焦虑性抑郁障碍(anxious major depressive disorder,AMDD)是抑郁症的一种重要亚型,AMDD有着更频繁的抑郁发作、更严重的症状、更差的治疗反应和结局以及更高比例的自杀企图,但其神经生物机制尚未完全明确。目前AMDD患者大脑结构改变多...焦虑性抑郁障碍(anxious major depressive disorder,AMDD)是抑郁症的一种重要亚型,AMDD有着更频繁的抑郁发作、更严重的症状、更差的治疗反应和结局以及更高比例的自杀企图,但其神经生物机制尚未完全明确。目前AMDD患者大脑结构改变多集中于前额叶、纹状体等灰质区域以及钩束、上纵束、胼胝体等部分白质纤维束;脑功能改变主要位于默认模式网络、执行网络、认知控制网络、突显网络、边缘系统;上述脑区改变与AMDD情绪、认知、执行等功能障碍密切相关。未来的研究应该努力减少临床异质性,明确疾病的定义,拓展关键脑区的研究。文章分别从结构磁共振和功能磁共振成像角度系统综述了AMDD的脑结构与功能改变,促进了对AMDD神经生物学机制的理解,并为疾病的早期识别和开发新的有效的治疗方案提供强有力的证据。展开更多
The continuum approach in fluid flow modeling is generally applied to porous geological media, but has limited applicability to fractured rocks. With the presence of a discrete fracture network relatively sparsely dis...The continuum approach in fluid flow modeling is generally applied to porous geological media, but has limited applicability to fractured rocks. With the presence of a discrete fracture network relatively sparsely distributed in the matrix, it may be difficult or erroneous to use a porous medium fluid flow model with continuum assumptions to describe the fluid flow in fractured rocks at small or even large field scales. A discrete fracture fluid flow approach incorporating a stochastic fracture network with numerical fluid flow simulations could have the capability of capturing fluid flow behaviors such as inhomogeneity and anisotropy while reflecting the changes of hydraulic features at different scales. Moreover, this approach can be implemented to estimate the size of the representative elementary volume (REV) in order to find out the scales at which a porous medium flow model could be applied, and then to determine the hydraulic conductivity tensor for fractured rocks. The following topics are focused on in this study: (a) conceptual discrete fracture fluid flow modeling incorporating a stochastic fracture network with numerical flow simulations; (b) estimation of REV and hydraulic conductivity tensor for fractured rocks utilizing a stochastic fracture network with numerical fluid flow simulations; (c) investigation of the effect of fracture orientation and density on the hydraulic conductivity and REV by implementing a stochastic fracture network with numerical fluid flow simulations, and (d) fluid flow conceptual models accounting for major and minor fractures in the 2 D or 3 D flow fields incorporating a stochastic fracture network with numerical fluid flow simulations.展开更多
Background： This study aimed to observe the differences in brain gray matter volume in drug-naive female patients after the first episode of major depression with and without stressful life events （SLEs） before the...Background： This study aimed to observe the differences in brain gray matter volume in drug-naive female patients after the first episode of major depression with and without stressful life events （SLEs） before the onset of depression.Methods： Forty-three drug-naive female patients voluntarily participated in the present study after the first major depressive episode.The life event scale was used to evaluate the severity of the impact of SLEs during 6 months before the onset of the major depressive episode.High-field magnetic resonance imaging （MRI） scans were obtained, and the VBM and SPM8 software process were used to process and analyze the MRI.Results： Compared to that in patients without SLEs, the volume of brain gray matter was lower in the bilateral temporal lobe, right occipital lobe, and right limbic lobe in the SLE group.However, the gray matter volume did not differ significantly between the two groups after the application of false discovery rate （FDR） correction.Conclusions： Although the results of the present study suggest the absence of significant differences in brain gray matter volume between female drug-naive patients after the first episode of major depression with and without SLEs after FDR correction, the study provides useful information for exploring the definitive role of stress in the onset of depression.展开更多
基金supported by the National Natural Science Foundation of China(81371490)the Zhejiang Province Health and Science Key Project(2015ZDA016)+2 种基金the Science and Technology Development Plan Project of Hangzhou Municip ality(number 20160533B57)the Medical and Health Science and Technology Plan Project of Hangzhou Municip ality(number 2015A56)the Medical and Health Science and Technology Plan Project of Zhejiang Province(number 2017185411)
文摘焦虑性抑郁障碍(anxious major depressive disorder,AMDD)是抑郁症的一种重要亚型,AMDD有着更频繁的抑郁发作、更严重的症状、更差的治疗反应和结局以及更高比例的自杀企图,但其神经生物机制尚未完全明确。目前AMDD患者大脑结构改变多集中于前额叶、纹状体等灰质区域以及钩束、上纵束、胼胝体等部分白质纤维束;脑功能改变主要位于默认模式网络、执行网络、认知控制网络、突显网络、边缘系统;上述脑区改变与AMDD情绪、认知、执行等功能障碍密切相关。未来的研究应该努力减少临床异质性,明确疾病的定义,拓展关键脑区的研究。文章分别从结构磁共振和功能磁共振成像角度系统综述了AMDD的脑结构与功能改变,促进了对AMDD神经生物学机制的理解,并为疾病的早期识别和开发新的有效的治疗方案提供强有力的证据。
基金ChinaCommitteeofEducation theUniver sityofArizonaandtheMetropolitanWaterDistrictofSouthernCaliforni a.
文摘The continuum approach in fluid flow modeling is generally applied to porous geological media, but has limited applicability to fractured rocks. With the presence of a discrete fracture network relatively sparsely distributed in the matrix, it may be difficult or erroneous to use a porous medium fluid flow model with continuum assumptions to describe the fluid flow in fractured rocks at small or even large field scales. A discrete fracture fluid flow approach incorporating a stochastic fracture network with numerical fluid flow simulations could have the capability of capturing fluid flow behaviors such as inhomogeneity and anisotropy while reflecting the changes of hydraulic features at different scales. Moreover, this approach can be implemented to estimate the size of the representative elementary volume (REV) in order to find out the scales at which a porous medium flow model could be applied, and then to determine the hydraulic conductivity tensor for fractured rocks. The following topics are focused on in this study: (a) conceptual discrete fracture fluid flow modeling incorporating a stochastic fracture network with numerical flow simulations; (b) estimation of REV and hydraulic conductivity tensor for fractured rocks utilizing a stochastic fracture network with numerical fluid flow simulations; (c) investigation of the effect of fracture orientation and density on the hydraulic conductivity and REV by implementing a stochastic fracture network with numerical fluid flow simulations, and (d) fluid flow conceptual models accounting for major and minor fractures in the 2 D or 3 D flow fields incorporating a stochastic fracture network with numerical fluid flow simulations.
基金grants from the China Postdoctoral Science Foundation funded project，the Development of Medical Science and Technology Project of Shandong Province，the Natural Science Foundation of Shandong Province，the science and technology fund of Tianjin Health Bureau
文摘Background： This study aimed to observe the differences in brain gray matter volume in drug-naive female patients after the first episode of major depression with and without stressful life events （SLEs） before the onset of depression.Methods： Forty-three drug-naive female patients voluntarily participated in the present study after the first major depressive episode.The life event scale was used to evaluate the severity of the impact of SLEs during 6 months before the onset of the major depressive episode.High-field magnetic resonance imaging （MRI） scans were obtained, and the VBM and SPM8 software process were used to process and analyze the MRI.Results： Compared to that in patients without SLEs, the volume of brain gray matter was lower in the bilateral temporal lobe, right occipital lobe, and right limbic lobe in the SLE group.However, the gray matter volume did not differ significantly between the two groups after the application of false discovery rate （FDR） correction.Conclusions： Although the results of the present study suggest the absence of significant differences in brain gray matter volume between female drug-naive patients after the first episode of major depression with and without SLEs after FDR correction, the study provides useful information for exploring the definitive role of stress in the onset of depression.
