Now showing items 14730-14749 of 14994

    • Visual Quality Metrics Resulting from Dynamic Corneal Tear Film Topography

      Greivenkamp, John; Solem, Cameron Cole; Greivenkamp, John; Schwiegerling, Jim; Liang, Rongguang (The University of Arizona., 2017)
      The visual quality effects from the dynamic behavior of the tear film have been determined through measurements acquired with a high resolution Twyman-Green interferometer. The base shape of the eye has been removed to isolate the aberrations induced by the tear film. The measured tear film was then combined with a typical human eye model to simulate visual performance. Fourier theory has been implemented to calculate the incoherent point spread function, the modulation transfer function, and the subjective quality factor for this system. Analysis software has been developed for ease of automation for large data sets, and outputs movies have been made that display these visual quality metrics alongside the tear film. Post processing software was written to identify and eliminate bad frames. As a whole, this software creates the potential for increased intuition about the connection between blinks, tear film dynamics and visual quality.
    • Visualization of the flow of fluid within a centrifugal pump

      Linka, James Edward, 1929- (The University of Arizona., 1965)
    • The visualizing of a corporate image for a new business

      Wade, Sydney Jean, 1937- (The University of Arizona., 1961)
    • Vitalizing high school physics

      Hyde, Jay, 1889- (The University of Arizona., 1939)
    • Vitamin A requirement of the hatchling sea turtle, Chelonia mydas

      Patterson, Jill Irene, 1950- (The University of Arizona., 1974)
    • Vitamin content of human milk

      King, Pin, 1947- (The University of Arizona., 1972)
    • Vitamin E turnover in cultured pulmonary alveolar macrophages

      Liebler, Daniel C.; Hoeger, Glenn Charles, 1962- (The University of Arizona., 1992)
      Vitamin E (α-TH), the primary lipid soluble antioxidant, can protect tissues from oxidative insult. Oxidant-producing pulmonary alveolar macrophages (PAM), may depend on α-TH to prevent oxidative damage. α-TH levels in cultured PAM declined rapidly during the first 12-18 hours in culture. Approximately 60% of the decrease was detected as unoxidized alpha-TH released to RPMI 1640 (containing 5% fetal bovine serum (FBS)) culture medium. α-TH was not detected in serum-free Ham's F12 medium. PAM appeared to reabsorb α-TH from the medium. PAM activation with phorbol myristate acetate (PMA) did not affect cellular α-TH depletion. However, the amount of α-TH detected in the medium of PMA treated cultures was only 50% of that detected in medium from untreated controls. Inhibition of superoxide production with iodoacetate had no effect on cellular depletion kinetics, however medium α-TH levels were still 50% of controls. Inhibition of nitric oxide, synthesis appeared to have no effect on α-TH status.
    • A vocabulary for the teaching of Spanish in elementary schools

      Clements, Harriet Eloise, 1897- (The University of Arizona., 1941)
    • Vocabulary instruction: Teacher perceptions and classroom observations

      Anders, Patricia L.; Bos, Candace S.; Miller, Susan Frances, 1962- (The University of Arizona., 1987)
      This study investigates the relationships between theory-based vocabulary research (Anderson and Freebody, 1981; Mezynski, 1983), teacher perceptions of the effectiveness and usability of twelve vocabulary strategies on a researcher-developed survey, and observations in content area classrooms during vocabulary instruction. Among the findings, the following are major: (1) Each hypothesis offers differing instructional implications for vocabulary instruction; (2) the responses on the survey indicate that strategies implied by the Knowledge Hypothesis are the most effective and strategies implied by the Instrumental Hypothesis are the most usable; (3) observations of five teachers indicate that observed behaviors, reported practices, and personal reports are inconsistent; and (4) triangulation of the three data sources reveals some consistency and some contradictions. Implications for future research, teacher education and practice are discussed.
    • The vocabulary of junior high school students

      Allhands, Tyler, 1905- (The University of Arizona., 1938)

      Gustafson, Donna Carol Winn. (The University of Arizona., 1982)

      Goldwasser, Sharon (The University of Arizona., 1987)
    • Vocal music for the seventh and eighth grade boys

      McGirr, Cencil Elmer, 1910- (The University of Arizona., 1947)
    • Vocal repertoire of the cactus wren (Campylorhynchus brunneicapillus)

      Wolford, Martha Jean, 1942- (The University of Arizona., 1969)
    • The vogue of Carlyle in England and America

      Meyer, Florence Jackson, 1899- (The University of Arizona., 1936)
    • Voice Characteristics of Individuals with Dementia Due to Suspected Alzheimer’s Disease: Three Case Studies

      Samlan, Robin A.; Abidov, Meira; Darling-White, Meghan; Grilli, Matthew; Marrone, Nicole (The University of Arizona., 2019)
      Previous studies have described communication changes to the speech and language of individuals with Alzheimer’s Disease (AD); however, other facets of communication, such as voice, have been left largely under-researched in this population. Perceived voice quality changes have not been reported as part of the disease process and reports of acoustic or aerodynamic correlates to vocal pitch, loudness, and quality are limited. The present study is a series of three case reports with the aim of gathering a preliminary dataset that can be used to identify key measures or differences that should be measured in a larger study. To this end, voice evaluation was completed in three people with suspected AD and results were compared to a control group of age- and gender- matched adults with typical cognition. Measures included a patient-reported quality of life scale, perceptual ratings of voice and speech, videostroboscopic ratings, cepstral peak prominence (CPP), low/high spectral ratio (L/H Ratio), mean fundamental frequency (fo), maximum phonational frequency range, mean airflow, and maximum inspiratory pressure (MIP). Co-variates included medical history and frailty screening. All three participants reported dysphonia. Endoscopic imaging for Participant 2 showed a bulky lesion of the right vocal fold. This lesion is likely the primary source of his dysphonia rather than AD. Imaging could not be obtained for participant 1 (P1) or 3 (P3). P1’s voice was rougher and breathier than the controls and P3’s voice was more severely impaired (overall) and breathier than controls. Acoustic results included normal CPP and low L/H Ratio for P1 and P3. Aerodynamic results included lower than expected MIP for all three participants and elevated mean airflow only for P3. These results provide preliminary evidence that disordered voice quality can exist in people with AD. It is clear that there are many possible causes of voice disorder that will need to be considered when designing the larger study. These include medical co-morbidities, age, frailty, cognitive and general motor status, hearing loss, and frequent interaction with people with hearing losses. While L/H Ratio was more sensitive to perceived voice quality differences than CPP for these participants, the measure should be retained in future studies. A more natural speech sample is also recommended to eliminate potential effects of reading on speech production and to assess prosodic changes in typical conversation.