Flexible piezoresistive sensors based on biomimetic microstructures are prospective for broad application in motion monitoring.However,the design and preparation processes of most biomimetic microstructures in the exi...Flexible piezoresistive sensors based on biomimetic microstructures are prospective for broad application in motion monitoring.However,the design and preparation processes of most biomimetic microstructures in the existing studies are complicated,and there are few studies on pore size control.Herein,the porous structure of human bones was used as a biomimetic prototype,and optimally designed by creating a theoretical equivalent sensor model and a finite element model.Soluble raw materials such as sugar and salt in different particle sizes were pressed into porous templates.Based on the template method,porous structures in different pore sizes were prepared using polydimethylsiloxane(PDMS)polymer as the substrate.On this basis,graphene oxide conductive coating was prepared with the modified Hummers method and then deposited via dip coating onto the substrate.Finally,a PDMS-based porous structure biomimetic flexible piezoresistive sensor was developed.Mechanically,the deformation of the sensor under the same load increased with the pore size rising from 0.3 to 1.5 mm.Electrically,the resistance rang of the sensor was enlarged as the pore size rose.The resistance variation rates of samples with pore sizes of 0.3,1.0,and 1.5 mm at approximately the 200th cycle were 63%,79%,and 81%,respectively;at the 500th cycle,these values were 63%,77%,and 79%;and at the 1000th cycle,they stabilized at 63%,74%,and 76%.These results indicate that the fabricated sensor exhibits high stability and fatigue resistance.At the pressure of 0–25 kPa,the sensitivity rose from 0.0688 to 0.1260 kPa−1,and the performance was enhanced by 83%.After 1,000 cycles of compression testing,the signal output was stable,and no damage was caused to the substrate.Further application tests showed the biomimetic sensor accurately and effectively identified human joint motions and gestures,and has potential application value in human motion monitoring.展开更多
An instrument used for quantitative assessment of trabecular structure of radius on radiograph including trabecular number and trabecular width was developed using a microdensitometer and a single-chip microcomputer. ...An instrument used for quantitative assessment of trabecular structure of radius on radiograph including trabecular number and trabecular width was developed using a microdensitometer and a single-chip microcomputer. The device is characterized by its high sensitivity, good reproducibility, convenience and economy. The results obtained with the instrument were significantly correlated to actual bone mineral content, This device can be used for the diagnosis of osteoporosis, fluorosis, rickets and bone damages caused by cadmium.展开更多
The lightweight design of hydraulic quadruped robots,especially the lightweight design of the leg joint Hydraulic Drive Unit(HDU),can improve the robot's response speed,motion speed,endurance,and load capacity.How...The lightweight design of hydraulic quadruped robots,especially the lightweight design of the leg joint Hydraulic Drive Unit(HDU),can improve the robot's response speed,motion speed,endurance,and load capacity.However,the lightweight design of HDU is a huge challenge due to the need for structural strength.This paper is inspired by the geometric shape of fish bones and biomimetic reinforcing ribs on the surface of the HDU shell are designed to increase its strength and reduce its weight.First,a HDU shell with biomimetic fish bone reinforcing ribs structure is proposed.Then,the MATLAB toolbox and ANSYS finite element analysis module are used to optimize the parameters of the biomimetic reinforcing ribs structure and the overall layout of the shell.Finally,the HDU shell is manufactured using additive manufacturing technology,and a performance testing platform is built to conduct dynamic and static performance tests on the designed HDU.The experimental results show that the HDU with biomimetic fish bone reinforcing ribs has excellent dynamic performance and better static performance than the prototype model,and the weight of the shell is reduced by 20%compared to the prototype model.This work has broad application prospects in the lightweight and high-strength design of closed-pressure vessel components.展开更多
Trabecular bone holds the utmost importance due to its significance regarding early bone loss.Diseases like osteoporosis greatly affect the structure of the Trabecular bone which results in different outcomes like hig...Trabecular bone holds the utmost importance due to its significance regarding early bone loss.Diseases like osteoporosis greatly affect the structure of the Trabecular bone which results in different outcomes like high risk of fracture.The objective of this paper is to inspect the characteristics of the Trabecular Bone by using the Magnetic Resonance Imaging(MRI)technique.These characteristics prove to be quite helpful in studying different studies related to Trabecular bone such as osteoporosis.The things that were considered before the selection of the articles for the systematic review were language,research field,and electronic sources.Only those articles written in the English language were selected as it is the most prominent language used in scientific,engineering,computer science,and biomedical researches.This literature review was conducted on the articles published between 2006 and 2020.A total of 62 research papers out of 1050 papers were extracted which were according to our topic of review after screening abstract and article content for the title and abstract screening.The findings from those researches were compiled at the end of the result section.This systematic literature review presents a comprehensive report on scientific researches and studies that have been done in the medical area concerning trabecular bone.展开更多
Animal bone was employed as raw material to prepare hierarchical porous carbon by KOH activation. Rare metal selenium（Se） was encapsulated into hierarchical porous carbon successfully for the cathode material of Li...Animal bone was employed as raw material to prepare hierarchical porous carbon by KOH activation. Rare metal selenium（Se） was encapsulated into hierarchical porous carbon successfully for the cathode material of Li–Se battery, achieving the transformation of waste into energy,protecting environment and reducing the spread of the disease. Animal bone porous carbon（ABPC） acquires a specific surface area of 1244.7903 m^2·g^-1 and a pore volume of 0.594184 cm^3·g^-1. The composite Se/ABPC with 51 wt%Se was tested as a novel cathode for Li–Se batteries. The results show that Se/ABPC exhibits high specific capacity,good cycling stability and current-rate performance; at 0.1C,the composite Se/ABPC delivers a high reversible capacity of 705 mAh·g^-1 in the second cycle and 591 mAh·g^-1 after 98 cycles. Even at the current density of 2.0C, it can still maintain at a reversible capacity of 485 mAh·g^-1. The excellent electrochemical properties benefit from the high electron conductivity and the carbon with unique hierarchical porous structure. ABPC can be a promising carbon matrix for Li–Se batteries.展开更多
The goal of this study was to assess the effect of the intermittent combination of an antiresorptive agent （calcitonin） and an anabolic agent （vitamin D3） on treating the detrimental effects of Type 1 diabetes mel...The goal of this study was to assess the effect of the intermittent combination of an antiresorptive agent （calcitonin） and an anabolic agent （vitamin D3） on treating the detrimental effects of Type 1 diabetes mellitus （DM） on mandibular bone formation and growth. Forty 3-week-old male Wistar rats were divided into four groups： the control group （normal rats）, the control C＋D group （normal rats injected with calcitonin and vitamin D3）, the diabetic C＋D group （diabetic rats injected with calcitonin and vitamin D3） and the diabetic group （uncontrolled diabetic rats）. An experimental DM condition was induced in the male Wistar rats in the diabetic and diabetic C＋ D groups using a single dose of 60 mg.kg-1 body weight of streptozotocin. Calcitonin and vitamin D3 were simultaneously injected in the rats of the control C＋D and diabetic C＋D groups. All rats were killed after 4 weeks, and the right mandibles were evaluated by micro-computed tomography and histomorphometric analysis. Diabetic rats showed a significant deterioration in bone quality and bone formation （diabetic group）. By contrast, with the injection of calcitonin and vitamin D3, both bone parameters and bone formation significantly improved （diabetic C＋ D group） （P 〈 0.05）. These findings suggest that these two hormones might potentially improve various bone properties.展开更多
BACKGROUND Severe proximal humerus comminuted fractures are often accompanied by medial calcar comminuted fractures and loss of medial support,which are important factors that lead to internal fixation failure.The app...BACKGROUND Severe proximal humerus comminuted fractures are often accompanied by medial calcar comminuted fractures and loss of medial support,which are important factors that lead to internal fixation failure.The appropriate treatment for proximal humerus comminuted fractures has not been established.Therefore,this study assessed the outcomes of using a fibular autograft with locking plates to treat severe proximal humerus comminuted fractures.AIM To investigate the outcomes of using a fibular autograft with locking plates to treat severe proximal humerus comminuted fractures.METHODS This retrospective,comparative cohort study included two groups of patients.Group 1 comprised 22 patients and group 2 comprised 25 patients with complete follow-up data.Group 1 was treated with a fibular autograft with open reduction and locking plates to enable internal fixation.Group 2 was treated with open reduction and locking plates to enable internal fixation.The intraoperative blood loss volume from the shoulder wound,operative time,shoulder wound pain,bone fracture healing time,Constant-Murley score of the shoulder joint,preoperative Holden walking function score,Mallet score of the shoulder joint,and humeral neck-shaft angle during surgery of the two groups were compared,and the differences were analysed using an independent sample t-test.RESULTS Group 1 had a shorter mean operative time than group 2(2.25±0.30 h vs 2.76±0.44 h;P=0.000).Group 1 had a lower shoulder wound pain score on the first day after surgery than group 2(7.91±1.15 points vs 8.56±1.00 points;P=0.044).Group 1 had a shorter fracture healing time than group 2(2.68±0.48 mo vs 3.64±0.64 mo;P=0.000).Group 1 had higher Constant-Murley scores of the shoulder joint at 3,6,and 12 mo after surgery than group 2(76.64±4.02 points vs 72.72±3.02 points,86.36±3.53 points vs 82.96±3.40 points,and 87.95±2.77 points vs 84.68±2.63 points,respectively;P=0.000,0.002,and 0.000,respectively).Group 1 had higher Mallet scores of the shoulder joint at 3,6,and 12 mo after surgery than group 2(10.32±0.57 points vs 9.96±0.54 points,13.36±1.00 points vs 12.60±0.87 points,and 13.91±0.75 points vs 13.36±0.70 points,respectively;P=0.032,0.007,and 0.013,respectively).CONCLUSION Using locking plates with a fibular autograft can recreate medial support,facilitate fracture healing,and improve shoulder function;therefore,this may be an effective treatment option for severe proximal humerus comminuted fractures.展开更多
基金supported by the National Natural Science Foundation of China(52175270)the Project of Scientifc and Technological Development Plan of Jilin Province(20220508130RC)+3 种基金the Science and Technology Development Program of Jilin Province(YDZJ202501ZYTS370)the Scientific Research Project of Education Department of Jilin Province(JJKH20251196KJ)the Scientific Research Project of Education Department of Jilin Province(JJKH20251195KJ)the Key Project of State Key Laboratory of Changchun City(23GZZ14).
文摘Flexible piezoresistive sensors based on biomimetic microstructures are prospective for broad application in motion monitoring.However,the design and preparation processes of most biomimetic microstructures in the existing studies are complicated,and there are few studies on pore size control.Herein,the porous structure of human bones was used as a biomimetic prototype,and optimally designed by creating a theoretical equivalent sensor model and a finite element model.Soluble raw materials such as sugar and salt in different particle sizes were pressed into porous templates.Based on the template method,porous structures in different pore sizes were prepared using polydimethylsiloxane(PDMS)polymer as the substrate.On this basis,graphene oxide conductive coating was prepared with the modified Hummers method and then deposited via dip coating onto the substrate.Finally,a PDMS-based porous structure biomimetic flexible piezoresistive sensor was developed.Mechanically,the deformation of the sensor under the same load increased with the pore size rising from 0.3 to 1.5 mm.Electrically,the resistance rang of the sensor was enlarged as the pore size rose.The resistance variation rates of samples with pore sizes of 0.3,1.0,and 1.5 mm at approximately the 200th cycle were 63%,79%,and 81%,respectively;at the 500th cycle,these values were 63%,77%,and 79%;and at the 1000th cycle,they stabilized at 63%,74%,and 76%.These results indicate that the fabricated sensor exhibits high stability and fatigue resistance.At the pressure of 0–25 kPa,the sensitivity rose from 0.0688 to 0.1260 kPa−1,and the performance was enhanced by 83%.After 1,000 cycles of compression testing,the signal output was stable,and no damage was caused to the substrate.Further application tests showed the biomimetic sensor accurately and effectively identified human joint motions and gestures,and has potential application value in human motion monitoring.
文摘An instrument used for quantitative assessment of trabecular structure of radius on radiograph including trabecular number and trabecular width was developed using a microdensitometer and a single-chip microcomputer. The device is characterized by its high sensitivity, good reproducibility, convenience and economy. The results obtained with the instrument were significantly correlated to actual bone mineral content, This device can be used for the diagnosis of osteoporosis, fluorosis, rickets and bone damages caused by cadmium.
文摘The lightweight design of hydraulic quadruped robots,especially the lightweight design of the leg joint Hydraulic Drive Unit(HDU),can improve the robot's response speed,motion speed,endurance,and load capacity.However,the lightweight design of HDU is a huge challenge due to the need for structural strength.This paper is inspired by the geometric shape of fish bones and biomimetic reinforcing ribs on the surface of the HDU shell are designed to increase its strength and reduce its weight.First,a HDU shell with biomimetic fish bone reinforcing ribs structure is proposed.Then,the MATLAB toolbox and ANSYS finite element analysis module are used to optimize the parameters of the biomimetic reinforcing ribs structure and the overall layout of the shell.Finally,the HDU shell is manufactured using additive manufacturing technology,and a performance testing platform is built to conduct dynamic and static performance tests on the designed HDU.The experimental results show that the HDU with biomimetic fish bone reinforcing ribs has excellent dynamic performance and better static performance than the prototype model,and the weight of the shell is reduced by 20%compared to the prototype model.This work has broad application prospects in the lightweight and high-strength design of closed-pressure vessel components.
文摘Trabecular bone holds the utmost importance due to its significance regarding early bone loss.Diseases like osteoporosis greatly affect the structure of the Trabecular bone which results in different outcomes like high risk of fracture.The objective of this paper is to inspect the characteristics of the Trabecular Bone by using the Magnetic Resonance Imaging(MRI)technique.These characteristics prove to be quite helpful in studying different studies related to Trabecular bone such as osteoporosis.The things that were considered before the selection of the articles for the systematic review were language,research field,and electronic sources.Only those articles written in the English language were selected as it is the most prominent language used in scientific,engineering,computer science,and biomedical researches.This literature review was conducted on the articles published between 2006 and 2020.A total of 62 research papers out of 1050 papers were extracted which were according to our topic of review after screening abstract and article content for the title and abstract screening.The findings from those researches were compiled at the end of the result section.This systematic literature review presents a comprehensive report on scientific researches and studies that have been done in the medical area concerning trabecular bone.
基金financially supported by the National Natural Science Foundation of China(Nos.51272156,21373137 and 21333007)the City Committee of Science and Technology Project of Shanghai(No.14JC1491800)the New Century Excellent Talents in University(Nos.NCET-13-0371)
文摘Animal bone was employed as raw material to prepare hierarchical porous carbon by KOH activation. Rare metal selenium（Se） was encapsulated into hierarchical porous carbon successfully for the cathode material of Li–Se battery, achieving the transformation of waste into energy,protecting environment and reducing the spread of the disease. Animal bone porous carbon（ABPC） acquires a specific surface area of 1244.7903 m^2·g^-1 and a pore volume of 0.594184 cm^3·g^-1. The composite Se/ABPC with 51 wt%Se was tested as a novel cathode for Li–Se batteries. The results show that Se/ABPC exhibits high specific capacity,good cycling stability and current-rate performance; at 0.1C,the composite Se/ABPC delivers a high reversible capacity of 705 mAh·g^-1 in the second cycle and 591 mAh·g^-1 after 98 cycles. Even at the current density of 2.0C, it can still maintain at a reversible capacity of 485 mAh·g^-1. The excellent electrochemical properties benefit from the high electron conductivity and the carbon with unique hierarchical porous structure. ABPC can be a promising carbon matrix for Li–Se batteries.
基金the National Plan for Science,Technology and Innovation(MAARIFAH)-King Abdulaziz City for Science Technology-the Kingdom of Saudi Arabia award number(12-MED2735-03)Science and Technology Unit,King Abdulaziz University for technical support
文摘The goal of this study was to assess the effect of the intermittent combination of an antiresorptive agent （calcitonin） and an anabolic agent （vitamin D3） on treating the detrimental effects of Type 1 diabetes mellitus （DM） on mandibular bone formation and growth. Forty 3-week-old male Wistar rats were divided into four groups： the control group （normal rats）, the control C＋D group （normal rats injected with calcitonin and vitamin D3）, the diabetic C＋D group （diabetic rats injected with calcitonin and vitamin D3） and the diabetic group （uncontrolled diabetic rats）. An experimental DM condition was induced in the male Wistar rats in the diabetic and diabetic C＋ D groups using a single dose of 60 mg.kg-1 body weight of streptozotocin. Calcitonin and vitamin D3 were simultaneously injected in the rats of the control C＋D and diabetic C＋D groups. All rats were killed after 4 weeks, and the right mandibles were evaluated by micro-computed tomography and histomorphometric analysis. Diabetic rats showed a significant deterioration in bone quality and bone formation （diabetic group）. By contrast, with the injection of calcitonin and vitamin D3, both bone parameters and bone formation significantly improved （diabetic C＋ D group） （P 〈 0.05）. These findings suggest that these two hormones might potentially improve various bone properties.
文摘BACKGROUND Severe proximal humerus comminuted fractures are often accompanied by medial calcar comminuted fractures and loss of medial support,which are important factors that lead to internal fixation failure.The appropriate treatment for proximal humerus comminuted fractures has not been established.Therefore,this study assessed the outcomes of using a fibular autograft with locking plates to treat severe proximal humerus comminuted fractures.AIM To investigate the outcomes of using a fibular autograft with locking plates to treat severe proximal humerus comminuted fractures.METHODS This retrospective,comparative cohort study included two groups of patients.Group 1 comprised 22 patients and group 2 comprised 25 patients with complete follow-up data.Group 1 was treated with a fibular autograft with open reduction and locking plates to enable internal fixation.Group 2 was treated with open reduction and locking plates to enable internal fixation.The intraoperative blood loss volume from the shoulder wound,operative time,shoulder wound pain,bone fracture healing time,Constant-Murley score of the shoulder joint,preoperative Holden walking function score,Mallet score of the shoulder joint,and humeral neck-shaft angle during surgery of the two groups were compared,and the differences were analysed using an independent sample t-test.RESULTS Group 1 had a shorter mean operative time than group 2(2.25±0.30 h vs 2.76±0.44 h;P=0.000).Group 1 had a lower shoulder wound pain score on the first day after surgery than group 2(7.91±1.15 points vs 8.56±1.00 points;P=0.044).Group 1 had a shorter fracture healing time than group 2(2.68±0.48 mo vs 3.64±0.64 mo;P=0.000).Group 1 had higher Constant-Murley scores of the shoulder joint at 3,6,and 12 mo after surgery than group 2(76.64±4.02 points vs 72.72±3.02 points,86.36±3.53 points vs 82.96±3.40 points,and 87.95±2.77 points vs 84.68±2.63 points,respectively;P=0.000,0.002,and 0.000,respectively).Group 1 had higher Mallet scores of the shoulder joint at 3,6,and 12 mo after surgery than group 2(10.32±0.57 points vs 9.96±0.54 points,13.36±1.00 points vs 12.60±0.87 points,and 13.91±0.75 points vs 13.36±0.70 points,respectively;P=0.032,0.007,and 0.013,respectively).CONCLUSION Using locking plates with a fibular autograft can recreate medial support,facilitate fracture healing,and improve shoulder function;therefore,this may be an effective treatment option for severe proximal humerus comminuted fractures.
