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Specific Salt Effects On The Formation And Thermal Transitions Among Β-Lactoglobulin And Pectin Electrostatic Complexes, Stacey Ann Hirt

Open Access Theses

Factors of ion specificity and ionic strength (I~0-100) were studied in the electrostatic complex formation and protein particle formation by thermal treatment for a β-lactoglobulin and pectin system. ζ-potential showed β-lactoglobulin and pectin began to interact near pH 5.50 and interactions were strengthened with decrease in pH. Visible light turbidimetry and light scattering at 90° revealed a trend in critical pH transitions for electrostatic complex formation based on both the ionic strength and the anion of the salt species, while effects of the monovalent cation was insignificant. Critical pH values for complex formation and separation (pHc and pHΦ) decreased with …

Estimation Of Watershed Nitrate Loads On Drained Agricultural Lands, Yan Jiang

Open Access Theses

Estimation of nutrient load is critical for many applications in water quality management; however, infrequent data monitoring and measurement error could raise considerable uncertainty in the load estimations. The objectives of this study were to quantify the overall uncertainty in annual nitrate-N load estimates, and develop a statistical model to predict nitrate loads based on subsurface drainage characteristics in Indiana watersheds. Nitrate was selected as the study object because of the high loads common in Midwestern streams, and its important influence on hypoxia in the Gulf of Mexico.

A standard error propagation method was used to quantify the uncertainty from …

Design And Use Of An Adjustable Clearance Flailing Knife Biomass Shredder To Mechanically Increase Particle Surface Area, Shawn Gregory Ehlers

Open Access Theses

A flailing knife shredder was designed and tested as an alternative to a hammermill for processing biomass. The machine was comprised of two cylinders with four rungs, each with five free-swinging blades. Each of the two cylinders had adjustable clearance hoods and variable speed drives. Energy usage, output characteristics and device capacities were compared with corn stover processed at moisture contents (MC) of 10%, 35% and 50% wet basis (WB). The hammermill produced a more uniform particle size distribution in comparison to the shredder. Accessibility, indicated by conductivity index, to plant constituents, revealed that the method of treatment was not-significant …

Rheological Properties Of Gluten Free Dough Systems, Stephany Aurea Tandazo

Open Access Theses

Bread is the one of the oldest processed foods and a major wheat based product. The basic process involves mixing of ingredients until the flour is converted into dough, followed by baking the dough into a loaf. A very important step in breadmaking is to know how to make good quality dough. However, the increasing knowledge of people being diagnosed with celiac disease (gluten intolerance) has encouraged scientists to develop healthier and better quality gluten-free products that would greatly improve the quality of life of celiac patients. The main objective of this study was to create a dough system composed …

Effect Of Anaerobic Dairy Manure Co-Digestion And Effluent Solid Separation On Volatile Fatty Acids During Manure Storage, Laura Page

Open Access Theses

Volatile fatty acids (VFA) are among the most abundant organic compounds found in animal manure and act as important intermediates in the production of methane under anaerobic digestion (AD). However, VFA also contribute to odor emissions from manure. Anaerobic digestion and separation of solids may help to reduce odor pollution during manure storage and subsequent land application by reducing VFA concentrations.

Little information about the characteristics and concentrations of VFA in dairy manure related to AD is available. This thesis presents the results of VFA production during two three-month storage studies of dairy manure collected from four different sources on …

Analysis Of Sources Of Variation And Relationships Among Sow Productivity Traits, Richard L. Cutshaw

Open Access Theses

The swine industry has witnessed major changes in the past three decades in terms of selection tools and implementation of effective selection. As the pork industry continues to consolidate, it is increasingly important to be able to accurately predict and direct future performance toward increased overall profitability. Overall, sow productivity greatly affects a pork producer's ability to be profitable in the industry and have sufficient knowledge of production levels to improve the likelihood of remaining profitable into the future.

The relationships among sow productivity traits including total number born, litter birth weight, number weaned, preweaning survival, mean piglet birth weight, …

Swat Model Simulation Of Bioenergy Crop Impacts In A Tile-Drained Watershed, Chelsie Marie Werling Boles

Open Access Theses

Tile drains are an important component of agricultural production in the Midwest, and their inclusion in modeling studies is important in watersheds where they are a principal hydrologic pathway. The new tile drainage simulation method in the Soil Water Assessment Tool (SWAT) was parameterized and tile flow results were compared with reviewed literature. Streamflow, sediment, and nutrient outputs were compared to measured values and simulated crop yields were examined with respect to average county yields. Plant growth stressors were examined to account for differences between simulated and published yields. The bioenergy crop switchgrass (Panicum virgatum) was applied over …

How Population Density Influences Agricultural Intensification And Productivity: Evidence From Ethiopia, Anna Leigh Josephson

Open Access Theses

We use household-level panel data to estimate how population density impacts agricultural intensification and farm income in Ethiopia. We hypothesize that increases in population density affect agricultural intensification and farm income directly through information flows, institutional development, and reduction in transactions costs. Increases in population density also affect agricultural intensification and farm income indirectly through farm size, agricultural wage rates, and staple crop prices. We find that increases in population density lead to lower farm sizes, which has major implications for agricultural intensification and household well-being. Our analysis indicates that increases in population density cause farmers to purchase more inorganic …

Effects Of Housing And Calcium-Deficient Diet On Health And Egg Production In Bovans Brown Hens., Jiaying Hu

Open Access Theses

Public concern about the welfare of hens kept in conventional cages has become an important issue worldwide. The conventional cage system has been banned by the European Union since 2012. Several housing systems, including free range, have been developed as welfare friendly alternatives to the conventional cage system. Experiment 1, the study examined the effects of housing environment, conventional cages vs. floor pens, on hens' health and egg production. A total of 84 19-wk-old Bovans Brown hens were randomly assigned into 2-bird cage with 12 replications (n=12), providing 968 cm2 floor space per hen or 10-bird floor pen with 6 …

A Land Data Assimilation System (Ldas) Based Dataset For Regional Agro-Climatic Assessments, Xing Liu

Open Access Theses

This study is part of a USDA sponsored project ----Useful to Usable (U2U): "Transforming Climate Variability and Change Information for Cereal Crop Producers". The broader objective includes improving farm resilience and profitability in the U.S. Corn Belt region by transforming existing climate/weather data into usable knowledge and tools for the agricultural community.

The specific tasks of this research are: (1) Build a high-resolution (4 km, daily) agro-climatic dataset using a Land Data Assimilation System (LDAS). (2) Estimate regional corn yield across the Corn Belt with crop models and the agro-climatic dataset. (3) Evaluate the impacts of climate variability due to …

Biology And Ecology Of Glyphosate-Resistant Giant Ragweed, Kabelo Segobye

Open Access Theses

Giant ragweed (Ambrosia trifida L.) is a competitive annual plant found in disturbed landscapes and is the most troublesome weed in Indiana and the US Corn Belt. It is one of the most common and problematic weeds in corn and soybean production. The introduction of herbicide glyphosate, N-(phosphonomethyl) glycine in early 1970's provided farmers with a better and low-cost tool to control weeds. The use of glyphosate drastically increased after the development of glyphosate resistant agronomic crops in 1996 and was use as a post-emergence selective herbicide. This led to overreliance and repeated use of glyphosate for weed control especially …

Impacts Of Insecticide Treatments On Platytetranychus Multidigituli (Acari:Tetranychidae) And Predatory Mites On Gleditsia Triacanthos Var. Inermis (Honeylocust), Adam Robert Witte

Open Access Theses

Spider mite outbreaks can occur in urban forests after insecticides are applied to control early season pests. We used thornless honeylocust (Gleditsia triacanthos var. inermis) and honeylocust spider mite (Platytetranychus multidigituli) as a model to investigate this phenomenon by applying both topical and systemic insecticides to treat early season pests of honeylocust. Impacts of these applications on populations of P. multidigituli and its associated predatory mites were assessed. Early season applications of bifenthrin caused outbreaks of honeylocust spider mite and drastically reduced phytoseiids but not the stigmaeid mite, Zetzellia mali. In contrast later season applications suppressed populations of P. multidigituli. …

A Spatially Explicit Watershed Scale Optimization Of Cellulosic Biofuels Production, Jingyu Song

Open Access Theses

Producing biofuels from energy crops is one such alternative. They can result in relatively lower greenhouse gas emissions compared to traditional energy sources. Up to now, corn grain is the most researched energy crop. Cellulosic perennial crops such as switchgrass, miscanthus and fast growing trees are also promising energy crops and are expected to help with the energy supply. The 2007 Renewable Fuel Standard requires 16 billion gallons of a total of 36 billion gallons of renewable fuels to be cellulosic biofuels by 2022. Many studies are being done to evaluate costs and feasibility of different potential feedstocks and the …