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Fort Worth (fort + worth)
Selected AbstractsImpacts of aircraft deicer and anti-icer runoff on receiving waters from Dallas/Fort worth International Airport, Texas, USAENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 11 2006Steven R. Corsi Abstract From October 2002 to April 2004, data were collected from Dallas/Fort Worth (DFW) International Airport (TX, USA) outfalls and receiving waters (Trigg Lake and Big Bear Creek) to document the magnitude and potential effects of aircraft deicer and anti-icer fluid (ADAF) runoff on water quality. Glycol concentrations at outfalls ranged from less than 18 to 23,800 mg/L, whereas concentrations in Big Bear Creek were less because of dilution, dispersion, and degradation, ranging from less than 18 to 230 mg/L. Annual loading results indicate that 10 and 35% of what was applied to aircraft was discharged to Big Bear Creek in 2003 and 2004, respectively. Glycol that entered Trigg Lake was diluted and degraded before reaching the lake outlet. Dissolved oxygen (DO) concentrations at airport outfalls sometimes were low (<2.0 mg/L) but typical of what was measured in an urban reference stream. In comparison, the DO concentration at Trigg Lake monitoring sites was consistently greater than 5.5 mg/L during the monitoring period, probably because of the installation of aerators in the lake by DFW personnel. The DO concentration in Big Bear Creek was very similar at sites upstream and downstream of airport influence (>5.0 mg/L). Results of toxicity tests indicate that effects on Ceriodaphnia dubia, Pimephales promelas, and Selanastrum capricornutum are influenced by type IV ADAF (anti-icer), not just type I ADAF (deicer) as is more commonly assumed. [source] Gas transmission for power generation in Dallas/Fort worthNATURAL GAS & ELECTRICITY (PREVIOUSLY : NATURAL GAS), Issue 4 2000Bill Geise [source] Waorani: The Contexts of Violence and WarAMERICAN ANTHROPOLOGIST, Issue 2 2000Klmberley Cook Waorani: The Contexts of Violence and War. Clayton Robarchek and Carole Robarchek. Fort Worth, TX: Harcouit Brace College Publishers, 1998. 202 pp. [source] Site characterization to support permeable reactive barrier designREMEDIATION, Issue 4 2005Lynn A. Morgan Careful design studies and selection of an effective technique for the installation of permeable reactive barriers (PRBs) are important contributors to the overall success of zero-valent iron PRBs. This article provides a case study summarizing the successful design and construction of a PRB installed at the former Carswell Air Force Base located in Fort Worth, Texas. Expedited site characterization using a cone penetrometer rig equipped with a mass spectrometer was employed to provide real-time characterization and lithologic data. These data proved to be invaluable for the design of the PRB and allowed for the development of an accurate preconstruction cost estimate. Field data gained from the expedited water quality and geologic characterization along with aquifer testing and a bench-scale treatability study provided a comprehensive basis for the design. The biopolymer slurry construction technique provided additional unanticipated benefits to the designed zero- valent iron treatment by promoting the development of anaerobic conditions favorable for microbial degradation of trichloroethene. Postconstruction monitoring data are discussed to illustrate the successful performance of the PRB. © 2005 Wiley Periodicals, Inc. [source] Fluid dynamics in three 25-gauge vitrectomy systems: principles for use in vitreoretinal surgeryACTA OPHTHALMOLOGICA, Issue 2 2008Octaviano Magalhães Jr Abstract. Purpose:, To compare infusion and extrusion fluid volumes with three 25-gauge vitrectomy systems. Methods:, The infusion and aspiration rates of 25-gauge systems from Alcon (Fort Worth, TX, USA), Bausch & Lomb (St Louis, MO, USA), and the Dutch Ophthalmic Research Centre (DORC, Zuidland, the Netherlands) were measured in vitro using balanced saline solution with different heights (40, 60, 80, 100, 120 cm) of infusion bottle, cutter velocities (800, 1100, 1500 cuts/ min) and aspiration powers (100, 200, 300, 400, 500 mmHg). Results:, The infusion flow velocities differed among the systems (p < 0.001 for all comparisons [p-values 0.0009,0.0001]). The aspiration rates of the Alcon and Bausch & Lomb systems were lower than that of the DORC system (p < 0.02 for all comparisons [p-values 0.018,0.002]). Conclusions:, Infusion and extrusion fluid rates differ among 25-gauge vitrectomy systems. These results may help to optimize ideal aspiration and infusion parameters among 25-gauge vitrectomy systems used to treat vitreoretinal diseases. [source] Aberration and contrast sensitivity comparison of aspherical and monofocal and multifocal intraocular lens eyesCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 4 2007Mingbing Zeng PhD MD Abstract Background:, Higher-order aberrations and contrast sensitivity were evaluated in patients who underwent phacoemulsification cataract extraction followed by implantation of aspherical, monofocal or multifocal intraocular lens (IOL) replacements. Methods:, In this comparative trial, 124 patients with an average age of 66.8 ± 5.2 years and their 124 eyes were randomly divided into three surgical implantation groups to receive one of three types of IOLs in replacement of cataract lenses. The patients of group 1 were given an aspherical IOL Z9001 (AMO, Santa Ana, CA, USA) replacement, and group 2 was implanted a monofocal IOL SA60AT (Alcon, Fort Worth, TX, USA) and group 3 the multifocal IOL SA40N (AMO). Post-surgical best-corrected visual acuity, corneal aberrations, total ocular aberrations, pupil diameters, capsulorhexsis sizes and contrast sensitivity were measured and compared. Results:, There was no statistical difference for mean best-corrected visual acuity, pupil diameter, curvilinear capsulorhexis size and corneal aberration among the three groups. For the spherical aberration, fourth-order higher-order aberration and total ocular higher-order aberration, the SA40N group was higher than the SA60AT group and the SA60AT group was higher than the Z9001 group, and the differences between the three groups were statistically significant for these measurements. Contrast sensitivity was higher for the Z9001 group than the SA60AT group and the SA60AT group was higher than the SA40N group, and the difference was statistically significant in all the spatial frequencies of 3, 6, 12 and 18. Conclusions:, Although the multifocal IOL can provide near vision, it can increase higher-order aberration and negatively influence contrast sensitivity. However, the aspherical IOL can reduce aberration and improve contrast sensitivity as compared with the monofocal IOL. [source] | |||||||||||||