2,439 research outputs found
First-order phase transitions in outbreaks of co-infectious diseases and the extended general epidemic process
In co-infections, positive feedback between multiple diseases can accelerate
outbreaks. In a recent letter Chen, Ghanbarnejad, Cai, and Grassberger (CGCG)
introduced a spatially homogeneous mean-field model system for such
co-infections, and studied this system numerically with focus on the possible
existence of discontinuous phase transitions. We show that their model
coincides in mean-field theory with the homogenous limit of the extended
general epidemic process (EGEP). Studying the latter analytically, we argue
that the discontinuous transition observed by CGCG is basically a spinodal
phase transition and not a first-order transition with phase-coexistence. We
derive the conditions for this spinodal transition along with predictions for
important quantities such as the magnitude of the discontinuity. We also shed
light on a true first-order transition with phase-coexistence by discussing the
EGEP with spatial inhomogeneities.Comment: 6 pages, 3 figure
Libraries and the University Press: Partners in Scholarly Communication
The University Press of Kansas is the scholarly publisher representing the six state universities of Kansas. The Press publishes monographs in a variety of academic disciplines by authors from all over the world, while also maintaining firm regional roots by publishing scholarship on the history and natural environment of Kansas, the Great Plains, and the Midwest. This article will discuss the University Press’s role in the scholarly communications ecosystem and how its mission of producing and disseminating research complements academic libraries’ efforts toward research and learning. The article will also highlight the Press’s efforts to become more engaged with its consortium schools and the Kansas academic community in general through outreach efforts and collaborative initiatives with university libraries. These include providing publishing instruction and guidance to faculty, collaborating on a joint grant application for the Humanities Open Book Program, arranging programming opportunities with Press authors, and offering publishing services not only to the six public universities but also to smaller institutions throughout the state
Comment on ``Critical behavior of a two-species reaction-diffusion problem''
In a recent paper, de Freitas et al. [Phys. Rev. E 61, 6330 (2000)] presented
simulational results for the critical exponents of the two-species
reaction-diffusion system A + B -> 2B and B -> A in dimension d = 1. In
particular, the correlation length exponent was found as \nu = 2.21(5) in
contradiction to the exact relation \nu = 2/d. In this Comment, the symmetry
arguments leading to exact critical exponents for the universality class of
this reaction-diffusion system are concisely reconsidered
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