9,695 research outputs found
1999-00 Illinois Trapper Survey Report
Federal Aid Project Number W-112-R-9, Job Number 101.2, Wildlife Restoration FundReport issued on: January 5, 200
Toxic Algae Contamination and Demand for Shellfish: A Case Study of Demand for Mussels in Montreal
Toxic algae blooms are a worldwide phenomena, which appear to be increasing in frequency and severity. These natural events cause product contaminations that often have significant economic consequences, including supply interruptions due to closed fishing grounds, losses from human illness, and losses due to a decline in demand for the affected products. This paper evaluates the impacts of a toxic algae bloom contamination event on demand for unaffected shellfish. As an empirical example of the economic losses the shellfish industry experiences for these events, demand for mussels in Montreal is estimated using firm-level data and proxies for consumer information, during and after domoic acid contamination of Prince Edward Island mussels. Sales losses due to decreased demand are calculated. Implications of this issue for seafood safety and management policies are discussed.demand, shellfish, toxic algae, contamination, Demand and Price Analysis, Environmental Economics and Policy, Food Consumption/Nutrition/Food Safety, Resource /Energy Economics and Policy,
VALUING WATER QUALITY MONITORING: A CONTINGENT VALUATION EXPERIMENT INVOLVING HYPOTHETICAL AND REAL PAYMENTS
This paper studies the preferences and willingness-to-pay for individuals for volunteer water quality monitoring programs. The study involves supporting water quality monitoring at two ponds in the state of Rhode Island. The paper uses both a hypothetical and a real-payment contingent valuation survey to directly measure individual preferences and willingness-to-pay (WTP) for volunteer water quality monitoring at the two ponds. The overall results of the study suggest that hypothetical WTP is not statistically greater than real WTP, and that the average survey respondent is willing to support water quality monitoring on one of the two ponds. The study also finds that the specified purpose of water quality monitoring and certain socioeconomic characteristics of a respondent significantly affect the respondent's decision to support volunteer water quality monitoring.Environmental Economics and Policy,
Jet substructure and probes of CP violation in Vh production
We analyse the hVV (V = W, Z) vertex in a model independent way using Vh
production. To that end, we consider possible corrections to the Standard Model
Higgs Lagrangian, in the form of higher dimensional operators which parametrise
the effects of new physics. In our analysis, we pay special attention to linear
observables that can be used to probe CP violation in the same. By considering
the associated production of a Higgs boson with a vector boson (W or Z), we use
jet substructure methods to define angular observables which are sensitive to
new physics effects, including an asymmetry which is linearly sensitive to the
presence of CP odd effects. We demonstrate how to use these observables to
place bounds on the presence of higher dimensional operators, and quantify
these statements using a log likelihood analysis. Our approach allows one to
probe separately the hZZ and hWW vertices, involving arbitrary combinations of
BSM operators, at the Large Hadron Collider.Comment: 37 pages, 17 figures; v3 matches published versio
Three-dimensional low Reynolds number flows near biological filtering and protective layers
Mesoscale filtering and protective layers are replete throughout the natural
world. Within the body, arrays of extracellular proteins, microvilli, and cilia
can act as both protective layers and mechanosensors. For example, blood flow
profiles through the endothelial surface layer determine the amount of shear
stress felt by the endothelial cells and may alter the rates at which molecules
enter and exit the cells. Characterizing the flow profiles through such layers
is therefore critical towards understanding the function of such arrays in cell
signaling and molecular filtering. External filtering layers are also important
to many animals and plants. Trichomes (the hairs or fine outgrowths on plants)
can drastically alter both the average wind speed and profile near the leaf's
surface, affecting the rates of nutrient and heat exchange. In this paper,
dynamically scaled physical models are used to study the flow profiles outside
of arrays of cylinders that represent such filtering and protective layers. In
addition, numerical simulations using the Immersed Boundary Method are used to
resolve the 3D flows within the layers. The experimental and computational
results are compared to analytical results obtained by modeling the layer as a
homogeneous porous medium with free flow above the layer. The experimental
results show that the bulk flow is well described by simple analytical models.
The numerical results show that the spatially averaged flow within the layer is
well described by the Brinkman model. The numerical results also demonstrate
that the flow can be highly 3D with fluid moving into and out of the layer.
These effects are not described by the Brinkman model and may be significant
for biologically relevant volume fractions. The results of this paper can be
used to understand how variations in density and height of such structures can
alter shear stresses and bulk flows.Comment: 28 pages, 10 figure
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