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Following your gut. Losing your appetite. A gutsy move. Though we often consider the gut as merely a digestive tool, these common expressions reflect the central role the gut plays in a much wider range of essential functions.

The entire digestive tract is lined by the enteric nervous system (ENS), a vast network of millions of neurons and glial cells—the two primary cell types also found in the central nervous system. While often called the second brain, the ENS not only generates the same neurotransmitters but actually predates the evolution of the central nervous system in the brain.

The functions of the ENS are crucial to life and extend far beyond digestion, as it regulates immunity, gut secretions, and enables complex, bi-directional communication between the gut and the brain. This is why a happy gut co-exists with a happy brain, and why digestive issues can lead to changes in mood and behavior.

As the universe evolves, scientists expect large cosmic structures to grow at a certain rate: dense regions such as galaxy clusters would grow denser, while the void of space would grow emptier.

But University of Michigan researchers have discovered that the rate at which these grow is slower than predicted by Einstein’s Theory of General Relativity.

They also showed that as dark energy accelerates the ’s global expansion, the suppression of the cosmic structure growth that the researchers see in their data is even more prominent than what the theory predicts. Their results are published in Physical Review Letters.

Is time travel possible, and if it is, what sort of civilizations would result? We’ll explore the science that might permit it as well as the classic science fiction examples to see if they make sense.

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Scientists investigating the possible health effects of microplastics have uncovered some disturbing initial results in an experiment based on mice.

When old and young rodents drank microscopic fragments of plastic suspended in their water over the course of three weeks, researchers at the University of Rhode Island found traces of the pollutants had accumulated in every organ of the tiny mammal’s body, including the brain.

The presence of these microplastics was also accompanied by behavioral changes akin to dementia in humans, as well as changes to immune markers in the liver and brain.