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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

A Metal-Analysis and Risk Assessment of Heavy Metal Uptake in Common Garden Vegetables

LeCoultre, T. D., Scheuerman, Phillip R. 01 January 2001 (has links)
No description available.
42

Data Requirements for Developing Effective Pathogen TMDLs

Dulaney, D. R., Maier, Kurt J., Scheuerman, Phillip R. 01 January 2005 (has links)
No description available.
43

Comparison of Microbial Water Quality Parameters in Four Geographically Similar Creeks In Northeast Tennessee Using Multivariate Statistical Analyses

Hall, Kimberlee K., Gallagher, L. K., Evanshen, Brian G., Maier, Kurt J., Scheuerman, Phillip R. 01 January 2007 (has links)
No description available.
44

Bacterial Source Tracking in the Sinking Creek Watershed, using Antibiotic Resistance Analysis (ARA) and Ribotyping

Gallagher, L. K., Evanshen, Brian G., Maier, Kurt J., Scheuerman, Phillip R. 01 January 2007 (has links)
No description available.
45

Application of Multivariate Statistical Analyses to Microbial Water Quality Parameters in Four Geographically Similar Creeks in Northeast Tennessee to Identify Patterns Associating Land Use to Fecal Pollution Sources

Hall, Kimberlee K., Evanshen, Brian G., Maier, Kurt J., Scheuerman, Phillip R. 01 January 2008 (has links)
No description available.
46

Using Multivariate Statistics to Identify Patterns Association Land Use to Fecal Pollution Sources.Similar Creeks in Northeast Tennessee to Identify Patterns Associating Land Use to Fecal Pollution Sources

Hall, Kimberlee K., Evanshen, Brian G., Maier, Kurt J., Scheuerman, Phillip R. 01 January 2011 (has links)
No description available.
47

Comparison Study of Sediment Microbial Enzyme Activities to Biochemical Oxygen Demand, Nitrate Concentration, Phosphate Concentration in the Sediments of a Fecally-Contaminated Stream in Northeast Tennessee Relative to Season and Land Use

Evanshen, Brian G., Maier, Kurt J., Scheuerman, Phillip R. 01 January 2006 (has links)
Microbial metabolism reacts quickly to environmental conditions. These reactions are dependent on the need for nutrients and respiration and can be measured using an assay of individual microbial enzyme activities (MEA’s). In this study, we measured MEA’s in the sediments of a stream in northeast Tennessee that had an approved fecal coliform Total Maximum Daily Load (TMDL). These values were compared to biochemical oxygen demand (BOD), phosphate concentration and nitrate concentration in the water column of this stream. Comparisons were grouped by season and land use. Stream sediments and water were collected monthly for one year and then quarterly for an additional two years at 14 sites located in agricultural, urban and forest regions. Dehydrogenase (DHA), a measure of microbial respiration, along with acid phosphatase (AcidPA), alkaline phosphatase (AlkPA), galactosidase (GalA) and glucosidase (GluA) activities were measured using colorimetric assays. BOD was determined using the standard 5-day BOD test (BOD5). Nitrate and phosphate concentrations were measured using colorimetric procedures. There were significant positive and negative correlations (p5, DHA vs. nitrate concentration, and DHA vs. phosphate concentration. Also in the fall months there were significant negative correlations between GalA and GluA vs. BOD5, and concentrations of nitrate and phosphate. There was also a negative correlation between AcidPA and BOD5. In the warmer months of spring and summer, there were positive correlations between AcidPA, AlkPA, GalA and GluA vs. the BOD5 ’s, and the concentrations of nitrate and phosphate. The only negative correlation in a warmer season was in the summer between AlkPA vs. BOD5 and phosphate concentration. No significant correlations were found by land use type. Results indicate that significant relationships may exist between MEA’s and other water quality measures (e.g. BOD5, nitrate concentration, and phosphate concentration) that could make it possible to use MEA’s as another tool for water quality assessment.
48

Comparison of Microbial Water Quality Parameters of Four Geographically Similar Creeks in Northeast Tennessee

Hall, Kimberlee K., Gallagher, L. K., Evanshen, Brian G., Maier, Kurt J., Scheuerman, Phillip R. 01 January 2006 (has links)
Four creeks within the Watauga River watershed in Northeast Tennessee are routinely monitored for water quality assessments. To identify sources and monitor remediation, Sinking Creek, Cash Hollow Creek, Buffalo Creek and Boones Creek are monitored for chemical and microbial parameters. These parameters include phosphates, nitrates, BOD and fecal coliforms. Sinking Creek is a tributary of the Watauga River with 10 miles of impaired water. Cash Hollow Creek enters the Watauga River at river mile 11.4 with 3.4 miles of impaired water. Boones Creek contains 18.6 impaired miles while the status of water quality in Buffalo Creek is not yet determined. Agricultural input is a major source of pollution for Sinking and Boones Creek. Cash Hollow Creek is impacted by a combination of sources of which urban runoff is the largest due to storm sewers and land development. Boones, Cash Hollow and Sinking Creeks are considered impaired and are on the state’s 303(d) list due to pathogen loading but only Sinking and Cash Hollow Creek have TMDLs. The seasonal and spatial patterns are more obvious for microbial than for chemical parameters. From 2002 - 2005, 14 stations on Sinking Creek were sampled quarterly. Fecal coliforms were elevated and always greater than 200 CFU/100ml for stations 1 – 5. Due to agricultural land use adjacent to stations 1 – 4, this would be expected. There was also a seasonal trend with higher concentrations found in the fall and spring. Cash Hollow Creek’s 9 stations were sampled monthly from 2002 - 2005. Although very high fecal coliforms concentrations were found, there were no obvious patterns. The 12 stations on Buffalo Creek were sampled quarterly from June 2004 to June 2005. Fecal coliform concentrations were high at station 8, which is adjacent to agricultural land. Boones Creek was sampled monthly from March 2005 to present and no obvious trends have been noted. The objective of this research is to compare patterns in these geographically similar creeks to identify any common patterns associated with various pollution sources. We will discuss the preliminary results and conclusions about the usefulness of these data to accomplish this objective.
49

Comparison Study of the Averaged Sediment Microbial Enzyme Activities in Four Fecally-Contaminated streams in the Same Watershed in Northeast Tennessee to Biochemical Oxygen Demand, Nitrate Concentration, and Phosphate Concentration

Evanshen, Brian G., Maier, Kurt J., Scheuerman, Phillip R. 01 January 2007 (has links)
Microbial enzyme activities (MEA’s) are measurements of microbial metabolism. These activities are dependent on the need for nutrients and respiration. This extended study evaluated four streams in the same watershed that had an approved fecal coliform Total Maximum Daily Load. Sediment and water samples were collected monthly for the first year of each specific stream study, and then quarterly to the end of 2006. Dehydrogenase, a measure of microbial respiration, along with acid phosphatase, alkaline phosphatase, galactosidase and glucosidase activities were measured using colorimetric assays. Biochemical oxygen demand (BOD) was determined using the standard 5-day test (BOD5). Nitrate and phosphate concentrations were measured using colorimetric procedures. Sediment MEA values were compared to the BOD, nitrate concentration and phosphate concentration in the overlying water. Seasonal means of each parameter were not significantly different (p5, nitrate concentration, and phosphate concentration). This suggests to us that MEA’s may be an alternative tool for water quality assessments.
50

Biosand Water Filter Evaluation: Pilot Study of Field Use Indicators in Cyegera, Rwanda

O'Connell, Bethesda, Slawson, Deborah, Quinn, Megan, Scheuerman, Phillip R., Ogunleye, Olushola 27 August 2018 (has links)
Diarrheal diseases are a global public health burden, killing 1.8 million people annually. Diarrhea disproportionately affects children and those in poverty. Most diarrheal cases can be prevented through safe drinking water, basic hygiene and/or sanitation measures, with drinking water interventions having the most impact on reducing diarrheal disease. There is no generally agreed-upon field method for determining biosand water filter effectiveness that is usable in low-resource communities. A pilot study was conducted of potential field use indicators, including the Colilert coliform presence/absence (P/A) test, hydrogen sulfide, alkalinity, hardness, pH, and fluorescently labeled latex microspheres. The study included both laboratory and field testing. The Colilert P/A test had the highest correlation to the United States Environmental Protection Agency standard method (IDEXX Quanti-trays), but more data are needed before making a recommendation. This study adds to understanding about evaluation of biosand water filters and provides preliminary data to address the need for a field use indicator for biosand water filters.

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