Tens of thousands of HIV positive prostitutes in the slums of Lagos to ensure a rapid spread of the epidemic. “If you arrive by car, you can smell the HIV virus outside”, joked my driver as we are on track to Badia a criminal slums of Lagos. Badia is a corruption of “Bad Area”. Nigerians have a lack of everything, except black humor. The poor West African country Nigeria, with a population of 140 million people, after India and South Africa the highest number of people with HIV / AIDS. (Photo by Ton Koene/Exclusivepix Media)

People carry drinks at 80s Bar in Damascus, Syria, March 11, 2016. In Damascus's Old City, just a mile from the battered frontline between government and rebel-held territory, young Syrians smoke, drink beer or soft drinks, and talk about anything but the war. The revival of activity in this once-vibrant quarter is part of efforts to project an air of normality in the Syrian capital, even as the five-year-old war that has killed more than 250,000 people and created 5 million refugees continues to rage nearby. (Photo by Omar Sanadiki/Reuters)

A Shinto priest prays to the dedicated dolls during the Festival of Repayment of Kindness at Dairoku-tensakaki Shrine in Tokyo, Saturday, May 16, 2015. Traditionally, it is believed that the dolls can give good health and happiness to children by absorbing sickness and ill fate. The dolls are then sacrificed during the festival after they have protected their young owners. (Photo by Eugene Hoshiko/AP Photo)

Masooma Alizada (L) and Frozan Rasooli (R), members of Afghanistan's Women's National Cycling Team prepare a bicycle before training on the outskirts of Kabul February 20, 2015. Afghanistan's Women's National Cycling Team has been breaking new ground for women's sports and pushing the boundaries of what is – and is not – acceptable for young women in the conservative Muslim country. (Photo by Mohammad Ismail/Reuters)

Sea lions wait on the deck of the boat before being released in front of Palomino island, in Callao, Peru September 12, 2015. Four young sea lions returned to the wild after being rescued by marine biologists and treated for various illnesses. The sea lions are survivors of various illnesses which they contracted off the coast of Peru caused by the elevated temperatures in the water because of the El Nino phenomenon, according to Carlos Yaipen, Director of Animal Science and Well-being Organization (ORCA). (Photo by Mariana Bazo/Reuters)

Macro or Micro? Scientists’ pictures baffle our sense of scale. It began when Stephen Young, a geography professor at Salem State University in Massachusetts, tricked his biologist colleague Paul Kelly into thinking a satellite image was one of his electron microscope scans. Can you guess whether they are close-up or very far away? (Photo by Paul Kelly)

Gaikuo-Captain is a young Chinese student of chemical engineering, and a talented illustrator. His passion for the comic was demonstrated by a series of works that combine drawings with photographs, so that he himself is "immersed" in a fantasy to interact with characters from comic books and manga. His pieces are successful in social networks, particularly in Weibo, Chinese social network where Gaikuo publishes. You can see all his work on his zcool profile.

A family of baby brown bears appear to be dancing to Ring a Ring o' Roses as their mother relaxes behind a tree nearby. At just a few months old, two young males and one female gather in a circle, clutch each others' hands and begin to dance to the popular nursery rhyme. It's almost like a scene from a school playground as the bears joyfully play together, tapping their feet and moving around in a circle. (Photo by Valtteri Mulkahainen/Solent News & Photo Agency)