Galaxy clusters grow over time under gravity and, in the present-day universe, can contain hundreds or even thousands of galaxies, as well as hot gas and dark matter. As time goes by, their galaxies burn through the fuel available and evolve from vigorously star-forming galaxies into red and dead galaxies.

In the last few decades more has been learned about the impact of oral health on the entire human biological system. And more is being done to reduce factors that lead to an estimated 15 million babiesborn prematurely or preterm (defined as delivery before the 37th week of pregnancy) each year. Preterm babies are at greater risk of experiencing serious health problems.

Due to correlation between preterm births and poor oral care, researchers have looked at various ways to improve dental health during pregnancy, including “deep-teeth cleaning” like scaling and planing to remove plaque and tarter on the teeth and below the gum line, but that hasn't seemed to be very effective.

Our auditory system is able to detect sounds at an implicit level. The brain can distinguish between even very similar sounds, but we do not always recognize these differences. A new study demonstrated using sound perception during passive listening; when the subject is not trying to explicitly hear the differences.

The result was that the human brain unconsciously distinguishes between even very similar sound signals during passive listening.  

The ongoing SARS-CoV-2 pandemic and new mutations in viral genetic sequences have made "variant" part of the cultural lexicon, because they can have significant impacts on the virus’s transmissibility and the damage it causes. 

Researchers have long been concerned that could happen in the HIV-1 virus, which has been mitigated thanks to safer sex practices and modern science but still affects 38 million people worldwide.

This is the third coronavirus pandemic of this century, after SARS and MERS, and due to that many forget that influenza is a chronic killer, 40-60,000 deaths in America alone each year. To mitigate those effects, there is a seasonal flu vaccine. Each year researchers model how they expect the virus to mutate and then they create a vaccine based on that. Some years are more successful than others but if people do get the flu, effects will be reduced.

Our life on earth began in water but how did it 'evolve'?

To get an understanding of the link between the chemistry of carbon and water, scientists can track the various forms, or isotopes, of its constituent hydrogen and oxygen atoms over the history of the universe, like a giant treasure hunt.

Recently, researchers from the CNRS, Paris-Saclay University, the French Alternative Energies and Atomic Energy Commission (CEA), and the University of Pau and the Pays de l’Adour (UPPA), with support from the Muséum National d’Histoire Naturelle (MNHN), have followed the trail of the isotopic composition of water back to the start of the solar system, in the inner regions where Earth and the other terrestrial planets were formed.