脑肌电多设备集成系统的接口硬件设计

脑肌电控制是使用人的脑电和肌电信号对设备进行控制的新型人机控制方式。为了方便其多设备类型集成控制系统的构建,设计了一种兼容多设备控制信号的新型脑肌电控制系统信号接口,详细描述了其3层结构工作原理、不同模式的工作流程以及各功能模块的硬件设计。接口还具备针对误操作的安全保护功能,该功能采用显示反馈和二次确认的方式实现,可以有效优化控制系统的安全性能。     

Activated human eosinophils generate SRS-A leukotrienes following IgG-dependent stimulation

Eosinophils, a class of granular leukocytes, are prominent in many inflammatory processes, particularly in asthma, certain allergic diseases and during infections with helminthic parasites. Following incubation with the Ca ionophore A23187 (refs 1-4) (a non-physiological agent which circumvents membrane calcium-gating mechanisms), eosinophils generate large amounts of sulphidopeptide leukotrienes, potent inducers of smooth muscle constriction and mucus production. These are now known to represent the activity previously termed 'slow-reacting substance of anaphylaxis' (SRS-A) but attempts to identify a physiological stimulus for SRS-A production by eosinophils have so far been unsuccessful. The cells contain recognized receptors for IgG (Fc) and it is known that they adhere to, and can be activated by, contact with the surface of large organisms such as helminthic larvae. We show here that eosinophils, particularly when activated, produce sulphidopeptide leukotrienes after contact with large particles coated with IgG.     

电子转移法配平氧化还原反应方程式

<正> 在无机化学教材中,氧化还原反应方程式的配平介绍了两种方法:氧化数法和离子—电子法。这两种方法美中不足之处是配平过程较为烦琐,我在教学实践中摸索出用电子转移法配平氧化还原反应方程式,过程较为简便,今介绍于下: 方法要点:1.书写基本反应式。2.把一分子(1离子)氧化剂得电子数目写在还原剂分子式前面。3.把一分子还原剂失电子数目写在氧化剂分子式前面。4.配平其它物质系数。     

机器人多指手抓取动态稳定性分析

指出动态稳定性是评价机器人多指手执行抓取操作的一项重要指标,避免构造Lyapunov函数而给出了机器人多指手抓取稳定性研究的一种新方法,得到了抓取系统指数稳定的充分条件。     

利用加权范数估计机器人抓取系统的吸引域

为了研究多指手机器人抓取系统的动态稳定性，引入了矩阵的加权范数；继而应用抓取矩阵的加权范数及其测度，得出抓取系统的渐近稳定、不稳定的条件，以及渐近稳定时系统平衡点的吸引域估计；最后得到抓取系统弹性矩阵以及减震矩阵正定时，方使抓取系统渐近稳定。     

Induction of c-fos-like protein in spinal cord neurons following sensory stimulation

It has been suggested that the proto-oncogenes c-fos and c-myc participate in the control of genetic events which lead to the establishment of prolonged functional changes in neurons. Expression of c-fos and c-myc are among the earliest genetic events induced in cultured fibroblast and phaeochromocytoma cell lines by various stimuli including growth factors, peptides and the intracellular second messengers diacylglycerol, cAMP and Ca2+. We report here that physiological stimulation of rat primary sensory neurons causes the expression of c-fos-protein-like immunoreactivity in nuclei of postsynaptic neurons of the dorsal horn of the spinal cord. Activation of small-diameter cutaneous sensory afferents by noxious heat or chemical stimuli results in the rapid appearance of c-fos-protein-like immunoreactivity in the superficial layers of the dorsal horn. However, activation of low-threshold cutaneous afferents results in fewer labelled cells with a different laminar distribution. No c-fos induction was seen in the dorsal root ganglia, gracile nucleus or ventral horn. Thus, synaptic transmission may induce rapid changes in gene expression in certain postsynaptic neurons.     

Hormonal stimulation of adenylyl cyclase through Gi-protein beta gamma subunits.

Agonist-bound receptors activate heterotrimeric (alpha beta gamma) G proteins by catalysing replacement by GTP of GDP bound to the alpha subunit, resulting in dissociation of alpha-GTP from the beta gamma subunits. In most cases, alpha-GTP carries the signal to effectors, as in hormonal stimulation and inhibition of adenylyl cyclase by alpha s and alpha i respectively. By contrast, genetic evidence in yeast and studies in mammalian cells suggest that beta gamma subunits of G proteins may also regulate effector pathways. Indeed, of the four recombinant mammalian adenylyl cyclases available for study, two, adenylyl cyclases II and IV, are stimulated by beta gamma. This effect of beta gamma requires costimulation by alpha s-GTP. This conditional pattern of effector responsiveness led to the prediction that receptors coupled to many G proteins will mediate elevation of cellular cyclic AMP, provided that Gs is also active. We now confirm this prediction. Coexpression of mutationally active alpha s with adenylyl cyclase II converted agonists that act through 'inhibitory' receptors (coupled to Gi) into stimulators of cAMP synthesis. Experiments using pertussis toxin and a putative scavenger of beta gamma, the alpha subunit of transducin, suggest that beta gamma subunits of the Gi proteins mediated this stimulation. These findings assign a new signalling function to beta gamma subunits of Gi proteins, the conditional stimulation of cAMP synthesis by adenylyl cyclase II.     

非负线性组合多指抓取动态力优化方法

为了提高多指抓取动态力优化方法的快速性,提出了一种非负线性组合求初值,结合半正定规划(SDP)算法进行动态力优化的方法。该方法根据抓取力集为凸锥的特性,首先将外力旋量分解为12个单位力向量的线性组合,然后离线计算各单位力向量对应的初始基可行解,通过线性组合得到抓取力优化问题的初值,在此基础上调用SDP算法进行动态抓取力优化。以有摩擦点接触三指抓取长方体的仿真为例,该初值算法仅需100步迭代即可收敛,耗时0.471 ms,且初值与最优值的偏差小,在线计算量小。该方法可以用于多指机械手的抓取控制与仿真,能够实现对连续变化外力旋量的抓取力优化。     

基于恢复动力学生态系统恢复建设的研究

针对退化、半退化生态系统的恢复建设,创新性地建立了物群植物恢复模型,在生态恢复动力学的基础上,分析了物群与环境、植入物群与原有物种之间的关系,运用MATLAB进行求解,研究得出:在人工植入时,要选择蒸发系数小于固水系数的草本和灌木作为物群植入对象而非蒸发系数很大的乔木,要选择物种相近的植物作为植入对象,这样可提高生态系统物种丰富度。     

论禅宗宗旨对宗教掌握论的超越

马克思在《〈政治经济学批判〉导言》中 ,提出了理论的、艺术的、宗教和实践 -精神四种人类掌握世界的方式。宗教掌握世界的方式是一种对世界颠倒的反映 ,是人脑中脱离现实的幻想。而禅宗的宗旨 :“不立文字、教外别传、直指人心、见性成佛。”却超越了宗教掌握论     

河道生态修复工程的组成与生态修复指导原则

阐述了河道生态修复工程的组成,包括计划编制、计划实施、效果评估、适应管理和成果宣传等5个相互联系的组成部分,并参考美国环保局总结的生态修复经验,比较详细地论述了包括河道在内的生态修复的指导原则。     

恢复生态学在隔河岩库区消落带生态修复中的应用

本文针对库区消落带的特点和生态恢复的目标,以恢复生态学的相关基本理论知识为指导,对隔河岩库区消落带进行了生态恢复,实践结果表明示范地的生态恢复模式能够恢复隔河岩库区消落带的生态功能、保护生物多样性及改善库区生态环境,为日后三峡库区其他相关消落带的生态治理提供一定的参考.