While it is crucial to understand the factors that determine the biodiversity of primary producer communities, the relative importance of bottom-up and top-down control factors is still poorly understood. Using freshwater benthic algal communities in the laboratory as a model system, we find an unimodal relationship between nutrient availability and producer diversity, and that increasing numbe...

Since fossil fuel subsidies entail significant economic, fiscal, social and environmental costs, more and more attention is being paid to phasing out fossil fuel subsidies. The OECD has recently completed a report quantifying the amount of both producer and consumer subsidies for their member countries, and some work has been implemented on analyzing the effects of consumer subsidy removal. How...

An attractive feature of competitive markets is that they maximize the sum of consumer and producer surplus. Producer and consumer surplus are shown in the market supply and market demand diagram in Figure 7-4. Recall that the producer surplus for all producers is the area above the supply curve and below the market price line, and that the consumer surplus for all consumers is the area below t...

Producer diversity is frequently assumed to be detrimental to herbivores, because less edible taxa are more likely to dominate diverse communities. Many producers are, however, complementary in their resource use, and primary production is often positively related to producer diversity. We performed an experiment with microalgae and a generalist herbivore to explore the hypothesis that such pos...

The producer-consumer model is a classic synchronization problem, exploring the division of labor between threads. Producers are responsible for creating or yielding items of some kind, while consumers are responsible for processing these items. The producer-consumer model is present in a wide array of multithreaded applications. It is commonly used to read data from high-throughput streaming A...

An A∞-bialgebra is a DGM H equipped with structurally compatible operations { ω : H → H } such that ( H, ω ) is an A∞-algebra and ( H, ω ) is an A∞-coalgebra. Structural compatibility is controlled by the biderivative operator Bd, defined in terms of two kinds of cup products on certain cochain algebras of pemutahedra over the universal PROP U = End (TH). To Jim Stasheff on the occasion of his ...

Cancer cells secrete growth factors that induce proliferation, protect against apoptosis and the immune system or promote neo-angiogenesis [1]. As they are diffusible (Fig. 1), the growth factors produced by a cell can be used by other neighbouring cells, an example of cooperation among cancer cells [2]. A conceptual problem arises: a non-producer cell can exploit the growth factors secreted by...