A simulation model (STEMRUST_G, named for stem rust of grasses)
was created for stem rust (caused by Puccinia graminis subsp.
graminicola) in perennial ryegrass grown to maturity as a seed crop. The
model has a daily time step and is driven by weather data and an initial
input of disease...
Sonar techniques were used to quantitatively observe foraging predators and their prey simultaneously in three dimensions. Spinner dolphins foraged at night in highly coordinated groups of 16–28 individuals using strict four-dimensional patterns to increase prey density by up to 200 times. Herding exploited the prey’s own avoidance behavior to achieve...
The importance of large breeding individuals for maintaining the health of marine fish and invertebrate populations has long been recognized. Unfortunately, decades of human harvesting that preferentially remove larger individuals have led to drastic reductions in body sizes of many of these species. Such size-selective harvesting is particularly worrisome for...
Climate change and efforts to address it have put the electric utility system under increasing pressure to adapt and evolve. Key to the success of these efforts will be the support of public utility commissions, the state agencies that oversee retail electric utilities. In an effort to determine how these...
The Summer Coon intrusive center is located seven miles
north of Del Norte, Colorado, on the eastern edge of the San Juan
Mountains. The intrusive center is the core of a dissected calcalkaline
composite volcano of middle Oligocene age. The Summer
Coon rocks belong to the Conejos Formation which is...
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This research develops a theoretical account of cultural meanings as integral mechanisms in the normalization of credit/debt. Analysis derives these meanings from the credit/debt discourses and practices of 27 white middle-class consumers in the United States and tracks their negotiation in patterns and trajectories in social and market domains. Discussion...
Many multispecies models have assumed that prey density determines per-capita predator consumption rates, following a functional response relationship. However, empirical evidence suggests that a predator’s diet can also be influenced by a variety of environmental factors, including interactions with other predators. We used diet and abundance data from National Marine...
Seamounts are windows into the deep Earth that are helping to
elucidate various deep Earth processes. For example, thermal and mechanical
properties of oceanic lithosphere can be determined from the flexing of oceanic
crust caused by the growth of seamounts on top of it. Seamount trails also are
excellent recorders...
The hygiene hypothesis offers an explanation for the correlation, well-established in the industrialized
nations of North and West, between increased hygiene and sanitation, and increased rates of asthma and
allergies. Recent studies have added to the scope of the hypothesis, showing a link between decreased
exposure to certain bacteria and...