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May 24, 2024

Time-Symmetric Motion Maximizes Energy Efficiency in Fluid

Posted by in categories: biotech/medical, nanotechnology

Researchers discovered a trick for dragging an object in a fluid with minimal effort, suggesting an optimal strategy for nanorobots.

A research team has demonstrated that the most efficient protocol for dragging a microscopic object through a fluid has an unexpected feature: the variation of the velocity with time after the midpoint of the trip is the reverse of its variation up to the midpoint [1]. This time-symmetry property, the researchers say, can help to identify the most efficient control strategy in a wide variety of micromechanical systems and could improve the operation of tiny machines.

Biomedical engineers are exploring micro-and nanoscale devices that swim through the body under their own power to deliver drugs [2]. Machine-like motion at tiny scales is also common in biology, for instance in the transport of compartments called vesicles by motor proteins inside cells [3]. To understand the energetics of such systems, Sarah Loos of the University of Cambridge and colleagues have studied a simple model of microscale transport. They used optical tweezers—a laser beam that can trap a small particle—to drag a 2.7-micrometer-diameter silica sphere through fluids. “This problem is simple enough to be solved analytically and realized experimentally, yet rich enough to show some fundamental characteristics of optimal control in complex systems,” says Loos. In practice, the device inducing the motion “could be a nanorobot carrying a drug molecule or a molecular motor that pulls or pushes against a microscopic object.”

May 24, 2024

Cosmic Strings’ Imprints in High-Frequency Gravitational Waves

Posted by in category: physics

Spacetime wrinkles known as cosmic strings, which might have formed in the early Universe, could be a dominant source of gravitational waves at ultrahigh frequencies, according to new calculations.

May 24, 2024

Ultrablack Coating Could Reduce Stray Light in Telescopes

Posted by in category: futurism

Using atomic layer deposition, scientists have created a new light-absorbing thin film that could help telescopes see a starrier night.

May 24, 2024

Solar Composition Altered by Plasma Waves

Posted by in categories: chemistry, particle physics, space travel

New solar observations indicate that plasma waves are responsible for the Sun’s outer atmosphere having different abundances of chemical elements than the Sun’s other layers.

The solar corona is a halo of hot, tenuous plasma that surrounds the Sun out to large distances. It is visible during solar eclipses (Fig. 1) but is usually outshone by the glare of the Sun’s surface, or photosphere. The corona has different abundances of chemical elements than the rest of the Sun, and a longstanding question has been why this disparity exists. New solar measurements by Mariarita Murabito at the Italian National Institute of Astrophysics (INAF) and colleagues suggest that the difference is caused by plasma waves dragging easily ionized elements from the Sun’s lower atmosphere into the corona [1]. This finding could lead to a better understanding of the structure of stars.

The corona is of great interest to solar physicists, partly because it produces the solar wind—an outflow of hot gas from the Sun. The solar wind is most evident to us on Earth when its particles become trapped in Earth’s magnetic field and collide with our atmosphere, causing an aurora. An important problem in solar physics is to determine which coronal structures generate the solar wind and how solar conditions affect the outflow’s properties. The elemental composition of the solar wind sheds light on its origins, as this composition does not change once the gas leaves the Sun. The solar wind can be directly sampled by spacecraft in situ, and its elemental abundances can be compared to coronal abundances inferred from spectroscopy.

May 24, 2024

Researchers develop organic photoredox catalysts with enhanced stability and recyclability

Posted by in categories: chemistry, energy

In recent years, global environmental concerns have prompted a shift toward eco-friendly manufacturing in the field of organic synthetic chemistry. In this regard, research into photoredox catalytic reactions, which use light to initiate redox or reduction-oxidation reactions via a photoredox catalyst, has gained significant attention. This approach reduces the reliance on harsh and toxic reagents and uses visible light, a clean energy source.

May 24, 2024

Combining human olfactory receptors with artificial organic synapses and a neural network to sniff out cancer

Posted by in categories: biotech/medical, chemistry, robotics/AI

A team of chemical and biological engineers at Seoul National University in the Republic of Korea has developed a proof-of-concept device that could one day lead to the creation of an artificial nose.

May 24, 2024

Researchers describe spin-boson systems to configure quantum devices

Posted by in categories: computing, particle physics, quantum physics

In a new publication in Physical Review Letters, researchers in Amsterdam demonstrate a way to describe spin-boson systems and use this to efficiently configure in a desired state.

Quantum devices use the quirky behavior of quantum particles to perform tasks that go beyond what “classical” machines can do, including quantum computing, simulation, sensing, communication and metrology. These devices can take many forms, such as a collection of superconducting circuits, or a lattice of atoms or ions held in place by lasers or electric fields.

Regardless of their physical realization, quantum devices are typically described in simplified terms as a collection of interacting two-level or spins. However, these spins also interact with other things in their surroundings, such as light in superconducting circuits or oscillations in the lattice of atoms or ions. Particles of light (photons) and vibrational modes of a lattice (phonons) are examples of bosons.

May 24, 2024

How a world record ‘squeeze’ could offer comfort for dark matter hunters

Posted by in categories: cosmology, particle physics, quantum physics

UNSW quantum engineers have developed a new amplifier that could help other scientists search for elusive dark matter particles.

May 24, 2024

Unlocking the secrets of supercritical fluids: Study offers insights into a hybrid state of matter

Posted by in category: futurism

A study now published in Nature Communications brings remarkable insights into the enigmatic behavior of supercritical fluids, a hybrid state of matter occupying a unique space between liquids and gases, and arising in domains that go from the pharmaceutical industry to planetary science. The obtained results are at the limit of current experimental possibilities and could only be obtained in a high flux neutron source such as the Institut Laue-Langevin (ILL).

May 24, 2024

New discoveries about the nature of light could improve methods for heating fusion plasma

Posted by in category: space

Both literally and figuratively, light pervades the world. It banishes darkness, conveys telecommunications signals between continents and makes visible the invisible, from faraway galaxies to the smallest bacterium. Light can also help heat the plasma within ring-shaped devices known as tokamaks as scientists worldwide strive to harness the fusion process to generate green electricity.

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