The solidification microstructure has an important effect on the mechanical properties of castings. Therefore, an FE （Finite Element） - CA （Cellular Automaton） coupling model was developed for the simulation of so...The solidification microstructure has an important effect on the mechanical properties of castings. Therefore, an FE （Finite Element） - CA （Cellular Automaton） coupling model was developed for the simulation of solidification structure during the continuous casting process of 72A tire cord steel. In the model, the effect of phase transformation （λ→γ→α） during solidification was considered based on a thermodynamic database. The effect of electromagnetic stirring （EMS） was determined by increasing both the thermal conductivity and crystal formation rate in the liquid phase. The results show that the cooling curves and solidification structure calculated by this model agree well with the experimental results. The optimum pouring temperature range for tire cord steel casting was also discussed based on the present model. By comprehensive consideration of billet quality and smooth production, the pouring temperature should be controlled at about 1,495 ℃ under the casting conditions of the local plant in this study.展开更多
Because of the complex nerve anatomy and limited regeneration ability of natural tissue,the current treatment effect for long-distance peripheral nerve regeneration and spinal cord injury(SCI)repair is not satisfactor...Because of the complex nerve anatomy and limited regeneration ability of natural tissue,the current treatment effect for long-distance peripheral nerve regeneration and spinal cord injury(SCI)repair is not satisfactory.As an alternative method,tissue engineering is a promising method to regenerate peripheral nerve and spinal cord,and can provide structures and functions similar to natural tissues through scaffold materials and seed cells.Recently,the rapid development of 3D printing technology enables researchers to create novel 3D constructs with sophisticated structures and diverse functions to achieve high bionics of structures and functions.In this review,we first outlined the anatomy of peripheral nerve and spinal cord,as well as the current treatment strategies for the peripheral nerve injury and SCI in clinical.After that,the design considerations of peripheral nerve and spinal cord tissue engineering were discussed,and various 3D printing technologies applicable to neural tissue engineering were elaborated,including inkjet,extrusion-based,stereolithography,projection-based,and emerging printing technologies.Finally,we focused on the application of 3D printing technology in peripheral nerve regeneration and spinal cord repair,as well as the challenges and prospects in this research field.展开更多
Gastrodin, an active component of tall gastrodia tuber, is widely used in the treatment of dizziness, paralysis, epilepsy, stroke and dementia, and exhibits a neuroprotective effect. A rat model of spinal cord injury ...Gastrodin, an active component of tall gastrodia tuber, is widely used in the treatment of dizziness, paralysis, epilepsy, stroke and dementia, and exhibits a neuroprotective effect. A rat model of spinal cord injury was established using Allen＇s method, and gastrodin was administered via the subarachnoid cavity and by intraperitoneal injection for 7 days. Results show that gastrodin promoted the secretion of brain-derived neurotrophic factor in rats with spinal cord injury. After gastrodin treatment, the maximum angle of the inclined plane test, and the Basso, Beattie and Bresnahan scores increased. Moreover, gastrodin improved neural tissue recovery in the injured spinal cord. These results demonstrate that gastrodin promotes the secretion of brain-derived neurotrophic factor, contributes to the recovery of neurological function, and protects neural cells against injury.展开更多
基金supported by the National Basic Research Program of China (grant No.2010CB630806)
文摘The solidification microstructure has an important effect on the mechanical properties of castings. Therefore, an FE （Finite Element） - CA （Cellular Automaton） coupling model was developed for the simulation of solidification structure during the continuous casting process of 72A tire cord steel. In the model, the effect of phase transformation （λ→γ→α） during solidification was considered based on a thermodynamic database. The effect of electromagnetic stirring （EMS） was determined by increasing both the thermal conductivity and crystal formation rate in the liquid phase. The results show that the cooling curves and solidification structure calculated by this model agree well with the experimental results. The optimum pouring temperature range for tire cord steel casting was also discussed based on the present model. By comprehensive consideration of billet quality and smooth production, the pouring temperature should be controlled at about 1,495 ℃ under the casting conditions of the local plant in this study.
基金financially sponsored by the National Key Research and Development Program of China(2018YFA0703000)the National Natural Science Foundation of China(No.U1909218)+2 种基金the Joint Funds of Guangdong Basic and Applied Basic Research Foundation(2019A1515110261)the Special Projects in Key Fields from the Department of Education of Guangdong Province(2022ZDZX2059)the Dongguan Science and Technology of Social Development Program(20221800905072)。
文摘Because of the complex nerve anatomy and limited regeneration ability of natural tissue,the current treatment effect for long-distance peripheral nerve regeneration and spinal cord injury(SCI)repair is not satisfactory.As an alternative method,tissue engineering is a promising method to regenerate peripheral nerve and spinal cord,and can provide structures and functions similar to natural tissues through scaffold materials and seed cells.Recently,the rapid development of 3D printing technology enables researchers to create novel 3D constructs with sophisticated structures and diverse functions to achieve high bionics of structures and functions.In this review,we first outlined the anatomy of peripheral nerve and spinal cord,as well as the current treatment strategies for the peripheral nerve injury and SCI in clinical.After that,the design considerations of peripheral nerve and spinal cord tissue engineering were discussed,and various 3D printing technologies applicable to neural tissue engineering were elaborated,including inkjet,extrusion-based,stereolithography,projection-based,and emerging printing technologies.Finally,we focused on the application of 3D printing technology in peripheral nerve regeneration and spinal cord repair,as well as the challenges and prospects in this research field.
基金financially supported by the National Natural Science Foundation of China, No. 81171799
文摘Gastrodin, an active component of tall gastrodia tuber, is widely used in the treatment of dizziness, paralysis, epilepsy, stroke and dementia, and exhibits a neuroprotective effect. A rat model of spinal cord injury was established using Allen＇s method, and gastrodin was administered via the subarachnoid cavity and by intraperitoneal injection for 7 days. Results show that gastrodin promoted the secretion of brain-derived neurotrophic factor in rats with spinal cord injury. After gastrodin treatment, the maximum angle of the inclined plane test, and the Basso, Beattie and Bresnahan scores increased. Moreover, gastrodin improved neural tissue recovery in the injured spinal cord. These results demonstrate that gastrodin promotes the secretion of brain-derived neurotrophic factor, contributes to the recovery of neurological function, and protects neural cells against injury.
