Rohingya refugee sisters Nur Kaida (R) and Ruhana hug each other at their shelter at the Palongkhali refugee camp near Cox's Bazar, Bangladesh December 21, 2017. (Photo by Marko Djurica/Reuters)

Vehicles pass through the heavy fog and air pollution that cover Skopje valley in the early morning, in Skopje, The Former Yugoslav Republic of Macedonia, 14 December 2017. According to media reports, Skopje is considered one of the most polluted cities in the world. (Photo by Georgi Licovski/EPA/EFE)

Girls sits on a bench during summer at the Central Park in New York, United States, 2011. (Photo by An Rong Xu)

Bicycles of various bike-sharing services are seen at an urban village in smog during a polluted day in Shanghai, 2017. Rapid expansion of shared bicycle companies across China has led to massive piles of abandoned bikes as supply outstrips demand. (Photo by Aly Song/Reuters)

In this picture taken late on June 13, 2017, physiotherapist Masayuki Ozaki takes a bath with his silicone s*x doll Mayu at a love hotel in Yachimata, Chiba prefecture. Around 2,000 of the life- like dolls – which cost around 6,000 USD and come with adjustable fingers, removable head and life- like genitals – are sold each year in Japan, according to industry insiders. (Photo by Behrouz Mehri/AFP Photo)

A model displays a creation by French designer Isagus Toche, during eco-clothing fashion show from recycled materials in Kiev, Ukraine, on 23 June 2017. (Photo by Stepan Franko/EPA/EFE)

Snow covered pine tree reaches for the sky. Shot in Sweden on a crisp winter day. (Photo by Anna Rebecka Lindberg/The Guardian)

A boy listens to a prayer before he and other relatives visit the grave of their loved ones, all minors, who were killed a year ago during the government's war on drugs campaign, at the Tala Cemetery in Caloocan, east of Manila on December 28, 2017, as the world commemorates Holy Innocents' Day. Catholics celebrate the biblical passage when King Herodes the great ordered to kill all newborn babies to kill Jesus Christ. (Photo by Noel Celis/AFP Photo)