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Multilayered Plasmonic Covers For Comblike Scattering Response And Optical Tagging, Francesco Monticone, Christos Argyropoulos, Andrea Alu

Department of Electrical and Computer Engineering: Faculty Publications

We discuss the potential of multilayered plasmonic particles to tailor the optical scattering response. The interplay of plasmons localized in thin stacked shells realizes peculiar degenerate cloaking and resonant states occurring at arbitrarily close frequencies. These concepts are applied to realize ultrasharp comblike scattering responses and synthesize staggered, ideally strong superscattering states closely coupled to invisible states. We demonstrate robustness to material losses and to variations in the background medium, properties that make these structures ideal for optical tagging.

Mercury Concentrations In Tropical Resident And Migrant Songbirds On Hispaniola, Jason M. Townsend, Christopher C. Rimmer, Charles T. Driscoll, Kent P. Mcfarland, Eduardo E. Inigo-Elias

Civil and Environmental Engineering - All Scholarship

Despite growing concerns over mercury (Hg) exposure to humans and wildlife on a global scale, little is known about Hg bioaccumulation in the New World tropics. From 2005 to 2011, we monitored Hg concentrations in blood of nine avian species occupying a geographic range of tropical wet broadleaf sites on the island of Hispaniola, including eight passerines (two Nearctic- Neotropical migrant and six resident species) and one top order predatory accipiter. Invertivorous songbirds were further differentiated by foraging guild, with six species of groundforagers and two species of foliage-gleaners. Blood Hg concentrations were orders of magnitude higher in birds sampled …

Long Gap Peripheral Nerve Reconstruction Using Decellularized Nerve Grafts, Srikanth Vasudevan

Bioengineering Dissertations - Archive

Peripheral nerve injuries that arise as a result of trauma, tumor excision or birth can adversely affect the quality of patient life, leading to lifelong disabilities in some cases. Autologous nerve grafts are the clinical "gold standard" for long gap nerve repair, and allogeneic nerve grafts are considered the next best treatment option. Despite having numerous benefits, autologous nerve grafts are associated with limited supply, longer operation time, risk of infection, painful neuroma formation and most importantly, loss of function at the donor site. Allogeneic nerve grafts require transient immunosuppression, which exposes the patients to risks of infection, toxicity and …

Diffuse Optical Tomography To Study The Ischemic Stroke In Rat Models, Zi-Jing Lin

Bioengineering Dissertations - Archive

Stroke, including ischemic stroke and hemorrhagic stroke, is the major leading cause of death in the United States. More than 80 percent of stroke patients are diagnosed with ischemic stroke, which usually results from blockage of artery in the brain by thrombosis or arterial embolism. Animal Models, which permit powerful genetic and molecular approaches, provide an essential tool to study and understand the basic processes and potential therapeutic interventions for this disease. Significant efforts have been made to closely mimic the changes that occur in humans during and after stroke using animal models. Recent development on near infrared (NIR) diffuse …

Kinetics Analyses Of Interactions Between Oncogenic And Tumor Suppressor Proteins By Quantitative High Resolution Microscopy Methods, Shu-Fen Tseng

Bioengineering Dissertations - Archive

DAB2IP is correlated to the risk of aggressive prostate cancer and loss of DAB2IP not only leads to epithelial-to-mesenchymal transition (EMT), but also makes cells radioresistant. These observations support the notion that improved knowledge of DAB2IP involvement in cellular pathways could be of help to cancer therapy. The goal of this work was to enable the study of how DAB2IP and some of its known key molecular partners interact in the cell by a combination of molecular biology techniques and recently reported quantitative fluorescence microscopy methods. The first part of this work was dedicated on investigating the interaction of DAB2IP …

How Atomic Level Interactions Drive Membrane Fusion: Insights From Molecular Dynamics Simulations, Navendu Bhatnagar

Wayne State University Dissertations

This project is focused on identifying the role of key players in the membrane fusion process at the atomic level with the use of molecular dynamics simulations. Membrane fusion of apposed bilayers is one of the most fundamental and frequently occurring biological phenomena in living organisms. It is an essential step in several cellular processes such as neuronal exocytosis, sperm fusion with oocytes and intracellular fusion of organelles to name a few. Membrane fusion is a frequent process in a living organism but is still not fully understood at the atomic level in terms of the role of various factors …

Research Project On Biometrics, Alia Hassan, Ingy Nazif

Papers, Posters, and Presentations

As technology evolves, and our personal details become more and more susceptible to hacking, one of the most important concerns we now have is being sure our phones, computers, networks are secure. We have begun to move on from simple password and motion patterns onto using facial recognition, and other forms of biometric recognition technology to protect our private information. The iPhone 5 for example, now presents features to identify uniquely the owner of the device, in the form of fingerprint detection. So we decided to focus on the topic biometrics for this research paper, which is basically how to …

Biom 4110/6110: The Science Of Medicine (Syllabus), Bradford D. Pendley

Biomedical Engineering Syllabi Archive

Course Description: Integration of fundamental principles from physics, chemistry, biology and mathematics, and applications of these principles to solve problems in medicine.

Occurrence Of Antimicrobials And Antimicrobial Resistance Genes In Beef Cattle Storage Ponds And Swine Treatment Lagoons, Yuping Zhang, Chiqian Zhang, David B. Parker, Daniel D. Snow, Zhi Zhou, Xu Li

Nebraska Water Center: Faculty Publications

Livestock manure treatment and storage structures are potential environmental sources of antimicrobials and antimicrobial resistance genes (ARGs). In this study, the occurrence of antimicrobials and ARGs was investigated in the water and the sludge compartments of beef cattle storage ponds and swine lagoons. Analysis was focused on two families of antimicrobials (sulfonamide and tetracycline) and the corresponding ARGs (sul1, sul2, tetO, tetQ and tetX). Results showed that the pseudo-partitioning coefficients of tetracyclines were higher than those of sulfonamides, suggesting different distributions of these two classes of antimicrobials between water and sludge. The ARGs tested were …

Design And Optimization Of A Thermal Capacitor, Karen Nielson, Jordan Tracy Cox

Undergraduate Honors Capstone Projects

Team Hot Stuff designed a thermal capacitor for Senior Design I at Utah State University. This thermal capacitor is intended for use in the food service industry as a low-cost alternative to chafers. Chafers are platters which use oil burners to keep food warm. The client for this thermal capacitor is Thermal Management Technologies (TMT), a company specializing in thermal science solutions whose mission is “to provide simple, practical thermal science solutions to a wide range of platforms including: Industry, Defense, and Space”¹. The founder and president of TMT, Dr. J. Clair Batty, serves as a mentor for …

Variability Of Extreme Precipitation In Coastal River Basins Of The Southern Mexican Pacific Region, Nancy Perez-Morga, Thomas Kretzschmar, Tereza Cavazos, Stephen V. Smith, Francisco Munoz-Arriola

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Extreme wet and dry years (± 1 standard deviation, respectively), as well as the top 95 percentile (P95) of daily precipitation events, derived from tropical cyclone (TC) and nontropical cyclone (NTC) rainfall, were analyzed in coastal river basins in Southern Oaxaca, Mexico (Río Verde, Río Tehuantepec, and the Southern Coast). The study is based on daily precipitation records from 47 quality-controlled stations for the 1961 to 1990 period and TC data for the Eastern Tropical Pacific (EPAC). The aim of this study was to evaluate extreme (dry and wet) trends in the annual contribution of daily P95 precipitation events and …

Runoff Nutrient Transport As Affected By Land Application Method, Swine Growth Stage, And Runoff Rate, J. E. Gilley, Shannon L. Bartelt-Hunt, S. J. Lamb, X. Li, D. B. Marx, D. D. Snow, D. B. Parker, B. L. Woodbury

Department of Agricultural and Biological Systems Engineering: Faculty Publications

This study was conducted to measure the effects of slurry application method, swine growth stage, and flow rate on runoff nutrient transport. Swine slurry was obtained from production units containing grower pigs, finisher pigs, or sows and gilts. The swine slurry was applied using broadcast, disk, or injection methods at a rate required to meet annual nitrogen requirements for corn. Three 30 min simulated rainfall events, separated by 24 h intervals, were applied to the experimental plots at an intensity of 70 mm h^-1. Inflow was applied at the top of each plot in four successive increments after …

Hourly And Daily Single And Basal Evapotranspiration Crop Coefficients As A Function Of Growing Degree Days, Days After Emergence, Leaf Area Index, Fractional Green Canopy Cover, And Plant Phenology For Soybean, Suat Irmak, Lameck O. Odhiambo, James Specht, Koffi Djaman

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Hourly evapotranspiration (ET) crop coefficients (K_c) are needed to optimize the effectiveness and efficiency of high-frequency micro- and sprinkler irrigation practices involving the application of water multiple times a day. However, not much is known about the daily and seasonal patterns and magnitudes in hourly K_c values for soybean. In addition, locally developed K_c values are necessary for more robust within-season irrigation management, crop ET estimation, and water balance analyses. Hourly and daily Kc functions were developed for soybean in south-central Nebraska through extensive field research. Actual crop evapotranspiration (ET_a) was measured using a …

Transferability Of Jarvis-Type Models Developed And Re-Parameterized For Maize To Estimate Stomatal Resistance Of Soybean: Analyses On Model Calibration, Validation, Performance, Sensitivity, And Elasticity, Denis Mutiibwa, Suat Irmak

Department of Agricultural and Biological Systems Engineering: Faculty Publications

In a previous study by the same authors, a new modified Jarvis model (NMJ-model) was developed, calibrated, and validated to estimate stomatal resistance (rs) for maize canopy on an hourly time step. The NMJ-model’s unique subfunctions, different from the original Jarvis model (J-model), include a photosynthetic photon flux density

(PPFD)-r_s response subfunction developed from field measurements and a new physical term, Aexp(1/LAI), where A is the minimum stomatal resistance and LAI is the green leaf area index, to account for the influence of canopy development on r_s, especially during partial canopy stage in the early season and …

Impact Of Water And Nitrogen Management Strategies On Maize Yield And Water Productivity Indices Under Linear-Move Sprinkler Irrigation, Daran Rudnick, Suat Irmak

Department of Agricultural and Biological Systems Engineering: Faculty Publications

With uncertainty in future irrigation water availability and regulations on nutrient application amounts, experimentally determined effects of “controllable” management strategies such as nitrogen (N), water, and their combination on crop water productivity (CWP, also known as crop water use efficiency) and actual evapotranspiration (ET_a) are essential. The effects of various N application rates (0, 84, 140, 196, and 252 kg ha^-1) under fully irrigated (FIT), limited irrigation (75% FIT), and rainfed conditions on maize (Zea mays L.) yield and various CWP indices were investigated in 2011 and 2012 growing seasons under linear-move sprinkler irrigation in south …

Assessing Climate Change Impacts On Water Balance, Runoff, And Water Quality At The Field Scale For Four Locations In The Heartland, Michael W. Van Liew, Song Feng, T. B. Pathak

Department of Agricultural and Biological Systems Engineering: Faculty Publications

This study employed the Soil and Water Assessment Tool (SWAT) to evaluate the impacts of projected future climate change scenarios on water balance, runoff, sediment, total nitrogen (N), and total phosphorus (P) at the field scale for four locations in the Heartland region: Sioux City (Iowa) and Columbus, Mullen, and Harrison (Nebraska). A conventional two-year corn-soybean rotation was assumed to be grown on each field. All fields were simulated identically in terms of topographic and cover/land management conditions. Model inputs for the fields differed in only

three ways: the forcing conditions for existing and future climatic scenarios (SRES A2, A1B, …

Evapotranspiration And Surface Energy Balance Of A Common Reed-Dominated Riparian System In The Platte River Basin, Central Nebraska, Isa Kabenge, Suat Irmak, John E. Gilley, George E. Meyer, Stevan Z. Knezevic, Timothy J. Arkebauer, Duane Woodward, Milton Moravek

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Quantifying actual evapotranspiration (ET_a) of riparian zones is important for more robust water balance analyses that will enable better planning, managing, and allocating of water resources as well as developing strategies to protect delicate riparian ecosystem functions. The ET_a, sensible heat flux (H), net radiation (R_n), soil heat flux (G), meteorological variables (air temperature, T_a; incoming shortwave radiation, R_s; wind speed, u₃; relative humidity, RH; vapor pressure deficit, VPD; precipitation, etc.), and albedo were measured on an hourly time step, and leaf area index (LAI) and plant height …

Use Of A Surrogate To Evaluate The Impact Of Tillage On The Transport Of Steroid Hormones From Manure-Amended Agricultural Fields, Sagor Biswas, William Kranz, Charles A. Shapiro, Mitiku Mamo, Shannon L. Bartelt-Hunt, Daniel D. Snow, David P. Shelton, David D. Tarkalson, Terry L. Mader, Simon J. Van Donk, Tian C. Zhang

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Beef feedlot manure distributed to row crop production areas is a potential surface water contaminant source of the steroid hormones commonly used in beef cattle production. This article reports on research conducted at the University of Nebraska Haskell Agricultural Laboratory near Concord, Nebraska, in July 2009. Manure, collected from beef feedlot pens, was stockpiled for ten months prior to application to a row crop field. Previous research identified that the detection frequency of steroid hormones in beef manure varies greatly. Thus, a surrogate (17α-ethynylestradiol, EE2) was applied at a rate of 75 g ha^-1 to ensure detectable concentrations in …

Transport Of Steroid Hormones In The Vadose Zone After Land Application Of Beef Cattle Manure, Simon Van Donk, Sagor Biswas, William L. Kranz, Daniel D. Snow, Shannon L. Bartelt-Hunt, Terry L. Mader, Charles A. Shapiro, David P. Shelton, David D. Tarkalson, Tian .. Zhang, Steve Ensley

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Few studies have been conducted to investigate the potential contamination of groundwater from manureborne steroid hormones. The objective of this study was to monitor leaching of steroid hormones at the bottom of 2.4 m deep percolation lysimeters installed in plots treated with beef cattle manure. Soil samples were also collected from surrounding field plots. Treatments consisted of application of manure from two treatment methods (stockpiling and composting) or no manure application. Laboratory analyses of manure, soil, and leachate samples used liquid chromatography and tandem mass spectrometry to identify 17 steroid hormones and metabolites. Progesterone, estrone, β-zearalenol, and 4-androstenedione were detected …

Water Productivity Of Corn And Dry Bean Rotation On Very Fine Sandy Loam Soil In Western Nebraska, William E. Spurgeon, C. Dean Yonts

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Subsurface drip irrigation (SDI) was used to irrigate corn and dry beans in a crop rotation study for four years from 2005 to 2008 to evaluate the accumulative effect of irrigation amount on yield and irrigation water use efficiency (I_WUE). This study was conducted on a very fine sandy loam soil using a short season corn hybrid typical for the area. Four irrigation treatments based on providing a fraction of the estimated crop evapotranspiration (ET_c) were evaluated. The treatments were designed to replace a certain percentage of ET_c and were denoted as I₁₂₅, …

Surface- And Hydrogel-Mediated Delivery Of Nucleic Acid Nanoparticles, Angela K. Pannier, Tatiana Segura

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Gene expression within a cell population can be directly altered through gene delivery approaches. Traditionally for nonviral delivery, plasmids or siRNA molecules, encoding or targeting the gene of interest, are packaged within nanoparticles. These nanoparticles are then delivered to the media surrounding cells seeded onto tissue culture plastic; this technique is termed bolus delivery. Although bolus delivery is widely utilized to screen for efficient delivery vehicles and to study gene function in vitro, this delivery strategy may not result in efficient gene transfer for all cell types or may not identify those delivery vehicles that will be efficient in vivo. …

Avhrr-Ndvi-Based Crop Coefficients For Analyzing Long-Term Trends In Evapotranspiration In Relation To Changing Climate In The U.S. High Plains, Denis Mutiibwa, Suat Irmak

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Studies in regions of extensive irrigation practices have revealed a significant influence of evaporative cooling on regional temperatures as a result of surface energy redistribution during evaporation. In the U.S. High Plains, maximum temperatures during the last quarter of the 20th century have been decreasing. We investigated the trends in evapotranspiration (ET or latent heat) fluxes originating from increasing irrigation practices in the High Plains region from 1981 to 2008. We estimated actual ET (ETc) over the entire High Plains from the spatial crop coefficients (Kc) and spatial reference (potential) ET (ETref). We proposed …

Techniques To Quantify The Size Of Protein Colloids In Amyloid Fiber Formation, Jonathan R. Anson, Chia-Hung Lu, Lingwen Cui, Xiaojing Yang, Shaohua Xu

Biomedical Engineering and Sciences Faculty Publications

A new method for the analysis of protein colloidal diameter has been developed using three existing protein concentration quantification techniques, absorption at 280 nm, colloidal gold assay, and DC protein assay. Protein colloids are formed in the process of aggregation and are thought to be intermediates in protein self-assembly and formation of amyloid fiber. Deposition of the protein fibers in tissues leads to numerous human diseases including Alzheimer’s. Lysozyme was incubated at pH 2.0, 55°C, an environment conducive to amyloid fiber formation. The protein colloids present in the supernatant of the samples after centrifugation were studied over a time course …

Silicon Photonic Devices For Optical Delay Lines And Mid Infrared Applications, Saeed Khan

Electronic Theses and Dissertations

Silicon photonics has been a rapidly growing subfield of integrated optics and optoelectronic in the last decade and is currently considered a mature technology. The main thrust behind the growth is its compatibility with the mature and low-cost microelectronic integrated circuits fabrication process. In recent years, several active and passive photonic devices and circuits have been demonstrated on silicon. Optical delay lines are among important silicon photonic devices, which are essential for a variety of photonic system applications including optical beam-forming for controlling phased-array antennas, optical communication and networking systems and optical coherence tomography. In this thesis, several types of …

Influence Of Task-Role Mental Models On Human Interpretation Of Robot Motion Behavior, Scott Ososky

Electronic Theses and Dissertations

The transition in robotics from tools to teammates has begun. However, the benefit autonomous robots provide will be diminished if human teammates misinterpret robot behaviors. Applying mental model theory as the organizing framework for human understanding of robots, the current empirical study examined the influence of task-role mental models of robots on the interpretation of robot motion behaviors, and the resulting impact on subjective ratings of robots. Observers (N = 120) were exposed to robot behaviors that were either congruent or incongruent with their task-role mental model, by experimental manipulation of preparatory robot task-role information to influence mental models (i.e., …

Systems Geometry: A Methodology For Analyzing Emergent System Of Systems Behaviors, Christina Bouwens

Electronic Theses and Dissertations

Recent advancements in technology have led to the increased use of integrated ‘systems of systems’ (SoS) which link together independently developed and usable capabilities into an integrated system that exhibits new, emergent capabilities. However, the resulting SoS is often not well understood, where secondary and tertiary effects of tying systems together are often unpredictable and present severe consequences. The complexities of the composed system stem not only from system integration, but from a broad range of areas such as the competing objectives of different constituent system stakeholders, mismatched requirements from multiple process models, and architectures and interface approaches that are …

Biomarkers For Brain Disorders Electrochemically Detected By Broderick Probe Microelectrodes/Biosensors, Waqas Saleem, Patricia A. Broderick

Publications and Research

Here, we present results from two independent studies carried out using Neuromolecular Imaging (NMI) with miniature BRODERICK PROBE® biosensors. In the first study, we imaged neurotransmitters and neurochemicals in human epilepsy patients intraoperatively during early and late neurodegeneration. In the second study, we imaged neurotransmitters and neurochemicals in an experimental murine model using animals with and without neurodegeneration caused by Parkinson’s disease (PD). We compared our results derived from animals with lesioned group (PD) with non-lesioned group (non-PD), using the same in vivo NMI paradigm. NMI biotechnology enabled neurotransmitters, neuropeptides and neurochemical imaging of dopamine (DA), serotonin (5-HT), homovanillic acid …

Computational Methods For Comparative Non-Coding Rna Analysis: From Structural Motif Identification To Genome-Wide Functional Classification, Cuncong Zhong

Electronic Theses and Dissertations

Recent advances in biological research point out that many ribonucleic acids (RNAs) are transcribed from the genome to perform a variety of cellular functions, rather than merely acting as information carriers for protein synthesis. These RNAs are usually referred to as the non-coding RNAs (ncRNAs). The versatile regulation mechanisms and functionalities of the ncRNAs contribute to the amazing complexity of the biological system. The ncRNAs perform their biological functions by folding into specific structures. In this case, the comparative study of the ncRNA structures is key to the inference of their molecular and cellular functions. We are especially interested in …

Modeling Learner Mood In Realtime Through Biosensors For Intelligent Tutoring Improvements, Keith Brawner

Electronic Theses and Dissertations

Computer-based instructors, just like their human counterparts, should monitor the emotional and cognitive states of their students in order to adapt instructional technique. Doing so requires a model of student state to be available at run time, but this has historically been difficult. Because people are different, generalized models have not been able to be validated. As a person’s cognitive and affective state vary over time of day and seasonally, individualized models have had differing difficulties. The simultaneous creation and execution of an individualized model, in real time, represents the last option for modeling such cognitive and affective states. This …

Planning And Control Of Swarm Motion As Continua, Hossein Rastgoftar

Electronic Theses and Dissertations

In this thesis, new algorithms for formation control of multi agent systems (MAS) based on continuum mechanics principles will be investigated. For this purpose agents of the MAS are treated as particles in a continuum, evolving in an n-D space, whose desired configuration is required to satisfy an admissible deformation function. Considered is a specific class of mappings that is called homogenous where the Jacobian of the mapping is only a function of time and is not spatially varying. The primary objectives of this thesis are to develop the necessary theory and its validation via simulation on a mobile-agent based …