Information on the ozone concentration in the surface air and troposphere in the first half of 2020 is presented. The data were acquired at 13 stations in different Russian regions;vertical distributions were obtained...
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Information on the ozone concentration in the surface air and troposphere in the first half of 2020 is presented. The data were acquired at 13 stations in different Russian regions;vertical distributions were obtained with the use of an aircraft laboratory. The excess over the Russian Federation hygienic standards is assessed;the daily average ozone concentration is found to be regularly higher the maximum permissible concentrations at most stations. At some stations, there are features the seasonal variations in the ozone concentration in the period under study different from previous years.
Purpose: To assess the efficacy of hyperopic laser in situ keratomileusis (LASIK) in creating orthophoria without optical correction in adult patients with refractive accommodative esotropia (RAE). Setting: Instituto ...
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Purpose: To assess the efficacy of hyperopic laser in situ keratomileusis (LASIK) in creating orthophoria without optical correction in adult patients with refractive accommodative esotropia (RAE). Setting: Instituto Oftalmologico de Sabadell, Sabadell, Barcelona, Spain. Methods: This prospective single-center clinical trial studied 9 eyes (18 patients) with RAE having hyperopic LASIK. The mean follow-up was 20 months (range 12 to 24 months). The mean preoperative refraction was +5.01 diopters (D) and the mean deviation angle without optical correction, 36 prism diopters. The intervention was hyperopic LASIK using the Automated Corneal Shaper(R) microkeratome (Bausch & Lomb) and the Apollo broad-beam excimer laser using a 5.5 mm optical zone and an 8.0 mm transition zone;astigmatism was treated by steepening the flattest meridian. Results: All patients achieved orthophoria or the preoperative microtropia without optical correction immediately after surgery. This was maintained throughout the follow-up. Fifty-six percent of all cases were within +/-0.5 D of emmetropia, and 89% were within +/-1.0 D. The uncorrected visual acuity improved significantly (P < .005), especially at near, and the mean best corrected visual acuity (BCVA) was maintained, although 4 eyes (22%) lost 1 line of BCVA. There were no significant complications. Conclusions: In adult patients with RAE, treatment of the refractive error using hyperopic LASIK was safe and effective and corrected the esodeviation. Further studies in younger patients will help determine the age at which this intervention may be indicated.
Designers in general have used diagrams and sketches to help in the process of creation. This is particularly so for system designers whose output is a set of programs. It would seem reasonable that the conversion of ...
Designers in general have used diagrams and sketches to help in the process of creation. This is particularly so for system designers whose output is a set of programs. It would seem reasonable that the conversion of diagrams directly into a program would be desirable and yet the work of Green and Petre [3-4, 13] and Citrin [2] has placed doubt on the viability of graphical programming notations. Some of this work is reviewed in this paper. The use of secondary notation and the match-mismatch hypothesis is reconsidered in the light of functional programming. It is proposed that much of the criticism of graphical notation is due to the imperative (or process orientated) nature of programming. Many of the limitations observed in using graphical notation are lifted when functional programming is used. Eight engineering dimensions and four engineering relationships (coherences) are proposed to describe programming environments (including notation). The source of 'knotty structures' is identified as embedded 'if then else' or 'if' statements. On analysing both imperative and functional programs it was found that imperative programs used an order of magnitude larger number of 'if's than functional programs. The key to the success of a functional language as a general representation as well as its coherence with a graphical notation comes from its unique extensibility. Support for these arguments is drawn from examples of a schematic programming language used for industrial scale projects. It is concluded that the marriage between a functional language and its graphical representation overcomes most of the original criticisms of graphical programming. It is demonstrated that this combination makes a viable and expressive tool for industrial-sized applications. (C) 2001 Academic Press.
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