Trachea annular ligaments of trachea. The epiglottis closes the opening to the larynx during swallowing. The trachea develops in the second month of development. It is lined with an epithelium that has goblet cells which produce protective mucins (see "Respiratory epithelium"). An inflammatory condition, also involving the larynx and bronchi, called croup can result in a barking cough. A tracheotomy is often performed for ventilation in surgical operations where needed. Intubation is also carried out for the same reason by the inserting of a tube into the trachea. From 2008, operations have experimentally transplanted a windpipe grown by stem cells, and
Facebook real-name policy controversy the acronym is employed, Facebook automatically changes to lower-case all letters except the first. (Use of periods, e.g. D.L.G., will result in a message telling users that "Profile names can't have too many periods.") Therefore, someone commonly known in real life by a name such as Mary De Leon Guerrero Mafnas would have to resort to using what on Facebook would end up being "Mary Dlg Mafnas". The message is not accompanied by an option to challenge/appeal the restriction or to send Facebook documentation that the format is how one normally formats their name in real life. In January 2015,