Now showing items 14233-14252 of 14895

    • The ultrastructure of retinal development in the chicken

      Miller, Mahlon Frederick, 1940- (The University of Arizona., 1965)
    • Ultraviolet and ultrasound disinfection of a recycle irrigation water

      Hardcastle, Clavin Hunter,1959-; Sierka, Raymond A. (The University of Arizona., 1987)
      Disinfection of an irrigation recycle water is evaluated by an investigation divided into three phases. Phase I experiments investigates disinfection by ultraviolet light alone; Phase II examines ultrasound disinfection; and Phase III investigates combined effects of ultrasound and ultraviolet light. Phase III also evaluates unit process sequencing in order to optimize disinfection performance. Ultraviolet light produced an average microorganism inactivation of 85.4% following one minute of UV irradiation. The response became asymptotic at this point. Cell viability, measured by ATP concentration, was not reduced below 10% until 15 minutes of UV treatment. Ultrasonic treatment resulted in microorganism survivals ranging fram 66.4% (60 W/1 and 30 minutes of treatment) to 25.1% (350 W/1 and 30 minutes of treatment). Combined treatment processes produced comparable results to UV only disinfection schemes. Overall, a satisfactory level of disinfection was not attained using UV light or ultrasound. The lack of disinfection response was attributable to the presence of interfering water constituents.
    • The Umma Within The Umma. How Al-Qaeda In The Arabian Peninsula’s Inspire Magazine Defines Moral Boundaries

      Nassar, Maha T.; Tarantini, Lara; Hudson, Leila O.; Noorani, Yaseen (The University of Arizona., 2018)
      In analyzing the content of al-Qaeda in the Arabian Peninsula’s Inspire magazine, I argue that the concept of Imagined Moral Umma should be utilized. I define the Imagined Moral Umma as an imagined community whose boundaries are determined by the moral standards of its members. By means of utilizing this framework, this thesis shows how AQAP creates a finite umma within a (virtually) infinite umma. Furthermore, this thesis shows firstly that the boundaries of this Imagined Moral Umma are flexible: inclusion and exclusion from this community depend upon historical contingencies. Secondly, the concept of takfīr (excommunication from the Muslim community) becomes irrelevant in Inspire magazine’s justification of violence against Muslims. Thirdly, this thesis highlights the ideological shift within Inspire magazine from a chiefly anti-Western propaganda to an anti-imperialist rhetoric.
    • Una Propuesta de Analisis para las Oraciones Copulativas en Espanol

      Riqueros Morante, Jose Francisco Francisco; Olarrea, Antxon (The University of Arizona., 2007)
      La distinción entre copulativas ecuativas (p.e. Ana es la única mujer) y predicativas (p.e. Ana es una mujer) se basa en criterios sintácticos. En las ecuativas, la concordancia de género entre el sujeto y el complemento no es obligatoria (p.e. Pepe era la chica de azul sentada allá) y éste se reemplaza por un pronombre nominativo (p.e. Pepe es el chico sentado allá/Pepe es él). En las predicativas, la concordancia de género y número entre el sujeto y el complemento, aparentemente, es obligatoria (p.e. Ana es linda/*-o,*-as,*-os) y éste se reemplaza por el indeclinable lo (p.e. Ana lo/*ella/*la/*le es). Propongo que estos datos sirven de base para postular que ecuativas y predicativas no comparten una estructura sintáctica común en el español. Perelstvaig (2000), a partir de datos del ruso y del italiano, explica que la diferencia entre predicativas y ecuativas se debe a que las primeras incluyen una Cláusula Reducida (CR) cuyo núcleo es una categoría funcional predicativa (Ø) (p.e. cópula [FDet-(Ø)-FN]) y las segundas no tienen tal núcleo (p.e. cópula [FDet₁-FDet₂]). En la misma línea, Haegeman (1994) propone que las predicativas incluyen una categoría funcional –concordancia de género y número (Conc)– en su CR (p.e. cópula [FDet-(Conc)-FN]) y las ecuativas no. Los datos del español no sostienen ambas propuestas ya que no es posible argumentar que en las CRs de las predicativas hay una categoría funcional: no hay necesidad de concordancia de género (e.g. el león(i.masc) es [t(i), una fiera(fem)]) ni de número (e.g. los cuchillos(i.masc) son [ti, una amenaza(fem)]). Por otro lado, la literatura no reconoce que las ecuativas presentan una semejanza con las predicativas: no hay necesidad de concordancia de género (e.g. Ellas(fem) son los invitados(masc) disfrazados de esa mesa). Sánchez y Camacho (1993) plantearon una diferencia estructural entre ecuativas y predicativas; pero su explicación es incompleta porque no incluyen las restricciones de Caso que se imponen a los nominales. Mi propuesta sí considera tales restricciones y se basa en: a) la exigencia teórica de que los nominales deben estar marcados con Caso y b) la evidencia interlingüística proveniente de lenguas como el sinhala, el islandés, el árabe, el latín y el ruso, que marcan con Caso los nominales de las copulativas; a diferencia de éstas, la marcación de Caso en español se hace evidente en la distribución pronominal. Propongo que el patrón casual ecuativo es NOM-NOM (p.e. Ana es la monja/ Ella es la monja/Ana es ella) y que el patrón predicativo es NOM-Predicativo(PRE). PRE es un nuevo rasgo que el indeclinable lo evidencia (p.e. Ana es una monja/Ella es una monja/Ana lo es). Crucialmente, los datos de la copulativas rusas en pretérito (Perelstvaig,2000) presentan ambos patrones; pero en vez de PRE el Caso es Instrumental (INS) (p.e. (NOM)[Oleg] cópula (NOM)[direktor] en las ecuativas, y (NOM)[Oleg] cópula (INS)[direktorom] en las predicativas). En español, el rasgo NOM y el rasgo PRE de los nominales postcopulares se licencian mediante la operación Agree (Chomsky 2000,2001). El rasgo NOM se licencia gracias a T° y el rasgo PRE se legitima gracias a Asp°, núcleo de la FAsp propuesta por Zagona (2002), que es parte del verbo aspectual ser.
    • Unawareness of deficits in Huntington's disease

      Kaszniak, Alfred W.; McGlynn, Susan Mary, 1960- (The University of Arizona., 1989)
      Several new techniques were developed to assess quantitatively the degree to which patients with Huntington's disease (HD) are aware of their deficits, to evaluate the relation between cognitive impairment and unawareness of deficits, and to determine whether patients exhibit differential awareness of their motor disturbance and cognitive deficits. Results of a questionnaire measure indicated that HD patients rated their own difficulties with motor and cognitive activities of daily life significantly lower than relatives rated patients' problems, and this discrepancy was related to patients' level of cognitive impairment. In contrast, patients were reasonably accurate when predicting their performance on specific motor and cognitive tasks when compared to both their actual performance and relatives' predictions. Several interpretations of these findings are discussed, and the role of frontal lobe dysfunction in the awareness problems characterizing dementia is considered.
    • Uncertainty estimation of hydrological models using bayesian inference methods

      Sorooshian, Soroosh; Thiemann, Michael; Sorooshian, Soroosh (The University of Arizona., 1999)
      Intensive investigations of hydrologic model calibration during the last two decades have resulted in a reasonably good understanding of the issues involved in the process of estimating the numerous parameters employed by these codes. Nevertheless, these classical "batch" calibration approaches require substantial amounts of data to be stable, and the subsequent model forecasts do not usually represent the various imbedded uncertainties. Especially in the light of thousands of uncalibrated catchments in need of model simulations for streamflow predictions, a parameter estimation approach is required that is able to simultaneously perform model calibration and prediction without neglecting the substantial uncertainties in the computed forecasts. This thesis introduces the Bayesian Recursive Estimation scheme (BaRE), a method derived from Bayesian probability computation and adapted for the use in "on-line" hydrologic model calibration. The results of preliminary case studies are presented to illustrate the practicality of this simple and efficient approach.
    • Uncertainty in cardiac transplant recipients prior to and after cardiac catheterization

      Verran, Joyce A.; Nicholson, Suzanne Maria (The University of Arizona., 1987)
      The purpose of this study was to describe the presence of uncertainty experienced by heart transplant recipients at one and two year diagnostic follow-up evaluations. Twelve one year and eleven two year transplant recipients completed the Mishel Uncertainty in Illness Scale (MUIS), prior to and after cardiac catheterization. There was a decrease in uncertainty levels from pre to post-catheterization, for both one and two year recipients, however, findings were not significant. Recipients prior experience with catheterization and the interaction effects of the complete evaluation process or future health status may have affected the subject's uncertainty response. Two year transplant recipients demonstrated significantly higher uncertaintly levels, before and after cardiac catheterization, when compared to one year recipients. These findings lend initial and tentative support to the proposal that uncertainty increases with time post-transplant. The yearly follow-up evaluation may represent an episodic focusing for the transplant recipient on health status.

      Deans, Charles Baldwin. (The University of Arizona., 1982)
    • Uncertainty, spirituality, religiosity, and psychosocial outcomes among culturally diverse, younger women with breast cancer

      Braden, Carrie Jo; Barroero, Linda Sue; Braden, Carrie Jo (The University of Arizona., 1999)
      The purpose of this descriptive-exploratory, secondary analysis of data from the Self-Help Intervention Project (SHIP) was to explore the ability of the factors, uncertainty, spirituality, and religiosity, among young Hispanic and Anglo women with breast cancer, to differentiate between those who demonstrated psychosocial maladjustment and those who did not. The sample consisted of low income, younger (M=41. 75) Anglo (n=93) and Hispanic (n=96) women recently diagnosed with breast cancer. Discriminant analysis with stepwise selection procedures was used to identify the predictor variables of psychosocial adjustment as measured by the social and psychological self-report domains of the PAIS. This study supported a positive relationship between uncertainty levels and psychosocial adjustment, demonstrating high prediction accuracy of nonmaladjustment (social=92.3%, psychological=85.2%) but with less accuracy for maladjustment (29.3%, 43.1 %). Spirituality and religiosity were entered with uncertainty yielding limited additional explanatory power for the group as a whole or the Hispanic women. However, three items entered for social adjustment among the Anglo women, improving prediction of maladjustment to 58.30% and for non-maladjustment, 92.60%. The addition of spirituality and religiosity among the Anglo women for psychological adjustment only improved prediction for the non-maladjusted group. Implications and limitations are discussed.
    • Unconfined aquifer recharge from water table configuration modeling

      Brown, Steven Robin,1961-; Evans, Daniel D.; Maddock, Thomas, III; Yeh, T.C. Jim (The University of Arizona., 1986)
      The potential of estimating steady recharge to deep unconfined aquifers by comparing observed water levels to the water levels produced by a series of simulated cases was examined. Finite-element simulations were performed on an idealized region to examine the sensitivity of the water table position to anisotropy, recharge, grid density, horizontal layering, and region geometry. The position of the water table was found to be particularly sensitive to region geometry, medium heterogeneity and anisotropy. A graphical method based on comparison of water levels at three observation points to simulated water levels produced a good estimate of dimensionless recharge and the anisotropy ratio. Determination of the absolute value of recharge requires accurate determination of region geometry and hydraulic conductivity so that computer simulations are representative. An analytical solution to the Boussinesq equation was found to give a poor estimate of water table position and hence recharge for this case.
    • Undergraduate art students: Influences affecting the career decision to major in art

      Greer, W. D.; Kreamer, Lisa Marie (The University of Arizona., 1997)
      This thesis surveys 171 undergraduate art students at the University of Arizona to evaluate the effect their high school art teachers had on their career decision to enter a college art program. The parental influence is addressed. Student responses are viewed by gender, classification and major. Findings indicate the teachers influence less than 50% of their students and that parents have a greater influence in the decision process. There are definite gender differences, males talked with their parents more than females but females expressed more support from parents once in an art program. Students in commercially viable studio programs, graphic design and photography, report greater parental support.
    • Understanding and employment of marketing functions by small retailers

      Nelson, William Bischoff, 1940- (The University of Arizona., 1963)
    • Understanding Reform: A Study of the Standards Movement in Mathematics Education

      Civil, Marta; Hathaway Turner, Arias Storm; Civil, Marta; Ylimaki, Rose; Adiredja, Aditya (The University of Arizona., 2016)
      This thesis explores the historical and ongoing efforts to reform mathematics education in the United States. The goal of this study is to understand the Common Core State Standards for Mathematics (CCSSM), or Common Core, in the context of the greater standards movement first initiated by the National Council of Teachers of Mathematics (NCTM). A common theme throughout this study is the complexity of reform and the tensions that exist when implementing change. To understand issues facing reform efforts, I contextualize the ongoing standards movement by summarizing historical factors that contributed to the development and reception of standards in education. This history began with societal changes that led to standardization of different social institutions and continues with an ongoing standards movement in education. To carry out this study, I relied on literary sources as well as on the insights of three individuals that had unique experiences with the standards movement. With this context, I discuss the Common Core movement and greater challenges facing reform in mathematics education. The main finding I present in this study is that controversy surrounding national standards is likely to persist as long as there is a tension between standardization and local control of education.
    • Understanding the Current Educational Climate in California Arts Magnet Schools

      Garber, Elizabeth; Colbert, Cortney Alan; Garber, Elizabeth; Beudert; Arenas (The University of Arizona., 2007)
      The Magnet Program for California public schools was established with the purpose of allowing students to have some choice in how they are educated. Each magnet school has a specific curriculum emphasis. This study focuses on those classified as Art Magnet Schools. With the advent of such legislation as the No Child Left Behind Act, schools have placed an increased emphasis on Math, Science, and Language Arts. This emphasis has been pushed along in part, by an increase in high-stakes testing that is taking place in all public schools. This has caused a shaky ground for Arts Magnet Schools in California to stand on. Some schools are finding that their emphasis in Arts is now in jeopardy. This study shows that although the perception of the majority of teachers is that things are worse currently than in the past, they are optimistic as to what will occur in the future.
    • Understanding the Impact of Students' Psychological Dispositions and Behavior on Student Exam Performance in an Undergraduate Business Statistics Course

      Kersting, Nicole B.; Marinan, Brent Joseph; Kersting, Nicole B.; Watkins, Joseph C.; Barnes, Katherine Y. (The University of Arizona., 2016)
      Research on K-12 and college students has shown that both cognitive and non-cognitive factors affect students' academic achievement and success. This study investigates the impact of several non-cognitive factors (i.e., anxiety, beliefs, habits, motivation, context, and grit) on undergraduate students’ exam performance in a public research university. Participants were 646 undergraduate students taking a statistics course designed for business students. To obtain measures of students’ psychological dispositions and behaviors, students completed a survey that was developed for this study three times during the course of the semester, each time before students took one of the three course’s exams. Results from the three surveys indicated that although the impact of different non-cognitive factors on exam performance decreased over the course of the semester, anxiety, beliefs and intrinsic motivation statistically significantly predicted student exam scores and the cumulative exam score. In addition, results from latent class analysis of the first wave of survey responses allowed for the determination of several diagnostic classifications of students whose academic performance, as measured by their cumulative exam scores, may benefit from early intervention.

      Troch, Peter; Broxton, Patrick; Troch, Peter; Brooks, Paul; McIntosh, Jennifer (The University of Arizona., 2008)
      In surface hydrology, much attention is paid to the effects of changing water fluxes, however there is less of a focus on the effects of changing energy fluxes. These energy fluxes are an important driver of many hydrological processes such as evapotranspiration and snow sublimation/ablation. The hypothesis that varying energy fluxes are important to the hydrological features of a catchment is tested by an experiment that involves calculating mean transit times for a number of catchments that drain different aspects of a large dome located in the Valles Caldera, New Mexico, called Redondo Peak. These catchments have different orientations and therefore receive different amounts of solar radiation. There is a general correlation between mean transit times, as determined by lumped-parameter convolution, and aspect, suggesting that in the Valles Caldera, transit times might be affected by a variety of features that are influenced by exposure to solar radiation, such as slope steepness, vegetation patterns, and soil depth. To put these transit times into context, I also used a distributed physically-based model to simulate a number of factors simultaneously to determine how hydrological features are influenced by aspect. This modeling excercise has illuminated the aspect-dependence of hydrological features such as the timing and intensity of snowmelt and soil moisture patterns, and it has quantified differences in energy and water fluxes on different aspects. These factors affect both water storage and water fluxes, and are therefore tied to transit times.
    • Understanding the Mechanism of Cancer Therapeutic SAH5-EJ1 in Targeting Breast Cancer Metastasis

      Schroeder, Joyce A.; Soyfer, Eli Michael; Paek, Andrew L.; McEvoy, Justina D. (The University of Arizona., 2020)
      While many breast cancer subtypes overexpress members of the ERBB family of receptor tyrosine kinases (including the Epidermal Growth Factor Receptor/EGFR, HER2, ERBB3 and ERBB4), only HER2 has been effectively targeted. Evidence indicates that established therapeutics against EGFR targeting either the extracellular domain or the kinase domain fail due to unique biological activities of the receptor in breast cancer. In light of this, a stapled peptide mimicking the EGFR juxtamembrane domain (SAH5-EJ1) was developed and found to induce complete tumor regression in a model of inflammatory breast cancer (SUM149/NODSCID). SAH5-EJ1 was found to induce both necrosis and apoptosis through calcium and ROSdependent mechanisms, but the mechanism by which this was achieved was unknown. In the current study, we have evaluated EGFR-dependent calcium signaling as a means to promote cell death. We have discovered that SAH5-EJ1-induced cell death is dependent upon expression of both EGFR and the TRPV1 (transient receptor potential cation channel subfamily V member 1) calcium channel located on the plasma membrane. Mechanistically, SAH5-EJ1induces the activation of TRPV1, resulting in a dramatic influx of extracellular calcium. This is followed by a sharp rise in cellular reactive oxygen species (ROS) into the cell and induction of cell death. These data demonstrate a reliance of EGFR on calcium signaling in breast cancer survival, one which can be effectively targeted in breast cancer.
    • Understanding the Role of Climate and Socioeconomic Factors in Driving Irrigated Agriculture Dynamics in the Lower Colorado River Basin

      Smith, William K.; Norton, Cynthia Libantino; van Leeuwen, Willem J.D.; Wallace, Cynthia (The University of Arizona., 2019)
      Understanding the dynamics of agriculture in relation to climate and socioeconomic variables such as market value is essential in assessing water use within a semi-arid basin. This study aims to improve understanding of the spatial and temporal variability of agriculture fallowing and crop productivity using satellite Normalized Difference Vegetation Index (NDVI), meteorological observations and socioeconomic data across two regions in Arizona: the Lower Colorado River Planning (LCRP) region in LCRP County and the Active Management Areas (PMAMA) in Maricopa County and Pinal County. A key difference between these regions is there access to water for irrigation: LCRP has 1st priority (senior) irrigation water access rights, whereas PMAMA has 3rd priority (junior) irrigation water access rights. Using Google Earth Engine, I produced annual extent of fallow and active croplands at high spatial resolution (30-m) from 2001-2017 by applying the Fallow-land Algorithm based on Neighborhood and Temporal Anomalies (FANTA) driven by 8-day normalized difference vegetation index (NDVI) for each region of interest. I then evaluated how factors including weather and market value have influenced management decisions for seasonal fallowing using statistical modeling. Results show that LCRP (with senior water rights) varied very little in agricultural extent from year to year (87 - 90% active) compared to PMAMA (77 - 84% active) potentially due to regional differences in growing season and water rights. Agricultural extent and productivity in both regions was found to be sensitive to biophysical factors, with LCRP most sensitive to aridity (R2=0.486) and PMAMA most sensitive to precipitation (R2=0.358). Finally, we found market value significantly increased regional climate sensitivity, such that agricultural productivity was highest when both biophysical constraints were low and market values were high. This research effort provides a framework and demonstrates the importance of separately analyzing patterns of agricultural extent and productivity, which I found to interact in complex ways with both biophysical (e.g., drought) and socioeconomic (e.g., market value) factors to explain year to year variability in total regional agricultural production.