Engineering Commons^™

Semi-Automated Dental Cast Analysis Software, Mathew Thomas

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Dental casts have been used extensively to study almost all aspects of the human dentition. These aspects varied from the study of tooth form and morphology, inheritance and genetics, growth and development, occlusion, arch alignment and crowding to mathematical determination of dental arch form.

The aim of this project was to develop a tool to semi-automate the measurement of dental casts that would be precise, accurate and efficient. Measurements include tooth widths, arch lengths and widths, angle of rotation and crown area for each tooth.

The task was divided into two different parts: first, the development of semi-automatic software to …

A Computational Tool For Biomolecular Structure Analysis Based On Chemical And Enzymatic Modification Of Native Proteins, Deacon John Sweeney

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Chemical and enzymatic modification of proteins is a well-established treatment technique for probing the conformational properties of these macromolecules. Investigators have recently extended the approach to probe many sites on a protein's structure in parallel manner, such that conformational properties of a target protein can be inferred. The modern approach uses mass spectrometry to quantify reactant loss and product formation. Rigorous analysis is challenging due to the high volume of mass spectrometric data that must be processed and interpreted.

An extensively interactive software suite has been developed to assist various aspects of the analytical protocol. The software offers a variety …

Cervical Spine Biomechanical Behavior And Injury, Mbulelo T. Makola

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A finite element model of the cervical spine including the C2 through C7 levels was developed in order to study the behavior of the cervical spine region. The model was validated in flexion extension, bending, and rotational load scenarios. The model was found to represent the biomechanical behavior of the cervical spine. The validated cervical spine finite element model was used to study spinal injury and disease processes. The model provided qualitative estimates of load carrying and stress distribution as well as range of motion.

The Molecular Basis Of The Interaction Between The Coxsackievirus And Adenovirus Receptor (Car) And Magi-1, Abimbola Olayinka Kolawole

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A major factor in virus entry into cells is localization and abundance of the primary receptor. The Coxsackievirus and adenovirus receptor (CAR) is the primary receptor for group B coxsackievirus and many serotypes of adenovirus. In most epithelia, a seven exon isoform of CAR (CAR^Ex7) is exclusively localized at the basolateral surface where it behaves as a homophilic adhesion protein and is inaccessible for viral infection. However, in well-differentiated human airway epithelia, we recently discovered an alternatively spliced, low abundance isoform of CAR (CAR^Ex8) that is apically localized where it may initiate apical viral infection. The …

The Response Of Pseudomonas Aeruginosa Biofilm To The Presence Of A Glass Polyalkenoate Cement Formulated From A Silver Containing Glass, A. Coughlan, M. P. Ryan, N. M. Cummins, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

No abstract provided.

Influence Of Tissue Absorption And Scattering On Diffuse Correlation Spectroscopy Blood Flow Measurements, Daniel Irwin

University of Kentucky Master's Theses

This investigation evaluates the influences of optical property assumptions on nearinfrared diffuse correlation spectroscopy (DCS) flow index measurements. Independent variation is induced in optical properties, absorption coefficient (μ_a) and reduced scattering coefficient (μ_s’), of liquid phantoms with concurrent measurements of flow indices. A hybrid instrument is incorporated consisting of a dual-wavelength (785 and 830 nm) DCS flow device to obtain flow indices and a frequency-domain tissue-oximeter for optical properties. Flow indices are calculated with measured μ_a and μ_s’ or assumed constant μ_a and μ_s’. Inaccurate μ_s’ assumptions produced …

Biocomposites Developed Using Water-Plasticized Wheat Gluten As Matrix And Jute Fibers As Reinforcement, Narendra Reddy, Yiqi Yang

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Biocomposites developed from wheat gluten using water without any chemicals as plasticizer and jute fibers as reinforcement have much better flexural and tensile properties than similar polypropylene composites reinforced with jute fibers. Wheat gluten is an inexpensive and abundant co-product derived from renewable resources and is biodegradable but non-thermoplastic. Previous attempts at developing biocomposites from wheat gluten have used plasticizers such as glycerol or chemical modifications to make gluten thermoplastic. However, plasticizers have a considerably negative effect on the mechanical properties of the composites and chemical modifications make wheat gluten less biodegradable, expensive and/or environmentally unfriendly. In the research reported, …

Corn Seed Spacing Uniformity As Affected By Seed Tube Condition, Michael F. Kocher, John M. Coleman, John A. Smith, Stephen D. Kachman

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Variation in corn seed spacing from a John Deere MaxEmerge^TM Plus Vacumeter planter was evaluated on the University of Nebraska Planter Test Stand in a laboratory setting for two seed tube conditions (new or worn) with two examples of corn seed shape (round or flat). Seed spacing uniformity was measured using three seed spacing uniformity parameters: Coefficient of Precision (CP3), ISO Multiples index, and ISO Miss index.

Differences were detected in all three seed spacing uniformity parameters due to the seed tube condition. The new seed tubes had better seed spacing uniformity than the worn seed tubes, within each …

Spatial Variability Of Field Machinery Use And Efficiency, Viacheslav I. Adamchuk, Robert Grisso, Michael F. Kocher

Department of Agricultural and Biological Systems Engineering: Faculty Publications

In site-specific crop management, It is a common practice to log the geographic coordinates of agricultural machinery measured using a global satellite navigation system (GNSS) such as the global positioning system (GPS). Yield, fertilizer application, and seed placement maps provide useful data for making agronomic decisions. However, the travel path itself reveals valuable information about machinery performance. Often, during field operations, odd field shapes, obstacles, or contour farming will require operators to increase the complexity of the machinery maneuvering. This usually reduces field efficiency. This chapter presents a methodology to parameterize the spatially variable characteristics of traffic patterns, and to …

Completely Biodegradable Soyprotein–Jute Biocomposites Developed Using Water Without Any Chemicals As Plasticizer, Narendra Reddy, Yiqi Yang

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Soyprotein–jute fiber composites developed using water without any chemicals as the plasticizer show much better flexural and tensile properties than polypropylene–jute composites. Co-products of soybean processing such as soy oil, soyprotein concentrate and soy protein isolates are inexpensive, abundantly available and are renewable resources that have been extensively studied as potential matrix materials to develop biodegradable composites. However, previous attempts on developing soy-based composites have either chemically modified the co-products or used plasticizers such as glycerol. Chemical modifications make the composites expensive and less environmentally friendly and plasticizers decrease the properties of the composites. In this research, soyprotein composites reinforced …

Verifying Power Claims Of High‐Power Agricultural Tractors Without A Pto To Sell In Nebraska, Michael F. Kocher, Viacheslav Adamchuk, John A. Smith, Roger M. Hoy

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Nebraska law requires the Nebraska Tractor Test Board of Engineers to compare results of the tests of an agricultural tractor model with the manufacturer's claims regarding power, fuel use, and other performance ratings in order to recommend a permit to sell that tractor model in the state. PTO tests are conducted to verify the manufacturer's PTO power and fuel claims for tractor models. In recent years, several tractor manufacturers have been producing models of large tractors either without a PTO or with a PTO not capable of transmitting the full engine power and, therefore, have chosen to advertise engine power. …

Evaluation Of Soil Salinity Leaching Requirement Guidelines, John Letey, Glenn J. Hoffman, Jan W. Hopmans, Stephen R. Grattan, Donald Louis Suarez, Dennis L. Corwin, Jim D. Oster, Laosheng Wu, Christopher Amrhein

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Water for irrigation is a major limitation to agricultural production in many parts of the world. Use of waters with elevated levels of salinity is one likely option to meet the supply of increased demands. The sources of these waters include drainage water generated by irrigated agriculture, municipal wastewater, and poor quality groundwater. Soil salinity leaching requirements that were established several decades ago were based on steady-state conditions. Recently transient-state models have been developed that potentially can more correctly predict the dynamics of the chemical–physical–biological interactions in an agricultural system. The University of California Center for Water Resources appointed a …

Comparison Of Subsurface And Surface Runoff Phosphorus Transport Rates In Alluvial Floodplains, Aaron R. Mittelstet, Derek M. Heeren, Garey A. Fox, Daniel E. Storm, Michael J. White, Ronald B. Miller

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Phosphorus (P) loading to streams can occur by both surface runoff and subsurface transport, with subsurface P transport often assumed negligible. Groundwater P concentrations in alluvial aquifers can be significant, especially in preferential flow paths (PFPs). The objectives of this research were to quantify subsurface P transport rates at two sites in northeastern Oklahoma and to compare them with surface runoff P transport rates derived from a hydrologic model, the Pasture Phosphorus Management Calculator (PPM Plus). Ozark ecoregion study sites were adjacent to the Barren Fork Creek and Honey Creek in northeastern OK, USA. Each site, instrumented with 24 observation …

Development Of Deficit Irrigation Strategies For Corn Using A Yield Ratio Model, Derek M. Heeren, Todd P. Trooien, Hal D. Werner, Norman L. Klocke

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Competition for water is increasing while a growing world population requires more food production. It is critical to develop and implement efficient deficit irrigation strategies and to predict the impacts of deficit irrigation on yield. South Dakota State University (SDSU) Management Software, which simulates evapotranspiration and soil water contents, was originally designed as an on-farm decision support system capable of fully automating center pivot irrigation. A simple yield model was developed for the software in order to extend its use for evaluating deficit irrigation strategies. Yield ratio (i.e., actual yield/potential yield) was predicted based on a normalized transpiration ratio (i.e., …

Flow And Transport Experiments For A Streambank Seep Originating From A Preferential Flow Pathway, Garey A. Fox, Derek M. Heeren, Ronald B. Miller, Aaron R. Mittelstet, Daniel E. Storm

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Streambank seeps commonly originate from localized heterogeneity or preferential flow pathways (PFPs) in riparian floodplains. However, limited field data have been reported on ground water seep flows and solute transport to seeps from PFPs. The objective of this research was to build upon previous floodplain-scale investigations of PFPs by analyzing seep discharge and transport characteristics through a single PFP. An important research question was whether this PFP could be conceptualized as a homogeneous, one-dimensional flow path. Streambank seep discharge measurements were obtained by inducing a hydraulic head in a trench injection system. Also, co-injection of Rhodamine WT (RhWT) and a …

In Vivo Magnetic Resonance Elastography Of Mesenchymally Derived Constructs, Shadi F. Othman, Evan T. Curtis, Huihui Xu

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The multidisciplinary field of tissue engineering (TE) aims to create biological substitutes to restore, maintain, or enhance the function of tissue or whole organs, in which the mechanical properties of replacements are critical to their structure and function. Several techniques have been investigated for measuring the mechanical properties of developing tissues and organs; however, current methods are destructive. The goal of this work is to apply high resolution Magnetic Resonance Elastography (μMRE) technique with 100 μm in-plane resolution to address a critical problem in TE: nondestructive monitoring and characterization of growing mesenchymal stem cells (MSCs)-based tissue engineered constructs. In this …

Effect Of Flow Gradient, Roi Size And Random Scatterer Movement During Speckle Size Estimation Based Blood Flow Measurement, Tiantian Xu, Greg Bashford

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Conventional blood flow velocity measurement using ultrasound is capable of resolving the axial component (i.e., that aligned with the ultrasound propagation direction) of the blood flow velocity vector. However, these Doppler-based methods are incapable of detecting blood flow in the direction normal to the ultrasound beam. An algorithm which measures the lateral blood flow velocity using speckle size change with scan velocity was developed in our previous studies. This method uses the apparent speckle size change that occurs when scatterers are moving relative to the spatial rate of A-line acquisition. Our previous results showed that the estimation error of this …

Using Thermally Coupled Reactive Distillation Columns In Biodiesel Production, Nghi Nguyen, Yaşar Demirel

Yaşar Demirel Publications

Production of ethyl dodecanoate (biodiesel) using lauric acid and methanol with a solid acid catalyst of sulfated zirconia is studied by using two distillation sequences. In the first sequence, the methanol recovery column follows the reactive distillation column. In the second sequence, the reactive distillation and methanol recovery columns are thermally coupled. Thermally coupled distillation sequences may consume less energy by allowing interconnecting vapor and liquid streams between the two columns to elminate reboiler or condenser or both. Here we study the thermally coupled side-stripper reactive distillation and eliminate the condenser of the reactive distillation column. Both the sequences are …

Energy And Climate Implications For Agricultural Nutrient Use Efficiency, Adam J. Liska, Richard K. Perrin

Adam Liska Papers

Energy and climate change are beginning to dominate the global political agenda and will drive policy formation that will shape the future of agriculture. Energy issues threaten national security and economic stability, as well as access to low-cost nutrient inputs for agriculture. Climate change has the potential to cause serious disruption to agricultural productivity. Paradoxically, nutrient use in agriculture to increase crop yields has the potential to negatively impact climate. This chapter will discuss recent and future energy and climate trends, the relationships between agricultural nutrient use efficiency and biofuels, and how global land limitations will shape agriculture in the …

Effect Of Distillers Grains Moisture And Inclusion Level In Livestock Diets On Greenhouse Gas Emissions In The Corn-Ethanol-Livestock Life Cycle, Virgil R. Bremer, Andrea K. Watson, Adam J. Liska, Galen Erickson, Kenneth Cassman, Kathryn J. Hanford, Terry Klopfenstein

Adam Liska Papers

A model was previously developed (Biofuel Energy Systems Simulator; www. bess.unl.edu) to predict greenhouse gas (GHG) emissions and net energy yield when ethanol is produced from corn. The model also predicts feedlot cattle, dairy cattle, and swine performance and feed replacement value of ethanol coproducts. Updated equations that predict performance of feedlot cattle fed 0 to 40% of dietary DM as corn wet (WDGS), modified (MDGS), or dry (DDGS) distillers grains plus solubles replacing dry-rolled and high-moisture corn were developed and incorporated into the model. Equations were derived from pen-level performance for 20 finishing studies evaluating WDGS, 4 evaluating MDGS, …

Fus Transgenic Rats Develop The Phenotypes Of Amyotrophic Lateral Sclerosis And Frontotemporal Lobar Degeneration, Cao Huang, Hongxia Zhou, Jianbin Tong, Han Chen, Yong-Jian Liu, Dian Wang, Xiaotao Wei, Xugang Xia

Nebraska Center for Biotechnology: Faculty and Staff Publications

Fused in Sarcoma (FUS) proteinopathy is a feature of frontotemporal lobar dementia (FTLD), and mutation of the fus gene segregates with FTLD and amyotrophic lateral sclerosis (ALS). To study the consequences of mutation in the fus gene, we created transgenic rats expressing the human fus gene with or without mutation. Overexpression of a mutant (R521C substitution), but not normal, human FUS induced progressive paralysis resembling ALS. Mutant FUS transgenic rats developed progressive paralysis secondary to degeneration of motor axons and displayed a substantial loss of neurons in the cortex and hippocampus. This neuronal loss was accompanied by ubiquitin aggregation and …

Comparative Manufacture And Cell-Based Delivery Of Antiretroviral Nanoformulations, Shantanu Balkundi, Ari S. Nowacek, Ram S. Veerubhotla, Han Chen, Andrea Martinez-Skinner, Upal Roy, R. Lee Mosley, Georgette Kanmogne, Xinming Liu, Alexander V. Kabanov, Tatiana Bronich, Joellyn Mcmillan, Howard E. Gendelman

Nebraska Center for Biotechnology: Faculty and Staff Publications

Nanoformulations of crystalline indinavir, ritonavir, atazanavir, and efavirenz were manufactured by wet milling, homogenization or sonication with a variety of excipients. The chemical, biological, immune, virological, and toxicological properties of these formulations were compared using an established monocyte-derived macrophage scoring indicator system. Measurements of drug uptake, retention, release, and antiretroviral activity demonstrated differences amongst preparation methods. Interestingly, for drug cell targeting and antiretroviral responses the most significant difference among the particles was the drug itself. We posit that the choice of drug and formulation composition may ultimately affect clinical utility.

High Temperature Dilute Acid Pretreatment Of Coastal Bermuda Grass For Enzymatic Hydrolysis, Arthur P. Redding, Ziyu Wang, Deepak R. Keshwani, Jay J. Cheng

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Dilute sulfuric acid was used to pretreat coastal Bermuda grass at high temperature prior to enzymatic hydrolysis. After both pretreatment and enzymatic hydrolysis processes, the highest yield of total sugars (combined xylose and glucose) was 97% of the theoretical value. The prehydrolyzate liquor was analyzed for inhibitory compounds (furfural, hydroxymethylfurfural (HMF)) in order to assess potential risk for inhibition during the following fermentation. Accounting for the formation of the inhibitory compounds, a pretreatment with 1.2% acid at 140 °C for 30 min with a total sugar yield of 94% of the theoretical value may be more favorable for fermentation. From …

Bone Tissue Quality Determination Of Mice Through A Novel Reference Point Indentation Technique, Matin Lendhey

Dissertations and Theses

"Bone strength deteriorates with age; which increases the susceptibility to fracture. Current clinical techniques for the estimation of bone strength are largely Bone Mineral Density (BMD) based. However, toughness, which is the ability to resist crack growth, plays a critical role in bones‟ fracture resistance. Traditionally, toughness measurements involve large samples, obviating their use clinically. Recent data suggest that a reference point indentation approach provides a novel, localized measure of toughness from whole bones. In the current research, we evaluated the sensitivity of this method to discriminate small known differences in fracture toughness that exist between inbred mouse strains with …

Development Of An Approach To Increase Drug Uptake To Bone Tumors Using Non-Invasive Mechanical Loading, Paolo E. Palacio

Dissertations and Theses

This thesis develops an approach to enhance drug delivery to bone tumors by implementing a non-invasive mechanical loading technique. An imaging protocol that characterizes the load-enhanced drug uptake is also presented. The long-term goal of this work is to develop a clinical protocol that enhances the delivery of therapeutic agents to bone tumors by utilizing load-bearing activity. This easy-to-implement approach could help increase drug uptake into the tumor interstitial fluid space as well as into tumor cells, thereby enhancing a drug's clinical effect while decreasing systemic drug dosage and unwanted side effects. This thesis details the process used to grow …

Effects Of Estrogen Loss On The Vascular Porosity In Rat Cortical Bone, Jessica D Levy

Dissertations and Theses

"Osteoporosis is a skeletal disease that currently affects 10 million Americans, and is characterized by low bone mass and increased skeletal fragility (National Osteoporosis Foundation, 2011). Estrogen loss, which begins during menopause, is the leading cause of osteoporosis in women. Recent research has focused on changes in cortical bone microporosity due to estrogen loss, which is important for bone health; load-induced interstitial fluid flow within the lacunar-canalicular porosity surrounding osteocytes is thought to play an important role in bone maintenance, while the vascular porosity provides a pressure relaxation mechanism for the fluid flow in the lacunar-canalicular porosity. Recent high-resolution micro-CT …

Transport Of Antibodies And Nanoparticles Across An In Vitro Blood-Brain Barrier, Lin Zhang

Dissertations and Theses

"The blood-brain barrier (BBB) is a dynamic interface between the blood circulation and the central nervous system (CNS). While it serves as a selective barrier to water and solutes to prevent the blood-borne toxins from entering into the brain tissue, it hinders the drug delivery to the CNS for the treatment of brain diseases. Recently therapeutic antibodies and a variety of drug-loaded nanoparticles (NPs) have been widely used to treat CNS disorders such as brain tumors, Alzheimer's disease and Parkinson's disease. To improve brain delivery efficacy of antibodies and NPs, it is necessary to quantify their transport parameters across the …

Evaluation Of A Novel Self-Assembled Nanocoating In Promoting Bone On-Growth And Apposition On Metal, Hani Ghazi

Dissertations and Theses

"Loosening of metal is the leading cause of clinical failures of orthopedic surgeries. A novel coating of self-assembled monolayer of phosphonate molecules (SAMP) that chemically enhances metallic surfaces by covalently bonding to their naturally occurring oxidized surfaces has been developed.1 The SAMP coating is chemically stable, and its in-vitro results showed that it promotes cell proliferation, osteoblast adhesion and enhances biological attachment to metal surfaces.1 The purpose of this study is to establish the efficacy of this novel chemical surface treatment in improving the fixation of metallic implants in both cortical and cancellous bone over a conventional untreated implant. We …

Proteomic Analysis Of Human Mesenchymal Stem Cell Aging During Serial Sub-Culture, Pawan Kc

Dissertations and Theses

"Human mesenchymal stem cells (hMSCs) hold great potential for clinical applications in regenerative medicine. However, hMSCs occur at a very low frequency in bone marrow so the clinical use as cellular therapeutics requires suitable techniques for isolation and expansion. Furthermore, these cells can be expanded in vitro for only limited passage numbers before they reach a senescent state. Previous studies have shown that long term culture of hMSCs results in the decrease in proliferation rates, changes in genomic expressions, increase in cell sizes, and other morphological changes. Currently the mechanisms of hMSC aging and biomarkers associated with it have not …

Role Of Hydrodynamic Behavior Of Dna Molecules In Dielectrophoretic Polarization Under The Action Of An Electric Field, Hui Zhao

Mechanical Engineering Faculty Research

A continuum model is developed to predict the dielectrophoretic polarizability of coiled DNA molecules under the action of an alternating current electric field. The model approximates the coiled DNA molecule as a charged porous spherical particle. The model explains the discrepancies among scaling laws of polarizability of different-sized DNA molecules with contour length and such discrepancies are attributed to different hydrodynamic behavior. With zero or one fitting parameter, theoretical predictions are in good agreement with various experimental data, even though in experiments there are some uncertainties in regard to certain parameters.