Mouse embryos grown without eggs or sperm: why and what’s next?

Two research teams grew synthetic embryos using stem cells, long enough to see some organs develop.

Cassandra Willyard

Nature | August 25, 2022

Natural and synthetic mouse embryos grown by developmental biologist Magdalena Zernicka-Goetz’s research group.Credit: Gianluca Amadei, Charlotte Handford

The recipe for mammalian life is simple: take an egg, add sperm and wait. But two new papers demonstrate that there’s another way. Under the right conditions, stem cells can divide and self-organize into an embryo on their own. In studies published in Cell1 and Nature2 this month, two groups report that they have grown synthetic mouse embryos for longer than ever before. The embryos grew for 8.5 days, long enough for them to develop distinct organs — a beating heart, a gut tube and even neural folds.

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‘Unsustainable’: how satellite swarms pose a rising threat to astronomy

SpaceX and other companies are still struggling to make their satellites darker in the night sky.

Alexandra Witze

Nature | May 26, 2022

Starlink satellites streak (vertically) across a time-lapse photo of the night sky near Carson National Forest, New Mexico.Credit: M. Lewinsky (CC BY 2.0)

It’s been three years since SpaceX, an aerospace company in Hawthorne, California, launched its first batch of Starlink Internet-communication satellites, sparking concern among astronomers about the streaks the satellites leave in photographs of the night sky. Since then, many other Starlinks have launched: more than 2,300 of them now orbit Earth, comprising nearly half of all operational satellites.

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The countries maintaining research ties with Russia despite Ukraine

Many Western nations are severing scientific links — but it’s a different story in China, India and South Africa.

Smriti Mallapaty , T. V. Padma , Emiliano Rodríguez Mega , Richard Van Noorden & Ehsan Masood

A research reactor at Russia’s Konstantinov Institute of Nuclear Physics near St Petersburg.Credit: Peter Kovalev/ITAR-TASS/Alamy

Is Russia’s invasion of Ukraine redrawing the map of international scientific cooperation? Whereas Europe and the United States are swiftly moving to cut long-standing ties, the governments of China, India, South Africa are maintaining links.

They are members of the BRICS, a group of five countries — including Brazil and Russia — that work together to promote trade and economic development, and have an active programme of scientific cooperation. Last year, researchers from the 5 nations organized some 100 meetings under the BRICS umbrella in a spectrum of fields including astronomy, climate and energy, health and medicine.

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Global, regional, and national consumption of animal-source foods between 1990 and 2018: findings from the Global Dietary Database

Victoria Miller, PhD; Julia Reedy, MS; Frederick Cudhea, PhD; Jianyi Zhang, PhD; Peilin Shi, PhD; Josh Erndt-Marino, PhD; Jennifer Coates, PhD; Renata Micha, PhD; Prof Patrick Webb, PhD; Prof Dariush Mozaffarian, MD; on behalf of the Global Dietary Database

The Lancet | Open Access | Published: March, 2022 | DOI:https://doi.org/10.1016/S2542-5196(21)00352-1

Summary
Background
Diet is a major modifiable risk factor for human health and overall consumption patterns affect planetary health. We aimed to quantify global, regional, and national consumption levels of animal-source foods (ASF) to inform intervention, surveillance, and policy priorities.

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Your brain expands and shrinks over time — these charts show how

Based on more than 120,000 brain scans, the charts are still preliminary. But researchers hope they could one day be used as a routine clinical tool by physicians.

Max Kozlov

Nature | April 06, 2022

Researchers have created brain growth charts that cover the human lifespan by aggregating more than 120,000 scans.Credit: Zephyr/SPL

When neuroscientist Jakob Seidlitz took his 15-month-old son to the paediatrician for a check-up last week, he left feeling unsatisfied. There wasn’t anything wrong with his son — the youngster seemed to be developing at a typical pace, according to the height and weight charts the physician used. What Seidlitz felt was missing was an equivalent metric to gauge how his son’s brain was growing. “It is shocking how little biological information doctors have about this critical organ,” says Seidlitz, who is based at the University of Pennsylvania in Philadelphia.

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Particle’s surprise mass threatens to upend the standard model

Data from an old experiment finds that the mass of the W boson is higher than theory predicts, hinting at future breakthroughs.

Davide Castelvecchi and Elizabeth Gibney

Nature | April 07, 2022

The Tevatron particle collider at Fermilab in Batavia, Illinois, was once the world’s most powerful accelerator.Credit: Granger/Alamy

From its resting place outside Chicago, Illinois, a long-defunct experiment is threatening to throw the field of elementary particles off balance. Physicists have toiled for ten years to squeeze a crucial new measurement out of the experiment’s old data, and the results are now in. The team has found that the W boson — a fundamental particle that carries the weak nuclear force — is significantly heavier than theory predicts.

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Stars may form 10 times faster than thought

Weak magnetic fields detected by China’s FAST telescope could upend theory of star formation

Ling Xin

SCIENCE | January 05, 2022

Herschel’s view of the Taurus Molecular Cloud
Dust in the Taurus Molecular Cloud, seen as pink hues in far-infrared light, traces dense regions of gas where stars form. A study of one of the cloud’s stellar embryos suggests the process is fast.ESA/HERSCHEL/NASA/JPL-CALTECH; R. HURT/JPL-CALTECH/CC-BY-SA

Astronomers have long thought it takes millions of years for the seeds of stars like the Sun to come together. Clouds of mostly hydrogen gas coalesce under gravity into prestellar cores dense enough to collapse and spark nuclear fusion, while magnetic forces hold matter in place and slow down the process. But observations using the world’s largest radio telescope are casting doubt on this long gestational period. Researchers have zoomed in on a prestellar core in a giant gas cloud—a nursery for hundreds of baby stars—and found the tiny embryo may be forming 10 times faster than thought, thanks to weak magnetic fields.

“If this is proven to be the case in other gas clouds, it will be revolutionary for the star formation community,” says Paola Caselli from the Max Planck Institute for Extraterrestrial Physics, who was not involved with the research.

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Want research integrity? Stop the blame game

Helping every scientist to improve is more effective than ferreting out a few frauds.

Malcolm Macleod

Nature | November 24, 2021

Most scientists reading this probably assume that their research-integrity office has nothing to do with them. It deals with people who cheat, right? Well, it’s not that simple: cheaters are relatively rare, but plenty of people produce imperfect, imprecise or uninterpretable results. If the quality of every scientist’s work could be made just a little better, then the aggregate impact on research integrity would be enormous.

How institutions can encourage broad, incremental improvements is what I have been working to figure out. Two things are needed: a collective shift in mindset, and a move towards appropriate measurement.

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Scammers impersonate guest editors to get sham papers published

Holly Else

Nature | November 08, 2021

Bookcase filled with publications
Scammers have impersonated researchers to gain access to reputable journals and publish special issues filled with nonsense papers.Credit: Getty

Hundreds of articles published in peer-reviewed journals are being retracted after scammers exploited the processes for publishing special issues to get poor-quality papers — sometimes consisting of complete gibberish — into established journals. In some cases, fraudsters posed as scientists and offered to guest-edit issues that they then filled with sham papers.

Elsevier is withdrawing 165 articles currently in press and plans to retract 300 more that have been published as part of 6 special issues in one of its journals, and Springer Nature is retracting 62 articles published in a special issue of one journal. The retractions come after the publishers each issued expressions of concern earlier this year, covering hundreds of articles.

Science-integrity experts expect that more investigations will come in the months ahead as other titles realize that they have been duped.

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DNA reveals surprise ancestry of mysterious Chinese mummies

Smriti Mallapaty

Nature | October 27, 2021

Aerial view of the Xiaohe cemetery surrounded by desert
Cemeteries in the Taklaman Desert, China, hold human remains up to 4,000 years old.Credit: Wenying Li, Xinjiang Institute of Cultural Relics and Archaeology

Since their discovery a century ago, hundreds of naturally preserved mummies found in China’s Tarim Basin have been a mystery to archaeologists. Some thought the Bronze Age remains were from migrants from thousands of kilometres to the west, who had brought farming practices to the area. But now, a genomic analysis suggests they were indigenous people who may have adopted agricultural methods from neighbouring groups.

As they report today in Nature1, researchers have traced the ancestry of these early Chinese farmers to Stone Age hunter-gatherers who lived in Asia some 9,000 years ago. They seem to have been genetically isolated, but despite this had learnt to raise livestock and grow grains in the same way as other groups.

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