Using magnets to clean PFAS contaminated water
The University of Queensland has developed a simple, fast, and effective new technique to remove 95% of per-and-polyfluoroalkyl substances (PFAS) from contaminated water – in under a minute.
PFAS are synthetic chemicals found in firefighting foams and consumer products like food packaging, cookware, and clothing. They’re very resistant to chemical and biological degradation, hence why they’re sometimes known as “forever chemicals”. As a result, PFAS foam can soak into the ground after rainfall and contaminate groundwater.
There’s still a lot that’s unknown about the health and environmental impacts of PFAS, so having effective techniques to remove PFAS chemicals from contaminated waters is essential.
“Existing methods require machinery like pumps, take a lot of time and need their own power source,” explains Dr Cheng Zhang, a polymer chemist at the Australian Institute for Bioengineering and Nanotechnology, and senior author of the study published in the journal Angewandte Chemie International Edition (Applied Chemistry).
“Our method shows it is possible to remove more of these chemicals in a way that is faster, cheaper, cleaner, and very simple.
“Because our process does not need electricity, it can be used in remote and off-grid communities.”
Read more: Explainer: what are PFAS?
The new PFAS removal technique involves treating contaminated water with a new solution called magnetic fluorinated polymer sorbent.
“This solution that we developed coats the PFAS particles and then we can use a magnet to attract, isolate and remove them,” explains Zhang.
“The solution itself can be reused up to 10 times.
“Our team will now scale up the testing and we hope to have a commercially available product ready in the next three years.”
Could microalgae be the key to feeding the world’s growing population?
Would you eat algae for dinner? Microalgae and other microscopic plant-like organisms could provide a more sustainable and efficient food source alternative to our current agricultural systems, according to an American study.
“Many of us have known the potential of algae for food for years, and have been working on it as a food source, but now, with climate change, deforestation, and a population of eight billion people, everyone realises that the world simply has to become more efficient in protein production,” says co-author Dr Stephen Mayfield, a professor of biology at the University of California, San Diego, and director of the California Centre for Algae Biotechnology.
The researchers analysed current scientific literature and found algae can produce 167 times more useful biomass than corn while using the same amount of land.
“The biggest advantage is the protein production per acre,” Mayfield notes.
“Algae simply dwarf the current gold standard of soybean by at least 10 times, maybe 20 times, more production per acre.”
Some algal species can even be grown in brackish or salty water, meaning that freshwater can be reserved for other uses, and many species are rich in vitamins, minerals, and macronutrients essential to the human diet – like amino acids and omega-3 fatty acids.
“The only way to avoid a really bleak future is to start transitioning now to a much more sustainable future, and algae as food is one of those transitions that we need to make,” concludes Mayfield.
The study has been published in the journal Frontiers in Nutrition.
There’s no “one-size-fits-all” when it comes to the music people fall asleep to
Throughout history, lullabies have been used to help children sleep, and nowdue to the accessibility of recorded music, many people listen to music to help them nod off. This raises the question: does the music people choose to fall asleep to share certain universal characteristics?
Research on the characteristics of sleep music is pretty limited, but a new study in the journal PLOS ONE has identified that sleep music is usually quieter and slower than other music, more often lacks lyrics and features acoustic instruments.
Researchers analysed 225,626 tracks from 985 playlists on Spotify that are associated with sleep, using Spotify’s API to compare the audio features of the sleep tracks to audio features of music from a dataset representing music in general.
They found that the musical features of sleep music were also quite diverse and identified six distinct subcategories. Interestingly, music in three of these subcategories was louder, had a higher degree of energy than average sleep music, and included popular songs.
The authors speculate that, despite their higher energy, popular songs could potentially aid relaxation and sleep for some people through their familiarity. However, more research will be needed to explore this possibility and identify the various reasons different people choose different music for sleeping.
Flower patterns make bumblebees more efficient
Many flowers have colourful patterns, known as nectar guides in biology, that are assumed to show pollinating insects the shortest route to their nectar-producing structures. This could increase the efficiency of the insects in their search for food, while also improving pollen dispersal for the plant.
Now, a new study has identified, for the first time, the individual steps that do this with terrestrial bumblebees (Bombus terrestris), demonstrating that nectar guides cut down the time needed for a bee to interact with a flower by up to 30%.
The research, which has been published in the journal Functional Ecology, was done using video tracking of bumblebees’ visits to artificial flowers that contained nectar and which had different pattern types, or none at all.
But surprisingly, they found that flower patterns don’t actually shorten the time taken by bees to search out nectar after landing. Instead, they act like markings on a runway to help bumblebees coordinate their approach to the flower – shortening the approach flight time and ensuring a favourable landing position.
Flower patterns also shorten the time until take-off, with insects staying significantly less time on patterned flowers after collecting nectar.
“Bumblebees very often run to the edge of the petals for take-off,” explains co-author Dr Johannes Spaethe, an entomologist from the Department of Behavioural Physiology and Sociobiology (Zoology II) at the University of Würzburg, Germany.
“They may find this take-off site more quickly if they can orient themselves to a pattern.”
The authors conclude that “these insights open up new questions on how deceptive patterns or altered displays on ornamental flowers impact foraging efficiency in insect pollinators.”
Imma Perfetto is a science journalist at Cosmos. She has a Bachelor of Science with Honours in Science Communication from the University of Adelaide.
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