In this paper,we discuss properties of SDSS J1042-0018 which is a broad line active galactic nucleus(AGN)but misclassified as an H II galaxy in the BPT diagram(SDSS J1042-0018 is called a misclassified broad line AGN)...In this paper,we discuss properties of SDSS J1042-0018 which is a broad line active galactic nucleus(AGN)but misclassified as an H II galaxy in the BPT diagram(SDSS J1042-0018 is called a misclassified broad line AGN).The emission lines around Hαand around Hβare well described by different model functions,considering broad Balmer lines to be described by Gaussian or Lorentz functions.Different model functions lead to different determined narrow emission line fiuxes,but the different narrow emission line fiux ratios lead SDSS J1042-0018 as an H II galaxy in the BPT diagram.In order to explain the unique properties of the misclassified broad line AGN SDSS J1042-0018,two methods are proposed,the star-forming contributions and the compressed narrow emission line regions with high electron densities near to critical densities of forbidden emission lines.Fortunately,the strong star-forming contributions can be preferred in SDSS J1042-0018.The misclassified broad line AGN SDSS J1042-0018,well explained by star-forming contributions,could provide further clues on the applications of BPT diagrams to the normal broad line AGNs.展开更多
Objectives:Spinal fusion is a widely employed treatment of patients with degenerative disc disease,in which a cage is used to replace the disc for spinal fusion.But it often fails for insufficient mechanical strength ...Objectives:Spinal fusion is a widely employed treatment of patients with degenerative disc disease,in which a cage is used to replace the disc for spinal fusion.But it often fails for insufficient mechanical strength and poor osseointegration.Here,we designed a polyether-ether-ketone(PEEK)/tantalum(Ta)composite cage with a biomimetic gradient porous micro-structure,simultaneously enhancing mechanical properties and accelerating osseointegration in spinal fusion.Materials and methods:In the study,based on the mechanical performances of PEEK and osteogenic potential of Ta,and the three-dimensional(3D)structures of cuttlebone and vertebra,the cages were respectively 3D printed by pure PEEK,PEEK with 5 wt%Ta(PEEK/Ta-5),PEEK with 10 wt%Ta(PEEK/Ta-10)and PEEK with 15 wt%Ta(PEEK/Ta-15),then verified<i>in vitro</i>and in sheep cervical fusion model systematically.Results:Vertebral Gyroid structure PEEK/Ta-15 cage exhibited superior mechanical properties than Cuttlebone-like structure PEEK/Ta-15 cage,closer to the cervical vertebra.Furthermore,PEEK/Ta-15 cage with higher Ta microparticles in PEEK provided a biomimetic gradient porous micro-structure with higher surface energy,guiding cell biological behavior,promoting new bone penetration,and accelerating osseointegration<i>in vivo</i>.Conclusion:In conclusion,the study designed a biomimetic gradient porous cage with a micro-structure for enhancing mechanical properties,accelerating osseointegration and forming an anatomical lock in the fusion segment through composites,mechanical efficiency,surface extension,and pores.展开更多
The developments of tough hydrogels in recent years have greatly expanded the applications of hydrogels as structural materials. However, most of the tough hydrogels are made of synthetic polymers. To develop biopolym...The developments of tough hydrogels in recent years have greatly expanded the applications of hydrogels as structural materials. However, most of the tough hydrogels are made of synthetic polymers. To develop biopolymer-based tough hydrogels has both fundamental and practical significances. Here we report a series of polysaccharides-based tough hydrogel films prepared by polyion complexation and solvent evaporation of chondroitin sulfate（CS） and protonated chitosan（CHT） solutions with different weight ratios. The obtained CS/CHT gel films with thickness of 40-80 μm and water content of 66 wt%-81 wt% possess excellent mechanical properties, with tensile breaking stress and breaking strain being 0.4-3 MPa and 160%-320%, respectively. We found that in the mixture solutions there are large amounts of excess CHT in terms of charges; after swelling the films in water, the acetic acid, which is used to protonate the amino groups of CHT, diffuses out of the gel matrix, enhancing the intermolecular interactions between CHT molecules and thus improving the mechanical properties of gel films, besides the ionic bonds between CS and CHT. Antimicrobial tests also showed that the gel films with low weight ratio of CS to CHT, corresponding to the case with excess CHT, have evident antimicrobial effect. These CS/CHT gel films with good mechanical properties and antimicrobial effect should extend the applications of hydrogels in biomedical fields.展开更多
基金the kind support of Starting Research Fund of Nanjing Normal Universitythe kind support of NSFC-12173020the kind support of Da Chuang project of Nanjing Normal University for undergraduate students。
文摘In this paper,we discuss properties of SDSS J1042-0018 which is a broad line active galactic nucleus(AGN)but misclassified as an H II galaxy in the BPT diagram(SDSS J1042-0018 is called a misclassified broad line AGN).The emission lines around Hαand around Hβare well described by different model functions,considering broad Balmer lines to be described by Gaussian or Lorentz functions.Different model functions lead to different determined narrow emission line fiuxes,but the different narrow emission line fiux ratios lead SDSS J1042-0018 as an H II galaxy in the BPT diagram.In order to explain the unique properties of the misclassified broad line AGN SDSS J1042-0018,two methods are proposed,the star-forming contributions and the compressed narrow emission line regions with high electron densities near to critical densities of forbidden emission lines.Fortunately,the strong star-forming contributions can be preferred in SDSS J1042-0018.The misclassified broad line AGN SDSS J1042-0018,well explained by star-forming contributions,could provide further clues on the applications of BPT diagrams to the normal broad line AGNs.
文摘Objectives:Spinal fusion is a widely employed treatment of patients with degenerative disc disease,in which a cage is used to replace the disc for spinal fusion.But it often fails for insufficient mechanical strength and poor osseointegration.Here,we designed a polyether-ether-ketone(PEEK)/tantalum(Ta)composite cage with a biomimetic gradient porous micro-structure,simultaneously enhancing mechanical properties and accelerating osseointegration in spinal fusion.Materials and methods:In the study,based on the mechanical performances of PEEK and osteogenic potential of Ta,and the three-dimensional(3D)structures of cuttlebone and vertebra,the cages were respectively 3D printed by pure PEEK,PEEK with 5 wt%Ta(PEEK/Ta-5),PEEK with 10 wt%Ta(PEEK/Ta-10)and PEEK with 15 wt%Ta(PEEK/Ta-15),then verified<i>in vitro</i>and in sheep cervical fusion model systematically.Results:Vertebral Gyroid structure PEEK/Ta-15 cage exhibited superior mechanical properties than Cuttlebone-like structure PEEK/Ta-15 cage,closer to the cervical vertebra.Furthermore,PEEK/Ta-15 cage with higher Ta microparticles in PEEK provided a biomimetic gradient porous micro-structure with higher surface energy,guiding cell biological behavior,promoting new bone penetration,and accelerating osseointegration<i>in vivo</i>.Conclusion:In conclusion,the study designed a biomimetic gradient porous cage with a micro-structure for enhancing mechanical properties,accelerating osseointegration and forming an anatomical lock in the fusion segment through composites,mechanical efficiency,surface extension,and pores.
基金financially supported by the National Natural Science Foundation of China(No.51403184)Scientific Research Foundation for the Returned Overseas Chinese Scholars(No.J20141135)Fundamental Research Funds for the Central Universities of China
文摘The developments of tough hydrogels in recent years have greatly expanded the applications of hydrogels as structural materials. However, most of the tough hydrogels are made of synthetic polymers. To develop biopolymer-based tough hydrogels has both fundamental and practical significances. Here we report a series of polysaccharides-based tough hydrogel films prepared by polyion complexation and solvent evaporation of chondroitin sulfate（CS） and protonated chitosan（CHT） solutions with different weight ratios. The obtained CS/CHT gel films with thickness of 40-80 μm and water content of 66 wt%-81 wt% possess excellent mechanical properties, with tensile breaking stress and breaking strain being 0.4-3 MPa and 160%-320%, respectively. We found that in the mixture solutions there are large amounts of excess CHT in terms of charges; after swelling the films in water, the acetic acid, which is used to protonate the amino groups of CHT, diffuses out of the gel matrix, enhancing the intermolecular interactions between CHT molecules and thus improving the mechanical properties of gel films, besides the ionic bonds between CS and CHT. Antimicrobial tests also showed that the gel films with low weight ratio of CS to CHT, corresponding to the case with excess CHT, have evident antimicrobial effect. These CS/CHT gel films with good mechanical properties and antimicrobial effect should extend the applications of hydrogels in biomedical fields.
