One of them might even have a hearing aid. Last week we celebrated Reptile Awareness Day, and now two skink species have been discovered in mid-eastern Queensland. “While this light is dim and unlike the typical photoperiod at lower latitudes, we show that it is sufficient to set a biological clock in krill, showing this animal has one of the more sensitive biological rhythms studied to date.” New skinks on the block “We found that the light environment during the high Arctic polar night has a complex timing of ‘light’ and ‘dark’ due to light coming from the Sun below the horizon, the Moon, and the aurora borealis,” says lead researcher Jonathan Cohen from the University of Delaware, US. The team measured the light intensity during the Arctic winter on the Svalbard archipelago, and found the midday light was only twice as bright as the midnight light – and yet krill still exhibited a strong biological rhythm, coming to the surface to feed at night and sinking back deep to avoid predators in the day.īack in the lab, the researchers discovered that krill are much more sensitive to light at night, allowing them to pick up tiny visual cues. Marine scientists have now figured out how Arctic krill set their daily rhythms. Most animals use the guiding light of the Sun to sync up their body clocks – but what about animals who live at the extremes of the Earth, like the polar winter where the Sun never rises about the horizon? “While there is much more work to be done following our discovery, it at least offers hope that it may in time be possible to prevent or to slow down the disease process.” Mystery of Arctic krill solved “Not only can we see what may happen early on in the disease – long before a patient might experience any symptoms – but we can also begin to see how the disturbances change over time in each cell,” says senior author András Lakatos from Cambridge. The team grew these organoids for 240 days – much longer than previous research had managed – allowing them to observe what happens at the earliest stages of ALS/FTD.
This affects the nerve cells of the brain and spinal cord, causing loss of muscle control, and it commonly occurs at the same time as frontotemporal dementia (FTD). Now, in a study reported in Nature Neuroscience, researchers have grown brain organoids using stem cells from patients with a neurological disorder called amyotrophic lateral sclerosis (ALS). They are being increasingly used to study things like infectious diseases, genetic disorders and cancers in the lab – such as being used to study SARS-Cov-2 infection in the lungs. They are like miniaturised, simplified versions of actual organs, and they function in an organ-like way. Organoids are three-dimensional cell structures derived from stem cells. Researchers at the University of Cambridge, UK, have developed “mini brains” in the lab, which they say can help them study a common form of motor neurone disease. The study is published in Nature Astronomy. “To see the brightness of TW Pictoris plummet in 30 minutes is in itself extraordinary as it has never been seen in other accreting white dwarfs and is totally unexpected from our understanding of how these systems are supposed to feed through the accretion disc.” “The brightness variations seen in accreting white dwarfs are generally relatively slow, occurring on timescales of days to months,” she says.
Lead author Simone Scaringi from Durham University, UK, says this is “extraordinary”. An artist’s impression example of a white dwarf – in this image the white dwarf MV Lyrae – accreting as it draws in material from a companion star.
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