Suzannah Lyons

Earth recycles ocean floor into diamonds

Is the sparkler on your finger recycled seabed? Photo: Flickr CC/Stephen Durham

Most diamonds are made of cooked seabed.

The diamond on your finger is most likely made of recycled seabed cooked deep in the Earth.

Traces of salt trapped in many diamonds show the stones are formed from ancient seabeds that became buried deep beneath the Earth’s crust, according to new research led by Macquarie University geoscientists.

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It’s not just fish, plastic pollution harms the bacteria that help us breathe

Plastic pollution can harm both the micro and macro-organisms living in our oceans. Photo: Kevin Krejci

Ten per cent of the oxygen we breathe comes from just one kind of bacteria in the ocean.

Now laboratory tests have shown that these bacteria are susceptible to plastic pollution, according to a study published in Communications Biology tonight.

“We found that exposure to chemicals leaching from plastic pollution interfered with the growth, photosynthesis and oxygen production of Prochlorococcus, the ocean’s most abundant photosynthetic bacteria,” says lead author and Macquarie University researcher Dr Sasha Tetu.

“Now we’d like to explore if plastic pollution is having the same impact on these microbes in the ocean.”

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Building farms and towers at sea to feed and power the world

As partners in the $329 million Blue Economy CRC announced in Launceston

Chief investigators from Macquarie L-R: Dr Fatemeh Salehi, Professor Darren Bagnall, Dr Ming Li, Dr Rouzbeh Abbassi

Macquarie University engineers will develop new technologies for ocean infrastructure as part of the Blue Economy Cooperative Research Centre announced by Karen Andrews, the Minister for Industry, Science and Technology.

The Blue Economy CRC will drive an evolution in marine-based industries, unlocking enormous economic, environmental and technological benefits in aquaculture and renewable energy in Australia’s maritime zone.

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A polariton filter turns ordinary laser light into quantum light

Nature Materials paper Tuesday, 19 February 2019

Artist’s impression of the polaritonic photon conversion platform. Laser photons enter through the top mirror and leave through the bottom mirror exhibiting quantum ‘granularity’ – after interacting with the semiconductor layer. Image: Andrew Wood

An international team of researchers led out of Macquarie University has demonstrated a new approach for converting ordinary laser light into genuine quantum light.

Their approach uses nanometre-thick films made of gallium arsenide, which is a semiconductor material widely used in solar cells. They sandwich the thin films between two mirrors to manipulate the incoming photons.

The photons interact with electron-hole pairs in the semiconductor, forming new chimeric particles called polaritons that carry properties from both the photons and the electron-hole pairs. The polaritons decay after a few picoseconds, and the photons they release exhibit distinct quantum signatures.

The teams’ research was published overnight in the journal Nature Materials.

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Trees remember heatwaves

Eucalyptus grandis

The flooded gum or rose gum (Eucalyptus grandis). Photo: Geoexplore

An Aussie eucalypt can ‘remember’ past exposure to extreme heat, which makes the tree and its offspring better able to cope with future heatwaves, according to new research from Macquarie University.

This finding could have important implications for restoring ecosystems and climate-proofing forestry, as the number of hot days and heatwaves increase due to climate change.

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The Milky Way is warped

A slightly exaggerated impression of the real shape of our warped and twisted Milky Way. Image: Xiaodian Chen (National Astronomical Observatories, Chinese Academy of Sciences)

The first accurate 3D map of our galaxy reveals its true shape: warped and twisted.

Background information and further images below.

Astronomers from Macquarie University and the Chinese Academy of Sciences have used 1339 ‘standard’ stars to map the real shape of our home galaxy in a paper published in Nature Astronomy today.

They found the Milky Way’s disc of stars becomes increasingly ‘warped’ and twisted the further away the stars are from the galaxy’s centre.

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Cane toads: what they do in the shadows

A juvenile cane toad (Rhinella marina) in Emma Gorge, Western Australia. Photo: M.G. Swan

Cane toads are picking up some shady habits, according to a new study co-authored by a Macquarie University researcher.

Toads in Western Australia have been spotted awake and active during the day in deeply shaded habitats, despite the species usually being nocturnal in Australia and other parts of the world.

However nearby cane toad populations at more exposed sites remained only active at night.

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Promiscuous females and their role in evolution

A promiscuous female fruit fly (Drosophila melanogaster) marked with paint. Photo: The Wigby Lab

Males have to make less of an effort to mate with promiscuous female fruit flies, making the quality and quantity of their semen all the more important in the competition to fertilise the females’ eggs.

This also leads to male flies repeatedly mating with the same female, according to a paper published overnight in Nature Communications, by researchers from Macquarie University, the University of Oxford and the University of East Anglia, who looked into the eyes of thousands of fruit flies.

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The quest for the missing proteins in rice

Rice (Oryza sativa) is the major food source for more than half the world’s population. Photo: Pille-Riin Priske/Unsplash CC

Researchers have identified over 5,700 new proteins in rice and are calling for a global effort to find the remaining missing proteins, in a new study co-authored by Macquarie University.

The international team of scientists from Australia, Iran and Japan say there’s an estimated 35,000 proteins encoded by the rice genome, and yet we still don’t have experimental evidence for 82 per cent of them.

This is important because rice is the major food source for more than half the world’s population, and in order for it to grow in warmer climates and with less water we will need to better understand rice at the molecular level. [continue reading…]

Friend or foe: how do you feel about the insects and spiders living in your home?

A jumping spider commonly found in Australian backyards. Photo: Jim McLean

Do you love or loathe your creepy-crawly house guests? Are you an insecticide at the ready kind of person? Or do you take a more live and let live approach?

Researchers from Macquarie University and the University of Sydney want to know about the insects and spiders living in and around your home, how you feel about them, and what you do to control them.  [continue reading…]