A carefully calibrated primitive-equation model from 41°N to 48°N is used to study the poleward undercurrent off the US west coast. Chapter 2 describes poleward flow over the slope from Eulerian and Lagrangian perspectives. The model is robust, in the sense of several characteristics being qualitatively consistent with observational and...
Modifications of an ocean model are described, as the objective for which the model was used changed to study the kinematics and dynamics of an eastern-boundary poleward undercurrent.
The mathematical and physical connections between three different ways of quantifying linear predictability in geophysical fluid systems are studied in a series of analytical and numerical models. Normal modes, as they are traditionally formulated in the instabilities theories of geophysical fluid dynamics, characterize the asymptotic development of disturbances to stationary...
The long-term evolution of Gaussian eddies is studied in an equivalent barotropic model using both linear and nonlinear quasi-geostrophic theory in an attempt to understand westward propagating satellite altimetry tracked mesoscale eddies. By examining both individual eddies and a large basin seeded with eddies, it is shown that long term...
This thesis describes the results of a linear stability analysis conducted on a simulated wind-forced ocean front. The ocean surface boundary layer regulates exchanges between the ocean and atmosphere, and the presence of turbulence in the surface layer can greatly impact climate and ocean life. Past research has shown that...
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RogerM. Samelson Eric D. Skyllingstad
ABSTRACT
This thesis describes the results
An approach developed recently to study the dynamics of vorticity defects in homogeneous
shear flow extends naturally to the case of baroclinic, quasi-geostrophic
flow. It is shown that an inviscid geostrophic flow with uniform vertical shear may
be destabilized by introducing a `potential vorticity defect', an arbitrarily small but
sufficiently...
The dynamics of the growth of linear disturbances
to a chaotic basic state is analyzed in an asymptotic model of
weakly nonlinear, baroclinic wave-mean interaction. In this
model, an ordinary differential equation for the wave amplitude
is coupled to a partial differential equation for the zonal
flow correction. The leading...
We investigate, theoretically and experimentally, the problem of modeling depth-integrated (2DH) surf zone circulation on an alongshore-nonuniform natural beach, with waves approaching from an arbitrary angle. An approximate theoretical model is developed, which captures the important effect of advection in the alongshore dynamics, and shows that a nondimensional parameter Re[subscript]s...
A linearized model with two vertical modes has been developed to understand observed characteristics of monthly variability in the Equatorial Pacific from TOPEX/POSEIDON measurements of Sea Surface Height (SSH). The 2-mode model is obtained from an equatorial beta plane model that has been linearized about a geostrophically balanced mean flow...
We consider long planetary waves of annual period linearized about a steady, wind-driven subtropical (ST) gyre circulation. The circulation divides the gyre into an eastern zone (EZ) where only the surface layer is in steady motion and a western zone (WZ) where both the surface and the middle layer are...
The local predictability of the El Nin˜o–Southern Oscillation (ENSO) is examined by the analysis of the
evolution of small disturbances to an unstable 4.3-yr ENSO cycle in the Cane–Zebiak model forced by perpetual
July conditions. The 4.3-yr cycle represents the dominant near-recurrent behavior in this weakly chaotic regime,
so analysis...
A modeling study is undertaken to better understand the physics of katabatic flows. This study is divided into three topics; a comparison between a large eddy simulation (LES) and a mesoscale model of katabatic flows, a sensitivity study of katabatic flows to various physical parameters, and an investigation into the...
To examine the influence of forest management on wildlife immunity, the innate immune system of wild deer mice (Peromyscus maniculatus) inhabiting forest plots of different management intensities in the Oregon coast range was measured by bactericidal assay. Bactericidal activity was compared across three management levels, including 40-50 year old forest...
Full Text:
Immunity of Wild Deer Mice (Peromyscus maniculatus)?
Natalie M. Rogers1, Rhea Hanselmann1, and Anna E
To examine the influence of forest management on wildlife immunity, the innate immune system of wild deer mice (Peromyscus maniculatus) inhabiting forest plots of different management intensities in the Oregon coast range was measured by bactericidal assay. Bactericidal activity was compared across three management levels, including 40-50 year old forest...
The diffusivity dependence of internal boundary layers in solutions of the continuously stratified, diffusive
thermocline equations is revisited. If a solution exists that approaches a two-layer solution of the ideal thermocline
equations in the limit of small vertical diffusivity kᵥ, it must contain an internal boundary layer that collapses
to...
The influence of localized regions of intensified vertical mixing on the stratification and circulation in a large-scale ocean model is investigated with idealized numerical experiments. Numerical solutions are obtained of a closed-basin, single-hemisphere ocean model based on the planetary geostrophic equations. Mesoscale eddy effects are minimized, and vertical mixing at...
A simple theory is presented for steady geostrophic circulation of a stratified fluid in a rectangular basin with a circumpolar connection. The interior flow obeys the β-plane Sverdrup vorticity balance, and the circulation is closed by geostrophic boundary currents. The circulation is forced by surface thermal gradients and wind-driven Ekman...
A thermistor chain was towed 1400 km through the eastern North Pacific subtropical frontal zone in
January 1980. The observations resolve surface layer temperature features with horizontal wavelengths of
0.2-200 km and vertical scales of 10-70 m. The dominant features, which have horizontal wavelengths of
10-100 km, amplitudes of 0.2°-1.0°C,...
Linear disturbance growth is studied in a quasigeostrophic baroclinic channel model with several thousand degrees of freedom. Disturbances to an unstable, nonlinear wave-mean oscillation are analyzed, allowing the comparison of singular vectors and time-dependent normal modes (Floquet vectors). Singular vectors characterize the transient growth of linear disturbances in a specified...
The stability of a time-periodic baroclinic wave-mean oscillation in a high-dimensional two-layer quasigeostrophic spectral model is examined by computing a full set of time-dependent normal modes (Floquet vectors) for the oscillation. The model has 72 × 62 horizontal resolution and there are 8928 Floquet vectors in the complete set. The...
Observations of oppositely directed, monthly mean alongshore currents and wind stress over the continental margin off the Pacific coast of North America motivate the theoretical examination of mean flow generation by topographic lee-wave drag. We formulate a barotropic model for wind-forced shelf-slope flow over variable topography. Our central objective is...
We formulate analytically and solve numerically a semigeostrophic model for wind-driven thermocline upwelling at a coastal boundary. The model has a variable-density entraining mixed layer and two homogeneous interior layers. All variables are uniform alongshore. The wind stress and surface heating are constant. The system is started from rest, with...
Antarctic Ice Sheet mass balance and, hence, sea level change is affected by the floating extensions of outlet glaciers and ice streams that take up about 44% of the coastline (Drewry et al., 1982) and are referred to as "ice shelves". Ice sheet mass loss accelerates when these ice shelves...
A publication containing advice on a wide range of gardening topics, including composting, container gardens, fall/winter gardens, fertilizing, insect pests, plant diseases, planting guidelines, raised beds, site selection, slugs, soil improvement, tilling, warm-season crops, watering, and weeds. Includes regional tips for various parts of Oregon.
Interactions between surface winds and meanders in mid-latitude sea surface temperature
(SST) fronts with horizontal length scales of 100-1000 km are investigated
from satellite observations and numerical simulations. Observations from the Sea-
Winds scatterometer on the QuikSCAT satellite show that the magnitude, direction,
curl, and divergence of the surface wind...
The coastal ocean may experience periods of fluctuating
along-shelf wind direction, causing shifts between
upwelling and downwelling conditions with responses that
are not symmetric. We seek to understand these asymmetries
and their implications on the Eulerian and Lagrangian flows.
We use a two-dimensional (variations across-shelf and with
depth; uniformity along-shelf)...
Air–sea coupling during coastal upwelling was examined through idealized three-dimensional numerical simulations with a coupled atmosphere–ocean mesoscale model. Geometry, topography, and initial and
boundary conditions were chosen to be representative of summertime coastal conditions off the Oregon coast. Over the 72-h simulations, sea surface temperatures were reduced several degrees near...
Satellite observations of ice motion are combined with model estimates of low‐level winds and surface wind stress to provide evidence for atmospheric control of sea‐ice motion through Nares Strait, between Ellesmere Island and Greenland, during two periods in 2004. The results suggest that ice flux through the strait, and its...
The study analyzes atmospheric circulation around an idealized coastal cape during summertime upwelling-favorable wind conditions simulated by a mesoscale coupled ocean–atmosphere model. The domain resembles an eastern ocean boundary with a single cape protruding into the ocean in the center of a coastline. The model predicts the formation of an...
Satellite observations of wind stress and sea surface temperature (SST) are analyzed to investigate ocean–atmosphere interaction in the California Current System (CCS). As in regions of strong SST fronts elsewhere in the World Ocean, SST in the CCS region is positively correlated with surface wind stress when SST fronts are...
An analytical model of subtropical mode water is presented, based on ventilated thermocline
theory and on numerical solutions of a planetary geostrophic basin model. In ventilated
thermocline theory, the western pool is a region bounded on the east by subsurface
streamlines that outcrop at the western edge of the interior,...
Full Text:
. DEWAR
The Florida State University, Tallahassee, Florida
R. M. SAMELSON
College of Oceanic and
An analytical model of subtropical mode water is presented, based on ventilated thermocline
theory and on numerical solutions of a planetary geostrophic basin model. In ventilated
thermocline theory, the western pool is a region bounded on the east by subsurface
streamlines that outcrop at the western edge of the interior,...
Full Text:
of mode waters.J. Mar. Res., 40 suppl,
427–464.
Samelson, R. M., 1999. Note on a baroclinic
Two simplified ocean simulations are used to study circulation and transport within Nares Strait. The simulations are similar, except that one included a coupled sea ice model that effectively established a landfast ice cover throughout the simulation year. Comparison between the ocean-only and ocean-ice simulations reveals a systematic change in...
An analytical model of subtropical mode water is presented, based on ventilated thermocline theory and on numerical solutions of a planetary geostrophic basin model. In ventilated thermocline theory, the western pool is a region bounded on the east by subsurface streamlines that outcrop at the western edge of the interior,...
The vertical propagation of Coastal Trapped Waves (CTWs) due to subsurface ridges is explored with the help of linear numerical and analytical models. Results show that submerged ridges projecting from the shoreline can scatter a horizontally propagating single baroclinic mode Kelvin wave into both upward and downward propagating Kelvin wave...
The influence of mesoscale ocean eddies on near-surface ocean temperature, surface stress and phytoplankton communities is investigated by collocating numerous satellite measurements along with vertical profiles of oceanic temperature and salinity to the interiors of eddies identified and tracked in altimetric sea surface height maps.
The surface currents associated with...
This thesis examines the mechanisms that couple the monthly-averaged
atmospheric boundary layer (ABL) to open-ocean sea surface temperature (SST)
perturbations on scales of 50-500 km. The observed positive correlation between
surface wind speed anomalies and SST anomalies is successfully simulated using
the Weather Research and Forecasting (WRF) model.
In numerical...
The focus of this dissertation is the analysis of submesoscale and finescale features measured at oceanic fronts and the role they play in the transport of heat and salt. Two different geographical areas were used to analyze this transport: one, an area on the western side of the North Atlantic...
Internal waves and tides are a dominant source of current variability, and they are intermittent and hard to predict. Internal waves can have significant variability in alongshore structure. However, previous studies on internal waves have focused primarily on their cross-shore structure and propagation. For example, while alongshore-propagating superinertial internal tides...
Two idealized, three-dimensional, analytical models of middepth meridional overturning in a basin with a Southern Hemisphere circumpolar connection are described. In the first, the overturning circulation can be understood as a “pump and valve” system, in which the wind forcing at the latitudes of the circumpolar connection is the pump...
A recently proposed reduced-gravity model of the warm-water branch of the middepth meridional overturning circulation in a rectangular basin with a circumpolar connection is extended to include time dependence. The model describes the balance between gain of warm water through northward Ekman advection across the circumpolar current, loss of warm...
The vertical structure of coastal-trapped disturbances in several idealized models of a stably stratified lower atmosphere is examined. The vertical structure and phase speeds of the trapped modes depend on the resting stratification and the height of the orographic step. The presence of a stable layer above the boundary layer...
A reduced-gravity model is presented of the warm-water branch of the middepth meridional overturning circulation in a rectangular basin with a circumpolar connection. The model describes the balance between production of warm water by Ekman advection across the circumpolar current, dissipation of warm water by eddy fluxes southward across the...
The growth of linear disturbances to stable and unstable time-periodic basic states is analyzed in an asymptotic
model of weakly nonlinear, baroclinic wave–mean interaction. In this model, an ordinary differential equation
for the wave amplitude is coupled to a partial differential equation for the zonal-flow correction. Floquet vectors,
the eigenmodes...
The dynamical response of the marine atmospheric boundary layer (MABL) to mesoscale sea surface temperature (SST) perturbations is investigated over the Agulhas Return Current during winter from a 1-month, high-resolution, three-dimensional simulation using the Weather Research and Forecasting (WRF) mesoscale model. A steady lower boundary condition for July 2002 is...
Ten years of sea-surface height (SSH) fields constructed from the merged TOPEX/Poseidon (T/P) and ERS-1/2 altimeter datasets are analyzed to investigate mesoscale variability in the global ocean. The higher resolution of the merged dataset reveals that more than 50% of the variability over much of the World Ocean is accounted...
Three mechanisms for self-induced Ekman pumping in the interiors of mesoscale ocean eddies are investigated.
The first arises from the surface stress that occurs because of differences between surface wind and
ocean velocities, resulting in Ekman upwelling and downwelling in the cores of anticyclones and cyclones,
respectively. The second mechanism...
Previously unaddressed aspects of how equatorial currents affect long Rossby wave phase speeds are investigated using solutions of the shallow-water equations linearized about quasi-realistic currents. Modification of the background potential vorticity (PV) gradient by curvature in the narrow equatorial currents is shown to play a role comparable to the Doppler...
The effects of wind forcing on coastal ocean circulation are studied using a
numerical modeling approach. The first region of interest is on the North Carolina
shelf, where the Coastal Ocean Processes (CoOP) Inner Shelf Study (ISS) took place
during August - November 1994. ISS observations are used to initialize,...
Fair value accounting has become a very popular and controversial topic in light of the 2008-2009 liquidity crisis in the United States. Fair value, also called mark-to-market, implies that assets and liabilities get measured and reported in firms‘ financial statements at market value as opposed to historical value. This study...
The wind speed response to mesoscale SST variability is investigated over the Agulhas Return Current region of the Southern Ocean using the Weather Research and Forecasting (WRF) Model and the U.S. Navy Coupled Ocean–Atmosphere Mesoscale Prediction System (COAMPS) atmospheric model. The SST-induced wind response is assessed from eight simulations with...
Data from an array of bottom pressure gauges and a string of current meters in the vicinity of 47°N,
139°W, are used to examine the deep-ocean variability forced by ocean surface wind stress curl from
August 1987 to June 1988. Bottom geostrophic currents are computed from the pressure gauge array,...
The Oregon Coastal Transition Zone (OCTZ) extends several hundred
kilometers offshore where shelf flows interact with the northern California Current. A
primitive-equation numerical ocean model is used to study the upwelling circulation in this
region from 1 May to 1 November 2001. This OCTZ model obtains initial and boundary
conditions...
Summertime low clouds are common in the Pacific Northwest (PNW), but spatiotemporal patterns have not been characterized. We show the first maps of low cloudiness for the western PNW and North Pacific Ocean using a 22‐year satellite‐derived record of monthly mean low cloudiness frequency for May through September and supplemented...
Meteorological conditions during an intensive oceanographic observational program
in May through August 2001 along the central Oregon coast are described and related to
larger-scale and longer-term conditions. Southward wind stresses of 0.05-0.1 N m⁻²
occurred roughly 75% of the time, with a sustained period of dominantly southward stress
from mid-June...
In the continuing effort to reduce time spent in the product development cycle many industries
have realized the benefits of rapid prototyping. Within a few hours a design engineer can turn a
computer model into an actual three-dimensional object allowing customers, engineers and
marketing agents to evaluate a product early...
Nitrosomonas europaea (ATCC19718) participates in the biological removal of nitrogen from wastewater by oxidizing ammonia to nitrite, the first step in nitrification. This bacterium is sensitive to heavy metals (Zn²⁺, Cd²⁺, Cu²⁺, and Hg²⁺) and cyanide, compounds commonly encountered in wastewater treatment plants. Therefore, we characterized physiological and transcriptional responses...
Photobiological hydrogen production from live cells of the cyanobacterium Synechocystis sp. PCC 6803 encapsulated in silica gel was investigated. Hydrogen is a dense energy carrier with potential to reduce dependence on fossil fuels, provided a renewable and sustainable means of production can be achieved. Under certain conditions, Synechocystis sp. PCC...
The thermophilic cyanobacterium Thermosynechococcus elongatus was examined for the ability to sequester CO₂ while producing hydrogen (H₂), polyhydroxybutyrate (PHB), lipids, and glycogen. H₂ was produced at a maximum rate of 188 nmol H₂ mg Chl a⁻¹ hr⁻¹. Hydrogen production occurred in the presence of methyl viologen but the cells were...
This study examined the role of acid- sensing ion channels (ASICs) in interneuron synaptic modulation. ASICS are ultra fine discriminators of acidic conditions in the neuronal microenvironment. Each ASIC subunit isoform has innate, subtly different electrophysiological properties and tissue distributions. Structurally, ASICs may form homo- or heteromeric channels, yielding combinatorial...
Oregon, much like the nation, has historically had a paradoxical relationship to migration. Oregon is famous for the Lewis and Clark expedition and the Oregon Trail. It is, and always has been, greatly affected and inspired by interstate migration yet each successive generation has been less than welcoming to further...
A history of fire suppression, growth in the wildland-urban interface, and changing climate conditions, have created a fire regime in central Oregon that is growing in severity and intensity, putting more people and structures at risk and requiring a greater percentage of state and federal agency budgets to manage fires....
An evaluation was made of factors contributing to the service
failure of a 12 inch diameter cast iron water pipe in Pendleton, Oregon.
The quality of the pipe was found to be acceptable when compared to the
acceptance limits established by the American National Standards
Institute, Inc. However it exhibited...
Decades of experimental work has illustrated the high degree to which the partitioning of most elements is dependent on phase composition, temperature and pressure. In order to quantitatively describe clinopyroxene partitioning it is required to derive expressions using theoretical constraints calibrated with experimental data.
The experimental database available for such...
A Cell Phone Audio Controlled Point of Sale system was designed and built for an undergraduate electrical and computer engineering senior design project. The system was designed to enable a user to transfer data from any cell phone to a point of sale device using audio tones. The project involved...
Due to the current cultural paradigm that incorporates the desire to be environmentally friendly and mitigate rising fuel costs, arguments about the cost of public transit systems, ridership rates, and methods to increase use are frequent topics of public policy concern. In response to these cultural and economic concerns, the...
A wireless power transfer system using inductive coupling was designed and implemented as part of a three-member project team. The system uses coupled magnetic fields at a frequency of 606kHz to transfer electromagnetic energy from a charging base to the batteries of portable devices. It succeeded in transmitting power to...
To understand the forces exerted on structures during tsunamis, model cities are subjected to human-generated tsunamis. The study of vertical evacuation, wherein individuals could take refuge in the upper levels of strong buildings, has resulted in a growing need for a low cost wireless acceleration data logger. Such a device...
This study uses the Health Impact Assessment approach to determine the health impacts of allowing accessory dwelling units in Benton County, Oregon. A literature review presents the health benefits of accessory dwelling units in urban areas and identifies the potential negative health effects in rural areas. Five accessory dwelling units...
As the Tekbots program expands into senior and graduate level classes at Oregon State University, so does the need arise for more complex learning platforms. These complex hardware platforms cannot be adequately tested in a manufacturing environment as we have done previously. Also, due to their complexity, these platforms require...
Retention of engineering students is a problem for many universities, especially during the first year. The problem of introducing students to engineering while increasing retention rates has recently been addressed by many different universities. Implementing novel lab structures, adjusting the lecture to incorporate more effective teaching techniques, and using orientation...
The passage of Measure 37 in 2004 was met with a great deal of controversy as a number of voters claimed the implications of the Measure did not represent their intentions for supporting the legislation. Namely, significant opposition was aimed towards the Measure 37 claim which offered landowners financial compensation...
Landforms are natural features on the Earth’s surface that both reflect and shape geophysical and ecological process. The result is a defining part of landscapes that so often impact on human perception and interactions with environment. Blascyznki (1997) defines landforms as, “specific geomorphic features on the surface of the Earth,...
Regional ocean circulation along the Oregon coast is studied numerically for forcing fields derived from year 2005 and climatological-mean conditions. The primary object is to study directly the Lagrangian pathways by which fluid arrives in the Oregon upwelling zone. Roughly half of the upwelling fluid is found to arrive in...
For data following a balanced mixed Anova model, the standard Anova method typically leads to exact F tests of the usual hypotheses about fixed effects. However, for most unbalanced designs with most hypotheses, the Anova method does not produce exact tests, and approximate methods are needed. One approach to approximate...
Counselor education programs traditionally have student counselors role-play therapy sessions to enhance skills in rapport building, aligning with a theoretical orientation, and other essential communication skills. Students, however, are often left to determine their own choice of words when engaging in these practice sessions, and consequently, experience uncertainty regarding how...
Household recycling is an important means by which social costs of solid waste
disposal may be reduced. These costs include energy and resource costs of collection
and disposal as well as environmental costs from emissions from landfills, incinerators,
and collection vehicles. In this thesis, a household production model is used...
This thesis considers the problem of estimating the linear
parameters of generalized linear models (GLM), especially binomial
and Poisson regression models, when the explanatory variable is
subject to measurement error. In this situation, the dependence of
the response variable on the observed explanatory variable cannot
typically be modeled as a...
The U.S Pacific Northwest contains a wide variety of ecosystems, all subject to relatively dry summers and wet winters. As has been shown with paleoclimatic and paleoecological data, the region is vulnerable to changes in climate. We assessed the sensitivities of vegetation distributions, carbon stocks, and fire regimes to 21st...
The main purpose of this project is to describe the hydrologic characteristics, with and without
regulation by dams, of the Coast and Middle Forks of the Willamette River, including the
floodplain, from the confluence to approximately eight miles upstream. The research is intended
to assess the future potential of the...
This study explores the extent to which the United States has conformed to the tenets of classical liberalism and/or civic republicanism with regard to private property and takings law. Mainstream scholarship suggests that classical liberal theory has played a dominant role in American property law since the founding. In the...
Djang et al. [1998] introduced a new model of types for declarative visual programming languages (VPLs). Implicit static typing is used in their type model, in order to eliminate the programming mechanisms associated with type declarations, provide immediate visual feedback with respect to type errors and guarantee type safe programs....
The olfactory bulb contains the first synaptic relay in the olfactory pathway, the sensory system in which odorants are detected enabling these chemical stimuli to be transformed into electrical signals and, ultimately, the perception of odor. Acid-sensing ion channels (ASICs), a family of proton-gated cation channels, are widely expressed in...
Interaction between mixed layer baroclinic eddies and small-scale turbulence is studied using a nonhydrostatic large-eddy simulation (LES) model. Free, unforced flow evolution is considered, for a standard initialization consisting of an 80-m-deep mixed layer with a superposed warm filament and two frontal interfaces in geostrophic balance, on a model domain...
Estimates of three components of an uncertainty budget for a coastal ocean model in a wind-forced regime
are made based on numerical simulations. The budget components behave differently in the shelf regime,
inshore of the 200-m isobath, and the slope-interior regime, between the 200-m isobath and a fixed longitude
(1268W)...
An unstable, nonlinear baroclinic wave-mean oscillation is found in a strongly supercritical quasigeostrophic f-plane numerical channel model with 3840 Fourier components. The growth of linear disturbances to this time-periodic oscillation is analyzed by computing time-dependent normal modes (Floquet vectors). Two different Newton–Picard methods are used to compute the unstable solution,...
The intraseasonal variability of turbulent surface heat fluxes over the Gulf Stream extension and subtropical mode water regions of the North Atlantic, and long-term trends in these fluxes, are explored using NCEP–NCAR reanalysis. Wintertime sensible and latent heat fluxes from these surface waters are characterized by episodic high flux events...
The predictability of coastal ocean circulation over the central Oregon shelf, a region of strong wind-driven
currents and variable topography, is studied using ensembles of 50-day primitive equation ocean model
simulations with realistic topography, simplified lateral boundary conditions, and forcing from both idealized
and observed wind time series representative of...
This paper presents a methodology for performing complex wavenumber ray tracing in which both wave trajectory and amplitude are calculated. This ray-tracing framework is first derived using a scaling in which the imaginary wavenumber component is assumed to be much smaller than the real wavenumber component. The approach, based on...
The purpose of this research was to examine factors associated
with the social climate of single-sex and coeducational residence
halls, fraternities, sororities, and cooperatives on the Oregon State
University campus.
The primary sources of data for this study were student
responses to the ten subscales of the URES Form R,...
Biological plant invasions are diminishing the ecological integrity and function of ecosystems worldwide. A primary example of this is in the Great Basin of the United States, where invasive annual grasses, like cheatgrass (Bromus tectorum L.) and medusahead (Taeniatherum caput-medusae L. Nevski), are dominating many sagebrush-steppe ecosystems. In these invaded...
Many methods in use today for the isolation, purification, and
identification of the staphylococcal enterotoxins involve lengthy
steps with significant loss of enterotoxin, are subject to interference
from contaminating sample components, and lack sufficient specificity.
Culture extracts of enterotoxin producing Staphylococcus
aureus strains (enterotoxins A-E), crude enterotoxin preparations
(enterotoxins A-E),...
Photobiological hydrogen production -- the use of photosynthesis to split water into hydrogen and oxygen -- presents an opportunity for efficient and large-scale solar biofuel development. One of the major challenges in this area is competition for reductant between the hydrogen-evolving hydrogenase enzyme and other metabolic pathways. In this work...