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A Dose-Response Curve For The Negative Bias Pressure Of An Intrathoracic Pressure Regulator During Cpr, Charles F. Babbs, Demetris Yannopoulos

Weldon School of Biomedical Engineering Faculty Publications

An intrathoracic pressure regulator (ITPR) is a device that can be added to the external end of an endotracheal tube to create controlled negative airway pressure between positive pressure ventilations. The resulting downward bias of the airway pressure baseline promotes increased venous return and enhanced circulation during CPR and also during hypovolemic shock. In the present study we exercised a mathematical model of the human cardiopulmonary system, including airways, lungs, a 4 chambered heart, great vessels, peripheral vascular beds, and the biomechanics of chest compression and recoil, to determine the relationship between systemic perfusion pressure during CPR and the value …

Optimal Control Theory Applied To A Difference Equation Model Of Cardiopulmonary Resuscitation, Eunok Jung, Charles F. Babbs, Suzanne Lenhart, Vladimir A. Protopoescu

Weldon School of Biomedical Engineering Faculty Publications

Objective: To apply the mathematical techniques of optimal control theory (OCT) to a validated model of the human circulation during cardiopulmonary resuscitation (CPR), so as to discover improved waveforms for chest compression and decompression that maximize the systemic perfusion pressure (SPP). Methods: The human circulatory system is represented by seven difference equations, which describe the pressure changes in systemic vascular compartments caused by chest compression. The forcing term is the intrathoracic pressure generated by the external chest compression, which is taken as the “control” variable for the system. The optimum waveform of this forcing pressure as a function of time, …

Perspective On Indicators Of Sustainability For The Gold And Silver Extraction Industry, Jarnes L. Hendrix

Papers in Sustainable Mining

No abstract provided.

Dynamic Voltage Scaling Techniques For Power Efficient Video Decoding, Ben Lee, Eriko Nurvitadhi, Reshma Dixit, Chansu Yu, Myungchul Kim

Electrical and Computer Engineering Faculty Publications

This paper presents a comparison of power-aware video decoding techniques that utilize dynamic voltage scaling (DVS). These techniques reduce the power consumption of a processor by exploiting high frame variability within a video stream. This is done through scaling of the voltage and frequency of the processor during the video decoding process. However, DVS causes frame deadline misses due to inaccuracies in decoding time predictions and granularity of processor settings used. Four techniques were simulated and compared in terms of power consumption, accuracy, and deadline misses. In addition, this paper proposes the frame-data computation aware (FDCA) technique, which is …

Axial Stent Strut Angle Influences Wall Shear Stress After Stent Implantation: Analysis Using 3d Computational Fluid Dynamics Models Of Stent Foreshortening, John F. Ladisa, Lars E. Olson, Douglas Anthony Hettrick, David C. Warltier, Judy R. Kersten, Paul S. Pagel

Biomedical Engineering Faculty Research and Publications

Introduction

The success of vascular stents in the restoration of blood flow is limited by restenosis. Recent data generated from computational fluid dynamics (CFD) models suggest that the vascular geometry created by an implanted stent causes local alterations in wall shear stress (WSS) that are associated with neointimal hyperplasia (NH). Foreshortening is a potential limitation of stent design that may affect stent performance and the rate of restenosis. The angle created between axially aligned stent struts and the principal direction of blood flow varies with the degree to which the stent foreshortens after implantation.

Methods

In the current investigation, we …

Use Of 16s Rrna Gene Terminal Restriction Fragment Analysis To Assess The Impact Of Solids Retention Time On The Bacterial Diversity Of Activated Sludge, Pascal E. Saikaly, Peter George Stroot, Daniel B. Oerther

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Terminal restriction fragment length polymorphism (T-RFLP) analysis of 16S rRNA genes was used to investigate the reproducibility and stability in the bacterial community structure of laboratory-scale sequencing batch bioreactors (SBR) and to assess the impact of solids retention time (SRT) on bacterial diversity. Two experiments were performed. In each experiment two sets of replicate SBRs were operated for a periods of three times the SRT. One set was operated at an SRT of 2 days and another set was operated at an SRT of 8 days. Samples for T-RFLP analysis were collected from the two sets of replicate reactors. HhaI, …

Support For A Delivery Train Based Material Handling Mechanism, Sai P. Boyedapu

Electrical & Computer Engineering Theses & Dissertations

Modeling a delivery train system is more challenging than traditional forklift systems as the delivery train model consists of a tugger, cart and a controller that combine to deliver materials within a manufacturing plant. Also, the decision logic for selection of carts and tuggers, joining of loads to particular delivery trains is more complicated than forklift systems. Simulation software such as Arena, Automod and Flexsim do not provide direct support for modeling delivery train systems.

In this thesis, an object-oriented, platform and language independent model of a delivery train was designed. The model was then implemented as an extension to …

Computational Analysis And Validation Of The Hans Head And Neck Support, Kapil Tyagi

Mechanical & Aerospace Engineering Theses & Dissertations

One of the major causes of racing fatalities is basilar skull fracture from excessive head motions and neck loading in a frontal impact. There are many head/neck restraints available in the market but HANS head and neck support has proved to be the most efficient one in sled testing. This paper evaluates and compares the performance of the HANS device in MAthematical DYnamic MOdel (MADYMO) software with the sled testing. The tests were conducted for the frontal impact motions, with a crash pulse of 45 G's.

The goal of the tests was to evaluate the performance of HANS without the …

An Analysis Of A Finite Element Human Brain In Low Speed Rear Impact Automobile Collision Comparison, Model Development And Study Using Tno Rear Impact Dummy, Mangesh S. Kadam

Mechanical & Aerospace Engineering Theses & Dissertations

According to the National Safety Council, rear-end collisions are the most common types of collisions with approximately two and a half million cases reported every year. Crash tests indicate a change of vehicle velocity of 4km/h (2.5 mph) may produce occupant symptoms. Vehicle damage may not occur until 14-15km/h (8.7 mph) (Davis CG, 1998). Occupants, in rear-end vehicle impacts sustain a motion associated with whiplash, where the head snaps backwards quickly, resulting in linear and/or angular acceleration forces acting on the brain. This angular motion tends to subject the brain to shear deformations from rapid rotation. This study is a …

A Motion Planning Processor On Reconfigurable Hardware, Nuzhet Atay, Burchan Bayazit

All Computer Science and Engineering Research

Motion planning algorithms enable us to find feasible paths for moving objects. These algorithms utilize feasibility checks to differentiate valid paths from invalid ones. Unfortunately, the computationally expensive nature of such checks reduces the effectiveness of motion planning algorithms. However, by using hardware acceleration to speed up the feasibility checks, we can greatly enhance the performance of the motion planning algorithms. Of course, such acceleration is not limited to feasibility checks; other components of motion planning algorithms can also be accelerated using specially designed hardware. A Field Programmable Gate Array (FPGA) is a great platform to support such an acceleration. …

Cgmp Recombinant Fix For Iv And Oral Hemophilia B Therapy, William H. Velander Principal Investigator, Abramson Stephan Lead Investigator, Cooper Julian Lead Investigator, William Dernell Key Person, Mark Manning Lead Investigator, Michael Meagher Lead Investigator, Paul Mohanan Lead Investigator, Timothy Nichols Lead Investigator, Todd Swaanson Key Person, Kevin E. Van Cott

Department of Chemical and Biomolecular Engineering: Funded Proposals

Three specific aims are proposed: Specific Aim # 1. Process engineer and scale-up the recovery and purification of transgenic recombinant human Factor IX. The University of Nebraska-Lincoln Biological Process Development Facility will complete process development and scale-up, and produce clinical grade materials for preclinical studies. The endpoint is a proposed final product specification to help facilitate transfer to current Good Manufacturing Practices compliant production of clinical grade material to support an Investigational New Drug filing with the United States Food and Drug Administration (FDA) leading to clinical trials. Specific Aim #2. Characterize and formulate transgenic recombinant human Factor IX for …

Microbial Quality Of Runoff Following Land Application Of Cattle Manure And Swine Slurry, Jeanette A. Thurston-Enriquez, John E. Gilley, Bahman Eghball

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Concentrations of human health-related microorganisms in runoff from agricultural plots (0.75m x 2m) treated with fresh and aged cattle manure, swine slurry and no manure (control) were determined. Three consecutive simulated rainfall events, producing 35 mm rainfall and separated by 24 h, were carried out for each plot. Fecal indicator (Escherichia coli, enterococci, Clostridium perfringens and coliphage) loads released in rainfall runoff from plots treated with fresh cattle manure, aged cattle manure and swine slurry treatments ranged from 5.52 x 10⁵ to 4.36 x 10⁹, 3.92 x 10⁴ to 4.86 x 10⁸, and 9.63 …

Biophysics Of Cardiopulmonary Resuscitation With Periodic Z-Axis Acceleration Of Abdominal Compression At Aortic Resonant Frequencies, Charles F. Babbs

Weldon School of Biomedical Engineering Faculty Publications

Periodic z-axis acceleration (pGz)-CPR involves oscillating motion of a whole patient in the head-to-foot dimension on a mechanized table. The method is able to sustain blood flow and long-term survival during and after prolonged cardiac arrest in anesthetized pigs. However, the exact mechanism by which circulation of blood is created has remained unknown. Objectives: To explain the hemodynamic mechanism of pGz-CPR and to suggest theoretically useful improvements. Method: Computer modeling using a hybrid analytical-numerical approach, based upon Newton’s second law of motion for fluid columns in the aorta and vena cavae, Ohm’s law for resistive flow through vascular beds, and …

Contrast-Detail Analysis Characterizing Diffuse Optical Fluorescence Tomography Image Reconstruction, Scott C. Davis, Brian W. Pogue, Hamid Dehghani, Keith D. Paulsen

Dartmouth Scholarship

Contrast-detail analysis is used to evaluate the imaging performance of diffuse optical fluorescence tomography (DOFT), characterizing spatial resolution limits, signal-to-noise limits, and the trade-off between object contrast and size. Reconstructed images of fluorescence yield from simulated noisy data were used to determine the contrast-to-noise ratio (CNR). A threshold of CNR=3 was used to approximate a lowest acceptable noise level in the image, as a surrogate measure for human detection of objects. For objects 0.5 cm inside the edge of a simulated tissue region, the smallest diameter that met this criteria was approximately 1.7 mm, regardless of contrast level, and test …

Laser And Led Effects On The Proliferation Rate Of Periodontal Ligament Fibroblasts, Allen J. Job

Loma Linda University Electronic Theses, Dissertations & Projects

PURPOSE: To compare the effectiveness of a Gallium Aluminum Arsenide (GaAlAs) diode laser and a light emitting diode (LED) on periodontal ligament fibroblast cell proliferative rates.

METHODS and MATERIALS: PDLF obtained from freshly extracted permanent teeth were cultured under standard conditions until a subconfluent monolayer was present. The next section took 5 days to complete. On day 1, the initial cell concentration of 700 uL/cm² was plated on 96-well assay plates and placed in a CO₂ incubator at 37° C for 24 hours. On day 2, cell counts were first verified using hemocytometry then were irradiated using an …

Manufacturing Companies And The Information Age In The U.S., Marcos Reynero

Graduate Research Papers

The purpose of this research paper is to analyze the relationship between the amount of indirect labor and value added in manufacturing companies. Companies are moving manufacturing sites overseas in order to reduce cost. The cost of direct labor in countries like China is relatively lower in comparison to the cost of labor in the U.S. Edward Hill, professor at Cleveland State University's College of Urban Affairs, states that an hour of a manufacturing plant in the U.S. costs $150 versus $1 in China (Scherer, 2005). Companies are making strategic decisions based on reducing cost in order to improve profits. …

Growth Behavior Of Fibroblasts Influenced By Small Changes In Polymer Structure, Saraswathi Doddi

Theses

Polymers are a promising class of biomaterials that can be engineered to meet specific end use requirements. The order and processing history of the polymer, which would alter the molecular orientation of the material could have a significant contribution towards cellular attachment and in turn, cell growth on the particular polymer. Surface properties of the material were considered to directly influence the properties of the adherent cells including cellular growth and reorganization. The present study is aimed at comparing cell growth on polyarylates with that of polylactic acid in their original state or by introducing small changes in the surface …

Multifractal Analysis Of Heart Rate Variability Using Wavelet-Transform Modulus-Maxima Method, Chirag Jani

Theses

Physiological signals are complex and carry information of human health. Recent studies reveal that under normal conditions, the heart rate time series shows multifractal behavior. In contrast, HRV in the pathological state such as congestive heart failure exhibits more monofractal-like structure. Recent advances in the assessment of heart rate variability (HRV) uses a nonlinear dynamics approach. In this study, the main objective is to use the wavelet-transform modulus-maxima method for the multifractal analysis of the heart rate time senes.

The degree of the multifractality is defined by the singularities (a point in time series where a mathematical function is not …

In Vitro Evaluation Of Human Mesenchymal Stem Cell Neural Differentiation On Tyrsine-Derived Polyarylates And Polycarbonates, Yee-Shuan Lee

Theses

Present spinal cord injury treatments cannot restore motor and sensory functions caused by the injury. These functions can return in the hopes of repairing the neural cells with a tissue engineered designed scaffold complex. The scaffold complex will include cells to repair and replace the damaged cells.

Mesenchymal stem cells (MSC) are multipotent adult stem ells that are capable of differentiating along several lineage pathways. Neural stem cell and MSC differentiating along the neural lineage bave been investigated both in vivo and in vitro depicting its feasibility. MSC for neural differentiation can be achieved by microenvironmental signaling. Substrate surface characteristics …

Combined Effects Of Prozac And Hypothalmic Mediated Response On Masseter Muscle Activity In The Cat, Chika P. Nwaorgu

Theses

The present study tested the hypothesis that infusion of Prozac would serve to suppress defensive rage elicited from the medial hypothalamus of the cat. Cats are known to exhibit certain kind of behavior, known as the "defensive rage response" such as unsheathing of the claws, retraction of the ear and vocalization (hissing).

Three adult cats (2 males and 1 female) weighing (2.8 - 3.4 kg) were utilized during the experiments. Cannula-electrodes were implanted into the medial hypothalamus for elicitation of defensive rage behavior. EMG activity was recorded with a bipolar electrode attached to the masseter muscle to establish baseline before …

Generation Of Biomarkers From Anthrax Spores By Catalysis And Analytical Pyrolysis, Phillip R. Smith

Theses and Dissertations

Anthrax spores, in weaponized form, are dangerous biological warfare agents. Handheld technology for the rapid detection of anthrax is greatly needed to improve national security. Methods to detect anthrax spores are diverse, with most taking at least an hour for positive identification. A viable option for rapid detection is analytical pyrolysis (AP), which produces chemicals containing taxonomical information (biomarkers). AP methods are reviewed and critically analyzed to show that reproducible detection of anthrax spores in a rapid manner (< 5 min) with a handheld device is not currently possible. A promising alternative to AP is the use of a catalyst to produce biomarkers from anthrax spores with improved selectivity and reproducibility. Catalytic materials having promise for this include platinum, nickel, and superacids. Experiments evaluating several of these materials are described. A biomarker mass spectral library was created, based on information available in the scientific literature, to facilitate analysis and identification of the biomarkers produced experimentally. The RAMFAC algorithm was used to deconvolute chromatographic peaks to produce clean mass spectra and match them against entries in the biomarker library. While the library is not complete, its use with the RAMFAC algorithm enabled detection of many important biomarkers in experiments involving catalytic breakdown of anthrax spores. Experimental results from preliminary tests of several catalysts are presented and discussed. Addition of catalysts in the form of platinum nanoclusters and superacids to bacterial spores in a commercial pyrolyzer effected an increase in the amount of biomarkers produced at mild conditions over traditional pyrolysis methods. Electroformed nickel mesh, on the other hand, demonstrated low catalytic activity for the production of biomarkers, likely due to poor contact of the spores with the mesh. Biomarkers similar to those published in the literature were observed, including dipicolinic acid, picolinic acid, propionamide, acetamide, diketopiperazines, fatty acids, furfuryl alcohol, and DNA bases. A statistically designed factorial study was used to determine the importance of temperature, spore loading, and nanocluster loading on the production of three important biomarkers. The relative importance of these variables differs for each of the three important biomarkers, suggesting they are produced by different reaction mechanisms.

Stormwater Intelligent Control System (2005), Martin Wanielista

BMP Trains Research and Publications

Water restrictions, pollution control, volume balances, and the emergence of stormwater utilities have lead to the development of an automated intelligent system (“I-Water”) for water use and control. With the use of this system, water stored in stormwater ponds or in the surficial aquifer is not discharged to surface waters because it is used to meet water demands, such as, lawn irrigation, environmental protection, agriculture, drinking and industrial uses.

The drop in groundwater levels and the increasing use of reclaimed water illustrates a need for alternative water supplies. Ground water depletion is occurring which is adding to the destruction of …

Biodiesel Plant Investment—Making The Correct Decisions, Leland Tong, Steve Howell

Industrial Agricultural Products Center: Publications and Information

Overall Purpose of IBFG:
• Provide the most accurate, up-to-date, detailed, independent information on biodiesel and the biodiesel industry
• Provide Information you need to make an intelligent decision on a biodiesel plant….

Crosslinked Chitosan: Its Physical Properties And The Effects Of Matrix Stiffness On Chondrocyte Cell Morphology And Proliferation, Anuradha Subramanian, Hsin-Yi Lin

Papers in Biotechnology

Chitosan [<(1-4)-2 amino-2-deoxy-d-glucose], the natural polyaminosaccharide derived from N-deacetylation of chitin [<(1-4)-2 acetamide-2-deoxy-d-glucose], has been shown to possess attractive biological and cell interactive properties. Recently chitosan and chitosan analogs have also been shown to support the growth and continued function of chondrocytes. In the present study, chitosan substrates are crosslinked with a func-tional diepoxide (1,4 butanediol diglycidyl ether) to alter its mechanical property, and the viability and proliferation of the canine articular chondrocytes seeded on the crosslinked surface are further assayed. Of interest is the impact of substrate stiffness on the growth and proliferation of articular canine chondrocytes. Cross linked scaffolds were also sub-jected to degradation by chitosanase to examine the impact of cross linking on enzyme- assisted degradation. The hydrophilicity and compression modulus of the crosslinked sur-faces were measured via contact-angle measurements and compression tests, respec-tively. Scanning electron microscopy (SEM) and fluorescent staining were used to ob-serve the proliferation and morphology of chondrocyte cells on noncrosslinked and crosslinked surfaces. The crosslinked chitosan was found to be nontoxic to chondrocytes and more hydrophilic. Its compression modulus and stiffness increased, which may im-prove the scaffold resistance to wear and in vivo shrinkage once implanted. The in-creased stiffness also seemed to serve as an additional mechanical stimulus to promote chondrocyte growth and proliferation. The cell morphology on crosslinked scaffolds seen by SEM and fluorescent stain was the typical chondrocytic rounded shape. The method proposed provides a nontoxic way to increase the mechanical strength of the chitosan scaffolds.

Purification And Scale-Up Of A Recombinant Heavy Chain Fragment C Of Botulinum Neurotoxin Serotype E In Pichia Pastoris Gs115, Michael P. Dux, Rick Barent, Jayanta Sinha, Mark Gouthro, Todd Swanson, Ardis Barthuli, Mehmet İnan, John T. Ross, Leonard A. Smith, Theresa J. Smith, Robert Webb, Bonnie Loveless, Ian Henderson, Michael M. Meagher

Papers in Biochemical Engineering

A recombinant C-terminus heavy chain fragment from Botulinum neurotoxin serotype E (BoNT/E) is proposed as a vaccine against the serotype E neurotoxin. This fragment, rBoNTE(Hc), was produced intracellular in Pichia pastoris GS115 by a three-step fermentation process, i.e., glycerol batch phase and a glycerol fed-batch phase to achieve high cell densities, followed by a methanol fed-batch induction phase. The rBoNTE(Hc) protein was purified from the soluble fraction of cell lysates using three ion-exchange chromatography steps (SP Sepharose Fast Flow, Q Sepharose Fast Flow, Sp Sepharose High Performance) and polished with a hydrophobic charge induction chromatography step (MEP HyperCel). Method development …

A Chain-Type Wireless Sensor Network For Monitoring Long Range Infrastructures, Chang Wen Chen, Yu Wang, Ivica Kostanic

Electrical Engineering and Computer Science Faculty Publications

We present in this paper an investigation on a special class of wireless sensor networks for monitoring critical infrastructures that may extend for hundreds of miles in distances. Such networks are fundamentally different from traditional sensor networks in that the sensor nodes in this class of networks are deployed along narrowly elongated geographical areas and form a chain-type topology. Based on careful analysis of existing sensor network architectures, we first demonstrate the needs to develop new architecture and networking protocols to match the unique topology of chain-type sensor networks. We then propose hierarchical network architecture that consists of clusters of …

Design Optimization And Synthesis Of Manipulators Based On Various Manipulation Indices, Sandipak Bagchi

Mechanical and Aerospace Engineering Theses - Archive

Design optimization of serial manipulators involves striking a balance between an appropriate joint angle and exact link lengths. The optimization technique used in this thesis uses a unique algorithm that optimizes the joint angle through an Inverse Kinematics program. The synthesis problem involves setting up an accurate design length so as to reach a set of given target points inside the workspace without any singularity. The optimization process based on task specification focuses on the maximization of manipulability index, the objective function subjected to link length and joint angle constraints. The results obtained were plotted and animated to visualize the …

Cost Effective Human Protein C Purification From Cohn Fraction Iv-1 Using Mini-Antibody., Doh Gyeuhn Ahn 1969-

Electronic Theses and Dissertations

Protein C (PC) is an important anticoagulant, antithrombotic, and antiinflammatory in blood plasma. PC deficiency can lead to severe venous thrombotic events, including lung embolism, stroke, and heart attack. In the body, PC is activated only when it is needed, and, therefore, PC does not cause bleeding problems that currently available anticoagulants may do. Purification of PC from plasma is currently done by immunoaffinity chromatography using monoclonal antibodies (Mabs), which is very expensive. Single chain variable regions (mini-Mab) with a PC binding capability, which can be produced in recombinant E. coli , were developed for PC purification. Compared to Mabs, …

Manure Use Planning: An Evaluation Of A Producer Training Program, Charles S. Wortmann, Richard K. Koelsch, Charles A. Shapiro, Richard L. Deloughery, David D. Tarkalson

Department of Agricultural and Biological Systems Engineering: Faculty Publications

A training program for producers in manure use planning was evaluated. The potential for runoff nutrient loss to surface water can reduced and the value of manure increased through better planning of manure use. Training was conducted throughout Nebraska in 2002 and 2003. Livestock producers who attended evaluated the event at the end of the last class. The need for and impact of the training was greater for continuing operational and maintenance skills of manure utilization that are regularly needed for strategic planning skills. We recommend that training focus primarily on operational and maintenance skills.

Microfocal X-Ray Computed Tomography Post-Processing Operations For Optimizing Reconstruction Volumes Of Stented Arteries During 3d Computational Fluid Dynamics Modeling, John F. Ladisa, Lars E. Olson, Kristina M. Ropella, Robert C. Molthen, Steven Thomas Haworth, Judy R. Kersten, David C. Warltier, Paul S. Pagel

Biomedical Engineering Faculty Research and Publications

Restenosis caused by neointimal hyperplasia (NH) remains an important clinical problem after stent implantation. Restenosis varies with stent geometry, and idealized computational fluid dynamics (CFD) models have indicated that geometric properties of the implanted stent may differentially influence NH. However, 3D studies capturing the in vivo flow domain within stented vessels have not been conducted at a resolution sufficient to detect subtle alterations in vascular geometry caused by the stent and the subsequent temporal development of NH. We present the details and limitations of a series of post-processing operations used in conjunction with microfocal X-ray CT imaging and reconstruction to …