Eulerian Algorithms for Computing the Forward Finite Time Lyapunov Exponent Without Finite Difference upon the Flow Map

In this paper, effective Eulerian algorithms are introduced for the computation of the forward finite time Lyapunov exponent (FTLE) of smooth flow fields. The advantages of the proposed algorithms mainly manifest in two aspects. First, previous Eulerian approaches for computing the FTLE field are improved so that the Jacobian of the flow map can be obtained by directly solving a corresponding system of partial differential equations, rather than by implementing certain finite difference upon the flow map, which can significantly improve the accuracy of the numerical solution especially near the FTLE ridges. Second, in the proposed algorithms, all computations are done on the fly, that is, all required partial differential equations are solved forward in time, which is practically more natural. The new algorithms still maintain the optimal computational complexity as well as the second order accuracy. Numerical examples demonstrate the effectiveness of the proposed algorithms.     

中药产业应对“一带一路”倡议的知识图谱分析

目的:分析"一带一路"倡议和中药产业的研究热点,为中药产业发展提供全新、系统的参考数据。方法:在中国知网以主题词的形式进行专业检索,使用CiteSpace软件绘制关键词网络图谱、聚类图谱、叠加图谱。结果:"一带一路"倡议研究现状以所涉及的区域经济、文化、社会协同发展等为主;中药产业研究现状以中药资源与种植、中药产业链、中药现代化、人才培养、中药产品研发和保护等为主;中药产业应对"一带一路"倡议的出路在于相关的政府机构对中药产业的政策支持、人才培养、中药产业相关的企业和个人要重视中药国际化和持续化发展、竞争力的培养等。结论:中药产业的良好、健康发展,需要党和各级政府适时出台各种有利于促进中药产业发展的政策和措施,社会各界要为中药产业的发展培养需要的人才、提供建议,中药企业要善于利用SWOT分析技术,坚持特色,重点培养核心竞争力。     

Roles for Event Representations in Sensorimotor Experience,Memory Formation,and Language Processing

The unifying theme for the papers in this volume is that event‐predictive representations play an important role in cognitive processes, and they are a particularly fruitful object of study for cognitive scientists. In this paper, we present our own model of event representations that draws together several disparate strands of research into event representations, relating to event perception, event encodings in working memory and their role in prediction, and events as they are reported in language. Our main claim is that the notion of deictic routines originally developed by Ballard et al. (1997) is of great use in explaining how these different types of event representation interface with one another.     

基于CiteSpace的中药溯源研究热点可视化分析＊

目的 归纳梳理中药溯源领域的研究现状和热点，分析发展趋势。方法 检索知网，万方，维普等中文文献数据库中2003年-2020年7月与中药溯源相关的文献并进行整理和归纳。使用CiteSpace 5.5 R2进行文献关键词，作者，机构的共现分析，获取对应知识图谱。结果 整理后共收集到196篇文献，通过分析，有三个团队在中药溯源领域内有稳定合作关系；机构之间合作较少且存在地域性，研究成果存在断档；热点关键词为质量追溯，物联网，区块链，二维码等。结论 中药溯源领域现处于稳定起步阶段，发文数量逐年趋于稳定，中药溯源系统与区块链，物联网，DNA条形码技术的融合，质量追溯体系的构建是相关研究的热点。NB-IoT，EPC编码等物联网技术在中药溯源系统中的运用未来将会受到更多学者关注。     

Episodic memory: Neuronal codes for what,where, and when

Episodic memory is defined as the ability to recall events in a spatiotemporal context. Formation of such memories is critically dependent on the hippocampal formation and its inputs from the entorhinal cortex. To be able to support the formation of episodic memories, entorhinal cortex and hippocampal formation should contain a neuronal code that follows several requirements. First, the code should include information about position of the agent (“where”), sequence of events (“when”), and the content of the experience itself (“what”). Second, the code should arise instantly thereby being able to support memory formation of one‐shot experiences. For successful encoding and to avoid interference between memories during recall, variations in location, time, or in content of experience should result in unique ensemble activity. Finally, the code should capture several different resolutions of experience so that the necessary details relevant for future memory‐based predictions will be stored. We review how neuronal codes in entorhinal cortex and hippocampus follow these requirements and argue that during formation of episodic memories entorhinal cortex provides hippocampus with instant information about ongoing experience. Such information originates from (a) spatially modulated neurons in medial entorhinal cortex, including grid cells, which provide a stable and universal positional metric of the environment; (b) a continuously varying signal in lateral entorhinal cortex providing a code for the temporal progression of events; and (c) entorhinal neurons coding the content of experiences exemplified by object‐coding and odor‐selective neurons. During formation of episodic memories, information from these systems are thought to be encoded as unique sequential ensemble activity in hippocampus, thereby encoding associations between the content of an event and its spatial and temporal contexts. Upon exposure to parts of the encoded stimuli, activity in these ensembles can be reinstated, leading to reactivation of the encoded activity pattern and memory recollection.     

Utilizing Quality Improvement Methods to Examine the Radiation Therapy Pathway for Patients Requiring Palliative Radiation Therapy at a Community Cancer Center

BackgroundAt a community cancer center, during weekly quality improvement huddles, the radiation therapy team expressed stress and frustration with the pretreatment pathway for patients requiring palliative radiotherapy. As the department was meeting provincial targets with respect to wait times, it was unknown why the consensus around the department reflected discomfort and stress.MethodsFour radiation therapists formed a quality improvement project team, intent on utilizing a data-driven improvement cycle to investigate and address opportunities to improve the discomfort around this pretreatment pathway. After defining the process and identifying the customers (the health care providers operating in this pathway), the team conducted interviews with each person, transcribing answers verbatim, and grouping results by discipline. Utilizing the interview themes, each discipline identified one or two priorities to measure, as well as metrics to capture the magnitude and prevalence of these priorities.ResultsEach discipline's priorities were measured and analyzed. The identified issues brought forward at the weekly quality improvement huddles were not as prevalent as expected. Minor changes were implemented for priority issues.ConclusionThe team focused on the four principles of quality improvement: the patient, team, process, and data to address the expressed discomfort around this specific radiation therapy pathway. The results dispelled some of the myths among teams and provided solutions to areas where minor improvements were required. Utilizing the data, an evidence-informed timeline was validated, encouraging task deadlines to be more evenly distributed across the pathway. Plans to monitor this pathway are being established. The team was successful in contributing to a growing culture of continuous improvement at this community cancer center.     

2010年-2018年甲状腺结节相关SCI论文知识图谱及数据可视化分析

目的:分析2010年至2018年甲状腺结节相关SCI论文，并建模进行定性与定量分析。方法:利用文献计量学中的引文分析、共被引分析、数据可视化、聚类分析等方法，使用CiteSpace分析工具，分析来源于Web of ScienceTM核心合集数据库中有关论文的出版情况、国家、机构、作者、知识基础与研究热点。结果:到2018年10月31日截止，研究了4 618篇论文。发表论文数:美国在国家/地区中排名第一，延世大学在研究机构中排名第一，Kwak JY在所有作者中排名第一。从2010年开始，每年发表的论文数量都在稳步增长，有相当多的论文发表在如《新英格兰杂志》、《THYROID》、《JAMA》、《CELL》等高影响因子的期刊上。甲状腺结节的SCI论文参考文献聚类为6类，分别是papillary-like nuclear feature、current statu、radiofrequency ablation、ultrasound elastography、goiter area、data system。代表研究前沿的关键词是meta-analysis、recommendation、thyroid carcinoma、shear wave elastography与bethesda system。结论:本文通过对国际上甲状腺结节的研究基础、研究热点的分析，阐述了甲状腺结节的研究趋势，为我国医学工作者的研究提供参考。     

肺腺癌竞争内源性RNA网络的综合分析:基于肿瘤基因组图谱数据库

目的:基于肿瘤基因组图谱数据库（TCGA）架构肺腺癌（LUAD）竞争内源性RNA（ceRNA）网络，鉴定潜在的生存关联性生物标志物，并确定特异性治疗的小分子药物。方法:依据纳入研究标准，利用Edger软件筛选LUAD组织与正常组织(mRNA、lncRNA和miRNA)差异表达的基因。通过miRcode、miRDB、TargetScan和miRanda数据库对差异表达的RNA之间的关系进行分析，构建ceRNA网络。采用Kaplan-Meier方法分析ceRNA网络中的RNA表达量与生存预后的关系，通过富集分析对网络中的mRNA基因功能和调控通路进行分析。通过Cmap数据库筛选治疗LUAD的特异性小分子药物。利用D-lnc软件确定与关键的lncRNA相关的特异性小分子药物。结果:mRNAs(ELAVL2和PBK)、miRNAs(miR-13和miR-210)和lncRNAs(AP002478.1、DSCAM-AS1、LINC00269、LINC00470和LINC00483)与总生存期(OS)关系密切。喜树碱和甲萘醌有可能逆转LUAD的状态。卡铂、多西紫杉醇、帕比司他被确定为与关键lncRNA密切相关的药物。结论:ceRNA网络在LUAD中发挥重要作用，多种差异表达RNA与LUAD预后相关，可能成为潜在的肿瘤诊断标志物和治疗靶点。     

Monitoring changes in proteome during stepwise adaptation of a MDCK cell line from adherence to growth in suspension

Adaptation of continuous cell lines to growth in suspension in a chemically defined medium has significant advantages for design and optimization in manufacturing of biologicals. In this work, changes in the protein expression level during a step-wise adaptation of an adherent Madin Darby canine kidney (MDCK) cell line to suspension growth were analyzed. Therefore, three cell line adaptations were performed independently. Two adaptations were monitored closely to characterize short term changes in protein expression levels after serum deprivation. In addition, initial stages of suspension growth were analyzed for both adaptations. The third adaptation involved MDCK suspension cells (MDCK_SUS2) grown over an extended time period to achieve robust growth characteristics. Here, cells of the final stage of adaptation were compared with their parental cell line (MDCK_ADH). A combination of two dimensional differential gel electrophoresis for relative protein quantification and tandem mass spectrometry for protein identification enabled insights into cellular physiology. The two closely monitored cell line adaptations followed different routes regarding specific changes in protein expression but resulted in similar proteome profiles at the initial stages of suspension growth analyzed. Compared to the MDCK_ADH cells more than 90% of all changes in the protein expression level were identified after serum deprivation and were related to cytoskeletal structure, genetic information processing and cellular metabolism. Myosin proteins, involved in cellular detachment by actin-myosin contractile mechanisms were also differentially expressed. Interestingly, for both of the two adaptations, proteins linked for tumorigenicity, like lactoylglutathione lyase and sulfotransferase 1A1 were differentially expressed. In contrast, none of these proteins were differentially expressed for the MDCK_SUS2 cell line. Overall, proteomic monitoring allowed identification of key proteins involved in adaptation from adherent to suspension growth. In addition, identified proteins related to tumorigenicity may represent markers to support cell clone selection at early stages of industrial cell line development.