@inproceedings{HerajyLiuRohr, author = {Herajy, Mostafa and Liu, Fei and Rohr, Christian}, title = {Coloured hybrid Petri nets for systems biology}, series = {Proceedings of the 5th International Workshop on Biological Processes \& Petri Nets (BioPPN)}, booktitle = {Proceedings of the 5th International Workshop on Biological Processes \& Petri Nets (BioPPN)}, editor = {Heiner, Monika}, pages = {60 -- 76}, language = {en} } @inproceedings{LiuHeiner, author = {Liu, Fei and Heiner, Monika}, title = {Coloured Petri Nets to Model and simulate Biological Systems}, series = {Proceedings of the Workshops of the 31st International Conference on Application and Theory of Petri Nets and Other Models of Concurrency (PETRI NETS 2010)}, booktitle = {Proceedings of the Workshops of the 31st International Conference on Application and Theory of Petri Nets and Other Models of Concurrency (PETRI NETS 2010)}, pages = {70 -- 84}, language = {en} } @misc{LiuAssafChenetal., author = {Liu, Fei and Assaf, George and Chen, Ming and Heiner, Monika}, title = {A Petri nets-based framework for whole-cell modeling}, series = {Biosystems}, volume = {210}, journal = {Biosystems}, issn = {0303-2647}, doi = {10.1016/j.biosystems.2021.104533}, abstract = {Whole-cell modeling aims to incorporate all main genes and processes, and their interactions of a cell in one model. Whole-cell modeling has been regarded as the central aim of systems biology but also as a grand challenge, which plays essential roles in current and future systems biology. In this paper, we analyze whole-cell modeling challenges and requirements and classify them into three aspects (or dimensions): heterogeneous biochemical networks, uncertainties in components, and representation of cell structure. We then explore how to use different Petri net classes to address different aspects of whole-cell modeling requirements. Based on these analyses, we present a Petri nets-based framework for whole-cell modeling, which not only addresses many whole-cell modeling requirements, but also offers a graphical, modular, and hierarchical modeling tool. We think this framework can offer a feasible modeling approach for whole-cell model construction.}, language = {en} } @misc{AssafHeinerLiu, author = {Assaf, George and Heiner, Monika and Liu, Fei}, title = {Colouring Fuzziness for Systems Biology}, series = {Theoretical Computer Science}, volume = {875}, journal = {Theoretical Computer Science}, issn = {1879-2294}, doi = {10.1016/j.tcs.2021.04.011}, pages = {52 -- 64}, abstract = {Snoopy is a powerful modelling and simulation tool for various types of Petri nets, which have been applied to a wide range of biochemical reaction networks. We present an enhanced version of Snoopy, now supporting coloured and uncoloured stochastic, continuous and hybrid Petri Nets with fuzzy kinetic parameters. Colour helps to cope with modelling challenges imposed by larger and more complex networks. Fuzzy parameters are specifically useful when kinetic parameter values can not be precisely measured or estimated. By running fuzzy simulation we obtain output bands of the variables of interest induced by the effect of the fuzzy kinetic parameters. Simulation is always done on the uncoloured level. For this purpose, coloured fuzzy Petri nets are automatically unfolded to their corresponding uncoloured counterparts. Combining the power of fuzzy kinetic parameters with the modelling convenience of coloured Petri nets provides a new quality in user support with sophisticated modelling and analysis features.}, language = {en} } @misc{AssafHeinerLiu, author = {Assaf, George and Heiner, Monika and Liu, Fei}, title = {Coloured fuzzy Petri nets for modelling and analysing membrane systems}, series = {Biosystems}, volume = {212}, journal = {Biosystems}, issn = {0303-2647}, doi = {10.1016/j.biosystems.2021.104592}, pages = {1 -- 10}, abstract = {Membrane systems are a very powerful computational modelling formalism inspired by the internal organisation of living cells. Modelling of membrane systems is challenged by composing many structurally similar components, which may result in very large models. Furthermore, some components may suffer from a lack of precise kinetic parameters. Coloured fuzzy Petri nets combine coloured Petri nets with fuzzy kinetic parameters, and thus offer an approach to address these challenges. In this paper, we use coloured fuzzy Petri nets to model and simulate membrane systems which are enriched by fuzzy kinetic parameters. We also introduce a methodology and workflow utilising coloured fuzzy Petri nets for modelling and simulating general biological systems which have to cope with incomplete knowledge of their kinetic data.}, language = {en} } @misc{LiuSunHeineretal., author = {Liu, Fei and Sun, Wujie and Heiner, Monika and Gilbert, David}, title = {Hybrid modelling of biological systems using fuzzy continuous Petri nets}, series = {Briefings in Bioinformatics}, volume = {22(2021)}, journal = {Briefings in Bioinformatics}, doi = {10.1093/bib/bbz114}, pages = {438 -- 450}, abstract = {Integrated modelling of biological systems is challenged by composing components with sufficient kinetic data and components with insufficient kinetic data or components built only using experts' experience and knowledge. Fuzzy continuous Petri nets (FCPNs) combine continuous Petri nets with fuzzy inference systems, and thus offer an hybrid uncertain/certain approach to integrated modelling of such biological systems with uncertainties. In this paper, we give a formal definition and a corresponding simulation algorithm of FCPNs, and briefly introduce the FCPN tool that we have developed for implementing FCPNs. We then present a methodology and workflow utilizing FCPNs to achieve hybrid (uncertain/certain) modelling of biological systems illustrated with a case study of the Mercaptopurine metabolic pathway. We hope this research will promote the wider application of FCPNs and address the uncertain/certain integrated modelling challenge in the systems biology area.}, language = {en} } @misc{LiuHeinerGilbert, author = {Liu, Fei and Heiner, Monika and Gilbert, David}, title = {Fuzzy Petri nets for modelling of uncertain biological systems}, series = {Briefings in Bioinformatics}, volume = {2018}, journal = {Briefings in Bioinformatics}, issn = {1477-4054}, doi = {10.1093/bib/bby118}, pages = {13}, language = {en} } @misc{AssafHeinerLiu, author = {Assaf, George and Heiner, Monika and Liu, Fei}, title = {Biochemical reaction networks with fuzzy kinetic parameters in Snoopy}, series = {Computational Methods in Systems Biology : 17th International Conference, CMSB 2019, Trieste, Italy, September 18-20, 2019, Proceedings}, journal = {Computational Methods in Systems Biology : 17th International Conference, CMSB 2019, Trieste, Italy, September 18-20, 2019, Proceedings}, editor = {Bortolussi, Luca and Sanguinetti, Guido}, publisher = {Springer}, isbn = {978-3-030-31303-6}, doi = {http://dx.doi.org/10.1007/978-3-030-31304-3_17}, pages = {302 -- 307}, language = {en} } @phdthesis{Liu, author = {Liu, Fei}, title = {Colored Petri Nets for Systems Biology}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:co1-opus-23656}, pages = {XVI, 158}, language = {en} }