关键词： EXCITATORY amino acid agents   NEURONS   RESEARCH   CHEMORECEPTORS   CARDIOPULMONARY system   RESPIRATION  

摘要： The retrotrapezoid nucleus (RTN), located in the parafacial region, contains glutamatergic neurons that express the transcriptor factor Phox2b and that are suggested to be central respiratory chemoreceptors. Studies in anaesthetized animals or in vitro have suggested that RTN neurons are important in the control of breathing by influencing respiratory rate, inspiratory amplitude and active expiration. However, the contribution of these neurons to cardiorespiratory control in conscious rats is not clear. Male Holtzman rats (280-300 g, n = 6-8) with bilateral stainless-steel cannulae implanted into the RTN were used. In conscious rats, the microinjection of the ionotropic glutamatergic agonist NMDA (5 pmol in 50 nl) into the RTN increased respiratory frequency (by 42%), tidal volume (by 21%), ventilation (by 68%), peak expiratory flow (by 24%) and mean arterial pressure (MAP, increased by 16 +/- 4, versus saline, 3 +/- 2 mmHg). Bilateral inhibition of the RTN neurons with the GABA(A) agonist muscimol (100 pmol in 50 nl) reduced resting ventilation (52 +/- 34, versus saline, 250 +/- 56 ml min(-1) kg(-1) with absolute values) and attenuated the respiratory response to hypercapnia and hypoxia. Muscimol injected into the RTN slightly reduced resting MAP (decreased by 13 +/- 7, versus saline, increased by 3 +/- 2 mmHg), without changing the effects of hypercapnia or hypoxia on MAP and heart rate. The results suggest that RTN neurons activate facilitatory mechanisms important to the control of ventilation in resting, hypoxic or hypercapnic conditions in conscious rats.

关键词： INSULIN -- Research   GLUCOSE metabolism   RESEARCH   HYPERINSULINISM   BLOOD sugar   DIABETES -- Research  

摘要： The importance of hypothalamic insulin action to the regulation of hepatic glucose metabolism in the presence of a normal liver/brain insulin ratio (3:1) is unknown. Thus, we assessed the role of central insulin action in the response of the liver to normal physiologic hyperinsulinemia over 4 h. Using a pancreatic clamp, hepatic portal vein insulin delivery was increased three- or eightfold in the conscious dog. Insulin action was studied in the presence or absence of intracerebroventricularly mediated blockade of hypothalamic insulin action. Euglycemia was maintained, and glucagon was clamped at basal. Both the molecular and metabolic aspects of insulin action were assessed. Blockade of hypothalamic insulin signaling did not alter the insulin-mediated suppression of hepatic gluconeogenic gene transcription but blunted the induction of glucokinase gene transcription and completely blocked the inhibition of glycogen synthase kinase-3 beta gene transcription. Thus, central and peripheral insulin action combined to control some, but not other, hepatic enzyme programs. Nevertheless, inhibition of hypothalamic insulin action did not alter the effects of the hormone on hepatic glucose flux (production or uptake). These data indicate that brain insulin action is not a determinant of the rapid (<4 h) inhibition of hepatic glucose metabolism caused by normal physiologic hyperinsulinemia in this large animal model. Diabetes 62:74-84, 2013

关键词： Obstructive Sleep Apnea   Continuous Positive Airway Pressure   Peak Inspiratory Pressure   Mask Ventilation   Airway Patency  

摘要： Introduction: Upper airway obstruction (UAO) is a major problem in unconscious subjects, making full face mask ventilation difficult. The mechanism of UAO in unconscious subjects shares many similarities with that of obstructive sleep apnea (OSA), especially the hypotonic upper airway seen during rapid eye movement sleep. Continuous positive airway pressure (CPAP) via nasal mask is more effective at maintaining airway patency than a full face mask in patients with OSA. We hypothesized that CPAP via nasal mask and ventilation (nCPAP) would be more effective than full face mask CPAP and ventilation (FmCPAP) for unconscious subjects, and we tested our hypothesis during induction of general anesthesia for elective surgery. Methods: In total, 73 adult subjects requiring general anesthesia were randomly assigned to one of four groups: nCPAP P0, nCPAP P5, FmCPAP P0, and FmCPAP P5, where P0 and P5 represent positive end-expiratory pressure (PEEP) 0 and 5 cm H2O applied prior to induction. After apnea, ventilation was initiated with pressure control ventilation at a peak inspiratory pressure over PEEP (PIP/PEEP) of 20/0, then 20/5, and finally 20/10 cm H2O, each applied for 1 min. At each pressure setting, expired tidal volume (Vte) was calculated by using a plethysmograph device. Results: The rate of effective tidal volume (Vte > estimated anatomical dead space) was higher (87.9% vs. 21.9%;P<0.01) and the median Vte was larger (6.9 vs. 0 mL/kg;P<0.01) with nCPAP than with FmCPAP. Application of CPAP prior to induction of general anesthesia did not affect Vte in either approach (nCPAP pre-vs. post-;7.9 vs. 5.8 mL/kg, P = 0.07) (FmCPAP pre-vs. post-;0 vs. 0 mL/kg, P = 0.11). Conclusions: nCPAP produced more effective tidal volume than FmCPAP in unconscious subjects.

关键词： 沾益县   惠泽   疾病预防控制中心   彰显   意识  

摘要： 沾益县疾病预防控制中心成立于2003年,前身为沾益县卫生防疫站和沾益县健康教育所。现有业务用房2800m2,职工31人,内设疾控科、免规科、艾防科、慢传科、慢病科、公卫科、健教科、检验科、预防接种门诊、办公室。2004年9月获得全国碘缺乏病实验室质量控制网络合格实验室资质;2004年12月中心实验室通过国家计量认证;2005年9月获得职业健康检查资质;2006年9月获得艾滋病初筛实验室资质;建立了传染病、地方病、职业病、艾滋病、结核病、免疫

关键词： 太极拳   运动   意识控制   神经系统   反馈信息   大脑皮层   循环   休养   思想   祛病   气相   能力   导体   丹田   病灶  

摘要： 练太极拳的要求心静用意,以意导体,用意识来支配动作,使思想高度入静,从而提高自我意识控制神经系统的能力.太极拳运动强调缓慢自然,意、气相合,排除一切杂念,意守丹田,在大脑皮层产生祛病强身良性反馈信息的传递,能修复病灶,纠正恶性循环,抑制病情发展,有利于病体的恢复和休养.

关键词： 高中生   实验条件   定量控制  

摘要： 化学实验是化学科学赖以产生和发展的基础，随着教育改革的实施和深入，化学课程也发生了巨大的变化，从而使人们对化学实验教学有了新的认识和评价。在化学实验教学中，实验条件的控制十分重要，同一实验控制的条件不同，或者同一条件控制的程度不同，反应的过程或产物就可能不同，如：反应物的浓度、纯度，外界条件如温度，试剂方面如状态、用量、顺序等等。学生对化学实验中变量的控制及实验条件的定量分析能力在化学实验教学中非常重要，就这一问题，我以高二年级的学生为研究对象，通过文献分析法、调查问卷法、统计分析法，参考荷兰数学教育家希勒的几何学五级思维水平理论，对调查问卷的结果进行统计分析后，尝试对定量控制进行五级理解水平的制定及划分，并对其影响学生定量控制认识理解水平的原因进行解读分析。

关键词： Definition of Life   Model of Mind   Consciousness   Cybernetics   Self-Reference   System Complexity  

摘要： The previously proposed cybernetic definition of a living (biological) individual and the cybernetic model of a psychical individual (a self endowed with subjective consciousness) are extended and compared, and their formal similarities are isolated and highlighted. It is argued that the emergence of the biological level of reality from the physical level and of the psychical level from the biological level is closely analogous. The (biological or psychical) individual is constituted by a network of elements (negative feedbacks/ regulatory mechanisms or neurons/concepts, respectively) that possesses the following common proper ties: 1) it is intentional (in the operational sense); 2) its elements signify (have sense) by connotation (through relations to each other); 3) it contains an instrumental representation of (some aspects of) the world and 4) it is self-referential i. e. recurrently directed on itself (its own reproduction or representation, respectively). Thus life and self-consciousness have deep, formal, structural similarities when viewed ab stractly. The cybernetic definition/model of an individual is also referred to societies/states, companies and other systems. It is postulated that this definition/model is a universal one and can be applied to all possible systems/objects existing in the Universe or constructed in the future by humans.

关键词： 脑电信号   K近邻互信息   双树复小波变换   分数阶傅里叶变换   粒子群优化   支持向量机  

摘要： 脑电（Electroencephalogram，EEG）是一种脑神经细胞的生物电活动，反映了大脑的功能状态，有效提取脑电信号中蕴含的信息，对于临床医学、康复工程、脑机接口等诸多领域的研究有着重要的意义。要使脑电信号控制的康复辅助装置能够按照使用者意愿智能化地服务于患者，如何有效提高不同场景下运动想象的识别率是其中的瓶颈和难点之一，并且已成为康复工程领域中具有挑战性的科学问题。 本文在国家自然科学基金项目（61172134）的支持下，从课题研究的背景及意义出发，结合脑电信号的特点，研究分析了运动想象状态下脑电信号的采集与预处理、特征提取及模式分类等过程，探讨了基于多类意识任务识别的电动轮椅脑电控制方法。本文主要完成了以下研究工作，并取得了部分创新成果： （1）在脑电信号预处理阶段：提出了一种基于最小相依成分分析的互信息（Mutual Information based on Least dependent Component Analysis，MILCA）算法的脑电信号伪迹消除方法。针对脑电信号中眼电和心电串扰伪迹，首先用提升小波硬阈值法对多路原始脑电信号去噪，再运用MILCA算法对各通道信号进行盲源分离，同时采用信号间互相关系数和互信息量作为指标对伪迹分离的效果进行评价。实验对比分析表明，运用MILCA算法能较好地去除脑电信号中的眼电及心电伪迹，为后续的特征提取创造了良好的条件。 （2）在脑电信号特征提取阶段：针对离散小波变换处理信号时存在的频谱混叠现象和平移不变性差的问题，探讨了实虚二元树滤波器形式双树复小波变换的原理以及特点，在此基础上提出了基于双树复小波变换能谱熵的脑电信号特征提取方法。此外，还研究了通过改变单一变量阶次p来自动调节时频局部特性的离散分数阶傅里叶变换，结合K近邻互信息估计与熵理论，提出了基于离散分数阶傅里叶变换互信息熵的脑电信号特征提取方法。 （3）在脑电信号模式分类阶段：提出了基于粒子群算法优化支持向量机的脑电信号模式分类方法，解决了与分类性能相关的最优参数（惩罚因子C、核函数中的参数变量）选取问题，与传统网格划分搜索最优参数的方式相比，算法效率明显提高。 （4）研究了离线状态下脑电控制电动轮椅的稳健方法，给出了基于脑电信号控制电动轮椅实验平台的总体方案，以及基于单片机的电动轮椅控制器改造等，设计了脑电信号采集的实验方案，对应轮椅前进、停止、左转和右转四种控制方式，研究了右脚踩油门、左手握轮椅控制杆向后移、左脚单脚跳并双手推轮椅向左移和右手握轮椅控制杆向上移四种动作作为运动想象的模式。实验结果表明，对于C3、Cz和C4三个通道的脑电信号，选取基于双树复小波变换能谱熵及频带复系数能量的15维特征和基于离散分数阶傅里叶变换互信息熵的72维特征组成的的联合特征向量，经过归一化和PCA降维处理后，采用粒子群算法优化支持向量机分类器进行分类，对于3类和4类纯运动场景的想象识别，平均分类正确率分别达到了75.57%和69.68%，其分类结果验证了本文所提出的基于脑电信号特征提取和模式识别算法的有效性。

关键词： 纪录片创作   真实性   现场控制  

摘要： 从世界上第一部纪录片诞生以来,纪录片的创作者和学者们开创了无数个创作流派和理论思潮。从弗拉哈迪“对现实的创造性处理”的纪录片拍摄手法到怀斯曼的“直接电影”理论乃至后来的新纪录电影,创作者们在坚持纪录片表现真实的基础上展开讨论,讨论的焦点就在于创作者在拍摄过程中的主观控制和艺术创造对客观现实的改造程度。 历史的实践证明,哲学意义上的绝对真实在电影中是不存在的。纪录片所传达的真实依赖于创作者对真实的态度和对现场拍摄影像语言的掌握技巧。纪录片需要将镜头前的真实现场经过创作者的主观意识改造并通过视听语言转译为给观众看到的现场真实。这个转译的过程就是纪录片拍摄的控制过程。 纪录片拍摄的现场控制,是纪录片创作者面对拍摄现场的复杂环境,经过分析并对拍摄对象的现场状态进行判断和把握,通过一定的视听语言有选择有控制地进行拍摄工作。由于纪录片的纪实本性,拍摄内容往往是原生态的生活场景,所以要求纪录片导演需要用现场的分镜头意识来控制拍摄团队与被拍对象进行现场调度,要求摄影师通过对视听语言的运用在现场选择不同的拍摄方案,并且能够在后期剪辑的呈现上尽可能真实的传达现场情感,最终形成一定的艺术风格,塑造优秀的艺术形象,在整体上提高纪录片的艺术水准。

关键词： 成本控制   工程造价   经济效益  

摘要： 工程造价管理是工程建设中重要的组成部分,加强工程造价管理,做好成本控制,是促进企业发展的重要因素之一。对建筑施工企业进行造价管理主要目标是为了能够合理控制造价成本,用最低的成本做出最大效益,促进整体效益最大化。每一个施工企业都具有不同的状况,需要在施工的实践中进行方法总结,创造出能够促进自身发展的成本控制方案。本文对工程造价管理以及成本控制进行研究,希望通过一系列研究,能够促进施工企业经济效益提高。