How might AI change the way we advance human knowledge? Could it change how universities like Cambridge carry out one of their core functions: research? Could AI be a technological transformation unlike anything we’ve seen before?
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Noninvasive stent imaging powered by light and sound
In a new study, researchers show, for the first time, that photoacoustic microscopy can image stents through skin, potentially offering a safer, easier way to monitor these life-saving devices. Each year, around 2 million people in the U.S. are implanted with a stent to improve blood flow in narrowed or blocked arteries.
“It is critical to monitor stents for problems such as fractures or improper positioning, but conventionally used techniques require invasive procedures or radiation exposure,” said co-lead researcher Myeongsu Seong from Xi’an Jiaotong-Liverpool University in China. “This inspired us to test the potential of using photoacoustic imaging for monitoring stents through the skin.”
In the journal Optics Letters, the researchers show that photoacoustic microscopy can be used to visualize stents covered with mouse skin under various clinically relevant conditions, including simulated damage and plaque buildup.
Good vibrations: Scientists use imaging technology to visualize heat
Most people envision vibration on a large scale, like the buzz of a cell phone notification or the oscillation of an electric toothbrush. But scientists think about vibration on a smaller scale—atomic, even.
In a first for the field, researchers from The Grainger College of Engineering at the University of Illinois at Urbana-Champaign have used advanced imaging technology to directly observe a previously hidden branch of vibrational physics in 2D materials. Their findings, published in Science, confirm the existence of a previously unseen class of vibrational modes and present the highest resolution images ever taken of a single atom.
Two-dimensional materials are a promising candidate for next-generation electronics because they can be scaled down in size to thicknesses of just a few atoms while maintaining desirable electronic properties. A route to these new electronic devices lies at the atomic level, by creating so-called Moiré systems—stacks of 2D materials whose lattices do not match, for reasons such as the twisting of atomic layers.
Neuromorphic ionic computing in droplet interface synapses
Droplet interface bilayer was formed between two aqueous droplets immersed in hexadecane oil and lined with a lipid monolayer using the “lipid in” technique. First, to prepare the ~100-nm-diameter DPhPC large unilamellar vesicles (LUVs), 2 mg of DPhPC lipids dissolved in chloroform was placed into a glass vial. For different bilayer compositions, the total amount of DPhPC, cholesterol, and SM was kept at 2 mg while varying their mass ratios. The solvent was evaporated under an air stream and further dried overnight in a vacuum desiccator. Then, 1 ml of buffer was added to the desiccated lipid film to achieve a final lipid concentration of 2 mg/ml after a 30-s bath sonication. Unless otherwise noted, the buffer solutions in the droplets were 100 mM KCl, 10 mM tris, and 1 mM EDTA at pH 7.5. The mixtures were incubated at ambient temperature for 30 min. To form unilamellar vesicles, the samples underwent 7 freeze-thaw cycles, involving rapid freezing in liquid nitrogen and subsequent thawing at 50°C. The samples were then extruded through 100-nm pore-sized polycarbonate membranes 21 times using a mini-extruder (Avanti Polar Lipids).
Next, two 100-μm-diameter Ag/AgCl electrodes with ball-ended tips were made hydrophilic by coating with low-melt agarose in KCl buffer (3%, w/v). The electrodes were affixed to micromanipulators (NMN-21, Narishige) mounted onto an inverted optical microscope (Leica DMi1) and connected to a patch-clamp amplifier headstage input and ground. Approximately 600-nl droplets of LUV solution were carefully placed on the electrodes in the hexadecane oil bath using a micropipette. For reconstitution of α-HL in the bilayer, a diluted α-HL stock solution (0.5 mg/ml reduced to 1 μg/ml) was added to the LUV solution before droplet formation.
The droplets were incubated for at least 5 min to allow the formation of a self-assembled lipid monolayer. During this process, the droplets sagged slightly away from the electrode, becoming relatively free from strong electrode adhesion. Subsequently, the droplets were gently brought together to form a bilayer at the interface, which was confirmed by optical microscopy imaging and membrane capacitance measurements under an applied triangular voltage wave. The relative freedom of the droplets from the electrode ensures that the electrode-droplet interfaces do not interfere with the bilayer geometry or its structural response under the applied voltages (movie S1).
Protein Core Stability Rules Open Door for Faster Protein Design
Interestingly, the model remained accurate despite the diversity of natural domains and the divergence over such a long time span—some domains sharing less than 25% of their sequences between species.
“Evolution didn’t have to sift through an entire universe of sequences. Instead, the biochemical laws of folding create a vast, forgiving landscape for natural selection,” said Escobedo.
The field of protein engineering and design often relies on the concept that making small incremental changes to structure, followed by experimentally screening variants, is necessary. However, with the increasing use of machine learning and AI, this expectation is increasingly being pushed aside. The present work suggests that while not all proteins with significant core changes are functional, large-scale redesigns, including changes to core domains, may retain stability, challenging assumptions that such regions are off-limits.
Researchers uncover a topological excitonic insulator with a tunable momentum order
Topological materials are a class of materials that exhibit unique electronic properties at their boundary (surface in 3D materials; edge in 2D materials) that are robust against imperfections or disturbances and are markedly different from their bulk properties. In other words, these materials could be insulators (i.e., resisting the flow of electrons or heat), and yet be conducting at their boundary (i.e., allowing electrons or heat to easily flow through them).
Meta’s wristband breakthrough lets you use digital devices without touching them
Could Meta be on the verge of transforming how we interact with our digital devices? If the company’s latest innovation takes off, we might soon be controlling our computers, cell phones and tablets with a simple flick of the wrist.
Researchers at Meta’s Reality Labs division have unveiled an experimental wristband that translates hand gestures and subtle finger movements into commands that interact with a computer. This allows a user to push a cursor around a screen or open an app without needing a mouse, touchscreen or keyboard. The technology can even transcribe handwriting in the air into text (currently at a speed of 20.9 words per minute).
In a paper published in Nature, the team describes how its sEMG-RD (surface electromyography research) works. The wristband uses a technique called electromyography to pick up electrical signals when the brain tells the hand to perform an action. It then converts those signals into commands that control a connected device, such as your phone.