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

Digital Commons Network™

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

2009

Discipline
Institution
Keyword
Publication
Publication Type
File Type

Articles 991 - 1020 of 16971

Full-Text Articles in Entire DC Network

Mechanical And Chemical Characterization Of Biological Composite Structures, Bonnie Zimmerman Dec 2009

Mechanical And Chemical Characterization Of Biological Composite Structures, Bonnie Zimmerman

All Theses

A better understanding of the bioresponse of naturally occurring systems will help
to optimize the engineering of synthetic biomaterials. The aim of this thesis was to
characterize the mechanical and chemical behavior of two distinct biological composite
systems, human teeth and wool fibers. These mechanical and chemical properties were
also studied as a function of natural structure and environmental conditions.
Human teeth are composite systems consisting primarily of hydroxylapatite and
protein. This project investigated how the use of clinical dental treatments and
procedures, such as whitening and etching, affects mechanical properties. Analysis of
nanoindentation with the Oliver-Pharr model provided elastic …

Go to article

Hydrogel Compositions For Nonviral Gene Delivery, Eunhee Cho Dec 2009

Hydrogel Compositions For Nonviral Gene Delivery, Eunhee Cho

All Dissertations

The incorporation of nonviral vectors into biomaterial matrices has been employed to improve localization at the implant site and to protect from loss by clearance or extracellular barriers. However, several limitations such as detrimental crosslinking mechanisms, uncontrolled burst release require improved design of matrix-based gene delivery systems that provides sustained and controlled vector release as well as overcomes extracellular barriers to gene transfer in proximity to target cells. The long-term objective of this dissertation project is to provide the basis for the eventual creation of tissue engineering scaffolds that combine structural and biological activity through the creation of composite materials …

Go to article

Exploring T. Brucei Hexokinase Biology: Localization And Inhibition Studies, Todd Lyda Dec 2009

Exploring T. Brucei Hexokinase Biology: Localization And Inhibition Studies, Todd Lyda

All Dissertations

Trypanosoma brucei, the causative agent of the disease African sleeping sickness
in humans and nagana in animals, is a scourge of sub-Saharan Africa. There is a
desperate need for more efficacious therapies for the disease; here we describe research
validating T. brucei hexokinase 1 (TbHK1) as a drug therapeutic target for T. brucei
infection and the identification and characterization of novel inhibitors of the enzyme by
both low throughput and high throughput means. Additionally this thesis introduces
efforts at characterizing a second T. brucei hexokinase, focusing mostly on cell biology
and the determination of localization.
The small molecule quercetin (QCN) …

Go to article

An Approach Designed For Reginal Prospective Human Health And Ecological Risk Assessment And Its Application To Mercury Risks From A Coal-Fired Power Plant, Pathratipa Sansayavichai Dec 2009

An Approach Designed For Reginal Prospective Human Health And Ecological Risk Assessment And Its Application To Mercury Risks From A Coal-Fired Power Plant, Pathratipa Sansayavichai

All Dissertations

A large and/or long-term released source of a toxic chemical(s) can cause adverse effects to humans and non–human species inhabiting all over the region. The overall goal of this dissertation was to improve practices in risk assessment concerning a regional risk posed by a prospective source. A generic conceptual framework for performing regional prospective human health and ecological risk assessment was developed. The formulation of a priori considerations was used to identify the possible sources of uncertainties in the prospective risk assessment. Physiologically based pharmacokinetic (PBPK) modeling was utilized to reduce uncertainty in a toxicologically safe dose used in risk …

Go to article

Development Of A Fluorescent Probe For Determination Of Water Transport In Subcellular Organelles, Adriana Chaurra-Arboleda Dec 2009

Development Of A Fluorescent Probe For Determination Of Water Transport In Subcellular Organelles, Adriana Chaurra-Arboleda

All Dissertations

Water transport has been widely studied in a variety of cells and isolated membranes. However, the intrinsic complexity related with the study of intracellular processes has delayed the development of an analytical technique for the study of water transport in subcellular compartments of living cells. This study represents the development and application of a ratiometric fluorescent probe to study water transport in endocytic organelles of intact living cells. The probe is based on the use of a D2O-sensitive fluorophore, Lucifer yellow dextran (LY-dex), together with a D2O-insensitive fluorophore, Alexa fluor 546 dextran (AF546-dex), used as an …

Go to article

Synthesis And Characterization Of Metallic, Core-Shell And Composite Nanoparticles, Amar Kumbhar Dec 2009

Synthesis And Characterization Of Metallic, Core-Shell And Composite Nanoparticles, Amar Kumbhar

All Dissertations

ABSTRACT
Silver nanoparticles exhibit size, shape and the surrounding dielectric medium dependent optical properties (scattering and absorption) in the visible spectral region. These optical properties can be explained in terms of the collective oscillation of the 'free conduction band electrons' or 'surface plasmons' induced by an external electromagnetic field. Dipole and Quadrupole Plasmon resonances have been observed for silver particles less than 100nm in diameter prepared using various synthetic techniques. However higher order resonances have been elusive due to lack of experimental techniques to prepare colloidal solutions of large silver nanoparticles in the size range above 100nm. Controlled hydrogen reduction …

Go to article

Prosthetic Configurations: Rethinking Relationships Of Bodies, Technologies, And (Dis)Abilities, Amanda Booher Dec 2009

Prosthetic Configurations: Rethinking Relationships Of Bodies, Technologies, And (Dis)Abilities, Amanda Booher

All Dissertations

This work rethinks configurations of and relationships between bodies and prosthetics, emerging from a gap between three particular theoretical perspectives. The first perspective builds from Gender and Disability Studies theories; the second operates within the frame of post–humanity and cyborgean theories, specifically though Bernard Stiegler, Katherine Hayles, and Donna Haraway; the third is a practical/medical perspective, demonstrated through the experiences of people with amputations and medical prosthetics, as well as through the influence of medical visualization technologies. While offering productive and compelling means of complicating and deconstructing boundaries of bodies and prosthetics, these perspectives often operate independently; an integrative perspective …

Go to article

Functional Characterization Of Calcium Dependent Protein Kinase 32 From Arabidopsis, Rucha Karve Dec 2009

Functional Characterization Of Calcium Dependent Protein Kinase 32 From Arabidopsis, Rucha Karve

All Dissertations

Calcium-dependent protein kinases (CPKs) are major plant Ca2+ sensors, many of which have roles in plant stress responses. The Arabidopsis genome encodes 34 CPK isoforms. Here we report characterization of AtCPK32 gene function. Analysis of transgenic plants expressing pCPK32-GUS shows that CPK32 is highly expressed in roots, pollen and embryo, as well as leaf hydathodes, and the abscission zone of mature siliques. Real time RT-PCR and promoter expression patterns show that CPK32 is responsive to abiotic and biotic stresses. Plants treated with salt, ABA, osmotic stress (PEG), wounding, and flagellin 22 peptide show up-regulation of CPK32 upon these stress treatments. …

Go to article

Characterization Of Gulf Sturgeon Diel And Seasonal Activity In The Pensacola Bay System, Florida, Beth Wrege Dec 2009

Characterization Of Gulf Sturgeon Diel And Seasonal Activity In The Pensacola Bay System, Florida, Beth Wrege

All Dissertations

We assess temporal and spatial distribution and diel variability in activity of Gulf of Mexico sturgeon Acipenser oxyrinchus desotoi in the Pensacola Bay system, Florida, using stationary ultrasonic telemetry. Gulf of Mexico sturgeon (n = 54) migrated through the bay system in fall to wintering areas in the Gulf of Mexico and Santa Rosa Sound. In spring, sturgeon migrated back through the bay system to summering habitats in rivers. Gulf of Mexico sturgeon use East Bay and Escambia Bay primarily as migration routes between riverine areas used in spring and summer and the Gulf of Mexico used in winter. North …

Go to article

The Development Of A Mesenchymal Stem Cell Based Bone Graft System, Sarina Sinclair Dec 2009

The Development Of A Mesenchymal Stem Cell Based Bone Graft System, Sarina Sinclair

All Dissertations

Greater than 5.5 million fractures are sustained by Americans each year, accounting for more than 500,000 bone graft surgeries. Bone grafts are the second most transplanted material, surpassed only by blood. The current 'gold standard' for bone grafting involves harvesting bone material from the patient's iliac crest, due to its osteoinductive properties. Unfortunately, the surgery required to harvest material from the iliac crest causes additional pain for the patient, relies on a limited amount of available bone tissue, and results in, on average, a 30% rate of donor site morbidity. Both natural and synthetic substitutes have been developed to avoid …

Go to article

An Investigation On The Use And Flexibility Of Genetic Algorithms For Logistic Regression, Sara Yoder Dec 2009

An Investigation On The Use And Flexibility Of Genetic Algorithms For Logistic Regression, Sara Yoder

All Dissertations

Social scientists and other users of large data sets often desire a model to predict the probability that some condition exists, such as the probability that a person has diabetes or that a credit card transaction will be fraudulent. In general, this can be done by data mining techniques, which allow multiple records of data composed of numerous independent variables and one dependent variable to be examined in a statistical fashion to make a predictive model. One particular technique used is logistic regression. Logistic regression forms a predictive model based on a set of independent variables by assigning coefficients to …

Go to article

Probabilistic Remediation Evaluation Model For Chlorinated Solvents Considering Uncertainty, Hailian Liang Dec 2009

Probabilistic Remediation Evaluation Model For Chlorinated Solvents Considering Uncertainty, Hailian Liang

All Dissertations

The complex processes and expensive costs of source and plume remediation of dense, non-aqueous phase liquid (DNAPL) complicate the decision-making process for site remediation. Selection of remediation alternatives has been a big challenge due to the lack of tools that simultaneously evaluate the effectiveness of source and plume remediation and access the uncertainties in all major parameters. In this research, a new probabilistic remediation model, Probabilistic Remediation Evaluation Model for Chlorinated solvents sites (PREMChlor), has been developed. This is achieved through linking the analytical model REMChlor to a Monte Carlo modeling simulation package GoldSim via a FORTRAN Dynamic Link Library …

Go to article

Nucleation And Growth Behavior Of Tellurite-Based Glasses Suitable For Mid-Infrared Applications, Jonathan Massera Dec 2009

Nucleation And Growth Behavior Of Tellurite-Based Glasses Suitable For Mid-Infrared Applications, Jonathan Massera

All Dissertations

Optical fibers transmitting in the 2-5 μm mid-infrared (MIR) spectral region are highly desirable for a variety of military and civilian applications including super-continuum generation, infrared countermeasures (IRCM), and MIR laser sources. These new applications in the mid-infrared require novel optical materials that transmit in this window and can be fabricated into fiber. As tellurite glasses are known to have good transparency in the (NIR) region, tellurite-based glasses are the material of choice for this study due to their high linear and nonlinear refractive index, their low glass transition temperature and the ability to form them into optical fiber.
This …

Go to article

A Scanpath Comparison Of The Salient Features Of Weather Among General Aviation Pilots Based On Training And Experience, Michael Sawyer Dec 2009

A Scanpath Comparison Of The Salient Features Of Weather Among General Aviation Pilots Based On Training And Experience, Michael Sawyer

All Dissertations

Over the last 20 years the number of annual accidents in general aviation has seen a steady decline. The annual number of fatal accidents, however, has remained relatively stable. Adverse weather is consistently cited as a leading cause of fatal accidents in general aviation; weather accidents have a fatality rate nearly four times that of other general aviation accidents. Reviews of accident data reveal that often these accidents occur when inexperienced pilots who are certified only for visual flight rules flight continue into adverse weather. The Situation Assessment Hypothesis suggests these accidents occur when pilots fail to accurately recognize weather …

Go to article

Production And Characterization Of Novel Shaped Fibers For Fluid Sorption And Transport, Lisa Fuller Dec 2009

Production And Characterization Of Novel Shaped Fibers For Fluid Sorption And Transport, Lisa Fuller

All Dissertations

This work investigated the production and characterization of novel shaped fibers for fluid adsorption and transport. Shaped fibers such as Y, H, and octolobal, as well as conventional round fibers, were extruded using a research melt extruder. The fibers were extruded from 18 melt flow index (MFI) polypropylene (PP) and blends of 18 MFI PP and 400 MFI PP. Hydrophilic spin finish Bozzetto Favorol SF2 was applied to the surface of extruded fibers and hydrophilic polyester additive LB-100 was included in the blend of some H fibers to increase the hydrophilicity of the fiber surface. The geometric shape retention of …

Go to article

Hydrodynamics Of Freshwater Turtles: Maneuverability, Stability, And Effects Of Shell Shape, Gabriel Rivera Dec 2009

Hydrodynamics Of Freshwater Turtles: Maneuverability, Stability, And Effects Of Shell Shape, Gabriel Rivera

All Dissertations

Aquatic organisms exhibit tremendous diversity in body design and modes of propulsion that can strongly influence locomotor performance. Understanding how such differences affect locomotor performance is a major focus of research in integrative organismal biology and can provide insight into the evolutionary origins of such variation. Turtles are unique among extant tetrapods (i.e., amphibians, reptiles, birds, and mammals) in that they possess rigid bodies. In turtles, the vertebrae are fused dorsally with a bony carapace, precluding movement of the axial skeleton between the base of the neck and the tail. As a result of their immobilized axial skeleton and reduced …

Go to article

Measuring The Impact Of Varied Instructional Approaches In An Introductory Animal Science Course, Brian Bolt Dec 2009

Measuring The Impact Of Varied Instructional Approaches In An Introductory Animal Science Course, Brian Bolt

All Dissertations

The objectives of this project were to: evaluate the impact of demographic descriptors (gender, class rank and final grade) on student's self perceived level of engagement in classroom activities; measure the impact of varying teaching styles on a student's likelihood of correctly answering a knowledge based question and: assessing the relationship of knowledge acquisition with their level of engagement. Data were collected on students in the AVS 150, introductory animal science class (n=155) at Clemson University during the fall of 2008. Ten to fifteen minutes of class time were classified as conforming exclusively to one of three types of material …

Go to article

Sequence Analysis And Characterization Of The Dihydrodiol Dehydrogenase And Aldehyde Dehydrogenase Genes In'' Sphingomonas Paucimobilis'' Epa505, Jaleh Jalili Dec 2009

Sequence Analysis And Characterization Of The Dihydrodiol Dehydrogenase And Aldehyde Dehydrogenase Genes In'' Sphingomonas Paucimobilis'' Epa505, Jaleh Jalili

All Dissertations

A bacterial artificial chromosome (BAC) library was previously constructed from genomic DNA of Sphingomonas paucimobilis EPA505 at Clemson University Genomic institute (CUGI). To isolate and identify the bphB gene from the genome of S. paucimobilis EPA505, a set of primers was designed based on conserved regions of the bphB gene encoding dihydrodiol dehydrogenase of Sphingomonas CHY-1 and Sphingomonas yanoikuyae B1. Routine PCR was performed and a PCR fragment of approximately 500 bp that confirmed the presence of pbhB gene in Sphingomonas paucimobilis EPA505 was produced. Hybridization of the PCR product with BAC library was performed and one hundred two positive …

Go to article

Covalent Immobilization Of L1 Neural Cell Adhesion Molecule To Acrylated Tetronicâ® Hydrogels For Neural Regeneration, Rebecca Cribb Dec 2009

Covalent Immobilization Of L1 Neural Cell Adhesion Molecule To Acrylated Tetronicâ® Hydrogels For Neural Regeneration, Rebecca Cribb

All Dissertations

Spinal cord injuries cost the United States $20 billion per year, with an existing patient population of 256,000 growing by an estimated 12,000 each year. Current clinical therapies for spinal cord injury are limited to spinal immobilization and realignment via traction, surgery, administration of methylprednisolone sodium succinate (MPSS) within eight hours post-injury, and rehabilitation exercises. While these therapies are important and may minimize damage and restore limited function, there is a dire clinical need for treatments to address the growing population of chronically-injured patients.
Varying degrees of axonal regeneration and functional recovery following spinal cord injury have been achieved in …

Go to article

Field Evaluation Of The Immunocontraceptive Gonacontm In Reducing Eastern Gray Squirrel Fecundity In Urban Areas, Murali Pai Dec 2009

Field Evaluation Of The Immunocontraceptive Gonacontm In Reducing Eastern Gray Squirrel Fecundity In Urban Areas, Murali Pai

All Dissertations

The purpose of this study was to evaluate the immunocontraceptive GonaConTM in reducing fecundity in Eastern gray squirrel (EGS) (Sciurus carolinensis) in urban areas. Using a modified box trap design, 317 EGS were captured during four trapping sessions on a 5.66 ha site on Clemson University's main campus. EGS were handled using a restraint cone and sexed, weighed, ear-tagged and implanted with a microchip at the nape of the neck on all 'original' captures and later identified in subsequent captures as 'recaptures.' Blood samples and morphometric data were obtained on EGS before the immunocontraceptive GonaConTM was administered by …

Go to article

Prevalence And Biological Control Of Salmonella Contamination In Rendering Plant Environments And The Finished Rendered Meals, Brandon Kinley Dec 2009

Prevalence And Biological Control Of Salmonella Contamination In Rendering Plant Environments And The Finished Rendered Meals, Brandon Kinley

All Dissertations

Although the rendering process serves as invaluable means for the disposal of inedible animal by-products, the finished products often harbor pathogenic and opportunistic microorganisms such as Salmonella and enterococci, respectively. The temperatures used during the rendering process far exceed the heat tolerance threshold of most bacterial species, so cross-contamination from the environment and/or from the incoming raw material is the proposed source of the contamination. Research has demonstrated that the raw material coming into the rendering facility is highly contaminated with pathogenic bacteria including Salmonella. While not in a rendering facility, studies have also demonstrated that bacteria such as Salmonella …

Go to article

Characterization Of Escherichia Coli Related To Construction Site Sediment Basins, Calvin Sawyer Dec 2009

Characterization Of Escherichia Coli Related To Construction Site Sediment Basins, Calvin Sawyer

All Dissertations

Large construction sites can have significant temporary and permanent impacts on the physical landscape. Excess sediment is frequently deposited into nearby surface waters, altering benthic habitat, reducing water clarity and transporting other pollutants such as enteric bacteria. To capture eroded soil and attenuate storm discharge peaks, many permitted construction projects larger than 10 acres in South Carolina require the installation of a sediment basin. Sediment-laden runoff is routed to a newly excavated impoundment, where larger particles settle out of suspension. Thus an entirely new hydrologic feature designed to concentrate eroded sediment and water is introduced into the landscape.
Eight construction …

Go to article

Creation Of Bioactive Surfaces To Modulate Cell Behavior Using Surface Initiated Photoiniferter-Mediated Graft Photopolymerization, Nihar Shah Dec 2009

Creation Of Bioactive Surfaces To Modulate Cell Behavior Using Surface Initiated Photoiniferter-Mediated Graft Photopolymerization, Nihar Shah

All Dissertations

Biomaterials widely used in biomedical applications still face biocompatibility issues arising from non-specific protein adsorption on the foreign surface, and the consequent undesired cell response. Emerging evidence suggests that imparting specific bioactivity to the biomaterial's surface to elicit favorable response from cells, (like osseointegration of joint implants and endothelialization of stents) can yield much better biocompatibility results when combined with passive prevention of protein adsorption. In more complex diseases like spinal cord injury and cardiomyopathy, specific biomolecules are required to elicit desired cell responses for successful regeneration. However, for success of such biomolecule based strategies, the effects of various parameters …

Go to article

Observations Of Badgers Preying On Black-Tailed Prairie Dogs, Daniel S. Licht Dec 2009

Observations Of Badgers Preying On Black-Tailed Prairie Dogs, Daniel S. Licht

The Prairie Naturalist

American badgers (Taxidea taxus) often visit black-tailed prairie dog (Cynomys ludovicianus) colonies, most likely in search of prey (Lomolino and Smith 2004, Shaughnessy and Cifelli 2004). Badgers are well suited to hunting fossorial prey such as prairie dogs by excavating burrows and capturing individuals belowground (Lindzey 2003). However, the ecological literature is sparse regarding details of how badgers hunt and capture prairie dogs underground. Eads and Biggins (2008) documented three occurrences of a badger excavating prairie dogs. That badger (apparently the same individual) had a den within the prairie dog town where captures occurred. This note …

Go to article

Mortality Of Cranes (Gruidae) Associated With Powerlines Over A Major Roost On The Platte River, Nebraska, Gregory D. Wright, Timothy J. Smith, Robert K. Murphy, Jeffery T. Runge, Robert R. Harms Dec 2009

Mortality Of Cranes (Gruidae) Associated With Powerlines Over A Major Roost On The Platte River, Nebraska, Gregory D. Wright, Timothy J. Smith, Robert K. Murphy, Jeffery T. Runge, Robert R. Harms

The Prairie Naturalist

Two 69-kilovolt powerlines spanning the Platte River in south central Nebraska are suspected to cause substantial mortality to sandhill cranes (Grus canadensis) and pose a threat to endangered whooping cranes (G. americana) that roost overnight on the river during spring and fall migrations. Most studies of crane collisions with powerlines in the region have focused on counts of carcasses away from night roosts on the river and none have accounted for potential biases in detecting carcasses. We found 61 carcasses of sandhill cranes below over-river segments of the two powerlines during 4 March to 7 April …

Go to article

Bed Site Selection Of Fawn Pronghorn In Custer State Park, South Dakota, Chad P. Lehman, Jamin D. Hartland, Barbara J. Keller, Joshua J. Millspaugh, Gary C. Brundige Dec 2009

Bed Site Selection Of Fawn Pronghorn In Custer State Park, South Dakota, Chad P. Lehman, Jamin D. Hartland, Barbara J. Keller, Joshua J. Millspaugh, Gary C. Brundige

The Prairie Naturalist

We evaluated pronghorn (Antilocapra americana) fawn bedding site characteristics on a prairie and ponderosa pine (Pinus ponderosa) landscape interface in Custer State Park, South Dakota. We radio-marked 16 adult female pronghorn and collected bed site information from their fawns during 2007~2008. We compared bed site selection with random sites (n = 74) during 2 periods; the early hiding phase when fawns were 1 ~28 days of age (n = 23 bed sites) and the later group phase when fawns were 29~60 days of age (n = 52 bed sites). During the hiding phase fawns selected dry …

Go to article

Beautifying The Ugly Step-Sister: Desiging An Effective Cap-And-Trade Program To Reduce Greenhouse Gas Emissions, Miles Young Dec 2009

Beautifying The Ugly Step-Sister: Desiging An Effective Cap-And-Trade Program To Reduce Greenhouse Gas Emissions, Miles Young

BYU Law Review

No abstract provided.

Go to article

The Hard Embodiment Of Culture, Dov Cohen, Angela K. Y. Leung Dec 2009

The Hard Embodiment Of Culture, Dov Cohen, Angela K. Y. Leung

Research Collection School of Social Sciences

The way humans move and comport their bodies is one way they (literally) carry their culture. In pre-wired embodiments, body comportment triggers basic, evolutionarily prepared affective and cognitive reactions that subsequently prime more complex representations. Culture suffuses this process, because (1) cultural artifacts, affordances, and practices make certain body comportments more likely, (2) cultural practices, rituals, schemas, and rules promote the learning of an otherwise underspecified connection between a given body comportment and a particular basic reaction, and (3) cultural meaning systems elaborate basic affective and cognitive reactions into more complex representations. These points are illustrated with three experiments that …

Go to article

Water Resources Year In Review - Winter 2009 Vol 21. No 2, Annis Water Resources Institute Dec 2009

Water Resources Year In Review - Winter 2009 Vol 21. No 2, Annis Water Resources Institute

AWRI Reviews

No abstract provided.

Go to article

Discovering Metabolic Networks Of Bovine Fertilization, Erin Lynn Young Dec 2009

Discovering Metabolic Networks Of Bovine Fertilization, Erin Lynn Young

Undergraduate Honors Capstone Projects

At the time of fertilization, a dramatic change occurs in the oocyte that transforms this cell from a metaphase arrested state into a metabolically active and dynamic state. The view of the flow of biological processes within organisms has recently shifted from that of a linear path to a more complex network. Biological processes are no longer thought of in the simple terms of DNA to RNA, RNA to proteins, and proteins to final activity. It is now known that many biological processes involve interconnected networks and feedback loops in which DNA, RNA, proteins, and metabolites perform specific roles. We …

Go to article

First Prev Next Last