Now showing items 5800-5819 of 15426

    • Extracellular Lung Immunomodulatory Proteins and Their Involvement in the Development of COPD

      Ledford, Julie G.; Bui, Mylinh; Polverino, Francesca; Romanoski, Casey (The University of Arizona., 2020)
      More than 250 million people worldwide are currently diagnosed with Chronic Obstructive Pulmonary Disease (COPD). COPD is a broad classification of clinical phenotypes that include but is not limited to, emphysema, chronic bronchitis, asthma- COPD overlap syndrome, and early-COPD. Patients with COPD presents with persistent respiratory symptoms and airflow limitation. One of the leading risk factors of COPD is cigarette smoke, which has been associated with triggering immune and inflammatory responses in the respiratory system. Upon review of the current literature, there is evidence of altered production and activity of key immunomodulatory lung proteins due to cigarette smoke that could contribute to the development of COPD. This thesis will review two predominant immunomodulatory lung proteins, club cell secretory protein (CC16) and pulmonary surfactant protein A (SP-A), in order to provide novel insights into the development of COPD to improve future surveillance and treatment for patients who are at risk or diagnosed with the disease.
    • Extracellular Matrix Induced Drug Resistance and Tumor Survival in Prostate Cancer

      Miranti, Cynthia; Varghese, Reeba P.; Cress, Anne E.; Gordon, Herman (The University of Arizona., 2018)
      Castration-resistant prostate cancer (CRPC) often develops in patients that fail to respond to androgen deprivation therapy (ADT). Patients with CRPC have a low survival rate and understanding its mode of drug resistance is vital in the development of therapeutic agents to treat CRPC. CRPC also demonstrates resistance to specific inhibitors such as PI3K inhibitors. The extracellular matrix has been implicated in promoting drug resistance in various cancers. Prior studies indicate that adhesion to laminin promoted drug resistance in an androgen receptor (AR) dependent manner. However, due to the copious amount of collagen found throughout the body, especially in the bone where CRPC metastases are preferentially localized, I hypothesized that collagen induces drug resistance in prostate cancer. PC-3 Puro, PC-3 AR1, PC-3 AR2, and C4-2 cells adhered to laminin or collagen were treated with PI3K inhibitors (LY294002 or PX-866). Resistance to the drug was monitored via cell death assay that examined cell viability status by trypan blue exclusion. Prostate cancer cells adhered to collagen demonstrated resistance against LY294002 and PX-866 in an AR independent manner. Immunoblot analysis indicated a collagen induced upregulation of MRP1 and MCL-1, which was blocked by AR. Treatment with S63845, an MCL-1 inhibitor, re-sensitized the cells to PX-866 and LY294002. Collectively, these results indicate collagen induces drug resistance in prostate cancer cells in an AR independent manner. However, further analysis is required to determine the precise mechanism that upregulates MCL-1 and MRP1 in collagen-induced drug resistance.
    • Extracellular Mitochondria in Sepsis-Induced Acute Respiratory Distress Syndrome

      Wong, Raymond K.; Satterlee, Taylor; Fox, Kenneth A.; Chen, Qin M. (The University of Arizona., 2020)
      Sepsis-induced acute respiratory distress syndrome (ARDS) is a life threatening disease that is associated with high mortality rates, and high hospital costs. The body’s widespread and aggressive inflammatory response to infection plays a central role in this condition, as it results from a rampant generation of inflammatory cytokines and reactive oxygen species in response to pathogen associated molecular patterns (PAMPs) and damage associated molecular patterns (DAMPs). Despite the seriousness of this condition, successful treatment strategies and effective biomarkers remain elusive. Here we aim to mimic a state of sepsis-induced ARDS in vitro and examine the response of extracellular mitochondria under these conditions. Additionally we aim to examine the proteomic profile of the extracellular mitochondrial pellet in a state of oxidative stress compared to control. Finally we aim to demonstrate that extracellular mitochondria are present in an in vivo model of sepsis-induced ARDS using a porcine model. From this work we are able to conclude that cells release mitochondrial DNA in response to both lipopolysaccharide and hydrogen peroxide treatments, however the mechanism by which this occurs remains unclear. Extracellular mitochondrial DNA is also present in an in vivo porcine sepsis-induced ARDS model. From proteomic analysis of the extracellular mitochondrial pellet by liquid chromatography - mass spectrometry, we found 16 proteins to be significantly (P<0.10) up-regulated and 2 proteins to be significantly down-regulated. We hope to apply the profile of extracellular mitochondria we have built to eventually identify a novel biomarker of sepsis-induced ARDS.
    • Extraction and analysis of the hemicellulose fractions of mesquite leaves

      Ester, Virginia Charlotte, 1908- (The University of Arizona., 1938)
    • The extraction of gold from special flotation concentrates

      Houghton, Neal Doyle, 1916- (The University of Arizona., 1939)
    • The extraction of molybdenum from wulfenite concentrates by a leaching method

      Holmes, Donald Thomas, 1913- (The University of Arizona., 1935)
    • The extraction of polyribisomes [sic] from lyophilized cells of Saccharomyces cerevisiae

      Kelley, Robert Ernest, 1944- (The University of Arizona., 1968)
    • Extraction of Pre-Blast Rock Fracture Information From 3D Point Cloud of Post- Blast Fragmentation

      Kemeny, John M.; Wang, Yunkun; Kim, Kwangmin; Momayez, Moe (The University of Arizona., 2020)
      Muck piles, obtained by mining blasting operations, contain a huge amount of rock fragments. Surfaces of the post-blast rock fragments consist of pre-blast (in-situ) fractures and post-blast (blasting induced) fractures. As the remaining parts of in-situ joints, pre-blast fractures include clues of joint information inside rock masses. By extracting the tremendous amount of the clues sealed in muck piles, a better knowledge of the inner structures of rock masses can be realized, which is very meaningful to rock mass characterization, blasting effect evaluation and further blasting design. In order to extract the clues and collect in-situ joint information, differentiating pre-blast fractures from post-blast fractures is the first and vital step, which is also the focus of the research in this thesis. We investigated topographic differences between pre-blast fractures and post-blast fractures by studying the point cloud data of individual rock fragments. 3D point cloud data of the fragment fracture surfaces were generated by photogrammetry. Geometrical information of the fracture surfaces was extracted from the point cloud data and analyzed using three methods, referred to as the RMS method, the area ratio method and the Fourier transform analysis method. The following steps were taken to investigate the fracture surfaces: (1) 33 post-blast rock fragment samples were collected from the University of Arizona San Xavier Mine. 100 real fractures were selected from the 33 samples. 3D point cloud models of the real fractures were generated via photogrammetry. By observing and comparing the surfaces of the 100 real fractures, they were classified into three groups: pre-blast fractures (23 fractures), post-blast fractures (61 fractures), and fractures containing rock bridges (16 fractures). Typical surface topographic patterns (Flat, U-shape, Sine-shape, Saw-shape, Trapezoid-shape, and Battlement-shape) were utilized to develop the simplified fracture models. The functional formulas and 3D point clouds of the simplified fracture models were then generated. (2) The raw data of the real fractures were edited in point cloud processing software before further analysis. The data processing work mainly includes fracture segmenting, fracture projecting and profile extracting. (3) The application of the RMS, area ratio and Fourier transform analysis methods were presented as a sensitivity analysis on the simplified fracture model data and validated against the real fracture data. The simplified fracture model data were utilized for a sensitivity analysis of the RMS and area ratio methods. The real fracture data were tested by all three methods and the test results were compared with the classification results. The results show that: (1) RMS is sensitive to surface amplitude change. If a fracture surface has greater undulation, it tends to have higher RMS value. Pre-blast fractures have a much gentler undulating surface than post-blast fractures. (2) Area ratio is sensitive to surface wavenumber change. If a fracture surface has denser undulation (shorter wavelength), it tends to have higher area ratio value. Pre-blast fractures have much sparser undulating surfaces than post-blast fractures. (3) Investigating geometrical features using the Fast Fourier Transform (FFT) considers both peak wavenumbers and amplitudes. Pre-blast fractures and post-blast fractures have very similar undulation patterns (range of wavelengths), but undulation intensity (amplitude) of pre-blast fractures is much gentler at the same wavelength. The wavenumber peak trendline of rock bridges has a relatively round turning angle, compared to the trendlines for pre-blast and post-blast fractures.

      Simonzadeh, Ninus. (The University of Arizona., 1982)
    • Extrinsic silicon detector characterization

      Dereniak, Eustace L.; Garcia, John Phillips, 1956- (The University of Arizona., 1990)
      A gallium doped extrinsic silicon (Si:Ga) photoconductive detector was tested for sensitivity and quickness of response. The developmental goal for this detector material was high speed operation without compromised detectivity (D*). The high speed, p-type infrared photoconductor, with photoconductive gain less than unity, was tested at 10.5 μm to determine an experimental value for the detectivity-bandwidth product of D*f* = 3.8 x 10¹⁸ cm-Hz³/²/W. Subsequently a theoretical model taking into account the optical absorption profile and majority carrier transport processes within the detector was developed which agreed with the experimental data.
    • Eye lens weight as an indicator of age in the collared peccary (Pecari tajacu)

      Richardson, Gary Lemonte, 1942- (The University of Arizona., 1966)
    • The F.O.B. cost of marketing desert citrus fruit

      Dobbins, C. E. (Claude Edwin), 1917- (The University of Arizona., 1949)
    • Fabrication and investigation of GaAsP light emitting diodes

      Salzman, James Donald, 1931- (The University of Arizona., 1972)
    • Fabrication and modeling of a floating-gate transistor for use as an electrostatic-discharge detector

      Schrimpf, Ron D.; Hsueh, Weichung Paul, 1962- (The University of Arizona., 1988)
      Electrostatic discharge is of great concern to the electronics industry. It degrades and destroys large numbers of integrated circuits at every step from fabrication through packaging and testing. The goal of this research effort was the development of a device that can be used to obtain quantitative information on electrostatic discharge (ESD) in the integrated-circuit workplace. The device that was developed can be utilized in two different modes. (1) It can be used to form ESD test wafers or test chips. (2) It can be incorporated on product chips to give the ESD history of devices or monitor the process line. The technology that was examined in this work was that for floating-gate PROMS. A simple analytical model for obtaining a parameter called the ESD factor was developed. The prototype detector was designed, fabricated and tested in the Semiconductor Processing Facility of the University of Arizona. Evidence will be presented that the FLOTOX type of EEPROM functions well in its application as an ESD detector.
    • Fabrication and Testing of Computer Generated Holograms Using the MLA 150

      Milster, Thomas D.; Purvin, Kira; Kim, Daewook; Kim, Youngsik (The University of Arizona., 2021)
      Grayscale lithography is a powerful technique that makes it possible to fabricate three-dimensional microstructures in photoresist. This thesis presents a newly developed process for achieving high quality grayscale lithography using the MLA 150 as well as initial results for various applications. Multiple photoresists including S1813, S1827 and AZ P4620 are characterized to provide a foundation for the developed fabrication process. A linearization regime is also presented that calibrates the MLA 150’s nominal grayscale output such that a result displaying equally spaced gray layers is achieved. The final grayscale lithography process is applied to fabricate a computer generated hologram (CGH) for use in adaptive optics for phase retrieval. A replication process is detailed that enables the exposed patterns to be replicated in NOA61 to form a usable and semi-permanent optical element. Comparisons made between the fabricated optical elements and the original designs demonstrate the success of the fabrication process.
    • Fabrication of a micro-Fresnel lens on a spherical substrate

      Milster, Thomas D.; Trusty, Robert Mason, 1959- (The University of Arizona., 1990)
      A decrease in the size and weight of the objective lens in an optical data storage system (ODS) would improve performance. Limits on reducing the lens size were investigated. Size reduction is limited by aberrations introduced by the disk cover plate that protects the recording medium from dust and scratches. Size reduction is also limited by off-axis aberrations introduced by beam tilt required to maintain a field of view similar to conventional ODS objectives. It was shown that a Fresnel microlens on a thin spherical shell is acomatic for all field angles. A technique used to fabricate such a lens was demonstrated. The resulting lens was presented.
    • Fabrication of micro-optics using binary and graylevel masks

      Descour, Michael; Simon, Daniel I, 1971- (The University of Arizona., 1998)
      This thesis provides step by step instructions on how to design, layout, and fabricate diffractive optical elements (DOE). While there has been a great deal published on the design of DOEs, there are few publications detailing how to transform a design into a physical element. The thesis describes how to order a photomask and pattern an element. It provides recipes that I have used to etch DOEs with both an ion mill and a reactive ion etcher (RIE) at the Optical Sciences Center. The thesis includes characterization of the elements fabricated using these recipes. In addition the thesis looks at the design and fabrication of ring toric lenslets. A ring toric lenslet is a DOE that focuses light to a ring instead of a point. The ring toric lenslet has potential applications in the optical data storage industry. This thesis includes macros for the design and mask layout of binary and grayscale ring toric lenslets. Grayscale elements require special design, calibration, and mask layout steps not necessary for binary elements. Details of the design, calibration, mask layout, and fabrication of the grayscale element are included.
    • Fabrication of Polystyrene Core-Silica Shell Nanoparticles for Scintillation Proximity Assay (SPA) Biosensors

      Aspinwall, Craig A.; Noviana, Eka; Heien, Michael L.; Pyun, Jeffrey (The University of Arizona., 2015)
      The development of analytical tools for investigating biological pathways on the molecular level has provided insight into diseases and disorders. However, many biological analytes such as glucose and inositol phosphate(s) lack the optical or electrochemical properties needed for detection, making molecular sensing challenging. Scintillation proximity assay (SPA) does not require analytes to possess such properties. SPA uses radioisotopes to monitor the binding of analytes to SPA beads. The beads contain scintillants that emit light when the radiolabeled analytes are in close proximity. This technique is rapid, sensitive and separation-free. Conventional SPA beads, however, are large relative to the cells and made of hydrophobic organic polymers that tend to aggregate or inorganic crystals that sediment rapidly in aqueous solution, thus limiting SPA applications. To overcome these problems, polystyrene core-silica shell nanoparticles (NPs) doped with pTP and dimethyl POPOP were fabricated to produce scintillation NPs that emit photons in the blue region of visible light. The developed scintillation particles are approximately 250 nm in diameter (i.e. 200 nm of core diameter and 10-30 nm of shell thickness), responsive to β-decay from tritium (³H) and have sufficient stability in the aqueous media. DNA hybridization-based SPA was performed to determine whether the scintillation NPs could be utilized for SPA applications. A 30-mer oligonucleotide was immobilized on the polystyrene core-silica shell NPs to give approximately 7.6 x 10³ oligonucleotide molecules per NP and ³H-labeled complementary strand was annealed to the immobilized strand. At the saturation point, increases in scintillation signal due to oligonucleotide binding to the NPs were about 9 fold compared to the control experiments in which no specific binding occurred, demonstrating that the scintillation NPs can be utilized for SPA. Along with the improved physical properties including smaller size and better stability in the aqueous system, the developed scintillation NPs could be potentially useful as biosensors in cellular studies.
    • Fabrication of textured surface solar cells with the help of anisotropic etching

      Dixit, Suresh Gopal, 1946- (The University of Arizona., 1977)