Relative assessment of cloth mask protection against ballistic droplets: A frugal approach.

During the COVID-19 pandemic, the relevance of evaluating the effectiveness of face masks-especially those made at home using a variety of materials-has become obvious. However, quantifying mask protection often requires sophisticated equipment. Using a frugal stain technique, here we quantify the "ballistic" droplets reaching a receptor from a jet-emitting source which mimics a coughing, sneezing or talking human-in real life, such droplets may host active SARS-CoV-2 virus able to replicate in the nasopharynx.

Biometry, Refractive Errors, and the Results of Cataract Surgery: A Large Sample Study.

The statistical characteristics of biometry and refractive error in a large sample of cataractous Cuban patients are presented, comparing between sexes and age groups. All patients were studied at the Cuban Institute of Ophthalmology "Ramón Pando Ferrer," La Habana. The sample consists of 28252 eyes of 25068 patients, subjected to cataract surgery during the time period between 2006 and 2019.

Using a multilayer perceptron in intraocular lens power calculation.

Purpose: To determine the capabilities of a multilayer perceptron (MLP) for calculating the power of an intraocular lens (IOL) to be implanted and in achieving a given postoperative stable refraction.

Setting: Cuban Institute of Ophthalmology, Havana, Cuba.

Design: Retrospective review.