NS Seminar: Paper Presentation

Date and Location

Nov 21, 2016 - 2:00pm to 3:00pm
Network Science Lab, Bldg 434, Room 122


Taom Sakal, Ecology, Evolution, and Marine Biology Trainee
Bay Yuan Hsu, Computer Science Graduate Student


An Introduction to Sequential Dynamical Systems,

Henning S. Mortveit and Christian M. Reidys

Traditionally, all nodes update simultaneously in a dynamical system over a network. The emerging field of Sequential Dynamical Systems (SDS) questions this assumption by taking an existing dynamical system and defining an order in which nodes must update. This simple addition vastly transforms most system’s behavior.

In this presentation, we introduce SDS and why we care about them as network scientists. We then survey the field and study some choice applications, including SDS as traffic networks, genetic networks, and as a foundation for computer simulation. 


Asymmetric disease dynamics in multihost interconnected networks

Shai Pilosof, Gili Greenbaum, Boris R. Krasnov, and Yuval R. Zelnik. arXiv:1512.09178v2 [q-bio.PE] 17 Jun 2016

Epidemic spread in single-host systems strongly depends on the population's contact network. However, little is known regarding the spread of epidemics across networks representing populations of multiple hosts. We explored cross-species transmission in a multilayer network where layers represent populations of two distinct hosts, and disease can spread across intralayer (within-host) and interlayer (between-host) edges. We developed an analytic framework for the SIR epidemic model to examine the effect of (i) source of infection and (ii) between-host asymmetry in infection probabilities, on disease risk. We measured risk as outbreak probability and outbreak size in a focal host, represented by one network layer. Numeric simulations were used to validate the analytic formulations. We found that outbreak probability is determined by a complex interaction between source of infection and between-host infection probabilities, whereas outbreak size is mainly affected by the non-focal host to focal host infection probability alone. Hence, inter-specific asymmetry in infection probabilities shapes disease dynamics in multihost networks. These results expand current theory of monolayer networks, where outbreak size and probability are considered equal, highlighting the importance of considering multiple measures of disease risk. Our study advances understanding of multihost systems and non-biological systems with asymmetric flow rates.