to facilitate a comprehensive whole population visual acuity screening, a 1-meter vision screener “e” chart was prepared to be used in the person-by-person household visual acuity examination by non-expert health workers. the chart is designed to be used in measuring visual acuity from a distance of one meter. the scaling is in terms of-log mar (logarithm of minimum angle of resolution) with a ...

this study investigated the effect of using visual aids, semantic elaboration, and visual aids plus semantic elaboration on the iranian efl learners' vocabulary learning. to conduct the study, the researchers assigned 49 elementary learners to three homogeneous groups according to their proficiency level. then, a pre-test of paribakht and wesche's vocabulary knowledge scale was given ...

to evaluate the effects of the current situation and future development on source groundwater whether quantitative or qualitative point of view, simulation computer resources, a powerful tool in the optimal utilization of source is considered. year recent several model of math and computer simulation of hydraulic behavior of underground water resources focus is located. like making mathematical...

purpose: to assess the optical effect of the technis-z9000 iol decentration by lio-brennan mathematic-optical eye model. methods: the phantom with real eye parameters (lio-brennas) was used for iol technis-z9000 modeling with zemax code. modulation transfer function (mtf) and mtf contrast that represent the ratio of the image data to total object data in optical system were used for analysis. r...

purpose: to evaluate the visual outcomes of lasik in myopic eyes. methods: this interventional case series was performed on records of 345 eyes of 179 patients for correcting myopia with astigmatism < 3.00 diopter (d). all patients were operated by one surgeon (h.n.) with the nidek ec 5000 excimer laser. all patients had at least one year follow up. based on preoperative refraction, patients we...

objectives: human immunodeficiency virus type 1 is the causative agent of acquired immunodeficiency syndrome “aids” in human and demonstration of hiv-1 genome in samples is accepted as evidence of infection. transmission of infection during window period in blood transfusion settings is a world wide concern. also there is a need for a rapid, sensitive and accurate technique to detect hiv-1 infe...

purpose : to evaluate the biomechanical changes of cornea after intracorneal ring segment (icrs) implantation in keratoconic eyes methods : in this study, 1 or 2 icrs were inserted in 17 keratoconic eyes. best spectacle-corrected visual acuity (bscva), uncorrected visual acuity (ucva), refraction, and keratometry were evaluated preoperatively and 1 and 3 months after surgery. corneal hysteresis...

purpose: to compare long-term results of excimer laser sub-epithelial keratectomy (lasek) and laser in situ keratomileusis (lasik) for low to moderate myopia. methods: in a comparative case series, visual outcomes in 415 lasik-treated eyes (212 patients) and 359 lasek-treated eyes (194 patients) with myopia ranging from -1.5 to -5 diopters (d) and astigmatism up to -2.75 d using a flying spot e...