The tilted implant with immediate function is increasingly used in clinical dental therapy for edentulous and partially edentulous patients with excessive bone resorption and the anatomic limitations in the alveolar r...The tilted implant with immediate function is increasingly used in clinical dental therapy for edentulous and partially edentulous patients with excessive bone resorption and the anatomic limitations in the alveolar ridge.However,peri-implant cervical bone loss can be caused by the stress shielding effect.Herein,inspired by the concept of“materiobiology”,the mechanical characteristics of materials were considered along with bone biology for tilted implant design.In this study,a novel Ti-35Nb-2Ta-3Zr alloy(TNTZ)implant with low elastic modulus,high strength and favorable biocompatibility was developed.Then the human alveolar bone environment was mimicked in goat and finite element(FE)models to investigate the mechanical property and the related peri-implant bone remodeling of TNTZ compared to commonly used Ti-6Al-4V(TC4)in tilted implantation under loading condition.Next,a layer-by-layer quantitative correlation of the FE and X-ray Microscopy(XRM)analysis suggested that the TNTZ implant present better mechanobiological characteristics including improved load transduction and increased bone area in the tilted implantation model compared to TC4 implant,especially in the upper 1/3 region of peri-implant bone that is“lower stress”.Finally,combining the static and dynamic parameters of bone,it was further verified that TNTZ enhanced bone remodeling in“lower stress”upper 1/3 region.This study demonstrates that TNTZ is a mechanobiological optimized tilted implant material that enhances load transduction and bone remodeling.展开更多
Pixel image lag in a 4-T CMOS image sensor is analyzed and simulated in a two-dimensional model.Strategies of reducing image lag are discussed from transfer gate channel threshold voltage doping adjustment,PPD N-type ...Pixel image lag in a 4-T CMOS image sensor is analyzed and simulated in a two-dimensional model.Strategies of reducing image lag are discussed from transfer gate channel threshold voltage doping adjustment,PPD N-type doping dose/implant tilt adjustment and transfer gate operation voltage adjustment for signal electron transfer.With the computer analysis tool ISE-TCAD,simulation results show that minimum image lag can be obtained at a pinned photodiode n-type doping dose of 7.0×10^12 cm^-2,an implant tilt of -2°,a transfer gate channel doping dose of 3.0×10^12 cm^-2 and an operation voltage of 3.4 V.The conclusions of this theoretical analysis can be a guideline for pixel design to improve the performance of 4-T CMOS image sensors.展开更多
基金supported by the National Natural Science Foundation of China[grant number 52171075,51831011,U2032124]the Medical Engineering Cross Key Research Foundation of the Shanghai Jiao Tong University[grant number YG2017ZD06]+1 种基金the Science and Technology Commission of Shanghai Municipality[grant number 201409006300]the Opening Project of Shanghai Key Laboratory of Orthopaedic Implant[grant number KFKT2021001].
文摘The tilted implant with immediate function is increasingly used in clinical dental therapy for edentulous and partially edentulous patients with excessive bone resorption and the anatomic limitations in the alveolar ridge.However,peri-implant cervical bone loss can be caused by the stress shielding effect.Herein,inspired by the concept of“materiobiology”,the mechanical characteristics of materials were considered along with bone biology for tilted implant design.In this study,a novel Ti-35Nb-2Ta-3Zr alloy(TNTZ)implant with low elastic modulus,high strength and favorable biocompatibility was developed.Then the human alveolar bone environment was mimicked in goat and finite element(FE)models to investigate the mechanical property and the related peri-implant bone remodeling of TNTZ compared to commonly used Ti-6Al-4V(TC4)in tilted implantation under loading condition.Next,a layer-by-layer quantitative correlation of the FE and X-ray Microscopy(XRM)analysis suggested that the TNTZ implant present better mechanobiological characteristics including improved load transduction and increased bone area in the tilted implantation model compared to TC4 implant,especially in the upper 1/3 region of peri-implant bone that is“lower stress”.Finally,combining the static and dynamic parameters of bone,it was further verified that TNTZ enhanced bone remodeling in“lower stress”upper 1/3 region.This study demonstrates that TNTZ is a mechanobiological optimized tilted implant material that enhances load transduction and bone remodeling.
基金supported by the National Natural Science Foundation of China(Nos.60806010,60976030)the Tianjin Innovation Special Funds for science and Technology,China(No.05FZZDGX00200)
文摘Pixel image lag in a 4-T CMOS image sensor is analyzed and simulated in a two-dimensional model.Strategies of reducing image lag are discussed from transfer gate channel threshold voltage doping adjustment,PPD N-type doping dose/implant tilt adjustment and transfer gate operation voltage adjustment for signal electron transfer.With the computer analysis tool ISE-TCAD,simulation results show that minimum image lag can be obtained at a pinned photodiode n-type doping dose of 7.0×10^12 cm^-2,an implant tilt of -2°,a transfer gate channel doping dose of 3.0×10^12 cm^-2 and an operation voltage of 3.4 V.The conclusions of this theoretical analysis can be a guideline for pixel design to improve the performance of 4-T CMOS image sensors.