Analysis of mammalian brain architecture.

The mammalian brain is composed of several distinct parts which show different growth in evolution. Clark, Mitra and Wang found that the two main cortices of the brain - the cerebral (neo-) cortex and the cerebellum - show very different growth, and that whereas the ratio of neocortex volume to total brain volume increases with evolution, the cerebellum occupies a constant proportion in different species. Here I compare the surface areas of the two cortices in different species and find that these show a simple proportionality. Contrary to the conclusion drawn by Clark et al., this linear dependence of size implies that the two major cortices increase their computational capacity in parallel, suggesting a functional dependence of the one upon the other.     

Resting state brain activity and functional brain mapping

Functional brain imaging studies commonly use either resting or passive task states as their control conditions, and typically identify the activation brain region associated with a specific task by subtracting the resting from the active task conditions. Numerous studies now suggest, however, that the resting state may not reflect true mental “rest” conditions. The mental activity that occurs during “rest” might therefore greatly influence the functional neuroimaging observations that are collected through the usual subtracting analysis strategies. Exploring the ongoing mental processes that occur during resting conditions is thus of particular importance for deciphering functional brain mapping results and obtaining a more comprehensive understanding of human brain functions. In this review article, we will mainly focus on the discussion of the current research background of functional brain mapping at resting state and the physiological significance of the available neuroimaging data.     

Resting state brain activity and functional brain mapping

Functional brain imaging studies commonly use either resting or passive task states as their control conditions, and typically identify the activation brain region associated with a specific task by subtracting the resting from the active task conditions. Numerous studies now suggest, however, that the resting state may not reflect true mental "rest" conditions. The mental activity that occurs during "rest" might therefore greatly influence the functional neuroimaging observations that are collected through the usual subtracting analysis strategies. Exploring the ongoing mental processes that occur during resting conditions is thus of particular importance for deciphering functional brain mapping results and obtaining a more comprehensive understanding of human brain functions. In this review article, we will mainly focus on the discussion of the current research background of functional brain mapping at resting state and the physiological significance of the available neuroimaging data.     

Design and implementation of a cognitive engine functional architecture

Intelligence is the most important characteristic for cognitive wireless networks. A cognitive engine built on reconfigurable wireless networks is the key to implementing this characteristic. The design and implementation of a cognitive engine is important in research on the theory of initiative cognition for cognitive wireless networks. This paper first discusses research on cognitive loops, then investigates cognitive functions in the loop through the design of a universal cognitive engine functional architecture, and finally verifies the architecture on the platform of a cognitive engine prototype system.     

A functional correlate for the dihydropyridine binding site in rat brain

Calcium channels, controlling the influx of extracellular Ca2+ and hence neurotransmitter release, exist in the brain. However, drugs classed as calcium antagonists and which inhibit Ca2+ entry through voltage-activated Ca2+ channels in heart and smooth muscle, seem not to affect any aspect of neuronal function in the brain at pharmacologically relevant concentrations. Yet the dihydropyridine calcium antagonists (for example, nitrendipine) bind stereospecifically with high affinity to a recognition site on brain-cell membranes thought to represent the Ca2+ channel and consequently, the physiological relevance of these sites has been questioned. However, activation of voltage-dependent Ca2+ channels can increase cytoplasmic Ca2+ and neurotransmitter release in neuronal tissue. We show here that Bay K8644, a dihydropyridine Ca2+-channel activator, can augment K+-stimulated release of serotonin from rat frontal cortex slices and that these effects can be antagonized by low concentrations of calcium antagonists. As 3H-dihydropyridine binding to cortical membrane preparations resembles the binding in heart and smooth muscle where there are good functional correlates we conclude that the dihydropyridine binding sites in the brain represent functional Ca2+ channels that can be unmasked under certain circumstances.     

论"固有色"及"固有色彩观念"

进行色彩写生必须具有科学的光色变化观念,从客观物象当时当地的具体色彩实际出发,排除“固有色彩观念”的干扰,抛弃对“固有色”的盲目追求,以自然为师,努力表现一切被画物象极为丰富的色彩变化。     

A functional circuit underlying male sexual behaviour in the female mouse brain

In mice, pheromone detection is mediated by the vomeronasal organ and the main olfactory epithelium. Male mice that are deficient for Trpc2, an ion channel specifically expressed in VNO neurons and essential for VNO sensory transduction, are impaired in sex discrimination and male-male aggression. We report here that Trpc2-/- female mice show a reduction in female-specific behaviour, including maternal aggression and lactating behaviour. Strikingly, mutant females display unique characteristics of male sexual and courtship behaviours such as mounting, pelvic thrust, solicitation, anogenital olfactory investigation, and emission of complex ultrasonic vocalizations towards male and female conspecific mice. The same behavioural phenotype is observed after VNO surgical removal in adult animals, and is not accompanied by disruption of the oestrous cycle and sex hormone levels. These findings suggest that VNO-mediated pheromone inputs act in wild-type females to repress male behaviour and activate female behaviours. Moreover, they imply that functional neuronal circuits underlying male-specific behaviours exist in the normal female mouse brain.     

基于静息态fMRI的人脑功能网络的小世界特性

从19个健康志愿者静息态的功能磁共振成像中提取了时间序列,计算了90个脑区的功能相关性,设定阈值建立脑功能网络的无向简单图,然后计算了一些网络测度.结果显示人脑功能网络具有小世界特性;性别分层后并没有发现各网络测度在全脑水平有显著性的性别差异.     

建筑中的动

文章以建筑中的"动"为切人点,从建筑形态、空间、环境、文脉、真正的动的建筑等方面,探析建筑中的动态元素.从人的需求和外部环境的角度,结合相应的实际案例对这一新型建筑设计方向进行研究和思考.解析了动态建筑的基本精神一动态与自然;动态建筑的基本特征--多文化、多维度、复杂动态的功能空间、回归自然的梦想;剖析了动态建筑思想的...     

自主式交通系统功能架构优化密度峰值聚类算法

自主式交通系统(autonomous transportation system, ATS)是为应对主动式智慧交通发展趋势而提出的新一代交通系统。为科学合理地构建ATS功能架构,提出了一种面向多属性文本的优化密度峰值聚类算法(density peaks clustering, DPC)。该算法结合交通系统功能架构的基本特征,通过改进的词频-逆向文档频率算法与文本向量空间模型,将多属性文本转化成空间维度坐标。再利用高斯函数和决策值优化DPC算法进行聚类,并结合轮廓系数对聚类结果进行评价。为了检验算法的合理性,在ATS道路自动驾驶场景下,基于道路载运工具运行服务域、交通基础设施管理服务域和交通安全管理服务域的功能数据集进行了算例分析,依据聚类结果绘制功能架构图。架构图由自主感知-自主学习-自主决策-自主响应4层构成,验证了ATS应用场景中功能架构优化算法的可行性和合理性。算例结果表明：该算法的构建具有鲁棒性,算例轮廓系数整体均值为0.84,与原算法相比解决了聚类过程中聚类中心难以划定的问题;与原智能交通系统中的各架构设计相比,该功能架构更具有层次性和逻辑性。该优化算法能够促进新一代交通系统...     

The temporal response of the brain after eating revealed by functional MRI

After eating, the human brain senses a biochemical change and then signals satiation, but precisely when this occurs is unknown. Even for well-established physiological systems like glucose-insulin regulation, the timing of interaction between hormonal processes and neural events is inferred mostly from blood sampling. Recently, neuroimaging studies have provided in vivo information about the neuroanatomical correlates of the regulation of energy intake. Temporal orchestration of such systems, however, is crucial to the integration of neuronal and hormonal signals that control eating behaviour. The challenge of this functional magnetic resonance imaging study is to map not only where but also when the brain will respond after food ingestion. Here we use a temporal clustering analysis technique to demonstrate that eating-related neural activity peaks at two different times with distinct localization. Importantly, the differentiated responses are interacting with an internal signal, the plasma insulin. These results support the concept of temporal parcellation of brain activity, which reflects the different natures of stimuli and responses. Moreover, this study provides a neuroimaging basis for detecting dynamic processes without prior knowledge of their timing, such as the acute effects of medication and nutrition in the brain.     

静息状态下脑网络建模及功能连接特性

实验采集静息状态下功能磁共振成像数据,经预处理后结合种子相关分析方法、t-检验法以及复杂网络理论和方法构建正常人脑功能网络.针对脑网络构建中种子相关分析法存在阈值设定随意性大的问题,引入两个原则,即设定的阈值需保证网络的整体性和小世界特性,使建立的脑网络模型充分具有实际系统的特征.在建模基础上进一步研究脑网络功能连接特性,发现网络具有明显的小世界特性;并通过计算网络中心化指标推测出后扣带回、楔前叶、楔叶以及顶上小叶等是静息状态下脑功能网络的关键脑区.     

建筑学专业“建筑材料”课程教学改革研究

城市建设的高速发展需要高素质的建筑设计人员,但传统建筑学专业的教学模式无法满足新世纪人才培养的要求。针对建筑学专业的特点和原有建筑材料课程教学模式存在的主要问题,讨论了课程的重新定位及在教学目标、内容、方法等方面的改革尝试,最后评析了改革后该课程教学的应用实效。     

SIVmac感染食蟹猴、恒河猴的外周血血象观察

目的　比较SIVmac感染的食蟹猴、恒河猴外周血粒系统变化情况。方法　常规方法进行白细胞 (WBC)和白细胞分类计数 (WBC .DC)。结果　感染了SIVmac的恒河猴、食蟹猴其外周血粒系统变化与人类AIDS外周血变化相似 ,显现规律性的白细胞数量、形态变化。感染SIVmac病毒两周后 ,恒河猴、食蟹猴的白细胞总数开始下降 ,异型淋巴细胞数开始上升 ,随后白细胞总数持续回升至高峰 ,8周后白细胞总数及异型淋巴细胞数下降 ,其中三只食蟹猴先后于 8周后死于病毒血症和早期死亡 ,余 1只猴白细胞总数于 12周后仍持续下降。结论　本文中描述的现象同人类HIV AIDS的诊断标准实验检查部分中提及的基本一致。另外 ,本实验还表明恒河猴、食蟹猴对SIVmac毒株的实验感染是敏感的 ,食蟹猴对SIVmac更敏感     

解构主义建筑浅谈

自二十世纪九十年代以来,世界各地出现了一些引人注目的解构主义建筑作品。它们的数量不多,影响力却不小,直接原因就是这些作品以完全违反常规的方式和手段来处理建筑形式问题,人们的传统价值观和审美标准等产生了一定冲击。从解构主义建筑产生的思想来源来阐述解构主义建筑的建筑意象和审美价值,为大家理解解构主义建筑提供一点参考。