Now showing items 14538-14557 of 14895

    • Variability in Comprehension: A Look at the Proficiency Level and Working Memory Functions Among Nonnative Readers of Arabic

      Shiri, Sonia; Assaoui, Hicham; Farwaneh, Samira; Bever, Thomas G. (The University of Arizona., 2016)
      This paper investigates the influence of readers' linguistic proficiency level and working memory functions on the reading behaviors and processes of readers of Arabic as a foreign language (henceforth RAFL). Two aspects of reading comprehension, speed and accuracy, are examined in light of readers' word decoding efficiency, recall performances, response times, scores, and readers' responses to two quantitative tests: a questionnaire and an interview. Twenty-four subjects participated in this study and were divided into two subgroups based on their proficiency level. The proficiency of these subjects was determined based on their academic level and their overall GPA in Arabic. All subjects completed a series of reading passages, in two separate sessions, followed by comprehension questions. Reading and answer time on the reading passages and questions were timed and scored. Data was also collected retrospectively using a questionnaire and an interview. The results suggest that reading comprehension and the ability to select and implement specific reading processes are impacted by the proficiency level of subjects as well as their word decoding skills. A strong correlation between comprehension outcomes and working memory functions was also found. That is, working memory capacity was found to be influential on the reading behaviors of readers especially at the sentence level with better performances reported for readers with larger and more elaborate vocabulary repertoire. Based on these results, some implications and conclusions are discussed for both Arabic reading research and foreign language classroom.
    • Variability in nondormant Medicago sativa L. ecotypes from India and their relationship to African and Arabian alfalfas

      Smith, Steven E.; Warburton, Marilyn Louise, 1968- (The University of Arizona., 1991)
      Understanding patterns of genetic diversity in crop species may enhance the efficiency of germplasm conservation and utilization. Nondormant alfalfa (Medicago sativa L.) is an important forage crop in southwest Arizona, and originates from low elevations of the Middle East and India. This study examined 60 accessions of nondormant alfalfa from India, north Africa and Arabia in a field trial in Tucson, AZ during 1989-91. Nondormant Indian and African alfalfas have previously been considered independent germplasm sources. Principal components of 6 morphological and 15 agronomic traits were used to classify accessions using average linkage cluster analysis. Low elevation Indian accessions did not differ phenotypically from most African and Arabian alfalfas. This indicates that Indian alfalfas are not an independent source of germplasm in need of conservation as such, but western Arabian alfalfas may be.
    • Variability of pesticides in human blood serum

      Apple, Gail Illsley, 1941- (The University of Arizona., 1968)
    • A variable moduli probabilistic constitutive model for soils

      Kulatilake, Pinnaduwa H. S. W.; Reed, Philip Edward, 1959- (The University of Arizona., 1988)
      Measurement of stress - strain relationships in soil systems usually incorporate varying degrees of uncertainty. These uncertainties arise from laboratory testing mechanisms, sampling disturbances, errors performed by operators or technicians performing the tests, etc. Currently, deformation analyses have been modeled using several deterministic techniques. However, because of the uncertainties involved, there is a need to adapt these numerical methods into probabilistic models. This thesis develops a probabilistic constitutive model based on a variable moduli deterministic technique. First-order, second-moment stochastic methods are used to estimate a mean stress - strain curve and its ±1 standard deviation from raw data obtained on nearly identical, remolded sand samples. Probabilistic estimations for Bulk and Shear moduli are determined from the estimated mean curves and are used to develop a probabilistic constitutive model. Through the use of a probabilistic constitutive matrix, a stochastic equation is produced which can relate strains to any stress state imposed on a particular soil. This is verified through an example.
    • The variable popularity of the works of F. Scott Fitzgerald

      Kinney, John Cummings, 1934- (The University of Arizona., 1957)

      Myslicki, Stefan Leopold, 1953- (The University of Arizona., 1987)
      This study uses Monte Carlo simulation to examine the performance of a variable frequency sampling cumulative sum control chart scheme for controlling the mean of a normal process. The study compares the performance of the method with that of a standard fixed interval sampling cumulative sum control chart scheme. The results indicate that the variable frequency sampling cumulative sum control chart scheme is superior to the standard cumulative sum control chart scheme in detecting a small to moderate shift in the process mean.
    • A variable thickness plate analogy

      Chorman, George Gardham, 1938- (The University of Arizona., 1964)
    • Variables associated with alcoholics' long term treatment success

      Kahn, Marvin; Clemens, Camille Willette, 1963- (The University of Arizona., 1987)
      This study investigated demographic and personality variables, that counselors used in the selection of alcoholics for long term treatment and compared the completion rate for this group against completion rates reported in past studies, in order to determine if certain personality variables are associated with completion. The MMPI, Survey of Drinking Patterns and Effects, and a demographic questionnaire was administered to 355 lower class and "skid row" inpatient alcoholics from a North Tucson alcoholism treatment center. Results showed that counselors selection judgements approximated the characteristics of alcoholics who had completed long term treatment programs in past studies. Completion rates for this group studied were found to be moderately high compared to past studies. It was concluded that certain biographical and psychological variables can be used as selection criteria for determining alcoholics long term treatment completion. Implications for these findings are discussed.
    • Variables influencing community cardiopulmonary resuscitation course participation

      Sherman, Jacqueline B.; Bartholomeaux, Frances Marie, 1955- (The University of Arizona., 1990)
      This study investigated the variables influencing community cardiopulmonary resuscitation (CPR) course participation. Forty-seven adults, male and female, participated in a descriptive study. Three questionnaires were given to participants of two community CPR courses: the Cues to Action questionnaire, the Health Belief Model in Cardiopulmonary Resuscitation questionnaire, and the Health Self-Determinism Index. The results indicated positive relationships between an individual's perceived susceptibility of others and perceived benefits in CPR course participation and utilization, and between cues to action and intrinsic motivations, specifically health judgments. The results also demonstrated an expected negative correlation between perceived benefits and perceived barriers; i.e., the benefits outweighed the barriers to CPR course participation and utilization. The results are all marketable concepts which can be utilized in promoting CPR course utilization and participation.
    • Variables influencing community cardiopulmonary resuscitation course participation

      Sennott-Miller, Lee; Mulkerin, Patrick Owen; Badger, Terry; Black, Jane (The University of Arizona., 1998)
      This study investigated variables influencing community cardiopulmonary resuscitation (CPR) course participation. Fifty-one adults, 18 male and 33 female, participated in a descriptive study. A treatment groupof25 attended a free CPR class. A comparison group of26 did not attend the class. All subjects completed four questionnaires testing demographic characteristics, beliefs, experience, and intrinsic motivation to perform CPR. The only significant difference between treatment and comparison groups was that females were more likely to attend than males ( p ~ .05 ). Intrinsic motivation measured by the Health Self Determinism Index ( HSDI) failed to separate treatment and comparison groups. Motivation may be less important in participation in CPR training than more personal variables, or the HSDI may not be adequate to test feelings about learning CPR. In future research, increased sample size from more diverse populations may yield more useful information.
    • Variables that contribute to the success of watershed organizations: analysis of past efforts in developing nations with an application in the Mexican portion of the upper San Pedro River basin

      Moreno Ramírez, Denise.; de Steiguer, J. E.; Browning-Aiken, Anne; Wilder, Margaret (The University of Arizona., 2005)
      At an international level, the management of water resources has become a highly contested topic. It is important to take into account this current need for efficient water resource use and management to protect future surface and groundwater supplies. Also, it is particularly important to consider that public participation should be implicit within such issues, especially when it is the public that is impacted by decisions. As in the case of emerging water resource management schemes such as IWRM, public participation is manifested as watershed organizations. Within developing nations such as Mexico, both watershed organizations and IWRM are important when consider water resource management. With this in mind, this thesis proposes to examine successful developing nation watershed organization variables and then apply what is learned to a specific case study. It presents a systematic and comprehensive review of the empirical literature from 1988 to 2004 and extracts case study examples from developing nations with the intent to create a model of a "successful" watershed organization. Statistical processes were used to analyze the developing nation watershed organization variables to develop a model. Also, the developing nation watershed organization model produced will be compared to the Mexican portion of the Upper San Pedro River Basin case study, ARASA. To complete this portion of the analysis, ethnographic methods were employed to produce an organizational profile and timeline.
    • Variables that Influence the Endangered Pima Pineapple Cactus (Coryphantha scheeri var. robustispina) Mortality after Transplanting

      Fehmi, Jeffrey S.; Berthelette, Gerald M.; Fehmi, Jeffrey S.; McClaran, Mitchel P.; Crawford, Julie (The University of Arizona., 2017)
      Coryphantha scheeri var. robustispina (Schott) L. Benson, the Pima pineapple cactus, herein referred to as C. scheeri, was declared an endangered species in 1993 and only occurs in a limited range in Arizona, USA and northern Sonora, Mexico between 2,300'-4,500' asl. Development within the range of C. scheeri threatens individuals, but transplanting to conserve them while allowing for development has been considered to be ineffective for conservation due to low post-transplant survival rates in past studies. The construction of a natural gas pipeline provided the opportunity to conduct a transplant experiment on 82 individual C. scheeri transplanted in July and August 2014. The plants were randomized into one of four transplant methods: bare-root with supplemental water, bare-root without supplemental water, soil-and-plant moved with supplemental water, and soil-and-plant moved without supplemental water. Higher than average precipitation occurred during the 2014 monsoon season including after transplanting. A subset of the transplanted C. scheeri (n=17) were transplanted back onto the pipeline after pipeline construction was completed. Survival rates were monitored through December 2016 and compared to undisturbed C. scheeri near the pipeline ROW and those on other sites. For the plants transplanted once, no significant effect of moving the plants with soil compared to no soil (X2 = 2.9, p = 0.09), no significant effect of adding water at the time of transplant compared to not adding water (X2 = 1.2, p = 0.26), and no significant interaction among treatments (X2 = 0.06, p = 0.81) was observed. For plants transplanted twice, a significant effect of moving the plants with the soil compared to no soil (X2 = 5.0, p = 0.02) was found, while due to the random selection of plants to be transplanted twice there was too little data to adequately test other comparisons. There was no significant difference in mortality between the transplanted once (27% mortality) and the transplanted twice (31% mortality) treatments (p = 0.78), but there was a significant difference between transplanted and non-transplanted plants (2% mortality in non-transplanted plants; p < 0.05). Soil series did not appear correlated with mortality. Plants in good condition (scored 4 or 5 on scale of 0-5) at the time of transplanting had low mortality rates (16%) while plants scored 3 or lower had high mortality rates (60%) but deaths did not occur immediately after transplanting: 5 died after 8 or 9 months, 4 after 13-16 months, and 9 after 23 or 24 months. The majority of the deaths occurred after numerous months of declining in condition but six plants died suddenly. Good condition plants were more likely to flower than those in poor condition. Transplanting appears to conserve some of the C. scheeri population which would have otherwise been lost to development.
    • Variación en una Situación de Contacto Lingüístico entre el Español y el Catalán

      Simonet, Miquel; Ramírez Martínez, Marta; Carvalho, Ana M.; Colina, Sonia (The University of Arizona., 2012)
      Este estudio analiza la percepción y producción del contraste catalán entre la fricativa alveopalatal sonora y la lateral palatal por parte de bilingües de Mallorca, España: un grupo de hispano-dominantes (HD) y otro de catalano-dominantes (CD). El estudio de producción consistió en la repetición de frases en catalán. El estudio de percepción consistió en una tarea de discriminación de uno de tres sonidos que no formaba parte de la misma categoría sonora. Hubo diferencias perceptuales significativas entre los dos grupos. Esto apoya que la adquisición de una segunda lengua aun durante la infancia conlleva consecuencias durante la edad adulta de un bilingüe. Los resultados de producción concordaron con los de percepción: los CD mantuvieron el contraste, y los HD no lo mantuvieron. Se discuten las implicaciones de estos hallazgos para nuestra comprensión del bilingüismo, la adquisición de los sonidos de una L2 y el cambio lingüístico motivado por el contacto.
    • Variation in a restricted population of the Valley pocket gopher (Thomomys bottae)

      Dingman, Ross Evan, 1928- (The University of Arizona., 1966)
    • Variation in Immune Response Among Native and Invading Genotypes of Yellow Starthistle (Centaurea solstitialis)

      Dlugosch, Katrina M.; Kaczowka, Angela M.; Dlugosch, Katrina M.; Gallery, Rachel E.; Chesson, Peter (The University of Arizona., 2017)
      Invasive plants may leave enemies behind when they colonize a new habitat, allowing selection to favor increased investment in growth and/or reproduction over defensive traits. Previous studies have identified reduced diversity of potential bacterial pathogens and evolutionary increases in growth and reproduction in invading populations of yellow starthistle (Centaurea solstitialis). This study leverages a recently developed high-throughput assay of immune function to test for evidence of a trade-off between increased growth and defense against bacterial pathogens in yellow starthistle's invasion of California (USA). Seven bacterial strains were cultured from infected leaf tissue in the native range. Healthy leaf tissue from five native European collections and six invading collections were exposed to these native bacterial strains. A standardized assay of peroxidase activity was used measure the oxidative burst immune response to pathogen recognition by the leaf. Immune responses were compared to plant growth within and between ranges to assess evidence for a trade-off. Plant genotypes from the native range demonstrated a higher immune response to bacterial strains than did invading genotypes, consistent with a trade-off with plant growth across regions. The same trade-off was also apparent across genotypes from the native range, but not across genotypes from the invaded range. Our results provide evidence that increased growth in a highly invasive plant species may come at a cost to immune function, consistent with the hypothesis that escape from enemies can provide opportunities for shifts in resource allocation that favor the proliferation of non-native species.
    • Variation in wax content, fatty acids and fatty alcohols of jojoba seed (Simmondsia chinensis)

      Salazar Zazueta, Alfredo Javier, 1951- (The University of Arizona., 1977)
    • Variation of adaptation of selected commercial hybrid grain sorghums (Sorghum bicolor (L.) Moench) and their two successive segregating generations to variable environments

      Dobbs, Carol Johnson, 1963- (The University of Arizona., 1990)
      Crop performance depends on genotype, the environment in which the crop is grown, and interaction between genotype and environment. A measure of these effects is important in determining adaptation and in recommending crop genotypes to growers. In instances where hybrid seed has been introduced into developing countries, which often traditionally save seed for the next planting, determining the adaptation of genotypes and making accurate recomendations may be difficult. This experiment evaluated 15 commercial hybrid grain sorghums (Sorghum bicolor (L.) Moench), along with their segregating F₂ and F₃ generations, for adaptation to variable moisture environments. Grain yield per entry in all tests was the main phenotypic character used to measure adaptation in environments differing in mean moisture stress. Grain yield was also the main characteristic used to observe changes through generations F₁ to F₃.There was an expected decrease in yield with decreased irrigation, and with advanced generations. A close association was observed between mean 3-year grain yield of the selected hybrids and their F₂ and F₃ progenies when grown in the same environment.
    • The variation of specific gravity of gelatin with pH and with concentration

      Ruddock, Ruth, 1919- (The University of Arizona., 1941)