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Recombinant Factors For Hemostasis, Jennifer Calcaterra 2010 University of Nebraska at Lincoln

Recombinant Factors For Hemostasis, Jennifer Calcaterra

Chemical & Biomolecular Engineering Theses, Dissertations, & Student Research

Trauma deaths are a result of hemorrhage in 37% of civilians and 47% military personnel and are the primary cause of death for individuals under 44 years of age. Current techniques used to treat hemorrhage are inadequate for severe bleeding. Preliminary research indicates that fibrin sealants (FS) alone or in combination with a dressing may be more effective; however, it has not been economically feasible for widespread use because of prohibitive costs related to procuring the proteins. To meet future demands for hemostatic therapies, FS will likely include recombinant human fibrinogen (rFI) and recombinant human Factor XIII (rFXIII). The underlying ...


Biogeography-Based Optimization Of Neuro-Fuzzy System Parameters For Diagnosis Of Cardiac Disease, Mirela Ovreiu, Daniel J. Simon 2010 Cleveland Clinic Foundation

Biogeography-Based Optimization Of Neuro-Fuzzy System Parameters For Diagnosis Of Cardiac Disease, Mirela Ovreiu, Daniel J. Simon

Electrical Engineering & Computer Science Faculty Publications

Cardiomyopathy refers to diseases of the heart muscle that becomes enlarged, thick, or rigid. These changes affect the electrical stability of the myocardial cells, which in turn predisposes the heart to failure or arrhythmias. Cardiomyopathy in its two common forms, dilated and hypertrophic, implies enlargement of the atria; therefore, we investigate its diagnosis through P wave features. In particular, we design a neuro-fuzzy network trained with a new evolutionary algorithm called biogeography-based optimization (BBO). The neuro-fuzzy network recognizes and classifies P wave features for the diagnosis of cardiomyopathy. In addition, we incorporate opposition-based learning in the BBO algorithm for improved ...


Biogeography-Based Optimization With Blended Migration For Constrained Optimization Problems, Haiping Ma, Daniel J. Simon 2010 Shaoxing University, Shaoxing, China

Biogeography-Based Optimization With Blended Migration For Constrained Optimization Problems, Haiping Ma, Daniel J. Simon

Electrical Engineering & Computer Science Faculty Publications

Biogeography-based optimization (BBO) is a new evolutionary algorithm based on the science of biogeography. We propose two extensions to BBO. First, we propose blended migration. Second, we modify BBO to solve constrained optimization problems. The constrained BBO algorithm is compared with solutions based on a genetic algorithm (GA) and particle swarm optimization (PSO). Numerical results indicate that BBO generally performs better than GA and PSO in handling constrained single-objective optimization problems.


Proposed Implementation Of The Indiana Erosion And Sediment Control Field Guide, Lynn A. Corson 2010 Environmental Management Concepts, LLC

Proposed Implementation Of The Indiana Erosion And Sediment Control Field Guide, Lynn A. Corson

JTRP Technical Reports

No abstract provided.


Snow And Ice Removal And Anti-Icing Synthesis Study, Bob McCullouch 2010 Purdue University

Snow And Ice Removal And Anti-Icing Synthesis Study, Bob Mccullouch

JTRP Technical Reports

No abstract provided.


Fatigue Strength Of Steel Bridge Members With Intersecting Welds, David T. DeLong, Mark D. Bowman 2010 Purdue University

Fatigue Strength Of Steel Bridge Members With Intersecting Welds, David T. Delong, Mark D. Bowman

JTRP Technical Reports

The brittle fracture of the Hoan Bridge in December 2000 highlighted the fracture susceptibility of details containing intersecting welds in steel bridges. Though it is now known that details with intersecting welds should be avoided, many existing bridges in Indiana contain details with intersecting welds. Little experimental data on the fatigue performance of these details exists.

The purpose of this study was to evaluate the fatigue strength of several details commonly found in steel bridges in Indiana that contain intersecting welds. Large-scale experimental fatigue testing were performed using nine steel beams to study the behavior of three basic types of ...


Improved Modeling And Optimal Control Of An Electric Arc Furnace, Jared James Snell 2010 University of Iowa

Improved Modeling And Optimal Control Of An Electric Arc Furnace, Jared James Snell

Theses and Dissertations

This thesis centers around an electric arc furnace (EAF) at a steel mini-mill in Wilton, IA. First, the thesis replicates previous optimization attempts. Next, the modeling is greatly altered to produce a much improved steel-melting model. Then, a new optimal control system is created and used to reduce energy and fuel costs over the melting process. Finally, results are presented. This thesis shows that when the new optimal control is simulated, the system shows significant energy and fuel savings.


Regional Lung Function And Mechanics Using Image Registration, Kai Ding 2010 University of Iowa

Regional Lung Function And Mechanics Using Image Registration, Kai Ding

Theses and Dissertations

The main function of the respiratory system is gas exchange. Since many disease or injury conditions can cause biomechanical or material property changes that can alter lung function, there is a great interest in measuring regional lung function and mechanics.

In this thesis, we present a technique that uses multiple respiratory-gated CT images of the lung acquired at different levels of inflation with both breath-hold static scans and retrospectively reconstructed 4D dynamic scans, along with non-rigid 3D image registration, to make local estimates of lung tissue function and mechanics. We validate our technique using anatomical landmarks and functional Xe-CT estimated ...


Evaluation Of Biogas Generation From Turkey Waste, Anup Pudasaini 2010 University of Iowa

Evaluation Of Biogas Generation From Turkey Waste, Anup Pudasaini

Theses and Dissertations

This project investigates local industrial biomass streams as feedstocks for the generation of low-cost sustainable energy for The University of Iowa. Methane gas produced during anaerobic digestion would fuel an engine to generate electricity at the University of Iowa Research Park (Oakdale Campus). A current local industry identified for this project is West Liberty Foods (WLF), a turkey processing facility located in West Liberty, Iowa, USA. WLF generates about 6,000 gal/day of blood, 40,000 lb/day of offal (guts), 6,000 lb/day of sludge (process waste water) and 2-4 truckloads/day of feathers as waste streams ...


Sediment-Size Analysis, Nitrate Monitoring, Bathymetric Mapping And Construction Of A Two-Dimensional Hydrodynamic Model Of A Backwater Region Of The Upper Mississippi River System 2008-2009, Nathan Anderson Quarderer 2010 University of Iowa

Sediment-Size Analysis, Nitrate Monitoring, Bathymetric Mapping And Construction Of A Two-Dimensional Hydrodynamic Model Of A Backwater Region Of The Upper Mississippi River System 2008-2009, Nathan Anderson Quarderer

Theses and Dissertations

In April 2008, the non-profit organization Living Lands & Waters (LL&W) approached IIHR-Hydroscience and Engineering to assist with the preliminary scoping and assessment for the proposed dredging and restoration of the backwater region located near the confluence of the Iowa and Mississippi Rivers, commonly referred to as Boston Bay. IIHR was responsible for the measurement and analysis of relevant physical and chemical parameters including particle-size analysis of sediment cores; real-time monitoring of nitrate-nitrogen concentration of agricultural runoff entering Boston Bay; bathymetric surveying; as well as the development of a two-dimensional hydrodynamic capable of simulating the proposed dredging activity.

Particle-size analysis was achieved using the hydrometer method of sedimentation to determine the distribution of fine particles (silt and clay) while traditional sieving techniques were employed to establish the proportions of sand-sized particles. Results indicate that the sediment contained in Boston Bay consists primarily of particles with diameters in the range of 2-50 µm, what the USDA considers silt, and clay.

A real-time ...


Examining Driver Performance In Response To Work Zone Interventions In A Driving Simulator, Michelle Lynn Reyes 2010 University of Iowa

Examining Driver Performance In Response To Work Zone Interventions In A Driving Simulator, Michelle Lynn Reyes

Theses and Dissertations

Reductions in speed and, more critically, speed variability between vehicles are thought to reduce crash risk in work zones. Numerous factors, such as lane width and lateral clearance and activity level, have been shown to influence speed but very little research has considered how multiple factors might interact to affect driver performance in work zones. This study evaluated the effect of work zone barrier type, presence of a lateral buffer, and work zone activity level on measures of speed and lane position. Twelve middle aged and twelve senior subjects drove in a National Advanced Driving Simulator (NADS) MiniSim. The subjects ...


Advancements Of A Servohydraulic Human Hip Joint Motion Simulator For Experimental Investigation Of Hip Joint Impingement/Dislocation, Nicholas James Stroud 2010 University of Iowa

Advancements Of A Servohydraulic Human Hip Joint Motion Simulator For Experimental Investigation Of Hip Joint Impingement/Dislocation, Nicholas James Stroud

Theses and Dissertations

A servohydraulic hip simulator was upgraded to experimentally investigate cadaveric impingement/dislocation of the hip with clinically releveant joint motions. The resulting biomechanical analysis provided insight into risk factors for dislocation/impingement and clearly demonstrated the potential of the hip simulator as a research tool.


Enzymatic And Chemical Modification Of Fatty Acid Methyl Esters: Enzymatic Catalysis Of Methyl Linoleate Using Soybean Lipoxygenase And Chemical Catalysis Of Methyl Oleate Using Hypobromination, Matthew John Scholten 2010 University of Iowa

Enzymatic And Chemical Modification Of Fatty Acid Methyl Esters: Enzymatic Catalysis Of Methyl Linoleate Using Soybean Lipoxygenase And Chemical Catalysis Of Methyl Oleate Using Hypobromination, Matthew John Scholten

Theses and Dissertations

Vegetable oils are a cheap and abundant chemical feedstock which can be readily broken down into fatty acid methyl esters (FAMEs) by transesterification using methanol and a base catalyst. These FAMEs contain reactive unsaturated double bonds which can be targeted for modification. In this study, enzymatic and chemical modifications of the unsaturated double bonds of FAMEs are explored with the goal of producing higher value products. Specifically the enzymatic modification of methyl linoleate using soybean lipoxygenase and the chemical modification of methyl oleate using hypobromantion are studied.


A Biomechanical Model Of Femoral Forces During Functional Electrical Stimulation After Spinal Cord Injury In Supine And Seated Positions, Colleen Louise McHenry 2010 University of Iowa

A Biomechanical Model Of Femoral Forces During Functional Electrical Stimulation After Spinal Cord Injury In Supine And Seated Positions, Colleen Louise Mchenry

Theses and Dissertations

Following a spinal cord injury (SCI), the paralyzed extremities undergo muscle atrophy and decrease in bone mineral density (BMD) due in part to the loss of physiological loading. It is crucial to prevent musculoskeletal deterioration so the population is less susceptible to fractures, and could take advantage of stem cell treatment if it becomes available. Functional electrical stimulation (FES) has been shown to advantageously train the paralyzed extremities. However, there is a risk of fracture during FES due to low BMD of individuals with SCI. Therefore, the forces generated during FES need to be modeled so researchers and clinicians safely ...


Sparse X-Ray Ct Image Reconstruction Using Ecme Hard Thresholding Methods, Kun Qiu, Aleksandar Dogandžić 2010 Iowa State University

Sparse X-Ray Ct Image Reconstruction Using Ecme Hard Thresholding Methods, Kun Qiu, Aleksandar Dogandžić

Center for Nondestructive Evaluation Conference Papers, Posters and Presentations

We apply expectation‐conditional maximization either (ECME) hard thresholding algorithms to X‐ray computed tomography (CT) reconstruction, where we implement the sampling operator using the nonuniform fast Fourier transform (NUFFT). The measurements follow an underdetermined linear model, where the regression‐coefficient vector is a sum of an unknown deterministic sparse signal component and a zero‐mean white Gaussian component with an unknown variance. Our ECME schemes aim at maximizing this model’s likelihood function with respect to the sparse signal and variance of the random signal component. These schemes exploit signal sparsity in the discrete wavelet transform (DWT) domain and ...


Development Of A Portable Mechanical Hysteresis Measurement And Imaging System For Impact Characterization In Honeycomb Sandwich Structures, Daniel J. Barnard, David K. Hsu 2010 Iowa State University

Development Of A Portable Mechanical Hysteresis Measurement And Imaging System For Impact Characterization In Honeycomb Sandwich Structures, Daniel J. Barnard, David K. Hsu

Center for Nondestructive Evaluation Conference Papers, Posters and Presentations

Honeycomb sandwich materials are commonly used for aero‐structures, but because the outer skins are typically thin, 2–10 plys, the structures are susceptible to impact damage. NDI methods such as tap tests, bond testers and TTU ultrasound are successfully deployed to find impact damage, but identifying the type∕degree of damage is troublesome. As the type∕degree of impact damage guides decisions by the maintenance, repair and overhaul (MRO) community regarding repair, the ability to characterize impacts is of interest. Previous work demonstrated that additional impact characterization may be gleaned from hysteresis loop area, as determined from an out ...


Characterization Of Residual Stresses In Ferrous Components By Magnetic Anisotropy Measurements Using A Hall Effect Sensor Array Probe, Chester C.H. Lo 2010 Iowa State University

Characterization Of Residual Stresses In Ferrous Components By Magnetic Anisotropy Measurements Using A Hall Effect Sensor Array Probe, Chester C.H. Lo

Center for Nondestructive Evaluation Conference Papers, Posters and Presentations

A new surface sensor probe comprising an angular array of Hall effect sensors has been developed for characterization of residual stresses in ferrous materials by means of stress‐induced magnetic anisotropy measurements. The sensor probe applies a radially spreading ac magnetic field to a test sample, and detects stray fields in different directions simultaneously to determine the principal stress axes. In situ measurements were conducted on a annealed steel plate under four‐point bending stresses to evaluate the probe performance. The ratio of stray field signals measured along and perpendicular to the stress axis varies linearly with the surface stress ...


Simple Go/No-Go Test For Subcritical Damage In Body Armor Panels, Jason T. Fisher, Dale E. Chimenti 2010 Iowa State University

Simple Go/No-Go Test For Subcritical Damage In Body Armor Panels, Jason T. Fisher, Dale E. Chimenti

Center for Nondestructive Evaluation Conference Papers, Posters and Presentations

The development of a simple test for subcritical damage in body armor panels using pressure‐sensitive dye‐indicator film has been performed and demonstrated effective. Measurements have shown that static indicator levels are accurately reproduced in dynamic loading events. Impacts from hard blunt impactors instrumented with an accelerometer and embedded force transducer were studied. Reliable correlations between the indicator film and instrumented impact force are shown for a range of impact energies. Force and acceleration waveforms with corresponding indicator film results are presented for impact events onto damaged and undamaged panels. We find that panel damage can occur at impact ...


Characterization Of Waviness In Wind Turbine Blades Using Air Coupled Ultrasonics, Sunil Kishore Chakrapani, Vinay Dayal, David K. Hsu, Daniel J. Barnard, Andrew Gross 2010 Iowa State University

Characterization Of Waviness In Wind Turbine Blades Using Air Coupled Ultrasonics, Sunil Kishore Chakrapani, Vinay Dayal, David K. Hsu, Daniel J. Barnard, Andrew Gross

Center for Nondestructive Evaluation Conference Papers, Posters and Presentations

Waviness in glass fiber reinforced composite is of great interest in composite research, since it results in the loss of stiffness. Several NDE techniques have been used previously to detect waviness. This work is concerned with waves normal to the plies in a composite. Air‐coupled ultrasonics was used to detect waviness in thick composites used in the manufacturing of wind turbine blades. Composite samples with different wave aspect ratios were studied. Different wavy samples were characterized, and a three step process was developed to make sure the technique is field implementable. This gives us a better understanding of the ...


Flaw Detection In A Multi-Material Multi-Layered Composite: Using Fem And Air-Coupled Ut, Richard A. Livings, Vinay Dayal, Daniel J. Barnard, David K. Hsu 2010 Iowa State University

Flaw Detection In A Multi-Material Multi-Layered Composite: Using Fem And Air-Coupled Ut, Richard A. Livings, Vinay Dayal, Daniel J. Barnard, David K. Hsu

Center for Nondestructive Evaluation Conference Papers, Posters and Presentations

Ceramic tiles are the main ingredient of a multi‐layer multi‐material composite being considered for the modernization of tank armors. The high stiffness, low attenuation, and precise dimensions of these uniform tiles make them remarkable resonators when driven to vibrate. This study is aimed at modeling the vibration modes of the tiles and the composite lay‐up with finite element analysis and comparing the results with the resonance modes observed in air‐coupled ultrasonic excitation of the tiles and armor samples. Defects in the tile, during manufacturing and∕or after usage, are expected to change the resonance modes. The ...


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