Scientists pinpoint the chemicals behind a cat’s signature urine smell - Popular Science

Diseases such as Alzheimer's and frontotemporal dementia are considered neurodegenerative tauopathies, in which tau proteins in the brain misfold and lead to cognitive decline. Until now, it has been unclear how misfolded tau recruits other seemingly healthy tau and causes it to misfold and clump. A new study led by Northwestern University researchers, in collaboration with researchers with the University of California, Santa Barbara, found that tau vulnerable to misfolding carries a single dominant hotspot. That site binds the matching site on a neighboring tau, or on a tau at the end of an existing fibril, and the incoming tau then misfolds to match. The hotspot is hydrated by water that is wrapping over and protecting a hydrophobic site, and releasing that water is what pulls the two together. This finding could help scientists diagnose tauopathies, block misfolded tau from converting other normal tau to misfolded shapes, and design therapeutic solutions in the future.

Lead mining began during the 7th century in Derbyshire, England. Magpie Mine was the last facility to operate in the region. It opened in 1735 and finally closed in 1954. Thanks to some medieval human teeth, archaeologists have pinpointed when lead production first expanded across Europe during the Middle Ages. By examining dental enamel collected from graves located in central England, researchers now know the post-Roman society started mining and smelting again during the mid-7th century. As the team explains in a study published today in the journal Antiquity, the consequences of exposure to the toxic were stark—but distributed unequally among locals.

Lawrence Livermore National Laboratory researcher Isaiah Santistevan led the development of three-dimensional simulations exploring how a nuclear device could deflect or disrupt an asteroid threatening Earth. Credit: Blaise Douros/LLNL Lawrence Livermore National Laboratory (LLNL) researchers are developing three-dimensional simulations to examine how a nuclear device could be used to deflect or potentially disrupt an asteroid threatening Earth.