1. Nowadays, the replacements of knee and hip joints are two of the most common artificial joint replacement operations. And many countries including China are coming up with 3D printed versions as an alternative.
2. his is the magical moment when a set of twins in the US hear their mother clearly for the first time, thanks to new hearing aids.
3. In the Iranian capital Tehran, a classic cars show has gathered fervent fans and car owners who got there to have a closer look at all the big and small rides in one place.