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New Troodontid Dinosaur with Thick Skull Discovered in Mexico

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A groundbreaking study by a team of paleontologists from Mexico and the United States has unveiled a new species of bird-like dinosaur, Xenovenator Espinosai, notable for its exceptionally thick, dome-shaped skull. This unique adaptation suggests it may have engaged in headbutting behaviors during conflicts with its peers.

Reconstruction of the life of Xenovenator Espinosai. Image credit: Connor Ashbridge / CC BY 4.0.

This newly identified dinosaur species thrived during the late Cretaceous period, approximately 73 million years ago.

Xenovenator Espinosai is part of the Troodontidae family, which includes agile theropod dinosaurs closely related to modern birds.

The holotype and paratype specimens were uncovered during surface sampling in the Cerro del Pueblo Formation located in Coahuila state, northern Mexico, in the early 2000s.

While Troodontids are recognized for their larger brains and heightened sensory capabilities, this species distinguishes itself through an exceptionally thick skull roof.

The holotype specimen retains nearly the entire brain case, showcasing a strongly dome-shaped structure that reaches thicknesses of up to 1.2 cm.

CT scans reveal that the skull features a dense architecture with closely interlocked sutures and a rugged, textured exterior.

This structural resemblance to the reinforced skulls of dome-headed pachycephalosaurs highlights an evolutionary adaptation for intraspecific combat, particularly head-butting.

While display structures and combat weapons are common among many dinosaur species, detailed adaptations for fighting have yet to be recorded in non-avian maniraptoran theropods.

The paratype specimen of Xenovenator Espinosai shows less pronounced cranial thickening, which may indicate variability due to age or sex, suggesting that the most significant skull enhancements occurred later in development or were selective to one sex.

“The thickened, deformed skull of Xenovenator Espinosai is unparalleled among maniraptorans, with its precise function remaining unclear,” stated lead author Dr. Hector Rivera Silva from Museo del Desierto.

“Several traits that appear to serve no obvious survival advantage, such as cranial horns and crests, may be the result of sexual selection.”

“In contemporary mammals and birds, these attributes can be utilized for display or as weapons during courtship.”

“Considering our findings—skull thickening, cranial doming, and intricate sutures—it is likely that the domed skull of Xenovenator Espinosai was an adaptation for intraspecific combat,” they added.

This discovery marks the first documented case of a parabird exhibiting a specialized skull for combat among its species.

Interestingly, researchers noted that wrinkled frontal bones and similar features in the maxilla and nasal bones of troodontids may suggest widespread intraspecific fighting, with heightened intensity observed in Xenovenator Espinosai.

The phylogenetic analysis indicates that despite being part of a larger North American troodontid lineage, Xenovenator Espinosai’s distinctively thick, domed skull highlights its unique evolutionary niche within the group.

The recurrent evolution of intricate display features and weapons during the Cretaceous hints at the increasing importance of sexual selection in dinosaur evolution.

This finding enriches our understanding of the diversity among troodontid dinosaurs from southern Laramidia, offering rare insights into how even smaller, lighter theropods developed traits specialized for physical confrontation.

Researchers propose that related species like Xenovenator Robustus signify a distinct clade of heavily built troodontids endemic to the Southwest, emphasizing the uniqueness and diversity of southern Laramidian fauna.

“Sexual selection, encompassing adaptations for display and combat, was likely a pervasive phenomenon among dinosaurs during the Late Cretaceous period,” they concluded.

For further details on this discovery, refer to the research paper published in the journal Diversity.

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Hector E. Rivera-Silva et al. 2026. A troodontid theropod with a thick skull that lived in late Cretaceous Mexico. Diversity 18(1):38; doi: 10.3390/d18010038

Source: www.sci.news

How Europa’s Thick Ice May Obstruct the Hunt for Ocean Life

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Europa’s Ice: A Thick Shell Over a Salty Ocean

Claudio Caridi / Alamy

Europa, one of Jupiter’s intriguing moons, features a liquid ocean possibly encased beneath a thick layer of ice, estimated to be six times the depth of Antarctica’s icy crust, complicating our efforts to detect any potential lifeforms.

This moon is a leading candidate in the search for extraterrestrial life, primarily due to its significant volume of liquid water.

Previously, estimates regarding the thickness of Europa’s ice have varied dramatically—ranging from under 10 kilometers to nearly 50 kilometers. Researchers initially believed certain defects in the ice might permit nutrient exchange between the surface and the ocean below.

Now, a research team, led by Stephen Levin from the California Institute of Technology, has analyzed data collected by the Juno spacecraft, which has been orbiting Jupiter since 2016.

On September 29, 2022, Juno came within 360 kilometers of Europa, utilizing its microwave radiometer to scan the surface and perform the first direct measurements of the ice layer. Levin noted that this instrument assessed the heat emitted by Europa’s icy exterior, enabling the measurement of ice temperatures at various depths and detecting temperature fluctuations resulting from imperfections in the ice sheet.

The researchers estimate that the most accurate thickness of the ice sheet is approximately 29 kilometers, aligning with the higher range of previous estimates while presenting a possible thickness that could range from 19 kilometers to 39 kilometers.

Crucially, their findings indicate that the fissures, pores, and other imperfections likely extend only a few hundred meters beneath the surface, with pore diameters measuring only a few centimeters.

“This indicates that the observed defects in the microwave radiometers are insufficiently deep or expansive to facilitate significant nutrient transport between the ocean and the surface,” asserts Levin.

Nonetheless, this does not diminish the potential for life on Europa. Levin further explains, “Though the observed pores and cracks are too minute and shallow to transport nutrients, alternative transportation mechanisms may exist.”

There may also be unexplored regions of the moon where conditions differ, he adds.

Researchers including Ben Montet from the University of New South Wales in Sydney, express concerns that the ice thickness could hinder life’s search. “While this protection may sustain life for extended durations, it complicates our ability to penetrate the ice and study the ocean beneath,” he notes.

He argues that life could exist without a direct link between Europa’s surface and its subterranean ocean, though such a connection would enhance the chances of discovering life. Helen Maynard-Casley of the Australian Nuclear Science and Technology Agency emphasizes that without that transport link, “you’re essentially confined to whatever was in the ocean initially.”

NASA has plans to launch the Europa Clipper spacecraft in 2024, aiming to embark on its mission to Jupiter’s moons in 2030. This spacecraft is expected to provide clearer insights into Europa’s icy layer, according to Maynard-Casley.

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Source: www.newscientist.com

Memory Chips Just 10 Atoms Thick Could Boost Capacity Significantly

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Current silicon chips are highly compact, but using ultrathin 2D materials could enhance their density even further.

Wu Kailiang/Alamy

A memory chip with a thickness of just 10 atoms could revolutionize the storage capacity of electronic gadgets like smartphones.

Despite decades of scaling down, modern computer chips often have very few components yet integrate tens of billions of transistors into an area comparable to a fingernail. Although the size of silicon components has significantly decreased, the thickness of the silicon wafers remains considerable, imposing limitations on increasing a chip’s complexity through stacking layers.

Researchers have been exploring the potential of thinner chips made from 2D materials like graphene. Graphene consists of a single layer of carbon atoms and represents the thinnest known material. However, until recently, only basic chip designs could be implemented with these materials, complicating their connection to traditional processors and integration into electrical devices.

Recently, Liu Chunsen and his team from Fudan University in Shanghai successfully integrated a 2D chip only 10 atoms thick with a CMOS chip currently utilized in computers. The manufacturing method for these chips yields a rough surface, making it challenging to layer a 2D sheet on top. The researchers addressed this issue by placing a glass layer between the 2D and CMOS chips, although this step is not yet part of the industrial process and requires further development for mass production.

The prototype memory module the team created achieved over 93% accuracy during testing. While this falls short of the reliability needed for consumer-grade devices, it serves as an encouraging proof of concept.

“This technology holds significant promise, but there’s still a considerable journey ahead before it can be commercialized,” says Steve Furber from the University of Manchester, UK.

Kai Shu, a researcher at King’s College London, mentions that further reducing current chip designs without utilizing 2D materials poses challenges due to signal leakage associated with traditional components made at very narrow widths. Thinner layers might mitigate this issue. Consequently, achieving greater thinness may facilitate additional reductions in width.

“Silicon is encountering hurdles,” said Xu. “2D materials might provide solutions. With their minimal thickness, gate control becomes more uniform and comprehensive, resulting in reduced leakage.”

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Source: www.newscientist.com

Metals can be thinned to a few atoms thick

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Two layers of bismuth sandwiched between two layers of disulphide

Luo Jun Du

By crushing the molten droplets at a large pressure between two sapphires, a sheet of thick atoms of two thick atoms can be produced. Researchers who developed the process say that rare materials can use applications in industrial chemistry, optics, and computers.

Last year, scientists created a golden sheet Thick single atom which was called “Galden” after graphene, a material made from a single layer of carbon atoms. Such materials are described as 2D because they are chemically as thin as possible.

However, it has never been possible to make other 2D metals. New techniques developed by Luo Jun Du The Chinese Academy of Sciences and his colleagues can create two sheets of bismuth, gallium, indium, tin, and lead, which are as thin as atomic bonds allow.

To squeeze the metals, the researchers used two very flat sapphire crystals with a thin layer of disulfide in a bilayer (MOS2). They placed powdered metal between these jaws, heated to 400°C until they formed droplets, crushing them with a huge pressure of up to 200 megapascals. The metal was compressed until it cooled to just two atoms thick, or, in the case of bismuth. When the pressure was removed, the 2D metal was stuck between the MOS2. The seat then slipped out of the sapphire.

Du says the process was devised eight years ago, but the team dug up the recent fruit when MOS discovered it2. The layers remained the thin metal sheet stable. “The single layer of freestanding metal atoms is simply unstable from a thermodynamic perspective. Therefore, we [had to] We’re developing whole new techniques,” says Du. “The process seems simple, but it works.”

In addition to creating very thin layers of atoms, researchers were able to fine-tune the throttle pressure and create three, four, or more atoms with accuracy.

2D metals can have anomalous properties that help scientists explore macroscopic quantum phenomena and superconductivity, DU says, which could lead to ultra-low power transistors, clear computer displays, and highly efficient catalysts for chemical reactions.

One problem is MOS2 Encapsulating metal sheets is not easily removed. DU says this may be problematic in some applications, but the experiments suggest that it does not affect electrical conductivity, thus not hindering the 2D metal used in electronic devices.

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Source: www.newscientist.com

Research: Thick plant populations move to shade one another and share sunlight

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Typically, plants grow in crowded environments where neighboring plants compete for light while shading each other. The presence of neighboring plants varies through space and time, and plants have developed the ability to detect neighboring plants and grow away from their shade. Although it is generally accepted that these responses help plants increase their individual light exposure, it is not clear how plants find solutions that are beneficial for them as a whole. In a new study, physicists from Tel Aviv University and elsewhere focus on the spontaneous self-organized pattern formation of sunflower flocks mediated by shade avoidance. Their analysis reveals that circumnavigation (the innate movement of plants) results in random perturbations that follow a restricted random walk.

Circling is widespread in plant systems and is commonly associated with exploratory behavior, but its role is difficult to quantitatively understand. otherswere the first to report their role in promoting optimal growth patterns in dense plant populations that shade each other. Image courtesy of Manuel H.

“Previous studies have shown that when sunflowers are planted close together in a field and shade each other, they will grow in a zigzag pattern, one forward and one backward, to avoid shading each other,” said Professor Yasmin Meros of Tel Aviv University.

“That way the plants can grow side by side, maximizing the light they receive from the sun and maximizing photosynthesis overall.”

“In fact, plants know how to distinguish between the shadow of a building and the green shadow of their leaves.”

“When they sense the shadow of a building, they usually don't change their growth direction because they know it won't have any effect.”

“But when a plant senses shadow, it grows away from the shadow.”

In this study, the researchers investigated the question of how sunflowers “know” how to grow optimally (i.e. to capture the most sunlight collectively) and analysed the growth dynamics of sunflowers in the lab that exhibit a zigzag pattern.

Meros and his colleagues grew sunflowers in high-density environments, photographing them every few minutes as they grew, and then stitched together the images to create a time-lapse video.

The researchers followed the movements of each sunflower and observed the blossoms dancing en masse.

According to the authors, Darwin was the first to recognise that all plants grow by exhibiting a kind of cyclical movement (circumlocution), and that both stems and roots exhibit this behaviour.

But until now, apart from a few examples such as vines that grow in large circular motions searching for something to grab hold of, it hasn't been clear whether this is an artefact or an important feature of growth. Why would a plant expend energy growing in a random direction?

“As part of our research, we carried out a physical analysis to capture the behaviour of each sunflower in the colony and found that they dance to find the optimal angle to avoid blocking the sunlight of their neighbours,” Professor Meros said.

“We statistically quantified this movement and showed through computer simulations that these random movements are used collectively to minimize the amount of shadowing.”

“We were also very surprised to see that the distribution of sunflower stride lengths was so wide, spanning three orders of magnitude, from nearly zero displacement to moving two centimetres in either direction every few minutes.”

“Sunflower plants take advantage of the fact that they can use both small, slow steps and large, fast steps to find the optimal arrangement for their population,” Professor Meros said.

“That means that if the steps are narrow or wide, the arrangement will increase mutual shading and reduce photosynthesis.”

“It's like a crowded dance party, where people dance around to get more space. If you move too much, you get in the way of the other dancers, but if you move too little, it doesn't solve the crowding problem, because one corner of the square will be very crowded and the other side will be empty.”

“Sunflowers also exhibit similar communication dynamics: a combination of response to the shade of neighboring plants and random movement without regard to external stimuli.”

of result Published in the journal Physical Review X.

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Chantal Nguyen others2024. Noisy turning movements promote self-organized shade avoidance in sunflowers. Physical Review X 14 (3): 031027; doi: 10.1103/PhysRevX.14.031027

Source: www.sci.news

Scientists develop ultra-thin gold ‘golden’ that is only one atom thick

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Golden in the form of gold monolayer sheets is prepared by etching away titanium carbide (Ti)3C2. Slabs of titanium gold carbide (Ti)3AuC2.

Golden preparation.Image provided by: Kashiwaya other., doi: 10.1038/s44160-024-00518-4.

“When you make a material extremely thin, something unusual happens, just as it did with graphene. The same thing happens with gold,” said Dr. Shun Kashiwaya, a researcher at Linköping University.

“As you know, gold is normally a metal, but if it's an atomic layer thick, it can become a semiconductor instead.”

To create Goldene, Dr. Kashiwaya and his colleagues used a three-dimensional substrate with gold embedded between layers of titanium and carbon. However, coming up with a golden turned out to be difficult.

“We created the basic material with a completely different application in mind,” said Professor Lars Hartmann from Linköping University.

“We started with a conductive ceramic called titanium silicon carbide, which has a thin layer of silicon.”

“Then the idea was to coat the material with gold to make the contacts. However, when the component was exposed to high temperatures, the silicon layer inside the substrate was replaced by gold.”

This phenomenon is called intercalation, and what the researchers discovered was titanium-gold carbide.

For several years, authors have been using titanium gold carbide without knowing how the gold could be exfoliated or panned out.

They accidentally discovered a method that has been used in Japanese forging for more than 100 years.

This is called Murakami's reagent, and it etches away carbon residues and changes the color of steel, such as in knife making. However, it was not possible to use exactly the same recipe as the blacksmith.

“We tried varying the concentration of Murakami's reagent and the etching time. One day, one week, one month, several months. What we noticed was that the lower the concentration and the longer the etching process, the better. But even that wasn't enough,” Dr. Kashiwaya said.

Etching must also be performed in the dark, as the reaction produces cyanide, which dissolves the gold when exposed to light. This step was to stabilize the gold sheet.

A surfactant was added to prevent the exposed two-dimensional sheet from curling up. In this case, it is a long molecule, a surfactant, that separates and stabilizes the sheets.

“The golden sheets sit in a solution, a bit like cornflakes in milk. We use a sort of 'sieve' to collect the gold and examine it under an electron microscope to see if we were successful.” We have that,” Dr. Kashiwaya said.

“Golden's new properties are due to the fact that gold has two free bonds when it is two-dimensional.”

“Thanks to this, future applications could include carbon dioxide conversion, hydrogen production catalysts, selective production of value-added chemicals, hydrogen production, water purification, communications, etc.”

“Additionally, the amount of gold used in today's applications can be significantly reduced.”

team's work It was published in the magazine natural synthesis.

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Shin Kashiwaya other. Golden synthesis consisting of a single atomic layer of gold. nut.synthesizer, published online March 18, 2024. doi: 10.1038/s44160-024-00518-4

Source: www.sci.news