SGMS2的致病性杂合突变会导致一种罕见的单基因骨质疏松症,称为颅骨环形病变伴骨脆性增加(calvarial doughnut lesions with bone fragility,CDL),伴或不伴有脊椎干骺端发育不良。SGMS2编码的鞘磷脂合酶2(sphingomyelin synthase 2,SMS2...SGMS2的致病性杂合突变会导致一种罕见的单基因骨质疏松症,称为颅骨环形病变伴骨脆性增加(calvarial doughnut lesions with bone fragility,CDL),伴或不伴有脊椎干骺端发育不良。SGMS2编码的鞘磷脂合酶2(sphingomyelin synthase 2,SMS2)参与鞘磷脂(sphingomyelin,SM)产生,SGMS2突变导致骨骼发育异常,提示SM代谢可能在骨代谢中发挥重要的作用。本文报告1例颅骨环形病变伴骨质疏松性骨折患者,使用全外显子组序检测发现其存在SGMS2基因c.148C>T(p.Arg50*)杂合突变。展开更多
Railway accidents,particularly serious derailments,can lead to catastrophic consequences.Therefore,it is essential to prevent derailment escalation to reduce the likelihood of severe derailments.Train post-derailment ...Railway accidents,particularly serious derailments,can lead to catastrophic consequences.Therefore,it is essential to prevent derailment escalation to reduce the likelihood of severe derailments.Train post-derailment behaviours and containment methods play a critical role in preventing derailment escalation and providing passive safety protection and accident prevention in the event of a derailment.However,despite the increasing attention on this field from academia and industry in recent years,there is a lack of systematic exploration and summarization of emerging applications and containment methods in train post-derailment research.For this reason,this paper presents a comprehensive review of existing studies on train post-derailment behaviours,encompassing various topics such as post-derailment contact-impact models,dynamic modelling and simulation techniques,and the primary factors influencing post-derailment behaviours.Significantly,this review introduces and elucidates substitute guidance mechanisms(SGMs),which serve as railway-specific passive safety protection and accident prevention measures.The various types of SGMs are depicted,and their ongoing developments and applications are explored in depth.The review additionally points out several unresolved challenges including the adverse effects of SGMs,and proposes future research directions to advance the theoretical understanding and practical application of train post-derailment behaviours and containment methods.This review seeks to be a valuable reference for railway industry professionals in preventing catastrophic derailment consequences through post-derailment containment methods.展开更多
This paper presents a method to study the free vibration of a plate with circular holes.The circular hole is regarded as a virtual small plate in which the mass density and Young's modulus are zero.Therefore,the f...This paper presents a method to study the free vibration of a plate with circular holes.The circular hole is regarded as a virtual small plate in which the mass density and Young's modulus are zero.Therefore,the free vibration problem of the circular hole plate can be transformed into the free vibration problem of the equivalent rectangular plate with non-uniform thickness.The model is derived from the spectral geometry method(SGM),and the displacement of the plate with circular holes is expanded by the modified Fourier series.Virtual springs are added to the boundary of the plate to simulate the boundary conditions of simply supported and fixed supports.The accuracy of this method is verified by comparison with the finite element calculation results.The relationship between modal numerical solutions of plates with circular holes and boundary conditions and geometry of the plate is studied.展开更多
针对传统数字真正射影像(True Digital Orthophoto Map,TDOM)生产存在处理流程复杂、效率低、质量差、精度低的问题,基于无人机航空倾斜摄影测量的影像数据,通过INPHO全数字航空遥感摄影测量软件,制定了从空三加密处理、到高精度数字表...针对传统数字真正射影像(True Digital Orthophoto Map,TDOM)生产存在处理流程复杂、效率低、质量差、精度低的问题,基于无人机航空倾斜摄影测量的影像数据,通过INPHO全数字航空遥感摄影测量软件,制定了从空三加密处理、到高精度数字表面模型(Digital Surface Model,DSM)创建,再到数字真正射影像成果生成的全新真正射影像生产流程。通过实际项目数据验证可知,此方法所生产的数字真正射影像精度高、质量好,且较传统方法流程简单、高自动化处理、效率高,为数字真正射影像生产提供了有效的应用方案。展开更多
文摘SGMS2的致病性杂合突变会导致一种罕见的单基因骨质疏松症,称为颅骨环形病变伴骨脆性增加(calvarial doughnut lesions with bone fragility,CDL),伴或不伴有脊椎干骺端发育不良。SGMS2编码的鞘磷脂合酶2(sphingomyelin synthase 2,SMS2)参与鞘磷脂(sphingomyelin,SM)产生,SGMS2突变导致骨骼发育异常,提示SM代谢可能在骨代谢中发挥重要的作用。本文报告1例颅骨环形病变伴骨质疏松性骨折患者,使用全外显子组序检测发现其存在SGMS2基因c.148C>T(p.Arg50*)杂合突变。
基金support from the National Natural Science Foundation of China (No.52172407 and No.U19A20110)the Natural Science Foundation of Sichuan Province (No.2022NSFSC0415).
文摘Railway accidents,particularly serious derailments,can lead to catastrophic consequences.Therefore,it is essential to prevent derailment escalation to reduce the likelihood of severe derailments.Train post-derailment behaviours and containment methods play a critical role in preventing derailment escalation and providing passive safety protection and accident prevention in the event of a derailment.However,despite the increasing attention on this field from academia and industry in recent years,there is a lack of systematic exploration and summarization of emerging applications and containment methods in train post-derailment research.For this reason,this paper presents a comprehensive review of existing studies on train post-derailment behaviours,encompassing various topics such as post-derailment contact-impact models,dynamic modelling and simulation techniques,and the primary factors influencing post-derailment behaviours.Significantly,this review introduces and elucidates substitute guidance mechanisms(SGMs),which serve as railway-specific passive safety protection and accident prevention measures.The various types of SGMs are depicted,and their ongoing developments and applications are explored in depth.The review additionally points out several unresolved challenges including the adverse effects of SGMs,and proposes future research directions to advance the theoretical understanding and practical application of train post-derailment behaviours and containment methods.This review seeks to be a valuable reference for railway industry professionals in preventing catastrophic derailment consequences through post-derailment containment methods.
基金supported by the National Natural Science Foundation of China(No.51805341)the Science and Technology Major Project of Ningbo City(No.2021Z098)。
文摘This paper presents a method to study the free vibration of a plate with circular holes.The circular hole is regarded as a virtual small plate in which the mass density and Young's modulus are zero.Therefore,the free vibration problem of the circular hole plate can be transformed into the free vibration problem of the equivalent rectangular plate with non-uniform thickness.The model is derived from the spectral geometry method(SGM),and the displacement of the plate with circular holes is expanded by the modified Fourier series.Virtual springs are added to the boundary of the plate to simulate the boundary conditions of simply supported and fixed supports.The accuracy of this method is verified by comparison with the finite element calculation results.The relationship between modal numerical solutions of plates with circular holes and boundary conditions and geometry of the plate is studied.
