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    ‘Electronic skin’ from bio-friendly materials can track human vital signs with ultrahigh precision

    Queen Mary University and University of Sussex researchers have used materials inspired by molecular gastronomy to create smart wearables that surpassed similar devices in terms of strain sensitivity. They integrated graphene into seaweed to create nanocomposite microcapsules for highly tunable and sustainable epidermal electronics. When assembled into networks, the tiny capsules can record muscular, breathing, pulse, and blood pressure measurements in real-time with ultrahigh precision.
    Currently much of the research on nanocomposite-based sensors is related to non-sustainable materials. This means that these devices contribute to plastic waste when they are no longer in use. A new study, published on 28 June in Advanced Functional Materials, shows for the first time that it is possible to combine molecular gastronomy concepts with biodegradable materials to create such devices that are not only environmentally friendly, but also have the potential to outperform the non-sustainable ones.
    Scientists used seaweed and salt, two very commonly used materials in the restaurant industry, to create graphene capsules made up of a solid seaweed/graphene gel layer surrounding a liquid graphene ink core. This technique is similar to how Michelin star restaurants serve capsules with a solid seaweed/raspberry jam layer surrounding a liquid jam core.
    Unlike the molecular gastronomy capsules though, the graphene capsules are very sensitive to pressure; so, when squeezed or compressed, their electrical properties change dramatically. This means that they can be utilised as highly efficient strain sensors and can facilitate the creation of smart wearable skin-on devices for high precision, real-time biomechanical and vital signs measurements.
    Dr Dimitrios Papageorgiou, Lecturer in Materials Science at Queen Mary University of London, said: “By introducing a ground-breaking fusion of culinary artistry and cutting-edge nanotechnology, we harnessed the extraordinary properties of newly-created seaweed-graphene microcapsules that redefine the possibilities of wearable electronics. Our discoveries offer a powerful framework for scientists to reinvent nanocomposite wearable technologies for high precision health diagnostics, while our commitment to recyclable and biodegradable materials is fully aligned with environmentally conscious innovation.”
    This research can now be used as a blueprint by other labs to understand and manipulate the strain sensing properties of similar materials, pushing the concept of nano-based wearable technologies to new heights.
    The environmental impact of plastic waste has had a profound effect on our livelihoods and there is a need for future plastic-based epidermal electronics to trend towards more sustainable approaches. The fact that these capsules are made using recyclable and biodegradable materials could impact the way we think about wearable sensing devices and the effect of their presence.
    Dr Papageorgiou said: “We are also very proud of the collaborative effort between Dr Conor Boland’s group from University of Sussex and my group from Queen Mary University of London that fuelled this ground-breaking research. This partnership exemplifies the power of scientific collaboration, bringing together diverse expertise to push the boundaries of innovation.” More

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    Research breakthrough could be significant for quantum computing future

    Scientists using one of the world’s most powerful quantum microscopes have made a discovery that could have significant consequences for the future of computing.
    Researchers at the Macroscopic Quantum Matter Group laboratory in University College Cork (UCC) have discovered a spatially modulating superconducting state in a new and unusual superconductor Uranium Ditelluride (UTe2). This new superconductor may provide a solution to one of quantum computing’s greatest challenges.
    Their finding has been published in the  journal Nature.
    Lead author Joe Carroll, a PhD researcher working with UCC Prof. of Quantum Physics Séamus Davis, explains the subject of the paper.
    “Superconductors are amazing materials which have many strange and unusual properties. Most famously they allow electricity to flow with zero resistance. That is, if you pass a current through them they don’t start to heat up, in fact, they don’t dissipate any energy despite carrying a huge current. They can do this because instead of individual electrons moving through the metal we have pairs of electrons which bind together. These pairs of electrons together form macroscopic quantum mechanical fluid.”
    “What our team found was that some of the electron pairs form a new crystal structure embedded in this background fluid. These types of states were first discovered by our group in 2016 and are now called Electron Pair-Density Waves. These Pair Density Waves are a new form of superconducting matter the properties of which we are still discovering.”
    “What is particularly exciting for us and the wider community is that UTe2 appears to be a new type of superconductor. Physicists have been searching for a material like it for nearly 40 years. The pairs of electrons appear to have intrinsic angular momentum. If this is true, then what we have detected is the first Pair-Density Wave composed of these exotic pairs of electrons.”

    When asked about the practical implications of this work Mr. Carroll explained:
    “There are indications that UTe2 is a special type of superconductor that could have huge consequences for quantum computing.”
    “Typical, classical, computers use bits to store and manipulate information. Quantum computers rely on quantum bits or qubits to do the same. The problem facing existing quantum computers is that each qubit must be in a superposition with two different energies — just as Schrödinger’s cat could be called both ‘dead’ and ‘alive’. This quantum state is very easily destroyed by collapsing into the lowest energy state — ‘dead’ — thereby cutting off any useful computation.
    “This places huge limits on the application of quantum computers. However, since its discovery five years ago there has been a huge amount of research on UTe2 with evidence pointing to it being a superconductor which may be used as a basis for topological quantum computing. In such materials there is no limit on the lifetime of the qubit during computation opening up many new ways for more stable and useful quantum computers. In fact, Microsoft have already invested billions of dollars into topological quantum computing so this is a well-established theoretical science already.” he said.
    “What the community has been searching for is a relevant topological superconductor; UTe2 appears to be that.”
    “What we’ve discovered then provides another piece to the puzzle of UTe2. To make applications using materials like this we must understand their fundamental superconducting properties. All of modern science moves step by step. We are delighted to have contributed to the understanding of a material which could bring us closer to much more practical quantum computers.”
    Congratulating the research team at the Macroscopic Quantum Matter Group Laboratory in University College Cork, Professor John F. Cryan, Vice President Research and Innovation said:
    “This important discovery will have significant consequences for the future of quantum computing. In the coming weeks, the University will launch UCC Futures — Future Quantum and Photonics and research led by Professor Seamus Davis and the Macroscopic Quantum Matter Group, with the use of one of the world’s most powerful microscopes, will play a crucial role in this exciting initiative.” More

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    Quantum computers could break the internet. Here’s how to save it

    Keeping secrets is hard. Kids know it. Celebrities know it. National security experts know it, too.

    And it’s about to get even harder.

    There’s always someone who wants to get at the juicy details we’d rather keep hidden. Yet at every moment, untold volumes of private information are zipping along internet cables and optical fibers. That information’s privacy relies on encryption, a way to mathematically scramble data to prevent any snoops from deciphering it — even with the help of powerful computers.

    But the mathematical basis of these techniques is under threat from a foe that has, until recently, seemed hypothetical: quantum computers.

    In the 1990s, scientists realized that these computers could exploit the weird physics of the minuscule realm of atoms and electrons to perform certain types of calculations out of reach for standard computers. That means that once the quantum machines are powerful enough, they could crack the mathematical padlocks on encrypted data, laying bare the world’s secrets.

    Today’s quantum computers are far too puny to defeat current security measures. But with more powerful quantum machines being regularly rolled out by the likes of IBM and Google, scientists, governments and others are beginning to take action. Experts are spreading the word that it’s time to prepare for a milestone some are calling Y2Q. That’s the year that quantum computers will gain the ability to crack the encoding schemes that keep electronic communications secure.

    “If that encryption is ever broken,” says mathematician Michele Mosca, “it would be a systemic catastrophe.”

    Y2Q is coming. What does it mean?

    Encryption pervades digital life — safeguarding emails, financial and medical data, online shopping transactions and more. Encryption is also woven into a plethora of physical devices that transmit information, from cars to robot vacuums to baby monitors. Encryption even secures infrastructure such as power grids. The tools Y2Q threatens are everywhere. “The stakes are just astronomically high,” says Mosca, of the University of Waterloo in Canada, who is also CEO of the cybersecurity company evolutionQ.

    The name Y2Q alludes to the infamous Y2K bug, which threatened to create computer havoc in the year 2000 because software typically used only two digits to mark the year (SN: 1/2/99, p. 4). Y2Q is a similarly systemic issue, but in many ways, it’s not a fair comparison. The fix for Y2Q is much more complex than changing how dates are represented, and computers are now even more inextricably entwined into society than two decades ago. Plus, no one knows when Y2Q will arrive.

    Confronted with the Y2Q threat, cryptography — the study and the practice of techniques used to encode information — is facing an overhaul. Scientists and mathematicians are now working urgently to prepare for that unknown date by devising new ways of encrypting data that won’t be susceptible to quantum decoding. An effort headed by the U.S. National Institute of Standards and Technology, or NIST, aims to release new standards for such post-quantum cryptography algorithms next year.

    Meanwhile, a longer-term effort takes a can’t-beat-’em-join-’em approach: using quantum technology to build a more secure, quantum internet. Scientists around the world are building networks that shuttle quantum information back and forth between cities, chasing the dream of communication that theoretically could be immune to hacking.

    How public-key cryptography works

    If you want to share a secret message with someone, you can encrypt it, garbling the information in such a way that it’s possible to decode it later.

    Schoolkids might do this with a simple cipher: For example, replace the letter A with the number 1, B with 2 and so on. Anyone who knows this secret key used to encrypt the message can later decode the message and read it — whether it’s the intended recipient or another sneaky classmate.

    It’s a simplified example of what’s called symmetric-key cryptography: The same key is used to encode and decode a message. In a more serious communication, the key would be much more complex — essentially impossible for anyone to guess. But in both cases, the same secret key is used to encode and decode.

    This strategy was used in cryptography for millennia, says computer scientist Peter Schwabe of the Max Planck Institute for Security and Privacy in Bochum, Germany. “It was either used in a military context or it was used between lovers that were not supposed to love each other.”

    But in the globally connected modern world, symmetric-key cryptography has a problem. How do you get the secret key to someone on the other side of the planet, someone you’ve never met, without anyone else getting their hands on it?

    To solve this quandary, in the 1970s cryptographers devised public-key cryptography, which uses special mathematical tricks to solve the symmetric-key conundrum. It uses two different, mathematically related keys. A public key is used to encrypt messages, and a mathematically related private key decodes them. Say Alice wants to send a message to Bob. She looks up his public key and uses it to scramble her communication. Only Bob, with his private key, can decode it. To any snoops that intercept the message, it’s meaningless.

    Public-key techniques are also used to create digital signatures. These signatures verify that someone online really is who they say they are, so you know you’re really downloading that new app from Apple, not some nefarious impersonator. Only the owner of a private key can sign the message, but anyone can use the public key to verify its authenticity.

    The public-key cryptography that permeates the internet is directly vulnerable to full-scale quantum computers. What’s more, symmetric-key cryptography often relies on public-key cryptography to share the secret key needed to communicate. That puts the majority of internet security under threat.

    Why quantum computers will threaten public-key cryptography

    If public-key encryption keeps your data hidden away under the floorboards, then to read that information, you need to build a way in. You have to be able to access the data with your private key. “There’s got to be a secret door somewhere in there, where if I knock the right way, it opens up,” Mosca says.

    Constructing such a trapdoor demands special mathematical tactics, based on operations that are easy to perform in one direction but hard in the opposite direction. Multiplying two prime numbers together is quick work for a computer, even if the numbers are very large. But it’s much more time-consuming for a computer to calculate the primes from their product. For large enough numbers, it’s impossible to do in a practical amount of time with a standard computer.

    The challenge of finding the prime factors of a large number is behind one of the main types of public-key encryption used today, known as RSA. A hacker using a classical computer wouldn’t be able to deduce the private key from the public key. Another math problem, known as the discrete logarithm problem, is a similar one-way street.

    These two mathematical problems underlie nearly all of the public-key cryptography in use today. But a sufficiently powerful quantum computer would blow their trapdoors wide open. “All of those public-key algorithms are vulnerable to an attack that can only be carried out by a quantum computer,” says mathematician Angela Robinson of NIST, in Gaithersburg, Md. “Our whole digital world is relying on quantum-vulnerable algorithms.”

    This vulnerability came to light in 1994, when mathematician Peter Shor, now at MIT, came up with an algorithm that would allow quantum computers to solve both of these math problems. In quantum machines, the bits, called qubits, can take on values of 0 and 1 simultaneously, a state known as a superposition. And qubits can be linked with one another through the quantum connection called entanglement, enabling new tactics like Shor’s (SN: 7/8/17 & 7/22/17, p. 34).

    “Back then, that was an interesting theoretical paper. Quantum computers were a distant dream,” says mathematician Dustin Moody of NIST, “but it wasn’t a practical threat.” Since then, there’s been a quantum computing boom (SN: 7/8/17 & 7/22/17, p. 28).

    The machines are being built using qubits made from various materials — from individual atoms to flecks of silicon to superconductors (which conduct electricity without resistance) — but all calculate according to quantum rules. IBM’s superconducting quantum computer Osprey, for example, has 433 qubits. That’s up from the five qubits of the computer IBM unveiled in 2016. The company plans to roll out one with more than a thousand qubits this year.

    That’s still far from the Y2Q threshold: To break RSA encryption, a quantum computer would need 20 million qubits, researchers reported in 2021 in Quantum.

    Mosca estimates that in the next 15 years, there’s about a 50 percent chance of a quantum computer powerful enough to break standard public-key encryption. That may seem like a long time, but experts estimate that previous major cryptography overhauls have taken around 15 years. “This is not a Tuesday patch,” Mosca says.

    The threat is even more pressing because the data we send today could be vulnerable to quantum computers that don’t exist yet. Hackers could harvest encrypted information now, and later decode it once a powerful quantum computer becomes available, Mosca says. “It’s just bad news if we don’t get ahead of this.”

    New algorithms could safeguard our security

    Getting ahead of the problem is the aim of Moody, Robinson and others who are part of NIST’s effort to select and standardize post-quantum encryption and digital signatures. Such techniques would have to thwart hackers using quantum machines, while still protecting from classical hacks.

    After NIST put out a call for post-quantum algorithms in 2016, the team received dozens of proposed schemes. The researchers sorted through the candidates, weighing considerations including the level of security provided and the computational resources needed for each. Finally, in July 2022, NIST announced four schemes that had risen to the top. Once the final standards for those algorithms are ready in 2024, organizations can begin making the post-quantum leap. Meanwhile, NIST continues to consider additional candidates.

    In parallel with NIST’s efforts, others are endorsing the post-quantum endeavor. In May 2022, the White House put out a memo setting 2035 as the goal for U.S. government agencies to go post-quantum. In November, Google announced it is already using post-quantum cryptography in internal communications.

    Several of the algorithms selected by NIST share a mathematical basis — a technique called lattice-based cryptography. It relies on a problem involving describing a lattice, or a grid of points, using a set of arrows, or vectors.

    In math, a lattice is described by a set of vectors used to produce it. Consider Manhattan. Even if you’d never seen a map of the city, you could roughly reproduce its grid using two arrows, one the length and direction of an avenue block and the other matching a street block. Discounting the city’s quirks, such as variations in block lengths, you’d just place arrows end-to-end until you’ve mapped out the whole grid.

    But there are more complicated sets of vectors that can reproduce the city’s grid. Picture two arrows starting, for example, at Washington Square Park in lower Manhattan, with one pointing to Times Square in Midtown and the other to a neighboring landmark, the Empire State Building. Properly chosen, two such vectors could also be used — with more difficulty — to map out the city’s grid.

    A math problem called the shortest vector problem asks: Given a set of long vectors that generate a lattice, what is the shortest vector that can be used as part of a set to produce the grid? If all you knew about the city was the location of those three landmarks, it’d be quite a task to back out the shortest vector corresponding to the city’s blocks.

    Now, picture doing that not for a 2-D map, but in hundreds of dimensions. That’s a problem thought to be so difficult that no computer, quantum or classical, could do it in a reasonable amount of time.

    The difficulty of that problem is what underlies the strength of several post-quantum cryptography algorithms. In lattice-based cryptography, a short vector is used to create the private key, and the long vectors produce the public key.

    Other post-quantum schemes NIST considered are based on different math problems. To choose among the options, NIST mathematicians’ chief consideration was the strength of each algorithm’s security. But none of these algorithms are definitively proved to be secure against quantum computers, or even classical ones. One algorithm originally considered by NIST, called SIKE, was later broken. It took just 10 minutes to crack on a standard computer, researchers reported in April in Advances in Cryptology – EUROCRYPT 2023.

    Although it might seem like a failure, the SIKE breakdown can be considered progress. The faith in the security of cryptographic algorithms comes from a trial by fire. “The more [that] smart people try to break something and fail, the more confidence we can get that it’s actually hard to break it,” Schwabe says. Some algorithms must perish in the process.

    A quantum internet could bolster security

    Quantum physics taketh away, but also, it gives. A different quantum technique can allow communication with mathematically proved security. That means a future quantum internet could, theoretically at least, be fully safe from both quantum and classical hacks.

    By transmitting photons — particles of light — and measuring their properties upon arrival, it’s possible to generate a shared private key that is verifiably safe from eavesdroppers.

    This quantum key distribution, or QKD, relies on a principle of quantum physics called the no-cloning theorem. Essentially, it’s impossible to copy quantum information. Any attempt to do so will alter the original information, revealing that someone was snooping. “Someone who was trying to learn that information would basically leave a fingerprint behind,” says quantum engineer Nolan Bitner of Argonne National Laboratory in Lemont, Ill.

    This quirk of quantum physics allows two people to share a secret key and, by comparing notes, determine whether the key has been intercepted along the way. If those comparisons don’t match as expected, someone was eavesdropping. The communicators discard their key and start over. If there is no sign of foul play, they can safely use their shared secret key to encrypt their communication and send it over the standard internet, certain of its security. It’s a quantum solution to the quandary of how two parties can share secret keys without ever meeting. There’s no need for a mathematical trapdoor that might be vulnerable to an undiscovered tactic.

    But QKD can’t be done over normal channels. It requires quantum networks, in which photons are created, sent zipping along optical fibers and are manipulated at the other end.

    Such networks already snake through select cities in the world. One threads through Chicago suburbs from the University of Chicago to Argonne lab and Fermilab in Batavia, for a total of 200 kilometers. In China, an extensive network connects cities along a more than 2,000-kilometer backbone that wends from Beijing to Shanghai, along with two quantum satellites that beam photons through the air. A quantum network crisscrosses South Korea, and another links several U.K. cities. There are networks in Tokyo and the Netherlands — the list goes on, with more to come.

    A quantum network in China extends more than 2,000 kilometers from Beijing to Shanghai and includes a quantum satellite that beams photons to ground stations in Xinglong and Nanshan. Other quantum networks are being built and tested around the world.Y.-A. CHEN ET AL/NATURE 2021, ADAPTED BY C. CHANG

    A quantum network in China extends more than 2,000 kilometers from Beijing to Shanghai and includes a quantum satellite that beams photons to ground stations in Xinglong and Nanshan. Other quantum networks are being built and tested around the world.Y.-A. CHEN ET AL/NATURE 2021, ADAPTED BY C. CHANG

    Many of these networks are test-beds used by researchers to study the technology outside of a lab. But some are getting real-world use. Banks use China’s network, and South Korea’s links government agencies. Companies such as ID Quantique, based in Switzerland, offer commercial QKD devices.

    QKD’s security is mathematically proven, but quantum networks can fall short of that guarantee in practice. The difficulty of creating, transmitting, detecting and storing quantum particles can open loopholes. Devices and networks must be painstakingly designed and tested to ensure a hacker can’t game the system.

    And one missing component in particular is holding quantum networks back. “The number one device is quantum memory,” says quantum physicist Xiongfeng Ma of Tsinghua University in Beijing. When sending quantum information over long distances through fibers, particles can easily get lost along the way. For distances greater than about 100 kilometers, that makes quantum communication impractical without the use of way stations that amplify the signal. Such way stations temporarily convert data into classical, rather than quantum, information. That classical step means hackers could target these “trusted nodes” undetected, marring QKD’s pristine security. And it limits what quantum maneuvers the networks can do.

    It’s not possible to create pairs of particles that are entangled over long distances in a network like this. But special stations sprinkled throughout the network, called quantum repeaters, could solve the problem by storing information in a quantum memory. To create far-flung entangled particles, scientists could first entangle sets of particles over short distances, storing them in quantum memories at each quantum repeater. Performing certain operations on the entangled particles could leapfrog that entanglement to other particles farther apart. By repeating this process, particles could be entangled across extended distances.

    But, thanks in part to quantum particles’ tendency to be easily perturbed by outside influences, scientists have yet to develop a practical quantum repeater. “When that does appear, it’s likely to catalyze global quantum networks,” says David Awschalom, a physicist at the University of Chicago. Not only will such technologies allow longer distances and better security for QKD, but they will also enable more complicated tasks, like entangling distant quantum computers to allow them to work together.

    A European effort called the Quantum Internet Alliance aims to build a network with quantum repeaters by the end of 2029, creating a backbone stretching over 500 kilometers, in addition to two metropolitan-scale networks. The effort is “super challenging,” says physicist and computer scientist Stephanie Wehner of Delft University of Technology in the Netherlands. “We are on a moon shot mission.” Eventually, scientists envision a global quantum internet.

    Awschalom imagines the networks becoming accessible to all. “Wouldn’t it be great to be able to go to a public library and be able to get onto a quantum network?”

    A link between a ground station (red and green lasers shown in this time-lapse image) and the quantum satellite Micius shows the potential for long-distance secure communications. The satellite beams photons to the ground station, in Xinglong, China.JIN LIWANG/XINHUA/ALAMY LIVE NEWS

    What does the future of cryptography look like?

    QKD and post-quantum cryptography are complementary. “In order to overcome the threat of the quantum computers we need both,” says physicist Nicolas Gisin of the University of Geneva and cofounder of ID Quantique. When people are exchanging information that doesn’t require the utmost security — say, using a mobile phone to post cat memes on Reddit — post-quantum cryptography will be more practical, as it doesn’t demand a to-and-fro of individual quantum particles. But “there are really situations where we want to make sure that the security is going to last … for several decades, and post-quantum cryptography cannot guarantee that,” Gisin says.

    Eventually, quantum techniques could allow for even more advanced types of security, such as blind quantum computing. In that scheme, a user could compute something on a remote quantum computer without anyone being able to determine what they’re computing. A technique called covert quantum communication would allow users to communicate securely while hiding that they were exchanging messages at all. And device-independent QKD would ensure security even if the devices used to communicate are potentially flawed (SN: 8/27/22, p. 10).

    The appeal of such extreme secrecy, of course, depends upon whether you’re the secret-keeper or the snoop. In the United States, government agencies like the FBI, CIA and the National Security Agency have argued that encryption makes it difficult to eavesdrop on criminals or terrorists. The agencies have a history of advocating for back doors that would let them in on encrypted communications — or building in secret back doors.

    But quantum techniques, done properly, can prevent anyone from intercepting secrets, even powerful government agencies.

    “It’s interesting to think about a world where, in principle, one might imagine perfect security,” Awschalom says. “Is that a good thing or is that a bad thing?” More

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    Boy fly meets girl fly meets AI: Training an AI to recognize fly mating identifies a gene for mating positions

    A research group at the Graduate School of Science, Nagoya University in Japan has used artificial intelligence to determine that Piezo, a channel that receives mechanical stimuli, plays a role in controlling the mating posture of male fruit flies (Drosophila melanogaster). Inhibition of Piezo led the flies to adopt an ineffective mating posture that decreased their reproductive performance. Their findings were reported in iScience.
    Most previous studies of animal mating have been limited to behavioral studies, limiting our understanding of this essential process. Since many animals adopt a fixed posture during copulation, maintaining an effective mating position is vital for reproductive success. In fruit flies, the male mounts the female and maintains this posture for at least until he transfers sufficient sperm to fertilize the female, which occurs about 8 minutes after copulation initiation. The Nagoya University research group realized that some factor was involved in maintaining this copulation posture.
    A likely contender is Piezo. Piezo is a family of transmembrane proteins found in bristle cells, the sensitive cells in male genitals. Piezo is activated when a mechanical force is applied to a cell membrane, allowing ions to flow through the channel and generate an electrical signal. This signal triggers cellular responses, including the release of neurotransmitters in neurons and the contraction of muscle cells. Such feedback helps a fly maintain his mating position.
    After identifying that the piezo gene is involved in the mating of fruit flies, Professor Azusa Kamikouchi (she/her), Assistant Professor Ryoya Tanaka (he/him), and student Hayato M. Yamanouchi (he/him) used optogenetics to further explore the neural mechanism of this phenomenon. This technique combines genetic engineering and optical science to create genetically modified neurons that can be inactivated with light of specific wavelengths. When the light was turned on during mating, the neuron was silenced. This allowed the researchers to manipulate the activity of piezo-expressing neurons.
    “This step proved to be a big challenge for us,” Kamikouchi said. “Using optogenetics, specific neurons are silenced only when exposed to photostimulation. However, our interest was silencing neural activity during copulation. Therefore, we had to make sure that the light was only turned on during mating. However, if the experimenter manually turned the photostimulation on in response to the animal’s copulation, they needed to observe the animal throughout the experiment. Waiting around for fruit flies to mate is incredibly time-consuming.”
    The observation problem led the group to establish an experimental deep learning system that could recognize copulation. By training the AI to recognize when sexual intercourse was occurring, they could automatically control photostimulation. This allowed them to discover that when piezo-expressing neurons were inhibited, males adopted a wonky, largely ineffective mating posture. As one might expect, the males that showed difficulty in adopting an appropriate sexual position had fewer offspring. They concluded that a key role of the piezo gene was helping the male shift his axis in response to the female for maximum mating success.
    “Piezo proteins have been implicated in a variety of physiological processes, including touch sensation, hearing, blood pressure regulation, and bladder function,” said Kamikouchi. “Now our findings suggest that reproduction can be added to the list. Since mating is an important behavior for reproduction that is widely conserved in animals, understanding its control mechanism will lead to a greater understanding of the reproductive system of animals in general.”
    Kamikouchi is enthusiastic about the use of AI in such research. “With the recent development of informatics, experimental systems and analysis methods have advanced dramatically,” she concludes. “In this research, we have succeeded in creating a device that automatically detects mating using machine learning-based real-time analysis and controls photostimulation necessary for optogenetics. To investigate the neural mechanisms that control animal behavior, it is important to conduct experiments in which neural activity is manipulated only when an individual exhibits a specific behavior. The method established in this study can be applied not only to the study of mating in fruit flies but also to various behaviors in other animals. It should make a significant contribution to the promotion of neurobiological research.” More

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    How the brain processes numbers — New procedure improves measurement of human brain activity

    Measuring human brain activity down to the cellular level: until now, this has been possible only to a limited extent. With a new approach developed by researchers at the Technical University of Munich (TUM), it will now be much easier. The method relies on microelectrodes along with the support of brain tumor patients, who participate in studies while undergoing “awake” brain surgery. This enabled the team to identify how our brain processes numbers.
    We use numbers every day. It happens in a very concrete way when we count objects. And it happens abstractly, for example when we see the symbol “8” or do complex calculations.
    In a study published in the journal Cell Reports, a team of researchers and clinicians working with Simon Jacob, Professor of Translational Neurotechnology at the Department of Neurosurgery at TUM’s university hospital Klinikum rechts der Isar, was able to show how the brain processes numbers. The researchers found that individual neurons in the brains of participants were specialized in handling specific numbers. Each one of these neurons was particularly active when its “preferred” number of elements in a dot pattern was presented to the patient. To a somewhat lesser degree this was also the case when the subjects processed number symbols.
    “We already knew that animals processed numbers of objects in this way,” says Prof. Jacob. “But until now, it was not possible to demonstrate conclusively how it works in humans. This has brought us a step closer to unravelling the mechanisms of cognitive functions and developing solutions when things go wrong with these brain functions, for example.”
    Recording individual neurons is a challenge
    To get to this result, Prof. Jacob and his team first had to solve a fundamental problem. “The brain functions by means of electrical impulses,” says Simon Jacob. “So it is by detecting these signals directly that we can learn the most about cognition and perception.”
    There are, however, few opportunities for direct measurements of human brain activity. Neurons cannot be individually recorded through the skull. Some medical teams surgically implant electrodes in epilepsy patients. However, these procedures do not reach the brain region believed to be responsible for processing numbers.

    Innovative advancement of established approaches
    Simon Jacob and an interdisciplinary team therefore developed an approach that adapts established technologies and opens up entirely new possibilities in neuroscience. At the heart of the procedure are microelectrode arrays that have undergone extensive testing in animal studies.
    To ensure that the electrodes would produce reliable data in awake surgeries on the human brain, the researchers had to reconfigure them in close collaboration with the manufacturer. The trick was to increase the distance between the needle-like sensors used to record the electrical activities of a cell. “In theory, tightly packed electrodes will produce more data,” says Simon Jacob. “But in practice the large number of contacts stuns the implanted brain region, so that no usable data are recorded.”
    Patients support research
    The development of the procedure was possible only because patients with brain tumors agreed to support the research team. While undergoing brain surgery, they permitted sensors to be implanted and performed test tasks for the researchers. According to Simon Jacob, the experimental procedures did not negatively affect the work of the surgical team.
    A greater number of medical centers can conduct studies
    “Our procedure has two key advantages,” says Simon Jacob. First, such tumor surgeries provide access to a much larger area of the brain. “And second, with the electrodes we used, which have been standardized and tested in years of animal trials, many more medical centers will be able to measure neuronal activity in the future” says Jacob. While epilepsy operations are performed only at a small number of centers and on relatively few patients, he explains, many more university hospitals perform awake operations on patients with brain tumors. “With a significantly larger number of studies with standardized methods and sensors, we can learn a lot more in the coming years about how the human brain functions,” says Simon Jacob. More

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    Emulating how krill swim to build a robotic platform for ocean navigation

    Picture a network of interconnected, autonomous robots working together in a coordinated dance to navigate the pitch-black surroundings of the ocean while carrying out scientific surveys or search-and-rescue missions.
    In a new study published in Scientific Reports, a team led by Brown University researchers has presented important first steps in building these types of underwater navigation robots. In the study, the researchers outline the design of a small robotic platform called Pleobot that can serve as both a tool to help researchers understand the krill-like swimming method and as a foundation for building small, highly maneuverable underwater robots.
    Pleobot is currently made of three articulated sections that replicate krill-like swimming called metachronal swimming. To design Pleobot, the researchers took inspiration from krill, which are remarkable aquatic athletes and display mastery in swimming, accelerating, braking and turning. They demonstrate in the study the capabilities of Pleobot to emulate the legs of swimming krill and provide new insights on the fluid-structure interactions needed to sustain steady forward swimming in krill.
    According to the study, Pleobot has the potential to allow the scientific community to understand how to take advantage of 100 million years of evolution to engineer better robots for ocean navigation.
    “Experiments with organisms are challenging and unpredictable,” said Sara Oliveira Santos, a Ph.D. candidate at Brown’s School of Engineering and lead author of the new study. “Pleobot allows us unparalleled resolution and control to investigate all the aspects of krill-like swimming that help it excel at maneuvering underwater. Our goal was to design a comprehensive tool to understand krill-like swimming, which meant including all the details that make krill such athletic swimmers.”
    The effort is a collaboration between Brown researchers in the lab of Assistant Professor of Engineering Monica Martinez Wilhelmus and scientists in the lab of Francisco Cuenca-Jimenez at the Universidad Nacional Autónoma de México.

    A major aim of the project is to understand how metachronal swimmers, like krill, manage to function in complex marine environments and perform massive vertical migrations of over 1,000 meters — equivalent to stacking three Empire State Buildings — twice daily.
    “We have snapshots of the mechanisms they use to swim efficiently, but we do not have comprehensive data,” said Nils Tack, a postdoctoral associate in the Wilhelmus lab. “We built and programmed a robot that precisely emulates the essential movements of the legs to produce specific motions and change the shape of the appendages. This allows us to study different configurations to take measurements and make comparisons that are otherwise unobtainable with live animals.”
    The metachronal swimming technique can lead to remarkable maneuverability that krill frequently display through the sequential deployment of their swimming legs in a back to front wave-like motion. The researchers believe that in the future, deployable swarm systems can be used to map Earth’s oceans, participate in search-and-recovery missions by covering large areas, or be sent to moons in the solar system, such as Europa, to explore their oceans.
    “Krill aggregations are an excellent example of swarms in nature: they are composed of organisms with a streamlined body, traveling up to one kilometer each way, with excellent underwater maneuverability,” Wilhelmus said. “This study is the starting point of our long-term research aim of developing the next generation of autonomous underwater sensing vehicles. Being able to understand fluid-structure interactions at the appendage level will allow us to make informed decisions about future designs.”
    The researchers can actively control the two leg segments and have passive control of Pleobot’s biramous fins. This is believed to be the first platform that replicates the opening and closing motion of these fins. The construction of the robotic platform was a multi-year project, involving a multi-disciplinary team in fluid mechanics, biology and mechatronics.

    The researchers built their model at 10 times the scale of krill, which are usually about the size of a paperclip. The platform is primarily made of 3D printable parts and the design is open-access, allowing other teams to use Pleobot to continue answering questions on metachronal swimming not just for krill but for other organisms like lobsters.
    In the published study, the group reveals the answer to one of the many unknown mechanisms of krill swimming: how they generate lift in order not to sink while swimming forward. If krill are not swimming constantly, they will start sinking because they are a little heavier than water. To avoid this, they still have to create some lift even while swimming forward to be able to remain at that same height in the water, said Oliveira Santos.
    “We were able to uncover that mechanism by using the robot,” said Yunxing Su, a postdoctoral associate in the lab. “We identified an important effect of a low-pressure region at the back side of the swimming legs that contributes to the lift force enhancement during the power stroke of the moving legs.”
    In the coming years, the researchers hope to build on this initial success and further build and test the designs presented in the article. The team is currently working to integrate morphological characteristics of shrimp into the robotic platform, such as flexibility and bristles around the appendages.
    The work was partially funded by a NASA Rhode Island EPSCoR Seed Grant. More

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    Researchers make a quantum computing leap with a magnetic twist

    Quantum computing could revolutionize our world. For specific and crucial tasks, it promises to be exponentially faster than the zero-or-one binary technology that underlies today’s machines, from supercomputers in laboratories to smartphones in our pockets. But developing quantum computers hinges on building a stable network of qubits — or quantum bits — to store information, access it and perform computations.
    Yet the qubit platforms unveiled to date have a common problem: They tend to be delicate and vulnerable to outside disturbances. Even a stray photon can cause trouble. Developing fault-tolerant qubits — which would be immune to external perturbations — could be the ultimate solution to this challenge.
    A team led by scientists and engineers at the University of Washington has announced a significant advancement in this quest. In a pair of papers published June 14 in Nature and June 22 in Science, they report that, in experiments with flakes of semiconductor materials — each only a single layer of atoms thick — they detected signatures of “fractional quantum anomalous Hall” (FQAH) states. The team’s discoveries mark a first and promising step in constructing a type of fault-tolerant qubit because FQAH states can host anyons — strange “quasiparticles” that have only a fraction of an electron’s charge. Some types of anyons can be used to make what are called “topologically protected” qubits, which are stable against any small, local disturbances.
    “This really establishes a new paradigm for studying quantum physics with fractional excitations in the future,” said Xiaodong Xu, the lead researcher behind these discoveries, who is also the Boeing Distinguished Professor of Physics and a professor of materials science and engineering at the UW.
    FQAH states are related to the fractional quantum Hall state, an exotic phase of matter that exists in two-dimensional systems. In these states, electrical conductivity is constrained to precise fractions of a constant known as the conductance quantum. But fractional quantum Hall systems typically require massive magnetic fields to keep them stable, making them impractical for applications in quantum computing. The FQAH state has no such requirement — it is stable even “at zero magnetic field,” according to the team.
    Hosting such an exotic phase of matter required the researchers to build an artificial lattice with exotic properties. They stacked two atomically thin flakes of the semiconductor material molybdenum ditelluride (MoTe2) at small, mutual “twist” angles relative to one another. This configuration formed a synthetic “honeycomb lattice” for electrons. When researchers cooled the stacked slices to a few degrees above absolute zero, an intrinsic magnetism arose in the system. The intrinsic magnetism takes the place of the strong magnetic field typically required for the fractional quantum Hall state. Using lasers as probes, the researchers detected signatures of the FQAH effect, a major step forward in unlocking the power of anyons for quantum computing.

    The team — which also includes scientists at the University of Hong Kong, the National Institute for Materials Science in Japan, Boston College and the Massachusetts Institute of Technology — envisions their system as a powerful platform to develop a deeper understanding of anyons, which have very different properties from everyday particles like electrons. Anyons are quasiparticles — or particle-like “excitations” — that can act as fractions of an electron. In future work with their experimental system, the researchers hope to discover an even more exotic version of this type of quasiparticle: “non-Abelian” anyons, which could be used as topological qubits. Wrapping — or “braiding” — the non-Abelian anyons around each other can generate an entangled quantum state. In this quantum state, information is essentially “spread out” over the entire system and resistant to local disturbances — forming the basis of topological qubits and a major advancement over the capabilities of current quantum computers.
    “This type of topological qubit would be fundamentally different from those that can be created now,” said UW physics doctoral student Eric Anderson, who is lead author of the Science paper and co-lead author of the Nature paper. “The strange behavior of non-Abelian anyons would make them much more robust as a quantum computing platform.”
    Three key properties, all of which existed simultaneously in the researchers’ experimental setup, allowed FQAH states to emerge: Magnetism: Though MoTe2 is not a magnetic material, when they loaded the system with positive charges, a “spontaneous spin order” — a form of magnetism called ferromagnetism — emerged. Topology: Electrical charges within their system have “twisted bands,” similar to a Möbius strip, which helps make the system topological. Interactions: The charges within their experimental system interact strongly enough to stabilize the FQAH state.The team hopes that, using their approach, non-Abelian anyons await for discovery.
    “The observed signatures of the fractional quantum anomalous Hall effect are inspiring,” said UW physics doctoral student Jiaqi Cai, co-lead author on the Nature paper and co-author of the Science paper. “The fruitful quantum states in the system can be a laboratory-on-a-chip for discovering new physics in two dimensions, and also new devices for quantum applications.”
    “Our work provides clear evidence of the long-sought FQAH states,” said Xu, who is also a member of the Molecular Engineering and Sciences Institute, the Institute for Nano-Engineered Systems and the Clean Energy Institute, all at UW. “We are currently working on electrical transport measurements, which could provide direct and unambiguous evidence of fractional excitations at zero magnetic field.”
    The team believes that, with their approach, investigating and manipulating these unusual FQAH states can become commonplace — accelerating the quantum computing journey.
    Additional co-authors on the papers are William Holtzmann and Yinong Zhang in the UW Department of Physics; Di Xiao, Chong Wang, Xiaowei Zhang, Xiaoyu Liu and Ting Cao in the UW Department of Materials Science & Engineering; Feng-Ren Fan and Wang Yao at the University of Hong Kong and the Joint Institute of Theoretical and Computational Physics at Hong Kong; Takashi Taniguchi and Kenji Watanabe from the National Institute of Materials Science in Japan; Ying Ran of Boston College; and Liang Fu at MIT. The research was funded by the U.S. Department of Energy, the Air Force Office of Scientific Research, the National Science Foundation, the Research Grants Council of Hong Kong, the Croucher Foundation, the Tencent Foundation, the Japan Society for the Promotion of Science and the University of Washington. More

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    How secure are voice authentication systems really?

    Computer scientists at the University of Waterloo have discovered a method of attack that can successfully bypass voice authentication security systems with up to a 99% success rate after only six tries.
    Voice authentication — which allows companies to verify the identity of their clients via a supposedly unique “voiceprint” — has increasingly been used in remote banking, call centers and other security-critical scenarios.
    “When enrolling in voice authentication, you are asked to repeat a certain phrase in your own voice. The system then extracts a unique vocal signature (voiceprint) from this provided phrase and stores it on a server,” said Andre Kassis, a Computer Security and Privacy PhD candidate and the lead author of a study detailing the research.
    “For future authentication attempts, you are asked to repeat a different phrase and the features extracted from it are compared to the voiceprint you have saved in the system to determine whether access should be granted.”
    After the concept of voiceprints was introduced, malicious actors quickly realized they could use machine learning-enabled “deepfake” software to generate convincing copies of a victim’s voice using as little as five minutes of recorded audio.
    In response, developers introduced “spoofing countermeasures” — checks that could examine a speech sample and determine whether it was created by a human or a machine.
    The Waterloo researchers have developed a method that evades spoofing countermeasures and can fool most voice authentication systems within six attempts. They identified the markers in deepfake audio that betray it is computer-generated, and wrote a program that removes these markers, making it indistinguishable from authentic audio.
    In a recent test against Amazon Connect’s voice authentication system, they achieved a 10 per cent success rate in one four-second attack, with this rate rising to over 40 per cent in less than thirty seconds. With some of the less sophisticated voice authentication systems they targeted, they achieved a 99 per cent success rate after six attempts.
    Kassis contends that while voice authentication is obviously better than no additional security, the existing spoofing countermeasures are critically flawed.
    “The only way to create a secure system is to think like an attacker. If you don’t, then you’re just waiting to be attacked,” Kassis said.
    Kassis’ supervisor, computer science professor Urs Hengartner added, “By demonstrating the insecurity of voice authentication, we hope that companies relying on voice authentication as their only authentication factor will consider deploying additional or stronger authentication measures.” More