Artificial intelligent aided design and manufacturing have been recognized as one kind of robust data-driven and data-intensive technologies in the integrated computational material engi-neering(ICME)era.Motivated by ...Artificial intelligent aided design and manufacturing have been recognized as one kind of robust data-driven and data-intensive technologies in the integrated computational material engi-neering(ICME)era.Motivated by the dramatical developments of the services of China Railway High-speed series for more than a decade,it is essential to reveal the foundations of lifecycle man-agement of those trains under environmental conditions.Here,the smart design and manufacturing of welded Q350 steel frames of CR200J series are introduced,presenting the capability and opportu-nity of ICME in weight reduction and lifecycle management at a cost-effective approach.In order to address the required fatigue life time enduring more than 9×10^(6)km,the response of optimized frames to the static and the dynamic loads are comprehensively investigated.It is highlighted that the maximum residual stress of the optimized welded frame is reduced to 69 MPa from 477 MPa of previous existing one.Based on the measured stress and acceleration from the railways,the fatigue life of modified frame under various loading modes could fulfil the requirements of the lifecycle man-agement.Moreover,our recent developed intelligent quality control strategy of welding process mediated by machine learning is also introduced,envisioning its application in the intelligent weld-ing.展开更多
A data identifier(DID)is an essential tag or label in all kinds of databases—particularly those related to integrated computational materials engineering(ICME),inheritable integrated intelligent manufacturing(I3M),an...A data identifier(DID)is an essential tag or label in all kinds of databases—particularly those related to integrated computational materials engineering(ICME),inheritable integrated intelligent manufacturing(I3M),and the Industrial Internet ofThings.With the guidance and quick acceleration of the developme nt of advanced materials,as envisioned by official documents worldwide,more investigations are required to construct relative numerical standards for material informatics.This work proposes a universal DID format consisting of a set of build chains,which aligns with the classical form of identifier in both international and national standards,such as ISO/IEC 29168-1:2000,GB/T 27766-2011,GA/T 543.2-2011,GM/T 0006-2012,GJB 7365-2011,SL 325-2014,SL 607-201&WS 363.2-2011,and QX/T 39-2005.Each build chain is made up of capital letters and numbers,with no symbols.Moreover,the total length of each build chain is not restricted,which follows the formation of the Universal Coded Character Set in the international standard of ISO/IEC 10646.Based on these rules,the proposed DID is flexible and convenient for extendi ng and sharing in and between various cloud-based platforms.Accordingly,classical two-dimensional(2D)codes,including the Hanxin Code,Lots Perception Matrix(LP)Code,Quick Response(Q.R)code,Grid Matrix(GM)code,and Data Matrix(DM)Code,can be constructed and precisely recognized and/or decoded by either smart phones or specific machines.By utilizing these 2D codes as the fingerprints of a set of data linked with cloud-based platforms,progress and updates in the composition-processing-structure-property-performance workflow process can be tracked spontaneously,paving a path to accelerate the discovery and manufacture of advanced materials and enhance research productivity,performance,and collaboration.展开更多
In this paper we introduce the wide regime equation of state(WEOS)developed in Institute of Applied Physics and Computational Mathematics(IAPCM).A semi-empirical model of the WEOS is given by a thermodynamically compl...In this paper we introduce the wide regime equation of state(WEOS)developed in Institute of Applied Physics and Computational Mathematics(IAPCM).A semi-empirical model of the WEOS is given by a thermodynamically complete potential of the Helmholtz free energy which combines several theoretical models and has some adjustable parameters calibrated via some experimental and theoretical data.The validation methods of the equation of state in wide regime are presented using copper as a prototype.The results of the WEOS are well consistent with the available theoretical and experimental data,including ab initio cold curve under compression,isotherm,Hugoniot,off-Hugoniot and sound velocity data.It enhances our confidence in the accuracy of the WEOS,which is very important for the validation and verification of equation of state in high temperature and pressure technology.展开更多
We report significant differences in high-pressure properties of vanadium at zero temperature and finite temperature when different projector augmented wave(PAW)potentials are used in simulations based on density func...We report significant differences in high-pressure properties of vanadium at zero temperature and finite temperature when different projector augmented wave(PAW)potentials are used in simulations based on density functional theory.When a PAW potential with only five electrons taken as valence electrons is used,the cold pressures in the high-pressure region are seriously underestimated,and an abnormality occurs in the melting curve of vanadium at about 400 GPa.We show that the reason for these discrepancies lies in the differences in the descriptions of the interatomic force,electron dispersion,and anisotropy of electron bonding obtained from differentPAWpotentials at high pressure,which lead to striking differences in the mechanical stability of the system.We propose a procedure for selecting PAW potentials suitable for simulations at high temperature and high pressure.Our results provide valuable guidance for future simulations of thermodynamic properties under extreme conditions.展开更多
A multi-phase-field model is implemented to investigate the peritectic solidification of Fe-C alloy. The nucleation mode of austenite is based on the local driving force, and two different thicknesses of the primary a...A multi-phase-field model is implemented to investigate the peritectic solidification of Fe-C alloy. The nucleation mode of austenite is based on the local driving force, and two different thicknesses of the primary austenite on the surface of the ferrite equiaxed crystal grain are used as the initial conditions. The simulation shows the multiple interactions of ferrite, austenite, and liquid phases, and the effects of carbon diffusion, which presents the non-equilibrium dynamic process during Fe-C peritectic solidification at the mesoscopic scale. This work not only reveals the influence of the austenite nucleation position, but also clarifies the formation mechanism of liquid phase channels and molten pools. Therefore, the present study contributes to the understanding of the micro-morphology and micro-segregation evolution mechanisms of Fe-C alloy during peritectic solidification.展开更多
Understanding the evolution of irradiation-induced defects is of critical importance for the performance estimation of nuclear materials under irradiation.Hereby,we systematically investigate the influence of He on th...Understanding the evolution of irradiation-induced defects is of critical importance for the performance estimation of nuclear materials under irradiation.Hereby,we systematically investigate the influence of He on the evolution of Frenkel pairs and collision cascades in tungsten(W)via using the object kinetic Monte Carlo(OKMC)method.Our findings suggest that the presence of He has significant effect on the evolution of irradiation-induced defects.On the one hand,the presence of He can facilitate the recombination of vacancies and self-interstitial atoms(SIAs)in W.This can be attributed to the formation of immobile He-SIA complexes,which increases the annihilation probability of vacancies and SIAs.On the other hand,due to the high stability and low mobility of He-vacancy complexes,the growth of large vacancy clusters in W is kinetically suppressed by He addition.Specially,in comparison with the injection of collision cascades and He in sequential way at 1223 K,the average sizes of surviving vacancy clusters in W via simultaneous way are smaller,which is in good agreement with previous experimental observations.These results advocate that the impurity with low concentration has significant effect on the evolution of irradiation-induced defects in materials,and contributes to our understanding of W performance under irradiation.展开更多
Objective: To study the therapeutic effect and mechanisms of recombinant adenovirus Ad-p14ARF in hepatocel- lular carcinoma cell lines. Methods: Morphology and trypan blue assay were adopted to evaluate the proliferat...Objective: To study the therapeutic effect and mechanisms of recombinant adenovirus Ad-p14ARF in hepatocel- lular carcinoma cell lines. Methods: Morphology and trypan blue assay were adopted to evaluate the proliferation of different liver cancer cells after Ad-p14ARF infection. Cell apoptosis was confirmed by detecting phosphatidylserine (PS) externaliza- tion with Annexin V/PI double staining. Western blotting assay analyzed the expression of related proteins. Subcutaneous tumor model of BEL7402 was established to evaluate the therapeutic ability of Ad-p14ARF. Results: Ad-p14ARF suppressed cell growth, proliferation and promoted cell apoptosis of cancer cell lines with different genetic background. Ad-p14ARF in- hibited growth of liver cancer cells (HepG2, BEL7402) in a dose-dependent manner. Ad-p14ARF leaded to overexpression of Bax and p21, which were the downstream regulating genes of p53. Ad-p14ARF suppressed tumor growth significantly in the experimental therapy in nude mice bearing subcutaneous tumor of BEL7402. Conclusion: P14ARF gene is a powerful tumor suppressor gene to be used in cancer gene therapy. It may play an important role in gene therapy against the malignancies in the future.展开更多
We investigate the electronic properties of stableβ-UH3 under high pressure up to 75 GPa within the first-principles DFT+U formalism with pressure-dependent U in a self-consistent calculation,and we find an electroni...We investigate the electronic properties of stableβ-UH3 under high pressure up to 75 GPa within the first-principles DFT+U formalism with pressure-dependent U in a self-consistent calculation,and we find an electronic structure transition at about 20 GPa due to the quantum process of localization and itinerancy for partially filled uranium 5f electrons.The electronic structure transition is examined from four perspectives:magnetization,band structure,density of states,and 5f electron energy.On the basis of the density of states of 5f electrons,we propose an order parameter,namely,the 5f electron energy,to quantify the electronic structure transition under pressure.Analogously to the isostructural transition in 3d systems,β-UH3 retains its magnetic order after the electronic structure transition;however,this is not accompanied by volume collapse at the transition point.Our calculation is helpful for understanding the electronic properties ofβ-UH3 under high pressure.展开更多
Dioecious species evolved from species with monomorphic sex systems in order to achieve overall fitness gains by separating male and female functions.As reproductive organs,unisexual flowers have different reproductiv...Dioecious species evolved from species with monomorphic sex systems in order to achieve overall fitness gains by separating male and female functions.As reproductive organs,unisexual flowers have different reproductive roles and exhibit conspicuous sexual dimorphism.To date,little is known about the temporal variations in and molecular mechanisms underlying the morphology and reproductive costs of dioecious flowers.We investigated male and female flowers of Salix paraplesia in three flowering stages before pollination(the early,blooming and late stages)via transcriptional sequencing as well as metabolite content and phenotypic analysis.We found that a large number of sex-biased genes,rather than sex-limited genes,were responsible for sexual dimorphism in S.paraplesia flowers and that the variation in gene expression in male flowers intensified this situation throughout flower development.The temporal dynamics of sex-biased genes derived from changes in reproductive function during the different flowering stages.Sexually differentiated metabolites related to respiration and flavonoid biosynthesis exhibited the same bias directions as the sex-biased genes.These sex-biased genes were involved mainly in signal transduction,photosynthesis,respiration,cell proliferation,phytochrome biosynthesis,and phenol metabolism;therefore,they resulted in more biomass accumulation and higher energy consumption in male catkins.Our results indicated that sex-biased gene expression in S.paraplesia flowers is associated with different reproductive investments in unisexual flowers;male flowers require a greater reproductive investment to meet their higher biomass accumulation and energy consumption needs.展开更多
Lattice engineering and distortion have been considered one kind of effective strategies for discovering advanced materials.The instinct chemical flexibility of high-entropy oxides(HEOs)motivates/accelerates to tailor...Lattice engineering and distortion have been considered one kind of effective strategies for discovering advanced materials.The instinct chemical flexibility of high-entropy oxides(HEOs)motivates/accelerates to tailor the target properties through phase transformations and lattice distortion.Here,a hybrid knowledge-assisted data-driven machine learning(ML)strategy is utilized to discover the A_(2)B_(2)O_(7)-type HEOs with low thermal conductivity(κ)through 17 rare-earth(RE=Sc,Y,La-Lu)solutes optimized A-site.A designing routine integrating the ML and high throughput first principles has been proposed to predict the key physical parameter(KPPs)correlated to the targetedκof advanced HEOs.Among the smart-designed 6188(5RE_(0.2))_(2)Zr_(2)O_(7)HEOs,the best candidates are addressed and validated by the princi-ples of severe lattice distortion and local phase transformation,which effectively reduceκby the strong multi-phonon scattering and weak interatomic interactions.Particularly,(Sc_(0.2)Y_(0.2)La_(0.2)Ce_(0.2)Pr_(0.2))_(2)Zr_(2)O_(7)with predictedκbelow 1.59 Wm^(−1)K^(−1)is selected to be verified,which matches well with the ex-perimentalκ=1.69 Wm^(−1)K^(−1)at 300 K and could be further decreased to 0.14 Wm^(−1)K^(−1)at 1473 K.Moreover,the coupling effects of lattice vibrations and charges on heat transfer are revealed by the cross-validations of various models,indicating that the weak bonds with low electronegativity and few bond-ing charge density and the lattice distortion(r∗)identified by cation radius ratio(r A/r B)should be the KPPs to decreaseκefficiently.This work supports an intelligent designing strategy with limited atomic and electronic KPPs to accelerate the development of advanced multi-component HEOs with proper-ties/performance at multi-scales.展开更多
This paper addresses the challenge of accurately and timely determining the position of a train,with specific consideration given to the integration of the global navigation satellite system(GNSS)and inertial navigati...This paper addresses the challenge of accurately and timely determining the position of a train,with specific consideration given to the integration of the global navigation satellite system(GNSS)and inertial navigation system(INS).To overcome the increasing errors in the INS during interruptions in GNSS signals,as well as the uncertainty associated with process and measurement noise,a deep learning-based method for train positioning is proposed.This method combines convolutional neural networks(CNN),long short-term memory(LSTM),and the invariant extended Kalman filter(IEKF)to enhance the perception of train positions.It effectively handles GNSS signal interruptions and mitigates the impact of noise.Experimental evaluation and comparisons with existing approaches are provided to illustrate the effectiveness and robustness of the proposed method.展开更多
Lysine acetylation(LysAc)is a conserved and important post-translational modification(PTM)that plays a key role in plant physiological and metabolic processes.Based on advances in Lys-acetylated protein immunoenrichme...Lysine acetylation(LysAc)is a conserved and important post-translational modification(PTM)that plays a key role in plant physiological and metabolic processes.Based on advances in Lys-acetylated protein immunoenrichment and mass-spectrometric technology,LysAc proteomics studies have been performed in many species.Such studies have made substantial contributions to our understanding of plant LysAc,revealing that Lys-acetylated histones and nonhistones are involved in a broad spectrum of plant cellular processes.Here,we present an extensive overview of recent research on plant Lys-acetylproteomes.We provide in-depth insights into the characteristics of plant LysAc modifications and the mechanisms by which LysAc participates in cellular processes and regulates metabolism and physiology during plant growth and development.First,we summarize the characteristics of LysAc,including the properties of Lys-acetylated sites,the motifs that flank Lys-acetylated lysines,and the dynamic alterations in LysAc among different tissues and developmental stages.We also outline a map of Lys-acetylated proteins in the Calvin–Benson cycle and central carbon metabolism–related pathways.We then introduce some examples of the regulation of plant growth,development,and biotic and abiotic stress responses by LysAc.We discuss the interaction between LysAc and Na-terminal acetylation and the crosstalk between LysAc and other PTMs,including phosphorylation and succinylation.Finally,we propose recommendations for future studies in the field.We conclude that LysAc of proteins plays an important role in the regulation of the plant life cycle.展开更多
Metallic amorphous/crystalline(A/C)nanolaminates exhibit excellent ductility while retaining their high strength.However,the underlying physical mechanisms and the resultant structural changes during plastic deformati...Metallic amorphous/crystalline(A/C)nanolaminates exhibit excellent ductility while retaining their high strength.However,the underlying physical mechanisms and the resultant structural changes during plastic deformation still remain unclear.In the present work,the structure-property relationship of CuZr/Cu A/C nanolaminates is established through integrated high-throughput micro-compression tests and molecular dynamics simulations together with high-resolution transmission electron microcopy.The serrated flow of nanolaminates results from the formation of hexagonal-close-packed(HCP)-type stacking faults and twins inside the face-centered-cubic(FCC)Cu nano-grains,the body-centered-cubic(BCC)-type ordering at their grain boundaries,and the crystallization of the amorphous CuZr layers.The serration behavior of CuZr/Cu A/C nanolaminates is determined by several factors,including the formation of dense dislocation networks from the multiplication of initial dislocations that formed after yielding,weak-spots-related configurational-transitions and shear-transition-zone activities,and deformation-induced devitrification.The present work provides an insight into the heterogeneous deformation mechanism of A/C nanolaminates at the atomic scale,and mechanistic base for the microstructural design of self-toughening metallic-glass(MG)-based composites and A/C nanolaminates.展开更多
To assess the impact of the key non-synonymous amino acid substitutions in the RBD of the spike protein of SARS-CoV-2 variant B.1.617.1(dominant variant identified in the current India outbreak)on the infectivity and ...To assess the impact of the key non-synonymous amino acid substitutions in the RBD of the spike protein of SARS-CoV-2 variant B.1.617.1(dominant variant identified in the current India outbreak)on the infectivity and neutralization activities of the immune sera,L452R and E484Q(L452R-E484Q variant),pseudotyped virus was constructed(with the D614G background).The impact on binding with the neutralizing antibodies was also assessed with an ELISA assay.Pseudotyped virus carrying a L452R-E484Q variant showed a comparable infectivity compared with D614G.However,there was a significant reduction in the neutralization activity of the immune sera from non-human primates vaccinated with a recombinant receptor binding domain(RBD)protein,convalescent patients,and healthy vaccinees vaccinated with anmRNA vaccine.In addition,there was a reduction in binding of L452R-E484Q-D614G protein to the antibodies of theimmune sera fromvaccinated nonhuman primates.These results highlight the interplay between infectivity and other biologic factors involved in the natural evolution of SARS-CoV-2.Reduced neutralization activities against the L452R-E484Q variant will have an impact on health authority planning and implications for the vaccination strategy/newvaccine development.展开更多
In this paper,the common-mode radiation characteristic of the connection between a cable and a conductor is analyzed by the electric field integral function(EFIF)and the method of moment(MoM).The RWG basis function is...In this paper,the common-mode radiation characteristic of the connection between a cable and a conductor is analyzed by the electric field integral function(EFIF)and the method of moment(MoM).The RWG basis function is adopted as the conductor basis function,the pulse basis function as the wire basis function and the juncture employs Costa basis function.A scheme of singular region separation is proposed to overcome the integration singularity of juncture matrix elements.Some new conclusions of the common-mode radiation characteristics with the metal case are obtained by numeration.展开更多
基金supported by the National Basic Scientific Research Project of China (No.JCKY2020607B003)CRRC (No.202CDA001)
文摘Artificial intelligent aided design and manufacturing have been recognized as one kind of robust data-driven and data-intensive technologies in the integrated computational material engi-neering(ICME)era.Motivated by the dramatical developments of the services of China Railway High-speed series for more than a decade,it is essential to reveal the foundations of lifecycle man-agement of those trains under environmental conditions.Here,the smart design and manufacturing of welded Q350 steel frames of CR200J series are introduced,presenting the capability and opportu-nity of ICME in weight reduction and lifecycle management at a cost-effective approach.In order to address the required fatigue life time enduring more than 9×10^(6)km,the response of optimized frames to the static and the dynamic loads are comprehensively investigated.It is highlighted that the maximum residual stress of the optimized welded frame is reduced to 69 MPa from 477 MPa of previous existing one.Based on the measured stress and acceleration from the railways,the fatigue life of modified frame under various loading modes could fulfil the requirements of the lifecycle man-agement.Moreover,our recent developed intelligent quality control strategy of welding process mediated by machine learning is also introduced,envisioning its application in the intelligent weld-ing.
基金This work was financially supported by the National Key Research and Development Program of China(2018YFB0703801,2018YFB0703802,2016YFB0701303,and 2016YFB0701304)CRRC Tangshan Co.,Ltd.(201750463031).Special thanks to Professor Hong Wang at Shanghai Jiao Tong University for the fruitful discussions and the constructive suggestions/comments.
文摘A data identifier(DID)is an essential tag or label in all kinds of databases—particularly those related to integrated computational materials engineering(ICME),inheritable integrated intelligent manufacturing(I3M),and the Industrial Internet ofThings.With the guidance and quick acceleration of the developme nt of advanced materials,as envisioned by official documents worldwide,more investigations are required to construct relative numerical standards for material informatics.This work proposes a universal DID format consisting of a set of build chains,which aligns with the classical form of identifier in both international and national standards,such as ISO/IEC 29168-1:2000,GB/T 27766-2011,GA/T 543.2-2011,GM/T 0006-2012,GJB 7365-2011,SL 325-2014,SL 607-201&WS 363.2-2011,and QX/T 39-2005.Each build chain is made up of capital letters and numbers,with no symbols.Moreover,the total length of each build chain is not restricted,which follows the formation of the Universal Coded Character Set in the international standard of ISO/IEC 10646.Based on these rules,the proposed DID is flexible and convenient for extendi ng and sharing in and between various cloud-based platforms.Accordingly,classical two-dimensional(2D)codes,including the Hanxin Code,Lots Perception Matrix(LP)Code,Quick Response(Q.R)code,Grid Matrix(GM)code,and Data Matrix(DM)Code,can be constructed and precisely recognized and/or decoded by either smart phones or specific machines.By utilizing these 2D codes as the fingerprints of a set of data linked with cloud-based platforms,progress and updates in the composition-processing-structure-property-performance workflow process can be tracked spontaneously,paving a path to accelerate the discovery and manufacture of advanced materials and enhance research productivity,performance,and collaboration.
基金supported by the National Natural Science Foundation of China(Nos.10804011,11176002).
文摘In this paper we introduce the wide regime equation of state(WEOS)developed in Institute of Applied Physics and Computational Mathematics(IAPCM).A semi-empirical model of the WEOS is given by a thermodynamically complete potential of the Helmholtz free energy which combines several theoretical models and has some adjustable parameters calibrated via some experimental and theoretical data.The validation methods of the equation of state in wide regime are presented using copper as a prototype.The results of the WEOS are well consistent with the available theoretical and experimental data,including ab initio cold curve under compression,isotherm,Hugoniot,off-Hugoniot and sound velocity data.It enhances our confidence in the accuracy of the WEOS,which is very important for the validation and verification of equation of state in high temperature and pressure technology.
基金This work is supported by the Science Challenge Project(Grant No.TZ2016001)the National Natural Science Foundation of China(Grant Nos.U1930401,51671033,and 12004048).
文摘We report significant differences in high-pressure properties of vanadium at zero temperature and finite temperature when different projector augmented wave(PAW)potentials are used in simulations based on density functional theory.When a PAW potential with only five electrons taken as valence electrons is used,the cold pressures in the high-pressure region are seriously underestimated,and an abnormality occurs in the melting curve of vanadium at about 400 GPa.We show that the reason for these discrepancies lies in the differences in the descriptions of the interatomic force,electron dispersion,and anisotropy of electron bonding obtained from differentPAWpotentials at high pressure,which lead to striking differences in the mechanical stability of the system.We propose a procedure for selecting PAW potentials suitable for simulations at high temperature and high pressure.Our results provide valuable guidance for future simulations of thermodynamic properties under extreme conditions.
基金Project supported by the Science Challenge Project,China(Grant No.TZZT2019-D1-03)the National Natural Science Foundation of China(Grant No.51972028)the National Key Research and Development Program of China(Grant No.2019YFA0307900)。
文摘A multi-phase-field model is implemented to investigate the peritectic solidification of Fe-C alloy. The nucleation mode of austenite is based on the local driving force, and two different thicknesses of the primary austenite on the surface of the ferrite equiaxed crystal grain are used as the initial conditions. The simulation shows the multiple interactions of ferrite, austenite, and liquid phases, and the effects of carbon diffusion, which presents the non-equilibrium dynamic process during Fe-C peritectic solidification at the mesoscopic scale. This work not only reveals the influence of the austenite nucleation position, but also clarifies the formation mechanism of liquid phase channels and molten pools. Therefore, the present study contributes to the understanding of the micro-morphology and micro-segregation evolution mechanisms of Fe-C alloy during peritectic solidification.
基金Project supported by the Science Challenge Project(Grant No.TZ2018002)the National Natural Science Foundation of China(Grant No.11905135)the National MCF Energy R&D Program of China(Grant No.2018YFE0308103).
文摘Understanding the evolution of irradiation-induced defects is of critical importance for the performance estimation of nuclear materials under irradiation.Hereby,we systematically investigate the influence of He on the evolution of Frenkel pairs and collision cascades in tungsten(W)via using the object kinetic Monte Carlo(OKMC)method.Our findings suggest that the presence of He has significant effect on the evolution of irradiation-induced defects.On the one hand,the presence of He can facilitate the recombination of vacancies and self-interstitial atoms(SIAs)in W.This can be attributed to the formation of immobile He-SIA complexes,which increases the annihilation probability of vacancies and SIAs.On the other hand,due to the high stability and low mobility of He-vacancy complexes,the growth of large vacancy clusters in W is kinetically suppressed by He addition.Specially,in comparison with the injection of collision cascades and He in sequential way at 1223 K,the average sizes of surviving vacancy clusters in W via simultaneous way are smaller,which is in good agreement with previous experimental observations.These results advocate that the impurity with low concentration has significant effect on the evolution of irradiation-induced defects in materials,and contributes to our understanding of W performance under irradiation.
基金Supported by the National Key Basic Research Program (NKBRP, 973 program, No. 2002CB513100-8).
文摘Objective: To study the therapeutic effect and mechanisms of recombinant adenovirus Ad-p14ARF in hepatocel- lular carcinoma cell lines. Methods: Morphology and trypan blue assay were adopted to evaluate the proliferation of different liver cancer cells after Ad-p14ARF infection. Cell apoptosis was confirmed by detecting phosphatidylserine (PS) externaliza- tion with Annexin V/PI double staining. Western blotting assay analyzed the expression of related proteins. Subcutaneous tumor model of BEL7402 was established to evaluate the therapeutic ability of Ad-p14ARF. Results: Ad-p14ARF suppressed cell growth, proliferation and promoted cell apoptosis of cancer cell lines with different genetic background. Ad-p14ARF in- hibited growth of liver cancer cells (HepG2, BEL7402) in a dose-dependent manner. Ad-p14ARF leaded to overexpression of Bax and p21, which were the downstream regulating genes of p53. Ad-p14ARF suppressed tumor growth significantly in the experimental therapy in nude mice bearing subcutaneous tumor of BEL7402. Conclusion: P14ARF gene is a powerful tumor suppressor gene to be used in cancer gene therapy. It may play an important role in gene therapy against the malignancies in the future.
基金We acknowledge support from the National Key Research and Development Program of China under Grant No.2021YFB3501503from the National Natural Science Foundation of China under Grant Nos.12004048 and U1930401.
文摘We investigate the electronic properties of stableβ-UH3 under high pressure up to 75 GPa within the first-principles DFT+U formalism with pressure-dependent U in a self-consistent calculation,and we find an electronic structure transition at about 20 GPa due to the quantum process of localization and itinerancy for partially filled uranium 5f electrons.The electronic structure transition is examined from four perspectives:magnetization,band structure,density of states,and 5f electron energy.On the basis of the density of states of 5f electrons,we propose an order parameter,namely,the 5f electron energy,to quantify the electronic structure transition under pressure.Analogously to the isostructural transition in 3d systems,β-UH3 retains its magnetic order after the electronic structure transition;however,this is not accompanied by volume collapse at the transition point.Our calculation is helpful for understanding the electronic properties ofβ-UH3 under high pressure.
基金the Second Tibetan Plateau Scientific Expedition and Research Program(2019QZKK0404)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA20020401)+1 种基金the National Natural Science Foundation of China(31770650)the Fundamental Research Funds for the Central Universities.
文摘Dioecious species evolved from species with monomorphic sex systems in order to achieve overall fitness gains by separating male and female functions.As reproductive organs,unisexual flowers have different reproductive roles and exhibit conspicuous sexual dimorphism.To date,little is known about the temporal variations in and molecular mechanisms underlying the morphology and reproductive costs of dioecious flowers.We investigated male and female flowers of Salix paraplesia in three flowering stages before pollination(the early,blooming and late stages)via transcriptional sequencing as well as metabolite content and phenotypic analysis.We found that a large number of sex-biased genes,rather than sex-limited genes,were responsible for sexual dimorphism in S.paraplesia flowers and that the variation in gene expression in male flowers intensified this situation throughout flower development.The temporal dynamics of sex-biased genes derived from changes in reproductive function during the different flowering stages.Sexually differentiated metabolites related to respiration and flavonoid biosynthesis exhibited the same bias directions as the sex-biased genes.These sex-biased genes were involved mainly in signal transduction,photosynthesis,respiration,cell proliferation,phytochrome biosynthesis,and phenol metabolism;therefore,they resulted in more biomass accumulation and higher energy consumption in male catkins.Our results indicated that sex-biased gene expression in S.paraplesia flowers is associated with different reproductive investments in unisexual flowers;male flowers require a greater reproductive investment to meet their higher biomass accumulation and energy consumption needs.
基金supported by National defense ba-sic scientific research(Grant Nos.2022-JCKY-JJ-1086 and 211-CXCY-N103-03-04-00).
文摘Lattice engineering and distortion have been considered one kind of effective strategies for discovering advanced materials.The instinct chemical flexibility of high-entropy oxides(HEOs)motivates/accelerates to tailor the target properties through phase transformations and lattice distortion.Here,a hybrid knowledge-assisted data-driven machine learning(ML)strategy is utilized to discover the A_(2)B_(2)O_(7)-type HEOs with low thermal conductivity(κ)through 17 rare-earth(RE=Sc,Y,La-Lu)solutes optimized A-site.A designing routine integrating the ML and high throughput first principles has been proposed to predict the key physical parameter(KPPs)correlated to the targetedκof advanced HEOs.Among the smart-designed 6188(5RE_(0.2))_(2)Zr_(2)O_(7)HEOs,the best candidates are addressed and validated by the princi-ples of severe lattice distortion and local phase transformation,which effectively reduceκby the strong multi-phonon scattering and weak interatomic interactions.Particularly,(Sc_(0.2)Y_(0.2)La_(0.2)Ce_(0.2)Pr_(0.2))_(2)Zr_(2)O_(7)with predictedκbelow 1.59 Wm^(−1)K^(−1)is selected to be verified,which matches well with the ex-perimentalκ=1.69 Wm^(−1)K^(−1)at 300 K and could be further decreased to 0.14 Wm^(−1)K^(−1)at 1473 K.Moreover,the coupling effects of lattice vibrations and charges on heat transfer are revealed by the cross-validations of various models,indicating that the weak bonds with low electronegativity and few bond-ing charge density and the lattice distortion(r∗)identified by cation radius ratio(r A/r B)should be the KPPs to decreaseκefficiently.This work supports an intelligent designing strategy with limited atomic and electronic KPPs to accelerate the development of advanced multi-component HEOs with proper-ties/performance at multi-scales.
基金supported by the National Natural Science Foundation of China(Nos.61925302,62273027)the Beijing Natural Science Foundation(L211021).
文摘This paper addresses the challenge of accurately and timely determining the position of a train,with specific consideration given to the integration of the global navigation satellite system(GNSS)and inertial navigation system(INS).To overcome the increasing errors in the INS during interruptions in GNSS signals,as well as the uncertainty associated with process and measurement noise,a deep learning-based method for train positioning is proposed.This method combines convolutional neural networks(CNN),long short-term memory(LSTM),and the invariant extended Kalman filter(IEKF)to enhance the perception of train positions.It effectively handles GNSS signal interruptions and mitigates the impact of noise.Experimental evaluation and comparisons with existing approaches are provided to illustrate the effectiveness and robustness of the proposed method.
基金This work was supported by the Second Tibetan Plateau Scientific Expedition and Research Program(2019QZKK0404)the National Natural Science Foundation of China(31770650)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA20020401)the Fundamental Research Funds for the Central Universities.
文摘Lysine acetylation(LysAc)is a conserved and important post-translational modification(PTM)that plays a key role in plant physiological and metabolic processes.Based on advances in Lys-acetylated protein immunoenrichment and mass-spectrometric technology,LysAc proteomics studies have been performed in many species.Such studies have made substantial contributions to our understanding of plant LysAc,revealing that Lys-acetylated histones and nonhistones are involved in a broad spectrum of plant cellular processes.Here,we present an extensive overview of recent research on plant Lys-acetylproteomes.We provide in-depth insights into the characteristics of plant LysAc modifications and the mechanisms by which LysAc participates in cellular processes and regulates metabolism and physiology during plant growth and development.First,we summarize the characteristics of LysAc,including the properties of Lys-acetylated sites,the motifs that flank Lys-acetylated lysines,and the dynamic alterations in LysAc among different tissues and developmental stages.We also outline a map of Lys-acetylated proteins in the Calvin–Benson cycle and central carbon metabolism–related pathways.We then introduce some examples of the regulation of plant growth,development,and biotic and abiotic stress responses by LysAc.We discuss the interaction between LysAc and Na-terminal acetylation and the crosstalk between LysAc and other PTMs,including phosphorylation and succinylation.Finally,we propose recommendations for future studies in the field.We conclude that LysAc of proteins plays an important role in the regulation of the plant life cycle.
基金financially supported by the National Natural Science Foundation of China(Nos.51690163 and 51601147)the Science Challenge Project(No.TZZT2019-D1.5)+4 种基金the Ministry of Science and Technology of China(No.2017YFA0700700)the United States National Science Foundation(Nos.DMR-1006557,1611180,and 1809640)the Fundamental Research Funds for the Central Universities in China(No.G2016KY0302)the CyberStar cluster funded by NSF through grant No.OCI-0821527the XSEDE clusters supported by NSF through Grant No.ACI-1053575。
文摘Metallic amorphous/crystalline(A/C)nanolaminates exhibit excellent ductility while retaining their high strength.However,the underlying physical mechanisms and the resultant structural changes during plastic deformation still remain unclear.In the present work,the structure-property relationship of CuZr/Cu A/C nanolaminates is established through integrated high-throughput micro-compression tests and molecular dynamics simulations together with high-resolution transmission electron microcopy.The serrated flow of nanolaminates results from the formation of hexagonal-close-packed(HCP)-type stacking faults and twins inside the face-centered-cubic(FCC)Cu nano-grains,the body-centered-cubic(BCC)-type ordering at their grain boundaries,and the crystallization of the amorphous CuZr layers.The serration behavior of CuZr/Cu A/C nanolaminates is determined by several factors,including the formation of dense dislocation networks from the multiplication of initial dislocations that formed after yielding,weak-spots-related configurational-transitions and shear-transition-zone activities,and deformation-induced devitrification.The present work provides an insight into the heterogeneous deformation mechanism of A/C nanolaminates at the atomic scale,and mechanistic base for the microstructural design of self-toughening metallic-glass(MG)-based composites and A/C nanolaminates.
文摘To assess the impact of the key non-synonymous amino acid substitutions in the RBD of the spike protein of SARS-CoV-2 variant B.1.617.1(dominant variant identified in the current India outbreak)on the infectivity and neutralization activities of the immune sera,L452R and E484Q(L452R-E484Q variant),pseudotyped virus was constructed(with the D614G background).The impact on binding with the neutralizing antibodies was also assessed with an ELISA assay.Pseudotyped virus carrying a L452R-E484Q variant showed a comparable infectivity compared with D614G.However,there was a significant reduction in the neutralization activity of the immune sera from non-human primates vaccinated with a recombinant receptor binding domain(RBD)protein,convalescent patients,and healthy vaccinees vaccinated with anmRNA vaccine.In addition,there was a reduction in binding of L452R-E484Q-D614G protein to the antibodies of theimmune sera fromvaccinated nonhuman primates.These results highlight the interplay between infectivity and other biologic factors involved in the natural evolution of SARS-CoV-2.Reduced neutralization activities against the L452R-E484Q variant will have an impact on health authority planning and implications for the vaccination strategy/newvaccine development.
文摘In this paper,the common-mode radiation characteristic of the connection between a cable and a conductor is analyzed by the electric field integral function(EFIF)and the method of moment(MoM).The RWG basis function is adopted as the conductor basis function,the pulse basis function as the wire basis function and the juncture employs Costa basis function.A scheme of singular region separation is proposed to overcome the integration singularity of juncture matrix elements.Some new conclusions of the common-mode radiation characteristics with the metal case are obtained by numeration.