Digital Commons Network^™

The Role Of Amp-Activated Protein Kinase (Ampk) In Hypoxic Chemotransduction By The Carotid Body, Heidi Lynn Jordan

Browse all Theses and Dissertations

The carotid bodies are small sensory organs located along the bifurcation of the carotid arteries. They detect changes in blood gases and relay this information to the brain to allow for initiation of appropriate respiratory and cardiovascular responses. A decrease in oxygen (hypoxia) sensed by the carotid body results in an increase in firing of the carotid sinus nerve and ultimately a change in one's breathing pattern. An inability to respond to an acute hypoxic (low oxygen) episode via increased ventilation may result in death or lead to pathological or chronic conditions such as stroke and hypertension (Prabhakar et.al., 2005). …

The Role Of Angiotensin Converting Enzyme (Ace) 2 In A Murine Model Of Insulin Resistance And Albuminuria, Nathan Michael Weir

Browse all Theses and Dissertations

Insulin resistance and kidney disease are intimately linked and both independently tied to dysregulation of the renin angiotensin system (RAS). The purpose of this research was to better investigate Angiotensin Converting Enzyme (ACE) 2 as a possible motif in the pathophysiology of these two disease processes. The project was divided into two parts. Part 1 investigated ACE2 KO mice as a model of albuminuria. Part 2 investigated how the lack of ACE2 enzyme affected glucose homeostasis and subsequent albuminuria.

Part 1: The Role of ACE2 in the Progression of Albuminuria. To determine if global loss of ACE2 leads to spontaneous …

'Omic' Evaluation Of The Region Specific Changes Induced By Non-Cholinergic Diisopropylfluorophosphate (Dfp) Exposure In Fischer 344 Rat Brain, Deirdre A. Mahle

Browse all Theses and Dissertations

Organophosphorous compounds (OPs) are a class of serine esterase inhibitors that have widespread application as pesticides, veterinary pharmaceuticals and chemical warfare agents. Environmental contamination is ubiquitous. The threat of exposure is a concern for both military and civilian populations. Acute inhibition of acetylcholinesterase by OPs triggers a cholinergic crisis that results in muscle flaccidity, paralysis, convulsions and death. At low doses OPs can alter neuronal differentiation, cell signaling, behavior and cognition through unknown mechanisms. An imbalance of reactive oxygen species may be implicated in the adverse effects of OPs. An integrated approach using both metabolomic and transcriptomic techniques was used …

Limitations Of Functional Recovery Of Stretch Reflex Circuitry After Peripheral Nerve Regeneration, Gabrielle Marie Horstman

Browse all Theses and Dissertations

Peripheral nerve regeneration fails to restore complete normal function after surgical repair of severed nerves, and this failure has primarily been attributed to errors in connecting with peripheral targets. However, recent evidence suggests that central deficits remain even after peripheral target reinnervation is largely successful. It has long been established that regeneration fails to restore the stretch reflex despite observation that many of the neural components are intact. Regenerated Ia afferents are largely successful in reinnervating muscle spindles, are capable of encoding stretch, and elicit EPSPs in homonymous motoneurons, while regenerated motor pools are capable of responding to uninjured sources …

Cloudvista: A Framework For Interactive Visual Cluster Exploration Of Big Data In The Cloud, Zhen Li

Browse all Theses and Dissertations

With the development and deployment of ubiquitous information sensing, mobile devices,wireless sensor networks, RFID readers, simulation, and computer generated software logs, big data have become precious resources for scientific study, business intelligence, and national security. As one of the most intuitive and effective analysis methods,visual cluster analysis remains as a significant challenge for big datasets. First, existing visualization models need to be updated to process big data in parallel. Second, processing big data inevitably bring large latency, which conflicts the requirement of interactivity. In this thesis, we develop the CloudVista framework to address the common problems with data reduction methods …

The Role Of Ca2+ In Central Respiratory Control Neurons Of The Locus Coeruleus: Development Of The Chemosensitive Brake, Ann Nicole Imber

Browse all Theses and Dissertations

Chemosensitive LC neurons increase their firing rate in response to increased CO₂ (hypercapnia) in part via inhibition of K⁺ channels. This increase gets smaller during the first two postnatal weeks (neonatal rats aged P3-P16). Alterations of this "accelerating" pathway may account for the developmental changes in the magnitude of the chemosensitive response in LC neurons. Alternatively, Ca²⁺ and Ca²⁺ channels may play a role in the response to hypercapnia, but little is known about the role of Ca²⁺ in central chemosensitivity. Whole cell patch clamp and fluorescence imaging microscopy were used to study a different …

Application Of Auto-Tracking To The Study Of Insect Body Kinematics In Maneuver Flight, Shreyas Vathul Subramanian

Browse all Theses and Dissertations

There is a need to explain the complex phenomena that underlies the seemingly effortless flight modes of the dragonfly (Infra -order Anisoptera). However, measuring the body kinematics during flight is labor intensive. Thus a robust system was developed that automatically tracks and quantifies the body kinematics of a dragonfly during voluntary and escape take-offs, as well as maneuvers. Ultimately, the tool, which was developed using a custom code in C++ using the open source library OpenCV (Open Computer Vision), would be used to analyze bulk samples of high speed videos providing raw images at the rate of approximately 1000 frames …

A Mechanism-Based Model To Describe Gabaa Receptor Trafficking And Benzodiazepine Pharmacoresistance During Status Epilepticus, Elaine Alice Merrill

Browse all Theses and Dissertations

Status epilepticus (SE) is a perplexing pathology involving a sudden and long disruption of the brain's normal electrical activity. The study of relevant cellular processes has been useful in identifying therapeutic targets. As a result, many novel drugs are being studied which target receptor systems involved in neuronal membrane excitability. Yet, the standard treatment for SE remains benzodiazepines (BZs), a class of GABAA agonist drugs. Unfortunately, the targeted receptors undergo a desensitization mechanism via enhanced endocytosis (receptor trafficking), leading to rapidly reduced BZ efficacy (pharmacoresistance) within minutes of seizure onset. A comprehensive understanding of the complex interplay between the anticonvulsant's …

Modeling Carbon Sequestration In Transition Zone To Optimize Storage Potential, Fang Yang

Doctoral Dissertations

"Shallow aquifers are potential candidates for carbon sequestration because of their wide distribution and low injection cost. Injected CO₂ in a shallow region segregates into two zones according to CO₂ phases within the initial reservoir pressure and the maximum bottom hole pressure: gas zone and transition zone. Transition zone is a better option because of favorable CO₂ properties. This work investigated the CO₂ storage potential in transition zone using the compositional simulator CMG-GEM and a design of experiment software iSIGHT. First, it addressed the basic characteristics of CO₂ sequestration in transition zone, and then modeled CO₂ injection with simultaneous water …

A Sociable Humanoid Autonomous Robotic Platform (The Sharp Project): An Evaluation Of The G.E.N.E.S.I.S. Robot As An Interactive Consumer Robotic Platform, Jeffrey J. Rick

Dissertations and Theses @ UNI

The Social Humanoid Autonomous Robotic Platform (SHARP) project is an android project that was created with the intent of making learning about androids and robotics easier for the novice, diverse for the expert, educational in the classroom, and useful in the home or business. The project centers itself on its simplicity, low cost, and expandability. This paper illustrates how the SHARP Project has the potential to be an affordable fit in nearly every modern setting. The introduction of the SHARP project lays the groundwork for people of many ages, incomes, and educational levels to take advantage of robotics technology. The …

The Design And Evaluation Of Wireless Sensor Networks For Applications In Industrial Locations, Hameed Madwar

Dissertations and Theses @ UNI

In manufacturing industries, there exist many applications where Wireless Sensor Networks (WSN's) are integrated to provide wireless solution for the automated manufacturing processes. It is well known that industrial environments characterized by extreme conditions such as high temperature, pressure, and electromagnetic (EM) interference that can affect the performance of the WSN's. The key solution to overcome this performance issue is by monitoring the received Signal Strength Index (RSSI) at the received sensor of the WSN device and track frame error rate of wireless packets.

ZigBee is a wireless sensor network (WSN) standard designed for specific needs of the remote monitoring …

A Comparison Of Near-Infrared And Visible Imaging For Surveillance Applications, Kathryn Nicole Rodhouse

Masters Theses

"A computer vision approach is investigated which has low computational complexity and which compares near-infrared and visible image systems. The target application is a surveillance system for pedestrian and vehicular traffic. Near-infrared light has potential benefits including non-visible illumination requirements. Image-processing and intelligent classification algorithms for monitoring pedestrians are implemented in outdoor and indoor environments with frequent traffic. The image set collected consists of persons walking in the presence of foreground as well as background objects at different times during the day. Image sets with nonperson objects, e.g. bicycles and vehicles, are also considered. The complex, cluttered environments are highly …

Optimization Of Process Planning For Focused Ion Beam Machine In Nano-Manufacturing, Sushrut Shekhar Naik

Masters Theses

"The current revolution witnessed by nanotechnology is facing several challenges such as manufacturing of nano sized devices economically on a large scale. Focused ion beam (FIB) technology is one of the widely used approaches for nano-manufacturing due to its versatile nature. It provides accurate machining and process repeatability and has a range of applications. Major challenges for the current FIB process are the tradeoffs between quality, the processing time, and the long planning time. This research provides a pathway to eliminate the current problems facing nanotechnology. Using MATLAB and the Helios 600 FIB/SEM instrument available, modeling and analyses are carried …

Effects Of Coal Comminution In Relation To Waterjet And Selected Feed Properties, Yaqing Li

Masters Theses

"The necessity to develop a viable alternative to oil means that the development of coal-water fuels (CWF) has become increasingly important. However, the existing methods of comminution to prepare ultrafine particles for CWF are very inefficient. Consequently, a number of novel methods of comminution have been investigated in order to increase the efficiency of the process.

In this research, a new method of comminution using a high-pressure waterjet has been tested to produce ultrafine particle sizes necessary for efficient CWF process. To establish the fundamental performance of the waterjet mill, the influence of the operational pressure, standoff distance, feed size, …

Tracking Articulator Movements Using Orientation Measurements, An Ji, Michael T. Johnson, Jeffrey J. Berry

Speech Pathology and Audiology Faculty Research and Publications

This paper introduces a new method to track articulator movements, specifically jaw position and angle, using 5 degree of freedom (5 DOF) orientation data. The approach uses a quaternion rotation method to accomplish this jaw tracking during speech using a single senor on the mandibular incisor. Data were collected using the NDI Wave Speech Research System for one pilot subject with various speech tasks. The degree of jaw rotation from the proposed approach is compared with traditional geometric calculation. Results show that the quaternion based method is able to describe jaw angle trajectory and gives more accurate and smooth estimation …

Sensing Through The Continent: Towards Monitoring Migratory Birds Using Cellular Sensor Networks, David Anthony, William P. Bennett, Mehmet C. Vuran, Matthew B. Dwyer, Sebastian Elbaum, Anne Lacy, Mike Engels, Walter Wehtje

School of Computing: Conference and Workshop Papers

This paper presents CraneTracker, a novel sensor platform for monitoring migratory birds. The platform is designed to monitor Whooping Cranes, an endangered species that conducts an annual migration of 4, 000 km between southern Texas and north-central Canada. CraneTracker includes a rich set of sensors, a multi-modal radio, and power control circuitry for sustainable, continental-scale information delivery during migration. The need for large-scale connectivity motivates the use of cellular technology in low-cost sensor platforms augmented by a low-power transceiver for ad-hoc connectivity. This platform leads to a new class of cellular sensor networks (CSNs) for time-critical and mobile sensing applications. …

A Low-Cost, Reliable, High-Throughput System For Rodent Behavioral Phenotyping In A Home Cage Environment, Steven A. Parkison, Jay D. Carlson, Tammy R. Chaudoin, Traci A. Hoke, A. Katrin Schenk, Evan H. Goulding, Lance C. Pérez, Stephen J. Bonasera

Department of Electrical and Computer Engineering: Faculty Publications

Inexpensive, high-throughput, low maintenance systems for precise temporal and spatial measurement of mouse home cage behavior (including movement, feeding, and drinking) are required to evaluate products from large scale pharmaceutical design and genetic lesion programs. These measurements are also required to interpret results from more focused behavioral assays. We describe the design and validation of a highly-scalable, reliable mouse home cage behavioral monitoring system modeled on a previously described, one-ofa- kind system [1]. Mouse position was determined by solving static equilibrium equations describing the force and torques acting on the system strain gauges; feeding events were detected by a photobeam …

Systems And Synthetic Biology Of The Vessel Wall, Jennifer Frueh, Nataly Maimari, Ying Lui, Zoltan Kis, Vikram Mehta, Negin Pormehr, Calum Grant, Emmanuel Chalkias, Mika Falck-Hansen, Sandra Bovens, Ryan M. Pedrigi, Taka Homma, Gianfillippo Coppola, Rob Krams

Department of Mechanical and Materials Engineering: Faculty Publications

Atherosclerosis is intimately coupled to blood flow by the presence of predilection sites. The coupling is through mechanotransduction of endothelial cells and approximately 2000 gene are associated with this process. This paper describes a new platform to study and identify new signalling pathways in endothelial cells covering an atherosclerotic plaque. The identified networks are synthesized in primary cells to study their reaction to flow. This synthetic approach might lead to new insights and drug targets.

Usability Assessment Of Two Different Control Modes For The Master Console Of A Laparoscopic Surgical Robot, Xiaoli Zhang, Carl A. Nelson, Dmitry Oleynikov

Department of Mechanical and Materials Engineering: Faculty Publications

The objective of this study is to evaluate potential interface control modes for a compact fourdegree- of-freedom (4-DOF) surgical robot. The goal is to improve robot usability by incorporating a sophisticated haptics-capable interface. Two control modes were developed using a commercially available haptic joystick: (1) a virtually point-constrained interface providing an analog for constrained laparoscopic motion (3-DOF rotation and 1-DOF translation), and (2) an unconstrained Cartesian input interface mapping more directly to the surgical tool tip motions. Subjects (n = 5) successfully performed tissue identification and manipulation tasks in an animal model in point-constrained and unconstrained control modes, respectively, with …

In Vivo Demonstration Of Surgical Task Assistance Using Miniature Robots, Jeff A. Hawks, Jacob Kunowski, Stephen R. Platt

Department of Mechanical and Materials Engineering: Faculty Publications

Laparoscopy is beneficial to patients as measured by less painful recovery and an earlier return to functional health compared to conventional open surgery.However, laparoscopy requires the manipulation of long, slender tools from outside the patient’s body. As a result, laparoscopy generally benefits only patients undergoing relatively simple procedures. An innovative approach to laparoscopy uses miniature in vivo robots that fit entirely inside the abdominal cavity. Our previous work demonstrated that a mobile, wireless robot platform can be successfully operated inside the abdominal cavity with different payloads (biopsy, camera, and physiological sensors). We hope that these robots are a step toward …

The Biological Systems Engineering Program In Nebraska 1895-2011, William Splinter

Department of Agricultural and Biological Systems Engineering: Faculty Publications

4. Preface: How Mechanization Has Impacted Food Production THE PIONEERS WHO ESTABLISHED THIS DEPARTMENT 8 Oscar Van Pelt Stout 10 Charles Russ Richards 12 J. Brownlee Davidson 14 Leon W. Chase FORMER FACULTY AND THEIR CONTRIBUTIONS 18 Laurence Froyd Seaton 20 Ivan D.Wood 22 Oscar W. Sjogren 23 Chauncey W. Smith 25 Elmer E. Brackett 27 Claud Kedzie Shedd 29 Ruby M. Loper 31 Lester F. Larsen 33 Lloyd W. Hurlbut 36 Rollin Schnieder 39 Howard D. Wittmuss 41 Deon Axthelm 46 Paul. E. Fischbach 48 Stuart O. Nelson 51 Kenneth von Bargen 56 John R. Davis 58 Robert W. …

Climate Change Impacts On Streamflow, Water Quality, And Best Management Practices For The Shell And Logan Creek Watersheds In Nebraska, M. W. Van Liew, S. Feng, T. B. Pathak

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Improvements in the management of water, sediment, and nutrients under future climatic conditions are needed to ensure increased crop and livestock production to meet greater global needs and the future availability of water for competing demands and protection against adverse water quality impairments. This study determined the impacts of future climate change scenarios on streamflow, water quality, and best management practices (BMPs) for two watersheds in Nebraska, USA. The Soil and Water Assessment Tool (SWAT) was employed to simulate streamflow, sediment, total nitrogen (N) and total phosphorus (P) from the Shell Creek Watershed near Columbus, Nebraska and the Logan Creek …

Runoff Nutrient Loads As Affected By Residue Cover, Manure Application Rate, And Flow Rate, Chance Thayer, John E. Gilley, Lisa M. Durso, David B. Marx

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Manure is applied to cropland areas with varying surface cover to meet single‐year or multiple‐year crop nutrient requirements. The objectives of this field study were to: (1) examine runoff water quality characteristics following land application of manure to sites with and without wheat residue, (2) compare the water quality impacts of land application of manure to meet 0‐, 1‐, 2‐, 4‐, and 8‐year P‐based requirements for corn, and (3) evaluate the effects of varying runoff rates on runoff nutrient loads. Three 30‐min simulated rainfall events, separated by 24 h intervals, were applied at an intensity of 70 mm h^{‐1 …}

Field Scale Modeling To Estimate Phosphorus And Sediment Load Reductions Using A Newly Developed Graphical User Interface For Soil And Water Assessment Tool, Aaron R. Mittelstet, Erin R. Daly, Daniel E. Storm, Michael J. White, Greg A. Kloxin

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Streams throughout the North Canadian River watershed in northwest Oklahoma, USA have elevated levels of nutrients and sediment. Soil and Water Assessment Tool (SWAT) was used to identify areas that likely contributed disproportionate amounts of Phosphorus (P) and sediment to Lake Overholser, the receiving reservoir at the watershed outlet. These sites were then targeted by the Oklahoma Conservation Commission (OCC) to implement conservation practices, such as conservation tillage and pasture planting as part of a US Environmental Protection Agency Section 319(h) project. Conservation practices were implemented on 238 fields. The objective of this project was to evaluate conservation practice effectiveness …

Whose Water Is It Anyway? Comparing The Water Rights Frameworks Of Arkansas, Oklahoma, Texas, New Mexico, Georgia, Alabama, And Florida, M. D. Smolen, Aaron R. Mittelstet, Bekki Harjo

Department of Agricultural and Biological Systems Engineering: Faculty Publications

In most states surface waters, (streams, lakes, and coastal waters) are owned by the public. On the other hand, ground water may be privately or publicly owned. Because all waters are linked through the hydrologic cycle, and the hydrologic cycle is not confined within any geographic or political boundary, the question of ownership is generally replaced by one of who has the right to manage, divert, use, or sell the water.

Large-Scale On-Farm Implementation Of Soil Moisture-Based Irrigation Management Strategies For Increasing Maize Water Productivity, Suat Irmak, Michael J. Burgert, Haishun Yang, Kenneth G. Cassman, Daniel T. Walters, William R. Rathje, Jose O. Payero, Patricio Grassini, Mark S. Kuzila, Kelly J. Brunkhorst, Dean E. Eisenhauer, William L. Kranz, Brandy Vandewalle, Jennifer M. Rees, Gary L. Zoubek, Charles A. Shapiro, Gregory J. Teichmeier

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Irrigated maize is produced on about 3.5 Mha in the U.S. Great Plains and western Corn Belt. Most irrigation water comes from groundwater. Persistent drought and increased competition for water resources threaten long-term viability of groundwater resources, which motivated our research to develop strategies to increase water productivity without noticeable reduction in maize yield. Results from previous research at the University of Nebraska-Lincoln (UNL) experiment stations in 2005 and 2006 found that it was possible to substantially reduce irrigation amounts and increase irrigation water use efficiency (IWUE) and crop water use efficiency (CWUE) (or crop water productivity) with little or …

P95. In Vivo Loads In The Cervical Spine: A Preliminary Investigation Using A Force-Sensing Implant, Rebecca A. Wachs, Mary Beth M. Grabowsky, Joseph C. Glennon, Eric H. Ledet

Department of Agricultural and Biological Systems Engineering: Faculty Publications

BACKGROUND CONTEXT: It is estimated that up to 80% of the general population will experience at least one significant bout of low back pain in their lifetime. The leading known cause of low back pain is degenerative disc disease (DDD). Many established risk factors for low back pain and DDD are mechanical in nature and are often related to occupational activities, such as poor posture and frequent/heavy lifting. Altered mechanical loading in the spine has been shown to be a potential stimulus for disc degeneration. However, a link between occupational/environmental factors and intervertebral loading has never been demonstrated in vivo. …

Energy Issues Affecting Corn/Soybean Systems: Challenges For Sustainable Production, Douglas L. Karlen, David Archer, Adam Liska, Seth Meyer

Adam Liska Papers

Quantifying energy issues associated with agricultural systems, even for a two-crop corn (Zea mays L.) and soybean (Glycine max [L.] Merr.) rotation, is not a simple task. It becomes even more complicated if the goal is to include all aspects of sustainability (i.e., economic, environmental, and social). This Issue Paper examines energy issues associated with and affecting corn/soybean rotations by first defining the size of the system from both a U.S. and global perspective and then establishing boundaries based on the Farm Bill definition of sustainability. This structured approach is essential to help quantify energy issues within corn/soybean …

Mononuclear Phagocyte Intercellular Crosstalk Facilitates Transmission Of Cell-Targeted Nanoformulated Antiretroviral Drugs To Human Brain Endothelial Cells, Georgette D. Kanmogne, Sangya Singh, Upal Roy, Xinming Liu, Joellyn Mcmillan, Santhi Gorantla, Shantanu Balkundi, Nathan Smith, Yazen Alnouti, Nagsen Gautam, You Zhou, Larisa Poluektova, Alexander Kabanov, Tatiana Bronich, Howard Gendelman

Nebraska Center for Biotechnology: Faculty and Staff Publications

Despite the successes of antiretroviral therapy (ART), HIV-associated neurocognitive disorders remain prevalent in infected people. This is due, in part, to incomplete ART penetration across the blood–brain barrier (BBB) and lymph nodes and to the establishment of viral sanctuaries within the central nervous system. In efforts to improve ART delivery, our laboratories developed a macrophage-carriage system for nanoformulated crystalline ART (nanoART) (atazanavir, ritonavir, indinavir, and efavirenz). We demonstrate that nanoART transfer from mononuclear phagocytes (MP) to human brain microvascular endothelial cells (HBMEC) can be realized through cell-to-cell contacts, which can facilitate drug passage across the BBB. Coculturing of donor MP …

Green Transportation For A Green Earth, Petros J. Katsioloudis, Mildred V. Jones

STEMPS Faculty Publications

Transportation is one of the biggest contributors to the destruction of the environment. Results from environmental research and pursuant governmental regulations are changing the way companies do business and how transportation systems address the future. The Environmental Protection Agency (EPA) has been at the forefront in leading environmental research and instituting policies and regulations to fight the issues impacting the environment. The transportation industry and consumers alike are concerned about the environment, energy resources, efficiencies, and economics. In this article, the authors suggest that it is vital that people promote the protection of the environment and strengthen the laws that …