Scientists use the bony plates that make up aetosaur armor to identify different species and usually don’t have many fossil skeletons to work with. But a new study led by researchers at The University of Texas at Austin centers on an aetosaur suit of armor that has most of its major parts intact.

The suit — called a carapace — is about 70% complete and covers each major region of the body.

“We have elements from the back of the neck and shoulder region all the way to the tip of the tail,” said William Reyes, a doctoral student at the UT Jackson School of Geosciences who led the research. “Usually, you find very limited material.”

The research was published in The Anatomical Record.

Reyes and his collaborators used the armor to identify the specimen as a new aetosaur species — which they named Garzapelta muelleri. The name “Garza” recognizes Garza County in northwest Texas, where the aetosaur was found, and “Pelta” is Latin for shield, a nod to aetosaurs’ heavily fortified body. The species name “muelleri” honors the paleontologist who originally discovered it, Bill Mueller.

Garzapelta lived about 215 million years ago and resembled a modern American crocodile — but with much more armor.

“Take a crocodile from modern day, and turn it into an armadillo,” said Reyes.

The bony plates that covered Garzapelta and other aetosaurs are called osteoderms. They were embedded directly in the skin and formed a suit of armor by fitting together like a mosaic. In addition to having a body covered in bony plates, Garzapelta’s sides were flanked by curved spikes that would have offered another layer of protection from predators. Although crocodiles today are carnivores, scientists think that aetosaurs were primarily omnivorous.

The spikes on Garzapelta are very similar to those found in another aetosaur species, but surprisingly, researchers found that the two species are only distantly related. The similarities, they discovered, are an example of convergent evolution, the independent evolution of similar traits in different species. The development of flight in insects, birds, mammals and now-extinct pterosaurs is a classic example of this phenomenon.

According to Reyes, an array of unique features on Garzapelta’s plates clearly marked it as a new species. They range from how the plates fit together to unique bumps and ridges on the bones. However, figuring out where Garzapelta fit into the larger aetosaur family tree was more of challenge. Depending on which portion of the armor the researchers emphasized in their analysis, Garzapelta would end up in very different places. Armor that ran down its back resembled armor from one species, while its midsection spikes resembled armor from another.

Once the researchers determined that the spikes evolved independently, they were able to work out where Garzapelta fit best among other aetosaur species. Nevertheless, Reyes said the research shows how convergent evolution can complicate things.

“Convergence of the osteoderms across distantly related aetosaurs has been noted before, but the carapace of Garzapelta muelleri is the best example of it and shows to what extent it can happen and the problems it causes in our phylogenetic analyses,” Reyes said.

Garzapelta is part of the Texas Tech University fossil collections. It spent most of the past 30 years on a shelf before Reyes encountered it during a visit. Bill Parker, an aetosaur expert and park paleontologist at Petrified Forest National Park who was not part of the research, said that university and museum collections are a critical part of making this type of research possible.

“These specimens weren’t just dug in the field yesterday,” he said. “They’ve been sitting in the museum for decades and it just takes someone like Will to come along and finally decide to study them and make them come to life.”

In addition to different species having different armor, it’s possible that an animal’s age or sex could also affect armor appearance. Reyes is currently exploring these questions by studying aetosaur fossils in the Jackson School’s collection, most of which were found during the 1940s as part of excavations done by the Works Progress Administration.

The research was funded by the National Science Foundation and the Jackson School.

The study co-authors are Jeffrey Martz, an associate professor at the University of Houston-Downtown, and Bryan Small, a research associate at the Museum of Texas Tech University.

This could allow the development of bioinspired optical materials with possible applications ranging from invisible cloaking devices to coatings to more efficiently harvest solar energy, said Tak-Sing Wong, professor of mechanical engineering and biomedical engineering. Wong led the study, which was published today (March 18) in the Proceedings of the National Academy of Sciences of the United States of America (PNAS).

The unique, tiny particles have an unusual soccer ball-like geometry with cavities, and their exact purpose for the insects has been something of a mystery to scientists since the 1950s. In 2017, Wong led the Penn State research team that was the first to create a basic, synthetic version of brochosomes in an effort to better understand their function.

“This discovery could be very useful for technological innovation,” said Lin Wang, postdoctoral scholar in mechanical engineering and the lead author of the study. “With a new strategy to regulate light reflection on a surface, we might be able to hide the thermal signatures of humans or machines. Perhaps someday people could develop a thermal invisibility cloak based on the tricks used by leafhoppers. Our work shows how understanding nature can help us develop modern technologies.”

Wang went on to explain that even though scientists have known about brochosome particles for three-quarters of a century, making them in a lab has been a challenge due to the complexity of the particle’s geometry.

“It has been unclear why the leafhoppers produce particles with such complex structures,” Wang said, “We managed to make these brochosomes using a high-tech 3D-printing method in the lab. We found that these lab-made particles can reduce light reflection by up to 94%. This is a big discovery because it’s the first time we’ve seen nature do something like this, where it controls light in such a specific way using hollow particles.”

Theories on why leafhoppers coat themselves with a brochosome armor have ranged from keeping them free of contaminants and water to a superhero-like invisibility cloak. However, a new understanding of their geometry raises a strong possibility that its main purpose could be the cloak to avoid predators, according to Tak-Sing Wong, professor of mechanical engineering and biomedical engineering and corresponding author of the study.

The researchers have found that the size of the holes in the brochosome that give it a hollow, soccer ball-like appearance is extremely important. The size is consistent across leafhopper species, no matter the size of the insect’s body. The brochosomes are roughly 600 nanometers in diameter — about half the size of a single bacterium — and the brochosome pores are around 200 nanometers.

“That makes us ask a question,” Wong said. “Why this consistency? What is the secret of having brochosomes of about 600 nanometers with about 200-nanometer pores? Does that serve some purpose?”

The researchers found the unique design of brochosomes serves a dual purpose — absorbing ultraviolet (UV) light, which reduces visibility to predators with UV vision, such as birds and reptiles, and scattering visible light, creating an anti-reflective shield against potential threats. The size of the holes is perfect for absorbing light at the ultraviolet frequency.

This potentially could lead to a variety of applications for humans using synthetic brochosomes, such as more efficient solar energy harvesting systems, coatings that protect pharmaceuticals from light-induced damage, advanced sunscreens for better skin protection against sun damage and even cloaking devices, researchers said. To test this, the team first had to make synthetic brochosomes, a major challenge in and of itself.

In their 2017 study, the researchers mimicked some features of brochosomes, particularly the dimples and their distribution, using synthetic materials. This allowed them to begin understanding the optical properties. However, they were only able to make something that looked like brochosomes, not an exact replica.

“This is the first time we are able to make the exact geometry of the natural brochosome,” Wong said, explaining that the researchers were able to create scaled synthetic replicas of the brochosome structures by using advanced 3D-printing technology.

They printed a scaled-up version that was 20,000 nanometers in size, or roughly one-fifth the diameter of a human hair. The researchers precisely replicated the shape and morphology, as well as the number and placement of pores using 3D printing, to produce still-small faux brochosomes that were large enough to characterize optically.

They used a Micro-Fourier transform infrared (FTIR) spectrometer to examine how the brochosomes interacted with infrared light of different wavelengths, helping the researchers understand how the structures manipulate the light.

Next, the researchers said they plan to improve the synthetic brochosome fabrication to enable production at a scale closer to the size of natural brochosomes. They will also explore additional applications for synthetic brochosomes, such as information encryption, where brochosome-like structures could be used as part of an encryption system where data is only visible under certain light wavelengths.

Wang noted that their brochosome work demonstrates the value of a biomimetic research approach, where scientists looks to nature for inspiration.

“Nature has been a good teacher for scientists to develop novel advanced materials,” Wang said. “In this study, we have just focused on one insect species, but there are many more amazing insects out there that are waiting for material scientists to study, and they may be able to help us solve various engineering problems. They are not just bugs; they are inspirations.”

Along with Wong and Wang from Penn State, other researchers on the study include Sheng Shen, professor of mechanical engineering, and Zhuo Li, doctoral candidate in mechanical engineering, both at Carnegie Mellon University, who contributed to the simulations in this study. Wang and Li contributed equally to this work, for which the researchers have filed a U.S. provisional patent. The Office of Naval Research supported this research.

Performing a new task without prior training, on the sole basis of verbal or written instructions, is a unique human ability. What’s more, once we have learned the task, we are able to describe it so that another person can reproduce it. This dual capacity distinguishes us from other species which, to learn a new task, need numerous trials accompanied by positive or negative reinforcement signals, without being able to communicate it to their congeners.

A sub-field of artificial intelligence (AI) — Natural language processing — seeks to recreate this human faculty, with machines that understand and respond to vocal or textual data. This technique is based on artificial neural networks, inspired by our biological neurons and by the way they transmit electrical signals to each other in the brain. However, the neural calculations that would make it possible to achieve the cognitive feat described above are still poorly understood.

”Currently, conversational agents using AI are capable of integrating linguistic information to produce text or an image. But, as far as we know, they are not yet capable of translating a verbal or written instruction into a sensorimotor action, and even less explaining it to another artificial intelligence so that it can reproduce it,” explains Alexandre Pouget, full professor in the Department of Basic Neurosciences at the UNIGE Faculty of Medicine.

A model brain

The researcher and his team have succeeded in developing an artificial neuronal model with this dual capacity, albeit with prior training. ”We started with an existing model of artificial neurons, S-Bert, which has 300 million neurons and is pre-trained to understand language. We ‘connected’ it to another, simpler network of a few thousand neurons,” explains Reidar Riveland, a PhD student in the Department of Basic Neurosciences at the UNIGE Faculty of Medicine, and first author of the study.

In the first stage of the experiment, the neuroscientists trained this network to simulate Wernicke’s area, the part of our brain that enables us to perceive and interpret language. In the second stage, the network was trained to reproduce Broca’s area, which, under the influence of Wernicke’s area, is responsible for producing and articulating words. The entire process was carried out on conventional laptop computers. Written instructions in English were then transmitted to the AI.

For example: pointing to the location — left or right — where a stimulus is perceived; responding in the opposite direction of a stimulus; or, more complex, between two visual stimuli with a slight difference in contrast, showing the brighter one. The scientists then evaluated the results of the model, which simulated the intention of moving, or in this case pointing. ”Once these tasks had been learned, the network was able to describe them to a second network — a copy of the first — so that it could reproduce them. To our knowledge, this is the first time that two AIs have been able to talk to each other in a purely linguistic way,” says Alexandre Pouget, who led the research.

For future humanoids

This model opens new horizons for understanding the interaction between language and behaviour. It is particularly promising for the robotics sector, where the development of technologies that enable machines to talk to each other is a key issue. ”The network we have developed is very small. Nothing now stands in the way of developing, on this basis, much more complex networks that would be integrated into humanoid robots capable of understanding us but also of understanding each other,” conclude the two researchers.

But University of Michigan scientists are looking at something a little more tangible: coral.

Examining samples from corals in the Great Barrier Reef, the researchers discovered between 1750 and present day, as the global climate warmed, wet-season rainfall in that part of the world increased by about 10%, and the rate of extreme rain events more than doubled. Their results are published in Nature, Communications Earth and Environment.

“Climate scientists often find themselves saying, ‘I knew it was going to get bad, but I didn’t think it was going to get this bad this fast.’ But we’re actually seeing it in this coral record,” said principal investigator Julia Cole, chair of the U-M Department of Earth and Environmental Sciences.

“Studies of the future tend to use climate models and those models can give different results. Some may say more rainfall, some they say less rainfall. We’re showing that, at least in northeastern Queensland, there is definitely more rainfall, it’s definitely more variable and it’s definitely already happening.”

The study, led by U-M researcher Kelsey Dyez, analyzed core samples drilled from a coral colony situated at the mouth of a river in northern Queensland, Australia. During the summer rainy seasons, rainfall filtering into the river picks up nutrients, organic material and sediments, which are then carried to the river mouth and discharged into the ocean, washing over the coral colony.

As the corals are bathed in this freshwater outflow, they pick up geochemical signals from the river and record them into their carbonate skeletons. The core samples of the corals display faint bands of lighter and darker material. These bands reflect each rainy and dry season the coral lived through. The bands also hold information about the climate in each season, just as trees’ rings record climate patterns during the years it grows.

“We want to know, as we warm the earth, are we going to have more rainfall? Less rainfall? Maybe different parts of the Earth will respond differently?” Dyez said. “This project is especially important because we’re able to put that warming and changes into context. We are able to record rainfall from the period before we have instrumental records for this part of the world.”

To accurately determine how much rain fell each rainy season, and how many extreme rain events occurred during each season, the researchers compared instrumental rainfall records that began in the 1950s to the corresponding years in the coral. This gave the researchers a calibration period that they could use to determine the relationship between the coral characteristics and the amount of rainfall that fell each rainy season as long as the corals were alive, all the way back to 1750.

The coral core was taken from a remote region off northeastern Queensland by the Australian Institute of Marine Science. The land surrounding the river watershed is also in a protected area, meaning that nutrients and sediment flushed into the river by rains are unlikely to be generated by human activity.

“This is a region that has experienced pretty big swings in recent years between floods that have been devastating to communities, and then drier periods,” Cole said. “Because northeastern Australia is an agricultural region, how rainfall changes in a warmer world is of real tangible importance. People might not sense a few degrees Celsius of warming, but they really suffer if there’s a drought or a flood.”

To reconstruct rainfall, the researchers used four different measures. First, the researchers looked at the luminescence of the bands in the coral. When they shine a black light on the coral, organic compounds in the coral cause it to fluoresce. The brighter the band fluoresces, the more organic compounds came down the river and were deposited onto the coral, reflecting a season of heavy rainfall.

The researchers also measured how much of the element barium is contained in each of the bands. The coral skeleton is composed of calcium, but when barium is deposited onto the skeleton, it can replace calcium. The more barium detected in the band, the more river discharge was flowing over the coral.

The researchers then looked at stable carbon isotopes (carbon-12 and carbon-13) within the coral. The more the ratio of these two isotopes favors carbon-12, the more water must have been coming down the river from greater rainfall.

Finally, the researchers examined stable oxygen isotopes (oxygen-16 and oxygen-18). When the ratio of these two isotopes favors oxygen-16, it is a signature of additional precipitation and freshwater coming down the river.

Because the coral record is located off northeastern Australia, the researchers wanted to understand if the whole of Australia experienced similar rainfall. Looking at instrumental rainfall records across Australia, the researchers found that the increased rainfall patterns did not occur evenly across Australia.

“It’s not actually that well correlated to western Australia. That’s too far away. But for most of eastern Australia, there is a significant correlation. And that’s where many people live,” Dyez said. “It’s especially strong across Queensland, which is where a lot of these rainfall extremes are happening right now.”

However, if the aim is simply to store data in a physical object, then holography can be done quite easily, as has now been demonstrated at TU Wien: A 3D printer can be used to produce a panel from normal plastic in which a QR code can be stored, for example. The message is read using terahertz rays — electromagnetic radiation that is invisible to the human eye.

The hologram as a data storage device

A hologram is completely different from an ordinary image. In an ordinary image, each pixel has a clearly defined position. If you tear off a piece of the picture, a part of the content is lost.

In a hologram, however, the image is formed by contributions from all areas of the hologram simultaneously. If you take away a piece of the hologram, the rest can still create the complete image (albeit perhaps a blurrier version). With the hologram, the information is not stored pixel by pixel, but rather, all of the information is spread out over the whole hologram.

“We have applied this principle to terahertz beams,” says Evan Constable from the Institute of Solid State Physics at TU Wien. “These are electromagnetic rays in the range of around one hundred to several thousand gigahertz, comparable to the radiation of a cell phone or a microwave oven — but with a significantly higher frequency.”

This terahertz radiation is sent to a thin plastic plate. This plate is almost transparent to the terahertz rays, but it has a higher refractive index than the surrounding air, so at each point of the plate, it changes the incident wave a little. “A wave then emanates from each point of the plate, and all these waves interfere with each other,” says Evan Constable. “If you have adjusted the thickness of the plate in just the right way, point by point, then the superposition of all these waves produces exactly the desired image.”

It is similar to throwing lots of little stones into a pond in a precisely calculated way so that the water waves from all these stones add up to a very specific overall wave pattern.

A piece of cheap plastic as a high-tech storage unit for valuable items

In this way, it was possible to encode a Bitcoin wallet address (consisting of 256 bits) in a piece of plastic. By shining terahertz rays of the correct wavelength through this plastic plate, a terahertz ray image is created that produces exactly the desired code. “In this way, you can securely store a value of tens of thousands of euros in an object that only costs a few cents,” says Evan Constable.

In order for the plate to generate the correct code, one first has to calculate how thick the plate has to be at each point, so that it changes the terahertz wave in exactly the right way. Evan Constable and his collaborators made the code for obtaining this thickness profile available for free on Github. “Once you have this thickness profile, all you need is an ordinary 3D printer to print the plate and you have the desired information stored holographically,” explains Constable. The aim of the research work was not only to make holography with terahertz waves possible, but also to demonstrate how well the technology for working with these waves has progressed and how precisely this still rather unusual range of electromagnetic radiation can already be used today.

Instead, techniques often used to address stress — deep breathing, mindfulness, meditation, yoga or even counting to 10 — have been shown to be more effective at decreasing anger and aggression.

Researchers analyzed over 150 studies involving more than 10,000 participants and found that what really works to reduce anger is lowering physiological arousal — in other words, turning down the heat. Activities that increased arousal overall had no effect on anger, and some activities made it worse — particularly jogging.

“I think it’s really important to bust the myth that if you’re angry you should blow off steam — get it off your chest,” said senior author Brad Bushman, professor of communication at The Ohio State University. “Venting anger might sound like a good idea, but there’s not a shred of scientific evidence to support catharsis theory.

“To reduce anger, it is better to engage in activities that decrease arousal levels,” Bushman said. “Despite what popular wisdom may suggest, even going for a run is not an effective strategy because it increases arousal levels and ends up being counterproductive.”

The study was led by first author Sophie Kjærvik, who completed the review for her Ohio State dissertation. It was published online March 11 in the journal Clinical Psychology Review.

Kjærvik, now a postdoctoral fellow at Virginia Commonwealth University, said the work was inspired in part by the rising popularity of rage rooms that promote smashing things (such as glass, plates and electronics) to work through angry feelings.

“I wanted to debunk the whole theory of expressing anger as a way of coping with it,” she said. “We wanted to show that reducing arousal, and actually the physiological aspect of it, is really important.”

The meta-analytic review was based on 154 studies involving 10,189 participants of different genders, races, ages and cultures. The study selection and analysis were guided by the Schachter-Singer two-factor theory, which assumes that all emotions, including anger, consist of physiological arousal and mental meanings. To get rid of anger, you can work on either of those.

Several previous meta-analytic reviews have focused on changing mental meanings using cognitive behavioral therapy, which works. However, Kjærvik and Bushman said a meta-analytic review on the role of arousal would fill an important gap in understanding how to resolve anger. Their analysis focused on examining both arousal-increasing activities (e.g., hitting a bag, jogging, cycling, swimming) and arousal-decreasing activities (e.g., deep breathing, mindfulness, meditation, yoga).

Results showed that arousal-decreasing activities were effective at fending off the fury in labs and field settings, using digital platforms or in-person instruction, and in group and individual sessions across multiple populations: college students and non-students, people with and without a criminal history, and individuals with and without intellectual disabilities.

Arousal-decreasing activities that were effective at lowering anger across the board included deep breathing, relaxation, mindfulness, meditation, slow flow yoga, progressive muscle relaxation, diaphragmic breathing and taking a timeout.

“It was really interesting to see that progressive muscle relaxation and just relaxation in general might be as effective as approaches such as mindfulness and meditation,” Kjærvik said. “And yoga, which can be more arousing than meditation and mindfulness, is still a way of calming and focusing on your breath that has the similar effect in reducing anger.

“Obviously in today’s society, we’re all dealing with a lot of stress, and we need ways of coping with that, too. Showing that the same strategies that work for stress actually also work for anger is beneficial.”

In contrast, activities that increased arousal were generally ineffective, but also produced a complex range of outcomes. Jogging was the most likely to increase anger, while physical education classes and playing ball sports had an arousal-decreasing effect — suggesting to the researchers that introducing an element of play into physical activity may at least increase positive emotions or counteract negative feelings.

Finding that increasing arousal was not the answer to anger corresponded with previous work led by Bushman that linked venting anger with continued aggression.

“Certain physical activities that increase arousal may be good for your heart, but they’re definitely not the best way to reduce anger,” Bushman said. “It’s really a battle because angry people want to vent, but our research shows that any good feeling we get from venting actually reinforces aggression.”

That being the case, the authors noted that many arousal-decreasing interventions shown to lower the heat of anger are free or inexpensive and easy to access.

“You don’t need to necessarily book an appointment with a cognitive behavioral therapist to deal with anger. You can download an app for free on your phone, or you can find a YouTube video if you need guidance,” Kjærvik said.