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Comment by Dr. Krishna Kumari Challa on April 12, 2024 at 9:49am

Plant more native trees to reduce landslide risk, control erosion, say researchers

Landslides typically occur under heavy rain. With the potential for increased precipitation due to climate change and a possible return to La Niña reinforcing slopes with native trees and shrubs could be an effective, economical and sustainable solution.

Homeowners, councils and state governments looking to build houses and infrastructure on or near slopes should reconsider cutting down trees or using artificial slope reinforcement to buttress vertical terrain against landslides and slips.

They should plant native trees and shrubs instead, according to scientists. Plants provide a sustainable, natural approach to slope reinforcement, compared to artificial methods, such as steel mesh or sprayed concrete. They also create and maintain crucial habitat.

Jiale Zhu et al, An experimental study on root-reinforced soil strength via a steel root analogue in unsaturated silty soil, Acta Geotechnica (2023). DOI: 10.1007/s11440-023-01918-0

Comment by Dr. Krishna Kumari Challa on April 12, 2024 at 9:25am

In a paper published in Cell in March 2024,  researchers show that the size ratio between UCYN-A (a short DNA sequence of what appeared to be from an unknown nitrogen-fixing cyanobacterium in Pacific Ocean seawater) and their algal hosts is similar across different species of the marine haptophyte algae Braarudosphaera bigelowii.

The researchers use a model to demonstrate that the growth of the host cell and UCYN-A are controlled by the exchange of nutrients. Their metabolisms are linked. This synchronization in growth rates led the researchers to call UCYN-A "organelle-like."

That's exactly what happens with organelles. If you look at the mitochondria and the chloroplast, it's the same thing: they scale with the cell.

But the scientists did not confidently call UCYN-A an organelle until confirming other lines of evidence. In the cover article of the journal Science, published recently, researchers show that UCYN-A imports proteins from its host cells.

That's one of the hallmarks of something moving from an endosymbiont to an organelle. They start throwing away pieces of DNA, and their genomes get smaller and smaller, and they start depending on the mother cell for those gene products—or the protein itself—to be transported into the cell.

These independent lines of evidence leave little doubt that UCYN-A has surpassed the role of a symbiont. And while mitochondria and chloroplasts evolved billions of years ago, the nitroplast appears to have evolved about 100 million years ago, providing scientists with a new, more recent perspective on organellogenesis.

The organelle also provides insight into ocean ecosystems. All organisms need nitrogen in a biologically usable form, and UCYN-A is globally important for its ability to fix nitrogen from the atmosphere. Researchers have found it everywhere from the tropics to the Arctic Ocean, and it fixes a significant amount of nitrogen.

 Tyler H. Coale et al, Nitrogen-fixing organelle in a marine alga, Science (2024). DOI: 10.1126/science.adk1075

Francisco M. Cornejo-Castillo et al, Metabolic trade-offs constrain the cell size ratio in a nitrogen-fixing symbiosis, Cell (2024). DOI: 10.1016/j.cell.2024.02.016

Part 2

Comment by Dr. Krishna Kumari Challa on April 12, 2024 at 9:20am

Scientists discover first nitrogen-fixing organelle

Biology textbooks have to be re-written now. Because  they assert that only bacteria can take nitrogen from the atmosphere and convert it into a form that is usable for life. Plants that fix nitrogen, such as legumes, do so by harbouring symbiotic bacteria in root nodules. But a recent discovery upends that rule.

In two recent papers, an international team of scientists describes the first known nitrogen-fixing organelle within a eukaryotic cell. The organelle is the fourth example in history of primary endosymbiosis—the process by which a prokaryotic cell is engulfed by a eukaryotic cell and evolves beyond symbiosis into an organelle.

It's very rare that organelles arise from these types of things. 

The first time we think it happened, it gave rise to all complex life. Everything more complicated than a bacterial cell owes its existence to that event leading  to the origins of the mitochondria. A billion years ago or so, it happened again with the chloroplast, and that gave us plants.

The third known instance involves a microbe similar to a chloroplast.

The newest discovery is the first example of a nitrogen-fixing organelle, which the researchers are calling a "nitroplast".
Part 1

Comment by Dr. Krishna Kumari Challa on April 11, 2024 at 9:48am

Witness the awe-inspiring spectacle of explosive solar phenomena during the April 8 total eclipse! Expert analysis delves into solar flares, coronal mass ejections, and mesmerizing sunspots

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

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