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Total mercury (Hg) deposition and input/output relationships were investigated in an 11-ha deciduous forested catchment in northern Vermont as part of ongoing evaluations of rig cycling and transport in the Lake Champlain basin. Atmospheric Hg deposition (precipitation + modeled vapor phase downward flux) was 425 mg ha-1 during the one-year...

Reflectance spectra in the 1- to 2.5-micrometer wavelength region of the surface of Europa obtained by Galileo's Near Infrared Mapping Spectrometer exhibit distorted water absorption bands that indicate the presence of hydrated minerals. The laboratory spectra of hydrated salt minerals such as magnesium sulfates and sodium carbonates and mixtures of...

A previously unknown solid phase of H2O has been identified by its peculiar growth patterns, distinct pressure-temperature melting relations, and vibrational Raman spectra. Morphologies of ice crystals and their pressure-temperature melting relations were directly observed in a hydrothermal diamond-anvil cell for H2O bulk densities between 1203 and 1257 kilograms per...

As a component of a lakewide mass balance study for Lake Michigan, we measured total mercury (Hg(T)) concentrations and fluxes in 11 selected tributaries. Unfiltered Hg(T) concentrations ranged from 0.56 ng l-61 at the Pete Marquette River to 182 ng l-1 at the Fox River. Highest mean Hg(T) concentrations were...

[No abstract available]...

Passive sampling of dissolved hydrophobic contaminants with lipid (triolein)-containing semipermeable membrane devices (SPMDs) has been gaining acceptance for environmental monitoring. Understanding of the accumulation process has employed a simple polymer film-control model of uptake by the polymer-enclosed lipid, while aqueous film control has been only briefly discussed. A more complete...

This study was conducted to determine landscape and fine-scale vegetative variables associated with breeding Loggerhead Shrikes (Lanius ludovicianus) on Fort Riley Military Reservation, Kansas. Because Fort Riley is an Army training site, the influences of training disturbance to the vegetation, and range management practices on bird habitat patterns were also...

Nucleic acid-based assays have shown promise for diagnosing Renibacterium salmoninarum in tissues and body fluids of salmonids. DeVelopment of a nested polymerase chain reaction (PCR) method to detect a 320 bp DNA segment of the gene encoding the p57 protein of R. salmoninarum is described. Whereas a conventional PCR for...

Petrofacies analysis is defined as the characterization and classification of pore types and fluid saturations as revealed by petrophysical measurements of a reservoir. The word "petrofacies" makes an explicit link between petroleum engineers' concerns with pore characteristics as arbiters of production performance and the facies paradigm of geologists as a...

No abstract available. ...

We compared reproductive and physiological responses of captive female northern bobwhite (Colinus virginianus) and scaled quail (Callipepla squamata) under control and water deprivation conditions. Scaled quail required less food and water to reproduce successfully under control conditions than northern bobwhite. Additionally, in scaled quail, serum osmolality levels and kidney mass...

The status of the White-faced Ibis (Plegadis chihi) in the Great Basin is of concern because of its small population size and the limited and dynamic nature of its breeding habitat. We analyzed existing annual survey data for the White-faced Ibis breeding in the Great Basin and surrounding area for...

Arthropod cuticles consist predominantly of chitin cross-linked with proteins. While there is some experimental evidence that this chitin-protein complex may resist decay, the chemical changes that occur during degradation have not been investigated in detail. The stomatopod crustacean Neogonodactylus oerstedii was decayed in the laboratory under anoxic conditions. A combination...

A discrete-time wave propagation formulation of the seismic response of tall buildings is introduced. The building is modeled as a layered medium, similar to a layered soil medium, and is subjected to vertically propagating seismic shear waves. Soil layers and the bedrock under the foundation are incorporated in the formulation...

Over the last 25 yr, considerable debate has continued about the future supply of fossil fuel. On one side are those who believe we are rapidly depleting resources and that the resulting shortages will have a profound impact on society. On the other side are those who see no impending...

For a decade, the U.S. Geological Survey has used the Parkfield Earthquake Prediction Experiment scenario document to estimate the probability that earthquakes observed on the San Andreas fault near Parkfield will turn out to be foreshocks followed by the expected magnitude 6 mainshocks....

Models of the effects of atmospheric N deposition in forested watersheds have not adequately accounted for the effects of aquatic and near-stream processes on the concentrations and loads of NO3/- in surface waters. This study compared the relative effects of aquatic and near-stream processes with those from the terrestrial ecosystem...

Biological soil crusts, consisting of cyanobacteria, green algae, lichens, and mosses, are important in stabilizing soils in semi-arid and arid lands. Integrity of these crusts is compromised by compressional disturbances such as foot, vehicle, or livestock traffic. Using a portable wind tunnel, we found threshold friction velocities (TFVs) of undisturbed...

Test well BFT-2055 was drilled through the entire thickness of Coastal Plain sediments beneath central Hilton Head Island, South Carolina, and terminated in bedrock at a depth of 3833 feet. The well was drilled to evaluate the hydraulic properties of the Cretaceous formations beneath Hilton Head Island as a potential...

Abnormal pressures, pressures above or below hydrostatic pressures, occur on all continents in a wide range of geological conditions. According to a survey of published literature on abnormal pressures, compaction disequilibrium and hydrocarbon generation are the two most commonly cited causes of abnormally high pressure in petroleum provinces. In young...

We used the Mahalanobis distance statistic and a raster geographic information system (GIS) to model potential black bear (Ursus americanus) denning habitat in the Ouachita Mountains of Arkansas. The Mahalanobis distance statistic was used to represent the standard squared distance between sample variates in the GIS database (forest cover type,...

Degradation products of the 2,3,6-/3,4,5-trimethyl substituted analog of isorenieratene were characterized in Belarussian petroleums. Devonian oils of low maturity were found to contain high concentrations (e.g., 35 mg/g) of C40 diaryl isoprenoids (2,3,6-/3,4,5-trimethyl substitution) along with an abundance of maturation-related compounds. A maturation scheme for diaryl carotenoid (2,3,6-/3,4,5-trimethyl substitution) precursors...

The Cape Sable seaside-sparrow (Ammodramus maritimus mirabilis) has disappeared from its only known breeding areas episodically since its discovery early this century. Systematic surveys across its range in the southern Everglades find the sparrow's range to be fragmented into six subpopulations. The sparrow population decreased by 58% between 1992 and...

We acquired high-resolution seismic-refraction data on the ground surface in selected areas of the San Fernando Valley (SFV) to help explain the earthquake damage patterns and the variation in ground motion caused by the 17 January 1994 magnitude 6.7 Northridge earthquake. We used these data to determine the compressional- and...

Coals are both sources and reservoirs of large amounts of gas that has received increasing attention in recent years as a largely untapped potential energy resource. Coal mining operations, such as ventilation of coalbed gas from underground mines, release coalbed CH4 into the atmosphere, an important greehouse gas whose concentration...