中原城市群的功能联系与结构的有序升级

基于历史、区位、交通、资源、产业基础等原因，分析了中原城市群内城市间功能联系的现状；借鉴国内其他城市群发展和经济全球化的发展趋势；提出了中原城市群城市功能结构的特点及其存在的问题；并参照中地论、极化—涓滴理论、规模—顺序法则、比较利益原理等城镇发展论提出了中原城市群结构有序升级的措施。  

完全分配的拓扑共生格的连通性

本文研究了完全分配的拓扑共生格的连通性.得到了下列主要结果:①若 F:(L_1,S_1) →(L_2,S_2) 是(S_1,S_2) 连续序同志(函数),且 D∈L_1是 S_1-连通元,则 F(D)是 S_(2-)连通元;②在(L_1S)中,若 C 是 S-连通元,且(C≤D≤■,则 D 是 S-连通元:③若{(L_1、 S_1) |i∈I}是一族完全分配的拓扑共生格,则■_I(L_i,S_1) 是连通的■■i∈I,(L_i,S_i)是连通的.  

任务背景下腹侧注意功能网络的fMRI研究

基于静息状态的功能磁共振成像(functional MRI,fMRI)已经成为当前人脑功能研究的重要手段之一,本研究采用任务背景来获取一种更为"纯净"的静息状态,其中脑区的"任务背景"被定义为那些不会激活感兴趣脑区的任务.由于到目前为止还不清楚在"任务背景"下人脑除默认网络外的其他"高级"功能网络内部是否被中断,本文研究了人脑听觉背景下腹侧注意网络内部的功能连接.结果表明在听觉背景下该网络内部存在显著的功能连接,这一结果说明简单的感觉任务不会中断人脑的腹侧注意网络.本研究首次证明在任务背景下,除默认网络之外,人脑还有一些高级功能网络内部存在显著功能连接.  

脑功能磁共振成像研究及应用展望

功能性核磁共振成像 (fMRI)技术可以显示大脑各个区域内静脉毛细血管中血液氧合状态所起的磁共振信号的微小变化 .fMRI作为无损和动态的探测技术 ,已日益成为观察大脑活动 ,进而揭示脑和思维关系的一种重要方法 .本文对功能磁共振成像的生物物理机制作了简要的描述 .然后分别介绍了脑高级功能磁共振成像研究过程中的实验设计、数据处理等环节 .最后给予了脑高级功能磁共振成像研究的最新进展和应用展望 .  

B P神经元控制器仿真

ＢＰ神经元网络具有很强的自适应、自学习和映射能力．本文对ＢＰ神经元拄制系统进行了仿真．整个仿真过程是在ＢｏｒｌａｎｄＣ＋＋２．０环境下实现的，控制算法程序具有较高的效率、扩充性和维护性．  

超越整函数半群的Julia集的连通性

考察了由一族超越整函数生成的半群的的动力学性质,其中半群运算是函数的复合。运用Fatou-Julia理论,研究了上述定义的半群的Julia集的连通性,得到上述定义的半群的Julia集在复平面内为连通的几个条件。同时,还给出了上述定义半群的Julia集并上无穷点在Riemann球面内为连通的两个条件。  

心智影像中功能联接对设计认知过程的影响

根据语义网络理论,提出心智影像中的功能联接对设计时间、设计质量、设计结果的创新性影响关系的3个理论假设,采用原案分析法对14名机械专业研究生进行可调座椅概念设计认知实验,以验证该假设的正确性,并采用Mann-Whitney非参数检验法进行统计分析.结果表明,心智影像中知识单元之间的功能联接越多,则设计时间越短,设计质量越高,设计结果越具有创新性,即假设都成立.  

自闭谱系障碍的大脑功能性连接研究进展

自闭谱系障碍是一种以早期社会交往上的广泛性异常、缺乏与人进行沟通的能力、异常局限的兴趣以及刻板重复性行为为特征的复杂的神经发育障碍.自闭谱系障碍的脑功能成像研究表明,无论是任务态下,还是静息态下,自闭谱系障碍存在着功能性连接的普遍降低,而这种神经同步性活动的异常可能与自闭谱系障碍的社会交往障碍和沟通障碍的严重程度有关.除了采用功能性磁共振成像(f MRI)对自闭谱系障碍成人的大脑皮层功能性连接进行测量外,还可以采用近红外光谱成像(f NIRS)这一较为适用于儿童和临床群体的技术,对自闭谱系障碍儿童的大脑皮层功能性连接进行测量,近红外光谱成像技术(f NIRS)作为一种光学脑成像技术,能够有效且可靠地揭示自闭谱系障碍的大脑异常功能性活动.自闭谱系障碍的大脑功能性连接,不仅是对自闭谱系障碍进行早期诊断的依据,也是对自闭谱系障碍的严重程度、预后可能性进行客观分级的指标.  

Resting state brain default network in patients with motor aphasia resulting from cerebral infarction

To explore the brain default mode network （DMN） in patients with motor aphasia resulting from cere- bral infarction, we used resting state functional magnetic resonance imaging （fMRI） to investigate the possible neural mechanism. Thirteen patients with motor aphasia resulting from cerebral infarction and ten matched controls were selected in this study. All subjects were examined using resting state fMRI. We chose the posterior cingulate cortex as the region of interest and then used functional connectivity analysis to calculate the DMN functional connectivity and analyze differences in the functional connectivity between the two groups. Compared with normal controls, aphasia patient group showed a significantly decreased functional connectivity in bilateral medial frontal gyrus, superior frontal gyrus, middle frontal gyrus, middle temporal gyrus, precuneus and cuneus. The aphasia patient group showed increased functional connectivity mainly in bilateral medial frontal gyrus, middle frontal gyrus, inferior frontal gyrus, precentral gyrus, insula. The DMN in cerebral infarction motor aphasia patients showed significantly decreased functional connectivity in the resting state. The DMN most likely plays an important role in motor aphasia resulting from cerebral infarction. Furthermore, functional connectivity inthe brain regions surrounding the left and right Broca＇s areas was significantly enhanced due to compensatory mecha- nisms. This may be helpful for the recovery of language function in cerebral infarction patients with motor aphasia.  

A potential ethnic difference in the association between 5-HTTLPR polymorphisms and the brain default mode network

The serotonin-transporter-linked polymorphic region （5-HTTLPR） is associated with mood disorders. This association is thought to be due to amygdala hyper- responsiveness to negative emotional stimuli as a result of reduced frontal cortical control. In Caucasians, the short form is associated with this effect, but in Han Chinese we recently found that the long form is involved. Serotonin receptors have rich expression in default mode network （DMN） regions and the recent studies have found an association between the short form of the 5-HTTLPR and DMN functional connectivity （FC） in Caucasians. The present study has investigated whether there may also be an ethnic difference in this influence of 5-HTTLPR on the DMN. We recruited 233 young Han Chinese subjects and calculated the resting-state default-network FC. Our study found that the L carriers had decreased FC in the bilateral medial prefrontal cortex, right parahippocampal gyrus, left middle temporal gyrus, and increased FC in left precuneus （Pcu） compared to SS. The PCC-Pcu FC in L carriers was significantly negatively correlated with the depression scores. Our findings, therefore, suggest that there is also a difference between Caucasian and Han Chinese subjects in the association between the different forms of the 5-HTTLPR and DMN functional connectivity.