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Comment by Dr. Krishna Kumari Challa on August 22, 2024 at 8:56am

Researchers train a robot dog to combat invasive fire ants

A multidisciplinary research team based across China and Brazil has used a dog-like robot and AI to create a new way to find fire ant nests. Published in the journal Pest Management Science, the study highlights how a "CyberDog" robot integrated with an AI model can automate the identification and control of Red Imported Fire Ants (RIFA), a globally destructive pest.

Field tests carried out by the researchers reveal the robotic system can significantly outperform human inspectors, identifying three times more RIFA nests with greater precision.

Fire ant nests are difficult for untrained personnel to identify and confirm in the field, and searching large areas can be time-consuming and exhausting under the hot sun. A robot could automatically locate the nests without requiring specially trained individuals and operate at various times of the day regardless of temperature conditions.

They conducted rigorous field tests to measure the system's effectiveness. The CyberDog was programmed to press the nest with its front paw: when a fire ant nest mound is disturbed, the workers will rush out from cracks and openings displaying aggressive behavior. This, the researchers said, is key for diagnosing active mounds from abandoned nests, and to avoid false positives with mounds inhabited by other species.

The implementation of robotic dogs in automatic detection and surveillance of red imported fire ant nests, Pest Management Science (2024). DOI: 10.1002/ps.8254

Comment by Dr. Krishna Kumari Challa on August 22, 2024 at 8:51am

This simple schematic shows how the Wow! Signal was generated and detected. A radiative source such as a magnetar or a soft gamma repeater is positioned behind a cloud of cold neutral hydrogen. Energy from the source stimulates emission from the HI cloud, which brightens abruptly and is observable from Earth. Credit: arXiv (2024). DOI: 10.48550/arxiv.2408.08513

Part 3

Comment by Dr. Krishna Kumari Challa on August 22, 2024 at 8:48am

The researchers hypothesize that the Wow! Signal was caused by sudden brightening from stimulated emission of the hydrogen line due to a strong transient radiation source, such as a magnetar flare or a soft gamma repeater (SGR)," they write. Those events are rare and rely on precise conditions and alignments. They can cause clouds of hydrogen to brighten considerably for seconds or even minutes.

The researchers say that what Big Ear saw in 1977 was the transient brightening of one of several H1 (neutral hydrogen) clouds in the telescope's line of sight. The 1977 signal was similar to what the researchers saw now in many respects. The only difference between the signals observed now and the Wow! Signal is their brightness. It is precisely the similarity between these spectra that suggests a mechanism for the origin of the mysterious signal," the authors write.
These signals are rare because the spatial alignment between source, cloud, and observer is rare. The rarity of alignment explains why detections are so rare.
The new hypothesis explains all observed properties of the Wow! Signal, proposes a new source of false positives in technosignature searches, and suggests that the Wow! Signal could be the first recorded event of an astronomical maser flare in the hydrogen line," the authors explain in their conclusion.

 Abel Méndez et al, Arecibo Wow! I: An Astrophysical Explanation for the Wow! Signal, arXiv (2024). DOI: 10.48550/arxiv.2408.08513

Comment by Dr. Krishna Kumari Challa on August 22, 2024 at 8:46am

The Wow! Signal deciphered—it was hydrogen all along, study says

In 1977, astronomers received a powerful, peculiar radio signal from the direction of the constellation Sagittarius. Its frequency was the same as neutral hydrogen, and astronomers had speculated that any ETIs attempting to communicate would naturally use this frequency. Now the signal, named the WOW! Signal has become lore in the SETI world.

The signal has another name: 6EQUJ5. This has been interpreted as a message hidden in the signal, but it really represents how the signal's intensity varied over time.

The signal generated a lot of excitement. Some thought it was extraterrestrial in origin, some thought it could come from some type of human-generated interference, and some thought it could be from an unexplained natural phenomenon.

New research shows that the Wow! Signal has an entirely natural explanation.

The research is titled "Arecibo Wow! I: An Astrophysical Explanation for the Wow! Signal." The lead author is Abel Méndez from the Planetary Habitability Laboratory at the University of Puerto Rico at Arecibo. It's available on the preprint server arXiv.

The latest observations, made between February and May 2020, have revealed similar narrowband signals near the hydrogen line, though less intense than the original Wow! Signal

Researchers detected signals similar to the Wow! signal but with some differences. They're far less intense and come from multiple locations. The authors say these signals are easily explained by an astrophysical phenomenon and that the original Wow! signal is too.

Part 1

Comment by Dr. Krishna Kumari Challa on August 22, 2024 at 8:38am

Crystal coating keeps clothes feeling cool

Wouldn’t it be nice if your clothes could keep you as cool as your A/C? This new, durable fabric coating can cool the wearer by up to 15 degrees Fahrenheit without using any additional energy, thanks to special crystals that reflect both infrared and ultraviolet light.

“Functional reflective textile coatings for personal cooling” Presented at ACS Fall 2024 on Aug. 21, 2024

Comment by Dr. Krishna Kumari Challa on August 22, 2024 at 8:31am

A free-living eukaryote is the first known to have lost its mitochondria

An international team of geneticists and molecular biologists has discovered the first-known, free-living eukaryote to have lost its mitochondria. In their study, published in Nature Communications, the group found the eukaryote while investigating the patterns and processes of genome and mitochondrion-related organelles' evolution in metamonads in water samples collected from saltwater lakes and shallow marine environments.

Mitochondria are organelles in almost every living eukaryotic cell on Earth. They are responsible for generating the energy that allows creatures to grow and to move around. Mitochondria have a double membrane and use aerobic respiration to generate adenosine triphosphate (ATP)—the fuel that provides the energy for the cell. Eukaryotes belong to one of four types: plants, animals, fungi and protists.

Prior research has shown that there are eukaryotes that have devolved mitochondria to the point that they have none—generally because they get their energy elsewhere. Such creatures are able to gather energy by absorbing nutrients directly from another creature that does have functioning mitochondria—several have been found in the human gut, for example.

For this new research, the team studied eukaryote evolution in metamonads, a type of microscopic eukaryote. They collected specimens from various locations and studied them in their lab. They found five that caught their eye: three found in salty soda lake sediment beds and two in shallow ocean sediments.

One stood out clearly from the other four due to its complete lack of mitochondria. They named it Skoliomonas litria and noted that it was the first-ever finding of a free-living eukaryote to have lost its mitochondria. They also note that more work is required to determine how the creature makes its ATP without using oxygen.

Shelby K. Williams et al, Extreme mitochondrial reduction in a novel group of free-living metamonads, Nature Communications (2024). DOI: 10.1038/s41467-024-50991-w

Comment by Dr. Krishna Kumari Challa on August 22, 2024 at 8:27am

If you have protocell populations that are unstable, they will exchange their genetic material with each other and become clones. There is no possibility of Darwinian evolution. But if they stabilize against exchange so that they store their genetic information well enough, at least for several days, so that the mutations can happen in their genetic sequences, then a population can evolve.
In their experiments with the actual rainwater and with lab water modified to mimic the acidity of rainwater, the researchers found the same results. The meshy walls formed, creating the conditions that could have led to life.
The new paper proves that this approach of building a meshy wall around protocells is possible and can work together to compartmentalize the molecules of life, putting researchers closer than ever to finding the right set of chemical and environmental conditions that allow protocells to evolve.

Aman Agrawal et al, Did the exposure of coacervate droplets to rain make them the first stable protocells?, Science Advances (2024). DOI: 10.1126/sciadv.adn9657. www.science.org/doi/10.1126/sciadv.adn9657

Part 2

Comment by Dr. Krishna Kumari Challa on August 22, 2024 at 8:24am

New research suggests rainwater helped form the first protocell walls

In the paper, published in Science Advances researchers show how rainwater could have helped create a meshy wall around protocells 3.8 billion years ago, a critical step in the transition from tiny beads of RNA to every bacterium, plant, animal, and human that ever lived.

The research looks at "coacervate droplets"—naturally occurring compartments of complex molecules like proteins, lipids, and RNA. The droplets, which behave like drops of cooking oil in water, have long been eyed as a candidate for the first protocells. But there was a problem. It wasn't that these droplets couldn't exchange molecules between each other, a key step in evolution, the problem was that they did it too well, and too fast.

Any droplet containing a new, potentially useful pre-life mutation of RNA would exchange this RNA with the other RNA droplets within minutes, meaning they would quickly all be the same. There would be no differentiation and no competition—meaning no evolution.

And that means no life. If molecules continually exchange between droplets or between cells, then all the cells after a short while will look alike, and there will be no evolution because you are ending up with identical clones.

DNA is the molecule which encodes information, but it cannot do any function. Proteins are the molecules which perform functions, but they don't encode any heritable information.

RNA is a molecule which, like DNA, can encode information, but it also folds like proteins so that it can perform functions such as catalysis as well.

RNA was a likely candidate for the first biological material. Coacervate droplets were likely candidates for the first protocells. Coacervate droplets containing early forms of RNA seemed a natural next step.

What the researchers now showed in this new paper is that you can overcome at least part of that problem by transferring these coacervate droplets into distilled water—for example, rainwater or freshwater of any type—and they get a sort of tough skin around the droplets that restricts them from exchanging RNA content.

Where do you think distilled water could come from in a prebiotic world? Rain!

Working with RNA samples the researchers found that transferring coacervate droplets into distilled water increased the time scale of RNA exchange—from mere minutes to several days. This was long enough for mutation, competition, and evolution.

Part 1

Comment by Dr. Krishna Kumari Challa on August 22, 2024 at 8:14am

The researchers who developed this microscope based their work on the Nobel Prize-winning accomplishments of Pierre Agostini, Ferenc Krausz and Anne L'Huilliere, who won the Novel Prize in Physics in 2023 after generating the first extreme ultraviolet radiation pulse so short it could be measured in attoseconds.

Using that work as a steppingstone, the researchers developed a microscope in which a powerful laser is split and converted into two parts—a very fast electron pulse and two ultra-short light pulses. The first light pulse, known as the pump pulse, feeds energy into a sample and causes electrons to move or undergo other rapid changes.

The second light pulse, also called the "optical gating pulse" acts like a gate by creating a brief window of time in which the gated, single attosecond electron pulse is generated. The speed of the gating pulse therefore dictates the resolution of the image. By carefully synchronizing the two pulses, researchers control when the electron pulses probe the sample to observe ultrafast processes at the atomic level.
The electron movements happen in attoseconds. But now, for the first time, researchers are able to attain attosecond temporal resolution with their electron transmission microscope—and they coined it 'attomicroscopy.' For the first time, they could see pieces of the electron in motion.

Dandan Hui et al, Attosecond electron microscopy and diffraction, Science Advances (2024). DOI: 10.1126/sciadv.adp5805. www.science.org/doi/10.1126/sciadv.adp5805

Part 2

Comment by Dr. Krishna Kumari Challa on August 22, 2024 at 8:11am

Researchers develop world's fastest microscope that can see electrons in motion

Imagine owning a camera so powerful it can take freeze-frame photographs of a moving electron—an object traveling so fast it could circle the Earth many times in a matter of a second. Researchers have developed the world's fastest electron microscope that can do just that.

And they think their work will lead to groundbreaking advancements in physics, chemistry, bioengineering, materials sciences and more.

This transmission electron microscope is like a very powerful camera in the latest version of smart phones; it allows us to take pictures of things we were not able to see before—like electrons. With this microscope, the researchers hope the scientific community can understand the quantum physics behind how an electron behaves and how an electron moves.

A transmission electron microscope is a tool used by scientists and researchers to magnify objects up to millions of times their actual size in order to see details too small for a traditional light microscope to detect.

Instead of using visible light, a transmission electron microscope directs beams of electrons through whatever sample is being studied. The interaction between the electrons and the sample is captured by lenses and detected by a camera sensor in order to generate detailed images of the sample.

Ultrafast electron microscopes using these principles were first developed in the 2000's and use a laser to generate pulsed beams of electrons. This technique greatly increases a microscope's temporal resolution—its ability to measure and observe changes in a sample over time.

In these ultrafast microscopes, instead of relying on the speed of a camera's shutter to dictate image quality, the resolution of a transmission electron microscope is determined by the duration of electron pulses.

The faster the pulse, the better the image.

Ultrafast electron microscopes previously operated by emitting a train of electron pulses at speeds of a few attoseconds. An attosecond is one quintillionth of a second. Pulses at these speeds create a series of images, like frames in a movie—but scientists were still missing the reactions and changes in an electron that takes place in between those frames as it evolves in real time.

In order to see an electron frozen in place,  researchers, for the first time, generated a single attosecond electron pulse, which is as fast as electrons move, thereby enhancing the microscope's temporal resolution, like a high-speed camera capturing movements that would otherwise be invisible.

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