Vibration isolation is vital in engineering machinery,as it not only seriously affects the service life of machine components but also reduces the operating efficiency.Recently,metamaterials have been proposed for cus...Vibration isolation is vital in engineering machinery,as it not only seriously affects the service life of machine components but also reduces the operating efficiency.Recently,metamaterials have been proposed for customized vibration-isolation needs through various functional designs.As a synthetic material,polymer materials have the advantages of good elasticity,low density,high specific strength,good corrosion resistance and easy processing,making it an ideal raw material for vibration-isolation metamaterials.At the same time,the rapid development of additive manufacturing(AM)provides a feasible method for preparing polymeric vibration-isolation metamaterials with complex structures.In this paper,we systematically analyze the vibration-isolation mechanism of metamaterials,review the applications of metamaterials in vibration isolation and the research on polymer metamaterials,and survey the AM process methods for polymer metamaterials.Finally,the prospects and directions for the development of polymer vibration-isolation metamaterials are envisioned,providing new ideas for further research on polymer metamaterials in the field of vibration isolation.展开更多
Introduction:Internal heat-type acupuncture therapy is a new therapeutic method that integrates acupuncture and heat therapy and effectively reduces local muscle inflammation.It has a good effect on the clinical appli...Introduction:Internal heat-type acupuncture therapy is a new therapeutic method that integrates acupuncture and heat therapy and effectively reduces local muscle inflammation.It has a good effect on the clinical application of osteoporosis.The purpose of this study was to assess the improvement of glucocorticoid-induced osteoporosis(GIOP)after internal heat-type acupuncture treatment as well as its role in promoting the balance of bone remodeling in the GIOP rabbit model by regulating the triplet of osteoprotegerin(OPG)-receptor activator of nuclear factor-KB ligand(RANKL)-receptor activator of nuclear factor-KB(RANK).Methods:The rabbits were divided into the control,model(GIOP),GIOP+Alendronate,and GIOP+Internal heat-type acupuncture groups,with 8 rabbits in each group.At the end of the treatment,all rabbits were sacrificed.The pathologic changes of lumbar vertebrae were observed by x-ray,the morphology of lumbar trabecular bone was observed by HE staining,and the apoptosis of lumbar vertebrae was detected by Tunel.The protein expressions of OPG,RANKL,and RANK in lumbar vertebrae were detected by immunohistochemistry staining,immunofluorescence staining,and Western blotting.Results:Internal heat-type acupuncture partly prevented osteopenia among GIOP-induced rabbits,improved the morphology of lumbar vertebrae,and inhibited the apoptosis of lumbar vertebrae osteocytes.Moreover,by increasing the protein expression level of OPG and reducing the protein expression of RANKL and RANK,internal heat-type acupuncture effectively promoted the balance of bone remodeling and eventually achieved the treatment of GIOP.Conclusion:Internal heat-type acupuncture therapy may promote the balance of bone remodeling by regulating the triplet of osteoprotegerin-receptor activator of nuclear factor-KB ligand-receptor activator of nuclear factor-KB,thereby treating osteoporosis which was induced by glucocorticoid.展开更多
基金supported by National Natural Science Foundation of China(Nos.52475398,52235008,and U2341270).
文摘Vibration isolation is vital in engineering machinery,as it not only seriously affects the service life of machine components but also reduces the operating efficiency.Recently,metamaterials have been proposed for customized vibration-isolation needs through various functional designs.As a synthetic material,polymer materials have the advantages of good elasticity,low density,high specific strength,good corrosion resistance and easy processing,making it an ideal raw material for vibration-isolation metamaterials.At the same time,the rapid development of additive manufacturing(AM)provides a feasible method for preparing polymeric vibration-isolation metamaterials with complex structures.In this paper,we systematically analyze the vibration-isolation mechanism of metamaterials,review the applications of metamaterials in vibration isolation and the research on polymer metamaterials,and survey the AM process methods for polymer metamaterials.Finally,the prospects and directions for the development of polymer vibration-isolation metamaterials are envisioned,providing new ideas for further research on polymer metamaterials in the field of vibration isolation.
基金supported by the National Natural Science Foundation of China(Nos.81860893 and 82360987)Ningxia Hui Autonomous Region key research and development project(Nos.2022BEG03134).
文摘Introduction:Internal heat-type acupuncture therapy is a new therapeutic method that integrates acupuncture and heat therapy and effectively reduces local muscle inflammation.It has a good effect on the clinical application of osteoporosis.The purpose of this study was to assess the improvement of glucocorticoid-induced osteoporosis(GIOP)after internal heat-type acupuncture treatment as well as its role in promoting the balance of bone remodeling in the GIOP rabbit model by regulating the triplet of osteoprotegerin(OPG)-receptor activator of nuclear factor-KB ligand(RANKL)-receptor activator of nuclear factor-KB(RANK).Methods:The rabbits were divided into the control,model(GIOP),GIOP+Alendronate,and GIOP+Internal heat-type acupuncture groups,with 8 rabbits in each group.At the end of the treatment,all rabbits were sacrificed.The pathologic changes of lumbar vertebrae were observed by x-ray,the morphology of lumbar trabecular bone was observed by HE staining,and the apoptosis of lumbar vertebrae was detected by Tunel.The protein expressions of OPG,RANKL,and RANK in lumbar vertebrae were detected by immunohistochemistry staining,immunofluorescence staining,and Western blotting.Results:Internal heat-type acupuncture partly prevented osteopenia among GIOP-induced rabbits,improved the morphology of lumbar vertebrae,and inhibited the apoptosis of lumbar vertebrae osteocytes.Moreover,by increasing the protein expression level of OPG and reducing the protein expression of RANKL and RANK,internal heat-type acupuncture effectively promoted the balance of bone remodeling and eventually achieved the treatment of GIOP.Conclusion:Internal heat-type acupuncture therapy may promote the balance of bone remodeling by regulating the triplet of osteoprotegerin-receptor activator of nuclear factor-KB ligand-receptor activator of nuclear factor-KB,thereby treating osteoporosis which was induced by glucocorticoid.
