objective: classic cell culture and karyotyping is routinely used for prenatal detection of different chromosomal abnormalities. molecular cytogenetic techniques have also recently been developed and used for this purpose. quantitative florescence pcr using short tandem repeat (str) markers has more potential for high throughput diagnosis. marker heterozygosity in short tandem repeats (str) is ...

An achromatic element eliminating only longitudinal chromatic aberration (LCA) while maintaining transverse chromatic aberration (TCA) is established for the eye model, which involves the angle formed by the visual and optical axis. To investigate the impacts of higher-order aberrations on vision, the actual data of higher-order aberrations of human eyes with three typical levels are introduced...

We investigated the impact in spatial visual performance of the combined presence of different amounts of spherical aberration and intraocular scattering in the eye. In a group of subjects, contrast sensitivity at 6 cycles per degree was measured when viewing through holographic diffusers to produce different levels of scattering and with their spherical aberration simultaneously controlled usi...

In this study, the wave-front aberrations of medium and high myopia with different CCT after SMILE were studied by finite element method. Then, various trend clinical significance was obtained. When same, diopters different. increased, variations However, regardless degree myopia, defocus primary spherical aberration most obvious. The larger CCT, smaller absolute values aberration.

PURPOSE To analyze the post operative results of targeting zero spherical aberration by selecting the best-fit aspheric intraocular lens (IOL), based on preoperative corneal spherical aberration of patients with phacoemulsification surgery. SETTING AlHokama Eye Specialist Center, Riyadh, Saudi Arabia. PERIOD From the 1st of October 2012 until the 10th of April 2013. METHODS Fifty-three ey...

We present theoretical estimates of the mean coefficients of spherical and chromatic aberration for low energy photoemission electron microscopy (PEEM). Using simple analytic models, we find that the aberration coefficients depend primarily on the difference between the photon energy and the photoemission threshold, as expected. However, the shape of the photoelectron spectral distribution impa...

Scanning confocal electron microscopy (SCEM) is a new imaging mode in electron microscopy. Spherical aberration corrected electron microscope instruments fitted with two aberration correctors can be used in this mode which provides improved depth resolution and selectivity compared to optical sectioning in a conventional scanning transmission geometry. In this article, we consider a confocal op...