A variable-fidelity method can remarkably improve the efficiency of a design optimization based on a high-fidelity and expensive numerical simulation,with assistance of lower-fidelity and cheaper simulation(s).However...A variable-fidelity method can remarkably improve the efficiency of a design optimization based on a high-fidelity and expensive numerical simulation,with assistance of lower-fidelity and cheaper simulation(s).However,most existing works only incorporate‘‘two"levels of fidelity,and thus efficiency improvement is very limited.In order to reduce the number of high-fidelity simulations as many as possible,there is a strong need to extend it to three or more fidelities.This article proposes a novel variable-fidelity optimization approach with application to aerodynamic design.Its key ingredient is the theory and algorithm of a Multi-level Hierarchical Kriging(MHK),which is referred to as a surrogate model that can incorporate simulation data with arbitrary levels of fidelity.The high-fidelity model is defined as a CFD simulation using a fine grid and the lower-fidelity models are defined as the same CFD model but with coarser grids,which are determined through a grid convergence study.First,sampling shapes are selected for each level of fidelity via technique of Design of Experiments(DoE).Then,CFD simulations are conducted and the output data of varying fidelity is used to build initial MHK models for objective(e.g.C_D)and constraint(e.g.C_L,C_m)functions.Next,new samples are selected through infillsampling criteria and the surrogate models are repetitively updated until a global optimum is found.The proposed method is validated by analytical test cases and applied to aerodynamic shape optimization of a NACA0012 airfoil and an ONERA M6 wing in transonic flows.The results confirm that the proposed method can significantly improve the optimization efficiency and apparently outperforms the existing single-fidelity or two-level-fidelity method.展开更多
An experimental analysis on the subsequent yield-surfaces evolution using multiple specimens is presented for a 45 steel after a prescribed pre-strain loading in three different directions respectively, and the yieldi...An experimental analysis on the subsequent yield-surfaces evolution using multiple specimens is presented for a 45 steel after a prescribed pre-strain loading in three different directions respectively, and the yielding is defined by a designated offsetting strain. The size of the subsequent yield surface is found smaller than the initial yield surface; the negative cross effects are observed in the normal loading direction, its shape is not a Mises circle but has a rather blunt nose in loading direction and flat in the opposite. These results strongly depend on the loading path and the prescribed offset plastic strain. The plastic flow direction to the subsequent yield surface is investigated, and it is found that the plastic flow direction deviates from the normal flow rule. The deviation differs from preloading case to preloading case. And the plastic flow direction would have a larger deviation from the normal of the yield surface, if the subsequent yield was defined by a smaller offset strain. Furthermore, the experiments are simulated using the Chaboche model, and the results show that it can rationally predict yield-surface only when yield is defined by a fairly large offset strain.展开更多
To investigate the relationship between macro-plastic behavior and meso-deformation mechanism of Mg alloy AZ31, the mathematical models for various deformation mechanisms of slip, twinning and detwinning are establish...To investigate the relationship between macro-plastic behavior and meso-deformation mechanism of Mg alloy AZ31, the mathematical models for various deformation mechanisms of slip, twinning and detwinning are established, respectively. Furthermore, in order to capture the Bauschinger effect under cyclic loading, the back stress is introduced into the three independent deformation mechanisms, respectively. Finally, using the above-mentioned model, a new cyclic plastic constitutive model based on the constitutive theory of crystal deformation for magnesium alloy is established. On this basis, the numerical simulation for AZ31 under cyclic loading with the axial strain amplitude of 1.2% is carried out in accordance with the aforementioned crystal plas- ticity theory associated with the representative volume element model. The comparison between the stress-strain curves obtained from the simulation and the experiments shows that the macro- scopic mechanical responses predicted using the proposed model are in good agreement with the experimental results. In particular, the unique characteristics of cyclic macro-plastic behavior observed in the experiments can be satisfactorily captured by the presented crystal plasticity model. At the mesoscale, these features are caused by the alternate occurrence of twinning and detwinning mechanisms. The further analysis of meso-plastic behavior shows that there are het- erogeneous distributions of twinning, stress-strain and stress triaxiality in polycrystal under cyclic loading.展开更多
Large-scale structure(LSS)surveys will increasingly provide stringent constraints on our cosmological models.Recently,the density-marked correlation function(MCF)has been introduced,offering an easily computable densi...Large-scale structure(LSS)surveys will increasingly provide stringent constraints on our cosmological models.Recently,the density-marked correlation function(MCF)has been introduced,offering an easily computable density-correlation statistic.Simulations have demonstrated that MCFs offer additional,independent constraints on cosmological models beyond the standard two-point correlation(2PCF).In this study,we apply MCFs for the first time to SDSS CMASS data,aiming to investigate the statistical information regarding clustering and anisotropy properties in the Universe and assess the performance of various weighting schemes in MCFs,and finally obtain constraints onΩ_(m).Upon analyzing the CMASS data,we observe that,by combining different weights(α=[-0.2,0,0.2,0.6]),the MCFs provide a tight and independent constraint on the cosmological parameterΩ_(m),yieldingΩ_(m)=0.293±0.006 at the 1σlevel,which represents a significant reduction in the statistical error by a factor of 3.4 compared to that from 2PCF.Our constraint is consistent with recent findings from the small-scale clustering of BOSS galaxies(Zhai et al.Astronphys.J.948,99(2023))within the 1σlevel.However,we also find that our estimate is lower than the Planck measurements by about 2.6σ,indicating the potential presence of new physics beyond the standard cosmological model if all the systematics are fully corrected.The method outlined in this study can be extended to other surveys and datasets,allowing for the constraint of other cosmological parameters.Additionally,it serves as a valuable tool for forthcoming emulator analysis on the Chinese Space Station Telescope(CSST).展开更多
Parasitoids are key regulators in ecological communities and widely used as agents in biocontrol programmes.The fall armyworm,Spodoptera frugiperda,recently invaded multiple continents and caused substantial economic ...Parasitoids are key regulators in ecological communities and widely used as agents in biocontrol programmes.The fall armyworm,Spodoptera frugiperda,recently invaded multiple continents and caused substantial economic losses in agriculture.Pyemotes zhonghuajia,a newly identified mite parasitoid,has shown potential for controlling various agricultural insect pests.Therefore,this study tested the performance of P.zhonghuajia in parasitising S.frugiperda.We also investigated the sublethal effects of parasitism by P.zhonghuajia on host fitness traits,transgenerational impacts,and cellular and humoral immunity.Our result showed that the fifth-instar larvae of S.frugiperda parasitised by 40 P.zhonghuajia were all dead(i.e.,a lethal effect),while parasitism by 5 or 10 P.zhonghuajia was considered sublethal since many S.frugiperda survived to adulthood and produced offspring after mating.The sublethal influences from parasitism by P.zhonghuajia resulted in reduced pupal weight,adult emergence rate and fecundity,but increased developmental time and longevity.Parasitism at both lethal(40 mites)and sublethal(10 mites)levels impaired the cellular and humoral immunity of S.frugiperda.This study presents the first empirical evidence that mite parasitoids can negatively influence host immunity.Moreover,it provides insights into the biocontrol potential of mite parasitoids and their interactions with hosts.展开更多
Based on the thermodynamic theory, an orthotropic damage constitutive model was developed to describe the nonlinear mechanical behavior of C/SiC composites. The different nonlinear kinematic and isotropic hardening fu...Based on the thermodynamic theory, an orthotropic damage constitutive model was developed to describe the nonlinear mechanical behavior of C/SiC composites. The different nonlinear kinematic and isotropic hardening functions were adopted to describe accurately the damage evolution processes. The damage variables were defined with the damaged modulus and the initial undamaged modulus on energy equivalence principle. The initial orthotropy and damage coupling were presented in the damage yield function. Tensile and in-plane shear loading and unloading tests were performed, and a good agreement between the model and the experimental results was achieved.展开更多
Metabolites play important roles in numerous cell biology processes,such as cell proliferation,differentiation,stress response,and cell death[1].Recently,lactate and lactate-derived lysine residue lactylation(Kla)have...Metabolites play important roles in numerous cell biology processes,such as cell proliferation,differentiation,stress response,and cell death[1].Recently,lactate and lactate-derived lysine residue lactylation(Kla)have emerged as newly discovered epigenetic modifications that play critical roles in various physiological and pathological processes.In the history of lactate research,we can categorize the studies into three mile stones(Fig.S1 online).展开更多
Cell fate determination as a fundamental question in cell biology has been extensively studied at different regulatory levels for many years.However,the mechanisms of multilevel regulation of cell fate determination r...Cell fate determination as a fundamental question in cell biology has been extensively studied at different regulatory levels for many years.However,the mechanisms of multilevel regulation of cell fate determination remain unclear.Recently,we have proposed an Epigenome-Metabolome-Epigenome(E-M-E)signaling cascade model to describe the cross-over cooperation during mouse somatic cell reprogramming.In this review,we summarize the broad roles of E-M-E signaling cascade in different cell biological processes,including cell differentiation and dedifferentiation,cell specialization,cell proliferation,and cell pathologic processes.Precise E-M-E signaling cascades are critical in these cell biological processes,and it is of worth to explore each step of E-M-E signaling cascade.E-M-E signaling cascade model sheds light on and may open a window to explore the mechanisms of multilevel regulation of cell biological processes.展开更多
The tension necking of FCC copper single crystal specimen with a square cross section was analyzed under the slip deformation mechanism. The actual clamp manner of the specimen was modeled by setting correlative bound...The tension necking of FCC copper single crystal specimen with a square cross section was analyzed under the slip deformation mechanism. The actual clamp manner of the specimen was modeled by setting correlative boundary condition,and the small angle deflection between tension loading axis and crystallography axis [100] was taken into account. The finite deformation numerical analysis of three-dimensional necking deformation for the specimen was performed by apply-ing crystal plasticity theory associated with a numerical algorithm suggested by the first author. According to the comparison with experimental observation,the fact was confirmed that the numerical results could describe the loading elongation curve of the copper single crystal specimen under large strain tension reasonably,and the method could be used to investigate the necking characteristic in neck shape and the effect due to the small angle deflection. Further,the investigation into the influence of specimen cross-section shape on necking was also performed;the results on mechanical response and neck profile evolution obtained through modeling of cylindrical specimen were compared with those obtained with square cross-section specimen.展开更多
Based on the ABAQUS platform for finite element analysis, the extended finite element method (XFEM) considering elastoplastic constitutive relationship is developed, by which the displacement discontinuity across the ...Based on the ABAQUS platform for finite element analysis, the extended finite element method (XFEM) considering elastoplastic constitutive relationship is developed, by which the displacement discontinuity across the crack surface and the strong nonlinearity near the crack tip can be described more accurately. The strip specimens with unilateral cracks and central cracks under uniaxial tension are simulated using the XFEM and the FEM, respectively. The J-integral across the crack on each incremen t is calcula ted using the equivale nt domain integral met hod (EDIM), the interaction integral met hod and the FEM, respectively. The effec ts of mesh size and mesh shape near the crack tip, element type and different calculation methods on the accuracy of J-integral are analyzed. The simulation results show that the XFEM is more accurate than the FEM with the same element size and type. The fracture tests of cast iron specimens with unilateral cracks under uniaxial tension are performed, and the J-integral criterion is valid to predict the fracture initiation in numerical simulation. The critical value of J-integral is calculated using the EDIM of the XFEM. The comparisons demonstrate that the simulated elastoplastic load-displacement curves with the XFEM are in good agreement with the experimental results.展开更多
Taking the planning practice of green transportation in Sino-Singapore Tianjin Eco-city as an example,the key factors and design strategies for its healthy development were summarized from the aspects of the coordinat...Taking the planning practice of green transportation in Sino-Singapore Tianjin Eco-city as an example,the key factors and design strategies for its healthy development were summarized from the aspects of the coordination of land use and traffic development,the development of the public transport plus slow traffic model,and the development of reasonable and humanized traffic management measures,through analyzing the connotation and scale of green cluster.In addition,the design strategies of the green transportation concept suitable for the development of urban clusters represented by Guangming New District in Shenzhen were proposed,so as to provide a reference for promoting better the coordinated development of green traffic and cities,and maximizing the economic,social and environmental benefits of green transportation development.展开更多
Kin recognition has been widely observed in various taxa.Cannibalism avoidance may be a strong driver for the evolution of kin recognition,as it may avoid a reduction in inclusive fitness.Kin recognition has recently ...Kin recognition has been widely observed in various taxa.Cannibalism avoidance may be a strong driver for the evolution of kin recognition,as it may avoid a reduction in inclusive fitness.Kin recognition has recently been observed in a generalist phytoseiid,Amblyseius herbicolus(Acari:Phytoseiidae).This study experimentally examined the degree of relatedness needed between prey larvae and cannibal adults of A.herbicolus for the occurrence of kin discrimination.The adults were individually placed in enclosed arenas with two prey,a daughter and a more distant related larva,to observe their cannibalizing choice.The adults of A.herbicolus did not discriminate between close relatives(daughter versus niece)but preferably cannibalized more distant kin(i.e.,first and second cousins once removed).Phenotype matching and familiarization seem prominent as recognition mechanisms used by A.herbicolus adults.The effect of learning on kin recognition through prior contact in A.herbicolus requires further investigation.Studies on other adaptive functions of kin recognition of A.herbicolus,such as cooperation and parental care,may provide meaningful insights.展开更多
The investigation based on experiments and crystal plasticity simulation is carried out to undertake research on mesodeformation inhomogeneity of metals under cyclic loading at grain level.Symmetrical tension-compress...The investigation based on experiments and crystal plasticity simulation is carried out to undertake research on mesodeformation inhomogeneity of metals under cyclic loading at grain level.Symmetrical tension-compression cycle tests are performed on pure copper specimens to observe the inhomogeneous distribution of slip deformation and its evolution with cycle number.Cyclic hardening process and stable hysteretic behavior of pure copper under cyclic loading are simulated by applying a crystal plasticity constitutive model including nonlinear kinematic hardening associated with the polycrystalline representative volume element(RVE)constructed by Voronoi tessellation.Inhomogeneous deformation processes of materials under six different strain amplitudes are simulated by 1600 cycles,respectively.We discuss the variation law of the inhomogeneous meso-deformation distribution of material with the increase in cycle number,and research the rationality of characterizing the inhomogeneous deformation distribution and variation with the statistical standard deviation of the micro-longitudinal strain or the statistical average of the first principal strain based on the statistical analysis of the inhomogeneous deformation of the polycrystalline RVE model during the cycling process.It is found that these two parameters are related to and approximately inversely proportional to the length of measuring gauge.展开更多
Located in Wutiao Harbor of Tainan City, Hai'an Road used to be a significant trade logistics center and the most flourishing commercial area until the construction of underground street in Hai'an Road and the...Located in Wutiao Harbor of Tainan City, Hai'an Road used to be a significant trade logistics center and the most flourishing commercial area until the construction of underground street in Hai'an Road and the beginning of broadening project which brought irreparable and huge damages to this historic street. Fortunately, Artistic Street Renovation Plan was implemented in 2004 and succeeded in revitalizing Hai'an Road. The implementation of this plan transformed this street into an art museum to which lots of photographers and artists were attracted and made a pilgrimage. Besides, it remodeled the local cultural identity and enhanced the community cohesion. Based on the in-depth research on the integral process of Artistic Street Renovation Plan on Hai'an Road, this paper focuses on the analysis of multivariate stakeholders' partnership among government, inhabitants, curatorial group and artists so as to propose protective methods and developmental ideas for historical streets.展开更多
Dafen Oil Painting Village, the largest oil painting village in current China, takes cultural industries like creation and wholesale of oil paintings as the pillar. As one of the urban villages in Shenzhen, Dafen Vill...Dafen Oil Painting Village, the largest oil painting village in current China, takes cultural industries like creation and wholesale of oil paintings as the pillar. As one of the urban villages in Shenzhen, Dafen Village not only has the common characteristics of urban morphology as ordinary urban villages, but also has something unique. In this paper, study of the urban morphology of Dafen Oil Painting Village is mainly from 3 aspects: firstly, the formation of street space in Dafen Village; secondly, analysis of the status of urban morphology of Dafen Village; thirdly, the plane layout and public space of Dafen Village. In the end, this paper put forward some suggestions about the future development of urban morphology and space layout in Dafen Village.展开更多
Pluripotent stem cells hold tremendous promise for regenerative medicine.The mechanisms underlying the acquisition and loss of pluripotency have been revealed at multiple levels.Subcellular mechanisms such as metaboli...Pluripotent stem cells hold tremendous promise for regenerative medicine.The mechanisms underlying the acquisition and loss of pluripotency have been revealed at multiple levels.Subcellular mechanisms such as metabolic and organelle remodeling are emerging as critical for pluripotent cell fate transitions.Understanding the rules and roles of organelle remodeling will not only provide important insights into pluripotency regulation,but also help improving application in regenerative medicine.In this review,we summarize recent discoveries in organelle remodeling during the acquisition and loss of pluripotency and discuss how membrane lipids orchestrate organelle remodeling and drive nuclear gene expression.展开更多
Yilan is a successful model of agricultural county transformation during Taiwan's rapid development period. Its urbanization can be considered as an application and evolution of the Garden City concept. With the e...Yilan is a successful model of agricultural county transformation during Taiwan's rapid development period. Its urbanization can be considered as an application and evolution of the Garden City concept. With the establishment of a high-quality cluster group and the cultivation of each cluster therein, Yilan has created a healthy, prosperous, and characteristic town agglomeration. Its experiences and development model have great implications for the future construction of small and medium-sized towns in Chinese mainland.展开更多
Characteristic town has became an important carrier for urban-mral integration. Based on the multiple compounding of the charactemtic town planning, it is significant to combine tiie universal viewpoint widi tradit...Characteristic town has became an important carrier for urban-mral integration. Based on the multiple compounding of the charactemtic town planning, it is significant to combine tiie universal viewpoint widi traditional small town planning. This paper by combining with “universaT viewpoint introduced the transformation of traditional small town planning in theory and practice, and combed the planning stategies from the 4 a^ects of “all level”,“all space”, “all element^,and “all dimension”. Based on the master plan of Guzhu Town in Heyuan, specific strategies were put forward from the 6 dimensions of resoutce analysis, spatial layout, industtiai construction, traffic connection, ecological control and system update, to provide references for the planning of characteristic towns.展开更多
In recent years,Shenzhen's housing prices are very high,ranking top 3 in China,and the purchasing power of ordinary residents has been seriously insufficient,leading to increase in demand for security housing.At p...In recent years,Shenzhen's housing prices are very high,ranking top 3 in China,and the purchasing power of ordinary residents has been seriously insufficient,leading to increase in demand for security housing.At present,Shenzhen's security housing projects are concentrated in areas outside the former Special Economic Zones,such as Pingshan,Longgang and Longhua.The houses in Luohu,Futian and Nanshan districts,where obtaining housing is more difficult and the intention of living is the most concentrated are scarce.The community distance is too long for most commuters inside customs.In terms of spatial distribution,the structural contradiction between the supply and demand of security housing has become increasingly prominent.In this paper,the public housing policies in the United States and Singapore were studied,and their reference to the diversification of Shenzhen's security housing location was analyzed.In addition,a feasible housing policy was proposed for Shenzhen.展开更多
基金sponsored by the National Natural Science Foundation of China(Nos.11772261 and 11972305)Aeronautical Science Foundation of China(No.2016ZA53011)Foundation of National Key Laboratory(No.JCKYS2019607005).
文摘A variable-fidelity method can remarkably improve the efficiency of a design optimization based on a high-fidelity and expensive numerical simulation,with assistance of lower-fidelity and cheaper simulation(s).However,most existing works only incorporate‘‘two"levels of fidelity,and thus efficiency improvement is very limited.In order to reduce the number of high-fidelity simulations as many as possible,there is a strong need to extend it to three or more fidelities.This article proposes a novel variable-fidelity optimization approach with application to aerodynamic design.Its key ingredient is the theory and algorithm of a Multi-level Hierarchical Kriging(MHK),which is referred to as a surrogate model that can incorporate simulation data with arbitrary levels of fidelity.The high-fidelity model is defined as a CFD simulation using a fine grid and the lower-fidelity models are defined as the same CFD model but with coarser grids,which are determined through a grid convergence study.First,sampling shapes are selected for each level of fidelity via technique of Design of Experiments(DoE).Then,CFD simulations are conducted and the output data of varying fidelity is used to build initial MHK models for objective(e.g.C_D)and constraint(e.g.C_L,C_m)functions.Next,new samples are selected through infillsampling criteria and the surrogate models are repetitively updated until a global optimum is found.The proposed method is validated by analytical test cases and applied to aerodynamic shape optimization of a NACA0012 airfoil and an ONERA M6 wing in transonic flows.The results confirm that the proposed method can significantly improve the optimization efficiency and apparently outperforms the existing single-fidelity or two-level-fidelity method.
基金Project supported by the National Natural Science Foundation of China(Nos.90815001and11072064)Key Project of Guangxi Science and Technology Lab Center(No.LGZX201101)
文摘An experimental analysis on the subsequent yield-surfaces evolution using multiple specimens is presented for a 45 steel after a prescribed pre-strain loading in three different directions respectively, and the yielding is defined by a designated offsetting strain. The size of the subsequent yield surface is found smaller than the initial yield surface; the negative cross effects are observed in the normal loading direction, its shape is not a Mises circle but has a rather blunt nose in loading direction and flat in the opposite. These results strongly depend on the loading path and the prescribed offset plastic strain. The plastic flow direction to the subsequent yield surface is investigated, and it is found that the plastic flow direction deviates from the normal flow rule. The deviation differs from preloading case to preloading case. And the plastic flow direction would have a larger deviation from the normal of the yield surface, if the subsequent yield was defined by a smaller offset strain. Furthermore, the experiments are simulated using the Chaboche model, and the results show that it can rationally predict yield-surface only when yield is defined by a fairly large offset strain.
基金Project （11462002） supported by the National Natural Science Foundation of China Project （2016GXNSFAA380218） supported by Guangxi Natural Science Foundation, China+1 种基金 Project （2014ZDK002） supported by the Open Project of Guangxi Key Laboratory of Disaster Prevention and Structural Safety at Guangxi University, China and Project （Z01） supported by the Science Foundation for Doctorate Research of Guangxi University of Science and Technology, China.
文摘To investigate the relationship between macro-plastic behavior and meso-deformation mechanism of Mg alloy AZ31, the mathematical models for various deformation mechanisms of slip, twinning and detwinning are established, respectively. Furthermore, in order to capture the Bauschinger effect under cyclic loading, the back stress is introduced into the three independent deformation mechanisms, respectively. Finally, using the above-mentioned model, a new cyclic plastic constitutive model based on the constitutive theory of crystal deformation for magnesium alloy is established. On this basis, the numerical simulation for AZ31 under cyclic loading with the axial strain amplitude of 1.2% is carried out in accordance with the aforementioned crystal plas- ticity theory associated with the representative volume element model. The comparison between the stress-strain curves obtained from the simulation and the experiments shows that the macro- scopic mechanical responses predicted using the proposed model are in good agreement with the experimental results. In particular, the unique characteristics of cyclic macro-plastic behavior observed in the experiments can be satisfactorily captured by the presented crystal plasticity model. At the mesoscale, these features are caused by the alternate occurrence of twinning and detwinning mechanisms. The further analysis of meso-plastic behavior shows that there are het- erogeneous distributions of twinning, stress-strain and stress triaxiality in polycrystal under cyclic loading.
基金supported by the Ministry of Science and Technology of China(Grant Nos.2020SKA0110401,2020SKA0110402,and 2020SKA0110100)the National Key Research and Development Program of China(Grant Nos.2018YFA0404504,and 2018YFA0404601)+5 种基金the National Natural Science Foundation of China(Grant Nos.11890691,12205388,12220101003,12122301,12233001,and 12073088)the China Manned Space Project(Grant No.CMS-CSST-2021(A02,A03,A04,B01))the Major Key Project of PCLthe 111 project(Grant No.B20019)the Shanghai Natural Science Research Grant(Grant No.21ZR1430600)sponsorship from Yangyang Development Fund。
文摘Large-scale structure(LSS)surveys will increasingly provide stringent constraints on our cosmological models.Recently,the density-marked correlation function(MCF)has been introduced,offering an easily computable density-correlation statistic.Simulations have demonstrated that MCFs offer additional,independent constraints on cosmological models beyond the standard two-point correlation(2PCF).In this study,we apply MCFs for the first time to SDSS CMASS data,aiming to investigate the statistical information regarding clustering and anisotropy properties in the Universe and assess the performance of various weighting schemes in MCFs,and finally obtain constraints onΩ_(m).Upon analyzing the CMASS data,we observe that,by combining different weights(α=[-0.2,0,0.2,0.6]),the MCFs provide a tight and independent constraint on the cosmological parameterΩ_(m),yieldingΩ_(m)=0.293±0.006 at the 1σlevel,which represents a significant reduction in the statistical error by a factor of 3.4 compared to that from 2PCF.Our constraint is consistent with recent findings from the small-scale clustering of BOSS galaxies(Zhai et al.Astronphys.J.948,99(2023))within the 1σlevel.However,we also find that our estimate is lower than the Planck measurements by about 2.6σ,indicating the potential presence of new physics beyond the standard cosmological model if all the systematics are fully corrected.The method outlined in this study can be extended to other surveys and datasets,allowing for the constraint of other cosmological parameters.Additionally,it serves as a valuable tool for forthcoming emulator analysis on the Chinese Space Station Telescope(CSST).
基金funded by the National Natural Science Foundation of China(32060637 and 32260708)the Highlevel Talent Innovation and Entrepreneurship Funding Project in Guizhou Province,China((2021)01)+3 种基金the Guizhou Provincial Science and Technology Innovation Talent Team Project,China(Qian Ke He Pingtai RencaiCXTD(2021)004)the Systematic and Applied Acarology Society International Joint Project,England(2022(01))the Growth Project of Youth Talent in Ordinary Universities in Guizhou Province,China((2021)079)the Natural Science Special Project in Guizhou University,China((2020)02)。
文摘Parasitoids are key regulators in ecological communities and widely used as agents in biocontrol programmes.The fall armyworm,Spodoptera frugiperda,recently invaded multiple continents and caused substantial economic losses in agriculture.Pyemotes zhonghuajia,a newly identified mite parasitoid,has shown potential for controlling various agricultural insect pests.Therefore,this study tested the performance of P.zhonghuajia in parasitising S.frugiperda.We also investigated the sublethal effects of parasitism by P.zhonghuajia on host fitness traits,transgenerational impacts,and cellular and humoral immunity.Our result showed that the fifth-instar larvae of S.frugiperda parasitised by 40 P.zhonghuajia were all dead(i.e.,a lethal effect),while parasitism by 5 or 10 P.zhonghuajia was considered sublethal since many S.frugiperda survived to adulthood and produced offspring after mating.The sublethal influences from parasitism by P.zhonghuajia resulted in reduced pupal weight,adult emergence rate and fecundity,but increased developmental time and longevity.Parasitism at both lethal(40 mites)and sublethal(10 mites)levels impaired the cellular and humoral immunity of S.frugiperda.This study presents the first empirical evidence that mite parasitoids can negatively influence host immunity.Moreover,it provides insights into the biocontrol potential of mite parasitoids and their interactions with hosts.
基金supported by the National Natural Science Foundation of China(Nos.10902025 and 11072064)the Scientific Research Foundation of GuangXi University(No.XBZ100713)the Key Project of GuangXi Science and Technology Lab Center(No.LGZX201101)
文摘Based on the thermodynamic theory, an orthotropic damage constitutive model was developed to describe the nonlinear mechanical behavior of C/SiC composites. The different nonlinear kinematic and isotropic hardening functions were adopted to describe accurately the damage evolution processes. The damage variables were defined with the damaged modulus and the initial undamaged modulus on energy equivalence principle. The initial orthotropy and damage coupling were presented in the damage yield function. Tensile and in-plane shear loading and unloading tests were performed, and a good agreement between the model and the experimental results was achieved.
基金supported by the National Natural Science Foundation of China(92157202,32025010,32241002,92254301,32261160376,31970709,32070729,32100619,32170747,32322022,32370782,32371007,32300608,and 32300620)the National Key Research and Development Program of China(2022YFA1103800,2022YFE0210100,and 2019YFA0904500)+9 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(CAS)(XDB0480000)the Key Research Program,CAS(ZDBS-ZRKJZ-TLC003)the International Cooperation Program,CAS(154144KYSB20200006)the CAS Project for Young Scientists in Basic Research(YSBR-075)the Guangdong Provincial Science and Technology Program(2023B1111050005,2023A1515030231,2022A1515110493,2020B1212060052,2021A1515012513,2021B1515020096,2022A1515012616,and 2022A1515110951)the Guangzhou Science and Technology Program(202102021037,202102020827,202102080066,and 202206060002)the Open Research Program of Key Laboratory of Regenerative Biology,CAS(KLRB202106,KLRB202107,and KLRB202203)the CAS Youth Innovation Promotion Association(Y2021097 and 2021355)NSFC/RGC Joint Grant Scheme(N_CUHK 428/22)the Open Research Funds from the Sixth Affiliated Hospital of Guangzhou Medical University,Qingyuan People’s Hospital(202301-203)。
文摘Metabolites play important roles in numerous cell biology processes,such as cell proliferation,differentiation,stress response,and cell death[1].Recently,lactate and lactate-derived lysine residue lactylation(Kla)have emerged as newly discovered epigenetic modifications that play critical roles in various physiological and pathological processes.In the history of lactate research,we can categorize the studies into three mile stones(Fig.S1 online).
基金financially supported by the National Key Research and Development Program of China (2017YFA0106300)the Strategic Priority Research Program of the Chinese Academy of Sciences (XDA16030505)+6 种基金the National Natural Science Foundation projects of China (2017YFA0102900, 2019YFA09004500, 2017YFC1001602, 2016YFA0100300, 2018YFA0107100)the National Natural Science Foundation projects of China (92157202, 32025010, 31801168, 31900614, 31970709, 81901275, 32070729, 32100619, 32170747)the Key Research Program of Frontier Sciences, CAS (QYZDB-SSW-SMC001)International Cooperation Program (154144KYSB20200006)Guangdong Province Science and Technology Program (2020B1212060052, 2018A030313825, 2018GZR110103002, 2020A1515011200, 2020A1515010919, 2020A1515011410, 2021A1515012513)Guangzhou Science and Technology Program (201807010067, 202002030277, 202102021250, 202102020827, 202102080066), Open Research Program of Key Laboratory of Regenerative Biology, CAS (KLRB201907, KLRB202014)CAS Youth Innovation Promotion Association (to Y. W. and K. C.)
文摘Cell fate determination as a fundamental question in cell biology has been extensively studied at different regulatory levels for many years.However,the mechanisms of multilevel regulation of cell fate determination remain unclear.Recently,we have proposed an Epigenome-Metabolome-Epigenome(E-M-E)signaling cascade model to describe the cross-over cooperation during mouse somatic cell reprogramming.In this review,we summarize the broad roles of E-M-E signaling cascade in different cell biological processes,including cell differentiation and dedifferentiation,cell specialization,cell proliferation,and cell pathologic processes.Precise E-M-E signaling cascades are critical in these cell biological processes,and it is of worth to explore each step of E-M-E signaling cascade.E-M-E signaling cascade model sheds light on and may open a window to explore the mechanisms of multilevel regulation of cell biological processes.
基金Supported by the National Natural Science Foundation of China (Grant Nos. 10472092 and 10662001)the Aviation Science Foundation of China (Grant No. 04C53027)
文摘The tension necking of FCC copper single crystal specimen with a square cross section was analyzed under the slip deformation mechanism. The actual clamp manner of the specimen was modeled by setting correlative boundary condition,and the small angle deflection between tension loading axis and crystallography axis [100] was taken into account. The finite deformation numerical analysis of three-dimensional necking deformation for the specimen was performed by apply-ing crystal plasticity theory associated with a numerical algorithm suggested by the first author. According to the comparison with experimental observation,the fact was confirmed that the numerical results could describe the loading elongation curve of the copper single crystal specimen under large strain tension reasonably,and the method could be used to investigate the necking characteristic in neck shape and the effect due to the small angle deflection. Further,the investigation into the influence of specimen cross-section shape on necking was also performed;the results on mechanical response and neck profile evolution obtained through modeling of cylindrical specimen were compared with those obtained with square cross-section specimen.
基金the National Natural Science Foundation of China (Grant 51465002, 11262001, 51675110, 11632007)the Systematic Project of Guangxi Key Laboratory Project of Disaster Prevention and Engineering Safety (Grant 2016ZDX07).
文摘Based on the ABAQUS platform for finite element analysis, the extended finite element method (XFEM) considering elastoplastic constitutive relationship is developed, by which the displacement discontinuity across the crack surface and the strong nonlinearity near the crack tip can be described more accurately. The strip specimens with unilateral cracks and central cracks under uniaxial tension are simulated using the XFEM and the FEM, respectively. The J-integral across the crack on each incremen t is calcula ted using the equivale nt domain integral met hod (EDIM), the interaction integral met hod and the FEM, respectively. The effec ts of mesh size and mesh shape near the crack tip, element type and different calculation methods on the accuracy of J-integral are analyzed. The simulation results show that the XFEM is more accurate than the FEM with the same element size and type. The fracture tests of cast iron specimens with unilateral cracks under uniaxial tension are performed, and the J-integral criterion is valid to predict the fracture initiation in numerical simulation. The critical value of J-integral is calculated using the EDIM of the XFEM. The comparisons demonstrate that the simulated elastoplastic load-displacement curves with the XFEM are in good agreement with the experimental results.
文摘Taking the planning practice of green transportation in Sino-Singapore Tianjin Eco-city as an example,the key factors and design strategies for its healthy development were summarized from the aspects of the coordination of land use and traffic development,the development of the public transport plus slow traffic model,and the development of reasonable and humanized traffic management measures,through analyzing the connotation and scale of green cluster.In addition,the design strategies of the green transportation concept suitable for the development of urban clusters represented by Guangming New District in Shenzhen were proposed,so as to provide a reference for promoting better the coordinated development of green traffic and cities,and maximizing the economic,social and environmental benefits of green transportation development.
基金This study was supported in part by New Zealand Government core funding for Crown Research Institutes from the Ministry of Business,Innovation and Employment’s Science and Innovation Group.
文摘Kin recognition has been widely observed in various taxa.Cannibalism avoidance may be a strong driver for the evolution of kin recognition,as it may avoid a reduction in inclusive fitness.Kin recognition has recently been observed in a generalist phytoseiid,Amblyseius herbicolus(Acari:Phytoseiidae).This study experimentally examined the degree of relatedness needed between prey larvae and cannibal adults of A.herbicolus for the occurrence of kin discrimination.The adults were individually placed in enclosed arenas with two prey,a daughter and a more distant related larva,to observe their cannibalizing choice.The adults of A.herbicolus did not discriminate between close relatives(daughter versus niece)but preferably cannibalized more distant kin(i.e.,first and second cousins once removed).Phenotype matching and familiarization seem prominent as recognition mechanisms used by A.herbicolus adults.The effect of learning on kin recognition through prior contact in A.herbicolus requires further investigation.Studies on other adaptive functions of kin recognition of A.herbicolus,such as cooperation and parental care,may provide meaningful insights.
基金the National Natural Science Foundation of China(Nos.11632007 and 11472085)the Project of Promoting the Basic Ability of Scientific Research of Young and Middle-aged Teachers in Universities of Guangxi(No.2019KY1365),which are gratefully acknowledged.
文摘The investigation based on experiments and crystal plasticity simulation is carried out to undertake research on mesodeformation inhomogeneity of metals under cyclic loading at grain level.Symmetrical tension-compression cycle tests are performed on pure copper specimens to observe the inhomogeneous distribution of slip deformation and its evolution with cycle number.Cyclic hardening process and stable hysteretic behavior of pure copper under cyclic loading are simulated by applying a crystal plasticity constitutive model including nonlinear kinematic hardening associated with the polycrystalline representative volume element(RVE)constructed by Voronoi tessellation.Inhomogeneous deformation processes of materials under six different strain amplitudes are simulated by 1600 cycles,respectively.We discuss the variation law of the inhomogeneous meso-deformation distribution of material with the increase in cycle number,and research the rationality of characterizing the inhomogeneous deformation distribution and variation with the statistical standard deviation of the micro-longitudinal strain or the statistical average of the first principal strain based on the statistical analysis of the inhomogeneous deformation of the polycrystalline RVE model during the cycling process.It is found that these two parameters are related to and approximately inversely proportional to the length of measuring gauge.
文摘Located in Wutiao Harbor of Tainan City, Hai'an Road used to be a significant trade logistics center and the most flourishing commercial area until the construction of underground street in Hai'an Road and the beginning of broadening project which brought irreparable and huge damages to this historic street. Fortunately, Artistic Street Renovation Plan was implemented in 2004 and succeeded in revitalizing Hai'an Road. The implementation of this plan transformed this street into an art museum to which lots of photographers and artists were attracted and made a pilgrimage. Besides, it remodeled the local cultural identity and enhanced the community cohesion. Based on the in-depth research on the integral process of Artistic Street Renovation Plan on Hai'an Road, this paper focuses on the analysis of multivariate stakeholders' partnership among government, inhabitants, curatorial group and artists so as to propose protective methods and developmental ideas for historical streets.
文摘Dafen Oil Painting Village, the largest oil painting village in current China, takes cultural industries like creation and wholesale of oil paintings as the pillar. As one of the urban villages in Shenzhen, Dafen Village not only has the common characteristics of urban morphology as ordinary urban villages, but also has something unique. In this paper, study of the urban morphology of Dafen Oil Painting Village is mainly from 3 aspects: firstly, the formation of street space in Dafen Village; secondly, analysis of the status of urban morphology of Dafen Village; thirdly, the plane layout and public space of Dafen Village. In the end, this paper put forward some suggestions about the future development of urban morphology and space layout in Dafen Village.
基金supported by the National Key Research and Development Program of China(2018YFA0107100)the National Natural Science Foundation of China(Grant Nos.31622037and 31631163001).
文摘Pluripotent stem cells hold tremendous promise for regenerative medicine.The mechanisms underlying the acquisition and loss of pluripotency have been revealed at multiple levels.Subcellular mechanisms such as metabolic and organelle remodeling are emerging as critical for pluripotent cell fate transitions.Understanding the rules and roles of organelle remodeling will not only provide important insights into pluripotency regulation,but also help improving application in regenerative medicine.In this review,we summarize recent discoveries in organelle remodeling during the acquisition and loss of pluripotency and discuss how membrane lipids orchestrate organelle remodeling and drive nuclear gene expression.
文摘Yilan is a successful model of agricultural county transformation during Taiwan's rapid development period. Its urbanization can be considered as an application and evolution of the Garden City concept. With the establishment of a high-quality cluster group and the cultivation of each cluster therein, Yilan has created a healthy, prosperous, and characteristic town agglomeration. Its experiences and development model have great implications for the future construction of small and medium-sized towns in Chinese mainland.
文摘Characteristic town has became an important carrier for urban-mral integration. Based on the multiple compounding of the charactemtic town planning, it is significant to combine tiie universal viewpoint widi traditional small town planning. This paper by combining with “universaT viewpoint introduced the transformation of traditional small town planning in theory and practice, and combed the planning stategies from the 4 a^ects of “all level”,“all space”, “all element^,and “all dimension”. Based on the master plan of Guzhu Town in Heyuan, specific strategies were put forward from the 6 dimensions of resoutce analysis, spatial layout, industtiai construction, traffic connection, ecological control and system update, to provide references for the planning of characteristic towns.
文摘In recent years,Shenzhen's housing prices are very high,ranking top 3 in China,and the purchasing power of ordinary residents has been seriously insufficient,leading to increase in demand for security housing.At present,Shenzhen's security housing projects are concentrated in areas outside the former Special Economic Zones,such as Pingshan,Longgang and Longhua.The houses in Luohu,Futian and Nanshan districts,where obtaining housing is more difficult and the intention of living is the most concentrated are scarce.The community distance is too long for most commuters inside customs.In terms of spatial distribution,the structural contradiction between the supply and demand of security housing has become increasingly prominent.In this paper,the public housing policies in the United States and Singapore were studied,and their reference to the diversification of Shenzhen's security housing location was analyzed.In addition,a feasible housing policy was proposed for Shenzhen.
