Additive manufacturing technology,by manipulating and emulating inherent multiscale,multi-material,and multifunctional structures found in nature,has created new opportunities for constructing heterogeneous structures...Additive manufacturing technology,by manipulating and emulating inherent multiscale,multi-material,and multifunctional structures found in nature,has created new opportunities for constructing heterogeneous structures associated with special properties and achieving ultra-high mechanical performance and reliability in ceramic composite materials.In this study,we have developed an innovative fabrication method designated as coaxial 3D printing for the synchronous construction of two constituents into ceramic composites with a tooth enamel biomimetic microstructure.Herein,the stiff silicate and flexible epoxy served as a strengthening bridge and toughening layer,respectively.The method differed from the traditional approach of randomly dispersing reinforcing components within a ceramic matrix.It allowed for the direct creation of an internally effective three-dimensional reinforcement network structure in ceramic composites.This process facilitated synergistic deformation and simultaneous enhancement of multiple materials and hierarchical structures.Owing to the uniform distribution of internal stress and effective block of microcrack propagation,the biomimetically structured silicate/epoxy ceramic composite has demonstrated much significant enhancement in mechanical properties,includingcompressive strength(48.8±3.12MPa),flexuralstrength(10.39±1.23MPa),andflexuraltoughness(218.7±54.6kJ/m^(3)),which was 0.5,2.1,and 47.5 times as high as those of the intrinsic brittle silicate ceramics,respectively.In-situ characterization and multiscale finite element simulation of microstructural evolution during three-point bending deformation further validated multiple-step features of the fracture process(silicate bridge fracture,interface detachment,epoxy extraction,and rupture),which benefited from interpenetrating structural features achieved by coaxial printing to accomplish with the complex propagating routines of the crack deflection in silicate ceramic composites.This coaxial 3D printing method paves the way for tailor展开更多
For each real number x∈(0,1),let[a_(1)(x),a_(2)(x),…,a_n(x),…]denote its continued fraction expansion.We study the convergence exponent defined byτ(x)=inf{s≥0:∞∑n=1(a_(n)(x)a_(n+1)(x))^(-s)<∞},which reflect...For each real number x∈(0,1),let[a_(1)(x),a_(2)(x),…,a_n(x),…]denote its continued fraction expansion.We study the convergence exponent defined byτ(x)=inf{s≥0:∞∑n=1(a_(n)(x)a_(n+1)(x))^(-s)<∞},which reflects the growth rate of the product of two consecutive partial quotients.As a main result,the Hausdorff dimensions of the level sets ofτ(x)are determined.展开更多
Chrysanthemum(Chrysanthemum morifolium)is one of the four major cut-flower plants worldwide and possesses both high ornamental value and cultural connotation.As most chrysanthemum varieties flower in autumn,it is cost...Chrysanthemum(Chrysanthemum morifolium)is one of the four major cut-flower plants worldwide and possesses both high ornamental value and cultural connotation.As most chrysanthemum varieties flower in autumn,it is costly to achieve annual production.JAZ genes in the TIFY family are core components of the jasmonic acid(JA)signaling pathway;in addition to playing a pivotal role in plant responses to defense,they are also widely implicated in regulating plant development processes.Here,we characterized the TIFY family gene CmJAZ1-like from the chrysanthemum cultivar‘Jinba’.CmJAZ1-like localizes in the nucleus and has no transcriptional activity in yeast.Tissue expression pattern analysis indicated that CmJAZ1-like was most active in the root and shoot apex.Overexpressing CmJAZ1-like with Jas domain deletion in chrysanthemum resulted in late flowering.RNA-Seq analysis of the overexpression lines revealed some differentially expressed genes(DEGs)involved in flowering,such as the homologs of the flowering integrators FT and SOC1,an FUL homolog involved in flower meristem identity,AP2 domain-containing transcription factors,MADS box genes,and autonomous pathway-related genes.Based on KEGG pathway enrichment analysis,the differentially transcribed genes were enriched in carbohydrate metabolic and fatty acid-related pathways,which are notable for their role in flowering in plants.This study preliminarily verified the function of CmJAZ1-like in chrysanthemum flowering,and the results can be used in molecular breeding programs aimed at flowering time regulation of chrysanthemum.展开更多
Let x∈(0,1)be a real number with continued fraction expansion[a_(1)(x),a_(2)(x),a_(3)(x),⋯].This paper is concerned with the multifractal spectrum of the convergence exponent of{a_(n)(x)}_(n≥1) defined by τ(x):=in...Let x∈(0,1)be a real number with continued fraction expansion[a_(1)(x),a_(2)(x),a_(3)(x),⋯].This paper is concerned with the multifractal spectrum of the convergence exponent of{a_(n)(x)}_(n≥1) defined by τ(x):=inf{s≥0:∑n≥1an^(-s)(x)<∞}.展开更多
目的比较改良脾-肺固定术与断流术治疗肝硬化门静脉高压症的临床疗效。方法回顾性分析2011年1月至2015年12月在郑州大学第一附属医院行手术治疗的60例肝硬化门静脉高压症患者临床资料。患者均签署知情同意书,符合医学伦理学规定。根据...目的比较改良脾-肺固定术与断流术治疗肝硬化门静脉高压症的临床疗效。方法回顾性分析2011年1月至2015年12月在郑州大学第一附属医院行手术治疗的60例肝硬化门静脉高压症患者临床资料。患者均签署知情同意书,符合医学伦理学规定。根据手术方式将患者分为改良脾-肺固定组和脾切除+断流术组(断流组)。其中改良脾-肺固定组26例,男18例,女8例,平均年龄(41±9)岁;断流组34例,男22例,女12例;年龄(44±8)岁。两组患者术后血细胞、门静脉压力比较采用t检验,并发症发生率比较采用χ~2检验。结果改良脾-肺固定组术后1年自由门静脉压力为(32.6±1.8)cm H_2O(1 cm H2O=0.098 k Pa),明显高于断流组的(29.9±2.3)cm H2O(t=4.963,P<0.05);WBC、Hb、Plt分别为(4.1±1.5)×10~9/L、(101±18)g/L、(102±40)×10~9/L,明显低于断流组的(5.8±1.9)×10~9/L、(113±16)g/L、(220±70)×10~9/L(t=-3.798,-2.588,-8.218;P<0.05);门静脉血栓形成率为8%(2/26),明显低于断流组的29%(10/34)(χ~2=4.344,P<0.05)。改良脾-肺固定组和断流组的上消化道出血率、肝性脑病发生率分别为15%(4/26)、4%(1/26)和9%(3/34)、9%(3/34),差异无统计学意义(χ~2=0.143,0.059;P>0.05)。结论与断流术相比,改良脾-肺固定术防治上消化道出血和肝性脑病疗效相似,且具有术后门静脉血栓发生率较低、保留部分脾脏功能和较高的门静脉压力利于肝脏灌注的优势。展开更多
基金the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB 0470303)the Fund of Natural Science Foundation of China(No.52073132)the Fundamental Research Funds for the Central Universities(Nos.zujbky-2022-ey02 and Izujbky-2023-eyt03).
文摘Additive manufacturing technology,by manipulating and emulating inherent multiscale,multi-material,and multifunctional structures found in nature,has created new opportunities for constructing heterogeneous structures associated with special properties and achieving ultra-high mechanical performance and reliability in ceramic composite materials.In this study,we have developed an innovative fabrication method designated as coaxial 3D printing for the synchronous construction of two constituents into ceramic composites with a tooth enamel biomimetic microstructure.Herein,the stiff silicate and flexible epoxy served as a strengthening bridge and toughening layer,respectively.The method differed from the traditional approach of randomly dispersing reinforcing components within a ceramic matrix.It allowed for the direct creation of an internally effective three-dimensional reinforcement network structure in ceramic composites.This process facilitated synergistic deformation and simultaneous enhancement of multiple materials and hierarchical structures.Owing to the uniform distribution of internal stress and effective block of microcrack propagation,the biomimetically structured silicate/epoxy ceramic composite has demonstrated much significant enhancement in mechanical properties,includingcompressive strength(48.8±3.12MPa),flexuralstrength(10.39±1.23MPa),andflexuraltoughness(218.7±54.6kJ/m^(3)),which was 0.5,2.1,and 47.5 times as high as those of the intrinsic brittle silicate ceramics,respectively.In-situ characterization and multiscale finite element simulation of microstructural evolution during three-point bending deformation further validated multiple-step features of the fracture process(silicate bridge fracture,interface detachment,epoxy extraction,and rupture),which benefited from interpenetrating structural features achieved by coaxial printing to accomplish with the complex propagating routines of the crack deflection in silicate ceramic composites.This coaxial 3D printing method paves the way for tailor
基金supported by the Scientific Research Fund of Hunan Provincial Education Department(21B0070)the Natural Science Foundation of Jiangsu Province(BK20231452)+1 种基金the Fundamental Research Funds for the Central Universities(30922010809)the National Natural Science Foundation of China(11801591,11971195,12071171,12171107,12201207,12371072)。
文摘For each real number x∈(0,1),let[a_(1)(x),a_(2)(x),…,a_n(x),…]denote its continued fraction expansion.We study the convergence exponent defined byτ(x)=inf{s≥0:∞∑n=1(a_(n)(x)a_(n+1)(x))^(-s)<∞},which reflects the growth rate of the product of two consecutive partial quotients.As a main result,the Hausdorff dimensions of the level sets ofτ(x)are determined.
基金the National Key Research and Development Program of China(2018YFD1000400)the National Natural Science Foundation of China(31930100,31701959)a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Chrysanthemum(Chrysanthemum morifolium)is one of the four major cut-flower plants worldwide and possesses both high ornamental value and cultural connotation.As most chrysanthemum varieties flower in autumn,it is costly to achieve annual production.JAZ genes in the TIFY family are core components of the jasmonic acid(JA)signaling pathway;in addition to playing a pivotal role in plant responses to defense,they are also widely implicated in regulating plant development processes.Here,we characterized the TIFY family gene CmJAZ1-like from the chrysanthemum cultivar‘Jinba’.CmJAZ1-like localizes in the nucleus and has no transcriptional activity in yeast.Tissue expression pattern analysis indicated that CmJAZ1-like was most active in the root and shoot apex.Overexpressing CmJAZ1-like with Jas domain deletion in chrysanthemum resulted in late flowering.RNA-Seq analysis of the overexpression lines revealed some differentially expressed genes(DEGs)involved in flowering,such as the homologs of the flowering integrators FT and SOC1,an FUL homolog involved in flower meristem identity,AP2 domain-containing transcription factors,MADS box genes,and autonomous pathway-related genes.Based on KEGG pathway enrichment analysis,the differentially transcribed genes were enriched in carbohydrate metabolic and fatty acid-related pathways,which are notable for their role in flowering in plants.This study preliminarily verified the function of CmJAZ1-like in chrysanthemum flowering,and the results can be used in molecular breeding programs aimed at flowering time regulation of chrysanthemum.
基金This research was supported by National Natural Science Foundation of China(11771153,11801591,11971195,12171107)Guangdong Natural Science Foundation(2018B0303110005)+1 种基金Guangdong Basic and Applied Basic Research Foundation(2021A1515010056)Kunkun Song would like to thank China Scholarship Council(CSC)for financial support(201806270091).
文摘Let x∈(0,1)be a real number with continued fraction expansion[a_(1)(x),a_(2)(x),a_(3)(x),⋯].This paper is concerned with the multifractal spectrum of the convergence exponent of{a_(n)(x)}_(n≥1) defined by τ(x):=inf{s≥0:∑n≥1an^(-s)(x)<∞}.
文摘目的比较改良脾-肺固定术与断流术治疗肝硬化门静脉高压症的临床疗效。方法回顾性分析2011年1月至2015年12月在郑州大学第一附属医院行手术治疗的60例肝硬化门静脉高压症患者临床资料。患者均签署知情同意书,符合医学伦理学规定。根据手术方式将患者分为改良脾-肺固定组和脾切除+断流术组(断流组)。其中改良脾-肺固定组26例,男18例,女8例,平均年龄(41±9)岁;断流组34例,男22例,女12例;年龄(44±8)岁。两组患者术后血细胞、门静脉压力比较采用t检验,并发症发生率比较采用χ~2检验。结果改良脾-肺固定组术后1年自由门静脉压力为(32.6±1.8)cm H_2O(1 cm H2O=0.098 k Pa),明显高于断流组的(29.9±2.3)cm H2O(t=4.963,P<0.05);WBC、Hb、Plt分别为(4.1±1.5)×10~9/L、(101±18)g/L、(102±40)×10~9/L,明显低于断流组的(5.8±1.9)×10~9/L、(113±16)g/L、(220±70)×10~9/L(t=-3.798,-2.588,-8.218;P<0.05);门静脉血栓形成率为8%(2/26),明显低于断流组的29%(10/34)(χ~2=4.344,P<0.05)。改良脾-肺固定组和断流组的上消化道出血率、肝性脑病发生率分别为15%(4/26)、4%(1/26)和9%(3/34)、9%(3/34),差异无统计学意义(χ~2=0.143,0.059;P>0.05)。结论与断流术相比,改良脾-肺固定术防治上消化道出血和肝性脑病疗效相似,且具有术后门静脉血栓发生率较低、保留部分脾脏功能和较高的门静脉压力利于肝脏灌注的优势。