Engineering Commons^™

Climate Anomalies And Primary Production In Lake Superior, Marcel L. Dijkstra

Dissertations, Master's Theses and Master's Reports - Open

This dissertation supports the modeling of primary production in Lake Superior by offering site specific kinetics and algorithms developed from lab experiments performed on the natural phytoplankton assemblage of Lake Superior. Functions, developed for temperature, light and nutrient conditions and the maximum specific rate of primary production, were incorporated in a 1D specific primary production model and confirmed to published in-situ measured rates of primary production.

An extensive data set (supporting model calibration and confirmation), with a fine spatiotemporal resolution, was developed from field measurements taken bi-weekly during the sampling seasons of 2011, 2012 and 2014; considered to be meteorologically …

Enzyme Optimization For Lignocellulose Hydrolysis Using Mechanistic Modeling, Adam S. Marlowe

Dissertations, Master's Theses and Master's Reports - Open

A novel mechanistic model for the saccharification of cellulose and hemicellulose is utilized to predict the products of hydrolysis over a range of enzyme loadings and times. The mechanistic model considers the morphology of the substrate and the kinetics of enzymes to optimize enzyme concentrations for the enzymatic hydrolysis of cellulose and hemicellulose simultaneously. Substrates are modeled based on their fraction of accessible sites, glucan content, xylan content, and degree of polymerizations. This enzyme optimization model takes into account the kinetics of six core enzymes for lignocellulose hydrolysis: endoglucanase I (EG1), cellobiohydrolase I (CBH1), cellobiohydrolase II (CBH2), and endo-xylanase (EX) …

Virus Purification, Detection And Removal, Khrupa Saagar Vijayaragavan

Dissertations, Master's Theses and Master's Reports - Open

The biopharmaceutical industry has a growing demand and an increasing need to improve the current virus purification technologies, especially as more and more vaccines are produced from cell-culture derived virus particles. Downstream purification strategies can be expensive and account for 70% of the overall manufacturing costs. The economic pressure and purification processes can be particularly challenging when the virus to be purified is small, as in our model virus, porcine parvovirus (PPV). Our efforts are focused on designing an easy, economical, scalable and efficient system for virus purification, and we focused on aqueous two-phase systems. Industry acceptable standards for virus …

Design, Synthesis And Applications Of Fluorescent And Electrochemical Probes, Giri K. Vegesna

Dissertations, Master's Theses and Master's Reports - Open

“Seeing is believing” the proverb well suits for fluorescent imaging probes. Since we can selectively and sensitively visualize small biomolecules, organelles such as lysosomes, neutral molecules, metal ions, anions through cellular imaging, fluorescent probes can help shed light on the physiological and pathophysiological path ways. Since these biomolecules are produced in low concentrations in the biochemical pathways, general analytical techniques either fail to detect or are not sensitive enough to differentiate the relative concentrations. During my Ph.D. study, I exploited synthetic organic techniques to design and synthesize fluorescent probes with desirable properties such as high water solubility, high sensitivity and …

Computational Prediction Of The Sporulation Network In Clostridium Thermocellum, Changyi Jiang

Dissertations, Master's Theses and Master's Reports - Open

Sporulation is a process in which some bacteria divide asymmetrically to form tough protective endospores, which help them to survive in a hazardous environment for a quite long time. The factors which can trigger this process are diverse. Heat, radiation, chemicals and lacking of nutrition can all lead to the formation of endospores. This phenomenon will lead to low productivity during industrial production. However, the sporulation mechanism in a spore-forming bacterium, Clostridium theromcellum, is still unclear. Therefore, if a regulation network of sporulation can be built, we may figure out ways to inhibit this process. In this study, a …

Integrated Assessment Of Anthropogenic, Climate, And Policy Induced Changes Of Phosphorus Export In The United States Laurentian Great Lakes Watersheds, Meredith Ballard Labeau

Dissertations, Master's Theses and Master's Reports - Open

Anthropogenic activities have increased phosphorus (P) loading in tributaries to the Laurentian Great Lakes resulting in eutrophication in small bays to most notably, Lake Erie. Changes to surface water quality from P loading have resulted in billions of dollars in damage and threaten the health of the world’s largest freshwater resource. To understand the factors affecting P delivery with projected increasing urban lands and biofuels expansion, two spatially explicit models were coupled. The coupled models predict that the majority of the basin will experience a significant increase in urban area P sources while the agriculture intensity and forest sources of …