purpose: controversy has recently risen about the presence of compensatory ocular countertorsion (coct) after head tilt. this study was performed to define the functional range of this phenomenon. methods: cycloplegic autorefraction was performed on 80 eyes with regular astigmatism 2d. objective autorefraction was performed in normal position, right and left head tilt positions of 5º, 10º, 15º,...

paratus. In activity 2, students can use the equipment used by hobby winemakers – a vinometer – to measure the alcohol content of the must and wine. 3. A well balanced wine needs a certain amount of fruit acid; the total acid content is a very important measure, because it directly affects the flavour. In activity 3, the acid content is determined by pH titration. Four further activitiesw2 can ...

Quantitative chemical analysis has served as a useful tool for understanding cellular metabolisms in biology. Among many physical properties used in chemical analysis, refractive index in particular has provided molecular concentration that is an important indicator for biological activities. In this report, we present a method of extracting full-field refractive index maps of live cells in the...

A ray-theoretic account of the passage of light through a radially inhomogeneous transparent sphere has been used to establish the existence of multiple primary rainbows for some refractive index profiles. The existence of such additional bows is a consequence of a sufficiently attractive potential in the interior of the drop, i.e. the refractive index gradient should be sufficiently negative t...

In this work, the splitting of resonance lines in a Fabry-Perot resonator formed by section standard curved single-mode fiber with metal-coated ends is investigated numerically and experimentally. It shown that similar to Autler-Townes results from strong coupling between fundamental mode core whispering gallery cladding fiber. The influence all basic parameters on its reflection transmission s...