But like all superpowers, they will have their limits
Category: computing – Page 9
Researchers Simulate Alzheimer’s Progression Across the Entire Brain
This hypothesis has led to a new “whole-brain” mathematical and computational model developed at the MOX Laboratory of the Department of Mathematics of Politecnico di Milano. The model is designed to describe in an integrated way the interaction between the spread of amyloid beta and the functioning of the cerebral vascular network. The aim is to provide a tool capable of simulating, on the scale of the whole organ, how small biological or vascular alterations can evolve over time and contribute to neurodegeneration. The model and the accompanying scientific study have been published in the prestigious scientific journal Computer Methods in Applied Mechanics and Engineering.
The model integrates two scales of analysis. On the one hand, it describes the dynamics of the production, transformation, diffusion and elimination of the healthy and pathological forms of amyloid beta. On the other, it describes blood flow through a “macroscopic” description of arteries, capillaries and veins, treating brain tissue as a porous medium perfused by blood vessels, through a macroscopic compartmental model. The two components are then connected to represent the possible mechanism of mutual reinforcement between protein accumulation and vascular dysfunction.
The simulations show a particularly relevant result: the brain can evolve into different states depending on the initial conditions. Small localised amounts of amyloid beta can be eliminated, allowing the system to return to a healthy state. Conversely, larger amounts can trigger a self-sustained spread of the pathology at brain scale.
Photonic time crystals unlock ultrafast control of light in the terahertz range
An international team of researchers from École Polytechnique, Collège de France and Helmholtz-Zentrum Dresden-Rossendorf (HZDR) has achieved a world first: the experimental realization of an all-optical photonic time crystal (PTC), a material whose optical properties can be strongly and periodically modulated over ultrafast timescales.
Published in Nature, this breakthrough uses HZDR’s TELBE superradiant terahertz source to drive the system into a new regime of light-matter interaction in the terahertz range. This discovery paves the way for ultrafast optical computing, new telecommunications systems and eventually new types of terahertz lasers.
Shaping the properties of light as it interacts with materials is the foundation of many discoveries and technological advances, including optical fibers for telecommunications, lasers as light sources and sensors for chemistry and biology.
One LED produces four stable colors at room temperature
Full-color displays normally require separate red, green and blue light emitters. A team from the University of Osaka and Ritsumeikan University has demonstrated another approach: a single light-emitting layer that produces several colors when electrically powered at room temperature. The study was published in Applied Physics Letters.
Micro-LED displays promise high brightness, energy efficiency and resolution. However, conventional green and red nitride LEDs can show changes in color as the current increases. Producing several colors also generally requires multiple light-emitting layers or separately manufactured chips, making it difficult to place many pixels into a very small area.
The team used a manufacturing method already widely employed for nitride LEDs to create aluminum gallium nitride LEDs containing terbium ions.
Quantum in the palm of your hand: The evolution of superconducting qubits
Electrons zipping through transistors, powering the screens on our smartphones. Light zooming from distant stars to Earth, moving faster than anything else in the universe. Protons enabling MRI machines to analyze people’s injuries.
Quantum mechanics explains the behavior of subatomic particles like electrons, photons and protons. In contrast to classical physics that we can observe with our senses, particles in the quantum realm have unusual behaviors. Even though quantum particles make common technologies possible, we don’t experience these behaviors in our everyday world.
That’s why a discovery in 1985 was such a big deal. In a laboratory at the University of California, Berkeley, a team of three scientists showed that a system you could see could demonstrate quantum behavior. Or as they said in one of the journal articles covering the experiments, the system was “big enough to get one’s grubby fingers on.”
Pulling Graphite Out of Thin Air
Graphite, the carbon center of your humble #2 pencil, is also an essential component in technologies such as batteries, smartphones, laptops, and industrial power equipment. Today, nearly all of this critical mineral has to be mined and processed and, in the United States, imported.
But now, researchers at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), UC Berkeley, and Estonia’s National Institute of Chemical Physics and Biophysics have shown a promising way to convert waste carbon pulled from the air into graphite, opening up a potential alternative to mining. The work was published recently in the journal Nature Communications.
Researchers built a custom microscope setup to watch a process known as molten-salt electrolysis, which uses electricity and hot liquid salts to turn carbon dioxide into solid carbon. For the first time, researchers were able to watch the process in real time inside the corrosive, 500-degree-Celsius molten salts while the system was running.
Tiny infrared chip could improve detection of gases and heat
Infrared cameras can be used to spot useful information that our eyes can’t see, such as gases escaping from a pipeline, chemicals in the atmosphere, or heat leaking from a building. But sensing infrared light in sophisticated ways still requires expensive and bulky systems.
Now MIT researchers have created a chip-based optical device that can dynamically control incoming infrared light, to act as a tunable lens that gathers additional information for infrared cameras. Each microscopic pixel of the device’s lens can control infrared light independently, allowing it to change its focus and help cameras detect different signals without moving parts.
The system is described in a paper published in Nature Communications. The researchers also explain how they built a lab-scale demonstration using mostly conventional manufacturing processes in a semiconductor chip factory, suggesting the approach could be implemented at industrial scales.