利用外观形貌分析、扫描电镜(scanning electron microscope,SEM)形貌分析、力学性能测试、化学成分分析及显微组织检测等方法,对断裂的循环水泵轴进行了系统失效分析。结果表明,该泵轴轴颈变截面加工不规范,根部存在车削凹槽,导致轴径...利用外观形貌分析、扫描电镜(scanning electron microscope,SEM)形貌分析、力学性能测试、化学成分分析及显微组织检测等方法,对断裂的循环水泵轴进行了系统失效分析。结果表明,该泵轴轴颈变截面加工不规范,根部存在车削凹槽,导致轴径变截面产生较大应力集中。泵轴加工阶段未进行调质处理,泵体金相组织为网状铁素体+珠光体,致使材料强度及韧性下降,对裂纹敏感性显著上升。在运行过程中,裂纹在轴颈变截面处的车削凹槽(应力集中区)萌生,以疲劳裂纹形式扩展,最终引发泵轴发生高周低应力疲劳断裂。建议优化轴颈变截面过渡结构,加强对循环水泵轴热加工与热处理的验收控制,选用组织与性能良好、力学性能合格的泵轴材料,并在运行过程中加强对因机组负荷频繁变化引发的轴体损伤检查,避免类似断裂失效故障再次发生。展开更多
目的比较鼻内镜辅助下低温等离子技术与传统唇龈沟入路在鼻前庭囊肿手术中的疗效。方法收集2013年1月-2016年11月在右江民族医学院附属医院耳鼻咽喉头颈外科收住的鼻前庭囊肿患者共38例,分为对照组20例和实验组18例,对照组采用唇龈沟入...目的比较鼻内镜辅助下低温等离子技术与传统唇龈沟入路在鼻前庭囊肿手术中的疗效。方法收集2013年1月-2016年11月在右江民族医学院附属医院耳鼻咽喉头颈外科收住的鼻前庭囊肿患者共38例,分为对照组20例和实验组18例,对照组采用唇龈沟入路手术,实验组采用鼻内镜辅助下低温等离子消融,比较两组患者手术时间、术中出血量、术后住院时间、术后并发症以及复发情况等。结果实验组与对照组比较,平均手术时间减少[(65.45±27.51)vs(34.72±17.61)min,P=0.000]、术中出血量减少[(22.35±18.41)vs(3.17±1.69)ml,P=0.000]、术后住院时间缩短[(6.35±0.75)vs(3.61±1.19)d,P=0.000]和术后并发症减少(16 vs 1,P=0.000),两组复发情况差异无统计学意义(1 vs 0,P=0.783)。结论鼻内镜辅助下低温等离子技术治疗鼻前庭囊肿相对于传统唇龈沟入路,具有时间短、创伤小、恢复快、操作简单和疗效好的优势,值得推广。展开更多
AIM:To investigate the causal relationship between dietary intake and myopia using Mendelian randomization(MR)analysis.METHODS:Genome-wide association study(GWAS)data from the IEU Open GWAS database were utilized to e...AIM:To investigate the causal relationship between dietary intake and myopia using Mendelian randomization(MR)analysis.METHODS:Genome-wide association study(GWAS)data from the IEU Open GWAS database were utilized to examine associations between myopia and various dietary factors.MR analysis,incorporating both univariable and multivariable approaches,assessed the impact of food intake on myopia risk through five analytical methods,with inverse variance weighted(IVW)serving as the primary reference.Sensitivity analyses,including heterogeneity assessment,horizontal pleiotropy evaluation,and leave-oneout analysis,were conducted to validate the MR findings.RESULTS:Univariable MR analysis identified a causal link between food intake and myopia.Consumption of breaded fish,canned soup,sweet biscuits,and certain fruits correlated with a lower risk of myopia,whereas intake of low-calorie hot chocolate and cereal was associated with an increased risk.Multivariable MR analysis further confirmed that breaded fish consumption exerted a direct protective effect against myopia,particularly when consumed alongside other dietary components.These findings highlight the intricate interplay between specific dietary factors and myopia development,offering valuable insights for further research.CONCLUSION:MR analysis provides evidence supporting a potential causal relationship between breaded fish intake and myopia,underscoring its relevance in targeted myopia prevention strategies.展开更多
Background:Oral squamous cell carcinoma(OSCC)is the most common head and neck malig-nancy with a low five-year survival rate.ATP-binding cassette subfamily B member 5(ABCB5)has been linked to tumorigenesis.However,its...Background:Oral squamous cell carcinoma(OSCC)is the most common head and neck malig-nancy with a low five-year survival rate.ATP-binding cassette subfamily B member 5(ABCB5)has been linked to tumorigenesis.However,its role in inducing OSCC remains unclear.Methods:Quantitative reverse transcription polymerase chain reaction(qRT-PCR),western blot,and immunocytochemistry(ICC)were performed to examine the level of ABCB5 in OSCC(CAL27 and HSC-3)and human oral keratinocyte(HOK).ABCB5 was knocked down in CAL27 cells using ABCB5-specific small interfering RNA(ABCB5 siRNA),and its contribution to migration,invasion,and epithelial-mesenchymal transition(EMT),a process by which epithelial cells lose their tight junction and acquire an increased migratory and invasive phenotype resembling that of mesenchymal cells,were evaluated by three-dimension and transwell migration and invasion assays,qRT-PCR and ICC.An in vivo OSCC model was established using 4-nitroquinoline-1-oxide(4NQO),a carcinogenic chemical that is commonly used to develop OSCC by destroying DNA synthesis and oxidative stress.Pathological alterations,ABCB5,and EMT markers were evaluated by H&E staining,immunohistochemistry,and qRT-PCR.Results:ABCB5 was significantly upregulated in CAL27 and HSC-3 cells as compared to HOK.Knockdown of ABCB5 significantly reduced the number of migrated and invaded CAL27 cells,accompanied by the significantly increased E-cadherin and decreased Vimentin and N-cadherin under Transforming growth factorβ(TGF-β)treatment.In vivo,as OSCC advanced,a notable rise in the expressions of ABCB5,N-cadherin,and Vimentin,while a statistical decrease in E-cadherin was demonstrated.Conclusion:ABCB5 promotes the migration,invasion,and EMT of OSCC.ABCB5 might be a new biomarker and potential therapeutic target for OSCC.展开更多
In this study,we consider a single-link flexible manipulator in the presence of an unknown Bouc-Wen type of hysteresis and intermittent actuator faults.First,an inverse hysteresis dynamics model is introduced,and then...In this study,we consider a single-link flexible manipulator in the presence of an unknown Bouc-Wen type of hysteresis and intermittent actuator faults.First,an inverse hysteresis dynamics model is introduced,and then the control input is divided into an expected input and an error compensator.Second,a novel adaptive neural network-based control scheme is proposed to cancel the unknown input hysteresis.Subsequently,by modifying the adaptive laws and local control laws,a fault-tolerant control strategy is applied to address uncertain intermittent actuator faults in a flexible manipulator system.Through the direct Lyapunov theory,the proposed scheme allows the state errors to asymptotically converge to a specified interval.Finally,the effectiveness of the proposed scheme is verified through numerical simulations and experiments.展开更多
Mg alloys with a combination of high strength and excellent ductility are increasingly required for structural applications.This study investigates the influence of advanced processing techniques on the mechanical pro...Mg alloys with a combination of high strength and excellent ductility are increasingly required for structural applications.This study investigates the influence of advanced processing techniques on the mechanical properties and microstructural evolution of Mg-Gd-Y-Zn-Zr alloys.Utilizing a combination of double extrusion and stepwise hot rolling followed by aging treatments,significant enhancements in the mechanical performance of these alloys are demonstrated.The processing techniques applied lead to notable refinement in grain-size and modifications in the microstructure,including the transformation of LPSO phases from 18R to 24R and the dispersion of β phase particles.These microstructural transformations contribute to a substantial increase in yield-strength,ultimate-tensile-strength,and ductility.Furthermore,findings reveal that these improvements are also supported by alterations in material texture,which influence dislocation dynamics as indicated by changes in Kernel Average Misorientation(KAM)values.The combined effect of grain boundary(GB)strengthening,phase distribution,and texture modification elucidates the observed mechanical enhancements.This research provides valuable insights into the design and optimization of Mg-Gd-Y-Zn-Zr alloys for critical applications in aerospace and automotive industries where high strength and ductility are paramount.展开更多
In this paper,a novel data-driven bipartite consensus control scheme is proposed for the rotation problem of large workpieces with multi-robot systems(MRSs)under a directed communication topology.The rotation of a lar...In this paper,a novel data-driven bipartite consensus control scheme is proposed for the rotation problem of large workpieces with multi-robot systems(MRSs)under a directed communication topology.The rotation of a large workpiece is described as the MRSs with cooperation and antagonism interaction.By the signed graph theory,it is further transformed into a bipartite consensus control problem,where all followers are uniformly degenerated into the general nonlinear systems based on the lateral error model.To augment the flexibility of control protocol and improve control performance,a higher-dimensional full form dynamic linearization(FFDL)technique is committed to the MRSs.The control input criterion function consists of the data model based on FFDL and the bipartite consensus error based on the signed graph theory,and the proposed control protocol is given by optimizing this criterion function.In this way,this scheme has a higher degree of freedom and better adaptive adjustment capability while not excessively increasing the control method complexity,and it can also be compatible with other forms of dynamic linearization techniques in MRSs.Further,three matrix norm lemmas are introduced to deal with the challenges of stability analysis caused by higher matrix dimensions and more robots.Finally,the effectiveness of the proposed method is verified by numerical simulations.展开更多
Dear Editor,The role of the microbiota-gut-brain axis in Parkinson’s disease(PD)has garnered increasing att ention[1].Among the various empirical subtype systems of PD,motor subtype classifi cation into tremor-domina...Dear Editor,The role of the microbiota-gut-brain axis in Parkinson’s disease(PD)has garnered increasing att ention[1].Among the various empirical subtype systems of PD,motor subtype classifi cation into tremor-dominant(TD)and postural instability and gait diffi culty(PIGD)is the most commonly utilized[2].However,the relationship between gut microbiota and clinical subtypes of PD remains unclear.展开更多
文摘利用外观形貌分析、扫描电镜(scanning electron microscope,SEM)形貌分析、力学性能测试、化学成分分析及显微组织检测等方法,对断裂的循环水泵轴进行了系统失效分析。结果表明,该泵轴轴颈变截面加工不规范,根部存在车削凹槽,导致轴径变截面产生较大应力集中。泵轴加工阶段未进行调质处理,泵体金相组织为网状铁素体+珠光体,致使材料强度及韧性下降,对裂纹敏感性显著上升。在运行过程中,裂纹在轴颈变截面处的车削凹槽(应力集中区)萌生,以疲劳裂纹形式扩展,最终引发泵轴发生高周低应力疲劳断裂。建议优化轴颈变截面过渡结构,加强对循环水泵轴热加工与热处理的验收控制,选用组织与性能良好、力学性能合格的泵轴材料,并在运行过程中加强对因机组负荷频繁变化引发的轴体损伤检查,避免类似断裂失效故障再次发生。
文摘目的比较鼻内镜辅助下低温等离子技术与传统唇龈沟入路在鼻前庭囊肿手术中的疗效。方法收集2013年1月-2016年11月在右江民族医学院附属医院耳鼻咽喉头颈外科收住的鼻前庭囊肿患者共38例,分为对照组20例和实验组18例,对照组采用唇龈沟入路手术,实验组采用鼻内镜辅助下低温等离子消融,比较两组患者手术时间、术中出血量、术后住院时间、术后并发症以及复发情况等。结果实验组与对照组比较,平均手术时间减少[(65.45±27.51)vs(34.72±17.61)min,P=0.000]、术中出血量减少[(22.35±18.41)vs(3.17±1.69)ml,P=0.000]、术后住院时间缩短[(6.35±0.75)vs(3.61±1.19)d,P=0.000]和术后并发症减少(16 vs 1,P=0.000),两组复发情况差异无统计学意义(1 vs 0,P=0.783)。结论鼻内镜辅助下低温等离子技术治疗鼻前庭囊肿相对于传统唇龈沟入路,具有时间短、创伤小、恢复快、操作简单和疗效好的优势,值得推广。
基金Supported by Xi’an Science and Technology Program Project(No.24YXYJ0108)Support Projects of Xi’an Children’s Hospital(No.2024I07).
文摘AIM:To investigate the causal relationship between dietary intake and myopia using Mendelian randomization(MR)analysis.METHODS:Genome-wide association study(GWAS)data from the IEU Open GWAS database were utilized to examine associations between myopia and various dietary factors.MR analysis,incorporating both univariable and multivariable approaches,assessed the impact of food intake on myopia risk through five analytical methods,with inverse variance weighted(IVW)serving as the primary reference.Sensitivity analyses,including heterogeneity assessment,horizontal pleiotropy evaluation,and leave-oneout analysis,were conducted to validate the MR findings.RESULTS:Univariable MR analysis identified a causal link between food intake and myopia.Consumption of breaded fish,canned soup,sweet biscuits,and certain fruits correlated with a lower risk of myopia,whereas intake of low-calorie hot chocolate and cereal was associated with an increased risk.Multivariable MR analysis further confirmed that breaded fish consumption exerted a direct protective effect against myopia,particularly when consumed alongside other dietary components.These findings highlight the intricate interplay between specific dietary factors and myopia development,offering valuable insights for further research.CONCLUSION:MR analysis provides evidence supporting a potential causal relationship between breaded fish intake and myopia,underscoring its relevance in targeted myopia prevention strategies.
基金the financial support from the Sichuan Science and Technology Program(No.2024JDRC0040)Luzhou Science and Technology Program(No.2023JYJ002,No.2023SYF139)+4 种基金Southwest Medical University Technology Program(No.2024ZKY018,No.2023ZD001,No.2024KQZX09)National Natural Science Foundation of China(No.82403404)NHCKey Laboratory ofNuclear TechnologyMedical Transformation(Mianyang Central Hospital)(No.2023HYX028)The Science and Technology Strategic Cooperation Programs of Deyang Stomatological Hospital and Southwest Medical University(No.2024DYKQXNYD03)the Affiliated Stomatology Hospital of Southwest Medical University Program(No.2022KQ03)。
文摘Background:Oral squamous cell carcinoma(OSCC)is the most common head and neck malig-nancy with a low five-year survival rate.ATP-binding cassette subfamily B member 5(ABCB5)has been linked to tumorigenesis.However,its role in inducing OSCC remains unclear.Methods:Quantitative reverse transcription polymerase chain reaction(qRT-PCR),western blot,and immunocytochemistry(ICC)were performed to examine the level of ABCB5 in OSCC(CAL27 and HSC-3)and human oral keratinocyte(HOK).ABCB5 was knocked down in CAL27 cells using ABCB5-specific small interfering RNA(ABCB5 siRNA),and its contribution to migration,invasion,and epithelial-mesenchymal transition(EMT),a process by which epithelial cells lose their tight junction and acquire an increased migratory and invasive phenotype resembling that of mesenchymal cells,were evaluated by three-dimension and transwell migration and invasion assays,qRT-PCR and ICC.An in vivo OSCC model was established using 4-nitroquinoline-1-oxide(4NQO),a carcinogenic chemical that is commonly used to develop OSCC by destroying DNA synthesis and oxidative stress.Pathological alterations,ABCB5,and EMT markers were evaluated by H&E staining,immunohistochemistry,and qRT-PCR.Results:ABCB5 was significantly upregulated in CAL27 and HSC-3 cells as compared to HOK.Knockdown of ABCB5 significantly reduced the number of migrated and invaded CAL27 cells,accompanied by the significantly increased E-cadherin and decreased Vimentin and N-cadherin under Transforming growth factorβ(TGF-β)treatment.In vivo,as OSCC advanced,a notable rise in the expressions of ABCB5,N-cadherin,and Vimentin,while a statistical decrease in E-cadherin was demonstrated.Conclusion:ABCB5 promotes the migration,invasion,and EMT of OSCC.ABCB5 might be a new biomarker and potential therapeutic target for OSCC.
基金supported in part by the National Key Research and Development Program of China(2023YFB4706400)the National Natural Science Foundation of China(62273112,62073030,62203161)+6 种基金the Guangdong Basic and Applied Basic Research Foundation(2023B1515120018,2023B1515120019)the Open Project of Xiangjiang Laboratory(23XJ03012)the Natural Science Foundation of Hunan Province(2024JJ5087)the Natural Science Foundation of Jiangxi Province(20232BAB212024)the National Research Foundation of Korea funded by the Ministry of Science and ICT,South Korea(IRIS-2023-00207954)the Science and Technology Planning Project of Guangzhou,China(2023A03J0120)the Guangzhou University Research Project(RC2023037)
文摘In this study,we consider a single-link flexible manipulator in the presence of an unknown Bouc-Wen type of hysteresis and intermittent actuator faults.First,an inverse hysteresis dynamics model is introduced,and then the control input is divided into an expected input and an error compensator.Second,a novel adaptive neural network-based control scheme is proposed to cancel the unknown input hysteresis.Subsequently,by modifying the adaptive laws and local control laws,a fault-tolerant control strategy is applied to address uncertain intermittent actuator faults in a flexible manipulator system.Through the direct Lyapunov theory,the proposed scheme allows the state errors to asymptotically converge to a specified interval.Finally,the effectiveness of the proposed scheme is verified through numerical simulations and experiments.
基金financially supported by the financial supports from the National Natural Science Foundation of China(Grant No.52027805).
文摘Mg alloys with a combination of high strength and excellent ductility are increasingly required for structural applications.This study investigates the influence of advanced processing techniques on the mechanical properties and microstructural evolution of Mg-Gd-Y-Zn-Zr alloys.Utilizing a combination of double extrusion and stepwise hot rolling followed by aging treatments,significant enhancements in the mechanical performance of these alloys are demonstrated.The processing techniques applied lead to notable refinement in grain-size and modifications in the microstructure,including the transformation of LPSO phases from 18R to 24R and the dispersion of β phase particles.These microstructural transformations contribute to a substantial increase in yield-strength,ultimate-tensile-strength,and ductility.Furthermore,findings reveal that these improvements are also supported by alterations in material texture,which influence dislocation dynamics as indicated by changes in Kernel Average Misorientation(KAM)values.The combined effect of grain boundary(GB)strengthening,phase distribution,and texture modification elucidates the observed mechanical enhancements.This research provides valuable insights into the design and optimization of Mg-Gd-Y-Zn-Zr alloys for critical applications in aerospace and automotive industries where high strength and ductility are paramount.
基金supported in part by the National Natural Science Foundation of China(62473142,62203161)Special Funding Support for the Construction of Innovative Provinces in Hunan Province(2021GK1010)+1 种基金Guangdong Basic and Applied Basic Research Foundation(2024A1515011579),Project of State Key Laboratory of Advanced Design and Manufacturing Technology for Vehicle(72275007).
文摘In this paper,a novel data-driven bipartite consensus control scheme is proposed for the rotation problem of large workpieces with multi-robot systems(MRSs)under a directed communication topology.The rotation of a large workpiece is described as the MRSs with cooperation and antagonism interaction.By the signed graph theory,it is further transformed into a bipartite consensus control problem,where all followers are uniformly degenerated into the general nonlinear systems based on the lateral error model.To augment the flexibility of control protocol and improve control performance,a higher-dimensional full form dynamic linearization(FFDL)technique is committed to the MRSs.The control input criterion function consists of the data model based on FFDL and the bipartite consensus error based on the signed graph theory,and the proposed control protocol is given by optimizing this criterion function.In this way,this scheme has a higher degree of freedom and better adaptive adjustment capability while not excessively increasing the control method complexity,and it can also be compatible with other forms of dynamic linearization techniques in MRSs.Further,three matrix norm lemmas are introduced to deal with the challenges of stability analysis caused by higher matrix dimensions and more robots.Finally,the effectiveness of the proposed method is verified by numerical simulations.
基金supported in part by the Jiangsu Provincial Geriatric Health Research Project(LK2021049)the Jiangsu Provincial Geriatric Health Research Project(LKM2023044)the Huai’an Key Laboratory of Aging and Geriatric Syndrome Research(HAP202105).
文摘Dear Editor,The role of the microbiota-gut-brain axis in Parkinson’s disease(PD)has garnered increasing att ention[1].Among the various empirical subtype systems of PD,motor subtype classifi cation into tremor-dominant(TD)and postural instability and gait diffi culty(PIGD)is the most commonly utilized[2].However,the relationship between gut microbiota and clinical subtypes of PD remains unclear.
