LD

LD may refer to:

In science and mathematics:

The logarithm of base 2, , from the Latin logarithmus dualis

In technology:

Eric Clapton

Eric Patrick Clapton, CBE (born 30 March 1945), is an English rock and blues guitarist, singer and songwriter. He is the only three-time inductee to the Rock and Roll Hall of Fame: once as a solo artist and separately as a member of the Yardbirds and Cream. Clapton has been referred to as one of the most important and influential guitarists of all time. Clapton ranked second in Rolling Stone magazine's list of the "100 Greatest Guitarists of All Time" and fourth in Gibson's "Top 50 Guitarists of All Time". He was also named number five in Time magazine's list of "The 10 Best Electric Guitar Players" in 2009.

In the mid-1960s, Clapton left the Yardbirds to play blues with John Mayall & the Bluesbreakers. Immediately after leaving Mayall, Clapton formed the power trio Cream with drummer Ginger Baker and bassist Jack Bruce, in which Clapton played sustained blues improvisations and "arty, blues-based psychedelic pop". Furthermore, he formed blues rock band Blind Faith with Baker, Steve Winwood, and Ric Grech. For most of the 1970s, Clapton's output bore the influence of the mellow style of JJ Cale and the reggae of Bob Marley. His version of Marley's "I Shot the Sheriff" helped reggae reach a mass market. Two of his most popular recordings were "Layla", recorded with Derek and the Dominos; and Robert Johnson's "Crossroads", recorded with Cream. Following the death of his son Conor in 1991, Clapton's grief was expressed in the song "Tears in Heaven", which featured in his Unplugged album.

Cocaine

Cocaine, also known as benzoylmethylecgonine or coke, is a strong stimulant mostly used as a recreational drug. It is commonly snorted, inhaled, or injected into the veins. Mental effects may include loss of contact with reality, an intense feeling of happiness, or agitation. Physical symptoms may include a fast heart rate, sweating, and large pupils. High doses can result in very high blood pressure or body temperature. Effects begin within seconds to minutes of use and last between five and ninety minutes. Cocaine has a small number of accepted medical uses such as numbing and decreasing bleeding during nasal surgery.

Cocaine is addictive due to its effect on the reward pathway in the brain. After a short period of use, there is a high risk that dependence will occur. Its use also increases the risk of stroke, myocardial infarction, lung problems in those who smoke it, blood infections, and sudden cardiac death. Cocaine sold on the street is commonly mixed with local anesthetics, cornstarch, quinine, or sugar which can result in additional toxicity. Following repeated doses a person may have decreased ability to feel pleasure and be very physically tired.

Medicine show

Medicine shows were traveling truck, horse, and wagon teams which peddled "miracle cure" medications and other products between various entertainment acts. They developed from European mountebank shows and were common in the 19th century United States, especially in the Old West era (though they continued up to World War II). They are most commonly associated with "miracle elixirs" (sometimes referred to as snake oil), which, it was claimed, had the ability to cure any disease, smooth wrinkles, remove stains, prolong life or cure any number of common ailments. Most shows had their own patent medicine (these medicines were for the most part unpatented but took the name to sound official). Entertainment often included a freak show, a flea circus, musical acts, magic tricks, jokes, or storytelling. Each show was run by a man posing as a doctor who drew the crowd with a monologue. The entertainers, such as acrobats, musclemen, magicians, dancers, ventriloquists, exotic performers, and trick shots, kept the crowd around until the salesman sold his medicine.

Old Crow Medicine Show

Old Crow Medicine Show is an Americana string band based in Nashville, Tennessee. Its music has been called old-time, folk, and alt-country. Along with original songs, the band performs many pre-World War II blues and folk songs. It has recorded since 1998. Bluegrass musician Doc Watson discovered it while its members were busking outside a pharmacy in Boone, North Carolina in 2000. With an old-time string sound fueled by punk rock energy, it has influenced acts like Mumford & Sons and contributed to a revival of banjo-picking string bands playing Americana music—leading to variations on it.

The band released five studio albums—O.C.M.S. (2004), Big Iron World (2006), Tennessee Pusher (2008), Carry Me Back (2012), and Remedy (2014). Their song "Wagon Wheel", written by frontman Ketch Secor through a co-authoring arrangement with Bob Dylan, was certified platinum by the Recording Industry Association of America in April 2013 and has been covered by a number of acts, including Darius Rucker, who made the song a top 40 hit.