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Detection of an Earth-sized exoplanet orbiting the ultracool dwarf star SPECULOOS-3

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Detection of an Earth-sized exoplanet orbiting the ultracool dwarf star SPECULOOS-3


The SPECULOOS project, led by the astronomer Michaël Gillon from the University of Liège, has just discovered a new Earth-sized exoplanet around SPECULOOS-3, an “ultracool dwarf” star as small as Jupiter, twice as cold as our Sun, and located 55 light-years from Earth. After the famous TRAPPIST-1, SPECULOOS 3 is the second planetary system discovered around this type of star.

Ultra-cool dwarf stars are the least massive stars in our Universe, similar in size to Jupiter, more than twice as cold, ten times less massive and a hundred times less luminous than our Sun. Their lifespan is over a hundred times longer than that of our star, and they will be the last stars to shine when the Universe becomes cold and dark. Although they are far more common in the Cosmos than Sun-like stars, ultra-cool dwarf stars are still poorly understood due to their low luminosity. In particular, very little is known about their planets, even though they represent a significant fraction of the planetary population of our Milky Way.

It’s against this backdrop that the SPECULOOSconsortium, led by the University of Liège, has just announced the discovery of a new Earth-sized planet orbiting a nearby ultra-cool dwarf star. The SPECULOOS-3 b exoplanet lies around 55 light-years from Earth (which is very close on a cosmic scale! Our galaxy, the Milky Way, stretches over 100,000 light-years). SPECULOOS 3 is only the second planetary system to be discovered around this type of star: “SPECULOOS-3 b is practically the same size as our planet,” explains the astronomer Michaël Gillon, first author of the article published in Nature Astronomy. A year, i.e. an orbit around the star, lasts around 17 hours. Days and nights, on the other hand, should never end. We believe that the planet rotates synchronously, so that the same side, called the day side, always faces the star, just like the Moon does for the Earth. On the other hand, the night side hand, would be locked in endless darkness.”

The SPECULOOS (Search for Planets EClipsing ULtra-cOOl Stars) project, initiated and led by astronomer Michaël Gillon, has been specially designed to search for exoplanets around the nearest ultra-cold dwarf stars. These stars are scattered across the sky, so you must observe them one by one, over a period of weeks, to have a good chance of detecting transiting planets,” continues the researcher. This requires a dedicated network of professional robotic telescopes.” This isthe concept behind SPECULOOS, jointly run by the Universities of Liège, Cambridge, Birmingham, Berne, MIT and ETH Zürich.

“We designed SPECULOOS specifically to observe nearby ultra-cool dwarf stars in search of rocky planets that lend themselves well to detailed studies,” comments Laetitia Delrez, astronomer at the University of Liège. In 2017, our SPECULOOS prototype using the TRAPPIST telescope discovered the famous TRAPPIST-1 system made up of seven Earth-sized planets, including several potentially habitable ones. This was an excellent start!”

The SPECULOOS-3 star is more than twice as cold as our sun, with an average temperature of around 2,600°C. Due to its hyper-short orbit, the planet receives almost sixteen times more energy per second than the Earth does from the Sun and is therefore literally bombarded with high-energy radiation. “In such an environment, the presence of an atmosphere around the planet is highly unlikely,” says Julien de Wit, MIT professor and co-director of the SPECULOOS Northern Observatory and its Artemis telescope, co-developed by the University of Liège and MIT, and the mainstay of this discovery. The fact that this planet has no atmosphere could be a plus in several respects. For example, it could enable us to learn a great deal about ultra-cool dwarf stars, which in turn will make possible more in-depth studies of their potentially habitable planets.”

SPECULOOS-3 b is proving to be an excellent target for the JWST space telescope, to be launched in 2021, whose data will revolutionize our vision of the Universe. “With the JWST, we could even study the mineralogy of the planet’s surface!” enthuses Elsa Ducrot, a former researcher at the University of Liège now based at Paris Observatory.

“This discovery demonstrates the ability of our SPECULOOS-North observatory to detect Earth-sized exoplanets suitable for detailed study. And this is just the beginning! Thanks to the financial support of the Walloon Region and the University of Liège, two new telescopes, Orion and Apollo, will soon join Artemis on the plateau of the Teide volcano in Tenerife, to speed up the hunt for these fascinating planets” concludes Michaël Gillon.



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Orchids support seedlings through ‘parental nurture’ via shared underground fungal networks

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Orchids support seedlings through ‘parental nurture’ via shared underground fungal networks


The Common Spotted Orchid (Dactylorhiza fuchsii) is found all over the UK. These orchids produce tiny seeds that can be carried anywhere by the wind, yet they often appear in clumps with small seedlings growing near mature plants. This phenomenon has puzzled ecologists since Darwin’s time, with the exact reason remaining a mystery.

A new study, led by researchers from the University of Sheffield in collaboration with The University of Manchester, provides the first evidence that early stage orchid seedlings germinate and thrive near to adult plants due to a kind of parental nurture using underground fungal networks.

Scientists investigated the idea that fungal networks, known as mycorrhizal networks, act as a direct pathway for established orchid plants to share recently produced sugars with developing seedlings.

Professor Katie Field, co-author of the study and Professor of Plant-Soil Processes at the University of Sheffield’s School of Biosciences, said: “Our results support the idea that some orchids engage in a form of ‘parental nurture’ with their seedlings. By supplying early stage seedlings with essential nutrients via shared fungal connections, the parent orchids give the seedlings an advantage over neighbouring plants that are competing for the same resources.

“This finding is exciting because why these orchids are often found in clumps, despite their seeds being wind dispersed, has been a puzzle for hundreds of years.”

The study focused on the Common Spotted Orchid and its fungal partner, Ceratobasidium cornigerum. Researchers created a system where mature, green orchids were connected to developing, chlorophyll-free seedlings through a fungal network grown on agar.

The mature plants were then exposed to a special form of carbon dioxide that could be tracked within the system.

Here’s how it worked:

  • Green orchid plants were connected to developing seedlings through the fungal network.
  • The green plants were then exposed to a special form of carbon dioxide that could be tracked within the system.
  • After a period of time, the researchers analysed both the seedlings and the fungal network to see where the labelled carbon ended up.

The results were clear, the seedlings were accumulating the labelled carbon, indicating they were being supported by the adult plants. By tracking the movement of carbon, the study showed that the mature orchids were indeed sharing their recently produced sugars with the seedlings through the fungal network.

Sir David Read, Emeritus Professor of Plant Sciences from the University of Sheffield and lead author of the study, said: “Whereas the seeds of most plants, for example legumes (peas, beans) and grasses (rice, corn, wheat) are fully provisioned with food reserves by their parent plants, the so-called dust seeds of orchids receive insufficient reserves from the parents to develop on their own.

“They are instead produced in their millions by each individual parent orchid plant from which they are dispersed, by wind, to the surrounding environment. Even Charles Darwin was puzzled by this strategy, suggesting that while it should enable the seeds of an individual orchid plant to be so widely distributed that within a few years it could colonise the whole world. He observed that their failure to do so ‘could not be understood at this time’.

“What is now revealed is that the belowground development of these essentially reserve-free seeds can be supported by photosynthetically produced sugars that are transported to them from mature plants growing above ground through a shared mycelium of symbiotic fungi.”

Results of the study, published in New Phytologist, show the amount of carbon transferred seemed to depend on the environment. When the fungus had access to a richer food source (oatmeal agar), less carbon was transferred to the seedling. This suggests that the strength of the demand from the seedlings may influence the flow of nutrients through the network.

This research has important implications for understanding orchid ecology and conservation efforts. By recognising the importance of fungal connections, scientists can develop better strategies for protecting these unique and often threatened plants.

Next steps are to research this theory in the natural habitat that the orchids are found in and to look at whether this applies to other species.



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Bird flu: Diverse range of vaccines platforms ‘crucial’ for enhancing human pandemic preparedness

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Bird flu: Diverse range of vaccines platforms ‘crucial’ for enhancing human pandemic preparedness


Vaccination remains the most effective strategy for avian influenza prevention and control in humans, despite varying vaccine efficacy across strains.

That’s according to the authors of a new review which delves into existing research into bird flu vaccines for humans.

Published in the peer-reviewed journal Human Vaccines & Immunotherapeutics, the results of the paper are particularly timely following news last week (Wednesday 22nd May) that the bird flu strain H5N1 had once again, for a second time, jumped from cattle in America to a human — prompting fears of subsequent human-to-human infection, with possible critical consequences.

Instances of the avian influenza were first recognized in US cattle in March. Since then, this strain has mainly spread from cow-to-cow and scientists have discovered very high levels of virus in raw milk (pasteurized milk is safe, having shown viral RNA but not infectious virus). To-date two people, however, are known to have contracted the bird flu virus. Both patients — US farmers — only reported eye symptoms and with treatment they made a full recovery.

Following tests on the first human instance, it was seen that the strain had mutated to be better adapted to mammalian cells, but as long as that human didn’t pass it onto another person it likely stopped the spread at that point. With the second case, the CDC has released a statement to say it has been monitoring influenza surveillance systems intently, especially in impacted states. “There has been no sign of unusual influenza activity in people, including in syndromic surveillance,” they report.

The concern now, though, is that if H5N1 continues to be given the environment in which to mutate (such as in close quarter cattle farms) — and this continues long enough — it has the potential to find a combination that will easily spread to humans.

The results of this new research, carried out by a team at the University of Georgia, USA, suggests vaccines still remain our “primary defense” against potential spread of avian influenzas such as the H5N1 and others assessed.

“The H5N1, H7N9, and H9N2 subtypes of avian influenza virus pose a dual threat, not only causing significant economic losses to the global poultry industry but also presenting a pressing public health concern due to documented spillover events and human cases,” explains lead author Flavio Cargnin Faccin, who alongside his mentor Dr. Daniel Perez of the University of Georgia, USA, analyzed the current landscape of research into human vaccines for these bird flus.

“This deep delve into the landscape of avian influenza vaccines for humans shows vaccination remains the primary defense against the spread of these viruses.”

The team examined studies of vaccines tested in mice, ferrets, non-human primates, and clinical trials of bird flu vaccines in humans, and assessed both established platforms and promising new directions.

The review carried out suggests inactivated vaccines are a safe and affordable option that primarily activate humoral immunity — the part of our immune system that produces antibodies.

Live attenuated influenza vaccines (LAIVs) are known to induce a wider immune response than inactivated vaccines, activating not only antibody production but also mucosal and cellular defenses. In this review, the authors suggest this broader response may offer greater protection, though, the authors suggest further research is needed to fully understand and harness its potential benefits for both human and agricultural applications.

The review also examined alternatives, such as virus-like particle (VLP) vaccines and messenger RNA (mRNA) vaccines, that have emerged more recently. Although VLP vaccines for bird flu have limited clinical trial data in humans, results from studies in mice and ferrets showed promise, the authors found. mRNA vaccines against H5N1 and H7N9 bird flu subtypes also generated a rapid and strong immune response in mice and ferrets, and, while data in humans is scarce, results from a phase 1 study of an H7N9 mRNA vaccine in healthy humans were “encouraging.”

Overall, the team suggests “exploring and employing a diverse range of vaccine platforms,” will be “crucial for enhancing pandemic preparedness and mitigating the threat of avian influenza viruses.”



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When should you neuter or spay your dog?

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When should you neuter or spay your dog?


Researchers at the University of California, Davis, have updated their guidelines on when to neuter 40 popular dog varieties by breed and sex. Their recent paper in Frontiers in Veterinary Science adds five breeds to a line of research that began in 2013 with a study that suggested that early neutering of golden retrievers puts them at increased risk of joint diseases and certain cancers.

That initial study set off a flurry of debate about the best age to neuter other popular breeds. Professors Lynette and Benjamin Hart of the School of Veterinary Medicine, the study’s lead authors, set out to add more breed studies by examining more than a decade of data from thousands of dogs treated at the UC Davis veterinary hospital. Their goal was to provide owners with more information to make the best decision for their animals.

They specifically looked at the correlation between neutering or spaying a dog before 1 year of age and a dog’s risk of developing certain cancers. These include cancers of the lymph nodes, bones, blood vessels or mast cell tumors for some breeds; and joint disorders such as hip or elbow dysplasia, or cranial cruciate ligament tears. Joint disorders and cancers are of particular interest because neutering removes male and female sex hormones that play key roles in important body processes such as closure of bone growth plates.

For the most recent study, they focused on German short/wirehaired pointer, mastiff, Newfoundland, Rhodesian ridgeback and Siberian husky. Data was collected from the UC Davis veterinary hospital’s records that included more than 200 cases for each of these five breeds weighing more than 20 kg (or 44 pounds), spanning January 2000 through December 2020.

The Harts said their updated guidelines emphasize the importance of personalized decisions regarding the neutering of dogs, considering the dog’s breed, sex and context. A table representing guidelines reflecting the research findings for all 40 breeds that have been studied, including the five new breeds, can be found here.

Health risks different among breeds

“It’s always complicated to consider an alternate paradigm,” said Professor Lynette Hart. “This is a shift from a long-standing model of early spay/neuter practices in the U.S. and much of Europe to neuter by 6 months of age, but important to consider as we see the connections between gonadal hormone withdrawal from early spay/neuter and potential health concerns.”

The study found major differences among these breeds for developing joint disorders and cancers when neutered early. Male and female pointer breeds had elevated joint disorders and increased cancers; male mastiff breeds had increased cranial cruciate ligament tears and lymphoma; female Newfoundland breeds had heightened risks for joint disorders; female Ridgeback breeds had heightened risks for mast cell tumors with very early neutering; and Siberian huskies showed no significant effects on joint disorders or cancers.

“We’re invested in making contributions to people’s relationship with their animals,” said Benjamin Hart, distinguished professor emeritus. “This guidance provides information and options for veterinarians to give pet owners, who should have the final decision-making role for the health and well-being of their animal.”

Their combined research studies will soon be available with others in the open access journal, Frontiers of Veterinary Science, as a free e-book, Effective Options Regarding Spay or Neuter of Dogs.

Other researchers on this UC Davis study include: Abigail Thigpen, Maya Lee, Miya Babchuk, Jenna Lee, Megan Ho, Sara Clarkson and Juliann Chou with the School of Veterinary Medicine; and Neil Willits with the Department of Statistics.

The research received a small amount of funding from the Center for Companion Animal Health, but was primarily conducted by the above authors as volunteers.



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