Bioresource and Agricultural Engineering Commons^™

Development Of A Decellularized Hydrogel Composite And Its Application In A Novel Model Of Disc-Associated Low Back Pain In Female Sprague Dawley Rats, David Lillyman

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Chronic low back pain is a global socioeconomic crisis compounded by an absence of reliable, curative treatments. The predominant pathology associated with chronic low back pain is degeneration of intervertebral discs in the lumbar spine. During degeneration, nerves can sprout into the intervertebral disc tissue and be chronically subjected to inflammatory and mechanical stimuli, resulting in pain. Pain arising from the intervertebral disc, or disc-associated pain, is a complex, multi-faceted disorder which necessitates valid animal models to screen therapeutics and study pathomechanisms of pain.

While many research teams have created animal models of disc degeneration, the translation of these platforms …

Optimization Of A Novel Barnes Maze Protocol For Assessing Antioxidant Treatment Of Traumatic Brain Injury, Connor C. Gee

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Current preclinical research into traumatic brain injury focuses heavily upon cellular and molecular testing to determine the effects of injury and potential benefits of neuroprotective treatments. While this may be a useful method, some argue that an increased focus on behavioral testing could lead to better clinical translation as these assays assess the longer term, downstream effects from a brain injury. The most characterized behavioral tests used in traumatic brain injury research are the spatial learning and memory paradigms, Morris Water Maze and Barnes Maze. The Morris Water Maze is the most used of theses paradigms and relies on spatial …

Development And Characterization Of A Decellularized Neuroinhibitory Scaffold Containing Matrix Bound Nanovesicles, Logan Piening

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Chronic low back pain (LBP) is a leading cause of disability but treatments for LBP are limited. Degeneration of the intervertebral disc leads to loss of neuroinhibitory sulfated glycosaminoglycans (sGAGs) which allows nerves from dorsal root ganglia (DRG) to grow into the core of the disc, leading to pain. Current treatments for LBP involve drugs that do not target the source of the pain and lack long term efficacy or use invasive surgeries with high complication rates. Treatment with a decellularized tissue scaffold that contains neuroinhibitory components may inhibit nerve growth and prevent disc-associated LBP. Here, a decellularized nucleus pulposus …

Efficient Polyhydroxyalkanoate Production By Rhodopseudomonas Palustris From Lignocellulosic Biomass, Brandi Brown

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Polyhydroxyalkanoates (PHAs) are biopolymers produced by bacteria with the potential to replace conventional plastics. However, the relatively high production costs of PHAs are keeping them from market acceptance, with approximately half of the production costs derived from the feedstock. Thus, engineering a microbe for PHA production from cheaper and renewable carbon sources is necessary to promote the valorization of PHAs. Lignocellulosic biomass is considered to be one of the most economic carbon sources in the world, and is thus an attractive candidate for cheaper production of bioplastics. Rhodopseudomonas palustris CGA009 is a metabolically robust bacterium capable of catabolizing lignin breakdown …

Preclinical Development Of Single Walled Carbon Nanotube-Based Optical Biosensors, Eric M. Hofferber

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

High resolution, long-term monitoring of key biological analytes would improve patient outcomes by providing earlier detection of disease states and improved efficacy of treatment. One class of biosensors that have gained much attention in recent years are optical biosensors. Optical probes are attractive biosensors due to their noninvasive nature of detection, as certain light can pass through tissue, water, and blood. Single walled carbon nanotubes (SWNT) are a specific type of optical biosensor that fluoresce in the near infrared range of the electromagnetic spectrum and offer unparalleled spatial and temporal resolution. SWNT have been applied as biosensors in vitro, …

Development Of An Internet Of Things (Iot) Enabled Novel Wireless Multi Sensor Network For Infield Crop Monitoring, Nipuna Chamara

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Multispectral imaging systems on satellite, aerial, and ground platforms are used commonly to monitor in-field crops in precision agriculture by farmers and researchers. Limited spatial and temporal resolution and weather dependence of the data collection are two main disadvantages of these methods. In-field sensor networks can continuously monitor environmental and plant physiological parameters by leveraging low-power computation and long-range communication technologies. We built and tested a novel sensor network equipped with soil moisture, multispectral and RGB imaging sensors in an experimental soybean field at Eastern Nebraska Research and Extension Center, NE, USA. 10 down-looking and 1 up-looking sensor node were …

Design, Development, And Field Testing A Visnir Integrated Multi-Sensing Soil Penetrometer, Nuwan K. Wijewardane

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

The research community in soil science and agriculture lacks a cost-effective and rapid technology for in situ, high resolution vertical soil sensing. Visible and near infra-red (VisNIR) technology has the potential to be used for such sensor development due to its ability to derive multiple soil properties rapidly using a single spectrum. Such efforts must, however, overcome a few challenges: (i) a dry ground soil spectral library that can be used to predict the target soil properties accurately, (ii) a robust design which can acquire high quality VisNIR spectra of soil, (iii) an effective method that can link field intact …

Predictive Modeling Of Fate And Transport Of Three Prevalent Contaminants In Midwest Agroecosystem Surface Waters: Nitrate-N, Atrazine, And Escherichia Coli, Samuel Hansen

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

The majority of streams and rivers in the United States (U.S.) are ecologically impaired, or threatened by anthropogenic stressors. Recent reports have found atrazine in drinking water to be associated with increased birth defects and incidences of Non-Hodgkin’s Lymphoma, with higher levels of significance from exposure to both atrazine and nitrate-N. In contrast, recent illnesses from E. coli contaminating vegetables that originated from irrigation water has increased awareness of identifying sources of E. coli entering irrigation reservoirs.

Methods to accurately predict atrazine and E. coli occurrence and potential sources in waterways continue to limit the identifying appropriate and effective prevention …

Using A Vnir Spectral Library To Model Soil Carbon And Total Nitrogen Content, Nuwan K. Wijewardane

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

n-situ soil sensor systems based on visible and near infrared spectroscopy is not yet been effectively used due to inadequate studies to utilize legacy spectral libraries under the field conditions. The performance of such systems is significantly affected by spectral discrepancies created by sample intactness and library differences. In this study, four objectives were devised to obtain directives to address these issues. The first objective was to calibrate and evaluate VNIR models statistically and computationally (i.e. computing resource requirement), using four modeling techniques namely: Partial least squares regression (PLS), Artificial neural networks (ANN), Random forests (RF) and Support vector regression …

Zein: Novel Natural Polymer For Nanoparticle- And Film-Mediated Gene Delivery, Jessica D. Taylor

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Gene delivery, the introduction of DNA into cells, is applicable to gene therapy, DNA vaccination, functional genomics and diagnostics, tissue engineering, and drug-eluting medical devices. Particulates incorporating DNA are promising vehicles for gene delivery and overcome some of the barriers that hinder successful gene transfer, with the ability to protect DNA and provide for controlled, localized, and sustained release and transfection. Furthermore, innovative new gene delivery strategies that incorporate DNA particulates or complexes within films or coatings for devices and scaffolds could further provide for controlled and sustained transfection at the site of implant. Zein, a hydrophobic protein from corn, …

Dynamics Of Depression Storage During Sprinkler Irrigation And Precipitation Events, Michael B. Mckinney

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Surface depression storage (D_s) is the volume of precipitation excess which is stored by surface microrelief features of soils. The volume of water stored in surface depressions when precipitation rate exceeds infiltration rate reduces the amount of runoff generated. Because Ds is dependent on soil microrelief, land slope, and crop residue, tillage and management practices can have a considerable impact on the magnitude of this value.

When modeling irrigation systems and surface hydrology, depression storage is often treated as a static abstraction, meaning that maximum storage volume must be filled before runoff occurs. However, several researchers have documented …

Chemical Modification Of Polysaccharides Using Reactive Extrusion, Pratik Bhandari

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

The objective of this dissertation was to study the use of reactive extrusion for the chemical modifications of starch and cellulose. A carboxymethyl derivative of starch and carboxymethyl and acetate derivatives of cellulose were prepared using reactive extrusion.

Carboxymethyl starch with rapid swelling properties in water was prepared using reactive extrusion. This was achieved by controlling the gelatinization and through the use of NaOH by controlling the water/ethanol ratio. The effects of NaOH, H₂O, temperature, ethanol, sodium mono chloro acetate, sodium tripolyphosphate, citric acid, epichlorohydrin and extruder screw configuration on the degree of substitution of carboxymethyl starch were …

The Economics And Logistics Of The Dual Harvest Of Grain And Biomass In A Single-Pass, Matthew T. Wold

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Significant interest has developed in using cellulosic resources, especially crop residues, to create biofuels. Collecting these residues in a single-pass of the harvester across the field has the potential to be a low cost option. Two models have been developed; the first characterizes the in-field logistics of single-pass crop residue collection, the second the economics. These models allow the user to easily examine a wide variety of both grain-only and single-pass residue collection harvest cases. A variety of possible residue collection cases have been examined, and their effects both on harvester field capacity and harvest cost compared to grain-only harvest …

Extrusion And Alkali Extrusion Of Corn Stover To Improve Enzyme Saccharification, Shujing Zhang

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Biomass pretreatment constitutes an important part in the whole process of bioethanol production. The main goals of pretreatment include improving cellulose accessibility to enzyme, enhancing sugar yields from hemicellulose, achieving low capital and energy costs, as well as low sugar degradation and low chemical requirements. Extrusion, as a continuous and high throughput pretreatment method, requires much less chemical compared to traditional alkali pretreatment. In this research, twin-screw extrusion was evaluated for its effect with regard to promoting sugar yields from corn stover. Also, the underlying factors contributing to this improvement were examined. It was found that extrusion with no chemicals …

Identifying Changes In Climatic Trends And The Fingerprints Of Landuse And Landcover Changes In The High Plains Of The Usa, Denis Mutiibwa

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Human activities such as conversion of natural ecosystem to croplands and urban-centers, deforestation and afforestation impact biophysical properties of land surface such as albedo, energy balance, and surface roughness. Alterations in these properties affect the heat and moisture exchanges between the land surface and atmospheric boundary layer. The objectives of this research were; (i) to quantitatively identify the High plains’ regional climate change in temperatures over the period 1895 to 2006, (ii) detect the signatures of anthropogenic forcing of LULC changes on the regional climate change of the High Plains, and (iii) examine the trends in evolving regional latent heat …

Analysis Of Site-Specific Adjustment Applied To On-The-Go Soil Sensing Data For Agronomic Use, Allison K. Jonjak

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Successful variable-rate applications of agricultural inputs such as lime rely on the quality of input data. Systematic grid soil sampling is the most common method used for creating variable rate prescription maps. The insufficient number of point measurements usually obtained using this method has been primarily responsible for the typical inaccuracies seen in lime prescription maps. To increase sampling density, on-the-go sensing technology was developed for the mapping of soil pH and other relevant attributes. In this study, five fields in eastern Nebraska were mapped using both on-thego sensing technology and systematic grid sampling. Ten calibration points per field were …

Nutrient Runoff Following Manure Application, Chance Thayer

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

A field study was completed to measure the effects of varying flow rate on nutrient transport following the application of varying amounts of beef cattle manure to plots containing either no-residue or a wheat residue cover. Beef cattle manure was applied and incorporated into the soil in May 2010 to meet zero, one, two, four or eight year corn phosphorus requirements. Simulated rainfall events were applied in June and July 2010. The presence of a crop residue cover significantly increased the transport of dissolved phosphorus, total phosphorus, NO₃-N, NH₄-N, and total nitrogen in runoff but decreased …

Development Of An Integrated Soil Properties Mapping System, Rajveer S. Dhillon

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

One of the main goals of precision agriculture (PA) is to define spatial variability in soil properties within an agricultural field to make decisions that can maximize profitability and reduce negative environmental impact. Various soil sensor systems have been developed over the years to map soil properties on-the-go. In this study, an Integrated Soil Mapping System (ISMS) was developed to predict soil water content, soil organic matter, and soil mechanical resistance on-the-go using a capacitance moisture sensor, an optical sensor, and a load cell sensor respectively. These sensors were mounted on the ISMS for acquiring three different data layers at …

Testing Fuel Efficiency Of Tractors With Both Continuously Variable And Standard Geared Transmissions, Christopher N. Howard

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

A John Deere 8295R IVT tractor with a continuously variable transmission (CVT) and a John Deere 8295R PowerShift (PST) tractor (Waterloo, Iowa) with a standard geared transmission (GT) were tested for fuel consumption at three different travel speeds with six different load levels applied per speed. The JD 8295R PST tractor was tested both at full throttle (FT) and shifted up two gears and throttled back (SUTB) to achieve the same travel speed as at full throttle conditions. The three speeds tested corresponded to the maximum speeds achieved in 6th, 8th and 10th gear for the JD 8295R PST tractor …