Optical Tissue Clearing to Study the Intra-Pulmonary Biodistribution of Intravenously Delivered Mesenchymal Stromal Cells and Their Interactions with Host Lung Cells

Mesenchymal stromal cells (MSCs) injected intravenously are trapped in the capillaries of the lungs and die within the first 24 h. Studying the biodistribution and fate of labelled therapeutic cells in the 3D pulmonary context is important to understand their function in this organ and gain insights into their mechanisms of action. Optical tissue clearing enables volumetric cell tracking at single-cell resolution. Thus, we compared three optical tissue-clearing protocols (Clear, Unobstructed Brain/Body Imaging Cocktails and Computational analysis (CUBIC), modified stabilised 3D imaging of solvent-cleared organs (s-DISCO) and ethyl cinnamate (ECi)) to evaluate their potential to track the biodistribution of human umbilical cord MSCs expressing the tdTomato fluorescence reporter and investigate how they interact with host cells in the mouse lung. The results showed that although CUBIC clearing is the only method that enables direct imaging of fluorescently labelled MSCs, combining s-DISCO or ECi with immunofluorescence or dye labelling allows the interaction of MSCs with endothelial and immune cells to be studied. Overall, this comparative study offers guidance on selecting an optical tissue-clearing method for cell tracking applications.     

基于复合动态模型和证据融合架构的移动物体检测与跟踪方法

针对现有方法中移动物体检测与跟踪的准确性精度较低的缺点,提出一种基于多传感器检测分类的移动物体描述和感知方法：建立了一个包含核心对象动态特征和分类描述的复合模型,在此基础上设计了一个基于证据框架的信息感知与融合方法,通过整合动态模型和不确定性特征来实现对移动物体的检测和跟踪。为了验证所提方法的有效性,在一辆安装有雷达、激光雷达和摄像头的演示车上进行了相关实验,在不同驾驶场景下针对行人、卡车和轿车三个移动物体进行了检测与跟踪,实验结果证明所提方法具有非常高的准确性。     

Give us today our daily bread: The effect of hunger on consumers’ visual attention towards bread and the role of time orientation

This study investigated the effect of hunger on consumers’ visual attention during a food choice task, and the role of time orientation (i.e., present and future orientation) in this interplay. A lab-based eye-tracking experiment including 102 participants was conducted, with hunger as the manipulated factor (hungry, satiated). Participants in the satiated condition were served a breakfast buffet before the experimental tasks, whereas participants in the hungry condition were served the buffet after completion of the tasks. Both groups were exposed to a set of planograms depicting supermarket shelves and were asked to choose an option they could consider buying, while their eye movements were recorded. Stimuli included non-food items as well as the key category of interest, Swedish crisp bread. After completion of the eye-tracking recordings, participants indicated their time orientation as well as their height and weight, which were used to calculate body mass index (BMI). The results revealed that hunger (vs. satiation) increased participants’ present orientation and visual attention towards bread, but decreased their future orientation, with participants’ present orientation mediating the effect of hunger on visual attention. Additional exploratory analyses revealed a positive correlation between participants’ BMI and their present orientation. Taken together, the results offer several fruitful avenues for future research, which may be used to promote public health. Moreover, the findings contribute to the literature by documenting that hungry individuals do not necessarily make more rapid decisions in drive-relevant domains; rather, they may actually devote a larger share of their attentional resources in the food domain, given their desire to acquire food.     

Large error recovery for a class of frequency tracking algorithms

The performance of a recently proposed high-order adaptive notch filter (HANF) for frequency estimation and tracking is studied. An analysis technique utilizing approximations with linear filters is employed to derive closed-form performance expressions for a noisy sinusoidal input signal. Important performance measures, such as stability, noise rejection, statistical efficiency, and tracking ability, are studied in detail, and rules for the design variables are given. A study is presented where the performance of HANF is compared with the performance of a minimal order adaptive notch filter (ANF), as well as with a frequency tracker based on least squares-modelling—the multiple frequency tracker (MFT). The study reveals that HANF is a competitive alternative to ANF, but also that, in general, the MFT is the method of choice. © 1998 John Wiley & Sons, Ltd.     

天然光光环境模拟软件的对比研究

合理利用天然光,不仅可以改善室内的光环境,同时也有利于照明节能。为了实现良好的光环境,设计师需要在设计阶段准确把握光环境的效果、照明系统的性能和运行情况,从而进行合理的设计。随着计算机技术的发展,光环境模拟软件因其成本低、周期短和准确性高日益受到人们的重视,并在包括设计、建造、维护和管理等各阶段的建筑全寿命周期内得到了广泛应用。本文对目前常用的天然光光环境模拟软件进行了分类和简要介绍,并选择WINDOW、Sunshine、Radiance、Ecotect、Daysim等软件进行了比较分析,以便于使用者针对不同的应用进行选择和应用。     

球坐标法激光跟踪测量系统自校正方法研究

建立了测量系统运动学模型;针对以往球坐标激光跟踪系统中参考点只能借助于外部具有更高精度的仪器来校正的缺点,提出平面约束自校正方法,并对测量系统进行了自校正研究。仿真结果表明了平面约束自校正方法的有效性。     

电动汽车集群内的递阶分散最优充电方法

电动汽车未来有望以集群（例如大型充电站内的电动汽车）形式参与电网调度。收到电网下发的集群优化充电调度指令后,集群代理需优化集群内的电动汽车充电功率以追踪电网指令。该追踪问题是一个大规模的优化问题,难于集中式求解。提出一种递阶分散优化算法求解该问题。集群代理下发协调信息,各电动汽车根据协调信息分布式地优化自身充电功率,并向代理返回迭代信息,通过迭代求得问题的最优解。为进一步提高计算效率,对集群代理和单辆汽车的优化子问题进行了深入研究和算法改进。通过数值实验发现所提方法具有很快的计算速度,尤其适用于求解大规模电动汽车集群内的追踪问题。     

负载适应型光伏模块集成式变换器设计

此处研究了负载适应型模块集成式变换器(MIC)的有限状态机及最大功率点跟踪(MPPT)算法。利用状态空间平均法求解变换器在输出电压控制模式下的传递函数并设计了控制器:分析了MIC在不同运行工况下控制变量的特征,并以此为依据设计了系统的有限状态机,实现了控制回路层面上状态快速切换;为有效解决光伏MPPT快速性与最大功率点稳态振荡的问题,光伏MPPT采用变步长电阻增量法。系统采用dsPIC33FJ06GS606数字信号控制器实现底层闭环控制的有限状态机与MPPT算法,并通过样机实验验证了系统设计的可行性。     

光伏并网发电及无功补偿的统一控制

针对常规光伏并网发电系统逆变主电路的结构特点,提出了将无功功率补偿与光伏并网发电相结合的新型控制方案,使光伏并网发电系统在向电网提供有功电能的同时也能够提供电网所需的无功电能,从而简化系统结构,提高供电能力,并节省设备投资.文中详细分析了系统控制结构、瞬时无功检测、并网电流的合成及并网电流的跟踪控制方法.系统以DSP数字信号处理器为基础,在30kVA光伏并网功率调节器实验样机中成功地实现了光伏并网发电和无功功率补偿的统一控制.