background: taking visual acuity is an important part of an eye routine examination. this study was conducted to compare visual acuity measured using an iranian digital tumbling e chart with visual acuity measured using an italian digital tumbling e chart as a familiar foreign chart. materials and methods: this study was carried out on 200 participants (400 eyes; healthy n=40, glaucoma n=40, re...

PURPOSE To compare visual acuity (VA) assessed in healthy eyes and eyes with diabetic retinopathy (DR) using three different logMAR charts: the Sloan letter European-wide chart, the tumbling E chart, and the Landolt C chart. METHODS Measurements on one eye of 40 volunteers (aged 29 ± 4 years) without visual impairment and 31 DR patients (aged 70 ± 9 years) with mild/moderate visual impairment...

Method: Thirty-three clusters of 50 subjects ≥ 50 years old were randomly selected. Consenting subjects underwent enumeration to establish a demographic profile and thereafter a clinical examination. Visual acuity (VA) was measured with a Tumbling ‘E’ chart; participants having a VA < 6/18 were retested with a pinhole. If no improvement in VA occurred, subjects underwent clinical examination, i...

purpose: e is a commonly use letter for illiterates or those who could not read english to measure visual acuity. the e chart is the mainly used charts in iran. however, they do not have the standards. they are in different format, fixed for 6 meter test, with or without lighting, with unequal number of letters in each line and different contrasts. as a result, there is an essential need for a ...

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 ...

Chemotactic signaling in Escherichia coli involves transmission of both negative and positive signals. In order to examine mechanisms of signal processing, behavioral responses to dual inputs have been measured by using photoactivable "caged" compounds, computer video analysis, and chemoreceptor deletion mutants. Signaling from Tar and Tsr, two receptors that sense amino acids and pH, was studi...

AIM To introduce a new specialized visual acuity chart for amblyopic children aged 3-5 years old and its clinical applications. METHODS The new visual acuity chart and notations were designed based on Weber-Fechner law. The optotypes were red against a white background and were specially shaped four basic geometric symbols: circle, square, triangle, and cross. A regular geometric progression ...

AIM To introduce a new near-vision chart for children aged 3-5 years old and its clinical applications. METHODS The new near-vision chart which combined the Bailey-Lovie layout with a newly devised set of symmetry symbols was designed based on Weber-Fechner law. It consists of 15 rows of symmetry symbols, corresponding to a visual acuity range from 1.3 to 0.1 logMAR. The optotypes were red ag...

Chemotactic movement of Escherichia coli is one of the most thoroughly studied paradigms of simple behavior. Due to significant competitive advantage conferred by chemotaxis and to high evolution rates in bacteria, the chemotaxis system is expected to be strongly optimized. Bacteria follow gradients by performing temporal comparisons of chemoeffector concentrations along their runs, a strategy ...

We investigate the dynamics of a vesicle in a shear flow on the basis of the newly proposed advected field (AF) method [T. Biben and C. Misbah, Eur. Phys. J. E 67, 031908 (2003)]. We also solve the same problem with the boundary integral formulation for the sake of comparison. We find that the AF results presented previously overestimated the tumbling threshold due to the finite size of the mem...