What the scientists are saying…
Napping linked to dementia
People who nap a lot during the daytime are more likely to go on to get Alzheimer’s, and those who already have the disorder tend to nap more than is typical for their age, a cohort study has found. Researchers at Brigham and Women’s Hospital in the US tracked 1,400 volunteers with an average age of 81 over more than a decade. For up to two weeks each year, they wore a watch that logged their daytime napping patterns. They also took yearly cognitive tests. Overall, those who napped more than an hour a day were found to have a 40% higher risk of getting Alzheimer’s than those who did not nap daily or who napped for less than an hour. The reason for this link is unclear – it might be that dementia disrupts the body’s natural rhythms, or that naps are a sign of existing health problems that raise the risk of dementia. “If you’re not naturally a napper and you start napping frequently, or having long naps, you should be cautious and pay attention – that might be telling you something,” said co-lead author Dr Yue Leng.
Our disappearing orchards
Traditional orchards are disappearing from the landscape, a study has found, uprooted to make way for housing or to create farmland. Researchers used artificial intelligence to compare the distribution of orchards on historic maps with modern ones. They found that in 1900, there were about 100,000 hectares (250,000 acres) of traditional orchards across England and Wales, down to around 20,000 hectares now – a fall-off of 80%. Even if you include commercial orchards, which are less rich in flora and fauna, the amount of space devoted to orchards has halved. Unsurprisingly, the losses have been greatest in urban areas: London has lost 84% of its traditional orchards, defined by the report as sites where at least five trees are managed in a low-intensity way, and the grass is grazed or mowed with minimal chemical input. Their disappearance is our loss, but also nature’s, said Tom Dommett, head of historic environment at the National Trust, which compiled the report. “These orchards can be great places for wildlife like flies and bees, with the gnarled trunks and branches creating the perfect home for rare species.”
We forget the stuff we Google
The easier it is to look up a fact on Google, the more likely we are to forget it, a study has suggested. For the study, published in the Journal of Experimental Psychology: Applied, 101 students were shown a creditcard advert vaunting various benefits, such as 0% APR. Some participants were told before seeing the advert that they’d be able to look up the card online, and were given the search terms to do so efficiently (“globe rewards credit card”). The others were told that to get information about the card, they’d need to email the card company, and were given the relevant address. When both groups were asked about the card, those who’d known they’d be able to Google it had forgotten more about its benefits than those in the second group. However, they could still remember the search terms that would help them find the card online. It has been suggested that the ease with which we can now find information online is degrading our memories; but the study authors think the Google group were actually demonstrating what is known as “cognitive miserliness” – the general tendency in people to conserve mental energy whenever possible.
Dirty air hampers solar farms
Air pollution cost India almost a third of its solar-power potential between 2001 and 2018, researchers have found. India has some of the most polluted cites in the world, and toxic air is known to be killing millions of people a year. But what has been less examined until now is its impact on India’s ability to meet its renewable energy targets. According to a team at the Indian Institute of Technology, air pollution is reducing the capacity of India’s solar panels in two ways: particulate matter is blocking sunlight, reducing the amount that reaches the panels, in a process called atmospheric attenuation; secondly, particulates are building up on the panels, blocking light in what is known as the soiling effect. Using modelling, the researchers calculate that pollution in the worst-affected areas is reducing the energy output of some panels by 50%. The overall loss of capacity is believed to be worth hundreds of millions of dollars a year.