Press freedom, the plight of refugees and climate modelling: 12 men and only one woman won Nobel Prizes this year for conferring "the greatest benefit to humankind".

While four women won Nobel prizes in 2020 -- close to the 2009 record of five -- the awards remain male-dominated as much of the prizewinning work dates back 20, 30 or even 40 years when fewer women reached the top levels of academic research.

In 2019, there was only one woman laureate, and in 2017 and 2016 there were none.

Here are the 2021 winners in each discipline:

Medicine

US scientists David Julius and Ardem Patapoutian won the Medicine Prize for discoveries on receptors for temperature and touch.

Their discoveries "unlocked one of the secrets of nature by explaining the molecular basis for sensing heat, cold and mechanical force," the jury said.

The duo's research, conducted independently of each other in the late 1990s and 2000s, is being used to develop treatments for a wide range of diseases and conditions, including chronic pain.

Economics

Three US-based economists, Canadian-American David Card, Israeli-American Joshua Angrist and Dutch-American Guido Imbens, won the Economics Prize for work on the labour market using "natural experiments", or observational cause-and-effect studies, that have revolutionised empirical research in the field.

Card's work has focused on the labour market effects of minimum wages, immigration and education.

Meanwhile, Angrist and Imbens figured out a methodological way to interpret data from "natural experiments", demonstrating how precise cause and effect conclusions can be.