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Nature, Published online: 13 December 2024; doi:10.1038/d41586-024-03969-z
A breathtaking total eclipse, courageous penguins, volcanic smoke rings and more.
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Author: chemistadmin
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The best science images of 2024 — <i>Nature’s</i> picks
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Inhere, Outthere
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Although the overhead fans hissed tirelessly, I swear I could feel it — the heat from outthere crawling through the cracks, threatening to do us all in. “Be my guest,” I dared the sliver of sun between the boarding bridge and the train. My hands itched as I rushed past business class, but when I snagged a seat, I found no rash on my palms. Not even a flush.
Of course not.
“Thank you for choosing …” the train speakers chased passengers to empty seats. If heat prickled their skin, their expressions did not betray it, although half the railcar hid behind masks. I made a game of guessing which dangers they sought to parry with polypropylene. For my part, the stench of gas — motor and human — had me reaching for my respirator.
Instead, I pulled up my hood.
“This seat taken?”
I turned to the stranger — you — with a flat frown. Coach wasn’t a place for courtesy. “Clearly it’s not.”
You grinned. “Gorge.”
As if to emphasize my incredulity, the speakers announced: “If you cannot find a seat, please wait for the next train.”
While I skimmed my e-book, you and your silver curls settled into the seat across. The black shimmer across your lids sharpened your eyes from curious to knowing. I couldn’t resign myself to your distraction so I searched my backpack for my pills.
Read more science fiction from Nature Futures
You smirked like we shared a secret.
“They’re authorized.”
“I’m sure.” When I didn’t respond to your teasing tone, you added, “Whatever it takes to reach tomorrow, right?”
“Tickets!” The conductor emerged, eyes tired, and squinted at your ID. “Damn.”
You laughed. “I know right!”
My own name inspired a similar sigh, but the speakers cut off the conductor’s wisecrack: “Thank you for choosing …”
“So wanna guess what name my parents cursed me with? I’ll give you a hint: celestial.”
My own snort surprised me. “That’d apply to me too.” I quickly added, “But I’m not one to talk to strangers.”
“Wouldn’t be strangers if we knew each other’s names.”
The hum of the train’s departure stole your attention and my medication mine. I turned up my phone’s brightness, determined to make it to the next page.
“Gorgeous,” you expanded your first abbreviation. My eyes darted up to clarify what, exactly, you were referencing. Not me — the view. Fields of sunflowers in perfect bloom.
“Almost too good to be true,” I muttered at the rows of golden-yellow.
Your gaze turned fond as if my cynicism was charming. “Is it so bad that I don’t want to see the real thing? There’s nothing we can do so I’d rather … pretend.”
“Pretend,” I repeated.
“That sounds horrible, doesn’t it?”
“No,” I said quietly. “Sounds like you’re trying to reach tomorrow.”
When you leaned forwards, I tightened my grip on my backpack — but you only pushed my hood away. “We’re safe inhere.”
Keystrokes and slow conversation filled our silence, and I wiggled on my sticky seat, trying to fold my long legs. You caught my ankles and stretched me into your space, then curled into a ball to sleep.
I managed a dozen pages and a dozen glances in your direction before the train made its first stop. “We’re having some technical issues, please remain seated.”
Five pages. Behind us, two teenagers flirted in low tones. I wondered if they thought the same of us. Ten pages. “Thank you for choosing …” Twenty pages. “We apologize for this delay. Feel free to get a ticket for the next train.” An elderly passenger scoffed, launching into a rant, while I pulled up the ticket prices on my phone.
You woke up with a pout. “What’s happening?”
“Delays. We can get on the next train though.”
“Are you?”
I sighed. “I can’t afford to.”
Five pages. An old couple told their love story to a chatty businessman. I caught your eye, by accident, and our frustrations softened. “That’s sweet.”
“Mm.”
Ten pages. Some left, many stayed. You sat awake, watching me. “Did you know that today used to be a holiday?” you made polite conversation. Only I wasn’t polite. “They called it May Day …” I worked hard not to listen.
Twenty pages. The conductor walked through the aisles, fielding questions and complaints. Every page or so, the speakers crackled, until at last: “We thank you for your patience, the journey will resume shortly.”
My mouth twisted up. The faces in the railcar were bewildered, sharing smiles of relief and irritation. You gifted me a wink, and god help me, my cheeks itched for it. This time, I didn’t blame the flush on delusions of heat.
“Aurora.”
“W — what?” I stammered.
“Your name, I’m trying to guess.”
I got one page in before you tried again. By attempt seven, the train began to slow, metal groaning beneath us. “Come on, it’s not Luna? You look like a Luna —”
The windows flickered, and all at once, sunflower fields gave way to truth. You hushed at the sight of outthere — a scorched wasteland of brittle weeds. The scattered carrion were more bones than flesh, and although the horizon blurred from heat, I could swear three figures stumbled across the ruins.
“Oh.” The breath punched out of you like a hiss. Or was that the heat at last crawling inhere? If the engine and displays had malfunctioned, could other systems in the train have failed? My hand hovered over the edges of the window as if I might wave to the three wanderers, until something — you — snatched it away.
You sat back in your seat with a squint, forcing yourself to bear witness.
“Hecate,” I whispered my name, desperate to pretend again.
But it only made the hiss louder.
“I’m Eos.”
Neither one of us knew what else to say. And when tears streaked through your black shimmer, all I could do was swipe my screen to the next page.
“Thank you for choosing …”
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How Elon Musk’s partnership with Trump could shape science in the US — and beyond
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Billionaire and entrepreneur Elon Musk (left) has become a confidante for US president-elect Donald Trump (right).Credit: Brandon Bell/Getty
Billionaire Elon Musk earned his reputation as an innovator at the forefront of science and technology, revolutionizing electric vehicles and space travel. But in the past several months, he has emerged as a major political figure in the United States, pouring more than US$250 million into Republican Donald Trump’s presidential campaign and using his social-media platform X (formerly Twitter) to question vaccine safety and climate science.
What Trump’s election win could mean for AI, climate and health
Now the entrepreneur is joining forces with president-elect Trump on a mission to downsize the US government — including potentially slashing the budgets and workforces of science agencies, which Musk’s companies Tesla and SpaceX relied on for government contracts to grow and thrive. It has left many in the research community raising questions about his political influence and what it means for science in the United States and beyond.
Although details about the US advisory body that Musk will help to lead, named the Department of Government Efficiency (DOGE), are scant, the billionaire, along with his co-chair, biotech entrepreneur Vivek Ramaswamy, laid out some of their intentions in a guest editorial in the Wall Street Journal last month. “Unelected bureaucrats” — a category that includes tens of thousands of scientists and other specialists — represent an “existential threat to our republic” owing to the unnecessary regulations on industry that they have helped to implement, the duo wrote. The pair then promised “mass headcount reductions across the federal bureaucracy”.
Musk has not responded to repeated requests for comment from Nature.
DOGE will undoubtedly face headwinds in achieving its cuts, policy observers who spoke to Nature say. Few, however, doubt that Musk will have far-reaching influence on science in the United States and beyond.
Shrinking the government
Conflicts of interest abound for Musk as a government adviser. The world’s richest man, Musk heads companies rooted in science, including private aerospace firm SpaceX, electric-vehicle company Tesla and brain-implant firm Neuralink. He has complained that US innovation is being held back by a “mountain of choking regulations” — government rules on everything from labour practices to data privacy that have repeatedly ensnared his own companies. In February 2022, for instance, Tesla agreed to pay a $275,000 fine after inspectors at the US Environmental Protection Agency (EPA) found that one of its manufacturing plants in Fremont, California, violated air-pollution regulations.
Musk’s deregulatory vision aligns with that of president-elect Trump. For instance, many expect Trump to roll back or weaken rules designed to curb pollution, protect public health and limit climate change when he takes office, much as he did during his first term in 2017–21. Whether government regulation actually hinders economic and technological innovation is a complex question, however.
Musk (left) transports his son as he and biotech entrepreneur Vivek Ramaswamy (right) visit Capitol Hill to meet with members of the US Congress on 5 December.Credit: Benoit Tessier/Reuters
Some research supports the idea that it can discourage growth or make it harder for big firms to acquire too much power by snapping up technology from start-up firms1,2. Many venture capitalists in places such as Silicon Valley, California, have focused on the latter restriction, and hope that the incoming Trump administration will relax rules governing mergers and acquisitions.
There are areas in which streamlining regulations makes sense, says Robert Atkinson, an economist and president of the Information Technology and Innovation Foundation in Washington DC. Environmental regulations, for instance, might protect public health by requiring firms to study the environmental impacts of their activities and limiting pollution, but they can also slow deployment of crucial clean-energy projects and infrastructure.
The real question lies in how regulations are crafted, says Scott Stern, an economist at the Massachusetts Institute of Technology in Cambridge. “Clear and stable regulation arguably provides the right incentives for innovation,” he says. For instance, clear rules governing drug development protect both public health and intellectual property, fostering private investment.
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US and China sign new science pact — but with severe restrictions
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US President Joe Biden (left) shakes hands with China’s President Xi Jinping (right) at an economic summit in November.Credit: Leah Millis/AFP via Getty
The United States and China have signed a brand-new, five-year agreement that dictates how the nations will cooperate on science and technology research. The pact is narrower in scope than its predecessor, covering only collaboration on basic science projects between departments and agencies of the two governments and excluding work on ‘critical and emerging technologies’ potentially important to national security, such as artificial intelligence and semiconductors. Unlike its predecessor, the pact does not include any information about collaboration among Chinese and US universities and private companies.
Why the US border remains ‘a place of terror’ for Chinese researchers
Experts in US–China relations welcome the agreement, saying that it will enable scientists to pursue projects with confidence.
“I am relieved to see this pact renewal,” says Duan Yibing, a science-policy researcher at the Chinese Academy of Sciences in Beijing, who hopes the pact will do what it’s designed to: promote collaboration in basic research between the two countries.
“It appears they scrubbed everything and started from scratch,” says Caroline Wagner, a specialist in science, technology and international affairs at The Ohio State University in Columbus. The narrow focus “seems appropriate” given China’s new status as a scientific and economic power. “The United States has recognized its relationship with China is now more symmetrical” than when the original agreement was signed 45 years ago, she says.
The agreement, “demonstrates a pragmatic, if constrained, approach to maintaining scientific collaboration amid geopolitical rivalry”, says Marina Zhang, an innovation researcher who focuses on China at the University of Technology Sydney in Australia.
A modernized agreement
The original pact was forged in 1979 to thaw diplomatic relations between China and the United States. It is normally renewed every five years, but it expired on 27 August last year amid rising tensions. Although the two nations recognized that new terms were needed in the agreement, they were unable to finalize the details before the deadline. Instead, they extended the old pact and kept negotiating.
US and China inch towards renewing science-cooperation pact — despite tensions
Researchers and other specialists warned that without the agreement, which is symbolic and doesn’t provide any funding, research cooperation and programmes between the two governments could flounder.
A US Department of State official said at a briefing on 12 December that the government recognized that failure to have an agreement would have a chilling effect on areas of science and technology that are important to the United States. The new agreement is “modernized, with built-in protections”, the official said.
The state department will now vet all research projects to ensure that they don’t pose national security concerns before they are approved. Proposals will also be reviewed by other US agencies led by the White House.
Aside from specifying that critical and emerging technologies are off the table for collaboration, the pact does not further limit which scientific areas are fair game. But a US state department official suggested permissible projects might include research on the weather, oceanography and geology, as well as collecting influenza and air-quality data.
China Initiative’s shadow looms large for US scientists
The revamped pact addresses concerns from the United States that China did not always meet its obligation to share data under the previous agreement. The United States has been frustrated, for instance, that China has not been more transparent about data collected by a virology laboratory in Wuhan, where the first COVID-19 cases were detected. Some think that a virus could have leaked from that lab to trigger the pandemic.
The agreement now includes wording that commits both the United States and China to sharing data, and being open and transparent. It also lays out a dispute-resolution mechanism by which both nations can iron out difficulties encountered in projects. If either side does not uphold its commitments, a termination clause allows the nations to end the agreement.
Many of the concerns about the old pact came from the United States, given China’s rise in power. So in these negotiations, China has been “the passive side”, Duan says.
An uncertain future
Because of the timing of the new pact’s signing, one uncertainty hanging over it is whether the incoming administration of president-elect Donald Trump, who will take office in about a month, will uphold it. Researchers who spoke to Nature say they don’t expect the Trump administration to declare the agreement weak and reverse it, given that it already represents a compromise. Also, the agreement was last renewed in 2018 during Trump’s first presidency, Duan points out. Still, he adds, “we have to see what he will do”.
Denis Simon, a non-resident fellow at the Quincy Institute for Responsible Statecraft, a foreign-policy think tank in Washington DC, says that the new agreement provides “clear guardrails and a path to negotiate disputes”.
Wagner adds that, because they have been excluded from the agreement, universities and private companies will need additional guidance from the two governments on the kinds of cooperation permitted.
Overall, “it’s good news we still have an agreement”, Simon says. “It has been modified to reflect US concerns, but it’s better than no agreement.”
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it has its very own immune system
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Skin can generate antibodies, independent of the rest of the immune system.Credit: kazuma seki/Getty
The skin — once thought to be a mainly passive barrier — can produce its own antibodies that fight off infections, a pair of studies reports in Nature this week1,2. The findings could pave the way for the development of needle-free vaccines that can be applied to the skin.
Although scientists have previously seen immune responses in the skin during infections, finding similar reactions in healthy skin is “a surprise”, says Daniel Kaplan, a dermatologist and immunologist at the University of Pittsburgh in Pennsylvania. “The idea of a semi-autonomous immune system in a peripheral tissue is very exciting,” he says.
Dual role
The immune system has to fight off harmful pathogens without attacking the helpful microorganisms that inhabit the body. Previous research showed3 that the skin of adult mice that had been raised without microbes could be colonized by Staphylococcus epidermidis, a common and harmless bacterium found on human skin. This long-term colonization triggered the production of specific immune cells, called T cells, which helped to strengthen local immunity.
“The next and maybe main chapter in this saga is that the response to this ubiquitous skin colonist is much more potent than we had realized,” says Michael Fischbach, a microbiologist at Stanford University in California, who co-authored both of the latest studies.
“When the immune system sees a friendly bacterium, you would think that it would just give a friendly wave and walk in the other direction, but that’s not at all what happens,” he says.
In experiments with mice, Fischbach and his colleagues discovered that S. epidermidis triggers the activation of B cells, the immune cells necessary to produce antibodies1. The skin then made antibodies against S. epidermidis; these persisted for at least 200 days and could form without previous exposure to other microbes.
The skin was able to generate this immune response even when lymph nodes — the immune hubs that help to activate immune cells — were disabled. The presence of S. epidermidis also induced the formation of specialized immune structures in the skin that attract T and B cells, boosting the production of antibodies.
Immune memory
Vaccines work by teaching the immune system — which includes T and B cells, along with antibodies — to recognize and remember a pathogen, so the body can respond quickly if exposed again.
Building on this idea, Fischbach and his team explored whether they could redirect the immune response triggered by the harmless S. epidermidis to target pathogens, to develop a new type of vaccine.
In a second study2, the researchers showed that S. epidermidis triggers an antibody response resembling that seen in conventional vaccines.
By modifying S. epidermidis to display foreign proteins — such as part of the tetanus toxin — on its surface, the researchers were able to induce immune responses in the mice’s bloodstream and in mucous membranes such as the lining of the nose. These responses protected the animals when they were given a lethal dose of the toxin.
Mucosal vaccines
Fischbach’s work is part of a growing interest in developing vaccines that induce antibodies in mucosal areas. This type of protection could help to stop respiratory or other infections before they start and reduce the spread of disease.
Another advantage over conventional vaccines is that engineered S. epidermidis could be added to a cream and simply applied to the skin. Such a vaccine, Fischbach says, would be cheap to produce and easy to distribute. Furthermore, it would not have to be administered by health-care worker, making it especially useful in under-served regions of the world.
The idea of using the immune response from S. epidermidis in the skin to develop therapies “is really out there”, says Thomas Kupper, a skin immunologist at Harvard Medical School in Boston, Massachusetts. “It is a super-creative application of these findings.”
But Kupper adds that it’s still unclear whether the skin’s response to S. epidermidis is as strong in people as it is in mice. Fischbach notes that early data suggest healthy people have high levels of antibodies against S. epidermidis. But before this approach can be used in people, it must first be proved safe and effective in non-human primates and in humans, following the usual process for developing medicines, he says. “If this is going to be deployed in the real world, we have to show that it works.”
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Fasting can reduce weight — but also hair growth
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Human hairs sprout from follicles, which contain stem cells that are sensitive to dietary changes (artificially coloured).Credit: Dr Keith Wheeler/SPL
A popular weight-loss regimen stunts hair growth, data collected from mice and humans suggest1. The study’s findings show that intermittent fasting, which involves short bouts of food deprivation, triggers a stress response that can inhibit or even kill hair follicle stem cells, which give rise to hair.
The results, published in today in Cell, suggest that although short-term fasting can provide health benefits, such as increased lifespan in mice, not all tissue and cell types benefit.
“I was shocked to hear these results,” says Ömer Yilmaz, a stem-cell biologist at the Massachusetts Institute of Technology in Cambridge who was not involved in the study. “We’ve come to expect that fasting is going to be beneficial for most, if not all cell types and good for stem cells. This is the inverse of what we expected, and the finding seems to hold true in humans.”
Deliberate deprivation
During the past decade, intermittent fasting has become one of the most popular dieting regimens; by one count, about 12% of adults in the United States practised it in 2023. One of the most common forms is time-restricted eating, which involves eating only within a limited time frame each day.
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First sighting of ‘neutrino fog’ sparks excitement – but is it bad news for dark matter?
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Most neutrinos that stream through Earth are produced by fusion reactions in the Sun.Credit: NASA/Goddard/SDO
Physicists in Italy and China have for the first time observed glimmers of the ‘neutrino fog’, signals from neutrinos that mimic those expected to be produced by dark matter.
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Wnt protein hitches a ride on exosomes
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Researchers from the Ottawa HospitalResearch Institute and the University of Ottawa in Canada, along with researchers from the Centre for Genomic Regulation at the Barcelona Institute for Science and Technology and the Center for Cooperative Research in Biosciences in Spain, have found the mechanism for how a member of the Wnt protein family manages to hitch a ride on cellular exosomes. The new work was published in Science Advances (2024, DOI: 10.1126/sciadv.ado5914).
Wnt proteins are important signalers for a wide range of processes, including regeneration after an injury and proliferation of stem cells. But because they are hydrophobic and insoluble, they don’t travel very far on their own. Despite this, long-range, paracrine Wnt signaling has been observed, and one explanation is that they stick to the outside of cell packages called exosomes. These exosomes are pouches that pinch off from the cell membrane and contain proteins and RNA. Despite observing this signaling, scientists weren’t sure how the Wnt proteins were able to stick to the exosomes before traveling long distances.
One of these Wnt proteins, Wnt7a, is upregulated after skeletal muscle injury, and intramuscular injections of Wnt7a into mouse models of Duchenne muscular dystrophy can slow the progression of the disease. Wnt7a’s insolubility makes it problematic as a possible therapeutic agent, but if it can attach to exosomes, it may be able to get where it needs to go.
The researchers found that Wnt7a is indeed able toattach to exosomes—and that it has a designated amino acid sequence for this very purpose. Wnt7a contains a signal sequence of 18 amino acids that binds to two coatomers, COPA and COPB2, that are present on the exosomes of muscle cells. Attached to the exosome, Wnt7a is transported to the exosome’s destination. When the researchers transferred this sequence to an unrelated peptide from a bacterial enzyme, they found that the peptide was able to stick to the exosomes as well.
Julia Gross, a professor of biochemistry at the Health and Medical University Potsdam who was not involved with the research, says the paper is thorough in showing that this domain exists, but the larger journey of Wnt7a is missing. While the biochemical evidence supports that this domain allows Wnt7a to stick to the exosome, it’s unclear how Wnt7a is trafficked to the outside of the exosome after it is translated, and if this peptide is necessary to travel to the exosome, not just stick to it.
Michael Rudnicki, one of the paper’s lead authors, says that this advance could accelerate developing Wnt7a and exosomes as a possible therapeutic, though much more work needs to be done.
“One can target, potentially, any protein to the surface of exosomes, and this is important for a therapeutic application and for targeting those exosomes to particular cell types or tissues,” he says..
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EPA seeks to protect workers from carbon tetrachloride
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The US Environmental Protection Agency has finalized a rule that allows current uses of the toxic solvent carbon tetrachloride to continue, as long as manufacturers meet new worker safety requirements—including a new inhalation exposure limit—within 3 years. The rule, released Dec. 11, bans uses of the chemical that have already been phased out.
Carbon tetrachloride is used primarily as a raw material to make other chemicals. Manufacturers claim that it is a critical feedstock for making refrigerants, aerosol propellants, foam-blowing agents, vinyl chloride, and a handful of other products.
The chlorinated solvent can cause liver cancer, as well as brain and adrenal gland tumors, according to the EPA. The US Consumer Product Safety Commission banned the use of carbon tetrachloride in consumer products in 1970. Most industrial uses, with the exception of chemical manufacturing, were phased out decades ago.
The EPA justifies allowing the chemical’s continued use, noting in a press release that it is essential for producing hydrofluoroolefin refrigerants, which are replacements for climate-damaging hydrofluorocarbons.
“With this action, we’re ensuring that the chemicals we need to power our economy are used safely,” Michal Freedhoff, assistant administrator for the EPA’s Office of Chemical Safety and Pollution Prevention, says in the release. “This rule puts necessary protections in place for workers, while also ensuring that important uses of this chemical can continue safely without unreasonable risk.”
Environmental groups say the rule will leave communities surrounding chemical facilities unprotected from unsafe levels of carbon tetrachloride in the air. In comments submitted to the EPA last year in response to the proposed rule, 14 groups urged the agency to eliminate all uses of carbon tetrachloride and promote safer alternatives.
The American Chemistry Council (ACC), which represents chemical manufacturers, questions the feasibility of the new worker inhalation limit. In comments about the proposed rule, the industry group pointed out that the EPA’s occupational exposure limit is much lower than the one set by the US Occupational Safety and Health Administration, the European Chemicals Agency, and dozens of other agencies around the globe. Nonetheless, the EPA finalized a strict limit of 0.03 ppm (the average exposure during an 8 h work shift) in its rule. OSHA’s permissible limit is 10 ppm.
Carbon tetrachloride is one of the first 10 chemicals the EPA evaluated under the Toxic Substances Control Act after Congress updated the law in 2016. The agency found unreasonable risks to human health from all 10 chemicals, but it has finalized rules to manage the risks for only 5 of them. In addition to the rule for carbon tetrachloride, the EPA finalized rules for 2 other solvents—trichloroethylene and perchloroethylene—this week. The agency finalized rules for chrysotile asbestos and methylene chloride earlier this year.
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BASF Opens Catalyst Development and Processing Center in Ludwigshafen
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Today, BASF officially opened its new Catalyst Development and Solids Processing Center in Ludwigshafen, Germany, inviting colleagues and members of the press to visit the new building. The new research facility, with its cutting-edge process equipment, will serve as a hub where the company conducts more focused and rapid development, testing, and optimization of innovative catalyst and process technologies on a pilot plant scale. The Center will also be of central importance for the development of new solids processing technologies. BASF develops catalyst and process technologies for its customers worldwide, it also uses a minor part of them in its own manufacturing plants.
BASF constructed the new Center within three years to replace an older building. The new building has state-of-the-art safety features, such as separate black and white zones with locks that remain sealed off from one another to prevent the spread of heavy metal dust, and it is equipped with numerous new technologies for R&D activities. In total, the company invested a high double-digit million-euro figure in the new Catalyst Development and Solids Processing Center. The approximately 200 mid-scale pieces of equipment will be managed by 25 permanent staff members, with additional personnel from other departments joining as needed for specific research projects.More than 80% of all chemical products come into contact with a catalyst at least once during their production. In industry, heterogeneous catalysts typically appear as metal-based solid materials, often in the form of pellets, powders, or granular substances. The solid catalyst provides a surface for reactants to adsorb, react, and then desorb as products. Modern equipment from the old building is being moved to the new facility, including several unit operations, such as equipment for producing new 3D-printed catalysts. 3D printing allows for the creation of porous materials to increase surface area. This technology is also scalable, enabling both development of prototypes for new catalysts and large-scale production.
The picture above shows equipment for drying solid materials. In spray drying, used to produce fine powders, the starting material is sprayed via a nozzle or atomizer into a hot gas stream. The particles are dried in the hot gas (e.g., air or nitrogen) in a very short time, either by being sprayed from top to bottom or from bottom upwards to allow more time for drying.
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