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Search Results: 1 - 10 of 97568 matches for " Eric W. Peterson "
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Evaluating Subdivisions for Identifying Extraneous Flow in Separate Sanitary Sewer Systems  [PDF]
Adam Lanning, Eric W. Peterson
Journal of Water Resource and Protection (JWARP) , 2012, DOI: 10.4236/jwarp.2012.46037
Abstract: Separate sanitary sewer systems are designed to convey sewage waste from municipal areas to a central treatment facility; they are not designed to handle water associated with precipitation events. However, intercept of groundwater (infiltration) and of flows through manholes or unauthorized connections (inflows) introduces rainwater into the sanitary sewer system. Infiltration/Inflow (I/I) increases the costs associated with treatment and can create additional environmental problems. Identifying and quantifying the volume I/I can be complicated and costly. A simple quantitative method was developed to quantify the extent of I/I occurring in sewer sheds. The method uses measured sewer flows, water usage, precipitation values, and land cover data to calculate the volume of extraneous flows. To assess its utility, the method was used to compare two urban sewer sheds, Holiday Knolls and Eagle View. Both sewer sheds showed evidence of I/I in excess of 200 gallons per day per inch-mile of sewer pipe (gpd/in-mile). Holiday Knolls, the older subdivision had an average I/I of 1912 gpd/in-mile, while Eagle View had an average of 1143 gpd/in-mile. The devel- oped method provided simple means to calculate I/I and to identify sewer sheds in need of repair.
Variation of Hyporheic Temperature Profiles in a Low Gradient Third-Order Agricultural Stream—A Statistical Approach  [PDF]
Vanessa Beach, Eric W. Peterson
Open Journal of Modern Hydrology (OJMH) , 2013, DOI: 10.4236/ojmh.2013.32008
Abstract: Sediment size governs advection, controlling the hydraulic conductivity of the stratum, and conduction, influencing the amount of surface area in contact between the sediment particles. To understand the role of sediment particle size on thermal profiles within the hyporheic zone, a statistical approach, involving general summary statistics and time series cross-correlation, was employed. Data were collected along two riffles: Site 1: gravel (d50 = 3.9 mm) and Site 2: sand (d50 =0.94 mm).Temperature probe grids collected 15-minute temperature data at 30, 60, 90, and140cm below the streambed surface over a 6 month period. Surface water and air temperature were recorded. Diel temperature signal penetration depth was limited to the upper 30cm of the streambed and was driven by advection. Surface seasonal trends were detected at greater depths, indicating that thermal pulses are transmitted initially by advection and by conduction to areas deeper in the hyporheic zone. Site 1 showed a high degree of thermal heterogeneity via a localized downwelling zone within a gaining stream environment. Site 2 exhibited a vertically and horizontally homogenized thermal environment attributed to an increased amount of sand sediments that limited advection and significant groundwater discharge that mediated the effects of downwelling surface water.
The Effects of Surface Water Velocity on Hyporheic Interchange  [PDF]
Timothy Sickbert, Eric W. Peterson
Journal of Water Resource and Protection (JWARP) , 2014, DOI: 10.4236/jwarp.2014.64035
Abstract:

When evaluating hyporheic exchange in a flowing stream, it is inappropriate to directly compare stream stage with subsurface hydraulic head (h) to determine direction and magnitude of the gradient between the stream and the subsurface. In the case of moving water, it is invalid to ignore velocity and to assume that stage equals the net downward pressure on the streambed.  The Bernoulli equation describes the distribution of energy within flowing fluids and implies that net pressure decreases as a function of velocity, i.e., the Venturi Effect, which sufficiently reduces the pressure on the streambed to create the appearance of a downward gradient when in fact the gradient may be upward with stream flow drawing water from the subsurface to the surface. A field study correlating the difference between subsurface head and stream stage in a low-gradient stream indicates that the effect is present and significant: shallow subsurface head increases less quickly than stage while deeper subsurface head increases more quickly. These results can substantially improve conceptual models and simulations of hyporheic flow.

Three-Dimensional Geologic Modeling and Groundwater Flow Modeling above a CO2 Sequestration Test Site  [PDF]
Erin Carlock, Eric W. Peterson, David H. Malone
Open Journal of Modern Hydrology (OJMH) , 2016, DOI: 10.4236/ojmh.2016.63015
Abstract: As temperatures rise and climate change becomes an increasingly important issue, geologic carbon dioxide (CO2) sequestration is a viable solution for reducing greenhouse gas emissions. Subsurface 3-D modeling and groundwater flow modeling were completed as a component of a CO2 sequestration feasibility study in the city of Decatur, Illinois. The Decatur Archer Daniels Midland Company Ethanol Plant (ADM) serves as the injection site for a CO2 sequestration project within a deep saline reservoir. Petrel was successfully used to model the glacial deposits in the area. The 3-D geologic model shows the Peoria Silt, Wedron Formation, and Cahokia Formation at the surface with the Wedron Formation holding up the steep slopes along the east and west banks of Lake Decatur. The groundwater flow model outlined the location of a local groundwater divide and showed flow from the injection site would flow towards Lake Decatur, reaching the lake in 80 days.
The Morava E-theory of Eilenberg-Mac Lane spaces
Eric Peterson
Mathematics , 2011,
Abstract: We deform the Ravenel-Wilson computation of the Morava K-homology of Eilenberg-Mac Lane spaces to obtain a similar description of their completed Morava E-homology. This yields both a cohomological description and an interpretation on the level of formal schemes: the scheme associated to the E-cohomology of the space K(Z/p^infty, q) is the qth exterior power of the p-divisible group associated to the versal infinitesimally deformed formal group over Lubin-Tate space.
Toxicology evaluation of radiotracer doses of 3'-deoxy-3'-[18F]fluorothymidine (18F-FLT) for human PET imaging: Laboratory analysis of serial blood samples and comparison to previously investigated therapeutic FLT doses
Eric Turcotte, Linda W Wiens, John R Grierson, Lanell M Peterson, Mark H Wener, Hubert Vesselle
BMC Medical Physics , 2007, DOI: 10.1186/1471-2385-7-3
Abstract: Twenty patients gave consent to a 18F-FLT injection, subsequent PET imaging, and blood draws. For each patient, blood samples were collected at multiple times before and after 18F-FLT PET. These samples were assayed for a comprehensive metabolic panel, total bilirubin, complete blood and platelet counts. 18F-FLT doses of 2.59 MBq/Kg with a maximal dose of 185 MBq (5 mCi) were used. Blood time-activity curves were generated for each patient from dynamic PET data, providing a measure of the area under the FLT concentration curve for 12 hours (AUC12).No side effects were reported. Only albumin, red blood cell count, hematocrit and hemoglobin showed a statistically significant decrease over time. These changes are attributed to IV hydration during PET imaging and to subsequent blood loss at surgery. The AUC12 values estimated from imaging data are not significantly different from those found from serial measures of FLT blood concentrations (p = 0.66). The blood samples-derived AUC12 values range from 0.232 ng*h/mL to 1.339 ng*h/mL with a mean of 0.802 ± 0.303 ng*h/mL. This corresponds to 0.46% to 2.68% of the lowest and least toxic clinical trial AUC12 of 50 ng*h/mL reported by Flexner et al (1994). This single injection also corresponds to a nearly 3,000-fold lower cumulative dose than in Flexner's twice daily trial.This study shows no evidence of toxicity or complications attributable to 18F-FLT injected intravenously.3'-Deoxy-3'-[18F]fluorothymidine (18F-FLT) is a new tracer for positron emission tomography (PET) being evaluated at several centers across the United States and worldwide. The interest generated by FLT as a radiotracer stems from its potential as a proliferation tracer that would accumulate in tumors in proportion to their growth rate.FLT, a thymidine nucleoside analog, undergoes the same first metabolic step as thymidine when it is 5'-monophosphorylated by the cytosolic enzyme thymidine kinase-1 (TK-1), however, the 3' substitution prevents further inc
Approaching Cave Level Identification with GIS: A Case Study of Carter Caves
Brianne S. Jacoby,Eric W. Peterson,John C. Kostelnick,Toby Dogwiler
ISRN Geology , 2013, DOI: 10.1155/2013/160397
Abstract: Cave passages that are found at similar elevations are grouped together and called levels. The current understanding is that passages within a level are speleogenetically linked to a common static baselevel or stratigraphic control. Cave levels have provided an interpretive framework for deciphering cave development, landscape evolution, and climatic changes. Cosmogenic dating has been successfully used to interpret levels in Mammoth Cave and the Cumberland Plateau; however, this technique is expensive and there are limited funding resources available. Geographic information systems may be used as preliminary procedures to identify cave levels and constrain the timing of level development. A GIS method is applied to the Carter Cave system in northeastern Kentucky. Cave entrance elevations along stream valleys were found by extracting elevation values from a ?m digital elevation model. Using a histogram generated from the frequency of cave elevations and a natural breaks classifier, four cave levels were identified in the Carter Cave system. This work improves the understanding of the Carter Cave system evolution and contributes toa methodology that can be used to ascertain an erosion history of karst systems. 1. Introduction In fluviokarst, dissolution creates a system vertically and horizontally connecting surface and subsurface flow paths. Passage development is dependent on the elevation of base flow, stratigraphy, the diversion of water in the unsaturated zone to lower levels, discharge variations, and variations in chemistry [1]. Long periods of static base level with active dissolution allow for large passages to develop in discrete levels, graded to the regional hydrologic network. When river incision occurs as a result of regional base level lowering, groundwater flow is diverted to lower elevations [1–3]. Subsequently, dissolution and passage enlargement is limited or stopped in the abandoned upper levels as karst development becomes focused at the new base level. Alternating sequences of base level incision and aggradation results in a complex overprinting of level development with transitional passage morphologies and deposition or removal of broadly distributed sediment packages [4]. Deciphering the history of speleogenesis in such systems, including the delineation of cave levels, provides insight into the history of past base level changes and the associated glacio-eustatic or tectonic processes. Passages that are created by static base level and correlate with other passages at similar elevations are grouped together and considered a
Comparison of the effects of erythropoietin and anakinra on functional recovery and gene expression in a traumatic brain injury model
Gail D. Anderson,Todd C. Peterson,Eric D. Kantor,James W. MacDonald,Michael R. Hoane
Frontiers in Pharmacology , 2013, DOI: 10.3389/fphar.2013.00129
Abstract: The goal of this study was to compare the effects of two inflammatory modulators, erythropoietin (EPO) and anakinra, on functional recovery and brain gene expression following a cortical contusion impact (CCI) injury. Dosage regimens were designed to provide serum concentrations in the range obtained with clinically approved doses. Functional recovery was assessed using both motor and spatial learning tasks and neuropathological measurements conducted in the cortex and hippocampus. Microarray-based transcriptional profiling was used to determine the effect on gene expression at 24 h, 72 h, and 7 days post-CCI. Ingenuity Pathway Analysis was used to evaluate the effect on relevant functional categories. EPO and anakinra treatment resulted in significant changes in brain gene expression in the CCI model demonstrating acceptable brain penetration. At all three time points, EPO treatment resulted in significantly more differentially expressed genes than anakinra. For anakinra at 24 h and EPO at 24 h, 72 h, and 7 days, the genes in the top 3 functional categories were involved in cellular movement, inflammatory response and cell-to-cell signaling. For EPO, the majority of the genes in the top 10 canonical pathways identified were associated with inflammatory and immune signaling processes. This was true for anakinra only at 24 h post-traumatic brain injury (TBI). The immunomodulation effects of EPO and anakinra did not translate into positive effects on functional behavioral and lesion studies. Treatment with either EPO or anakinra failed to induce significant beneficial effects on recovery of function or produce any significant effects on the prevention of injury induced tissue loss at 30 days post-injury. In conclusion, treatment with EPO or anakinra resulted in significant effects on gene expression in the brain without affecting functional outcome. This suggests that targeting these inflammatory processes alone may not be sufficient for preventing secondary injuries after TBI.
Role of Multiple High-Capacity Irrigation Wells on a Surficial Sand and Gravel Aquifer  [PDF]
Logan C. Seipel, Eric W. Peterson, David H. Malone, Jason F. Thomason
Journal of Geoscience and Environment Protection (GEP) , 2016, DOI: 10.4236/gep.2016.45005
Abstract: Within McHenry County, IL, the fastest growing county in Illinois, groundwater is used for 100% of the water needs. Concerns over water resources have prompted the investigation of the surficial sand and gravel aquifers of the county. While the eastern portion of the county is urbanizing, the western portion remains devoted to agriculture. High-capacity irrigation wells screened within the surficial sand and gravel aquifer are used for crop production. To assess the impacts of the irrigation wells on the aquifer, a groundwater flow model was developed to examine five different scenarios reflecting drought conditions and increased pumping. Results show that the surficial sand and gravel aquifer is capable of meeting current water demands even if recharge is decreased 20% and pumping is increased 20%. The additional loss of discharge and increases in pumping result in head differences throughout the aquifer.
Modeling the Sediment Fill of the Upper Troy Pre-Glacial Bedrock Valley, McHenry County, Illinois, USA  [PDF]
Jodi Lau, Jason F. Thomason, David H. Malone, Eric W. Peterson
Journal of Geoscience and Environment Protection (GEP) , 2016, DOI: 10.4236/gep.2016.46010
Abstract: The Troy Bedrock Valley (TBV) and its tributary valleys are the principal pre-glacial drainage in southern Wisconsin and northern Illinois, USA. This study focused on the headwaters of a tributary that occurs in McHenry County, IL. Drilling, geophysical surveys, and the analysis of existing geologic and water well data were used to determine the lithologic and geometric characteristics of the sediments that fill the paleovalley. A 3D geologic model of these sediments was then developed in Petrel. More than 65 m of Quaternary sediments filled the paleovalley. The model domain covers approximately 30 km2. The valley drains to the west and meanders, which is distinct from the straight course of the overlying modern Kishwaukee River. The sediments that filled the valley were subdivided into five units. These units include Illinois-age Glasford Formation coarse-grained proglacial outwash and alluvial deposits (GS2, GS1) and fine-grained lacustrine and diamicton deposits (G2 and G1). The Wisconsin-age Henry Formation sand and gravel cap the valley fill, and Cahokia alluvium buries everything.
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