Digital Commons Network^™

Expression Of A Dominant-Negative Mutant Of P21ras Inhibits Induction Of Nitric Oxide Synthase And Activation Of Nuclear Factor-Kb In Primary Astrocytes, Kalipada Pahan, Xiaojuan Lu, Michael J. Mckinney, Charles Wood, Faruk G. Sheikh, John R. Raymond

School of Biological Sciences: Faculty Publications

The present study underlines the importance of p21ras in regulating the inducible nitric oxide synthase (iNOS) in primary astrocytes. Bacterial lipopolysaccharides induced the GTP loading of p21ras, and the expression of a dominant-negative mutant of p21ras (Dp21ras) inhibited lipopolysaccharide-induced GTP loading in rat primary astrocytes. To delineate the role of p21ras in the induction of iNOS, we examined the effect of Dp21ras on the expression of iNOS and the production of nitric oxide. It is interesting that expression of Dp21ras markedly inhibited the production of nitric oxide and the expression of iNOS in lipopolysaccharide- and pro-inflammatory cytokine (tumor necrosis factor-a, …

Restoring Ecological Integrity Of Great Rivers: Historical Hydrographs Aid In Defining Reference Conditions For The Missouri River, David L. Galat, Robin Lipkin

United States Geological Survey: Staff Publications

Restoring the ecological integrity of regulated large rivers necessitates characterizing the natural flow regime. We applied ‘Indicators of Hydrologic Alteration’ to assess the natural range of variation of the Missouri River’s flow regime at 11 locations before (1929–1948) and after (1967–1996) mainstem impoundment. The 3768 km long Missouri River was divided into three sections: upper basin least-altered from flow regulation, including the lower Yellowstone River; middle basin inter-reservoir, and lower basin channelized. Flow regulation was associated with a reduction in magnitude and duration of the annual flood pulse, an increase in magnitude and duration of annual discharge minima, a reduction …

Geochemical Variations In Peoria Loess Of Western Iowa Indicate Paleowinds Of Midcontinental North America During Last Glaciation, Daniel R. Muhs, E. Arthur Bettis Iii

United States Geological Survey: Staff Publications

Peoria Loess deposited in western Iowa during the last glacial maximum (LGM) shows distinct geochemical and particle-size variations as a function of both depth and distance east of the Missouri River. Geochemical and particle-size data indicate that Peoria Loess in western Iowa probably had two sources: the Missouri River valley, and a source that lay to the west of the Missouri River. Both sources indicate that LGM paleowinds in western Iowa had a strong westerly component, similar to interpretations of previous workers. A compilation of loess studies in Iowa and elsewhere indicates that westerlv winds were dominant during loess transport …

Effects Of Topography And Soil Properties On Recharge At Two Sites In An Agricultural Field, Geoffrey N. Delin, Richard W. Healy, Matthew K. Landon, John Karl Böhlke

United States Geological Survey: Staff Publications

Field experiments were conducted from 1992 to 1995 to estimate ground water recharge rates at two sites located within a 2.7-hectare agricultural field. The field lies in a sand plain setting in central Minnesota and is cropped continuously in field corn. The sites are located at a topographically high (upland) site and a topographically low (lowland) site in an effort to quantify the effects of depression focusing of recharge. Three site-specific methods were used to estimate recharge rates: well hydrograph analysis, chlorofluorocarbon age dating, and an unsaturated zone water balance. All three recharge methods indicated that recharge rates at the …

Holocene Environmental And Climatic Change In The Northern Great Plains As Recorded In The Geochemistry Of Sediments In Pickerel Lake, South Dakota, Walter E. Dean, Antje Schwalb

United States Geological Survey: Staff Publications

The sediments in Pickerel Lake, northeastern South Dakota, provide a continuous record of climatic and environmental change for the last 12000 yr. Sediments deposited between 12 and 6 ka (radiocarbon) show extreme variations in composition, oxygen and carbon isotopic composition of bulk carbonate, carbon isotopic composition of organic matter, and magnetic susceptibility. These variations reflect changes in sources of moisture, regional vegetation types, precipitation-evaporation balance, ground- and surface-water influx, water residence time, erosion, lake productivity, water level, and water temperature. The total carbonate content of late Pleistocene sediments steadily increased from <20% at the base of the core to as much as 80% in sediments deposited between 11 and 9 ka. By about 8 ka, the total carbonate content of the sediments had declined to about 40% where it remained with little variation for the past 8 kyr, suggesting relatively stable conditions. There are marked increases in values of δ¹³C and δ¹⁸O in bulk carbonate, …

Viability Of Piping Plover Charadrius Melodus Metapopulations, Jonathan H. Plissner, Susan M. Haig

United States Geological Survey: Staff Publications

The meta-population viability analysis package, vortex, was used to examine viability and recovery objectives for piping plovers Charadrius melodus, an endangered shorebird that breeds in three distinct regions of North America. Baseline models indicate that while Atlantic Coast populations, under current management practices, are at little risk of near-term extinction, Great Plains and Great Lakes populations require 36% higher mean fecundity for a significant probability of persisting for the next 100 years. Meta-population structure (i.e. the delineation of populations within the meta-population) and inter-population dispersal rates had varying effects on model results; however, spatially-structured meta-populations exhibited lower viability than …

Geomorphometry – Diversity In Quantitative Surface Analysis, Richard J. Pike

United States Geological Survey: Staff Publications

A widening variety of applications is diversifying geomorphometry (digital terrain modelling), the quantitative study of topography. An amalgam of earth science, mathematics, engineering and computer science, the discipline has been revolutionized by the computer manipulation of gridded terrain heights, or digital elevation models (DEMs). Its rapid expansion continues. This article reviews the remarkable diversity of recent morphometric work in 15 selected topics and discusses their significance and prospects. The quantitative analysis of industrial microsurface topography is introduced to the earth science community. The 14 other topics are Internet access to geomorphometry; global DEMs; DEM modelling of channel networks; …

Single-Dilution Enzyme-Linked Immunosorbent Assay For Quantification Of Antigen-Specific Salmonid Antibody, Stewart W. Alcorn, Ronald J. Pascho

United States Geological Survey: Staff Publications

An enzyme-linked immunosorbent assay (ELISA) was developed on the basis of testing a single dilution of serum to quantify the level of antibody to the p57 protein of Renibacterium salmoninarum in sockeye salmon (Oncorhynchus nerka). The levels of antibody were interpolated from a standard curve constructed by relating the optical densities (OD) produced by several dilutions of a high-titer rainbow trout (O. mykiss) antiserum to the p57 protein. The ELISA OD values produced by as many as 36 test sera on each microplate were compared with the standard curve to calculate the antigen-specific antibody activity. Repeated …

Natural And Anthropogenic Influences On The Distribution Of The Threatened Neosho Madtom In A Midwestern Warmwater Stream, Mark L. Wildhaber, Vernon M. Tabor, Daniel W. Mulhern, Kenneth L. Powell, Scott P. Sowa

United States Geological Survey: Staff Publications

We attempted to discern the contributions of physical habitat, water chemistry, nutrients, and contaminants from historic lead-zinc mining activities on the riffle-dwelling benthic fish community of the Spring River, a mid western warm water stream that originates in Missouri and flows into Kansas and Oklahoma. The Spring River has a fish community that includes the Neosho madtom Noturus placidus, a species federally listed as threatened. Although anthropogenic factors such as contaminants limited populations and densities of fishes, an integrated assessment of natural and anthropogenic factors was necessary to effectively estimate the influence of the latter. Fish populations in the …

The Effect Of Rock Creep On The Morphology Of Steep-Sloped Sections Of The Niagara Escarpment (Ontario), John Barlow

Theses and Dissertations (Comprehensive)

The thesis addresses the post-glacial development of the Niagara Cuesta between Hamilton and Collingwood. Conventional thinking on the escarpment during the Holocene suggests that the present morphology developed rapidly following deglaciation due to periglacial processes (Straw, 1966/Tovell 1992). The disruption of the preglacial drainage pattern by drift has meant the escarpment has not been subject to extensive fluvial action along its base, resulting in an extremely slow rate of retreat (Bird, 1980). The concept that the escarpment is a relict feature therefore pervades the modem literature. The apparent motion of the blocks at the face of the escarpment (Hintz, I997) …

Examination Of The Role Of Macropores And Subsurface Drainage In The Delivery Of Nitrogen Trioxide-Nitrogen To A Small First-Order Agricultural Stream In Southern Ontario, Abraham House

Theses and Dissertations (Comprehensive)

Agricultural practices may result in nitrate losses, diminished surface water quality and widespread groundwater aquifer contamination. Many works have identified preferential flow through macropores as an important feature that may increase nitrate losses. Subsurface drainage collectors may intercept preferential flow and indicate changing unsaturated/saturated processes. Antecedent conditions are important in determining runoff response. It is unclear how tile drains modify the antecedent soil moisture regime and water tables in near stream areas. Vegetated riparian buffer zones found beetween agricultural fields and watercourses may attenuate nitrate in shallow groundwater pathways. However, little work recognizes the close proximity of buffer strips and …

Ce-Qual-W2 Version 3: Hydrodynamic And Water Quality River Basin Modeling, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

CE-QUAL-W2 is a two-dimensional (longitudinal-vertical) water quality and hydrodynamic computer simulation model that was originally developed for deep, long, and narrow waterbodies. The current model, Version 2, has been used in over 200 river, reservoir/lake, and estuary applications throughout the U.S. and abroad. Version 2, though, cannot accommodate systems that have a significant sloping water surface since the vertical coordinate system is aligned with gravity and vertical accelerations are neglected. The governing equations for CE-QUAL-W2 were re-derived so that it could be applied to entire river basins including river-estuary, lake-river, and reservoir-river systems with channel slopes. This re-derivation is one …

Modeling The Bull Run River-Reservoir System, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

The City of Portland, Water Bureau currently operates 2 Bull Run reservoirs, Reservoir #2 and Reservoir #1 as a water supply source in the Bull Run watershed shown in Figure 1 and Figure 2. The Water Bureau wants to operate their water supply system in order to meet both water supply objectives and fish habitat objectives downstream of the Bull Run reservoirs in Bull Run River. In addition, a third Bull Run reservoir has been proposed as an additional water supply source. This reservoir also may be used to meet water supply and fish habitat objectives in Bull Run River. …

Variation Of Constitutive Model Formulation On Analytical Cake Filtration Models, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

Constitutive properties are required to model porosity, effective stress, porewater pressure, or permeability during cake filtration. By using an analytical cake filtration model based on Tiller (1975) with various constitutive property formulations, predictions of effective stress, permeability, and porosity distributions in a filter cake can be made. This analytical approach was only valid when spatially average values of porosity and pressure differential were constant over time. Several different constitutive property formulations were compared to data of effective stress and permeability as a function of porosity for kaolin clay in water. Also the spatial distribution of porosity in a filter cake …

Nitrogen Isotopic Composition Of Pore Water Ammonium, Blake Ridge, Site 997, Odp Leg 164, Walter S. Borowski, Charles K. Paull

EKU Faculty and Staff Scholarship

Ammonium (NH4 +) concentration profiles in piston-core sediments of the Carolina Rise and Blake Ridge generally have linear concentration profiles within the sulfate reduction zone (Borowski, 1998). Deep Sea Drilling Project (DSDP) Site 533, located on the Blake Ridge, also displayed a linear ammonium concentration profile through the sulfate reduction zone and the profile linearity continues into the upper methanogenic zone to a depth of ~200 meters below seafloor (mbsf), where the first methane gas hydrates probably occur (Jenden and Gieskes, 1983; Kvenvolden and Barnard, 1983). Sediments from the Ocean Drilling Program (ODP) Leg 164 deep holes (Sites 994, 995, …

Significance Of Anaerobic Methane Oxidation In Methane-Rich Sediments Overlying The Blake Ridge Gas Hydrates, Walter S. Borowski, Tori M. Hoehler, Mark J. Alperin, Namcy M. Rodriguez, Charles K. Paull

EKU Faculty and Staff Scholarship

A unique set of geochemical pore-water data, characterizing the sulfate reduction and uppermost methanogenic zones, has been collected at the Blake Ridge (offshore southeastern North America) from Ocean Drilling Program (ODP) Leg 164 cores and piston cores. The δ13 C values of dissolved CO2(Σ CO2) are as 13 C-depleted as –37.7‰ PDB (Site 995) at the sulfate-methane interface, reflecting a substantial contribution of isotopically light carbon from methane. Although the geochemical system is complex and difficult to fully quantify, we use two methods to constrain and illustrate the intensity of anaerobic methane oxidation in Blake Ridge sediments. An estimate using …

Geologic Map Of The Lima 30' X 60' Quadrangle, Southwest Montana, J. D. Lonn, B. Skipp, E. T. Ruppel, Susanne U. Janecke, W. J. Perry, J. W. Sears, M. J. Bartholomew, M. C. Stickney, W. J. Fritz, H. A. Hurlow, R. C. Thomas

Geosciences Faculty Publications

No abstract provided.

Revised Glacial Margins And Wisconsin Meltwater Paleoflood Hydrology In Slippery Rock Creek Basin, Central Western Pennsylvania, Gary John D'Urso

Graduate Theses, Dissertations, and Problem Reports (ETD)

Glacial margins mapped in Slippery Rock Creek basin during the 1950s are problematic. The number of sedimentological, mineralogical, petrological, and textural analyses used to distinguish glacial drifts in the southern portion of the basin were inadequate to resolve the margins. Furthermore, misidentification of man-made deposits as glacial drift led to erroneous interpretations regarding the extent and character of pre-Wisconsin glacial deposits, and appears to have influenced subsequent soil mapping. Canadian Shield erratic weathering was the primary tool used in this study to re-investigate the glacial margins. Erratics display one of three distinctive weathering rinds, so glacial deposits can be differentiated …

Iron And Manganese In The Ross Sea, Antarctica: Seasonal Iron Limitation In Antarctic Shelf Waters, Peter N. Sedwick, Giacomo R. Ditullio, Denis J. Mackey

OES Faculty Publications

Dissolved iron and manganese and total dissolvable iron were measured in water column samples from the Polynya Region of the southern Ross Sea in cruises in Nov.-Dec. 1994 (spring 1994) and Dec. 1995 to Jan. 1996 (summer 1995). Iron and manganese addition bottle incubation experiments were also performed on these cruises to assess the nutritional sufficiency of ambient iron and manganese concentrations for phytoplankton growth. Generally high dissolved iron concentrations (>0.5 nM) and relatively complex iron and manganese vertical profiles were obtained in spring 1994 vs. summer 1995. Dissolved iron concentrations in the upper water column averaged 1.0 nM …

Civilian Conservation Corps Rubble And Masonry Dams And Gully Morphology In Northeastern Iowa, Timothy Robert Beerman

Dissertations and Theses @ UNI

The Civilian Conservation Corps (CCC) was created in 1933 in an effort to help solve the problems associated with the lack of jobs for young men, the nations dwindling natural resources, and problems associated with soil erosion. The CCC's work in Iowa was primarily in the areas of reforestation and erosion control. Company 1749 of Cresco, Iowa stands out as an example of how the CCC worked to halt erosion. As a part of their erosion-control strategy, Company 1749 built a large number of rubble and masonry dams on gullies. These dams were designed to trap sediments and prevent further …

Dolomitization And Dolomite Neomorphism: Trenton And Black River Limestones (Middle Ordovician) Northern Indiana, U.S.A., M. I N Chan, Jay M. Gregg, Kevin L. Shelton

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Trenton and Black River Limestones are dolomitized extensively along the axis of the Kankakee Arch in Indiana, with the proportion of dolomite decreasing to the south and southeast of the arch. Planar and nonplanar dolomite replacement textures and rhombic (type 1) and saddle (type 2) void-filling dolomite cements are present. Three stages of dolomitization, involving different fluids, are inferred on the basis of petrographic and geochemical characteristics of the dolomites. Nonferroan planar dolomite has relatively high δ18O values (-1.8 to -6.1‰ PDB) and has ⁸⁷Sr/⁸⁶Sr ratios (0.70833 to 0.70856) that overlap those of Middle Ordovician seawater. …

Hydrogeology And Paleohydrology In The Williamson River Basin, Klamath County, Oregon, Jeffrey Scott Conaway

Dissertations and Theses

Stress on the water resources of the Williamson River basin has led to their regulation to protect important habitat. Quantification of this resource is required for accurate regulation. A portion of this study is a hydrogeologic reconnaissance that suggests directions for future work. Measured discharge and deuterium isotope data from points above and below the Williamson River canyon indicate that the river receives 99% of its discharge from ground water during periods of low flow. The principle aquifer of the southern Klamath Marsh is a fractured basalt, while continental sediments that are up to 200 m thick provide high artesian …

Late Quaternary Fossil Mammals And Last Occurrence Dates From Caves At Barahona, Puerto Rico, Donald A. Mcfarlane

WM Keck Science Faculty Papers

Puerto Rico supported at least five genera of endemic terrestrial mammals in the late Quaternary, all of which are extinct. Whether these animals died out in the late Pleistocene, the mid-Holocene, or in post-Columbian time has not been established. This paper is the first attempt at radiometrically dating the 'last occurrences' of these taxa, together with the first unambiguous descriptions of localities reported by previous workers. Last occurrence dates for Nesophontes, Elasmodontomys and Heteropsomys are shown to be mid-Holocene and overlap with Amerindian occupation of the island. Acratocnus is known only from the late Pleistocene. No Puerto Rican taxon has …

Investigating Ground And Surface Water In The Republican River Basin Of Nebraska Using Water Chemistry And Environmental Isotopes, Jennifer J. Schellpeper

School of Natural Resources: Dissertations, Theses, and Student Research

Recent legal battles concerning water use initiated an investigation of the stream/aquifer relationships in the Republican River Basin located in southwest Nebraska. Ground and surface water was analyzed for tritium, deuterium, ¹⁸O, and major ions. Temperature, pH, conductivity and alkalinity were determined on-site. Samples were collected during 1997 and 1998 from irrigation wells throughout the entire basin. Localized interactions between groundwater and surface water were examined during twenty-four hour pump tests performed on the irrigation wells screened in the alluvium along the river valley and its tributaries. These data show there are differences between the ground and surface waters …

Ecology Of Elk In Northwestern Nebraska: Demographics, Effects Of Human Disturbance, And Characteristics Of Calving Habitat, Bruce A. Stillings

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.

Intelligent Visualization And Automated Processing For Large Scale Geographic Information Systems, Yu Jiang

All-Inclusive List of Electronic Theses and Dissertations

This research focuses on developing a new output system that compacts maps in multiple projections into a single Geographic Information System (GIS) without visual errors, through constructing a discrete GIS database that is managed by a Relational Data Base Management System (RDBMS). Unlike in a traditional large GIS database, the data are "physically discrete but logically continuous." In a new discrete GIS database, every map keeps its individuality without a relationship to any other map, and the relationships among the maps are centrally managed by a RDBMS. A study site was chosen at the boundary of the state of Indiana …

The Effect Of Divalent Cations On The Prophenoloxidase Enzyme Cascade Activity In The Freshwater Crayfish Cambarus Latimanus, Hans Skailand Eikaas

Theses and Dissertations

The effect of divalent cations such as cadmium, calcium, copper, lead and magnesium upon the prophenoloxidase system (proPO) was studied in hemocytes of the crayfish Cambarus latimanus. It was demonstrated that cadmium, calcium, copper and lead increased proPO activity significantly, whereas magnesium had no statistically significant effect on the system. Also, the molecular weight of the proPO enzyme was estimated using SDS-PAGE and found to be approximately 76 kDa.

Local And Landscape Factors Affecting Nest Site Selection And Nest Success Of Burrowing Owls In Western Nebraska, Rebecca T. Ekstein

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.

Mineral Paragenesis And Ore Fluids At The Turquoise Ridge Gold Deposit, Nevada, Michiko Shigehiro

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this study, mineral assemblages and related fluid inclusions at the Turquoise Ridge Carlin-type gold deposit were examined to answer the following questions: (1) What is the ore-stage mineral paragenesis? (2) At what pressures and temperatures did the deposits form? (3) What are the sources of ore fluids?

Pyrite with gold, jasperoid quartz, stibnite, orpiment, realgar, and calcite were successively deposited at Turquoise Ridge. Microthermometric data and isotopic ratios of inclusion fluids in ore-related minerals indicate entrapment of multiple generations of fluids in pre-ore, ore-, and late-ore stage minerals. Primary fluid inclusions in an ore-stage jasperoid quartz crystal have salinities …

Calibration, Installation Techniques, And Initial Measurements For Vertical Resistivity Probes Used In Hydrogeologic Investigations, Jeffrey Mark Groncki

Masters Theses

Vertical Resistivity Probes (VRPs) are being increasingly used in a variety of applications where detailed vertical resistivity information in both the vadose and saturated zones is needed. All the different possible array types and spacings must be calibrated for the effect of the 2" (outer diameter) insulating PVC cylinder on which the electrodes are mounted. Apparent resistivities must be corrected by calibration factors. Varying the installation parameters greatly influences the measured apparent resistivity because of the disturbed annulus and the composition of the backfill materials. Bentonite slurry is necessary for the installations to keep the electrodes in good contact with …