Open Access. Powered by Scholars. Published by Universities.®

Biomedical Engineering and Bioengineering Commons

Open Access. Powered by Scholars. Published by Universities.®

10,194 Full-Text Articles 18,523 Authors 3,886,775 Downloads 182 Institutions

All Articles in Biomedical Engineering and Bioengineering

Faceted Search

10,194 full-text articles. Page 387 of 396.

Osteoclast-Mediated Cell Therapy As An Attempt To Treat Elastin-Specific Vascular Calcification, Chartrisa Simpson 2010 Clemson University

Osteoclast-Mediated Cell Therapy As An Attempt To Treat Elastin-Specific Vascular Calcification, Chartrisa Simpson

All Dissertations

Vascular calcification occurs during physiological aging and is clinically recognized as a major risk factor for myocardial infarction, systolic hypertension, heart failure and coronary insufficiency caused by loss of aortic recoil. Medial arterial calcification is an active remodeling process that involves the deposition of bone-specific matrix in close association with elastic fibers. Elastin, a major structural protein in the extracellular matrix of arterial walls, provides elastic recoil to the arteries. Increasing evidence suggests that vascular calcification share features with skeletal bone formation such as bone matrix deposition and bone resorption. Bone morphogenetic proteins and bone cells have been found in …


Anaerobic Fermentation Of Hemicellulose Present In Green Liquor And Hot Water Extracts To Carboxylic Acids, Rakhi Reddy Baddam 2010 The University of Maine

Anaerobic Fermentation Of Hemicellulose Present In Green Liquor And Hot Water Extracts To Carboxylic Acids, Rakhi Reddy Baddam

Electronic Theses and Dissertations

Wood is composed of cellulose, hemicellulose and lignin. In the paper industry the cellulose fraction is the major resource used in paper production, whereas the hemicellulose and the lignin are usually burned for heat recovery. Recently, wood-derived hemicellulose extracts have received much attention for the production of valuable bioproduct fuels and chemicals. Mixed-culture microbial ecosystems are capable of converting biomass materials, such as wood extracts, into mixtures of carboxylic acids (C1-C7), which can in turn be purified and sold as products, or converted into other organic chemicals through chemical means. The relative concentrations of the acids produced in the fermentations …


Using The Continuous Wavelet Transform To Characterize Differences Between Impact Signals From Non-Cleated And Cleated Turf Shoes, Wayne Robert Fischer 2010 Boise State University

Using The Continuous Wavelet Transform To Characterize Differences Between Impact Signals From Non-Cleated And Cleated Turf Shoes, Wayne Robert Fischer

Boise State University Theses and Dissertations

The continuous wavelet transform was used to characterize the time-frequency differences between impact forces from non-cleated and cleated turf shoes among male football athletes who perform cut and run activities. This research is significant because it elucidates how athletes experience different impact force and torque frequency content based on the type of shoe they are wearing. The complex Morlet mother wavelet was used to analyze all ground reaction force and vertical ground reaction moment signals to create time-frequency power spectrum plots. For each signal, a statistical confidence interval was calculated and displayed along with the cone of influence caused by …


Effects Of Static Stretching On Foot Velocity During The Instep Soccer Kick, Craig D. Workman 2010 Utah State University

Effects Of Static Stretching On Foot Velocity During The Instep Soccer Kick, Craig D. Workman

All Graduate Theses and Dissertations

The purpose of this study was to assess the acute effects of static stretching on foot velocity at impact with a soccer ball. Eighteen Division I female soccer athletes underwent two test conditions separated by 48 hr. Each condition was randomly assigned and began by placing four retro-reflective markers on bony landmarks of the ankle (total of eight markers, four on each ankle). One condition was the no-stretch condition, in which each participant performed a self-paced jog for 5 min as a warm-up, and then sat quietly for 6 min before performing three maximal instep kicks into a net. The …


A Synthetic Biological Engineering Approach To Secretion- Based Recovery Of Polyhydroxyalkanoates And Other Cellular Products, Elisabeth Linton 2010 Utah State University

A Synthetic Biological Engineering Approach To Secretion- Based Recovery Of Polyhydroxyalkanoates And Other Cellular Products, Elisabeth Linton

All Graduate Theses and Dissertations

The costs associated with cellular product recovery commonly account for as much as 80% of the total production expense. As a specific example, significant recovery costs limit commercial use of polyhydroxyalkanoates (PHA), which comprise a class of microbially-accumulated polyesters. PHAs are biodegradable compounds that are of interest as a sustainable alternative to petrochemically-derived plastics. Secretion-based recovery of PHAs was studied to decrease PHA production costs. Type I and II secretory pathways are commonly used for the translocation of recombinant proteins out of the cytoplasm of E. coli. Proteins were targeted for translocation using four signal peptides (HlyA, TorA, GeneIII, …


The Hypericum Perforatum Herb As An Antimycobacterial Agent And Its Implications As An Additional Tuberculosis Medication, Trent W. Mortensen 2010 Utah State University

The Hypericum Perforatum Herb As An Antimycobacterial Agent And Its Implications As An Additional Tuberculosis Medication, Trent W. Mortensen

All Graduate Theses and Dissertations

An immediate demand exists for new tuberculosis (TB) antibiotics due to the ever-increasing spread of drug-resistant strains. The drug-development process goes through four phases, the first (Phase 0) of which is to demonstrate and investigate drug effectiveness and toxicity. This research investigated the effectiveness of the Hypericum perforatum herb (commonly St. John's wort (SJW)) in its growth inhibition of mycobacteria and its viability effect on human lung cells.

Organic-solvent SJW extracts were effective at inhibiting every nonpathogenic genetically sequenced Mycobacterium isolate currently available (six isolates) in preliminary studies. Quantitative studies of five Mycobacterium isolates showed an order of concentration sensitivity …


Comparative Studies On Oxygen Mass Transfer For The Design And Development Of A Single-Use Fermentor, Kristan L. Sorenson 2010 Utah State University

Comparative Studies On Oxygen Mass Transfer For The Design And Development Of A Single-Use Fermentor, Kristan L. Sorenson

All Graduate Theses and Dissertations

Accurate experimental oxygen mass transfer coefficient, a measure of how quickly oxygen travels from a gas bubble to the bulk liquid, is important for comparing performance and for evaluating the oxygen transfer capability of a fermentor. Delays in probe response and changing gas volumes upon start-up of gassing affect the accuracy of oxygen transfer measurements. To mitigate these inaccuracies, a standard correction procedure for oxygen mass transfer data was established for highly oxygenated, well-mixed fermentation systems. Probe response time correction was generated by applying a second-order response model to dissolved oxygen probes and shown to be effective within 4%. By …


Characterization And Physicochemical Modifications Of Polymer Hollow Fiber Membranes For Biomedical And Bioprocessing Applications, Benjamin R. Madsen 2010 Utah State University

Characterization And Physicochemical Modifications Of Polymer Hollow Fiber Membranes For Biomedical And Bioprocessing Applications, Benjamin R. Madsen

All Graduate Theses and Dissertations

Hollow fiber membranes (HFMs) formed through phase inversion methods exhibit specific physicochemical characteristics and generally favorable surface and mechanical properties, supporting their use in diverse applications including ultrafiltration, dialysis, cell culture, bioreactors, and tissue engineering. Characterization of, and modifications to, such membranes are important steps in achieving desired characteristics for specific applications. HFMs subject to gas, irradiation, and chemical sterilization techniques were characterized based on several analytical techniques. It was revealed that these common sterilization techniques can cause inadvertent changes to HFM properties. While these changes may cause detrimental effects to HFMs used in filtration, the methods of sterilization are …


Effects Of Reamer-Femoral Component Offset On Cement Mantle Penetration In Hip Resurfacing Arthroplasty, Mark Lloyd Paulick 2010 California Polytechnic State University, San Luis Obispo

Effects Of Reamer-Femoral Component Offset On Cement Mantle Penetration In Hip Resurfacing Arthroplasty, Mark Lloyd Paulick

Master's Theses

Hip resurfacing arthroplasty has changed the treatment of end stage arthritis without severe deformity for young, active adults. Presently, there are varying clinical approaches to implant design selection and cementation techniques. The purpose of this project is to determine what amount of reamer-femoral component offset allows for the best cement penetration into the femoral head.

Rapid prototyped femoral component models were produced with reamer femoral component offsets of 0.0 mm, 0.5 mm, and 1.0 mm. After implantation onto models of reamed femoral heads made from high-density open-cell reticulated carbon foam, cement penetration was assessed from cross-sections of the foam-implant unit. …


Mineralization Potential Of Electrospun Pdo-Nha-Fibrinogen Scaffolds Intended For Cleft Palate Repair, Isaac Rodriguez 2010 Virginia Commonwealth University

Mineralization Potential Of Electrospun Pdo-Nha-Fibrinogen Scaffolds Intended For Cleft Palate Repair, Isaac Rodriguez

Theses and Dissertations

The overall goal of this study was to identify mineralized scaffolds which can serve as potential alternatives to bone graft substitutes intended for cleft palate repair. The aim of this preliminary study was to evaluate the role of fibrinogen (Fg) and nano-hydroxyapatite (nHA) in enhancing mineralization potential of polydioxanone (PDO) electrospun scaffolds. Scaffolds were fabricated by blending PDO:nHA:Fg in the following weight ratios: 100:0:0, 50:25:25, 50:50:0, 50:0:50, 0:0:100 and 0:50:50. Scaffolds were immersed in different simulated body fluids for 5 and 14 days to induce mineralization. The inclusion of fibrinogen induced sheet-like mineralization while individual fiber mineralization was noticed in …


Electrophysiological Analysis In An Animal Model Of Dystonia, Kunal Chaniary 2010 Virginia Commonwealth University

Electrophysiological Analysis In An Animal Model Of Dystonia, Kunal Chaniary

Theses and Dissertations

Dystonia is a movement disorder characterized by patterned, repetitive, and sustained muscle contractions that cause ineffective and often painful movements. The overall goal of this project was to understand the physiological mechanisms of dystonia in a rodent model as a basis for developing innovative treatments for secondary dystonias. The first half of the project was focused at developing essential techniques for systematically investigating the movement disorder in these animals. For achieving this, an innovative, multi-faceted approach was pursued starting with electromyographic (EMG) analysis for animal model validation, gait analysis for dystonia quantification, and development of a novel stereotaxic apparatus for …


Determination Of Material Emission Signatures By Ptr-Ms And Their Correlations With Odor Assessments By Human Subjects, Kwanghoon Han 2010 BEESL Lab., Syracuse University

Determination Of Material Emission Signatures By Ptr-Ms And Their Correlations With Odor Assessments By Human Subjects, Kwanghoon Han

Kwanghoon Han

The objectives of this study were to determine volatile organic compound (VOC) emission signatures of nine typical building materials by using proton transfer reaction-mass spectrometry (PTR-MS) and to explore the correlation between the PTR-MS measurements and the measurements of acceptability by human subjects. VOC emissions from each material were measured in a 50-l small-scale chamber. Chamber air was sampled by PTR-MS to determine emission signatures. Sorbent tube sampling and TD-GC/MS analysis were also performed to identify the major VOCs emitted and to compare the resulting data with the PTR-MS emission signatures. The data on the acceptability of air quality assessed …


Synthesis Of An Endothelial Cell Mimicking Surface Containing Thrombomodulin And Endothelial Protein C Receptor, Karl E. Kador 2010 University of Nebraska at Lincoln

Synthesis Of An Endothelial Cell Mimicking Surface Containing Thrombomodulin And Endothelial Protein C Receptor, Karl E. Kador

Chemical & Biomolecular Engineering Theses, Dissertations, & Student Research

Synthetic materials for use in blood contacting applications have been studied for many years with limited success. One of the main areas of need for these materials is the design of synthetic vascular grafts for use in the hundreds of thousands of patients who have coronary artery bypass grafting, many without suitable veins for autologous grafts. The design of these grafts is constrained by two common modes of failure, the formation of intimal hyperplasia (IH) and thrombosis. IH formation has been previously linked to a mismatching of the mechanical properties of the graft and has been overcome by creating grafts …


Locked Plate Fixation Of Osteoporotic Humeral Shaft Fractures: Are Two Locking Screws Per Segment Enough?, David J. Hak, Peter Althausen, S J. Hazelwood 2010 University of Colorado at Denver and Health Sciences Center

Locked Plate Fixation Of Osteoporotic Humeral Shaft Fractures: Are Two Locking Screws Per Segment Enough?, David J. Hak, Peter Althausen, S J. Hazelwood

Biomedical Engineering

Objective: The purpose of this study was to compare the biomechanical behavior of using two versus three locking screws per bone segment in a cadaveric humerus fracture gap model.

Methods: Six matched pairs of elderly osteoporotic fresh–frozen human cadaveric humerii were used. An eight-hole locking compression plate was placed posteriorly on the humeral shaft and secured with either four or six bicortical locking screws. A 5-mm middiaphyseal gap osteotomy was created to simulate a comminuted fracture without bony contact. Specimens were tested in offset axial compression, four-point anteroposterior bending, four-point medial– lateral bending, and torsion. After the initial testing in …


Detecting Mutually-Salient Landmark Pairs With Mrf Regularization, Yangming Ou, Ahmed Besbes, Michel Bilello, Mohamed Mansour, Christos Davatzikos, Nikos Paragios 2010 University of Pennsylvania

Detecting Mutually-Salient Landmark Pairs With Mrf Regularization, Yangming Ou, Ahmed Besbes, Michel Bilello, Mohamed Mansour, Christos Davatzikos, Nikos Paragios

Departmental Papers (BE)

In this paper, we present a framework for extracting mutually-salient landmark pairs for registration. Traditional methods detect landmarks one-by-one and separately in two images. Therefore, the detected landmarks might inherit low discriminability and are not necessarily good for matching. In contrast, our method detects landmarks pair-by-pair across images, and those pairs are required to be mutually-salient, i.e., uniquely corresponding to each other. The second merit of our framework is that, instead of finding individually optimal correspondence, which is a local approach and could cause self-intersection of the resultant deformation, our framework adopts a Markov-random-field (MRF)-based spatial arrangement to select the …


An Integrated, Self-Contained Microfluidic Cassette For Isolation, Amplification, And Detection Of Nucleic Acids, Dafeng Chen, Michale Mauk, Xianbo Qiu, Changchun Liu, Jitae Kim, Sudhir Ramprasad, Serge Ongagna, William Abrams, Daniel Malamud, Paul Corstjens, Haim H. Bau 2010 University of Pennsylvania

An Integrated, Self-Contained Microfluidic Cassette For Isolation, Amplification, And Detection Of Nucleic Acids, Dafeng Chen, Michale Mauk, Xianbo Qiu, Changchun Liu, Jitae Kim, Sudhir Ramprasad, Serge Ongagna, William Abrams, Daniel Malamud, Paul Corstjens, Haim H. Bau

Departmental Papers (MEAM)

A self-contained, integrated, disposable, sample-to-answer, polycarbonate microfluidic cassette for nucleic acid-based detection of pathogens at the point of care was designed, constructed, and tested. The cassette comprises on-chip sample lysis, nucleic acid isolation, enzymatic amplification (polymerase chain reaction and, when needed, reverse transcription), amplicon labeling, and detection. On-chip pouches and valves facilitate fluid flow control. All the liquids and dry reagents needed for the various reactions are pre-stored in the cassette. The liquid reagents are stored in flexible pouches formed on the chip surface. Dry (RT-)PCR reagents are pre-stored in the thermal cycling, reaction chamber. The process operations include sample …


Dna Microarray Image Segmentation Using Active Contours Without Edges Method, Shenghua Ni 2010 Louisiana Tech University

Dna Microarray Image Segmentation Using Active Contours Without Edges Method, Shenghua Ni

Doctoral Dissertations

The goal of this dissertation is to build a better segmentation method for DNA microarray image processing. Segmentation is a partitioning process used to separate a spot area from a non-spot area in DNA microarrays. It directly affects the accuracy of gene expression analysis in the data mining process that follows. A number of DNA microarray segmentation methods have been proposed in the area, but even modern segmentation methods seem to have accuracy problems. In this dissertation, I will present a segmentation method based on the Active Contours Without Edges (ACWE) algorithm and apply it to two types of DNA …


Characterization Of An Implicitly Resistively-Loaded Monopole Antenna In Lossy Liquid Media, Colleen J. Fox, Paul M. Meaney, Fridon Shubitidze, Lincoln Potwin, Keith D. Paulsen 2010 Dartmouth College

Characterization Of An Implicitly Resistively-Loaded Monopole Antenna In Lossy Liquid Media, Colleen J. Fox, Paul M. Meaney, Fridon Shubitidze, Lincoln Potwin, Keith D. Paulsen

Dartmouth Scholarship

Abstract

Microwave tomographic imaging of the breast for cancer detection is a topic of considerable interest because of the potential to exploit the apparent high-dielectric property contrast between normal and malignant tissue. An important component in the realization of an imaging system is the antenna array to be used for signal transmission/detection. The monopole antenna has proven to be useful in our implementation because it can be easily and accurately modeled and can be positioned in close proximity to the imaging target with high-element density when configured in an imaging array. Its frequency response is broadened considerably when radiating in …


Biomechanical Comparison Of Wire Circlage And Rigid Plate Fixation For Median Sternotomy Closure In Human Cadaver Specimens, Mark Steven Wong 2010 California Polytechnic State University, San Luis Obispo

Biomechanical Comparison Of Wire Circlage And Rigid Plate Fixation For Median Sternotomy Closure In Human Cadaver Specimens, Mark Steven Wong

Master's Theses

Background:

Over 700,000 patients per year undergo open-heart surgery. Healing complication rates can be up to 5% of patients who undergo this procedure, with a morbidity rate of 50% if mediastinitis supervenes. A secure and rigid fixation of surgically divided sternum is critical to avoid healing complications. The purpose of this study was to compare the yield load, construct stiffness, ultimate load, displacement at ultimate load, and post-yield behavior of three sternotomy closure methods (Peristernal wires or Sternalock titanium plates) when stressed in each of three directions: lateral distraction, rostro-caudal (longitudinal) shear distraction, and anterior-posterior (transverse) shear in a cadaveric …


Effect Of Loading Condition On Traction Coefficient Between Shoes And Artificial Turf Surfaces, Seth M. Kuhlman, Michelle B. Sabick, Ronald Pfeiffer, Benjamin Cooper, Jackie Forhan 2010 Boise State University

Effect Of Loading Condition On Traction Coefficient Between Shoes And Artificial Turf Surfaces, Seth M. Kuhlman, Michelle B. Sabick, Ronald Pfeiffer, Benjamin Cooper, Jackie Forhan

Mechanical and Biomedical Engineering Faculty Publications and Presentations

Background. The interaction between a shoe and a turf surface is highly complex and difficult to characterize. Over the three decades since artificial turf was introduced, researchers have attempted to understand the traction caused by the interaction. However, some of the methodologies used for traction measurements have not capitalized on advances in currently available technology for testing and most testing conditions have not simulated realistic physiological loads.

Method of Approach. To assess the effect of test condition on traction results, the newly designed TurfBuster testing device was used to collect traction data on FieldTurf™ brand artificial turf under varying conditions. …


Digital Commons powered by bepress