A rebel fighter fires toward Syrian government forces in the Bab al-Nasr district of Aleppo's Old City, earlier this month. The city has been a major battleground for the past six months.
Olivier Voisin/AFP/Getty Images
A woman wears a mask while walking in a park near the China Central Television Tower, background, on a hazy day in Beijing. The elderly, children and those suffering from respiratory and cardiovascular diseases are advised to stay indoors to reduce exposure to polluted air.
Alexander F. Yuan/AP
Hepatitis C patient Nancy Turner shows Kathleen Coleman, a nurse practitioner, where a forearm rash, a side effect of her treatment, has healed. Turner is one of many patients with hepatitis C experimenting with new drugs to beat back the virus.