Comment

Comment by Dr. Krishna Kumari Challa on April 11, 2024 at 9:15am

AI makes retinal imaging 100 times faster, compared to manual method

Researchers  have applied artificial intelligence (AI) to a technique that produces high-resolution images of cells in the eye. They report that with AI, imaging is 100 times faster and improves image contrast 3.5-fold. The advance, they say, will provide researchers with a better tool to evaluate age-related macular degeneration (AMD) and other retinal diseases.

 Vineeta Das, Furu Zhang, Andrew Bower, et al. Revealing speckle obscured living human retinal cells with artificial intelligence assisted adaptive optics optical coherence tomography, Communications Medicine (2024). DOI: 10.1038/s43856-024-00483-1

Comment by Dr. Krishna Kumari Challa on April 11, 2024 at 9:12am

Physicists discover a novel quantum state in an elemental solid

Physicists have observed a novel quantum effect termed "hybrid topology" in a crystalline material. This finding opens up a new range of possibilities for the development of efficient materials and technologies for next-generation quantum science and engineering.

The finding, published in Nature, came when  scientists discovered that an elemental solid crystal made of arsenic (As) atoms hosts a never-before-observed form of topological quantum behaviour. They were able to explore and image this novel quantum state using a scanning tunneling microscope (STM) and photoemission spectroscopy, the latter a technique used to determine the relative energy of electrons in molecules and atoms.

This state combines, or "hybridizes," two forms of topological quantum behavior—edge states and surface states, which are two types of quantum two-dimensional electron systems. These have been observed in previous experiments, but never simultaneously in the same material where they mix to form a new state of matter.

M. Zahid Hasan, A hybrid topological quantum state in an elemental solid, Nature (2024). DOI: 10.1038/s41586-024-07203-8. www.nature.com/articles/s41586-024-07203-8

Comment by Dr. Krishna Kumari Challa on April 11, 2024 at 8:28am

Unlike amplifiers, bolometers very subtly sense microwave photons emitted from the qubit via a minimally invasive detection interface. This form factor is roughly 100 times smaller than its amplifier counterpart, making it extremely attractive as a measurement device.
In their very first experiments, they found these bolometers accurate enough for single-shot readout, free of added quantum noise, and they consume 10,000 times less power than the typical amplifiers—all in a tiny bolometer, the temperature-sensitive part of which can fit inside of a single bacterium.
Single-shot fidelity is an important metric physicists use to determine how accurately a device can detect a qubit's state in just one measurement as opposed to an average of multiple measurements. In the case of the QCD group's experiments, they were able to obtain a single-shot fidelity of 61.8% with a readout duration of roughly 14 microseconds. When correcting for the qubit's energy relaxation time, the fidelity jumps up to 92.7%.

With minor modifications, they could expect to see bolometers approaching the desired 99.9% single-shot fidelity in 200 nanoseconds. For example, they can swap the bolometer material from metal to graphene, which has a lower heat capacity and can detect very small changes in its energy quickly. And by removing other unnecessary components between the bolometer and the chip itself, they can not only make even greater improvements on the readout fidelity, but they can achieve a smaller and simpler measurement device that makes scaling-up to higher qubit counts more feasible.

András M. Gunyhó, Single-Shot Readout of a Superconducting Qubit Using a Thermal Detector, Nature Electronics (2024). DOI: 10.1038/s41928-024-01147-7

Comment by Dr. Krishna Kumari Challa on April 11, 2024 at 8:24am

First ever measurement of qubits with ultrasensitive thermal detectors, evading Heisenberg uncertainty principle

Chasing ever-higher qubit counts in near-term quantum computers constantly demands new feats of engineering.

Among the troublesome hurdles of this scaling-up race is refining how qubits are measured. Devices called parametric amplifiers are traditionally used to do these measurements. But as the name suggests, the device amplifies weak signals picked up from the qubits to conduct the readout, which causes unwanted noise and can lead to decoherence of the qubits if not protected by additional large components. More importantly, the bulky size of the amplification chain becomes technically challenging to work around as qubit counts increase in size-limited refrigerators. Researchers have now demonstrated in a Nature Electronics paper that bolometer measurements can be accurate enough for single-shot qubit readout.
To the chagrin of many physicists, the Heisenberg uncertainty principle determines that one cannot simultaneously know a signal's position and momentum, or voltage and current, with accuracy. So it goes with qubit measurements conducted with parametric voltage-current amplifiers.

But bolometric energy sensing is a fundamentally different kind of measurement—serving as a means of evading Heisenberg's infamous rule. Since a bolometer measures power, or photon number, it is not bound to add quantum noise stemming from the Heisenberg uncertainty principle in the way that parametric amplifiers are.
Part1

Comment by Dr. Krishna Kumari Challa on April 10, 2024 at 9:36am

Write it down, then throw it away: Research confirms a simple method for reducing anger

A research group  has discovered that writing down one's reaction to a negative incident on a piece of paper and then shredding it or throwing it away reduces feelings of anger.

This research is important because controlling anger at home and in the workplace can reduce negative consequences in our jobs and personal lives. Unfortunately, many anger management techniques proposed by specialists lack empirical research support. They can also be difficult to recall when angry.

The results of this study, published in Scientific Reports, are the culmination of years of previous research on the association between the written word and anger reduction. It builds on work showing how interactions with physical objects can control a person's mood.

Yuta Kanaya et al, Anger is eliminated with the disposal of a paper written because of provocation, Scientific Reports (2024). DOI: 10.1038/s41598-024-57916-z , doi.org/10.1038/s41598-024-57916-z

Comment by Dr. Krishna Kumari Challa on April 9, 2024 at 8:51am

While it is possible to painstakingly reassemble and restore such tapes, these researchers are pursuing a completely new approach. They use synchrotron radiation : With X-ray light from a synchrotron, they can reconstruct even heavily damaged tape fragments without even touching them.

Audio tapes store information in a layer of tiny magnetic particles—like little compass needles pointing either north or south. When the tape is recorded, their magnetic orientation is changed—the tape becomes magnetized, and the audio information is now physically stored in the orientation pattern. To play back this pattern, the tape is moved past a play head. As the magnetic field constantly changes through the pattern, a voltage is induced in the play head and an electrical signal is generated. This signal is amplified and converted into an acoustic signal.

With his new X-ray method, researchers do not rely on the magnetic field, but on the individual compass needles that generate this field. The magnetization states of these tiny particles, whose size is smaller than a tenth of the diameter of a human hair, can be read out almost individually using the X-ray light of the SLS and converted into a high-quality audio signal.

Since the synchrotron light can measure almost every single magnetic compass needle on the tape, it can achieve unprecedented resolution.

https://www.psi.ch/en/media/our-research/rescuing-music-with-x-rays

Part 2

Comment by Dr. Krishna Kumari Challa on April 9, 2024 at 8:47am

A physicist uses X-rays to rescue old music recordings

Researchers are developing a technique that uses the special synchrotron X-ray light from the Swiss Light Source SLS to non-destructively digitize recordings from high-value historic audio tapes—including treasures from the Montreux Jazz Festival archive, such as a rare recording of the King of the Blues, B.B. King.

Magnetic tapes have almost completely disappeared from our lives and now only enjoy a nostalgic niche existence. However, significant quantities of these analog magnetic media are still stored in the archives of sound studios, radio and TV stations, museums, and private collections worldwide. Digitizing these tapes is an ongoing challenge as well as a race against time, as the tapes degrade and eventually become unplayable. Physicists and experts in nanomagnetism, are developing a method to non-destructively digitize degraded audio tapes in the highest quality using X-ray light. To achieve this goal, they have been collaborating with the Swiss National Sound Archives, which has produced custom-made reference recordings and provided audio engineering know-how. Now, a partnership with the Montreux Jazz Digital Project will help to further develop and test the method.
The remaining members of the famous rock band Queen recently faced a big challenge. In their studio, the musicians found a tape from 1988 containing a song with the voice of their legendary singer Freddie Mercury, who died in 1991. However, the tape was badly damaged. At first, no one believed they would be able to save this special piece. With great effort, the sound engineers managed to succeed after all.
Part 1

Comment by Dr. Krishna Kumari Challa on April 9, 2024 at 8:22am

The classic version of the game of 'chicken' pits two drivers against each other on a collision course.

To carry out their experiments, Israel, Cherki and their colleagues used a laboratory-based adaptation of the chicken game, known as the "intergroup chicken game." This version of the game has the same underlying rules, but with players divided into groups that are pitted against each other.

The researchers' experiment was double-blind and included a placebo condition. They recruited 204 participants and divided them into groups of eight or 12, each of which contained an equal number of males and females.

These groups of participants completed 30 rounds of the intergroup chicken game and at the beginning of each experimental session, participants were asked to self-administer either a placebo gas or oxytocin. Notably, neither the participants nor the experimenters were aware of what was being inhaled, which eliminated biases and prevented prior knowledge of what was administered during each trial from impacting the results.

One of the most notable observations of this study was that the interaction between oxytocin and testosterone greatly influenced the behavior of male participants. Contrarily, the interplay between these two hormones did not appear to impact the behavior of female participants.

Researchers observed that under placebo conditions, elevations in testosterone levels corresponded to heightened aggression towards outgroups. However, the administration of internasal oxytocin cancelled out this association, suggesting a regulatory role for oxytocin in moderating testosterone-induced aggression within intergroup dynamics.

Overall, the recent findings gathered by this team of researchers suggest that there could be notable sex differences in the dynamics underlying parochial altruism in intergroup conflict. In fact, they showed no substantial link between testosterone reactivity and outgroup aggression in females.

This underscores the importance of considering sex-specific effects when examining the neurobiological underpinnings of social behaviour.

 Boaz R. Cherki et al, Intranasal oxytocin interacts with testosterone reactivity to modulate parochial altruism, Communications Psychology (2024). DOI: 10.1038/s44271-024-00066-9

Part 3

**

Comment by Dr. Krishna Kumari Challa on April 9, 2024 at 8:18am

Previous research,  suggested independent roles of oxytocin and testosterone—hormones that are associated with intergroup relations and cooperation-aggression—in shaping behaviour during intergroup conflict.

How the two hormones interact, had yet to be tested. These hormones exert contrasting effects on various social behaviors, leading us to hypothesize that their combined influence might hold the key to understanding intergroup dynamics. This study filled that gap.

The primary objective of the recent work  by researchers was to better understand how the interaction between oxytocin and testosterone influences behavior in the context of intergroup conflict. While many past studies focusing on this topic only included male participants, the researchers decided to also include female participants, as this would allow them to discover any sex differences that may exist.
To model intergroup conflict in an experimental setting, the researchers used an adaptation of the game commonly referred to as "chicken." This game has often been portrayed in popular media, including in the movies "Rebel without a Cause," "Footloose" and "Grease," and is also used in political science to describe elements of conflict between nations, such as the nuclear brinkmanship of the Cuban Missile crisis.
Part 2

Comment by Dr. Krishna Kumari Challa on April 9, 2024 at 8:16am

Exploring how oxytocin interacts with testosterone while humans play a game modeling intergroup conflict

Over the past decades, numerous studies have investigated the neural and cognitive processes underpinning intergroup conflict, as this could help to explain what fuels belligerent behavior, political clashes, and wars. While these works gathered some interesting findings, much about these processes remains poorly understood until now.

Researchers  recently carried out a study specifically exploring how the hormones oxytocin and testosterone modulate people's behavior during an experimental game modeling intergroup conflict.

Their findings, published in Communications Psychology, suggest that oxytocin interacts with men's testosterone reactivity to modulate parochial altruism (i.e., behavior that benefits the group one belongs to, while negatively impacting competing groups).

Individuals regularly carry out actions which are costly to themselves, but advance the interests of their own group, often even at the expense of rival groups.

We see examples of such behavior all the time, including sports rivalries (playing injured), political partisanship (voting along party lines), and in extreme cases ethnic, religious, or national conflicts.

"Evolutionary theories, going back to Darwin, suggest that such acts of parochial altruism—the favoring of one's ingroup—emerged during human ancestry because they provided an advantage for group survival."

The researchers set out to study how individuals make decisions in a controlled laboratory setting modeling intergroup conflict, as this could shed light on the dynamics driving behaviors commonly observed outside laboratory settings.

Past social psychology research consistently found that people's social regard (i.e., their willingness to trust others, empathize with them and behave altruistically) is greatly influenced by their belonging to specific groups. Nonetheless, the biological underpinnings of these group-driven behaviors are yet to be clearly elucidated.

Part 1

• ‹ Previous
• 1
• …
• 208
• 209
• 210
• 211
• 212
• …
• 1043
• Next ›
• Page