2,764 research outputs found
Oregon State Rank Assessment for Red Tree Vole (Arborimus longicaudus)
Oregon state conservation status assessment for Red tree vole (Arborimus longicaudus) using NatureServe methodology, 2022
The Economic Value of Rebuilding Fisheries
The global demand for protein from seafood –- whether wild, caught or cultured, whether for direct consumption or as feed for livestock –- is high and projected to continue growing. However, the ocean's ability to meet this demand is uncertain due to either mismanagement or, in some cases, lack of management of marine fish stocks. Efforts to rebuild and recover the world's fisheries will benefit from an improved understanding of the long-term economic benefits of recovering collapsed stocks, the trajectory and duration of different rebuilding approaches, variation in the value and timing of recovery for fisheries with different economic, biological, and regulatory characteristics, including identifying which fisheries are likely to benefit most from recovery, and the benefits of avoiding collapse in the first place. These questions are addressed in this paper using a dynamic bioeconomic optimisation model that explicitly accounts for economics, management, and ecology of size-structured exploited fish populations. Within this model framework, different management options (effort controls on small-, medium-, and large-sized fish) including management that optimises economic returns over a specified planning horizon are simulated and the consequences compared. The results show considerable economic gains from rebuilding fisheries, with magnitudes varying across fisheries
Elasticity of an interfacial particle raft
We study the collective behaviour of a close packed monolayer of non-Brownian
particles at a fluid-liquid interface. Such a particle raft forms a
two-dimensional elastic solid and can support anisotropic stresses and strains,
e.g. it buckles in uniaxial compression and cracks in tension. We characterise
this solid in terms of a Young's modulus and Poisson ratio derived from simple
theoretical considerations and show the validity of these estimates by using an
experimental buckling assay to deduce the Young's modulus.Comment: 7 pages, 5 figure
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