc. CONCLUSION: Genes of the proteins that interactedwith 14-3-3σ were successfully screened from a HeLa cDNA library. KCMF1 and 14-3-3σ protein may affect the proliferation and colony formation of human colon cancer stem cells.展开更多
Transference of CuO species and thermal solid-solid interaction in CuO/CeO2-Al2O3 catalyst prepared by an impregnation method were characterized by in-situ XRD, Raman spectroscopy and H2-TPR techniques. For the cataly...Transference of CuO species and thermal solid-solid interaction in CuO/CeO2-Al2O3 catalyst prepared by an impregnation method were characterized by in-situ XRD, Raman spectroscopy and H2-TPR techniques. For the catalyst calcined at 300℃, two kinds of CuO species coexist on the surface, that is, highly dispersed and bulk CuO crystalline phase. Four kinds of CuO species are present for the catalyst calcined at 600 ℃, ： （1） highly dispersed CuO, （2） bulk CuO on the surface, （3） bulk CuO in the internal layer of CeO2, and （4） CuAl2O4 formed from CuO-Al2O3 interaction. For the catalyst calcined at 800 ℃,C, besides very little highly dispersed and bulk CuO on the surface, most of the CuO has transferred into the internal layer of CeO2 and the mass of CuAl2O4 are increased. At 900 ℃,, all of CuO has diffused into the internal layer of CeO2 and formed CuAl2O4. The results show that the distribution of CuO species in the catalysts depends on the calcination temperature; the different CuO species can be effectively confirmed by in-situ XRD, Raman spectroscopy and H2-TPR techniques.展开更多
基金supported by the National Natural Science Foundation of China(grant no.82370015).
文摘The 3CL protease, a highly conserved enzyme in the coronavirus, plays a crucial role in the viral life cycle by facilitating viral replication through precise cleavage of polyproteins. Beyond its proteolytic function, the 3CL protease also engages in intricate interactions with host cell proteins involved in critical cellular processes such as transcription, translation, and nuclear-cytoplasmic transport, effectively hijacking cellular machinery to promote viral replication. Additionally, it disrupts innate immune signaling pathways, suppresses interferon activity and cleaves antiviral proteins. Furthermore, it modulates host cell death pathways including pyroptosis and apoptosis, interferes with autophagy and inhibits stress granule formation to maintain viral infection and exacerbate viral pathogenesis. This review highlights the molecular mechanisms by which the 3CL protease orchestrates virus-host interactions, emphasizing its central role in coronavirus pathogenesis and highlighting potential therapeutic targets for future interventions.
基金supported by the National Natural Science Foundation of China(No.42077192)the National Key Basic Research&Development Program of China(No.2020YFA0607802).
文摘In the context of the prevalent winter air quality issues in China marked by declining PM_(2.5)and rising O_(3),this study employed amodified WRF-Chem model to examine the aerosol radiation interaction(ARI),heterogeneous chemistry(AHC),and their combined impact(ALL)on the variations in O_(3)and PM_(2.5)during the 2014–2020 in eastern China.Our analysis confirmed that ARI curtailed O_(3)while elevating PM_(2.5).AHC reduced O_(3)through heterogeneous absorption of NOx and hydroxideswhile notably fostering fine-grained sulfate,resulting in a PM_(2.5)increase.Emission reductions mitigated the inhibitory impact of ARI on meteorological fields and photolysis rates.Emission reduction individually without aerosol feedback led to a 5.43 ppb O_(3)increase and a 22.89μg/m^(3)PM_(2.5)decrease.ARI and AHC amplified the emission-reduction-induced(ERI)O_(3)rise by 1.83 and 0.31 ppb,respectively.The response of ARI to emission diminution brought about a modest PM_(2.5)increase of 0.31μg/m^(3).Conversely,AHC,acting as the primary contributor,caused a noteworthy PM_(2.5)decrease of 4.60μg/m^(3).As efforts concentrate on reducing PM_(2.5),the promotion of ARI on PM_(2.5)counterbalanced the efficacy of emission reduction and the AHC-induced strengthening of PM_(2.5)decrease.The ALL magnified the ERI O_(3)increase by 38.9%and PM_(2.5)decrease by 18.7%.Sensitivity experiments with different degrees of emission reduction demonstrated a consistent linear relationship between the ALL-induced enhancement of O_(3)increase and PM_(2.5)decrease to the ERI PM_(2.5)decline.Our investigation revealed the complex connection between emissions and aerosol feedback in influencing air quality.
基金funded by the National Natural Science Foundation of China(32001824,31972198)supported by the Startup Fund for Young Faculty at SJTU(Shanghai Jiao Tong University)High Level Innovation Team and Distinguished Scholar Project of Guangxi Universities and Colleges(2020[6]).
文摘The study of ligand-receptor interactions is of great significance in food flavor perception.In this study,a computer simulation method was used to investigate the mechanism of interaction between umami peptides and T1R1/T1R3-Venus-flytrap domain(VFT)receptor.The binding site,conformational changes,and binding free energy between umami peptides and T1R1/T1R3-VFT were analyzed through molecular modeling,molecular docking,and molecular dynamics simulations.The receptor model constructed using AlphaFold2 has the best rationality.The molecular docking results showed that umami peptides primarily bound to T1R1-VFT through hydrogen bonding,with key binding residues such as Thr149,Arg151,and Asp108.The binding of umami peptides led to a more stable complex system,and the positively charged amino acids contributed positively to the overall binding free energy.This study provides theoretical support for the development of a better understanding of the interaction between umami substances and the umami receptor.
基金supported by the Natural Science Foundation of Jiangsu Province(BK20221541)National Natural Science Foundation of China(21707052)Jiangsu Agriculture Science and Technology Innovation Fund(CX(20)3108).
文摘Herein,an oxygen-doped porous g-C_(3)N_(4)photocatalyst modified with atomically dispersed Fe(Fe_(1)/OPCN)issuccessfully prepared and exhibits significant superiority in removing refractory sulfonic azo contaminants fromwater via catalyst-contaminant interaction.The elimination performance of Fe_(1)/OPCN towards acid red 9,acidred 13 and amaranth containing similar azonaphthalene structure and increasing sulfonic acid groups increasesgradually.The amaranth degradation rate of Fe_(1)/OPCN is 17.7 and 6.1 times as that of homogeneous Fenton andOPCN,respectively.In addition,Fe_(1)/OPCN also has more outstanding removal activities towards other con-taminantswith sulfonic acid and azo groups alone.The considerable enhancement for removing sulfonic azocontaminants of Fe_(1)/OPCN is mainly ascribed to the following aspects:(1)The modified Fe could enhance theadsorption towards sulfonic azo compounds to accelerate the mass transfer,act as e^(-)acceptor to promoteinterfacial charge separation,and trigger the self-Fenton reaction to convert in-situ generated H_(2)O_(2)into·OH.(2)Fe(Ⅲ)could coordinate with-N=N-to form d-πconjugation,which could attract e^(-)transfer to attack-N=N-bond.Meanwhile,the inhibited charge recombination could release more free h^(þ)to oxidize sulfonicacid groups into SO4^(-)·.(3)Under the cooperation of abundant multiple active species(·O_(2)^(-),h^(þ),e^(-),·OH,SO4^(-)·)formed during the degradation reaction,sulfonic azo compounds could be completely mineralized into harmlesssmall molecules(CO_(2),H_(2)O,etc.)by means of-N=N-cleavage,hydroxyl substitution,and aromatic ringopening.This work offers a novel approach for effectively eliminating refractory sulfonic azo compounds fromwastewater.
基金funded by Medical Science Research Project of Hebei(No.20220364).
文摘As the“fourth messenger”of epigenetic regulation,metabolites playa spatiotemporally specific regulatory role in kidney regeneration by dynamically reshaping the state of chromatin modifications.This review systematically expounds the coordinated mechanism of the dual axes of succinate/H3K9ac andα-ketoglutarate(α-KG)/TET enzymes:Succinate activates regeneration-related genes by regulating histone acetylation(H3K9ac),whileα-KG relieves the epigenetic repression of the Wnt pathway through TET-mediated DNA demethylation.The dynamic balance between the two maintains epigenetic plasticity.Multi-omics integration strategies(such as Gaussian graphical models and deep learning frameworks)and single-cell epigenetic tracking technologies(such as spatial metabolomics)have revealed the regulation of metabolite gradients on cellular heterogeneity and the immune microenvironment.The coordinated application of metabolite precursor supplementation(such as NAD precursors)and dynamic monitoring systems(such as isotope tracing and artifi cial intelligence models)has promoted the shift of metabolic medicine from the“static replacement”paradigm to the“dynamic reshaping”paradigm.However,technical bottlenecks(such as insuffi cient multimodal integration)and clinical translation pitfalls(such as challenges in standardized production)still need to be overcome.In the future,through the development of“metabolism-immunity”co-regulatory strategies and intelligent closed-loop systems,it is expected to achieve precise interventions for kidney regeneration and disease treatment.
基金the National Natural Science Foundation of China(Nos.22376178,22322606,22276105)the National Key Research and Development Program of China(No.2022YFC3704300)the Beijing Natural Science Foundation(No.8222054).
文摘Perovskite oxides have been widely applied as an effective catalyst in heterogeneous catalysis.However,the rational design of active catalysts has been restricted by the lack of understanding of the electronic structure.The correlations between surface properties and bulk electronic structure have been ignored.Herein,a simple handler of LaFeO_(3)with diluted HNO3 was employed to tune the electronic structure and catalytic properties.Experimental analysis and theoretical calculations elucidate that acid etching could raise the Fe valence and enhance Fe-O covalency in the octahedral structure,thereby lessening charge transfer energy.Enhanced Fe-O covalency could lower oxygen vacancy formation energy and enhance oxygen mobility.In-situ DRIFTS results indicated the inherent adsorption capability of Toluene and CO molecules has been greatly improved owing to higher Fe-O covalency.As compared,the catalysts after acid etching exhibited higher catalytic activity,and the T_(90)had a great reduction of 45 and 58℃ for toluene and CO oxidation,respectively.A deeper understanding of electronic structure in perovskite oxides may inspire the design of high-performance catalysts.
基金financially supported by the National Natural Science Foundation of China(21968028)the Xinjiang Tianchi Talent Project(CZ002732)。
文摘Alkaline earth-metal titanates ATiO_(3)(A=Ca,Sr,and Ba)with a perovskite-type structure were used as supports for Ru-based catalysts to produce CO_(x)-free H_(2)via NH_(3)decomposition.The effects of alkalineearth metals on the physicochemical characteristics and catalytic activities of Ru/ATiO_(3)for NH_(3)decomposition were investigated using various techniques.The order of Ru/ATiO_(3)for NH_(3)conversion is Ru/BaTiO_(3)>Ru/SrTiO_(3)>Ru/CaTiO_(3)>Ru/TiO_(2)at the identical conditions,with the Ru/BaTiO_(3)catalyst demonstrating the highest NH_(3)conversion of 77.8%at 450℃and a gas hourly space velocity of 30,000 mL/gcat/h,which is 8.7,2.1,and 1.3 times of that over Ru/TiO_(2),Ru/CaTiO_(3),and Ru/SrTiO_(3),respectively.The formation of the ATiO_(3)phase can enrich the concentration of basic sites and oxygen vacancies compared with TiO_(2),which can induce the presence of strong metal-support interaction(SMSI)through the formation of Ru-O-Ti bonds.This SMSI effect increased the dispersion and electron density of Ru nano-particles on ATiO_(3)supports,and the electron-rich Ru nano-particles could weaken the chemisorptive strength of N_(2)and H_(2)on the Ru/ATiO_(3)catalysts,thereby promoting the reaction rate for NH_(3)decomposition.
基金the National Natural Science Foundation of China(Grant Nos.52371289 and 51979192).
文摘A three-dimensional numerical model of sand wave dynamics,incorporating the interaction of currents and waves at various angles,has been developed using the Regional Ocean Modeling System(ROMS).This model accounts for both bedload and suspended load sediment transport under combined waves and current conditions.The investigation examines the influence of several key parameters,including the rotation angle of sand waves relative to the main current,tidal current velocity amplitude,residual current,water depth,wave height,wave period,and wave direction,on sand wave evolution.The growth rate and migration rate of sand waves decrease as their rotation angle increases.For rotation angles smaller than 15°,sand wave evolution can be effectively simulated by a vertical 2D model with an error within 10%.The numerical results demonstrate that variations in tidal current velocity amplitude or residual current affect both vertical growth and horizontal migration of sand waves.As tidal current velocity amplitude and residual current increase,the growth rate initially rises to a maximum before decreasing.The migration rate shows a consistent increase with increasing tidal current amplitude and residual current.Under combined waves and current,both growth and migration rates decrease as water depth increases.With increasing wave height and period,the growth rate and migration rate initially rise to maximum values before declining,while showing a consistent increase with wave height and period.The change rate of sand waves reaches its maximum when wave propagation aligns parallel to tidal currents,and reaches its minimum when wave propagation is perpendicular to the currents.This phenomenon can be explained by the fluctuation of total bed shear stress relative to the angle of interaction between waves and current.
基金supported by the National Key R&D Program of China(No.2023YFC3081200)the National Natural Science Foundation of China(No.42077264)the Scientific Research Project of PowerChina Huadong Engineering Corporation Limited(HDEC-2022-0301).
文摘Rock discontinuities control rock mechanical behaviors and significantly influence the stability of rock masses.However,existing discontinuity mapping algorithms are susceptible to noise,and the calculation results cannot be fed back to users timely.To address this issue,we proposed a human-machine interaction(HMI)method for discontinuity mapping.Users can help the algorithm identify the noise and make real-time result judgments and parameter adjustments.For this,a regular cube was selected to illustrate the workflows:(1)point cloud was acquired using remote sensing;(2)the HMI method was employed to select reference points and angle thresholds to detect group discontinuity;(3)individual discontinuities were extracted from the group discontinuity using a density-based cluster algorithm;and(4)the orientation of each discontinuity was measured based on a plane fitting algorithm.The method was applied to a well-studied highway road cut and a complex natural slope.The consistency of the computational results with field measurements demonstrates its good accuracy,and the average error in the dip direction and dip angle for both cases was less than 3.Finally,the computational time of the proposed method was compared with two other popular algorithms,and the reduction in computational time by tens of times proves its high computational efficiency.This method provides geologists and geological engineers with a new idea to map rapidly and accurately rock structures under large amounts of noises or unclear features.
基金supported by the Natural Scientific Foundation of China(Nos.22127803,22174110,22203050)Natural Scientific Foundation of Shandong(No.ZR2022QB002)China Postdoctoral Science Foundation(No.2020T130331)。
文摘A novel Cu-t-ZrO_(2)catalyst with enhanced electronic metal-support interaction(EMSI)is designed for efficient electrocatalytic conversion of nitrate(NO_(3^(-)))to ammonia(NH_(3)),achieving a remarkable Faradaic efficiency and yield rate of 97.54%and 33.64 mg h^(-1)mg_(cat)^(-1),respectively.Electrons are more likely to be transferred from Cu to t-ZrO_(2)at the electron-rich interface due to the lower work function,which promotes the formation of highly active Cu species and facilitates NO_(3^(-))adsorption,ensuring selective conversion into NH_(3).
基金supported by the National Key Research and Development Program of China (Grant No. 2024YFE0100600)the National Natural Science Foundation of China (No 52373303)+2 种基金the Shanghai Municipal Science and Technology Major Project (2021SHZDZX0100)the Fundamental Research Funds for the Central Universitiesthe Interdisciplinary Joint Research and Development Project of Tongji University (No 2024-4-ZD-03)
文摘The electron localization is considered as a promising approach to optimize electromagnetic waves(EMW)dissipation.However,it is still difficult to realize well-controlled electron localization and elucidate the related EMW loss mechanisms for current researches.In this study,a novel two-dimensional MXene(Ti_(3)C_(2)T_(x))nanosheet decorated with Ni nanoclusters(Ni-NC)system to construct an effective electron localization model based on electronic orbital structure is explored.Theoretical simulations and experimental results reveal that the metal-support interaction between Ni-NC and MXene disrupts symmetric electronic environments,leading to enhanced electron localization and dipole polarization.Additionally,Ni-NC generate a strong interfacial electric field,strengthening heterointerface interactions and promoting interfacial polarization.As a result,the optimized material achieves an exceptional reflection loss(RLmin)of-54 dB and a broad effective absorption bandwidth of 6.8 GHz.This study offers critical insights into the in-depth relationship between electron localization and EMW dissipation,providing a pathway for electron localization engineering in functional materials such as semiconductors,spintronics,and catalysis.
基金supported by the National Natural Science Foundation of China(Nos.12101572,12371256)2023 Shanxi Province Graduate Innovation Project(No.2023KY614)the 19th Graduate Science and Technology Project of North University of China(No.20231943)。
文摘In this paper,we mainly focus on proving the existence of lump solutions to a generalized(3+1)-dimensional nonlinear differential equation.Hirota’s bilinear method and a quadratic function method are employed to derive the lump solutions localized in the whole plane for a(3+1)-dimensional nonlinear differential equation.Three examples of such a nonlinear equation are presented to investigate the exact expressions of the lump solutions.Moreover,the 3d plots and corresponding density plots of the solutions are given to show the space structures of the lump waves.In addition,the breath-wave solutions and several interaction solutions of the(3+1)-dimensional nonlinear differential equation are obtained and their dynamics are analyzed.
基金Project(51104185)supported by the National Natural Science Foundation of ChinaProject(2010QZZD003)supported by the Key Project of Central South University of Fundamental Research Funds for the Central Universities of China
文摘In order to explore the effect mechanism of solvent on the synthesis of the metal organic framework materials, the microscopic interaction between solvent and framework and the effects of N,N-dimethyl-formamide(DMF) or N-methyl- 2-pyrrolidone(NMP) on solvothermal synthesis of [Zn4O(BDC)3]8 were investigated through a combined DFT and experimental study. XRD and SEM showed that the absorbability of NMP in the pore of [Zn4O(BDC)3]8 was weaker than that of DMF. The thermal decomposition temperature of [Zn4O(BDC)3]8 synthesized in DMF was higher than that in NMP according to TG and FT-IR. In addition, the nitrogen sorption isotherms indicated that NMP improved gas sorption property of [Zn4O(BDC)3]8. The COSMO optimized calculations indicated that the total energy of Zn4O(BDC)3 in NMP was higher than that in DMF, and compared with non-solvent system, the charge of zinc atoms decreased and the charge value was the smallest in NMP. Furthermore, the interaction of DMF, NMP or DEF in [Zn4O(BDC)3]8 crystal model was calculated by DFT method. The results suggested that NMP should be easier to be removed from pore of materials than DMF from the point of view of energy state. It can be concluded that NMP was a favorable solvent to synthesize [Zn4O(BDC)3]8 and the microscopic mechanism was that the binding force between Zn4O(BDC)3 and NMP molecule was weaker than DMF.
文摘A γ-TiAl alloy with nominal composition of Ti-47%Al（molar fraction） was directionally solidified in an alumina mould with an Y2O3 protective coating.The effects of processing parameters（melting temperature and interaction time） on the metal-coating interface,microstructure and chemical composition of the alloy were evaluated.The result shows that the Y2O3 protective coating exhibits an effective barrier capability to avoid direct contact between the mould base material and the TiAl melt,although the Y2O3 coating is found to suffer some erosion and be slightly dissolved by the molten TiAl due to the coating-metal interactions.The directionally solidified alloys were contaminated with Y and O,and Y2O3 inclusions were dispersed in the metal matrix.The reason for this metal contamination is the Y2O3 coating dissolution by the TiAl melt.One mode of the interaction between Y2O3 and the TiAl melt is dissolution of yttrium and atomic oxygen in the melt by reaction Y2O3（s）=2Y（in TiAl melt）＋3O（in TiAl melt）.Both the extent of alloy contamination and the volume fractions of Y2O3 inclusions depend on the melting temperature and the interaction time.
基金Supported by The Medical Guidance Projects of Shanghai Science Committee,No.10411961800National Natural Science Foundation of China,No.81101617
文摘AIM: To investigate the biological function of 14-3-3σ protein and to look for proteins that interact with 14-3-3σ protein in colon cancer stem cells. METHODS: Reverse transcription polymerase chain reaction was performed to amplify the 14-3-3σ gene from the mRNA of colon cancer stem cells. The gene was then cloned into the pGEM-T vector. After being sequenced, the target gene 14-3-3σ was cut from the pGEM-T vector and cloned into the pGBKT7 yeast expression plasmid. Then, the bait plasmid pGBKT7-14-3-3σ was transformed into the yeast strain AH109. After the expression of the pGBKT7-14-3-3σ fusion protein in the AH109 yeast strain was accomplished, a yeast two-hybrid screening assay was performed by mating AH109 with Y187 that contained a HeLa cDNA library plasmid. The interaction between the 14-3-3σ protein and the proteins obtained from positive colonies was further confirmed by repeating the yeast two-hybridscreen. After extracting and sequencing the plasmids from the positive colonies, we performed a bioinformatics analysis. A coimmunoprecipitation assay was performed to confirm the interaction between 14-3-3σ and the proteins obtained from the positive colonies. Finally, we constructed 14-3-3σ and potassium channel modulatory factor 1 (KCMF1) siRNA expression plasmids and transfected them into colon cancer stem cells. RESULTS: The bait plasmid pGBKT7-14-3-3σ was constructed successfully, and the 14-3-3σ protein had no toxic or autonomous activation effect on the yeast. Nineteen true-positive colonies were selected and sequenced, and their full-length sequences were obtained. We searched for homologous DNA sequences for these sequences from GenBank. Among the positive colonies, four coding genes with known functions were obtained, including KCMF1 , quinone oxidore-ductase (NQO2 ), hydroxyisobutyrate dehydrogenase (HIBADH ) and 14-3-3σ . For the subsequent coimmu-noprecipitation assay, the plasmids PCDEF-Flag-14-3-3σ, PCDEF-Myc-KCMF1, PCDEF-Myc-NQO2 and PCDEF-Myc-HIBADH were successfully constructed, and the sequences were further confirmed by DNA sequencing. The Fugene 6 reagent was used to transfect the plasmids, and fluorescence-activated cell sorting analysis showed the transfection efficiency was 97.8% after 48 h. The HEK 293FT cells showed the stable expression of the PCDEF-Flag-14-3-3σ, PCDEF-Myc-KCMF1, PCDEF-Myc-NQO2 and PCDEF-Myc-HIBADH plasmids. After anti-Myc antibody immunoprecipitation with Myc-KCMF1, Myc-NQO2 and Myc-HIBADH from cell lysates, the presence of Flag-14-3-3σ protein in the immuno-precipitated complex was determined by western blot analysis. The knock-down expression of the 14-3-3σ and KCMF1 proteins significantly inhibited cell proliferation and colony formation of SW1116csc. CONCLUSION: Genes of the proteins that interactedwith 14-3-3σ were successfully screened from a HeLa cDNA library. KCMF1 and 14-3-3σ protein may affect the proliferation and colony formation of human colon cancer stem cells.
文摘Transference of CuO species and thermal solid-solid interaction in CuO/CeO2-Al2O3 catalyst prepared by an impregnation method were characterized by in-situ XRD, Raman spectroscopy and H2-TPR techniques. For the catalyst calcined at 300℃, two kinds of CuO species coexist on the surface, that is, highly dispersed and bulk CuO crystalline phase. Four kinds of CuO species are present for the catalyst calcined at 600 ℃, ： （1） highly dispersed CuO, （2） bulk CuO on the surface, （3） bulk CuO in the internal layer of CeO2, and （4） CuAl2O4 formed from CuO-Al2O3 interaction. For the catalyst calcined at 800 ℃,C, besides very little highly dispersed and bulk CuO on the surface, most of the CuO has transferred into the internal layer of CeO2 and the mass of CuAl2O4 are increased. At 900 ℃,, all of CuO has diffused into the internal layer of CeO2 and formed CuAl2O4. The results show that the distribution of CuO species in the catalysts depends on the calcination temperature; the different CuO species can be effectively confirmed by in-situ XRD, Raman spectroscopy and H2-TPR techniques.
