In this photo illustration a package of Nicotine Gum, which is advertised as helping people stop smoking cigarettes, is seen on January 10, 2012 in Miami, Florida. A study published in the journal Tobacco Control on Monday, reported that the nicotine alternatives, like Nicotine Gum, have no lasting effect on people trying to quit their smoking habit. (Photo illustration by Joe Raedle/Getty Images)

South Korean special warfare command soldiers participate in winter military training exercise on January 11, 2012 in Pyeongchang-gun, South Korea. The South Korean troops train in temperatures below -20 degrees celsius to defend the country against any possible attacks from North Korea. (Photo by Chung Sung-Jun/Getty Images)

Snowdrops that are already in early bloom are seen at Rococo Gardens in Painswick on January 12, 2012 near Stroud, England. The unseasonably warm weather has seen wild flowers burst into bloom months ahead of schedule. However weather forecasters are warning of a return to colder temperatures later this week as a widespread frost is expected tonight. (Photo by Matt Cardy/Getty Images)

A train attendant helps a passenger to adjust her seat at the business class carriage on a CRH 380A bullet train Thursday, June 16, 2011. (Photo by Reuters/China Daily)

The entire cast perform during a production media call for Singin' In The Rain at Her Majesty's Theatre on May 12, 2016 in Melbourne, Australia. (Photo by Robert Cianflone/Getty Images)

A member of Alfama's group is seen before going to the Saint Anthony's Parade in Lisbon, Portugal June 12, 2016. (Photo by Rafael Marchante/Reuters)

Lucia Moreno, 28, participates in a Miss Tattoo contest during a tattoo convention in the Andalusian capital of Seville February 14, 2015. (Photo by Marcelo del Pozo/Reuters)

North Korean soldiers wave along the Yalu River, near the North Korean town of Sinuiju, opposite to the Chinese border city of Dandong October 7, 2014. (Photo by Jacky Chen/Reuters)