Publications
These publications showcase the significant science conducted in our Science Centers.
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Transcriptional profiling of the parr–smolt transformation in Atlantic salmon
The parr–smolt transformation in Atlantic salmon (Salmo salar) is a complex developmental process that culminates in the ability to migrate to and live in seawater. We used GRASP 16K cDNA microarrays to identify genes that are differentially expressed in the liver, gill, hypothalamus, pituitary, and olfactory rosettes of smolts compared to parr. Smolts had higher levels of gill Na+/K+-ATPase activ
Authors
Laura S. Robertson, Stephen D. McCormick
Carbon dioxide stripping in aquaculture -- part II: development of gas transfer models
The basic mass transfer equation for gases such as oxygen and carbon dioxide can be derived from integration of the driving force equation. Because of the physical characteristics of the gas transfer processes, slightly different models are used for aerators tested under the non steady-state procedures, than for packed columns, or weirs. It is suggested that the standard condition for carbon dioxi
Authors
John Colt, Barnaby Watten, Tim Pfeiffer
State of the Earth’s cryosphere at the beginning of the 21st century : glaciers, global snow cover, floating ice, and permafrost and periglacial environments: Chapter A in Satellite image atlas of glaciers of the world
This chapter is the tenth in a series of 11 book-length chapters, collectively referred to as “this volume,” in the series U.S. Geological Survey Professional Paper 1386, Satellite Image Atlas of Glaciers of the World. In the other 10 chapters, each of which concerns a specific glacierized region of Earth, the authors used remotely sensed images, primarily from the Landsat 1, 2, and 3 series of sp
Authors
Richard S. Williams, Jane G. Ferrigno
Total nitrogen and suspended-sediment loads and identification of suspended-sediment sources in the Laurel Hill Creek watershed, Somerset County, Pennsylvania, water years 2010-11
Laurel Hill Creek is a watershed of 125 square miles located mostly in Somerset County, Pennsylvania, with small areas extending into Fayette and Westmoreland Counties. The upper part of the watershed is on the Pennsylvania Department of Environmental Protection 303(d) list of impaired streams because of siltation, nutrients, and low dissolved oxygen concentrations. The objectives of this study we
Authors
Ronald A. Sloto, Allen C. Gellis, Daniel G. Galeone
Comparison of two regression-based approaches for determining nutrient and sediment fluxes and trends in the Chesapeake Bay watershed
Nutrient and sediment fluxes and changes in fluxes over time are key indicators that water resource managers can use to assess the progress being made in improving the structure and function of the Chesapeake Bay ecosystem. The U.S. Geological Survey collects annual nutrient (nitrogen and phosphorus) and sediment flux data and computes trends that describe the extent to which water-quality conditi
Authors
Douglas Moyer, Robert M. Hirsch, Kenneth Hyer
Occurrence model for volcanogenic beryllium deposits
Current global and domestic mineral resources of beryllium (Be) for industrial uses are dominated by ores produced from deposits of the volcanogenic Be type. Beryllium deposits of this type can form where hydrothermal fluids interact with fluorine and lithophile-element (uranium, thorium, rubidium, lithium, beryllium, cesium, tantalum, rare earth elements, and tin) enriched volcanic rocks that con
Authors
Nora K. Foley, Albert H. Hofstra, David A. Lindsey, Robert R. Seal, Brian W. Jaskula, Nadine M. Piatak
Program SPACECAP: software for estimating animal density using spatially explicit capture-recapture models
1. The advent of spatially explicit capture-recapture models is changing the way ecologists analyse capture-recapture data. However, the advantages offered by these new models are not fully exploited because they can be difficult to implement. 2. To address this need, we developed a user-friendly software package, created within the R programming environment, called SPACECAP. This package impl
Authors
Arjun M. Gopalaswamy, J. Andrew Royle, James E. Hines, Pallavi Singh, Devcharan Jathanna, N. Samba Kumar, K. Ullas Karanth
Balancing precision and risk: should multiple detection methods be analyzed separately in N-mixture models?
Using multiple detection methods can increase the number, kind, and distribution of individuals sampled, which may increase accuracy and precision and reduce cost of population abundance estimates. However, when variables influencing abundance are of interest, if individuals detected via different methods are influenced by the landscape differently, separate analysis of multiple detection methods
Authors
Tabitha A. Graves, J. Andrew Royle, Katherine C. Kendall, Paul Beier, Jeffrey B. Stetz, Amy C. Macleod
Interbasin water transfer, riverine connectivity, and spatial controls on fish biodiversity
Background Large-scale inter-basin water transfer (IBWT) projects are commonly proposed as solutions to water distribution and supply problems. These problems are likely to intensify under future population growth and climate change scenarios. Scarce data on the distribution of freshwater fishes frequently limits the ability to assess the potential implications of an IBWT project on freshwater fis
Authors
Evan H. Campbell Grant, Heather J. Lynch, Rachata Muneepeerakul, Arunachalam Muthukumarasamy, Ignacio Rodríguez-Iturbe, William F. Fagan
Density estimation in tiger populations: combining information for strong inference
A productive way forward in studies of animal populations is to efficiently make use of all the information available, either as raw data or as published sources, on critical parameters of interest. In this study, we demonstrate two approaches to the use of multiple sources of information on a parameter of fundamental interest to ecologists: animal density. The first approach produces estimates si
Authors
Arjun M. Gopalaswamy, J. Andrew Royle, Mohan Delampady, James D. Nichols, K. Ullas Karanth, David W. Macdonald
Demonstration/validation of the snap sampler passive groundwater sampling device at the former McClellan Air Force Base
No abstract available.
Authors
L. Parker, Nathan Mulherin, T. Hall, Constance Scott, K. Gagnon, Jay Clausen, William Major, Jacob Gibs, Thomas E. Imbrigiotta, Donald Gronstal
Demonstration/validation of the Snap sampler passive groundwater sampling device
Laboratory studies and a field demonstration were conducted to determine the ability of the Snap Sampler to recover representative concentrations of several types of inorganic analytes from ground water. Analytes included non-metals, transition metals, alkaline earth metals, alkali metals, and a metalloid. In the laboratory studies, concentrations of analytes in Snap Sampler samples were com-parab
Authors
Louise Parker, Nathan Mulherin, Gordon Gooch, William Major, Richard Willey, Thomas E. Imbrigiotta, Jacob Gibs, Donald Gronstal