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Inference of General Mass Action-Based State Equations for Oscillatory Biochemical Reaction Systems Using <i>k</i>-Step Genetic Programming 被引量:1
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作者 Tatsuya Sekiguchi Hiroyuki Hamada Masahiro Okamoto 《Applied Mathematics》 2019年第8期627-645,共19页
Systems biology requires the development of algorithms that use omics data to infer interaction networks among biomolecules working within an organism. One major type of evolutionary algorithm, genetic programming (GP... Systems biology requires the development of algorithms that use omics data to infer interaction networks among biomolecules working within an organism. One major type of evolutionary algorithm, genetic programming (GP), is useful for its high heuristic ability as a search method for obtaining suitable solutions expressed as tree structures. However, because GP determines the values of parameters such as coefficients by random values, it is difficult to apply in the inference of state equations that describe oscillatory biochemical reaction systems with high nonlinearity. Accordingly, in this study, we propose a new GP procedure called “k-step GP” intended for inferring the state equations of oscillatory biochemical reaction systems. The k-step GP procedure consists of two algorithms: 1) Parameter optimization using the modified Powell method—after genetic operations such as crossover and mutation, the values of parameters such as coefficients are optimized by applying the modified Powell method with secondary convergence. 2) GP using divided learning data—to improve the inference efficiency, imposes perturbations through the addition of learning data at various intervals and adaptations to these changes result in state equations with higher fitness. We are confident that k-step GP is an algorithm that is particularly well suited to inferring state equations for oscillatory biochemical reaction systems and contributes to solving inverse problems in systems biology. 展开更多
关键词 SYSTEMS Biology Genetic Programming Inverse Problems OSCILLATORY BIOCHEMICAL Reaction SYSTEMS GMA-Based State Equations
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Expanded Relative Operator Entropies and Operator Valued α-Divergence
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作者 Hiroshi Isa Masatoshi Ito +2 位作者 Eizaburo Kamei Hiroaki Tohyama MasayukiWatanabe 《Journal of Mathematics and System Science》 2015年第6期215-224,共10页
关键词 正算子 相对熵 本质特性 幂平均 S算子 Rb 几何 ST
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基于内在功能连接推定抑郁症脑网络效率的改变(英文) 被引量:2
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作者 李淮周 周海燕 +3 位作者 杨阳 杨孝敬 王海渊 钟宁 《生物化学与生物物理进展》 SCIE CAS CSCD 北大核心 2018年第1期43-50,共8页
本文研究了在保留最大化内在功能连接条件下抑郁症患者脑网络效率的改变,并探索了改变的拓扑效率和抑郁症病理学之间的关系.为此,我们收集了20例抑郁症患者和20例在年龄、性别和教育水平相匹配的健康被试的静息态功能磁共振图像数据.图... 本文研究了在保留最大化内在功能连接条件下抑郁症患者脑网络效率的改变,并探索了改变的拓扑效率和抑郁症病理学之间的关系.为此,我们收集了20例抑郁症患者和20例在年龄、性别和教育水平相匹配的健康被试的静息态功能磁共振图像数据.图论分析显示,与健康对照组比较,抑郁症患者的节点效率减少在左海马旁回、右杏仁核,左颞横回和左颞极(颞中回)减少.减少的节点效率表明,在抑郁症患者脑网络中这些区域传送信息到其他区域的能力减弱.此外,发现局部效率降低在左内侧额上回、左眶部额上回、右回直肌、左杏仁核、右顶上回、左丘脑和左颞极(颞中回).并且发现左内侧额上回、左杏仁核、左丘脑与PHQ-9得分呈负相关.降低的局部效率表明抑郁症患者脑网络中这些区域的局部网络信息传送能力受到抑制.这些结果进一步确认在抑郁症患者中涉及情感信息处理的前额-丘脑-边缘区域被破坏.我们的发现为抑郁症病人的辅助诊断提供了新的潜在生物学标记物. 展开更多
关键词 抑郁症 静息态功能磁共振 网络效率 图论
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Neural substrates of data-driven scientific discovery:An fMRI study during performance of number series completion task 被引量:8
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作者 ZHONG Ning LIANG PeiPeng +3 位作者 QIN YuLin LU ShengFu YANG YanHui LI KunCheng 《Science China(Life Sciences)》 SCIE CAS 2011年第5期466-473,共8页
Although much has been known about how humans psychologically perform data-driven scientific discovery,less has been known about its brain mechanism.The number series completion is a typical data-driven scientific dis... Although much has been known about how humans psychologically perform data-driven scientific discovery,less has been known about its brain mechanism.The number series completion is a typical data-driven scientific discovery task,and has been demonstrated to possess the priming effect,which is attributed to the regularity identification and its subsequent extrapolation.In order to reduce the heterogeneities and make the experimental task proper for a brain imaging study,the number magnitude and arithmetic operation involved in number series completion tasks are further restricted.Behavioral performance in Experiment 1 shows the reliable priming effect for targets as expected.Then,a factorial design (the priming effect:prime vs.target;the period length:simple vs.complex) of event-related functional magnetic resonance imaging (fMRI) is used in Experiment 2 to examine the neural basis of data-driven scientific discovery.The fMRI results reveal a double dissociation of the left DLPFC (dorsolateral prefrontal cortex) and the left APFC (anterior prefrontal cortex) between the simple (period length=1) and the complex (period length=2) number series completion task.The priming effect in the left DLPFC is more significant for the simple task than for the complex task,while the priming effect in the left APFC is more significant for the complex task than for the simple task.The reliable double dissociation may suggest the different roles of the left DLPFC and left APFC in data-driven scientific discovery.The left DLPFC (BA 46) may play a crucial role in rule identification,while the left APFC (BA 10) may be related to mental set maintenance needed during rule identification and extrapolation. 展开更多
关键词 功能磁共振成像 科学发现 数据驱动 数字系列 神经 APFC 基板 启动效应
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Normalized MEDLINE Distance in Context-Aware Life Science Literature Searches
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作者 王岩 王丛 +5 位作者 曾毅 黄智生 Vassil Momtchev Bo Andersson 任旭 钟宁 《Tsinghua Science and Technology》 SCIE EI CAS 2010年第6期709-715,共7页
Literature searches on the Web result in great volumes of query results. A model is presented here to refine the search process using user interests. User interests are analyzed to calculate semantic similarity among ... Literature searches on the Web result in great volumes of query results. A model is presented here to refine the search process using user interests. User interests are analyzed to calculate semantic similarity among the interest terms to refine the query. Traditional general purpose similarity measures may not always fit a domain specific context. This paper presents a similarity method for medical literature searches based on the biomedical literature knowledge source "MEDLINE", the normalized MEDLINE distance, to more reasonably reflect the relevance between medical terms. This measure gives more accurate user interest descriptions through calculating the similarities of user interest terms to rerank the interest term list. The accurate user interest descriptions can be used for query refinement in keyword searches to give more personalized results for the user. This measure also improves the search results for personalization through controlling the return number of results on each topic of interest. 展开更多
关键词 semantic similarity query refinement user interest context-aware search
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数据驱动的科学发现的神经机制:一项fMRI研究 被引量:6
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作者 钟宁 梁佩鹏 +3 位作者 秦裕林 吕胜富 杨延辉 李坤成 《中国科学(C辑)》 CSCD 北大核心 2009年第3期271-278,共8页
作为人脑的一种高级认知功能,数据驱动的科学发现的神经机制仍不清楚.数列完型任务是一种典型的数据驱动的科学发现任务,一些研究已经证实了数列完型任务中的启动效应,并将其归因于规则发现及其应用这一核心成分.为了降低实验任务的异... 作为人脑的一种高级认知功能,数据驱动的科学发现的神经机制仍不清楚.数列完型任务是一种典型的数据驱动的科学发现任务,一些研究已经证实了数列完型任务中的启动效应,并将其归因于规则发现及其应用这一核心成分.为了降低实验任务的异质性并使得实验任务适于进行脑成像研究,本文对数列完型任务中的数字大小及运算规则进行了进一步的约束.与预期一致,行为实验一显示了稳定的启动效应.在实验一的基础上,实验二采用事件相关fMRI研究数据驱动的科学发现的脑机制.fMRI结果揭示了左侧DLPFC(背外侧前额)和左侧APFC(前额前部)对于简单和复杂数列完型任务的双分离.简单任务在左侧DLPFC的启动效应强于复杂任务,而复杂任务在左侧APFC的启动效应强于简单任务.这一双分离说明了左侧DLPFC和左侧APFC在数据驱动的科学发现中的不同作用.左侧DLPFC(BA46)可能与规则识别有关,而左侧APFC(BA10)可能与规则识别与应用过程中的心理状态保持有关. 展开更多
关键词 背外侧前额 功能磁共振 数据驱动的科学发现 数列完型
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DLPFC在MCI患者和正常老年人归纳推理过程中的作用:一项fMRI研究 被引量:6
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作者 杨延辉 梁佩鹏 +2 位作者 吕胜富 李坤成 钟宁 《中国科学(C辑)》 CSCD 北大核心 2009年第7期711-716,共6页
以往对青年人被试的研究发现,左侧背外侧前额(DLPFC)在归纳推理过程中起着非常重要的作用.本研究使用功能磁共振成像(fMRI)考查这一脑区是否也在轻度认知障碍(MCI)患者及正常老年人进行归纳推理时被显著激活,以及MCI患者和正常老年人在... 以往对青年人被试的研究发现,左侧背外侧前额(DLPFC)在归纳推理过程中起着非常重要的作用.本研究使用功能磁共振成像(fMRI)考查这一脑区是否也在轻度认知障碍(MCI)患者及正常老年人进行归纳推理时被显著激活,以及MCI患者和正常老年人在激活模式上是否存在差异.实验结果发现,与正常老年人相比,MCI患者在行为数据(反应时和正确率)和DLPFC的激活模式上没有差异,但MCI患者DLPFC的BOLD信号强度低于正常老年人,双侧DLPFC的功能连接强度显著高于正常老年人.这可能是由于MCI患者在DLPFC的功能减弱,因而需要加强与对侧脑区的协同来完成认知加工.总之,这一结果表明,与青年人一样,DLPFC在老年人的归纳推理中也起着重要作用,而且DLPFC功能的改变可能是一个先于影像学形态结构改变的MCI的早期诊断标记. 展开更多
关键词 轻度认知功能障碍 功能磁共振成像 归纳推理
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Parietal cortex contributions to information granules following memory consolidation 被引量:1
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作者 WANG XiuZhen ZHONG Ning +2 位作者 LU ShengFu LI KunCheng LANG ShuLei 《Chinese Science Bulletin》 SCIE EI CAS 2010年第24期2671-2676,共6页
Previous studies have focused on changes in cerebral cortex activity accompanying memory formation and consolidation.Although the role of the parietal cortex in memory retrieval is well established,it is not well unde... Previous studies have focused on changes in cerebral cortex activity accompanying memory formation and consolidation.Although the role of the parietal cortex in memory retrieval is well established,it is not well understood how parietal cortex memory consolidation for mathematical rules is related to granularity of stored information(i.e.,degree of detail or precision).Changes in parietal cortex activity associated with memory consolidation were analyzed using the Ebbinghaus paradigm and functional magnetic resonance imaging(fMRI).Over the course of 1 week,participants learned Boolean arithmetic tasks involving stimulus-response mapping rules containing either low-or high-granularity information.FMRI images were collected on day 1(i.e., low-granularity condition)and day 7(i.e.,high-granularity condition).The present data suggested that with practice,stored information was converted from a low-granularity to a high-granularity form.By following rule learning,it was hypothesized that the process of consolidation would involve an increased degree of rule representation granularity.Evidence for this process was reflected in parietal cortex activity.This finding was consistent with the hypothesis that mnemonic reconstruction in the parietal cortex is required for memory consolidation,and results suggested that information granules are formed during memory consolidation.The present results could increase the understanding of the relationship between memory consolidation and information granularity. 展开更多
关键词 信息颗粒 大脑皮质 记忆 功能性磁共振成像 信息粒度 功能磁共振成像 大肠杆菌 FMRI
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Culture versus Policy: More Global Collaboration to Effectively Combat COVID-19
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作者 Jianping Li Kun Guo +10 位作者 Enrique Herrera Viedma Heesoek Lee Jiming Liu Ning Zhong Luiz Flavio Autran Monteiro Gomes Florin Gheorghe Filip Shu-Cherng Fang Mujgan SagirÖzdemir Xiaohui Liu Guoqing Lu Yong Shi 《The Innovation》 2020年第2期15-16,共2页
The outbreak of COVID-19 seriously challenges every government with regard to capacity and management of public health systems facing the catastrophic emergency.Culture and anti-epidemic policy do not necessarily conf... The outbreak of COVID-19 seriously challenges every government with regard to capacity and management of public health systems facing the catastrophic emergency.Culture and anti-epidemic policy do not necessarily conflict with each other.All countries and governments should be more tolerant to each other in seeking cultural and political consensus to overcome this historically tragic pandemic together. 展开更多
关键词 SEEKING OVERCOME POLICY
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