French twins Thomas and Vincent (L) Seris take the tram in Bordeaux, November 12, 2014. Born with Xeroderma Pigmentosum (XP), the twins cannot be exposed to the sun and its ultraviolet (UV) light, which could provoke precocious cancers due to an autosomal recessive genetic disorder of DNA repair. Colloquially referred to as Children of the Night (Les Enfants de la Lune) the Seris twins are among 70 to 80 people in France who suffer from the genetic defect. The French association “Les Enfants de la Lune” reports that there are between five and ten thousand such cases in the world. Thomas and Vincent have been testing a new protective mask for the last year which is transparent and ventilated and developed by several hospitals in France. (Photo by Regis Duvignau/Reuters)

“By 1969, the fashion choices of tens of millions of young American men and women were as variegated and ever-evolving as the world around them. Cultural transformation was an irresistible force during the Sixties, and across America and around the globe civil rights, women’s and gay liberation, the sexual revolution and, of course, the explosive soundtrack of R&B, soul and rock and roll informed everything from politics to fashion”. – LIFE. Photo: Corona del Mar High School students Kim Robertson, Pat Auvenshine and Pam Pepin wear “hippie” fashions, 1969. (Photo by Arthur Schatz/Time & Life Pictures)

Construction continues on One World Trade Center (TALLEST BUILDING AT LOWER LEFT) as the memorial footprints of the twin towers are seen (BOTTOM C) on August 12, 2011 in New York City. Upon completion, One World Trade Center will be New York's tallest skyscraper, topping out at a symbolic 1,776 feet, with 3 million square feet of office space. More than 2,700 people were killed when al-Qaeda terrorists hijacked U.S. passenger jets and flew them into the twin towers of the World Trade Center on September 11, 2001. Nearly ten years after the crippling attacks on Lower Manhattan, business, tourism and new construction like One World Trade Center have rejuvenated the formerly devastated cityscape.(Photo by Mario Tama/Getty Images)

Mario Huettenhofer, chief of the German company 3D Fab, presents his own face as 3d print during the international fairs FabCon 3.D and Rapid.Tech in Erfurt, Germany, Thursday, May 15, 2014. 130 exhibitors from all over the world present the entire world of 3D printing. The trade fairs are accompanied by specialist programs featuring 80 scientists, practitioners and trend analysts from ten countries, who will explain the latest findings, trends and applications for additive processes in industry and for 3D printing in the private sector to newcomers, experts and consumers alike. (Photo by Jens Meyer/AP Photo)

Local villagers ride a local coal powered steam train on March 27, 2015 at a station in the town of Shixi , Sichuan Province, in Southern China. While China boasts the world's most extensive high-speed rail infrastructure with over 16,000 kilometers of track, the Shixi-Bagou railway is still a primary connection for local villagers between towns and is kept alive by tourist cars carrying passengers for ten times the price. The rail line came into service in the late 1950s and the train was initially used to transport coal from a now-shuttered mine before passenger carriages were added. (Photo by Kevin Frayer/Getty Images)

An Indian artist gives the finishing touches to a figure of the elephant-headed Hindu god Ganesha at a workshop ahead of the Ganesh Chaturthi festival in New Delhi on September 15, 2015. The idol is meant for the forthcoming festival Ganesha Chaturthi, a ten-day long event which is celebrated all over India. During the Ganpati festival, that is celebrated as the birthday of Lord Ganesha, idols of the Hindu deity are worshipped at hundreds of pandals or makeshift tents before they are immersed into water bodies. This year, the festival starts on 17 September 2015. (Photo by Sajjad Hussain/AFP Photo)