Health & Science
The Romans’ concrete secret
Seawalls and piers built by the Romans 2,000 years ago are sturdier than modern versions, and haven’t been eroded by seawater. Scientists have finally figured out why. To unlock the secret, an international team of researchers analyzed the chemical makeup of Roman-era marine structures off the Italian coast. Advanced imaging techniques and spectroscopic tests revealed that the Roman recipe for concrete included volcanic ash, rock, lime (calcium oxide), and seawater. This mixture produces a rare chemical reaction that creates two minerals—aluminous tobermorite and phillipsite—that essentially reinforce the concrete when it’s exposed to the sea. “Contrary to the principles of modern cement-based concrete, the Romans created a rock-like concrete that thrives in open chemical exchange with seawater,” lead author Marie Jackson tells BBC.com. “It’s a very rare occurrence in the Earth.” Jackson and her team are now working to reverse-engineer the Roman-era concrete, in order to construct more-durable seawalls.
Smart people live longer
People with high IQs enjoy many advantages in life, and new research suggests greater longevity is one of them. A team at the University of Edinburgh looked at health data for over 75,000 people born in Scotland in 1936, all of whom took standardized intelligence tests at age 11. The researchers found that over the 68-year study period, ending in 2015, those with higher IQ scores were likely to live longer than their peers. Greater intelligence was linked with a 28 percent lower risk of death from lung disease, a 25 percent drop in the risk for heart disease, and a 24 percent lower risk for stroke. The kids with higher IQs were also less likely to die from injuries, digestive disease, dementia, or smoking-related cancers—regardless of their sex or socioeconomic status. The researchers speculate that people with higher IQs are more likely to take care of their health, leading them to exercise more, smoke less, and seek out medical attention when they need it. “We don’t know yet why intelligence from childhood and longevity are related, and we are keeping an open mind,” researcher Ian Deary tells The New York Times. “Lifestyles, education, deprivation, and genetics may all play a part.”
A tenth planet?
Just 18 months after scientists claimed they had found evidence of a ninth planet lurking deep in the outer solar system, another group of researchers says it has found a 10th, reports Newsweek.com. In January last year, a team at Caltech in California said the peculiar orbits of several newly discovered dwarf planets and other objects were most likely caused by a massive Neptunesize planet—a “planetary mass object” the team dubbed “Planet Nine.” Now researchers at the University of Arizona have suggested that the orbits of more than 600 frozen space rocks in the Kuiper Belt—a region beyond Neptune filled with icy asteroids, comets, and dwarf planets— indicate the presence of another previously unknown planet. They believe “Planet Ten” is much smaller than Planet Nine—the mass of Mars, rather than Neptune— and significantly closer to Earth. Both planets remain hypothetical for now, because no one has actually seen them. But researchers hope to confirm their suspicions when the Large Synoptic Survey Telescope, currently under construction in Chile, comes online in 2020. “We have a good sense of the outer solar system,” says Kat Volk, who co-authored the latest study. “But it would not surprise me at all if there are very distant things we have missed.”
Health scare of the week
Disinfectant and superbugs
Triclosan, a widely used disinfectant, may be contributing to the rise of drug-resistant bacteria, reports LiveScience.com. The antimicrobial agent has been banned from household soaps in the U.S. and European Union over concerns about its safety and effectiveness. But triclosan is still added to hospital soaps and many other household products, including toothpaste, cosmetics, and toys. When researchers at the University of Birmingham in England conducted lab tests on E. coli, they found that when the bacteria mutated to become resistant to powerful quinolone antibiotics, they also became more resistant to triclosan. “We think that bacteria are tricked into thinking they are always under attack and are then primed to deal with other threats, including triclosan,” says researcher Mark Webber. “The worry is that this might happen in reverse and triclosan exposure might encourage growth of antibiotic- resistant strains.”
Alamy, J.P. Oleson, Heather Roper/LPL ■