Scale-Free Networks in Molecular Biology: Algorithms and Random Walks Analyses

dc.contributor.advisorVanRensburg, Esaias J.
dc.creatorKonini, Silva
dc.date.accessioned2018-03-01T13:57:33Z
dc.date.available2018-03-01T13:57:33Z
dc.date.copyright2017-06-16
dc.date.issued2018-03-01
dc.date.updated2018-03-01T13:57:32Z
dc.degree.disciplineMathematics & Statistics
dc.degree.levelDoctoral
dc.degree.namePhD - Doctor of Philosophy
dc.description.abstractIn this research, I focus on I) the mean field analysis of algorithms for scale-free networks in molecular biology and II) the analysis of biological networks using random walks and related algorithms. I: Many systems in nature and society are described by means of complex networks. Research indicates that these complex networks exhibit scale-free properties. Studying the organizing principles of scale-free networks has significant implications in different fields including developing better drugs, defending the internet from hackers, halting the spread of deadly epidemics, developing marketing strategies, etc. The sampling of scale-free networks in molecular biology is usually achieved by growing networks from a seed using recursive algorithms with elementary moves which include the addition and deletion of nodes and bonds. These algorithms include the Barabasi-Albert algorithm. Later algorithms, such as the Duplication-Divergence algorithm, the Sole algorithm and the iSite algorithm, were inspired by biological processes underlying the evolution of protein networks, and the networks they produce differ essentially from networks grown by the Barabasi-Albert algorithm. The mean field analysis of these algorithms is reconsidered, and extended to variant and modified implementations of the algorithms. II: The second part of this research focuses on improving biological networks using random walks and related algorithms. I use different algorithms with the goal of finding highly connected hubs and clusters of proteins which are closely related to one another. This is done by building up protein-protein interaction networks and miRNA-gene interaction networks which are then subjected to the action of two algorithms. The first algorithm used is the random walk with resistance algorithm. As an alternative, I am proposing solving the lattice laplacian on a network as a method to discover clusters of biologically related genes. These approaches seek to find ways of solving complex pathway membership problems in protein interaction databases. The clusters obtained provide more biological insight as opposed to a process of local pairwise comparison between interacting proteins. They may also predict new members in functional pathways or clusters. Underlying these algorithms are simulated biased random walks on the network for determining membership of proteins in given clusters.
dc.identifier.urihttp://hdl.handle.net/10315/34315
dc.language.isoen
dc.rightsAuthor owns copyright, except where explicitly noted. Please contact the author directly with licensing requests.
dc.subjectMolecular biology
dc.subject.keywordsApplied mathematics
dc.subject.keywordsMolecular biology
dc.subject.keywordsBioinformatics
dc.subject.keywordsMean field analysis
dc.subject.keywordsmiRNA-218-5p
dc.subject.keywordsProtein interaction networks
dc.subject.keywordsNetwork analysis
dc.subject.keywordsAlgorithms
dc.subject.keywordsLattice laplacian
dc.subject.keywordsNetwork
dc.subject.keywordsBiologial networks
dc.subject.keywordsNetwork algorithms
dc.subject.keywordsScale-free networks
dc.subject.keywordsmicroRNA-gene interaction networks
dc.subject.keywordsmiRNA
dc.subject.keywordsRandom walk
dc.subject.keywordsPower law distribution
dc.subject.keywordsDuplication-Divergence model
dc.subject.keywordsVazquez model
dc.subject.keywordsSole' model
dc.subject.keywordsiSite model
dc.subject.keywordsBarabasi-Albert model
dc.subject.keywordsScaling exponent
dc.titleScale-Free Networks in Molecular Biology: Algorithms and Random Walks Analyses
dc.typeElectronic Thesis or Dissertation

Files

Original bundle
Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
Konini_Silva_2017_PhD.pdf
Size:
54.03 MB
Format:
Adobe Portable Document Format
License bundle
Now showing 1 - 2 of 2
No Thumbnail Available
Name:
license.txt
Size:
1.83 KB
Format:
Plain Text
Description:
No Thumbnail Available
Name:
YorkU_ETDlicense.txt
Size:
3.38 KB
Format:
Plain Text
Description: