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  Best Management Practices for Sea Isle 2000 Surface Conditions as a Putting Green Turf Under Desert Conditions

  Kopec, David M.; Gilbert, Jeff J.; Walworth, James; Pessarakli, Mohammed; Kerr, D.; Spence, J.; Kopec, David M. (College of Agriculture and Life Sciences, University of Arizona (Tucson, AZ), 2004-02)

  Sea Isle 2000, the recently developed Seashore paspalum cultivar intended for use on golf greens, was subjected to various surface cultivation practices of grooming, vertical mowing, and topdressing frequency, in order to investigate the (1) effects of these cultural practices on turfgrass quality (2) effects on ball roll distance (BRD), so as to devise best management practices (BMP) for cultural management recommendations for this grass in a hot/dry climate. The trial was conducted for the two summer seasons of 2002 (year1), and 2003 (year 2). Turfgrass quality in year 1 was significantly affected by imposed management treatments on all four evaluation dates, in which the groom vs. non-groom contrast was highly significant. Nongroomed treatments produced better quality than turf groomed 5-6x weekly. In year two, the cultural management treatment effect was not significant, and treatment means ranged from 5.5 to 7.8. The nongroomed/ topdressed and verticut at 14-day treatment had mean quality scores of 7.0 or greater on three of four evaluations in year two. This treatment had the least number of cultural management contact events. The most aggressive treatment in terms of the number of contact events (groom/topdressed and vertically mowed at 7 days) never reached a mean quality score of 7.0, but had acceptable turf otherwise (6.8, 6.5, 5.8 and 6.5 in year two). The treatments that did not receive any vertical mowing (groom/topdressed and verticut at 7 days and groomed/topdressed and verticut at 14 days) always produced mean turf quality scores of 6.0 or above. Over the two year test, the nongroomed treatments which were both verticut and topdressed at 7 or 14 day intervals had 12 of 16 possible quality mean scores of 7.0 or more. The turfs which were groomed and topdressed only at 7 or 14 day intervals (never verticut) had mean quality scores of 7.0 or more on 6 of 16 possible rating scores. Turfs that were groomed/topdressed and verticut at either 7 or 14`day intervals had mean quality scores of 7.0 or greater on 4 of 16 possible evaluation scores. For Ball roll distance (BRD) in year one, the treatment F ratio was significant on five of the ten BRD measurement events, with significance occurring on double mowed turfs on three events, and twice when plots received supplemental rolling. Rolling with an 875 lb Brouer roller numerically increased BRD values on all treatments (over double mowing alone) on 5 July, 16 August, and 26 August, decreased BRD values on 19 July, and had no effect for BRD on 26 July. The greatest BRD values which occurred during year one, was a test mean of 103 inches (double mow only) and 98" for rolled turfs. In year two, the treatment F ratio for treatment effects was not statistically significant on any evaluation date. This was true when BRD was taken after turfs were double mowed, and also followed by rolling. Rolling had minimal benefit, and was inconsistent in BRD effect. BRD was almost 20% greater in year two than a in year one. When BRD was recorded only after double mowing, turfs that were not groomed ranked numerically higher than groomed turfs for BRD response on all data sampling dates in year one. In general, turfs which received the most frequent number of cultural management practices (regular grooming, topdressing and vertical mowing ) tended to have the lowest ranking BRD values, except towards the seasons end (16 and 26 August). Although the main "treatment" effect in the ANOVA was significant on 3 of 5 collection dates (for double mowed BRD values), these trends show that in general, regular grooming decreased BRD values more so than for non-groomed surfaces. In year two, BRD values were essentially identical in mean performance, ranging only a few inches in BRD when measured after the standard double mowing. The greatest difference in BRD among treatments occurred on 27 June, as a BRD of 99.8" occurred for turfs that were non-groomed/topdressed and vertically mowed every 7 days versus non-groomed/topdressed and vertically mowed every 14 days (105"). Again note that there were no significant treatment effects for BRD in year two. When BRD was measured after mowing, followed by additional rolling , the rolling effect tended to increase BRD values across all treatments in year one, except in July, which normally had the most humid weather. Rolling did increase BRD values by 10% in early July (July 5), but also decreased, or had no effect on BRD in the middle or late July (16 and 26 July), and then increased BRD values slightly in August (16, 26 August) of year one. Although the largest increase in BRD values from rolling occurred in early July (almost 9 inches) of year one, the effect was not significant between surface treatments. Rolling was significant when imparted across surface management treatments in August of year 1, as at least one of the two non-groomed turfs tended to have the largest BRD values after rolling. In year two, supplemental rolling imparted very little gain in BRD, except in late September. Substantial increases or decreases in BRD did not occur from rolling relative to treatments in year two, as sometimes occurred in year one. BRD averages across all treatments (with the addition of rolling) were from 96.4" - 109.8" in year two. For both years, rolling) was inconsistent with respect to BRD. Rolling on the day of BRD assessment only sometimes increased, decreased, or had no effect on BRD. Rolling as a regular cultural management treatment should be evaluated. BMPS for Quality and BRD Performance together: In year one, the "groom" treatment which was verticut and topdressed every 7 days always ranked the slowest for BRD responses. While this specific treatment always ranked lowest in BRD, it did not have the lowest overall turf quality scores. Groomed turfs which were verticut and topdressed every 14 days ranked the lowest for quality scores on three of four evaluation dates. Therefore in year one, treatments which produced (in general terms) the greatest BRD values and ranked the highest in overall quality were turfs which received no-grooming, and topdressed either every 14 or 7 days. The treatment which produced the lowest ranking BRD values and lowest ranking quality scores in year one, was the treatment of grooming, verticutting and topdressing every 14 days. In year two, BRD was not related to any surface cultivation treatment. Although not statistically significant, nongroomed plots topdressed either at 7 or 14 day intervals, ranked first for BRD in late season (3 September, 30 September). BRD values were in general, 10-20% greater across all treatments in 2003 than in 2002. Although BRD and quality were not significant in year two, certain trends resulted over the two year test period in that plots that were not groomed had mean treatment quality scores of 7.0 or more on 12 of 16 possible (joint treatment) evaluations. These treatments also had high BRD values. Also, treatments devoid of vertical mowing (groomed/topdressed only at either 7 or 14 day intervals) produced mean quality scores of 7.0 or more on 6 of 16 possible (joint treatment) events over the two year period. BRD values for these treatments were always within 1-2 inches of the test mean BRD values as well. Treatments which received the most frequent contact events (regular grooming/topdress/verticut at either 7 or 14 day intervals over two years, had mean quality scores of 7.0 or greater on only 16 possible events. Over the course of the study, in general, turfs which were non-groomed / verticut and topdressed @ either 7 or 14 day intervals produced the higher ranking quality turfs, along with higher ranking BRD performance. Long term BRD values would most likely include a mixture of topdressing and verticutting either at 7 or 14 days internals, with grooming practiced on an as needed basis, especially during the first two thirds of the summer season.
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  Effect of Retaining Ring Slot Designs, Conditioning Discs and Conditioning Schemes on the Slurry Bow Wave Width during Chemical Mechanical Planarization

  Bengochea, Leticia Vazquez; Sampurno, Yasa; Stuffle, Calliandra; Sudargho, Fransisca; Han, Ruochen; Philipossian, Ara; Univ Arizona, Dept Chem & Environm Engn (ELECTROCHEMICAL SOC INC, 2018)

  This study investigates the effect of various retaining ring slot designs, conditioning schemes and conditioning disc types on the width of the slurry bow wave formed at the leading edge of the retaining ring during polishing. A method using high-speed videography is employed for visualizing and quantifying slurry bow wave width. In contrast to many limitations associated with previous techniques, this new method allows the use of a concentrically grooved pad with its natural white color commonly used in industrial applications. In general, results show that polishing with a retaining ring having rounded-angle slots, and a full-face conditioner, generates wider slurry bow waves. In contrast, using a retaining ring with sharp-angle slots, in combination with a conditioner having CVD-coated protruding vanes results in narrower bow waves. Compared to ex-situ conditioning, in-situ conditioning causes narrower bow waves due to its inherent role in transporting the slurry through periodic sweeping. Using Fast Fourier Transformation (FFT), bow wave width fluctuations are converted from time domain to frequency domain, showing a consistent spectral fingerprint. Major peaks are observed at frequencies of 1, 2, 4, 8 to 9, and 12 to 14 Hz for all experiments and they are attributed to the carrier, platen and conditioning disc rotation and oscillation, as well as to the presence of slots on the retaining ring. (C) 2018 The Electrochemical Society.
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  Figural properties are prioritized for search under conditions of uncertainty: Setting boundary conditions on claims that figures automatically attract attention

  Peterson, Mary A.; Mojica, Andrew J.; Salvagio, Elizabeth; Kimchi, Ruth; Psychology Department, University of Arizona; Cognitive Science Program, University of Arizona (SPRINGER, 2016-10-28)

  Nelson and Palmer (2007) concluded that figures/figural properties automatically attract attention, after they found that participants were faster to detect/discriminate targets appearing where a portion of a familiar object was suggested in an otherwise ambiguous display. We investigated whether these effects are truly automatic and whether they generalize to another figural property-convexity. We found that Nelson and Palmer's results do generalize to convexity, but only when participants are uncertain regarding when and where the target will appear. Dependence on uncertainty regarding target location/timing was also observed for familiarity. Thus, although we could replicate and extend Nelson and Palmer's results, our experiments showed that figures do not automatically draw attention. In addition, our research went beyond Nelson and Palmer's, in that we were able to separate figural properties from perceived figures. Because figural properties are regularities that predict where objects lie in the visual field, our results join other evidence that regularities in the environment can attract attention. More generally, our results are consistent with Bayesian theories in which priors are given more weight under conditions of uncertainty.