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在一个对节点(node)和边(edge)以量化标注的网络中,'''活动模体'''是<font color="red">反复</font>的斑图。例如,当新城代谢的边以相应基因的表达量或<font color="red">时间</font>来标注时,一些斑图在'''给定的'''底层网络结构里<font color="red">是反复的</font>。<ref name="agc">{{cite journal |vauthors=Chechik G, Oh E, Rando O, Weissman J, Regev A, Koller D |title=Activity motifs reveal principles of timing in transcriptional control of the yeast metabolic network |journal=Nat. Biotechnol. |volume=26 |issue=11 |pages=1251–9 |date=November 2008 |pmid=18953355 |pmc=2651818 |doi=10.1038/nbt.1499}}</ref>
 
在一个对节点(node)和边(edge)以量化标注的网络中,'''活动模体'''是<font color="red">反复</font>的斑图。例如,当新城代谢的边以相应基因的表达量或<font color="red">时间</font>来标注时,一些斑图在'''给定的'''底层网络结构里<font color="red">是反复的</font>。<ref name="agc">{{cite journal |vauthors=Chechik G, Oh E, Rando O, Weissman J, Regev A, Koller D |title=Activity motifs reveal principles of timing in transcriptional control of the yeast metabolic network |journal=Nat. Biotechnol. |volume=26 |issue=11 |pages=1251–9 |date=November 2008 |pmid=18953355 |pmc=2651818 |doi=10.1038/nbt.1499}}</ref>
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==Criticism==
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==批判 Criticism==
 
An assumption (sometimes more sometimes less implicit) behind the preservation of a topological sub-structure is that it is of a particular functional importance. This assumption has recently been questioned. Some authors have argued that motifs, like ''bi-fan motifs'', might show a variety depending on the network context, and therefore,<ref name="ad">{{cite journal |vauthors=Ingram PJ, Stumpf MP, Stark J |title=Network motifs: structure does not determine function |journal=BMC Genomics |volume=7 |pages=108 |year=2006 |pmid=16677373 |pmc=1488845 |doi=10.1186/1471-2164-7-108 }} {{open access}}</ref> structure of the motif does not necessarily determine function. Network structure certainly does not always indicate function; this is an idea that has been around for some time, for an example see the Sin operon.<ref>{{cite journal |vauthors=Voigt CA, Wolf DM, Arkin AP |title=The ''Bacillus subtilis'' sin operon: an evolvable network motif |journal=Genetics |volume=169 |issue=3 |pages=1187–202 |date=March 2005 |pmid=15466432 |pmc=1449569 |doi=10.1534/genetics.104.031955 |url=http://www.genetics.org/cgi/pmidlookup?view=long&pmid=15466432}}</ref>
 
An assumption (sometimes more sometimes less implicit) behind the preservation of a topological sub-structure is that it is of a particular functional importance. This assumption has recently been questioned. Some authors have argued that motifs, like ''bi-fan motifs'', might show a variety depending on the network context, and therefore,<ref name="ad">{{cite journal |vauthors=Ingram PJ, Stumpf MP, Stark J |title=Network motifs: structure does not determine function |journal=BMC Genomics |volume=7 |pages=108 |year=2006 |pmid=16677373 |pmc=1488845 |doi=10.1186/1471-2164-7-108 }} {{open access}}</ref> structure of the motif does not necessarily determine function. Network structure certainly does not always indicate function; this is an idea that has been around for some time, for an example see the Sin operon.<ref>{{cite journal |vauthors=Voigt CA, Wolf DM, Arkin AP |title=The ''Bacillus subtilis'' sin operon: an evolvable network motif |journal=Genetics |volume=169 |issue=3 |pages=1187–202 |date=March 2005 |pmid=15466432 |pmc=1449569 |doi=10.1534/genetics.104.031955 |url=http://www.genetics.org/cgi/pmidlookup?view=long&pmid=15466432}}</ref>
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关于拓扑子结构的一个(某种程度上隐含的)前提性假设是其具有特定的功能重要性。但这个假设最近遭到质疑,有人提出在不同的网络环境下模体可能表现出多样性,例如双扇模体,所以<ref name="ad">{{cite journal |vauthors=Ingram PJ, Stumpf MP, Stark J |title=Network motifs: structure does not determine function |journal=BMC Genomics |volume=7 |pages=108 |year=2006 |pmid=16677373 |pmc=1488845 |doi=10.1186/1471-2164-7-108 }} {{open access}}</ref>模体的结构不必然决定功能,网络结构也不当然能揭示其功能;这种见解由来已久,可参见<font color="red">Sin 操纵子</font>。<ref>{{cite journal |vauthors=Voigt CA, Wolf DM, Arkin AP |title=The ''Bacillus subtilis'' sin operon: an evolvable network motif |journal=Genetics |volume=169 |issue=3 |pages=1187–202 |date=March 2005 |pmid=15466432 |pmc=1449569 |doi=10.1534/genetics.104.031955 |url=http://www.genetics.org/cgi/pmidlookup?view=long&pmid=15466432}}</ref>
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Most analyses of motif function are carried out looking at the motif operating in isolation. Recent research<ref>{{cite journal |vauthors=Knabe JF, Nehaniv CL, Schilstra MJ |title=Do motifs reflect evolved function?—No convergent evolution of genetic regulatory network subgraph topologies |journal=BioSystems |volume=94 |issue=1–2 |pages=68–74 |year=2008 |pmid=18611431 |doi=10.1016/j.biosystems.2008.05.012 }}</ref> provides good evidence that network context, i.e. the connections of the motif to the rest of the network, is too important to draw inferences on function from local structure only — the cited paper also reviews the criticisms and alternative explanations for the observed data. An analysis of the impact of a single motif module on the global dynamics of a network is studied in.<ref>{{cite journal |vauthors=Taylor D, Restrepo JG |title=Network connectivity during mergers and growth: Optimizing the addition of a module |journal=Physical Review E |volume=83 |issue=6 |year=2011 |page=66112 |doi=10.1103/PhysRevE.83.066112 |pmid=21797446 |bibcode=2011PhRvE..83f6112T |arxiv=1102.4876 }}</ref> Yet another recent work suggests that certain topological features of biological networks naturally give rise to the common appearance of canonical motifs, thereby questioning whether frequencies of occurrences are reasonable evidence that the structures of motifs are selected for their functional contribution to the operation of networks.<ref>{{cite journal|last1=Konagurthu|first1=Arun S.|last2=Lesk|first2=Arthur M.|title=Single and multiple input modules in regulatory networks|journal=Proteins: Structure, Function, and Bioinformatics|date=23 April 2008|volume=73|issue=2|pages=320–324|doi=10.1002/prot.22053|pmid=18433061}}</ref><ref>{{cite journal |vauthors=Konagurthu AS, Lesk AM |title=On the origin of distribution patterns of motifs in biological networks |journal=BMC Syst Biol |volume=2 |pages=73 |year=2008 |pmid=18700017 |pmc=2538512 |doi=10.1186/1752-0509-2-73 }} {{open access}}</ref>
 
Most analyses of motif function are carried out looking at the motif operating in isolation. Recent research<ref>{{cite journal |vauthors=Knabe JF, Nehaniv CL, Schilstra MJ |title=Do motifs reflect evolved function?—No convergent evolution of genetic regulatory network subgraph topologies |journal=BioSystems |volume=94 |issue=1–2 |pages=68–74 |year=2008 |pmid=18611431 |doi=10.1016/j.biosystems.2008.05.012 }}</ref> provides good evidence that network context, i.e. the connections of the motif to the rest of the network, is too important to draw inferences on function from local structure only — the cited paper also reviews the criticisms and alternative explanations for the observed data. An analysis of the impact of a single motif module on the global dynamics of a network is studied in.<ref>{{cite journal |vauthors=Taylor D, Restrepo JG |title=Network connectivity during mergers and growth: Optimizing the addition of a module |journal=Physical Review E |volume=83 |issue=6 |year=2011 |page=66112 |doi=10.1103/PhysRevE.83.066112 |pmid=21797446 |bibcode=2011PhRvE..83f6112T |arxiv=1102.4876 }}</ref> Yet another recent work suggests that certain topological features of biological networks naturally give rise to the common appearance of canonical motifs, thereby questioning whether frequencies of occurrences are reasonable evidence that the structures of motifs are selected for their functional contribution to the operation of networks.<ref>{{cite journal|last1=Konagurthu|first1=Arun S.|last2=Lesk|first2=Arthur M.|title=Single and multiple input modules in regulatory networks|journal=Proteins: Structure, Function, and Bioinformatics|date=23 April 2008|volume=73|issue=2|pages=320–324|doi=10.1002/prot.22053|pmid=18433061}}</ref><ref>{{cite journal |vauthors=Konagurthu AS, Lesk AM |title=On the origin of distribution patterns of motifs in biological networks |journal=BMC Syst Biol |volume=2 |pages=73 |year=2008 |pmid=18700017 |pmc=2538512 |doi=10.1186/1752-0509-2-73 }} {{open access}}</ref>
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大多数模体功能分析是基于模体孤立运行的情形。最近的研究表明网络环境至关重要,不能忽视网络环境而仅从本地结构来对其功能进行推论——引用的论文还回顾了对观测数据的批判及其他可能的解释。人们研究了单个模体模组对网络全局的动力学影响及其分析。而另一项近期的研究工作提出生物网络的某些拓扑特征自然地引起经典模体的常见形态,让人不禁疑问:发生频率是否能证明模体的结构是出于其对所在网络运行的功能性贡献而被保留下的结果?
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While the study of motifs was mostly applied to static complex networks, research of temporal complex networks<ref>Braha, D., & Bar‐Yam, Y. (2006). [https://static1.squarespace.com/static/5b68a4e4a2772c2a206180a1/t/5c5de3faf4e1fc43e7b3d21e/1549657083988/Complexity_Braha_Original_w_Cover.pdf From centrality to temporary fame: Dynamic centrality in complex networks]. Complexity, 12(2), 59-63. </ref> suggested a significant reinterpretation of network motifs, and introduced the concept of '''temporal network motifs'''. Braha and Bar-Yam<ref> Braha D., Bar-Yam Y. (2009) [https://s3.amazonaws.com/academia.edu.documents/4892116/Adaptive_Networks__Theory__Models_and_Applications__Understanding_Complex_Systems_.pdf?response-content-disposition=inline%3B%20filename%3DRedes_teoria.pdf&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAIWOWYYGZ2Y53UL3A%2F20191111%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20191111T173250Z&X-Amz-Expires=3600&X-Amz-SignedHeaders=host&X-Amz-Signature=89d08c9e92b88ed817e4eb0f87c480757ef79c4b865919a5e0890cbefa164c61#page=55 Time-Dependent Complex Networks: Dynamic Centrality, Dynamic Motifs, and Cycles of Social Interactions]. In: Gross T., Sayama H. (eds) Adaptive Networks. Understanding Complex Systems. Springer, Berlin, Heidelberg </ref> studied the dynamics of local motif structure in time-dependent/temporal networks, and find recurrent patterns that might provide empirical evidence for cycles of social interaction. Counter to the perspective of stable motifs and motif profiles in complex networks, they demonstrated that for temporal networks the local structure is time-dependent and might evolve over time. Braha and Bar-Yam further suggested that analyzing the temporal local structure might provide important information about the dynamics of system-level task and functionality.
 
While the study of motifs was mostly applied to static complex networks, research of temporal complex networks<ref>Braha, D., & Bar‐Yam, Y. (2006). [https://static1.squarespace.com/static/5b68a4e4a2772c2a206180a1/t/5c5de3faf4e1fc43e7b3d21e/1549657083988/Complexity_Braha_Original_w_Cover.pdf From centrality to temporary fame: Dynamic centrality in complex networks]. Complexity, 12(2), 59-63. </ref> suggested a significant reinterpretation of network motifs, and introduced the concept of '''temporal network motifs'''. Braha and Bar-Yam<ref> Braha D., Bar-Yam Y. (2009) [https://s3.amazonaws.com/academia.edu.documents/4892116/Adaptive_Networks__Theory__Models_and_Applications__Understanding_Complex_Systems_.pdf?response-content-disposition=inline%3B%20filename%3DRedes_teoria.pdf&X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=AKIAIWOWYYGZ2Y53UL3A%2F20191111%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20191111T173250Z&X-Amz-Expires=3600&X-Amz-SignedHeaders=host&X-Amz-Signature=89d08c9e92b88ed817e4eb0f87c480757ef79c4b865919a5e0890cbefa164c61#page=55 Time-Dependent Complex Networks: Dynamic Centrality, Dynamic Motifs, and Cycles of Social Interactions]. In: Gross T., Sayama H. (eds) Adaptive Networks. Understanding Complex Systems. Springer, Berlin, Heidelberg </ref> studied the dynamics of local motif structure in time-dependent/temporal networks, and find recurrent patterns that might provide empirical evidence for cycles of social interaction. Counter to the perspective of stable motifs and motif profiles in complex networks, they demonstrated that for temporal networks the local structure is time-dependent and might evolve over time. Braha and Bar-Yam further suggested that analyzing the temporal local structure might provide important information about the dynamics of system-level task and functionality.
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模体的研究主要应用于静态复杂网络,而时序复杂网络的研究对网络模体的提出了重大的新解释,并介绍了时变网络模体的概念。Braha和Bar-Yam研究了
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本地模体结构在时间依赖网络/时变网络的动力学,发现的一些反复模式有望成为社会互动周期的经验论据。他们证明了对于时变网络,其本地结构是时间依赖的且可能随时间演变,作为对复杂网络中稳定模体观及的模体表达观的反论,Braha和Bar-Yam进一步提出,时变本地结构的分析可能提供关于系统级任务和功能的动力信息重要信息。
    
==See also==
 
==See also==
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