Tears

Tearing (/ˈtiərɪŋ/), lacrimation, or lachrymation, (from Latin lacrima, meaning "tear") is the secretion of tears, which often serves to clean and lubricate the eyes in response to an irritation of the eyes. Tears formed through crying are associated with strong internal emotions, such as sorrow, elation, emotion, love, awe or pleasure. Laughing or yawning may also lead to the production of tears.

Physiology

In humans, the tear film coating the eye, known as the precorneal film, has three distinct layers, from the most outer surface:

Having a thin tear film may prevent one's ability to wear contact lenses, as the amount of oxygen needed is higher than normal, and contact lenses stop oxygen from entering the eye. Eyes with thin tear film will dry out while wearing contact lenses. Special eye drops are available for contact lens wearers. Certain types of contact lenses are designed to let more oxygen through to the eye.

Drainage of tear film

The lacrimal glands secrete lacrimal fluid, which flows through the main excretory ducts into the space between the eyeball and lids. When the eyes blink, the lacrimal fluid is spread across the surface of the eye. Lacrimal fluid gathers in the lacrimal lake, and is drawn into the puncta by capillary action, then flows through the lacrimal canaliculi at the inner corner of the eyelids entering the lacrimal sac, then on to the nasolacrimal duct, and finally into the nasal cavity. An excess of tears, as with strong emotion, can thus cause the nose to run.

Don

Don or DON and variants may refer to:

People

Chemistry

Geography

Bullet for My Valentine

Bullet for My Valentine are a Welsh heavy metal band from Bridgend, formed in 1998. The band is composed of Matthew Tuck (lead vocals, rhythm guitar), Michael Paget (lead guitar, backing vocals), Michael Thomas (drums) and Jamie Mathias (bass guitar). Former members include Nick Crandle and Jason James; both were on bass. They were formed under the name Jeff Killed John and started their music career by covering songs by Metallica and Nirvana. Jeff Killed John recorded six songs which were not released; two of these tracks were reworked later in their career as Bullet for My Valentine. Financial difficulties dictated the name change, which was followed by a change in music direction. In 2002, the band secured a five-album deal with Sony BMG. The band has stated that their music is influenced by classic metal acts such as Metallica, Iron Maiden, and Slayer. The band is part of the Cardiff music scene.

Bullet for My Valentine's debut album, The Poison, was released on 3 October 2005 in the United Kingdom and on 14 February 2006 in the United States to coincide with Valentine's Day, in a nod to the band's name. The album entered the US Billboard 200 at number 128. It was certified Gold by the Recording Industry Association of America. The band made appearances at the Download Festival and Kerrang! XXV, and undertook a US tour with Rob Zombie. Bullet for My Valentine's second studio album, Scream Aim Fire, was released on 29 January 2008 and debuted at number four on the Billboard 200. The band's third album, Fever, was released on 26 April 2010 and debuted at number three on the Billboard 200. On February 8, 2013, the band released their fourth studio album, Temper Temper, which peaked at number 13 on the Billboard 200. The band has sold over one million albums in the United States and over 5,000,000 albums worldwide and are the most-successful act in the Kerrang! Awards category of "Best British Band" with three wins.