A Runge-Kutta method has been developed to minimize the global
error in the numerical solution of certain classes of differential
equations problems. The distinguishing feature of the method
is that the coefficients of the numerical integration formula
depend on the initial conditions present at the time of solution.
The method...
Sediments on the inner portion of the Oregon continental shelf
consist of clean, well-sorted, detrital sand. This sand has an average
median diameter of 2.53Φ (. 173 mm) and is both positively and
negatively skewed. Deposits with median diameters in the coarse
sand and gravel classes occur at depths of...
Dormancy is a key life history trait of planktonic calanoid copepods in the genus
Calanus. Empirical evidence suggests that duration of dormancy is controlled by
ambient temperature driving lipid metabolism in individuals. Here, we use the
temperature-dependent metabolic rates of overwintering individuals to show that
increasing temperatures, associated with global...
From the planning days preceding the establishment of the US Global
Ocean Ecosystem Dynamics (GLOBEC) program, modeling was recognized as one
of the program’s pillars. In particular, predictions of future ecosystem states in an
evolving climate system required new interdisciplinary approaches that brought
together physicists, biologists, modelers, and observational scientists....
The 20-year US GLOBEC (Global Ocean Ecosystem Dynamics)
program examined zooplankton populations and their predators in four coastal
marine ecosystems. Program scientists learned that environmental controls on
zooplankton vital rates, especially the timing and magnitude of reproduction, growth,
life-cycle progression, and mortality, determine species population dynamics,
seasonal and spatial distributions,...
Full Text:
, M.D. Ohman, W.T. Peterson, and J.A. Runge. 2013. Climate impacts on zooplankton population dynamics in
The 20-year US GLOBEC (Global Ocean Ecosystem Dynamics)
program examined zooplankton populations and their predators in four coastal
marine ecosystems. Program scientists learned that environmental controls on
zooplankton vital rates, especially the timing and magnitude of reproduction, growth,
life-cycle progression, and mortality, determine species population dynamics,
seasonal and spatial distributions,...
Full Text:
Fisheries
Science Center, National Oceanic and Atmospheric Administration, Newport, OR, USA.
JeffreyA
The 20-year US GLOBEC (Global Ocean Ecosystem Dynamics) program examined zooplankton populations and their predators in four coastal marine ecosystems. Program scientists learned that environmental controls on zooplankton vital rates, especially the timing and magnitude of reproduction, growth, life-cycle progression, and mortality, determine species population dynamics, seasonal and spatial distributions,...
The widespread use of engineered nanoparticles (ENPs) in industrial applications and consumer products makes their release to the environment inevitable. Understanding the aggregation behavior of ENPs is crucial to understanding their fate, transport and toxicology in aquatic systems. This study investigated the comparability of experimentally-determined and model-estimated attachment efficiencies for...
Understanding the aggregation behavior of engineered nanomaterials (ENMs) in aqueous environments is essential to understanding their fate, transport, and toxicity. Because naturally occurring colloids will likely be present at much higher concentrations than ENMs in environmental systems, heteroaggregation and attachment with these natural colloids could significantly influence ENM fate and...
The growing use of light-frame wood trusses in the
residential and commercial construction has generated the
need for general analysis procedures for predicting
deformations and ultimate load of truss-plate joints, which
are the basis for accurate evaluation of structural
performance and design of complete truss assemblies. This
dissertation was aimed...
In order to better predict the aggregation state of nanomaterials, the factors that influence aggregation must be understood. The combined effects of natural and engineered coatings have been shown to factor into nanoparticle aggregation behavior in preliminary research. In this study, aggregation behaviors of gold nanoparticles with two different engineered...
Fungi are the primary biological agents of wood deterioration and cause major economic losses of wood products globally. Wood in outdoor applications tends to remain wet for extended time periods, making it susceptible to fungal attack. Understanding the factors involved in fungal colonization of wood is important for developing improved...
Due to its frequent use in agriculture and its frequent detection in surface water,
atrazine was chosen as a model compound to study the treatment capability of a surface flow wetland used to remediate irrigation runoff at a container nursery near Portland, Oregon. Further evaluation of treatment of atrazine was...
Glioblastoma, which occurs in adults primarily between ages of 40 to 70 years and accounts for 15% of all brain tumors, is a devastating diagnosis with a median survival rate of less than a year. Invasiveness of glioblastoma cells significantly reduces the effectiveness of current treatments, highlighting the importance of...
The dominant controls on flow generation in steep, forested hillslopes are poorly understood. This dissertation examined the dominant flow processes operating at the hillslope scale, using a combined macroscale measurement and model development and analysis framework. Irrigation experiments at two steep forested hillslopes were conducted to isolate individual hillslope flow...
Throughout a large portion of our planet, malaria has been nearly eradicated or reduced to levels that are highly manageable, and many countries possess the means to effectively treat the disease. However, many areas of the world, such as Sub-Saharan Africa and Southeast Asia, are still heavily burdened by malaria....
Untreated wood is inherently hygroscopic and moisture content variations can have substantial effects on dimensional stability leading to the development of deep surface checks that further enhance moisture uptake and ultimately encourage deterioration. The horizontal exposure of wood crossties makes water repellency and dimensional stability particularly important in railroad applications....