Ischemic stroke(IS)represents a significant threat to brain health due to its elevated mortality and disability rates.The efficacy of small-molecule neuroprotective agents has been impeded by challenges associated wit...Ischemic stroke(IS)represents a significant threat to brain health due to its elevated mortality and disability rates.The efficacy of small-molecule neuroprotective agents has been impeded by challenges associated with traversing the blood-brain barrier(BBB)and limited bioavailability.Conversely,advanced nano drug delivery systems hold promise for overcoming these obstacles by facilitating efficient transportation across the BBB and maintaining optimal drug concentrations.This review aims to explore advanced neuroprotective nano drug delivery systems as a means of effectively administering neuroprotective agents to the brain using pharmaceutical approaches in the treatment of IS.By examining these systems,researchers and clinicians can gain valuable insights and innovative concepts,illuminating the potential of advanced neuroprotective nano drug delivery systems.Leveraging these advancements can drive the progress of pioneering and efficacious therapeutic interventions for IS.展开更多
Residual stress is very important for the study of cardiovascular-relevant issues,such as assessing the vulnerability of atherosclerosis and aneurysm.In this paper,the circumferential residual stress of porcine aorta ...Residual stress is very important for the study of cardiovascular-relevant issues,such as assessing the vulnerability of atherosclerosis and aneurysm.In this paper,the circumferential residual stress of porcine aorta was characterized by combining ex vivo experiments with numerical studies.In the experiments,porcine aortic rings were prepared and cut open,and the cross sections of the opened aortic rings were extracted to construct finite element models.The 5-parameter Mooney-Rivlin model was chosen to describe the tensile mechanical behavior of the aorta.In numerical studies,based on the finite element models and hyperelastic material model,a pulling-back displacement was applied to reclose the models of the opened aortic rings,and the equivalent circumferential residual stress to the pre-opened aorta was analyzed.The results showed that the circumferential residual stress of the aorta generally decreased from the proximal to the distal ends,and the residual stresses of the aortic rings close to the distal end did not show a great difference.This work provides an improved understanding of the residual stress distribution in aorta and may be used as a more realistic initial condition for future stress analysis of the arterial tissue.展开更多
This study aimed to propose a novel biomimetic design strategy of an oral implant and to numerically examine its biomechanical effect according to clinical interests.The designed implant conceptually mimicked the morp...This study aimed to propose a novel biomimetic design strategy of an oral implant and to numerically examine its biomechanical effect according to clinical interests.The designed implant conceptually mimicked the morphology and elastic modulus of the mandibular bone.Basing on a CT-image-based patient-specific reconstruction of the tumor-excised mandible,the biomechanical effects of the implants with three materials(PEEK/n-HA/CF,PEEK/HA and Ti6Al4V),two surgical conditions(removed and retained muscles),and two postoperative stages(early and late)were fully investigated by a static finite element analysis.Moreover,according to clinical interests(e.g.failure and stability of the implant and rivets),maximum von Mises stresses and strains of the implant and rivets,maximum implant-bone gap in the early postoperative stage,and maximum von Mises stress of the mandible were mainly analyzed.The results showed that the implant composed of Ti6Al4V material was suitable for the current design strategy with respect to the other two PEEK-based materials.Although the implants in the muscle-retained surgical condition had relative greater indices compared to the muscle-removed surgical condition,the index difference between the two conditions was slight.The biomechanical indices indicating the failure and loosening risks of implant and rivets were much reduced in the late postoperative stage with respect to the early postoperative stage due to the osteointegration at the implant-bone interface.Generally,the proposed novel design strategy could be useful to guide the design of the oral implant addressing different implant materials and surgical conditions,and further made proper suggestion to clinicians and patients.展开更多
This article designs a novel type of non-bravais lattice photonic crystal fiber.To form the nesting complexperiod with positive and negative refractive index materials respectively,a cylinder with the same radius and ...This article designs a novel type of non-bravais lattice photonic crystal fiber.To form the nesting complexperiod with positive and negative refractive index materials respectively,a cylinder with the same radius and negative refractive index is introduced into the center of each lattice unit cell in the traditional square lattice air-holes photonic crystal fiber.The photonic band-gap of the photonic crystal fiber is calculated numerically by the plane wave expansion method.The result shows that compared with the traditional square photonic band-gap fiber(PBGF),when R=Λis 0.35,the refractive index of the substrate,airhole,and medium-column are 1.30,1.0,and–1:0,respectively.This new PBGF can transmit signal by the photonic band-gap effect.When the lattice constantΛvaries from 1:5μm to 3:0μm,the range of the wavelength ranges from 880 nm to 2300 nm.展开更多
基金financial support provided by the National Natural Science Foundation of Shanghai(No.20ZR1420000)Shanghai Shen Kang Center Research Physician Training Program on Innovation and Translation Capabilities(No.SHDC2022CRS051)Three-Year Action Plan for Improving Clinical Research Capacity of International Peace Maternal and Child Health Hospital,Shanghai Jiao Tong University School of Medicine(No.IPMCH2022CR1-05).
文摘Ischemic stroke(IS)represents a significant threat to brain health due to its elevated mortality and disability rates.The efficacy of small-molecule neuroprotective agents has been impeded by challenges associated with traversing the blood-brain barrier(BBB)and limited bioavailability.Conversely,advanced nano drug delivery systems hold promise for overcoming these obstacles by facilitating efficient transportation across the BBB and maintaining optimal drug concentrations.This review aims to explore advanced neuroprotective nano drug delivery systems as a means of effectively administering neuroprotective agents to the brain using pharmaceutical approaches in the treatment of IS.By examining these systems,researchers and clinicians can gain valuable insights and innovative concepts,illuminating the potential of advanced neuroprotective nano drug delivery systems.Leveraging these advancements can drive the progress of pioneering and efficacious therapeutic interventions for IS.
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.11772093,11972118,61821002)Australian Research Council(ARC)(Grant No.DP200103492).
文摘Residual stress is very important for the study of cardiovascular-relevant issues,such as assessing the vulnerability of atherosclerosis and aneurysm.In this paper,the circumferential residual stress of porcine aorta was characterized by combining ex vivo experiments with numerical studies.In the experiments,porcine aortic rings were prepared and cut open,and the cross sections of the opened aortic rings were extracted to construct finite element models.The 5-parameter Mooney-Rivlin model was chosen to describe the tensile mechanical behavior of the aorta.In numerical studies,based on the finite element models and hyperelastic material model,a pulling-back displacement was applied to reclose the models of the opened aortic rings,and the equivalent circumferential residual stress to the pre-opened aorta was analyzed.The results showed that the circumferential residual stress of the aorta generally decreased from the proximal to the distal ends,and the residual stresses of the aortic rings close to the distal end did not show a great difference.This work provides an improved understanding of the residual stress distribution in aorta and may be used as a more realistic initial condition for future stress analysis of the arterial tissue.
基金This work is partially supported by the National Nature Science Foundation of China(32171307,11972118,11772093)ARC(DP200103492,DP200101970).
文摘This study aimed to propose a novel biomimetic design strategy of an oral implant and to numerically examine its biomechanical effect according to clinical interests.The designed implant conceptually mimicked the morphology and elastic modulus of the mandibular bone.Basing on a CT-image-based patient-specific reconstruction of the tumor-excised mandible,the biomechanical effects of the implants with three materials(PEEK/n-HA/CF,PEEK/HA and Ti6Al4V),two surgical conditions(removed and retained muscles),and two postoperative stages(early and late)were fully investigated by a static finite element analysis.Moreover,according to clinical interests(e.g.failure and stability of the implant and rivets),maximum von Mises stresses and strains of the implant and rivets,maximum implant-bone gap in the early postoperative stage,and maximum von Mises stress of the mandible were mainly analyzed.The results showed that the implant composed of Ti6Al4V material was suitable for the current design strategy with respect to the other two PEEK-based materials.Although the implants in the muscle-retained surgical condition had relative greater indices compared to the muscle-removed surgical condition,the index difference between the two conditions was slight.The biomechanical indices indicating the failure and loosening risks of implant and rivets were much reduced in the late postoperative stage with respect to the early postoperative stage due to the osteointegration at the implant-bone interface.Generally,the proposed novel design strategy could be useful to guide the design of the oral implant addressing different implant materials and surgical conditions,and further made proper suggestion to clinicians and patients.
文摘This article designs a novel type of non-bravais lattice photonic crystal fiber.To form the nesting complexperiod with positive and negative refractive index materials respectively,a cylinder with the same radius and negative refractive index is introduced into the center of each lattice unit cell in the traditional square lattice air-holes photonic crystal fiber.The photonic band-gap of the photonic crystal fiber is calculated numerically by the plane wave expansion method.The result shows that compared with the traditional square photonic band-gap fiber(PBGF),when R=Λis 0.35,the refractive index of the substrate,airhole,and medium-column are 1.30,1.0,and–1:0,respectively.This new PBGF can transmit signal by the photonic band-gap effect.When the lattice constantΛvaries from 1:5μm to 3:0μm,the range of the wavelength ranges from 880 nm to 2300 nm.
