This study aimed to develop a novel surgery classification for an endoscopic approach to middle ear cholesteatoma.We retrospectively analyzed the surgical approaches and outcomes of patients with middle ear cholesteat...This study aimed to develop a novel surgery classification for an endoscopic approach to middle ear cholesteatoma.We retrospectively analyzed the surgical approaches and outcomes of patients with middle ear cholesteatoma.Middle ear cholesteatoma surgeries were divided into four types and two special types as follows:type I,attic retraction pocket,which only requires tympanostomy tube placement or retraction pocket resection and cartilage reconstruction;typeⅡ,cholesteatoma which is limited to the attic or in which endoscopy can confirm complete removal of mastoid cholesteatoma lesions,including type Ⅱa,requiring only use of a curette,and type Ⅱ b,requiring use of an electric drill or chisel;type Ⅲ,cholesteatoma not limited to the attic,in which endoscopy cannot confirm complete removal of mastoid cholesteatoma lesions,requiring the combined use of endoscope and microscope to perform endoscopic tympanoplasty and"Canal Wall Up"mastoidectomy;type Ⅳ,extensive involvement of mastoid cavity cholesteatoma lesions and/or cases with a potential risk of complications,removal of which can only be performed under a microscope for"Canal Wall Down"mastoidectomy.In addition,there were two special types:"difficult external auditory canal"and congenital cholesteatoma in children.In our system,type I and type U middle ear cholesteatoma surgery was completely performed under an endoscope alone.However,estimating the extent of the lesions,determining the choice of mastoid opening and reestablishing ventilation are the key points for an endoscopic approach to middle ear cholesteatoma.The classification of endoscopic middle ear cholesteatoma surgery may benefit the selection of surgical indications.展开更多
First-principles calculations for several aromatic molecules with anhydride and thio groups on Ag(111) and Au(111)reveal that the self-assembly structures and the interface properties are mainly determined by the func...First-principles calculations for several aromatic molecules with anhydride and thio groups on Ag(111) and Au(111)reveal that the self-assembly structures and the interface properties are mainly determined by the functional groups of aromatic molecules. Detailed investigations of the electronic structures show that the electrons in molecular backbone are redistributed and charge transfer occurs through the bond between the metal and the functional groups after these molecules have been deposited on a metal substrate. The interaction between Ag(111)(or Au(111)) and aromatic molecules with anhydride functional groups strengthens the π bonds in the molecular backbone, while that between Ag(111)(or Au(111))and aromatic molecules with sulfur weakens the π bonds. However, the intrinsic electronic structures of the molecules are mostly conserved. The large-sized aromatic backbone has less influence on the nature of electronic structures than the small-sized one, either at the interface or at the molecules. These results are useful to build the good metal-molecule contact in molecule-based devices.展开更多
Large-area and flexible reduced graphene oxide(rGO)/Fe3O4 NPs/polyurethane(PU) composite films are fabricated by a facile solution-processable method. The monolayer assembly of Fe3O4 nanoparticles with a high particle...Large-area and flexible reduced graphene oxide(rGO)/Fe3O4 NPs/polyurethane(PU) composite films are fabricated by a facile solution-processable method. The monolayer assembly of Fe3O4 nanoparticles with a high particle-stacking density on the graphene oxide(GO) sheets is achieved by mixing two immiscible solutions of Fe3O4 nanoparticles in hexane and GO in dimethylformide(DMF) by a mild sonication. The x-ray diffraction and Raman spectrum confirm the reduced process of rGO by a simple thermal treatment. The permittivity value of the composite in a frequency range of 0.1 GHz-18 GHz increases with annealing temperature of GO increasing. For 5-wt% rGO/Fe3O4 NPs/PU, the maximum refection loss(RL) of over-35 dB appears at 4.5 GHz when the thickness of film increases to 5 mm. The rGO/Fe3O4 NPs/PU film, exhibiting good electromagnetic properties over GHz frequency range, could be a potential candidate as one of microwave absorption materials in flexible electronic devices.展开更多
基金the Fundamental Research Funds for the Central Universities(No.2019kfyXKJC039).
文摘This study aimed to develop a novel surgery classification for an endoscopic approach to middle ear cholesteatoma.We retrospectively analyzed the surgical approaches and outcomes of patients with middle ear cholesteatoma.Middle ear cholesteatoma surgeries were divided into four types and two special types as follows:type I,attic retraction pocket,which only requires tympanostomy tube placement or retraction pocket resection and cartilage reconstruction;typeⅡ,cholesteatoma which is limited to the attic or in which endoscopy can confirm complete removal of mastoid cholesteatoma lesions,including type Ⅱa,requiring only use of a curette,and type Ⅱ b,requiring use of an electric drill or chisel;type Ⅲ,cholesteatoma not limited to the attic,in which endoscopy cannot confirm complete removal of mastoid cholesteatoma lesions,requiring the combined use of endoscope and microscope to perform endoscopic tympanoplasty and"Canal Wall Up"mastoidectomy;type Ⅳ,extensive involvement of mastoid cavity cholesteatoma lesions and/or cases with a potential risk of complications,removal of which can only be performed under a microscope for"Canal Wall Down"mastoidectomy.In addition,there were two special types:"difficult external auditory canal"and congenital cholesteatoma in children.In our system,type I and type U middle ear cholesteatoma surgery was completely performed under an endoscope alone.However,estimating the extent of the lesions,determining the choice of mastoid opening and reestablishing ventilation are the key points for an endoscopic approach to middle ear cholesteatoma.The classification of endoscopic middle ear cholesteatoma surgery may benefit the selection of surgical indications.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.51471185 and 51325204)the National Key Research and Development Program of China(Grant No.2016YFJC020013)the National Supercomputing Center in Tianjin
文摘First-principles calculations for several aromatic molecules with anhydride and thio groups on Ag(111) and Au(111)reveal that the self-assembly structures and the interface properties are mainly determined by the functional groups of aromatic molecules. Detailed investigations of the electronic structures show that the electrons in molecular backbone are redistributed and charge transfer occurs through the bond between the metal and the functional groups after these molecules have been deposited on a metal substrate. The interaction between Ag(111)(or Au(111)) and aromatic molecules with anhydride functional groups strengthens the π bonds in the molecular backbone, while that between Ag(111)(or Au(111))and aromatic molecules with sulfur weakens the π bonds. However, the intrinsic electronic structures of the molecules are mostly conserved. The large-sized aromatic backbone has less influence on the nature of electronic structures than the small-sized one, either at the interface or at the molecules. These results are useful to build the good metal-molecule contact in molecule-based devices.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11274370,51471185,and 11704288)the National Key Research and Development Program of China(Grant Nos.2016YFJC020013 and 2018FYA0305800)
文摘Large-area and flexible reduced graphene oxide(rGO)/Fe3O4 NPs/polyurethane(PU) composite films are fabricated by a facile solution-processable method. The monolayer assembly of Fe3O4 nanoparticles with a high particle-stacking density on the graphene oxide(GO) sheets is achieved by mixing two immiscible solutions of Fe3O4 nanoparticles in hexane and GO in dimethylformide(DMF) by a mild sonication. The x-ray diffraction and Raman spectrum confirm the reduced process of rGO by a simple thermal treatment. The permittivity value of the composite in a frequency range of 0.1 GHz-18 GHz increases with annealing temperature of GO increasing. For 5-wt% rGO/Fe3O4 NPs/PU, the maximum refection loss(RL) of over-35 dB appears at 4.5 GHz when the thickness of film increases to 5 mm. The rGO/Fe3O4 NPs/PU film, exhibiting good electromagnetic properties over GHz frequency range, could be a potential candidate as one of microwave absorption materials in flexible electronic devices.