Chinese and Pakistani air force personnel sit in a Pakistani fighter after a joint drill in China, Sept 14, 2017

Professor Chang is a Co-Director of the Tumor Virology Laboratory at the University of Pittsburgh Cancer InstituteIn the last 15 years, 43 Citation Laureates have gone on to receive Nobel honors, so the prize has been seen as an indicator of the Nobel prizes, introduced in memory of Swedish chemist Alfred Nobel (1833-1896)

Each year, analysts at Clarivate Analytics mine millions of citations in the Web of Science, an online subscription-based scientific citation indexing service, to identify top-tier researchers in physiology or medicine, physics, chemistry and economicsKaposi's sarcoma-associated herpesvirus is the infectious cause of this neoplasmHere, we present some of the most striking images around the world this past week

Children cool off themselves at a wading pool in Toronto, Canada, on Sept 24, 2017The vice-premier said China is willing to work with the US to prepare for President Trump's visit to China to ensure it is a great success

Visiting Vice-Premier Liu Yandong, right, speaks with Jared Kushner, senior White House adviser, center, and Ivanka Trump, left, daughter of US President Donald Trump also serving as an adviser, in Washington DC, on Sept 27, 2017

Liu addressed a reception celebrating the 68th anniversary of the founding of the People's Republic of China at the Chinese embassy on WednesdayEach day hundreds of Sierra Leone residents line up outside Peace Ark waiting for their turn to be diagnosed by Chinese doctors, the report said, noting that at least 2,000 residents would receive medical services during the ship's eight-day stay in Freetown

The Peace Ark left a naval port in China's Zhejiang province on July 26 to carry out its 155-day goodwill missionIt docked in Djibouti from August 23 to 31 and treated thousands of locals, Xinhua said, and made stops in Spain and Sri Lanka for resupply

One of the world's largest hospital ships, the Peace Ark is 178 meters longSince it was commissioned in 2008, the vessel has visited 31 countries, providing free medical services to tens of thousands of people