Two scientists won the Nobel Prize in physiology or medicine on Monday for their discovery of microRNA, tiny bits of genetic material that serve as on and off switches inside cells that help control what the cells do and when they do it.

If scientists can better understand how they work and how to manipulate them, it could one day lead to powerful treatments for diseases like cancer.

The work by Americans Victor Ambros and Gary Ruvkun is "proving to be fundamentally important for how organisms develop and function," according to a panel that awarded the prize in Stockholm.

Ambros and Ruvkun were initially interested in genes that control the timing of different genetic developments, ensuring that cell types develop at the right time.

Their discovery ultimately "revealed a new dimension to gene regulation, essential for all complex life forms," the panel said.

RNA is best known for carrying instructions for how to make proteins from DNA in the nucleus of the cell to tiny cellular factories that actually build the proteins. MicroRNA does not make proteins, but helps to control what cells are doing, including switching on and off critical genes that make proteins.

Last year's Nobel for medicine went to scientists who discovered how to manipulate one of those types of RNA, known as messenger RNA or mRNA, now used to make vaccines for COVID-19.

Ambros' and Ruvkun's revolutionary discovery was initially made in worms; they set out to identify why some kinds of cells didn't develop in two mutant strains of worms commonly used as a research model in science.

"Their groundbreaking discovery revealed a completely new principle of gene regulation that turned out to be essential for multicellular organisms, including humans," according to the citation explaining the importance of their work.

Two pioneers of artificial intelligence - John Hopfield and Geoffrey Hinton - won the Nobel Prize in physics Tuesday for helping create the building blocks of machine learning that is revolutionising the way we work and live but also creates new threats for humanity.

Hinton, who is known as the godfather of artificial intelligence, is a citizen of Canada and Britain who works at the University of Toronto, and Hopfield is an American working at Princeton.

"These two gentlemen were really the pioneers," said Nobel physics committee member Mark Pearce.

The artificial neural networks - interconnected computer nodes inspired by neurons in the human brain - the researchers pioneered are used throughout science and medicine and "have also become part of our daily lives," said Ellen Moons of the Nobel committee at the Royal Swedish Academy of Sciences.

Hopfield, whose 1982 work laid the groundwork for Hinton's, told The Associated Press, "I continue to be amazed by the impact it has had."

Hinton predicted that AI will end up having a "huge influence" on civilization, bringing improvements in productivity and health care.

"It would be comparable with the Industrial Revolution," he said in an open call with reporters and officials of the Royal Swedish Academy of Sciences.

"We have no experience of what it's like to have things smarter than us. And it's going to be wonderful in many respects," Hinton said.

South Korean poet and novelist Han Kang was awarded the Nobel Prize in literature Thursday for a poetic and unsettling body of work that the Nobel committee said "confronts historical traumas and exposes the fragility of human life."

A slow-burning international literary star who has won multiple awards in South Korea and Europe, Han is the first Asian woman and the first South Korean writer to win the Nobel literature prize. She was awarded for books, including "The Vegetarian" and "Human Acts," that explore the pain of being human and the scars of Korea's turbulent history.

Nobel literature committee member Anna-Karin Palm said Han writes about "trauma, pain and loss," whether individual or collective, "with the same compassion and care."

"And this, I think, is something that is quite remarkable," Palm said.

Nobel committee chairman Anders Olsson praised Han's "empathy for the vulnerable, often female lives" of her characters.