Company Allvar working with NASA on NTE space telescope optics; other applications are possible.
A new material that shrinks when it is heated and expands when it is cooled could help enable the ultra-stable space telescopes that future NASA missions require to search for habitable worlds; planets beyond our solar system (exoplanets) that could support life. Over the past two decades, scientists have developed ways to detect atmospheres on exoplanets by closely observing stars through advanced telescopes. As light passes through a planet’s atmosphere or is reflected or emitted from a planet’s surface, telescopes can measure the intensity and spectra of the light, and can detect various shifts in the light caused by gases in the planetary atmosphere.
To successfully detect habitable exoplanets, NASA’s future Habitable Worlds Observatory (HWO) will need a contrast ratio of one to one billion. This in turn will require a telescope that is 1,000 times more stable than state-of-the-art space-based observatories like NASA’s James Webb Space Telescope and its forthcoming Nancy Grace Roman Space Telescope. New sensors, system architectures, and materials must be integrated and work in concert for future mission success.
A team from Allvar Alloys, College Station, TX, and Syracuse, NY, is collaborating with NASA’s Marshall Space Flight Center and NASA’s Jet Propulsion Laboratory to demonstrate how integration of a new material with “unique negative thermal expansion characteristics” can help enable ultra-stable telescope structures.
The materials currently used for telescope mirrors and struts have drastically improved the dimensional stability of the great observatories like Webb and Roman, but as indicated in the Decadal Survey on Astronomy and Astrophysics 2020 developed by the National Academies of Sciences, Engineering, and Medicine, they still fall short of the 10 picometer level stability over several hours that will be required for the HWO.
Funding from NASA and other sources has enabled this material to transition from the laboratory to the commercial scale. Allvar received NASA Small Business Innovative Research funding to scale and integrate a new alloy material into telescope structure demonstrations for potential use on future NASA missions like the Habitable Worlds Observatory.
This alloy shrinks when heated and expands when cooled – a property known as negative thermal expansion. For example, Allvar’s Alloy 30 exhibits a -30 ppm/°C coefficient of thermal expansion at room temperature. This means that a 1-meter long piece of this NTE alloy will shrink 0.003 mm for every 1 °C increase in temperature. In contrast, aluminum expands at +23 ppm/°C.
Because it shrinks when other materials expand, Allvar Alloy 30 can be used to strategically compensate for the expansion and contraction of other materials. The alloy’s unique NTE property and lack of moisture expansion could enable optic designers to address the stability needs of future telescope structures.
Thermal stability ‘improved up to 200 times’
Calculations have indicated that integrating Alloy 30 into certain telescope designs could improve thermal stability up to 200 times compared to only using traditional materials like aluminum, titanium, carbon fiber reinforced polymers, and the nickel–iron alloy, Invar.
To demonstrate that negative thermal expansion alloys can enable ultra-stable structures, the Allvar team developed a hexapod structure to separate two mirrors made of a commercially-available glass ceramic material with ultra-low thermal expansion properties. Invar was bonded to the mirrors and flexures made of Ti6Al4V—a titanium alloy commonly used in aerospace applications—were attached to the Invar.
To compensate for the positive CTEs of the Invar and Ti6Al4V components, an NTE Allvar Alloy 30 tube was used between the Ti6Al4V flexures to create the struts separating the two mirrors. The natural positive thermal expansion of the Invar and Ti6Al4V components is offset by the negative thermal expansion of the NTE alloy struts, resulting in a structure with an effective zero thermal expansion.
The stability of the structure was evaluated at the University of Florida Institute for High Energy Physics and Astrophysics. The hexapod structure exhibited stability well below the 100 pm/√Hz target and achieved 11 pm/√Hz. This first iteration is close to the 10 pm stability required for the HWO. A paper and presentation made at the August 2021 Society of Photo-Optical Instrumentation Engineers conference provides details about this analysis.
Furthermore, a series of tests run by NASA Marshall showed that the ultra-stable struts were able to achieve a near-zero thermal expansion that matched the mirrors in the above analysis. This result translates into less than a 5 nm root mean square change in the mirror’s shape across a 28K temperature change.
Beyond ultra-stable structures, the NTE alloy technology has enabled enhanced passive thermal switch performance and has been used to remove the detrimental effects of temperature changes on bolted joints and infrared optics. These applications could impact technologies used in other NASA missions. For example, these new alloys have been integrated into the cryogenic sub-assembly of Roman’s coronagraph technology demonstration.
It’s easy to think, given the current geopolitical state of the world, that we’re living through an especially terrible time. Add to that the possibility that Earth may be undergoing its sixth mass extinction and it’s perhaps justified to conclude that the 21st century is the worst time period ever.
While this may be the case by some definitions, there’s no escaping the fact that we, as a species, have it better than our ancestors and those that came before them ever did. For the majority of Earth’s history, life has simply been a matter of survival. Let’s take a look at some times when staying alive was particularly difficult…
10 terrible times to be alive
The time the ocean lost almost all its oxygen
The Middle Cretaceous may have been a particularly prosperous time for life on land, but under the waves a geochemical storm was slowly brewing – one that would eventually rob the oceans of oxygen and cause the extinction of more than 25% of marine invertebrates, as well as one of the most iconic marine reptiles of the Mesozoic Era, ichthyosaurs.
This calamitous event is known as the Cenomanian-Turonian boundary event and it’s widely considered to be the most recent, truly global oceanic anoxia event in Earth’s history. It happened roughly 94 million years ago following the eruption of a series of underwater volcanoes in the newly formed Atlantic Ocean.
These eruptions released nearly 4 million cubic kilometres of lava (enough to fill the Mediterranean Sea) and enough CO₂ to raise global temperatures by more than 5°C. At the equator during this time, water temperatures exceeded 42°C, which is warmer than those typically experienced in a hot tub! Even water temperatures at the poles were a balmy 20°C.
This period also witnessed massive plankton blooms – caused by an increase in dissolved nutrients as a result of increased rock weathering. When this plankton died it was eaten by bacteria, which consumed lots of dissolved oxygen from the water column.
For more than half-a-million-years, the deeper levels of the world’s oceans were devoid of oxygen, making them inhospitable to almost all forms of life.
The time a tsunami (may have) submerged part of Europe
Doggerland: Credit Caroline May
Not too long ago (around 10,000 years), a land bridge known as Doggerland connected the east coast of the UK to the Netherlands, northwest Germany, and the Danish peninsula of Jutland.
This lowland area was once inhabited by mammoths, cave lions, sabretooth tigers, and several other iconic ice age animals. It was also home to roaming bands of hunter gatherers, as evidenced by the discovery of several artifacts dredged up during trawling missions in the North Sea – the most famous being a 20cm-long harpoon carved from a deer’s antler.
For our ancestors, Doggerland provided some of the continent’s richest hunting grounds, not to mention a bountiful supply of freshwater. However, by 8,000 years ago it had completely disappeared beneath the waves.
What happened to Doggerland is controversial. Some claim it was suddenly submerged by a tsunami triggered by an underwater landslide just off the coast of Norway 8,200 years ago, while others think it was slowly consumed by rising sea levels.
In reality, it was likely a combination of both. A 2020 study put forward evidence to suggest that Doggerland had already reduced dramatically in size (as a result of rising sea levels) by the time the tsunami hit. Regardless, anyone who lived in Doggerland 8,200 years ago would have probably given everything they had to be anywhere else.
The time when insects were massive
If insects make your skin crawl, then the Carboniferous Period (359 to 299 million years ago) would probably be your idea of hell on Earth. This is a period often referred to as the ‘Age of Giant Insects’, and for good reason – during the Carboniferous, Earth was ruled by bugs many times bigger than any alive today.
The 2m-long, double-duvet sized Arthropleura was the largest of the Carboniferous’ giant bugs. It’s distantly related to today’s millipedes and like its living relatives it also subsisted on a diet of decaying plants and animals. There was also a dragonfly-like insect known as Meganeura that, with a 75cm-wide wingspan, was roughly the same size as a sparrowhawk.
It’s often said that bugs achieved gigantism during the Carboniferous as a result of increased levels of oxygen in the atmosphere, and while this may be true to some degree it’s more likely they grew so large in response to a lack of competition from vertebrates. At this time, vertebrates were still relatively small and largely confined to environments close to water.
As a group, vertebrates were dwarfed and outnumbered by bugs during the Carboniferous, but fast forward a few million years to the Permian Period (299 to 252 million years ago) and they soon emerged as the most dominant forms of life on land. The Permian was a period of great diversification for vertebrates. However, while it may have been evolutionary prosperous for some groups, it ended in disaster for others – but more on that later.
The time fungi towered over everything else
The first kind of life to really gain a foothold on land wasn’t plants, but fungi. The first fungi were relatively small, but they soon paved the way for giants such as Prototaxites. This tree-like organism lived roughly 400 million years ago and formed huge spires that measured up to 1m in diameter and reached heights of more than 8m.
It’s unclear exactly what Prototaxites was; it may have been a fungus, or it may belong to a long-lost group of lichens. Whatever its affinities, Prototaxites was by far the largest land-dwelling organism of its time and towered over everything that attempted to grow in its shadows.
Prototaxites, along with many other early types of fungi, are thought to have been saprotrophic. This is a process whereby fungi release digestive enzymes that break down organic matter, allowing them to extract nutrients from the material they’re growing on. These enzymes are so powerful that, over time, they can break down rock and form fertile soils. It’s this process that researchers think prepared Earth’s surface for the vascular plants that emerged during Prototaxites’ reign
So, why was this a particularly terrible time to be alive? Well, without large networks of plants producing oxygen, levels of it in the atmosphere were a lot lower than they are today. There was also very little to eat, especially if you weren’t a fan of mushrooms.
The time a pandemic lasted 18 million years
From the Early Oligocene (33 million years ago) to the Early Miocene (15 million years ago), an ancient virus known as ERV-Fc plagued dozens of different species of mammals, from dolphins to great apes. The inactive fragments of this virus still live on in many mammals today, including us, and it’s the study of these fragments that have allowed scientists to learn more about it.
ERV-Fc is what’s known as an endogenous retrovirus – a type of virus that infects cells and inserts itself into its host’s DNA. When this happens in reproductive cells, the viral sequence can be passed from parent to offspring. ERVs are very common in the genomes of vertebrates and are estimated to make up nearly 8% of our own genome.
A 2016 study revealed that ERV-Fc independently infected many different groups of mammals, rather than a single shared ancestor. This study also found evidence to suggest that the virus jumped species more than 20 times over the course of an 18-million-year-long pandemic that spread across all continents besides Australia and Antarctica.
It’s unclear exactly how deadly ERV-Fc was, but based on its structure it’s understood to be part of a group of viruses known as gammaretroviruses. Today, this group includes the murine leukemia virus (MuLV) in mice and feline leukemia virus in cats (FeLV), both of which are known to cause cancer.
The time when Earth was ruled by giants
The blue whale (Balaenoptera musculus) may be the largest animal to have ever lived, but on average animals alive today are a lot smaller than those that lived during parts of prehistory.
The Late Jurassic (162 to 143 million years ago) is a period that’s particularly renowned for its giants. It’s often referred to as the ‘Golden Age’ of not only dinosaurs, but pterosaurs and marine reptiles too – wherever you lived during the Late Jurassic, be it on land, in the sky, or in the oceans, a giant, hungry reptile was never too far away.
Some of the largest dinosaurs of the time lived in North America and are known from fossils uncovered from the world famous Morrison Formation. This expansive, dinosaur-bearing rock formation has yielded more than 10 different meat-eating theropods, all of them large enough to hunt human-sized animals.
The king amongst these theropods wasn’t T.rex (that particular species appeared in the Late Cretaceous around 70 million years later), rather Allosaurus – a smaller but arguably more belligerent predator that’s thought to have hunted in packs and been capable of bringing down giant, long-necked dinosaurs known as sauropods. These plant-eating sauropods would have been deadly too, crushing anything unlucky enough to get caught under their feet.
The Late Jurassic may have been a great time to be a giant, but for any animal smaller than a Volkswagen Beetle it would have been particularly terrible.
The time it rained for 2 million years
The Triassic (252 to 201 million years ago) is widely regarded as one of the hottest and driest periods in Earth’s history. However, during this 51-million-year-long period, there was a 2-million-year-long episode when it rained pretty much non-stop.
This is known as the Carnian Pluvial Episode (CPE) and it started roughly 234 million years ago. It’s evidenced by thick layers of river rocks, sediments from giant lakes, and evidence of coal swamps sandwiched in between layers of drier rocks more traditionally associated with the Triassic, such as red sandstones. These peculiar layers are signs of increased rainfall and they’re found all over the world, hinting at a global climate shift.
Some estimates suggest that rainfall quadrupled over this period and as much as 1,400mm of rain was dumped every year – that’s how much a temperate rainforest gets today, but this would have fallen across the entire supercontinent of Pangea!
This massive amount of rain had a profound impact on the animals that lived during the Middle Triassic, particularly the dinosaurs. In rocks dated to the start of the CPE, dinosaurs make up just 5% of the fossils of terrestrial vertebrates. In rocks dated to the end of this episode, they comprise more than 90%.
The dinosaurs’ distant relatives, the crocodile-line archosaurs, didn’t relish the rain quite as much, which is ironic considering the watery habitats their descendants live in today. They experienced huge losses at this time and never again reached the diversity they had during the Early Triassic.
The time an asteroid destroyed a dynasty overnight
Since the emergence of animals some 800 million years ago, Earth has witnessed five major mass extinctions – together these are known as the ‘Big Five’.
The event that wiped out the dinosaurs 66 million years ago wasn’t the most destructive of the five – that title goes to an event discussed later – but it is the one that wiped out entire families of animals and plants in a matter of days, rather than over the course of millennia.
This event, known as the K-Pg mass extinction, was caused by the impact of a giant, 15km-wide asteroid that made landfall in what is now the Yucatán Peninsula in Mexico. Based on fish bones found in the impact’s ejecta layer, it’s thought the impact may have taken place during spring.
The effects of the impact were catastrophic; any animals (or plants) standing within 1,500km at the time of the impact would have been instantly vaporised. Those standing further away weren’t exactly safe and would have arguably faced an even more painful death, being melted by firestorms, catapulted by hurricane-force winds, crushed by blazing debris, or simply suffocated by the poisonous air.
It’s estimated that the energy released during the impact was equivalent to 10 billion Hiroshima bombs.
There were some plucky animals that survived this ‘worst day ever’, including our mammalian ancestors, but when the fires finally burnt themselves out and the dust clouds settled, as many as 75% of species on Earth had disappeared.
The time when humans were prey
We may be firmly at the top of the food chain today, but for the majority of our existence we were prey for many larger, toothier predators.
While they’re not considered a member of our genus (Homo), australopithecines are often referred to as ‘humans’, or at least incredibly close relatives. Later undisputed human species include Homo erectus, Homo neanderthalensis, and – of course – Homo sapiens. These early humans lived alongside some of prehistory’s most terrifying animals, including sabretooth tigers, giant short-faced bears, and baby-eating eagles.
There’s lots of evidence to suggest that early humans were prey for such animals. The most famous example is the 2.8-million-year-old Taung Child – a fossilised skull of a young Australopithecus africanus that bears a puncture wound in each of its eye sockets. These wounds match those made by the talons of a crowned eagle, suggesting the child was killed and carried off by an airborne predator.
There’s gruesome evidence of our distant relatives being hunted by big cats too – the remains of a female Paranthropus robustus found in a cave in South Africa show signs of having been bitten and gnawed on by a leopard.
As humans got larger and, crucially, smarter, it’s likely that more and more predators stopped viewing them as prey. That said, we shouldn’t get too complacent; even today there are animals that, if hungry enough, will target humans, such as tigers, polar bears, and crocodiles.
The time nearly everything died
Known fittingly as the ‘Great Dying’, the End-Permian mass extinction is the third of Earth’s ‘Big Five’ and – in terms of how many species were wiped out as a result – the most destructive. This era-defining event almost ended life on Earth entirely and by some estimations may have consigned as many as 90% of species to extinction!
The impacts of this event were destructive on land, but they were truly cataclysmic in the oceans where entire ecosystems collapsed, never to be seen again. Some of the most diverse groups in preceding periods, such as eurypterids, trilobites, and blastoids, were completely eradicated during this event. Others lost more than 95% of their species (e.g. brachiopods, crinoids, and ammonites) and only narrowly made it through to the following period, the Triassic.
The ‘Great Dying’ is widely considered to have been caused by the eruption of a huge volcanic system that lay under what is now Siberia, Russia. This eruption released huge amounts of greenhouse gases into the atmosphere, which elevated global temperatures and acidified the planet’s oceans. This injection of greenhouse gases raised levels of CO₂ in the atmosphere from 400 ppm to 2,500 ppm. To put that into perspective, current CO₂ levels measure ~430 ppm.
The ‘Great Dying’ didn’t happen overnight like the extinction event that claimed the lives of the dinosaurs; instead it lasted for nearly 50,000 years and may have taken place in several distinct pulses. Staying alive during this time would have been particularly difficult, though it wasn’t impossible and our existence today is proof that some resilient animals made it through.
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For decades, scientists have been building synthetic versions of viruses, bacteria, and yeast, but now U.K. scientists are setting their sights on the human genome.
Building a synthetic genome would be much different than gene editing, which contains smaller edits to one’s own genome.
While a synthetic human genome could dramatically improve our ability to manage our health, it could also be a deadly weapon if used for nefarious purposes.
The ethical duality of scientific discovery is nothing new. The most dramatic example is, of course, splitting the atom, which delivered a promising new energy source as well as weapons of mass destruction. A more recent example—the internet—was an unprecedented way to access the sum total of human knowledge, and it also became an insidious vector of mass misinformation. Now scientists are embarking on a new scientific journey, one that could bring unimaginable benefits for human health while also providing the tools for immense destruction.
We’re going to synthesize the human genome.
Over the next five years, the Synthetic Human Genome Project (SynHG), funded by the world’s largest medical charity Wellcome Trust (which was also a partner of the Human Genome Project completed in 2003), will work with scientists from Cambridge, Kent, Manchester, Oxford, and Imperial College London to build the foundational tools necessary to rebuild the human genome from scratch. This is different than gene editing, which typically involves much smaller changes to an organism’s original DNA.
“With recent technological advances, the SynHG project is at the forefront of one of the most exciting areas of scientific research,” Wellcome’s Michael Dunn said in a press statement. “Through creating the necessary tools and methods to synthesize a human genome, we will answer questions about our health and disease that we cannot even anticipate yet, in turn transforming our understanding of life and wellbeing.”
In an interview with the BBC, Julian Sale, a member of the Molecular Biology in Cambridge who is part of the study, said that a synthetic human genome could improve the lives of humans as they age. This focus on healthspan—improving the quality of life for the years we do have—over lifespan is something medical professionals have been urging for years, and a synthetic human genome could address a wide variety of maladies that impact our quality of life in old age.
And then, there’s the other side of the scientific coin.
While a synthetic genome could help generate disease-resistant cells or repair damaged organs or the immune system in general, the technology could also be used as a highly efficient biological weapon if it fell into the wrong hands. That’s why SynHG will also develop social science programs that will examine the technology’s ethical, legal, and social implications.
“The genie is out of the bottle,” Edinburgh University genetic scientist Bill Earnshaw told BBC News. “We could have a set of restrictions now, but if an organization who has access to appropriate machinery decided to start synthesising anything, I don’t think we could stop them.”
When it comes to synthetic biology, the genie has actually been out of that proverbial bottle for a while now. In 2002, scientists in the U.S. first synthesized a viral genome, and since then, scientists have increased genomic complexity by synthesizing a bacterium in 2008 and a yeast organism in 2017. Of course, the human genome is leagues beyond these simple synthetic reconstructions, which is why the project scientists estimate that it could take decades to complete.
Hopefully that provides enough time for humanity to fully grapple with the implications of such a breakthrough and ensure that we don’t accidentally create yet another weapon of mass destruction.
The study, published in the Proceedings of the National Academy of Sciences (PNAS), marks a milestone in reproductive science, opening the door to potential future applications in fertility medicine and genetic research.
The team, led by Professor Yanchang Wei, achieved this result by injecting sperm from two male mice into an egg cell that had been stripped of its maternal DNA. Crucially, they applied a method known as epigenome editing, which reprograms gene activity without altering the DNA sequence itself.
“We attempted to improve the development of androgenetic embryos by restoring the epigenetic status of these ICRs [imprinting control regions],” the researchers wrote.
Out of 259 embryos implanted into surrogate female mice, only three pups were born, and two survived into adulthood. Despite the low 0.8% success rate, both surviving mice were able to reproduce normally, proving their fertility and general health.
“Our efforts enabled us to generate androgenetic mice that can develop to adulthood and are fertile, using the genetic materials derived from two sperm cells,” the scientists noted.
This research is based on overcoming genetic imprinting, a process in which chemical labels on DNA determine which genes are active in a given embryo. Normally, imprinting is balanced between maternal and paternal chromosomes, but this balance is disrupted when both sets of chromosomes come from the same sex, often leading to developmental failure.
While scientists managed to generate viable embryos from two female mice as early as 2004, replicating this process with two male mice had remained elusive due to the complexity of correcting paternal imprinting patterns. Wei’s team solved this by targeting and modifying seven key ICRs known to be essential for development.
Despite the promising results in mice, the road to human application remains long and uncertain. “Although the efficiency is low at present, this finding may be an important step toward achieving mammalian androgenesis,” the authors acknowledged. Experts also caution that the low success rate, ethical concerns, and regulatory restrictions make it unlikely that similar techniques will be applied to human embryos in the near future.
Earlier, it was reported that an American scientist achieved a significant breakthrough in understanding how axolotls – Mexican salamanders known for their remarkable regenerative abilities – are able to regrow limbs and organs.
Scientists at École Polytechnique Fédérale de Lausanne have developed a solution that prevents fusion reactors from overheating, Phys.org reported.
The breakthrough centers on a clever design called the X-point target radiator. This innovation adds a second magnetic control point to tokamak fusion reactors, creating a safety valve that sheds dangerous excess heat before it can damage the reactor walls.
Fusion reactors face a massive heat management problem. These doughnut-shaped devices, called tokamaks, use powerful magnetic fields to contain plasma heated to over 100 million degrees Celsius. When this superhot plasma touches the reactor walls, it can cause severe damage that shortens the reactor’s lifespan and hurts performance.
The Swiss research team discovered that adding a secondary X-point along the reactor’s heat exhaust channel creates localized radiation that pulls heat away from sensitive areas. Think of it like adding a second drain to prevent your bathtub from overflowing.
“Reducing divertor heat loads is a key challenge for future fusion power plants,” Kenneth Lee, first author of the paper, told Phys.org.
The EPFL team used its TCV tokamak’s unique magnetic shaping abilities to test this concept. Experiments showed the X-point target radiator stays stable across a range of operating conditions, making it much more reliable than previous heat management approaches.
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“We found that the X-point target radiator is highly stable and can be sustained over a wide range of operational conditions, potentially offering a much more reliable method for handling power exhaust in a fusion power plant,” Lee said.
Fusion energy could change how we power our world. Unlike coal and gas, fusion creates massive amounts of electricity without producing harmful gases or long-lived radioactive waste. A single fusion plant could power entire cities on fuel extracted from seawater.
The X-point target radiator makes fusion power plants more practical by solving the overheating problem that has plagued reactor designs. This means fusion plants could run longer and more efficiently, reducing electricity costs for everyone.
Commonwealth Fusion Systems and the Massachusetts Institute of Technology plan to include the X-point target design in their upcoming SPARC reactor, which looks to demonstrate commercial fusion power.
Diversifying our energy sources with fusion power would dramatically reduce air pollution from coal and gas plants. Cleaner air means fewer respiratory problems, heart disease cases, and premature deaths in communities near power plants.
Fusion power could slash electricity bills once the technology scales up. The fuel comes from abundant hydrogen isotopes found in seawater, making long-term operating costs extremely low.
Cities and companies investing in fusion power could reap major savings compared to volatile coal and gas prices. The stable costs of fusion electricity would help businesses plan budgets and keep energy affordable for residents.
The SPARC reactor incorporating this heat management technology is scheduled for testing in the coming years. If successful, commercial fusion plants using the X-point target radiator could begin operating in the 2030s.
The researchers will continue refining their approach with high-power experiments and simulations.
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A University of Illinois study found that certain charged nanoplastics can boost the virulence of foodborne pathogens like E. coli, making them harder to eliminate.
The bacteria exposed to nanoplastics developed biofilms, which shield them from antibiotics and sanitation methods.
A separate Boston University study found that microplastics enable bacteria to resist multiple antibiotics, raising concerns that regions with higher plastic pollution, such as low-income areas, may face increased risks of infection.
Microplastics are truly everywhere. As the World Economic Forum explained, these tiny plastic particles measuring 5 millimeters or less have been found across land, oceans, the air, and throughout our food chain. They’ve also been detected in human blood and in the brain. We still don’t know much about how they actually impact human health. However, a new study suggests that microplastics could have an unexpected effect: making foodborne illnesses even more dangerous than before.
In April, researchers from the University of Illinois Urbana-Champaign published their study findings in the Journal of Nanobiotechnology, examining how nanoplastics, which are a mere 1 micrometer wide or smaller, react when they come into contact with foodborne pathogens, specifically E. coli O157:H7, a particularly harmful strain that can cause serious illness in humans.
“Other studies have evaluated the interaction of nanoplastics and bacteria, but so far, ours is the first to look at the impacts of microplastics and nanoplastics on human pathogenic bacteria,” the study’s senior author, Pratik Banerjee, who is also an associate professor in the department of food science and human nutrition and an Illinois Extension Specialist, shared in a statement.
Using three types of polystyrene-based nanoplastics — one with a positive charge, one with a negative charge, and one with no charge at all — the team discovered that these nanoparticles can significantly influence how bacteria grow, survive, and even how dangerous they become. In particular, those exposed to a positive charge.
That’s because the positive charge caused a “bacteriostatic” effect, which slowed but did not stop the E. coli from growing. Instead, it adapted, resumed growth, and formed biofilms, which make bacteria harder to kill.
“Just as a stressed dog is more likely to bite, the stressed bacteria became more virulent, pumping out more Shiga-like toxin, the chemical that causes illness in humans,” Banerjee said.
The researcher noted that these biofilms form a “very robust bacterial structure and are hard to eradicate,” emphasizing that their goal was to observe what occurs “when this human pathogen, which is commonly transmitted via food, encounters these nanoplastics from the vantage point of a biofilm.”
Although the research doesn’t suggest that micro- and nanoplastics are the only cause of foodborne illness outbreaks, they point out that interactions like the ones they observed “lead to enhanced survival of pathogens with increased virulence traits.”
This isn’t the only study highlighting the effects of microplastics on bacteria. In March, researchers from Boston University published their findings in the journal Applied and Environmental Microbiology, which showed that bacteria exposed to microplastics could become resistant to “multiple types of antibiotics commonly used to treat infections.”
They also specifically studied how E. coli (this time using MG1655, a non-pathogenic laboratory strain) reacted to microplastics, and, as Neila Gross, a PhD candidate in materials science and engineering and the lead author of the study, shared, “The plastics provide a surface that the bacteria attach to and colonize.” On those surfaces, Gross and her team also found that they created that dangerous biofilm, which “supercharged the bacterial biofilms,” making it impossible for antibiotics to penetrate.
“We found that the biofilms on microplastics, compared to other surfaces like glass, are much stronger and thicker, like a house with a ton of insulation,” Gross added. “It was staggering to see.”
Furthermore, the BU team pointed out that while microplastics are everywhere, they are especially problematic in lower-income areas of the world that may lack the ability to control pollution flow.
“The fact that there are microplastics all around us, and even more so in impoverished places where sanitation may be limited, is a striking part of this observation,” Muhammad Zaman, a BU College of Engineering professor of biomedical engineering who studies antimicrobial resistance and refugee and migrant health, added. “There is certainly a concern that this could present a higher risk in communities that are disadvantaged, and only underscores the need for more vigilance and a deeper insight into [microplastic and bacterial] interactions.”
TWA 7 is blocked in this image by the black circle, while the planet glows in orange – credit, NASA, ESA, CSA, Anne-Marie Lagrange (CNRS, UGA), Mahdi Zamani (ESA / Webb)
Since its debut in 2021, the James Webb Space Telescope has dazzled viewers with its infrared images of galaxies, nebulae, stars, and even our own solar system’s planets.
Now, the most expensive telescope ever made has unveiled a new trick—a coronagraph, which allows it to block the light of a star and see what small objects are orbiting it. In this case, it performed the first direct photographing of an exoplanet in human history; probably.
The image found a faint source of infrared light in a disk of debris orbiting TWA 7, a red dwarf star around 111 light years from Earth. With the outstanding chance of the object being a background galaxy at more than 0%, the researchers can’t say for certain it’s a planet, but they suspect very much that it is—around the size of Saturn and sitting at a comfortable 120° Fahrenheit.
Though astronomers have detected well over 5,000 exoplanets so far, each one has been done through indirect methods, such as the “transit method.” The transit method sees an astronomer train a telescope on a star, and monitor for predictable drops in the level of light from the star that would indicate a planet orbiting it. The transit method can also work through measurements of gravity since passing planets’ gravitational fields can cause their host stars to “wobble.”
By contrast, the coronagraph will be much more straight forward, and TWA 7 b will likely be the first of many that the Webb telescope will discover.
One can think of the coronagraph as an on-demand eclipse service. The instrument positions a disk inside the lens of the imaging device to perfectly eliminate the star’s light from entering the sensor within a degree of micrometers. With the pollution of the star’s light gone, small things—in this case an exoplanet—can be seen.
RECENT WORK FROM JAMES WEBB
“Our observations reveal a strong candidate for a planet shaping the structure of the TWA 7 debris disk, and its position is exactly where we expected to find a planet of this mass,” Anne-Marie Lagrange, lead author of the study and an astrophysicist at the French National Center for Scientific Research, said in a statement released by NASA on the discovery.
The source is located in a gap in one of three dust rings that were discovered around TWA 7 by previous ground-based observations. The object’s brightness, color, distance from the star, and position within the ring are consistent with theoretical predictions for a young, cold, Saturn-mass planet that is expected to be sculpting the surrounding debris disk.
These visible rings or gaps are thought to be created by planets that have formed around the star, but such a planet has yet to be directly detected within a debris disk. If TWA 7 b is confirmed to be such, it would mark a major moment in astronomy.
SHARE This Great New Trick From Our Expensive Space Telescope…
A new study using images from the James Webb Space Telescope (JWST) has helped to answer a continuous question in astronomy.
Astronomers have been able to identify both thin and thick stellar disks in galaxies, extending far beyond our local universe, with some dating back 10 billion years
The research was led by an international team and recently published in the Monthly Notices of the Royal Astronomical Society. It analysed 111 edge-on galaxies captured by JWST. These galaxies were positioned in a way that allowed their vertical structure to be studied in detail, enabling scientists to see their internal layering like never before.
Two stellar disks, two histories
Many disk galaxies, including the Milky Way, are composed of two key components: a thick disk and a thin disk. The thick disk contains older, metal-poor stars, while the thin disk hosts younger, metal-rich stars. These distinct parts offer clues to the history of star formation and chemical enrichment in galaxies.
Until the launch of JWST in 2021, only nearby galaxies could be studied in this level of detail. Older telescopes lacked the resolution to observe the thin edges of distant galaxies. But JWST’s sharp imaging capabilities have now made it possible to explore the vertical structure of galaxies billions of light-years away, essentially allowing astronomers to look back in time.
Galactic evolution through times
The analysis of the JWST images revealed a clear evolutionary pattern. In the earlier universe, galaxies appeared to have only a thick disk. As time went on, more galaxies developed a second, thinner disk nestled within the thick one. This sequence suggests a two-step formation process: galaxies initially formed a thick disk during their early, chaotic stages, and later developed a thin disk as they matured.
The team found that the thin disks in galaxies similar in size to the Milky Way began forming about 8 billion years ago. This timeline matches with existing data on our galaxy, suggesting that the Milky Way’s formation history may be more typical than previously thought.
Gas, turbulence, and the birth of stars
To understand how these disks formed, the researchers also examined data from the Atacama Large Millimetre/submillimeter Array (ALMA) and other ground-based observatories. These observations focused on the motion of gas, the raw material from which stars are born.
In the early universe, galaxies were gas-rich and highly turbulent. This chaotic environment fueled rapid star formation, resulting in the formation of thick stellar disks. Over time, the stars themselves helped stabilise the gas, calming the turbulence. This quieter environment allowed for the gradual buildup of a thin, more orderly disk within the thick one.
Massive galaxies, with more gas and stronger gravitational pull, were able to form thin disks earlier than smaller galaxies. This suggests that galaxy mass plays a crucial role in shaping the development of disk structures.
When thinking about fossils, we often picture dinosaurs. But reefs can also hold an ancient history. Tiny fish bones and shark scales also become fossils in these habitats, quietly preserving the story of ancient oceans.
A striking study from the Smithsonian Tropical Research Institute (STRI) has now revealed how humans disrupted Caribbean reefs in the past.
Scientists analyzed fossilized coral reefs from Panama’s Bocas del Toro and the Dominican Republic. These reefs, exposed and well-preserved, date back 7,000 years.
Humans changed reef fish communities
The researchers compared the fossilized reefs with nearby living reefs to reveal how overfishing changed fish communities.
In the ancient reef sediments, the team found thousands of fossilized otoliths (fish ear bones) and dermal denticles (shark scales).
These fossils gave clues to species composition and size. The results show a massive shift in predator-prey dynamics, unlike anything seen before.
One of the most alarming findings was a 75% drop in shark numbers. These top predators once played a key role in maintaining reef balance. As their numbers fell, populations of prey fish surged. They doubled in abundance and increased 17% in size.
The predator release effect
The study offers hard evidence for the “predator release effect.” Scientists had long predicted this outcome, but they lacked solid prehistoric data to prove it.
Now, the fossils confirm what models once assumed: removing predators lets prey populations explode.
Meanwhile, fish targeted by humans, like larger groupers and snappers, became 22% smaller. This shrinking trend matches what we observe today.
Overfishing seems to have pushed these species toward early maturity and smaller size.
Some fish stay the same
Remains from tiny cryptobenthic reef fishes, which live in coral crevices, told a different story. Their size and abundance remained unchanged over thousands of years.
Despite fishing and upheaval above them, these reef dwellers stayed stable. Their resilience surprised the researchers.
“The stability of these fish shows remarkable resistance to external pressures,” noted the researchers. Even as top predators vanished and fishing intensified, these hidden species kept going, unchanged.
To measure these shifts, the scientists examined 807 shark denticles and 5,724 otoliths. They also studied coral branches for bite marks left by damselfish.
Fossil and modern samples showed that damselfish now bite more often – likely because they face fewer predators.
Fish bones reveal big reef changes
Otoliths grow in layers like tree rings. This allows scientists to estimate the age and size of fish at time of death. By comparing fossil otoliths with modern ones, researchers could track size changes across millennia.
Dermal denticles, the scale-like structures on shark skin, helped identify shark presence. These tiny features tell a big story: as shark numbers decreased, populations of prey species expanded.
Fish otoliths – the calcium carbonate structures found in fishes’ inner ears – from human harvested fish, prey fish (those eaten by predatory fish) and reef-sheltered fish (also known as cryptobentic fish) found in 7000 year-old fossilized Caribbean reefs from Panama and the Dominican Republic. Click image to enlarge. Credit: Erin Dillon
Bite marks from damselfish also gave insights. These aggressive little fish defend territories and leave distinct marks. More bites today means more damselfish – again pointing to the effects of predator loss.
Tracing reef fish history with fossils
This fossil evidence gives scientists a rare and valuable baseline. It shows how Caribbean reef fish communities looked before human fishing began to alter their structure.
Without such deep-time context, conservation efforts often rely on incomplete or recent data that miss the full picture of ecological change.
Now, researchers and reef managers can clearly see which parts of the reef ecosystem shifted due to human influence – and which components, like tiny reef-sheltered fish, remained stable across millennia.
“This study demonstrates the power of the fossil record for future conservation,” the researchers stated.
Long-term impacts of human activity
These 7,000-year-old fossils give us a clearer view of the long-term impacts of human activity on reef food webs, fish sizes, and predator-prey dynamics.
They also help identify which reef species and relationships are most at risk from continued pressure.
By looking back in time through the fossil record, scientists gain crucial insight to guide better decisions in reef conservation, fishing policies, and biodiversity management today.
Discovering and studying prehistoric coral reefs on dry land.
The research was a collaboration among top institutions including the Smithsonian Tropical Research Institute (STRI), the Marine Science Institute at the University of Texas, Austin, and the Center for Biodiversity Outcomes at Arizona State University.
The study is published in the journal Proceedings of the National Academy of Sciences.
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