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Corrosion Dynamics Of Cobalt-Chromium Alloy F-75 Powder, Tedman Tong

Master's Theses

The increasing usage of metal-on-metal joint replacements consisting of a cobalt-chromium-molybdenum alloy requires increasing concern regarding the inevitable generation of metallic wear debris. Patients with these joint replacements exhibit elevated concentrations of cobalt and chromium ions within their serum, blood and urine. The presence of these metal ions suggests the potential for bodily damage and indicates corrosive processes are acting upon wear debris.

To understand the behavior of these corrosive processes, powders of cobalt-chromium-molybdenum alloy F-75 were studied. Four powder sizes (44, 74, 105, and 420 µm diameter) were subjected to Hank’s Balanced Salt Solution (HBSS) for a 42 day …

Spatial And Temporal Temperature Distributions In Municipal Solid Waste Landfills, James L. Hanson, Nazli Yesiller, Nicolas K. Oettle

Civil and Environmental Engineering

Long-term spatial and temporal variations in temperatures have been investigated in covers, wastes, and liners at four municipal solid waste landfills located in different climatic regions: Alaska, British Columbia, Michigan, and New Mexico. Temperatures were measured in wastes with a broad range of ages from newly placed to old (up to 40 years). The characteristic shape of waste temperature versus depth relationships consisted of a convex temperature profile with maximum temperatures observed at central locations within the middle third fraction of the depth of the waste mass. Lower temperatures were observed above and below this central zone, with seasonal fluctuations …

Sierra Nevada Red Fox (Vulpes Vulpes Necator): A Conservation Assessment, John D. Perrine, Lori A. Campbell, Gregory A. Green

Biological Sciences

One goal of the Sierra Nevada Forest Plan Amendment (SNFPA) 2001 and 2004 Records of Decision was to protect and recover native Sierra Nevada red fox (Vulpes vulpes necator) populations in the Sierra Nevada (USDA Forest Service 2001 p. 14). To accomplish this goal, the ROD commits the U.S. Department of Agriculture (USDA) Forest Service to completing a conservation assessment for the Sierra Nevada red fox in cooperation with other federal, state, and local agencies, as well as Tribal governments. This conservation assessment synthesizes the best available scientific information and thought concerning habitat relationships, population status and trends, historical and …

Turning Crocodilian Hearts Into Bird Hearts: Growth Rates Are Similar For Alligators With And Without Right-To-Left Cardiac Shunt, John Eme, June Gwalthney, Tomasz Owerkowicz, Jason M. Blank, James W. Hicks

Biological Sciences

The functional and possible adaptive significance of non-avian reptiles’ dual aortic arch system and the ability of all non-avian reptiles to perform central vascular cardiac shunts have been of great interest to comparative physiologists. The unique cardiac anatomy of crocodilians – a four-chambered heart with the dual aortic arch system – allows for only right-to-left (R–L; pulmonary bypass) cardiac shunt and for surgical elimination of this shunt. Surgical removal of the R–L shunt, by occluding the left aorta (LAo) upstream and downstream of the foramen of Panizza, results in a crocodilian with an obligatory, avian/mammalian central circulation. In this study, …

Meiotic Insurance: Designing A System To Study Crossover Control In Yeast, Kate V. Karfilis

Master's Theses

Meiosis is a specialized form of cell division in which haploid gametes are produced from diploid progenitors. This reduction in ploidy results from proper meiotic chromosome segregation and is ensured by crossover recombination events. Given their importance, it is no surprise that crossover formation is regulated in most eukaryotes. Crossover assurance is a regulatory mechanism that helps to ensure that each pair of chromosomes gets at least one crossover during meiosis.

We seek to better understand how crossover assurance works. To do so, we have developed a system in which crossover formation between a pair of chromosomes is restricted to …

Integration Of Microfluidics With Surface Plasmon Resonance, Scott B. Fratzke

Master's Theses

This thesis successfully integrates laminate microfluidic devices with an analytic Surface Plasmon Resonance (SPR) instrument. Integration was accomplished at low-cost using materials such as polydimethylsiloxane (PDMS), Poly(methyl methacrylate) (PMMA), Tygon tubing, and a 3-way stopcock. The main components of this thesis are the design and fabrication of the low-cost, in-house fluidics that can integrate with upstream microfluidics and the validation of the in-house fluidics using the Biosensing Instruments BI-2000 SPR instrument. The low-cost fluidics was designed and fabricated “in-house” using a novel investment casting technique that required the use of laser cutting technology to make a master cast, and candle …

Immunohistochemical Mapping Of Hypoxia In Ischemic Mouse Hindlimb Skeletal Muscle, Emily Deckert

Biomedical Engineering

The study of blood vessel growth and remodeling is a complex endeavor. Hypoxia, the lack of oxygen in a tissue, is known to stimulate angiogenesis (the growth of new blood vessels), and have little effect on arteriogenesis (the enlargement of existing blood vessels). However, the role of hypoxia in vessel function is unknown, but may be determined using the results and methods developed in this experiment.

Supplied by the bloodstream, oxygen is required by all cells and tissues to remain healthy. If the bloodstream supplying a certain tissue with blood is disrupted, the tissue becomes ischemic, often leading to hypoxia. …

Barnacle Settlement And The Adhesion Of Protein And Diatom Microfouling To Xerogel Films With Varying Surface Energy And Water Wettability, John A. Finlay, Stephanie M. Bennett, Lenora H. Brewer, Anastasiya Sokolova, Gemma Clay, Nikhil Gunari, Anne E. Meyer, Gilbert C. Walker, Dean E. Wendt, Maureen E. Callow, James A. Callow, Michael R. Detty

Biological Sciences

Previous work has shown that organosilica-based xerogels have the potential to control biofouling. In this study, modifications of chemistry were investigated with respect to their resistance to marine slimes and to settlement of barnacle cyprids. Adhesion force measurements of bovine serum albumin (BSA)-coated atomic force microscopy (AFM) tips to xerogel surfaces prepared from aminopropylsilyl-, fluorocarbonsilyl-, and hydrocarbonsilyl-containing precursors, indicated that adhesion was significantly less on the xerogel surfaces in comparison to a poly(dimethylsiloxane) elastomer (PDMSE) standard. The strength of adhesion of BSA on the xerogels was highest on surfaces with the highest and the lowest critical surface tensions, gamma(C) and …

Designing Thematic Instruction With Authentic Resources: Science And Technology, Brian G. Kennelly

World Languages and Cultures

No abstract provided.

Tribological Comparison Of Traditional And Advanced Firearm Coatings, Greg Boban

Master's Theses

The objective of this project is to find which type of coating has the best performance characteristics for finishing firearms. This is accomplished by measuring and comparing several performance characteristics, such as: adhesion, hardness, wear resistance, friction control, and corrosion resistance. Appearance is not a factor since any exterior coating that is flashy can be subdued or camouflaged with special purpose paints, which have proven durable enough for such purposes. Cost will not be a limiting factor for this experiment, but will be discussed in the conclusion as a secondary concern. This data will be used to identify the best …

A Comparison Of Analytical Methods For Quantifying Denatured Whey Proteins And Their Correlation To Solubility, Michelle D. Allen

Master's Theses

Protein structure affects the bioactivity and functionality of whey protein ingredients in food systems. Bioactivity of whey proteins and their derivatives are highly dependent upon primary, secondary and tertiary structure. The degree of denaturation of whey proteins is an important factor for determining how whey protein ingredients will perform in a food system. Several analytical methods have been developed to quantify protein denaturation of whey proteins. The goal of this project was to use a variety of analytical methods to quantify whey protein denaturation and to evaluate the correlation of denaturation to the functionality of whey protein powders.

The objective …

Grand Challenges In Comparative Physiology: Integration Across Disciplines And Across Levels Of Biological Organization, Donald L. Mykles, Cameron K. Galambor, Jonathon H. Stillman, Lars Tomanek

Biological Sciences

No abstract provided.

Effects Of Testosterone And Captivity On Medial And Dorsal Cortex Volumes And Neurogenesis In Adult Male Western Fence Lizards, Sceloporus Occidentalis, D. R. Pfau, S. Y. Potter, D. F. Denardo, E. N. Taylor, C. R. Strand

Biological Sciences

In lizards, the medial cortex and dorsal cortex are thought to be homologous to the hippocampus in birds and mammals, in that these regions are functionally involved with spatial memory and learning. In birds and mammals, neurogenesis continues into adulthood in these regions and is associated with ability of spatial memory tasks. Little is known about whether adult neurogenesis contributes to memory formation or spatial memory in lizards. In some lizards, territory size is correlated with testosterone (T) levels. If T affects these brain regions to help with spatial navigation, manipulating T levels may influence the medial or dorsal cortex …

Proteomic Analysis Of The Purple Sea Urchin, Strongylocentrotus Purpuratus, In Response To Acute Heat Stress, M. W. Webb, M. Devian, L. Tomanek

Biological Sciences

No abstract provided.

The Proteomic Response Of Mytilus Galloprovincialis And M. Trossulus To Acute Temperature Stress, Lars Tomanek, Marcus Zuzow

Biological Sciences

No abstract provided.

The Malta Cistern Mapping Project: Underwater Robot Mapping And Localization Within Ancient Tunnel Systems, Cory White, Daniel Hiranandani, Christopher S. Olstad, Keith Buhagiar, Timmy Gambin, Christopher M. Clark

Computer Science and Software Engineering

This paper documents the development of an underwater robot system enabled with several mapping and localization techniques applied to a particular archaeological expedition. The goal of the expedition was to explore and map ancient cisterns located on the islands of Malta and Gozo. The cisterns of interest acted as water storage systems for fortresses, private homes, and churches. Such cisterns often consisted of several connected chambers, still containing water. A sonar-equipped remotely operated vehicle (ROV) was deployed into these cisterns to obtain both video footage and sonar range measurements. Six different mapping and localization techniques were employed, including (1) sonar …

Implementation Of Physiologic Pressure Conditions In A Blood Vessel Mimic Bioreactor System, Kevin Mark Okarski

Master's Theses

ABSTRACT

Implementation of Physiologic Pressure Conditions in a Blood Vessel Mimic Bioreactor System

Kevin Mark Okarski

Tissue engineering has traditionally been pursued as a therapeutic science intended for restoring or replacing diseased or damaged biologic tissues or organs. Cal Poly’s Blood Vessel Mimic Laboratory is developing a novel application of tissue engineering as a tool for the preclinical evaluation of intravascular devices. The blood vessel mimic (BVM) system has been previously used to assess the tissue response to deployed stents, but under non-physiologic conditions. Since then, efforts have been made to improve the vessel and bioreactor’s ability to emulate in …

Determining The Fate Of Hybridized Genomes In The Allopolyploid Brassica Napus, Tina Y. Wang

Master's Theses

Polyploidy is widely acknowledged as a widespread mechanism in the evolution and speciation of the majority of flowering plants. Allopolyploid forms through interspecific hybridization and whole genome duplication. While allopolyploids may display increased vigor relative to their progenitors, they can also face challenges to fertility following hybridization. Genetic changes in allopolyploids result from recombination between the hybridized subgenomes, which can influence phenotype and ultimately determine fitness of future generations. To study dynamic changes that follow allopolyploid formation, Brassica napus lineages were derived by hybridizing Brassica oleracea and Brassica rapa. Two lineages of B. napus were analyzed for genetic and phenotypic …

Diurnal Rhythms Of Behavior And Brain Mrna Expression For Arginine Vasotocin, Isotocin, And Their Receptors In Wild Amargosa Pupfish (Cyprinodon Nevadensis Amargosae), Sean C. Lema, Lauren J. Wagstaff, Nina M. Gardner

Biological Sciences

Amargosa pupfish (Cyprinodon nevadensis amargosae) occupy remote desert habitats that vary widely in environmental conditions from day to night. In this study, die! patterns of behavior were documented for pupfish in their natural habitat, and examined relative to changes in the abundance of mRNAs encoding prepro-arginine vasotocin (pro-VT), prepro-isotocin (pro-IT), three distinct vasotocin receptors (V1a1, V1a2, and V2), and an isotocin receptor (ITR) in the brain. The behavior of wild pupfish varied diurnally, with frequent aggression from 12:00 to 15:00 h and courtship and spawning most common between 15:00 and 19:00h. Transcript abundance for pro-VT in the brain …

Low Vitamin D Status Is Associated With Physical Inactivity, Obesity And Low Vitamin D Intake In A Large Us Sample Of Healthy Middle-Aged Men And Women, K. Brock, W. Y. Huang, D. R. Fraser, L. Ke, M. Tseng, R. Stolzenberg-Solomon, U. Peters, J. Ahn, M. Purdue, R. S. Mason, C. Mccarty, R. G. Ziegler, B. Graubard

Kinesiology and Public Health

The aim of this study was to investigate modifiable predictors of vitamin D status in healthy individuals, aged 55–74, and living across the USA. Vitamin D status [serum 25-hydroxyvitamin D (25(OH)D)] was measured along with age and season at blood collection, demographics, anthropometry, physical activity (PA), diet, and other lifestyle factors in 1357 male and 1264 female controls selected from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO) cohort. Multivariate linear and logistic regression analyses were used to identify associations with vitamin D status. Three%, 29% and 79% of the population had serum 25(OH)D levels 30 kg/m^{2 …}

Ant Colony Optimization Algorithm For Robot Path Planning, Michael Brand, Michael Masuda, Nicole Wehner, Xiao-Hua Yu

Electrical Engineering

Path planning is an essential task for the navigation and motion control of autonomous robot manipulators. This NP-complete problem is difficult to solve, especially in a dynamic environment where the optimal path needs to be rerouted in real-time when a new obstacle appears. The ACO (Ant Colony Optimization) algorithm is an optimization technique based on swarm intelligence. This paper investigates the application of ACO to robot path planning in a dynamic environment. Two different pheromone re-initialization schemes are compared and computer simulation results are presented.

Dairy Science Professor Named Cal Poly Distinguished Scholar, Public Affairs Office

Press Releases

No abstract provided.

Bioinformatics Data Mining Using Artificial Immune Systems And Neural Networks, Shane Dixon, Xiao-Hua Yu

Electrical Engineering

Bioinformatics is a data-intensive field of research and development. The purpose of bioinformatics data mining is to discover the relationships and patterns in large databases to provide useful information for biomedical analysis and diagnosis. In this research, algorithms based on artificial immune systems (AIS) and artificial neural networks (ANN) are employed for bioinformatics data mining. Three different variations of the real-valued negative selection algorithm and a multi-layer feedforward neural network model are discussed, tested and compared via computer simulations. It is shown that the ANN model yields the best overall result while the AIS algorithm is advantageous when only the …

How Do Polar Marine Ecosystems Respond To Rapid Climate Change?, Oscar Schofield, Hugh W. Ducklow, Douglas G. Martinson, Michael P. Meredith, Mark A. Moline, William R. Fraser

Biological Sciences

Climate change will alter marine ecosystems; however, the complexity of the food webs, combined with chronic undersampling, constrains efforts to predict their future and to optimally manage and protect marine resources. Sustained observations at the West Antarctic Peninsula show that in this region, rapid environmental change has coincided with shifts in the food web, from its base up to apex predators. New strategies will be required to gain further insight into how the marine climate system has influenced such changes and how it will do so in the future. Robotic networks, satellites, ships, and instruments mounted on animals and ice …

Two Cal Poly Faculty Members To Receive The University’S Annual Distinguished Scholarship Award, Public Affairs Office

Press Releases

No abstract provided.

Dairy Science, History Professors Receive Annual Distinguished Scholarship Award, Public Affairs Office

Press Releases

No abstract provided.

Identification Of Multiple Vasotocin Receptor Cdnas In Teleost Fish: Sequences, Phylogenetic Analysis, Sites Of Expression, And Regulation In The Hypothalamus And Gill In Response To Hyperosmotic Challenge, Sean C. Lema

Biological Sciences

Vasopressin and its homolog vasotocin regulate hydromineral balance, stress responses, and social behaviors in vertebrates. In mammals, the functions of vasopressin are mediated via three classes of membrane-bound receptors: V1a-type, V1b-type and V2-type. To date, however, only a single class of vasotocin receptor has been identified in teleost fish. Here, cDNAs encoding three putative vasotocin receptors – two distinct V1a-type receptor paralogs (V1a1 and V1a2) and a previously undescribed V2- type receptor (V2) – and a single isotocin receptor were isolated and sequenced from the Amargosa pupfish (Cyprinodon nevadensis amargosae). RT-PCR revealed that mRNAs …

Ocean Currents Help Explain Population Genetic Structure, Crow White, Kimberly A. Selkoe, James Watson, David A. Siegel, Danielle C. Zacherl, Robert J. Toonen

Biological Sciences

No abstract provided.

Mustang Daily, June 3, 2010

Cal Poly Student Newspaper

Student newspaper of California Polytechnic State University, San Luis Obispo, CA.

Mustang Daily, June 2, 2010

Cal Poly Student Newspaper

Student newspaper of California Polytechnic State University, San Luis Obispo, CA.