类淋巴系统(glymphatic system,GS)是大脑中废物清除的途径,其功能受损可以通过沿血管周围间隙扩散张量成像分析(diffusion tensor imaging analysis along the perivascular space,DTI-ALPS)进行评估。目前,DTI-ALPS作为一种非侵入性...类淋巴系统(glymphatic system,GS)是大脑中废物清除的途径,其功能受损可以通过沿血管周围间隙扩散张量成像分析(diffusion tensor imaging analysis along the perivascular space,DTI-ALPS)进行评估。目前,DTI-ALPS作为一种非侵入性方法已被广泛用于评估神经系统疾病中的GS功能改变,它在评估神经系统疾病的病程进展、认知障碍及预测预后等方面发挥了举足轻重的作用。本文就GS、DTI-ALPS方法与应用优势及其在神经系统疾病中的应用进行综述,旨在为神经系统疾病的病程进展、预测影响预后因素以及临床治疗疗效方面提供一定的参考。展开更多
类淋巴系统(glymphatic system,GS)是近年出现的探究中枢神经系统疾病生理病理机制的新兴角度。研究证实沿血管周围间隙扩散张量分析(diffusion tensor image analysis along the perivascular space,DTI-ALPS)能够有效地评估中枢神经...类淋巴系统(glymphatic system,GS)是近年出现的探究中枢神经系统疾病生理病理机制的新兴角度。研究证实沿血管周围间隙扩散张量分析(diffusion tensor image analysis along the perivascular space,DTI-ALPS)能够有效地评估中枢神经系统疾病患者GS功能改变,尤其是在退行性中枢神经系统疾病,如癫痫、帕金森病、痴呆。本文就应用DTI-ALPS技术评估中枢神经系统疾病患者GS功能的研究现状作一综述,旨在为疾病的神经影像研究提供新方向。展开更多
The vibration pretreatment-microwave curing process is an efficient,low energy consumption,and high-quality out-of-autoclave curing process for carbon fiber resin matrix composites.This study aims to investigate the i...The vibration pretreatment-microwave curing process is an efficient,low energy consumption,and high-quality out-of-autoclave curing process for carbon fiber resin matrix composites.This study aims to investigate the impact of vibration pretreatment temperature on the fiber weight content,microscopic morphology and mechanical properties of the composite laminates by using optical digital microscopy,universal tensile testing machine and thermo-gravimetric analyzer.Additionally,the combined mode of Bragg fiber grating sensor and temperature measurement fiber was employed to explore the effect of vibration pretreatment on the strain process during microwave curing.The study results revealed that the change in vibration pretreatment temperature had a slight impact on the fiber weight content when the vibration acceleration remained constant.The metallographic and interlaminar strength of the specimen formed at a vibration pretreatment temperature of 80℃ demonstrated a porosity of 0.414% and a 10.69% decrease in interlaminar shear strength compared to autoclave curing.Moreover,the introduction of the vibration energy field during the microwave curing process led to a significant reduction in residual strain in both the 0°and 90°fiber directions,when the laminate was cooled to 60℃.展开更多
类淋巴系统可以清除脑内代谢废物,对维持中枢神经系统的内环境稳态起着重要作用,是学习、记忆等高级认知功能的重要基础。近来,越来越多的研究采用沿血管周围间隙弥散张量成像分析(diffusion tensor imaging analysis along the perivas...类淋巴系统可以清除脑内代谢废物,对维持中枢神经系统的内环境稳态起着重要作用,是学习、记忆等高级认知功能的重要基础。近来,越来越多的研究采用沿血管周围间隙弥散张量成像分析(diffusion tensor imaging analysis along the perivascular space,DTI-ALPS)方法评估类淋巴功能。相比其他需要荧光示踪技术或注射造影剂的有创检查,DTI-ALPS可以通过量化不同方向上水分子的弥散率对类淋巴系统进行流体力学评估,是一种无创的在体神经影像学方法。利用DTI-ALPS方法计算出的ALPS指数与中枢神经系统疾病及其他系统疾病的认知功能显著相关,并能反映疾病的动态变化。因此,ALPS指数有望成为预测疾病预后及临床干预疗效的新型神经影像学生物标志物。展开更多
文摘类淋巴系统(glymphatic system,GS)是大脑中废物清除的途径,其功能受损可以通过沿血管周围间隙扩散张量成像分析(diffusion tensor imaging analysis along the perivascular space,DTI-ALPS)进行评估。目前,DTI-ALPS作为一种非侵入性方法已被广泛用于评估神经系统疾病中的GS功能改变,它在评估神经系统疾病的病程进展、认知障碍及预测预后等方面发挥了举足轻重的作用。本文就GS、DTI-ALPS方法与应用优势及其在神经系统疾病中的应用进行综述,旨在为神经系统疾病的病程进展、预测影响预后因素以及临床治疗疗效方面提供一定的参考。
文摘类淋巴系统(glymphatic system,GS)是近年出现的探究中枢神经系统疾病生理病理机制的新兴角度。研究证实沿血管周围间隙扩散张量分析(diffusion tensor image analysis along the perivascular space,DTI-ALPS)能够有效地评估中枢神经系统疾病患者GS功能改变,尤其是在退行性中枢神经系统疾病,如癫痫、帕金森病、痴呆。本文就应用DTI-ALPS技术评估中枢神经系统疾病患者GS功能的研究现状作一综述,旨在为疾病的神经影像研究提供新方向。
基金Projects(52175373,52005516)supported by the National Natural Science Foundation of ChinaProject(2018YFA0702800)supported by the National Key Basic Research Program,ChinaProject(ZZYJKT2021-03)supported by the State Key Laboratory of High Performance Complex Manufacturing,Central South University,China。
文摘The vibration pretreatment-microwave curing process is an efficient,low energy consumption,and high-quality out-of-autoclave curing process for carbon fiber resin matrix composites.This study aims to investigate the impact of vibration pretreatment temperature on the fiber weight content,microscopic morphology and mechanical properties of the composite laminates by using optical digital microscopy,universal tensile testing machine and thermo-gravimetric analyzer.Additionally,the combined mode of Bragg fiber grating sensor and temperature measurement fiber was employed to explore the effect of vibration pretreatment on the strain process during microwave curing.The study results revealed that the change in vibration pretreatment temperature had a slight impact on the fiber weight content when the vibration acceleration remained constant.The metallographic and interlaminar strength of the specimen formed at a vibration pretreatment temperature of 80℃ demonstrated a porosity of 0.414% and a 10.69% decrease in interlaminar shear strength compared to autoclave curing.Moreover,the introduction of the vibration energy field during the microwave curing process led to a significant reduction in residual strain in both the 0°and 90°fiber directions,when the laminate was cooled to 60℃.
文摘[目的]由于FORAN V70 R2.0(及以上版本)输出的JT模型中存在很多同名的特征节点,导致采用间隙分析软件对其进行分析时时间消耗加大且间隙分析结果难以处理。针对该问题,[方法]在研究FORAN导出的JT文件装配结构和蕴含信息(几何信息、材料属性信息等)的基础上,提出一种特征节点合并算法。该算法由坐标变换、模型节点更名、节点几何数据移动和材料属性处理4个步骤构成。然后,利用C++及JT Open Toolkit实现所提出的算法。[结果]结果显示,利用该算法处理后的JT模型只包含1个装配节点且保留了原始JT模型的内在信息,可为后期间隙分析提供有效的输入数据。[结论]大量的实例验证了所提出算法的有效性,处理后的JT文件大小可减少7%~20%。
文摘类淋巴系统可以清除脑内代谢废物,对维持中枢神经系统的内环境稳态起着重要作用,是学习、记忆等高级认知功能的重要基础。近来,越来越多的研究采用沿血管周围间隙弥散张量成像分析(diffusion tensor imaging analysis along the perivascular space,DTI-ALPS)方法评估类淋巴功能。相比其他需要荧光示踪技术或注射造影剂的有创检查,DTI-ALPS可以通过量化不同方向上水分子的弥散率对类淋巴系统进行流体力学评估,是一种无创的在体神经影像学方法。利用DTI-ALPS方法计算出的ALPS指数与中枢神经系统疾病及其他系统疾病的认知功能显著相关,并能反映疾病的动态变化。因此,ALPS指数有望成为预测疾病预后及临床干预疗效的新型神经影像学生物标志物。
