摘要：Organ-on-a-chip systems have been increasingly recognized as attractive platforms to assess toxicity and to develop new therapeutic ***,current organ-on-a-chip platforms are limited by a“single pot”design,which inevitably requires holistic analysis and limits parallel ***,we developed a digital organ-on-a-chip by combining a microwell array with cellular microspheres,which significantly increased the parallelism over traditional organ-on-a-chip for drug *** to 127 uniform liver cancer microspheres in this digital organ-on-a-chip format served as individual analytical units,allowing for analysis with high consistency and quick *** platform displayed evident anti-cancer efficacy at a concentration of 10μM for sorafenib,and had greater alignment than the“single pot”organ-on-a-chip with a previous in vivo *** addition,this digital organ-on-a-chip demonstrated the treatment efficacy of natural killer cell-derived extracellular vesicles for liver cancer at 50μg/*** successful development of this digital organ-on-a-chip platform provides high-parallelism and a low-variability analytical tool for toxicity assessment and the exploration of new anticancer modalities,thereby accelerating the joint endeavor to combat cancer.

摘要：This paper discusses the model-based predictive controller design of networked nonlinear systems with communica- tion delay and data loss. Based on the analysis of the closed-loop networked predictive control systems, the model-based networked predictive control strategy can compensate for communication delay and data loss in an active way. The designed model-based predictive controller can also guarantee the stability of the closed-loop networked system. The simulation re- suits demonstrate the feasibility and efficacy of the proposed model-based predictive controller design scheme.

摘要：A deterministic approach is frequently used in engineering design. In this quantitative design methodology, a safety factor, which is typically a strength-to-stress ratio, is derived as an index for the stability assessment of the engineering design. In underground coal mining applications such as pillar design,however, the inputs of pillar design are variables. This is widely overlooked in the deterministic approach. A probabilistic approach assessing the probability of failure or reliability of a system might be an alternative to the conventional quantitative methodology. This approach can incorporate the degree of uncertainty and deviations of variables and provide more versatile and reliable results. In this research, the reliability of case histories from stable and failed pillars of South Africa presented by Merwe and Mathey is examed. The updated Salamon and Munro strength formula(S-M formula) and Merwe and Mathey strength formula(M-M formula) are evaluated through a probabilistic approach. It is concluded that stable pillar cases have a reliability value greater than 0.83 while the reliability value of failed pillar cases are slightly larger than 0.50. There seems to be a positive relation between safety factor and reliability. The reliability of a pillar increases with pillar width but decreases with depth of cover, pillar height and entry width. The reliability analysis also confirms that M-M strength formula has a better distinction between the stable and failed pillar cases.

摘要：磁流变(MR)材料是一类智能材料,通常为流体、胶泥或弹性体状,其特性可以利用磁场进行控制。在本研究中,利用硅橡胶基体与羰基铁粉填充颗粒制备各向同性与各向异性磁流变弹性体,为研究磁流变弹性体的磁致电感特性设计了试验电感器。采用自建的可产生恒定与瞬态激励磁场的试验系统表征磁流变弹性体的填充颗粒含量、制备条件等因素对磁致电感特性的影响。研究结果表明:上述影响因素对磁流变弹性体电感器在外加磁场下的电感特性有明显影响,各向同性磁流变弹性体电感器的电感变化比各向异性磁流变弹性体电感器的更为显著。此外,在恒定磁场作用下,磁流变弹性体电感器的电感值随着外加磁场激励的增强而衰减,并深入分析了磁致影响机理。本研究成果可以促进磁流变弹性体用于检测外磁场或磁流变材料内部填充颗粒含量。

摘要：鞭毛和纤毛独特的运动模式(如鞭毛的平面/螺旋波形式推进和纤毛的二维/三维不对称搏动)在众多生物的生命活动中起到至关重要的作用,这也启发了诸多仿生设计,尤其对于微型机器人系统。然而,与自然界中微生物能够从统一化的9+2轴丝生物结构中进化出多种运动模式不同的是,当前的仿生学仍然没有有效的工程策略去实现这样的智慧。在此,我们通过研究鞭毛和纤毛的内部结构及其内在驱动机制,推导出了一个统一的物理模型来描述微管弯曲及其所构建的宏观鞭毛/纤毛运动。基于该模型,我们进而提出了基于三通道的管状驱动概念,并相应地通过杆嵌入铸造工艺制造了一个三通道的管状驱动器。通过编程不同通道的驱动模式,这一管状驱动器不仅可以再现自然界中多样的二维及三维鞭毛/纤毛运动,还可以延展出更多的非对称纤毛搏动模式以实现低雷诺数下的有效推进。该研究加深了我们对微生物推进机制的理解,为仿生系统的设计提供了新灵感,并有望在广泛的工程领域中寻找到重要的应用场景。

摘要：The ability to finely control the structure of protein folds is an important prerequisite to functional protein design. The TIM barrelfold is an important target for these efforts as it is highly enriched for diverse functions in nature. Although a TIM barrel proteinhas been designed de novo, the ability to finely alter the curvature of the central beta barrel and the overall architecture of the foldremains elusive, limiting its utility for functional design. Here, we report the de novo design of a TIM barrel with ovoid (twofold)symmetry, drawing inspiration from natural beta and TIM barrels with ovoid curvature. We use an autoregressive backbonesampling strategy to implement our hypothesis for elongated barrel curvature, followed by an iterative enrichment sequencedesign protocol to obtain sequences which yield a high proportion of successfully folding designs. Designed sequences arehighly stable and fold to the designed barrel curvature as determined by a 2.1Å resolution crystal structure. The designs showrobustness to drastic mutations, retaining high melting temperatures even when multiple charged residues are buried in thehydrophobic core or when the hydrophobic core is ablated to alanine. As a scaffold with a greater capacity for hosting diversehydrogen bonding networks and installation of binding pockets or active sites, the ovoid TIM barrel represents a major steptowards the de novo design of functional TIM barrels.

摘要：经由在空中的位置和取向系统(POS ) 获得的数据在 WGS 84 全球以地球为中心的引用框架，当为在中国的地志的印射的国家并列引用系统通常是 Gauss-Kruger 设计坐标系统时。因此，经由 POS 获得的数据必须被转变到国家坐标系统。由于地球弯曲和顶点偏差的效果，在从转动，沥青，和标题的角度转变的过程有一些错误(桅，螛，经由 POS 直接获得到图象的态度角度的唯)( 蠁，蠅，在摄影测量学需要的魏) 。根据外面的取向上的地球弯曲和顶点偏差的效果理论图象的尖元素，使用一个赔偿矩阵从态度角度改正转变错误的一个方法经由 POS 获得了到外面的取向图象的尖元素在这份报纸被建议。而且，赔偿矩阵的严密公式被推出。经由 POS AV 510 获得的实际数据的二个集合，在规模和地面不同，被选择并且过去常执行实验。实验结果不仅显示赔偿矩阵在这建议纸正确、实际而且证明尖元素基于赔偿矩阵经由 POS 获得了的外面的取向的那转变精确性与 Gauss-Kruger 设计的垂直的轴(中央顶点的设计)的选择相关坐标系统；合适的垂直的轴应该是调查区域在定位的设计地区的中央顶点的 Gauss-Kruger 设计。然而，外面的取向的转变精确性尖元素与坐标系统的起源的选择无关；坐标系统的起源在调查区域的中心点定位，是适当的。而且，尖元素基于在这份报纸推出的赔偿矩阵完成了的外面的取向的转变精确性比经由处理软件的存在 POS 获得了的高。

摘要：目的职业认同在护士的长远发展中起着重要作用,当发生突发公共卫生事件时,职业认同情况会发生变化。本研究旨在探讨新型冠状病毒疫情期间护理专业本科生职业认同情况及相关因素。方法采用横断面调查研究设计,通过便利抽样方法,于2020年3—4月对7所院校的3,875名护理专业本科生进行调查。采用一般资料问卷收集基本信息,采用护生职业认同问卷调查新型冠状病毒疫情早期和后期护理专业本科生的职业认同情况。结果疫情后期护理专业本科生的职业认同得分(59.49±12.41)明显高于早期(56.96土12.61)。逐步回归分析结果显示,学生的性别、居住地、专业(康复护理)、疫情对毕业后工作意愿的影响、选择护理专业的原因及疫情早期职业认同得分与疫情后期的职业认同水平有关联。结论护理教育工作者可以利用应对突发公共卫生事件的积极影响,提高学生的职业认同。同时,在突发公共卫生事件发生后,教育工作者应对职业认同较低的学生进行更有针对性的教育,培养其职业认同感。

摘要：拓宽材料对光子的吸收是利用太阳光能的关键.然而,要平衡电极材料对光的最大化吸收与存储是当前光电极材料的设计难点.本文报道了一种具有丰富硫空位的Cu_(2)S/CuCl异质阵列材料,该材料中CuCl与硫空位的存在增加了其对光子的捕获与转化.同时,Cu_(2)S/CuCl异质结增加了材料的导电性能,促进了电子的传输效率.当作为赝电容的电极材料时,该Cu_(2)S/CuCl双功能材料的光照下容量提升比率高达35%.同时,由该材料制成的非对称电容器循环测试6000次之后的面积比容量可依旧维持在670 mF cm^(-2).该Cu_(2)S/CuCl材料具有优异的光电化学性能,在下一代光辅助充电储能器件的应用领域展示出巨大前景.

摘要：Liver injury is a common cause of drug approval withdrawal during drug development,pre-clinical research,and clinical *** not properly treated,patients with severe liver injury can suffer from acute liver failure or even ***,utilization of the convenient in vitro hepatotoxicity assessment model for early detection of drug-induced hepatotoxicity is vital for drug development and safe personalized ***(e.g.,hydrogels,nanofibers,decellularized liver matrix)and bioengineering technologies(e.g.,microarrays,micropatterns,3D printing,and microfluidics)have been applied for in vitro hepatotoxicity assessment *** review summarizes the structure and functions of the liver as well as the components of in vitro hepatotoxicity assessment *** addition,it highlights the latest advances in developing hepatotoxicity models with the ultimate goal of further clinical translation.