Directional dispersal plays a large role in shaping ecological processes in diverse systems such as rivers, coastlines and vegetation communities. We describe an instability driven by directional dispersal in a spatially explicit consumer–producer model where spatial patterns emerge in the absence of external environmental variation. Dispersal of the consumer has both undirected and directed co...

Since Marshall, the standard approach to developing a theory of competitive markets is to separate demand behavior (“consumer theory”) from supply behavior (“producer theory”) and then use the notion of market equilibrium to reconcile demand and supply. This note studies producer theory and a separate one studies consumer theory. The standard model has the following features. Firms are describe...

BACKGROUND Polymorphisms in transforming growth factor (TGF)-beta(1) associated with variations in cytokine levels are linked to fibrosis in a number of tissues. However, the contribution of this cytokine to organ fibrosis in patients with cystic fibrosis is presently unclear. This study was undertaken to examine the association between TGF-beta(1) gene polymorphisms and the development of pulm...

In frequency-dependent games, strategy choice may be innate or learned. While experimental evidence in the producer-scrounger game suggests that learned strategy choice may be common, a recent theoretical analysis demonstrated that learning by only some individuals prevents learning from evolving in others. Here, however, we model learning explicitly, and demonstrate that learning can easily ev...

A general review of the relevance of classical novae for the chemical evolution of the Galaxy, as well as for Galactic radioactivity is presented. A special emphasis is put on the pioneering work done by Jim Truran in this field of research. The impact of recent developments in nuclear astrophysics on nova nucleosynthesis, together with the prospects for observability of novae radioactivities w...

We analyze the incentives of a vertically-integrated producer (VIP) to engage in “self-sabotage”. Self-sabotage occurs when a VIP intentionally increases its upstream costs and/or reduces the quality of its upstream product. We identify conditions under which self-sabotage is profitable for the VIP even though it raises symmetrically the cost of the upstream product to all downstream producers ...

Introduction: Dependencies And Coordination Organizational Research Research In Artificial Intelligence And Other Fields A Framework For Studying Coordination Managing Task-Resource Dependencies Task Uses A Resource Task Produces A Resource Managing Dependencies Among Multiple Tasks And Resources Shared Resource Producer-Consumer Common Object Dependencies Between One Task And Multiple Resource...

Remote sensing indices of burn area and fire severity have been developed and tested for forest ecosystems, but not sparsely vegetated, desert shrub-steppe in which large wildfires are a common occurrence and a major issue for land management. We compared the performance of remote sensing indices for detecting burn area and fire severity with extensive ground-based cover assessments made before...

Background—Polymorphisms in transforming growth factor (TGF)-â1 associated with variations in cytokine levels are linked to fibrosis in a number of tissues. However, the contribution of this cytokine to organ fibrosis in patients with cystic fibrosis is presently unclear. This study was undertaken to examine the association between TGF-â1 gene polymorphisms and the development of pulmonary dysf...

P roducer services, a collection of business-tobusiness service industries, have become an important source of job generation across America. In fact, 9.3 million of the 30.1 million new jobs created in the United States from 1974 to 1991 were in the producer services industry, the largest growth of any broad industrial sector in the nation. Has the rural Heartland shared in this producer servi...