Cyanobacteria inhabit nearly every ecosystem on earth, play a vital role in nutrient cycling, and are
useful as model organisms for fundamental research in photosynthesis and carbon and nitrogen fixation.
In addition, they are important for several established biotechnologies for producing food additives,
nutritional and pharmaceutical compounds, and pigments, as...
The discovery on Mars of recurring slope lineae (RSL), thought to represent seasonal brines, has sparked interest in analogous environments on Earth. We report on new studies of Don Juan Pond (DJP), which exists at the upper limit of ephemeral water in the McMurdo Dry Valleys (MDV) of Antarctica, and...
PN-specific, absolute, and Chl a-specific nitrate uptake rates were measured during two upwelling seasons and one winter off Oregon. Although PN-specific and absolute uptake rates showed no dependence on nitrate concentration, Michaelis-Menten kinetics applied when the uptake rates were normalized to Chl a. Chl a-specific nitrate uptake rates were saturated...
Chlorophyll a concentrations were measured as a function of depth from 28 to 48°N along 152°W in March 1991 with Whatman GF/F and 0.2‐µm Nuclepore filters. Surface Chl a concentrations measured with 0.2‐µm Nuclepore filters were up to fourfold higher than those measured with Whatman GF/F filters. The largest difference...
Ammonium uptake and regeneration rates were measured in time course experiments with 15N as a tracer. Both ammonium uptake and regeneration rates measured over 12 to 18 h remained essentially constant. However, as the length of the incubations increased the amount of usable data decreased dramatically due to substrate depletion...
In shallow water, any two waves of the same frequency are shown to produce complex patterns of
drift velocity above the sea bed. If the longshore components λ₁, λ₂ of the wave numbers of the two
waves are different, these steady flow patterns exhibit a longshore periodicity of wave number...
Black Brant (Branta bernicla nigricans) distribution was monitored and eelgrass beds (Zostera marina) were mapped during the spring migration of 1976. Brant used eelgrass areas significantly, and human disturbance and tide height were important factors influencing Brant distribution and activity.
***************************************************************************
DavidJ. Wetzel (current address unknown)
CITATION: Wetzel, D. J. 1996. Brant use of Yaquina Estuary
Numerous monitoring efforts are underway to improve understanding of ocean acidification and its impacts on coastal environments, but there is a need to develop a coordinated approach that facilitates spatial and temporal comparisons of drivers and responses on a regional scale. Toward that goal, the California Current Acidification Network (C-CAN)...
We estimate the impact of strict and multiple use protected areas on forest disturbance in European Russia between 1985 and 2010. We construct a spatial panel dataset that includes five periods of change. We match protected areas to control observations and compare coefficients from fixed versus random effects models. We...
We give a new approach to coding sequence (CDS) density
estimation in genomic analysis based on the topological pressure, which
we develop from a well known concept in ergodic theory. Topological
pressure measures the ‘weighted information content’ of a finite word,
and incorporates 64 parameters which can be interpreted as...
We examine cumulative changes in investor sentiment and find that these changes relate to extended periods of increasing overvaluation, followed by price corrections. The relation between sentiment and returns is path dependent — short-term increases in sentiment precede strong positive returns, while prolonged periods of increasing sentiment precede negative returns....
The provision of many ecosystem services depends on the spatial pattern of land use across multiple landowners. Even holding land use constant, ecosystem service provision may change through time due to climate change. This paper develops an auction mechanism that implements an optimal solution for providing ecosystem services through time...
Estimating nonmarket benefits for erosion protection can help inform better decision making and policies for communities to adapt to climate change. We estimate private values for a coastal protection option in an empirical setting subject to irreversible loss from coastal erosion and a land-use policy that provides identifying variation in...
We examined short-term (24–72 h) responses of naturally occurringmarine N2 fixing microorganisms (termed diazotrophs) to abrupt increases in the partial pressure of carbon dioxide (pCO2) in seawater during nine incubation experiments conducted between May 2010 and September 2012 at Station ALOHA (A Long-term Oligotrophic Habitat Assessment) (22°45′N, 158°W) in the...
We develop a classical density functional for water which combines the White Bear fundamental-measure theory (FMT) functional for the hard sphere fluid with attractive interactions based on the statistical associating fluid theory variable range (SAFT-VR). This functional reproduces the properties of water at both long and short length scales over...
We explore the optimal time path of carbon sequestration and carbon abatement in stabilizing
CO₂ levels under uncertainty of climate impacts. Using a two-period sequential decision making
model, we analytically derive optimal rates for the two control variables, abatement and
sequestration rates. Uncertainty is assumed to affect the desired future...
Hot spot–mid-ocean ridge interactions cause many of the largest structural and chemical anomalies in Earth’s ocean basins. Correlated geophysical and geochemical anomalies are widely explained by mantle plumes that deliver hot and compositionally distinct material toward and along mid-ocean ridges. Compositional anomalies are seen in trace element and isotope ratios,...
Acoustic scattering layers are ubiquitous, horizontally extensive aggregations of both vertebrate and invertebrate organisms that play key roles in oceanic ecosystems. However, currently there are no conventions or widely adaptable automatic methods for identifying these often dynamic, spatially complex features, so it is difficult to consistently and efficiently describe and...
Deforestation and conversion of native habitats continues to be the leading driver of biodiversity and ecosystem service loss. A number of conservation policies and programs are implemented—from protected areas to payments for ecosystem services (PES)—to deter these losses. Currently, empirical evidence on whether these approaches stop or slow land cover...
Rawinsonde observations taken during the National Hail Research Experiment are analyzed by multiple-linear regression techniques to study the influence of environmental factors on hailstorm severity. The latter is inferred from integrated radar returns. The roles of mixed-layer flow and thermodynamic properties as well as upper tropospheric kinematic properties are emphasized....
Case history analysis, cross spectra and multiple regression analysis have been used in a study of low-pass filtered sea level records from the Pacific mainland coast of Mexico in 1971 and 1973–75. During the summer-fall season (May–October), sea level variability is characterized by strong alongshore coherence and nondispersive, poleward phase...
In their recent Canadian Journal of Forest Research Comment 368 article, Wilson and Oliver (2000) developed an equation for predicting the average ratio of height to diameter at breast height for the largest 250 trees/ha (H/DL250) in unthinned stands as a function of initial density and dominant height of the...
Phylogenetic relationships of the Antiperyphanes Complex of the genus Bembidion are inferred using DNA
sequences from seven genes (two nuclear ribosomal, four nuclear protein coding, and one mitochondrial
protein coding). Redefined subgenera within the complex are each well-supported as monophyletic. Most
striking was the discovery that a small set of...
Thoreau's experiment at Walden Pond reveals two potentially contradictory desires, one of which can be linked to agrarian reform, and the other to ecological knowledge. Thoreau conceived his Walden project in a cultural milieu in which agrarian reform was receiving incrasing attention, and the Walden experiments was, in important ways,...
The concept of sustainable resource management can be applied at multiple scales.
Monitoring is an essential component of sustainable natural resource management
schemes, and as we begin to confront the need to manage natural resources at the
global scale, the importance of monitoring at the global scale is also growing....
To investigate CO₂ chemistry in ocean water with greater time-space resolutions, we systems, which have state-of-the-art precision but an order of magnitude or better analysis, for carbon dioxide partial pressures (Pco₂) and total carbon dioxide Pco₂ system was based on equilibration of a CO₂-free carrier gas stream with seawater sample...
Because iso- and anisohydric species differ in stomatal regulation
of the rate and magnitude of fluctuations in shoot
water potential, they may be expected to show differences in
the plasticity of their shoot water relations components, but
explicit comparisons of this nature have rarely been made.
We subjected excised shoots...
During the summer of 2012, we used laser diffractometry to investigate the temporal and vertical variability of the particle size spectrum (1.25–100 µm in equivalent diameter) in the euphotic zone of the North Pacific Subtropical Gyre. Particles measured with this optical method accounted for ∼40% of the particulate carbon stocks...
Many ecosystem services are public goods whose provision depends on the spatial pattern of land use. The pattern of land use is often determined by the decisions of multiple private landowners. Increasing the provision of ecosystem services, while beneficial for society as a whole, may be costly to private landowners....
Within the Australian-Antarctic Discordance (AAD), a boundary exists between isotopically defined “Pacific-type” and “Indian-type” mid-ocean ridge basalt (MORB) erupted along the Southeast Indian Ridge (SEIR). This boundary has migrated westward beneath the easternmost AAD spreading segment at a minimum rate of 25 mm/yr since 4 Ma; however, its long-term history...
We compared uropathogen antibiotic susceptibility across age groups of ambulatory
pediatric patients. For Escherichia coli (n=5,099) and other Gram-negative rods (n=626), significant
differences (p<0.05) existed across age groups for ampicillin, cefazolin, and
trimethoprim/sulfamethoxazole susceptibility. In E. coli, differences in
trimethoprim/sulfamethoxazole susceptibility varied from 79% in children under 2 to 88%...
Estimating the stock proportions of mixed-stock fishery samples by means of genetic stock identification has played an important role in the management of salmon fisheries. In addition, stock identification of individual fish has applications for population studies, forensic cases, and management issues. We examined 11 microsatellite DNA loci in 84...
Several approaches for travel time data collection based on the reading of time-stamped media access control addresses from Bluetooth-enabled devices have been reported in the literature recently. This new approach offers a number of advantages over more conventional methods, including lower costs of hardware and software, the volume of data...
Leaf hydraulics, gas exchange and carbon storage in Pinus edulis and Juniperus monosperma, two tree species on opposite ends of the isohydry–anisohydry spectrum, were analyzed to examine relationships between hydraulic function and carbohydrate dynamics. Leaf hydraulic vulnerability, leaf water potential (Wl), leaf hydraulic conductance (Kleaf), photosynthesis (A), stomatal conductance (gs)...
Early adulthood is a time of transition when large segments of the population embrace new roles and show decreases in behaviors and problems thought to underlie suicide risk. Still, other segments show emergent or worsening psychopathology per-haps exacerbated by age-related disconnection from prior relational and institutional supports. Suicide prevention efforts...
The Pacific lamprey (Entosphenus tridentatus) is in decline in the Columbia River Basin, and translocating adult lamprey to bypass difficult migration corridors has been implemented since 2000. We describe and report results from two current translocation programs, provide context for use of translocation, and discuss potential benefits, risks, and uncertainties....
Digestion of milk proteins in the premature infant stomach releases functional peptides; however, which peptides are present has not been reported. Premature infants are often fed a combination of human milk and bovine milk fortifiers, but the variety of functional peptides released from both human and bovine milk proteins remains...
Both nanoparticulate (nZnO and nTiO(2)) and organic chemical ultraviolet (UV) filters are active ingredients in sunscreen and protect against skin cancer, but limited research exists on the environmental effects of sunscreen release into aquatic systems. To examine the trade-offs of incorporating nano particles (NPs) into sunscreens over the past two...
We used microsatellite DNA data and genetic stock identification methods to delineate the temporal and spatial distributions of juvenile Chinook Salmon Oncorhynchus tshawytscha occupying coastal habitats extending from central Oregon to northern Washington. Juveniles were collected in trawl surveys conducted during spring, summer, and autumn over 15 years. Distributions (mean...
Greater sage-grouse (Centrocercus urophasianus; sage-grouse) are highly susceptible to infection with West Nile virus (WNV), with substantial mortality reported in wild populations and in experimentally infected birds. Although sage-grouse are hunted throughout much of their range, they have also recently been considered for protection under the Endangered Species Act. We...
Melt inclusions trapped in phenocryst phases are important primarily due to their potential of preserving a significant proportion of the diversity of magma composition prior to modification of the parent magma array during transport through the crust. The goal of this investigation was to evaluate the impact of formational and...
Background: Academic medical centers are examining relationships with the pharmaceutical industry
and making changes to limit interactions. Most doctors, however, practice outside of academic institutions
and see pharmaceutical detailers and accept drug samples and gifts. Little guidance for practicing
physicians exists about transforming practices to become pharma-free. Consideration must be...
Crested wheatgrass (Agropyron cristatum [L] Gaertm) has been seeded on more than 5 million hectares in western North America because it establishes more readily than native bunchgrasses. Currently, there is substantial interest in reestablishing native species in sagebrush steppe, but efforts to reintroduce native grasses into crested wheatgrass stands have...
In order to develop dielectric ceramics with temperature-stable permittivity characteristics, perovskite BaTiO[subscript 3]-Bi(Zn[subscript 1/2]Ti[subscript 1/2])O-[subscript 3]-NaNbO[subscript 3] ceramic solid solutions were investigated with a particular focus on effects of BaTiO[subscript 3] and NaNbO[subscript 3] contents on the dielectric properties of ternary compounds. Keeping the ratios of the other two constituents...
We present a modification to our recently published statistical associating fluid theory-based classical
density functional theory for water. We have recently developed and tested a functional for the
averaged radial distribution function at contact of the hard-sphere fluid that is dramatically more accurate
at interfaces than earlier approximations. We now...
Advancing our ability to use invasive plants for producing commodities is central to the agricultural industry. Our objective was
to evaluate Russian knapweed (Acroptilon repens [L.] DC.) as a winter feed supplement for ruminant livestock. In Experiment
1, we utilized three ruminally cannulated steers in a completely randomized design to...
Invasive species in riparian forests are unique as their effects can transcend ecosystem boundaries via stream-riparian linkages. The green alder sawfly (Monsoma pulveratum) is an invasive wasp whose larvae are defoliating riparian thin-leaf alder (Alnus tenuifolia) stands across southcentral Alaska. To test the hypothesis that riparian defoliation by this invasive...
The atrypid brachiopod Strophatrypa skaflestadi gen. et sp. nov. occurs in unnamed upper Silurian strata exposed near the town of Hoonah on northeast Chichagof Island, Southeast Alaska. The new genus represents the first strophic atrypoid with many characters otherwise similar to those of the Atrypidae. Although this genus is known...
More than 40 years have passed since Shafer (1969) challenged the existence of the “average
camper.” Recognizing that participants in recreation activities are heterogeneous in their
commitments and interests, researchers have emphasized the importance of differentiating
users into meaningful homogeneous subgroups. In his seminal article, Bryan (1977) coined
the concept...