A study by the Center for Space Medicine Research at Cedars-Sinai hospital in Los Angeles has found that mini-hearts grown from human stem cells grow better in space than they do on Earth. The heart shrinks, weakens, and changes its shape, becoming circular. However, researchers found that when they tried to grow human mini-heartlets from stem cells on board the ISS, they could produce them more easily and in higher quantities. This could be facilitated by low gravity. The study's director, Arun Sharma, has been sending heart cell experiments to the ISS since 2016 and declined to specify how many more heart organoids the space experiments produced compared to Earth-based reactors. The research suggests that the microgravity environment in space could produce more robust patches less resistant to collapse under Earth-imposed gravity when brought back.