A flux linkage compensation field oriented control (FOC) method was proposed to suppress the speed and torque ripples of a brushless wound-field synchronous motor in its starting process. The starting process was anal...A flux linkage compensation field oriented control (FOC) method was proposed to suppress the speed and torque ripples of a brushless wound-field synchronous motor in its starting process. The starting process was analyzed and the model of wound-field synchronous electric machine was established. The change of field current of the electric machine was described mathematically for simplified exciter and rotate rectifier. Based on the traditional field control, the flux linkage compensation was introduced in d-axis current to counteract the flux ripple. Some simulation and preliminary experiments were implemented. The results show that the proposed method is feasible and effective.展开更多
Objective Diabetic patients pose a greater challenge in managing chronic wound healing,leading to a higher amputation risk compared to non-diabetic patients.Due to their paracrine function by secreting various cytokin...Objective Diabetic patients pose a greater challenge in managing chronic wound healing,leading to a higher amputation risk compared to non-diabetic patients.Due to their paracrine function by secreting various cytokines and angiogenic factors,mesenchymal stem cells(MSCs)have been acknowledged to be a potential agent in modulating wound healing process.However,post-transplanted MSCs are vulnerable to death,indicating poor survival and migration ability in the wound site of the host,especially under hyperglycemia.As hyperglycemia induces reactive oxygen species(ROS)generation and cellular apoptosis,improvement of MSCs survival and migration potentials under hyperglycemia could contribute to a more efficient MSCs-based wound healing therapy.Salidroside(Sa),a small-molecule drug derived from Rhodiola plant,has been proved to enhance the paracrine function of skeletal muscle cells,as well as their migration even under hypoxichyperglycemia.Herein,we investigated whether Sa could improve the survival and migration potentials of MSCs,subsequently enhance the wound healing process under hyperglycemia.Methods MSCs were cultured under three conditions:low glucose,high glucose,and high glucose+Sa.qPCR analysis and western blotting were done to examine the mRNA and protein expression level of several factors which are important in upregulating the wound healing process.MTT colorimetric assay,intracellular ROS detection,and flow cytometry assay were employed to examine the effect of Sa in MSCs survival.Transwell chamber assay,scratch assay,and phalloidin staining were done to elucidate the role of Sa in regulating MSCs migration potential.For in vivo experiment,diabetic wound healing mice model was generated to elucidate the effect of Sa-pretreated MSCs transplantation in wound closure rate,as well as re-epithelization status,observed with hematoxylin and eosin staining.The diabetic wound healing mice model were divided into three groups:1)mice injected with PBS,2)mice transplanted with PBS-pretreated MSCs,and 3)mice transplanted with Sa-pretreated MSCs.Results(1)Hyperglycemic condition induced the generation of ROS and suppressed total cell number of MSCs,while Sa treatment into MSCs restored these hyperglycemia-induced alterations.In line with this,total apoptotic cells were also suppressed by treating MSCs with Sa.The expression level of cell survival factor,heme-oxygenase 1(HO-1),was enhanced in Sa-pretreated MSCs.Further treatment of HO-1 inhibitor into Sa-pretreated MSCs nullified the ROS level and total apoptotic cells,indica-ting the importance of HO-1 in mediating the Sa-induced survival of MSCs under hyperglycemia.(2)Transwell chamber and scratch assay results showed that Sa-pretreated MSCs have a higher migration potential under hyperglycemia,supported by higher F-actin polymerization fractal dimension.Fibroblast growth factor 2(FGF2)and hepatocyte growth factor(HGF)expression level,which are essential factors for cell migration,were also improved in Sa-pretreated MSCs under hyperglycemia.(3)In diabetic wound healing mice model,transplantation of Sa-pretreated MSCs resulted in significantly improved wound closure rate and re-epithelization.The protein levels of HO-1,FGF2,and HGF were also enhanced in the tissues obtained from the wound site of diabetic wound healing mice model which were transplanted with Sa-pretreated MSCs.Conclusions Salidroside pretreatment on MSCs could improve their survival and migration potentials,subsequently promoting wound healing process under hyperglycemia.This prospective MSC-based therapy could serve as a novel strategy to improve diabetic wound healing.展开更多
This paper calculated load-carrying of isogrid and orthogrid of carbon-epoxy composite trellis wound structure(C/E CTWS) using non-linear finite element method.Based on the analysis,test cases were designed and tests ...This paper calculated load-carrying of isogrid and orthogrid of carbon-epoxy composite trellis wound structure(C/E CTWS) using non-linear finite element method.Based on the analysis,test cases were designed and tests of axial compression were carried.Analysis result and test result fit well.In order to be used in the project,this kind of structure cut-out repairing was calculated.The method presented in this paper has been proved and can be used to solve complicated engineering problems.According to calculations and experimental results combined with application,a principle of choosing wound structure is obtained and principle could be applied to engineering.展开更多
Objective To research the relation between the time-dependent appearances of myofibroblasts during the repair of contused skeletal muscle in rat and wound age determination. Methods A total of 35 SD male rats were div...Objective To research the relation between the time-dependent appearances of myofibroblasts during the repair of contused skeletal muscle in rat and wound age determination. Methods A total of 35 SD male rats were divided into the control and six injured groups according to wound age as follows: 12 h, 1 d, 5 d, 7 d, 10 d and 14 d after injury. The appearances of myofibroblasts were detected by HE staining, immunohistochemistry and confocal laser scanning microscopy. Masson's trichrome staining was utilized to examine collagen accumulation in the contused areas. Results Immunohistochemical staining showed that α-SMA+myofibroblasts were initially observed at 5 d post-injury. The average ratio of myofibroblasts was highest at 14 d post-injury, with all samples, ratios more than 50%. In the other five groups, the average of α-SMA positive ratios were less than 50%. The collagen stained areas in the contused zones, concomitant with myofibroblast appearance, were increasingly augmented along with advances of posttraumatic interval. Conclusion The immunohistochemical detection of myofibroblasts can be applied to wound age determination. The myofibroblasts might be involved in collagen deposition during the repair of contused skeletal muscle in rat.展开更多
目的:探究多学科诊疗模式(multidisciplinary team,MDT)在慢性难愈合创面诊疗中的应用成效,为优化此类疾病的临床诊疗提供新思路。方法:回顾性分析2015年1月至2023年10月在北京大学第三医院接受手术治疗的慢性难愈合创面患者的临床资料...目的:探究多学科诊疗模式(multidisciplinary team,MDT)在慢性难愈合创面诊疗中的应用成效,为优化此类疾病的临床诊疗提供新思路。方法:回顾性分析2015年1月至2023年10月在北京大学第三医院接受手术治疗的慢性难愈合创面患者的临床资料,共纳入患者456例,包括男性290例,女性166例,平均年龄(49.4±16.9)岁。根据是否进行术前MDT讨论,将患者分为MDT讨论组和非MDT讨论组。MDT总体执行流程包括:启动与医务处备案、收集资料与初次MDT讨论、告知患者诊疗方案并严格执行、病情变化需再次MDT讨论。比较两组患者的一般临床资料、麻醉风险分级、合并症(高血压、糖尿病、冠心病)、慢性难愈合创面的发生病因与部位等资料的差异。治疗效果的主要观察与结局指标包括入院后达到创面愈合所需的手术次数、创面愈合后的复发率、围手术期并发症(肺部感染、严重心血管事件、静脉血栓栓塞症、脑卒中及谵妄等)的发生率、患者满意度评分等。结果:MDT讨论组患者189例,非MDT讨论组患者267例,两组患者的年龄、性别、体重指数、美国麻醉医师协会(American Society of Anesthesiologists,ASA)分级、合并症、慢性难愈合创面的病因与部位等临床资料差异无统计学意义(P>0.05)。MDT讨论组与非MDT讨论组患者获得创面愈合所需的平均手术次数分别为(2.1±1.1)次与(2.8±1.6)次,差异有统计学意义(P<0.001),这种差异在糖尿病溃疡、外伤或手术后感染、放疗后不愈合等3个病因造成的慢性难愈合创面中也有统计学意义(P<0.05)。非MDT讨论组患者在创面痊愈后的复发率是18.0%,稍高于MDT讨论组的14.3%,但差异无统计学意义(P>0.05)。在围手术期并发症方面,非MDT讨论组的发生率也较MDT讨论组高(3.7%vs.2.6%),但差异无统计学意义(P>0.05)。患者满意度方面,MDT讨论组的评分显著高于非MDT讨论组,差异有统计学意义(96.5 vs.91.1,P=0.028)。结论:多学科诊疗模式能够显著减少慢性难愈合创面患者的住院手术次数,提升治愈效率,提高患者满意度,是优化慢性难愈合创面临床诊疗成效的推荐模式。展开更多
基金Sponsored by the NSFC General Project (51177135)the Key Project of Natural Science Foundation of Shaanxi Province (2011GZ013)
文摘A flux linkage compensation field oriented control (FOC) method was proposed to suppress the speed and torque ripples of a brushless wound-field synchronous motor in its starting process. The starting process was analyzed and the model of wound-field synchronous electric machine was established. The change of field current of the electric machine was described mathematically for simplified exciter and rotate rectifier. Based on the traditional field control, the flux linkage compensation was introduced in d-axis current to counteract the flux ripple. Some simulation and preliminary experiments were implemented. The results show that the proposed method is feasible and effective.
基金Supported by grants from the National Natural Science Foundation of China ( 81372202,81872273, 31871367)
文摘Objective Diabetic patients pose a greater challenge in managing chronic wound healing,leading to a higher amputation risk compared to non-diabetic patients.Due to their paracrine function by secreting various cytokines and angiogenic factors,mesenchymal stem cells(MSCs)have been acknowledged to be a potential agent in modulating wound healing process.However,post-transplanted MSCs are vulnerable to death,indicating poor survival and migration ability in the wound site of the host,especially under hyperglycemia.As hyperglycemia induces reactive oxygen species(ROS)generation and cellular apoptosis,improvement of MSCs survival and migration potentials under hyperglycemia could contribute to a more efficient MSCs-based wound healing therapy.Salidroside(Sa),a small-molecule drug derived from Rhodiola plant,has been proved to enhance the paracrine function of skeletal muscle cells,as well as their migration even under hypoxichyperglycemia.Herein,we investigated whether Sa could improve the survival and migration potentials of MSCs,subsequently enhance the wound healing process under hyperglycemia.Methods MSCs were cultured under three conditions:low glucose,high glucose,and high glucose+Sa.qPCR analysis and western blotting were done to examine the mRNA and protein expression level of several factors which are important in upregulating the wound healing process.MTT colorimetric assay,intracellular ROS detection,and flow cytometry assay were employed to examine the effect of Sa in MSCs survival.Transwell chamber assay,scratch assay,and phalloidin staining were done to elucidate the role of Sa in regulating MSCs migration potential.For in vivo experiment,diabetic wound healing mice model was generated to elucidate the effect of Sa-pretreated MSCs transplantation in wound closure rate,as well as re-epithelization status,observed with hematoxylin and eosin staining.The diabetic wound healing mice model were divided into three groups:1)mice injected with PBS,2)mice transplanted with PBS-pretreated MSCs,and 3)mice transplanted with Sa-pretreated MSCs.Results(1)Hyperglycemic condition induced the generation of ROS and suppressed total cell number of MSCs,while Sa treatment into MSCs restored these hyperglycemia-induced alterations.In line with this,total apoptotic cells were also suppressed by treating MSCs with Sa.The expression level of cell survival factor,heme-oxygenase 1(HO-1),was enhanced in Sa-pretreated MSCs.Further treatment of HO-1 inhibitor into Sa-pretreated MSCs nullified the ROS level and total apoptotic cells,indica-ting the importance of HO-1 in mediating the Sa-induced survival of MSCs under hyperglycemia.(2)Transwell chamber and scratch assay results showed that Sa-pretreated MSCs have a higher migration potential under hyperglycemia,supported by higher F-actin polymerization fractal dimension.Fibroblast growth factor 2(FGF2)and hepatocyte growth factor(HGF)expression level,which are essential factors for cell migration,were also improved in Sa-pretreated MSCs under hyperglycemia.(3)In diabetic wound healing mice model,transplantation of Sa-pretreated MSCs resulted in significantly improved wound closure rate and re-epithelization.The protein levels of HO-1,FGF2,and HGF were also enhanced in the tissues obtained from the wound site of diabetic wound healing mice model which were transplanted with Sa-pretreated MSCs.Conclusions Salidroside pretreatment on MSCs could improve their survival and migration potentials,subsequently promoting wound healing process under hyperglycemia.This prospective MSC-based therapy could serve as a novel strategy to improve diabetic wound healing.
文摘This paper calculated load-carrying of isogrid and orthogrid of carbon-epoxy composite trellis wound structure(C/E CTWS) using non-linear finite element method.Based on the analysis,test cases were designed and tests of axial compression were carried.Analysis result and test result fit well.In order to be used in the project,this kind of structure cut-out repairing was calculated.The method presented in this paper has been proved and can be used to solve complicated engineering problems.According to calculations and experimental results combined with application,a principle of choosing wound structure is obtained and principle could be applied to engineering.
基金This study was financially supported in part bythe research funds from the National Natural Science Foundation of China （81202383）, the Doctoral Program of Higher Education of China （20122104110025） and Program for Young Innovative Research Team in China University of Political Science and Law.
文摘Objective To research the relation between the time-dependent appearances of myofibroblasts during the repair of contused skeletal muscle in rat and wound age determination. Methods A total of 35 SD male rats were divided into the control and six injured groups according to wound age as follows: 12 h, 1 d, 5 d, 7 d, 10 d and 14 d after injury. The appearances of myofibroblasts were detected by HE staining, immunohistochemistry and confocal laser scanning microscopy. Masson's trichrome staining was utilized to examine collagen accumulation in the contused areas. Results Immunohistochemical staining showed that α-SMA+myofibroblasts were initially observed at 5 d post-injury. The average ratio of myofibroblasts was highest at 14 d post-injury, with all samples, ratios more than 50%. In the other five groups, the average of α-SMA positive ratios were less than 50%. The collagen stained areas in the contused zones, concomitant with myofibroblast appearance, were increasingly augmented along with advances of posttraumatic interval. Conclusion The immunohistochemical detection of myofibroblasts can be applied to wound age determination. The myofibroblasts might be involved in collagen deposition during the repair of contused skeletal muscle in rat.
基金This study was jointly supported by the Na- tional Science Foundation for Young Scientists of China （81001347） and the Innovation Foundation of Shanxi Medical University （01201409）.
文摘目的:探究多学科诊疗模式(multidisciplinary team,MDT)在慢性难愈合创面诊疗中的应用成效,为优化此类疾病的临床诊疗提供新思路。方法:回顾性分析2015年1月至2023年10月在北京大学第三医院接受手术治疗的慢性难愈合创面患者的临床资料,共纳入患者456例,包括男性290例,女性166例,平均年龄(49.4±16.9)岁。根据是否进行术前MDT讨论,将患者分为MDT讨论组和非MDT讨论组。MDT总体执行流程包括:启动与医务处备案、收集资料与初次MDT讨论、告知患者诊疗方案并严格执行、病情变化需再次MDT讨论。比较两组患者的一般临床资料、麻醉风险分级、合并症(高血压、糖尿病、冠心病)、慢性难愈合创面的发生病因与部位等资料的差异。治疗效果的主要观察与结局指标包括入院后达到创面愈合所需的手术次数、创面愈合后的复发率、围手术期并发症(肺部感染、严重心血管事件、静脉血栓栓塞症、脑卒中及谵妄等)的发生率、患者满意度评分等。结果:MDT讨论组患者189例,非MDT讨论组患者267例,两组患者的年龄、性别、体重指数、美国麻醉医师协会(American Society of Anesthesiologists,ASA)分级、合并症、慢性难愈合创面的病因与部位等临床资料差异无统计学意义(P>0.05)。MDT讨论组与非MDT讨论组患者获得创面愈合所需的平均手术次数分别为(2.1±1.1)次与(2.8±1.6)次,差异有统计学意义(P<0.001),这种差异在糖尿病溃疡、外伤或手术后感染、放疗后不愈合等3个病因造成的慢性难愈合创面中也有统计学意义(P<0.05)。非MDT讨论组患者在创面痊愈后的复发率是18.0%,稍高于MDT讨论组的14.3%,但差异无统计学意义(P>0.05)。在围手术期并发症方面,非MDT讨论组的发生率也较MDT讨论组高(3.7%vs.2.6%),但差异无统计学意义(P>0.05)。患者满意度方面,MDT讨论组的评分显著高于非MDT讨论组,差异有统计学意义(96.5 vs.91.1,P=0.028)。结论:多学科诊疗模式能够显著减少慢性难愈合创面患者的住院手术次数,提升治愈效率,提高患者满意度,是优化慢性难愈合创面临床诊疗成效的推荐模式。
