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Comment by Dr. Krishna Kumari Challa on December 22, 2022 at 12:11pm

The physical intelligence of ant and robot collectives

Researchers took inspiration from ants to design a team of relatively simple robots that can work collectively to perform complex tasks using only a few basic parameters.

https://techxplore.com/news/2022-12-physical-intelligence-ants-robo...

Comment by Dr. Krishna Kumari Challa on December 22, 2022 at 11:35am

Study finds birds build hanging-nests to protect offspring from nest invaders

A new study has found that birds build hanging-nests, particularly those with extended entrance tunnels, to help protect offspring against nest invaders like snakes and parasitic cuckoos.

Researchers examined the relationship between nest design and the length of time offspring spend in the nest before fledging across species of weaverbirds and icterids, two bird families renowned for their complex woven nests. They found that species building the most elaborate nests, particularly those with long entrance tunnels, produce offspring with longer developmental periods.

Nests with longer entrance tunnels are more effective at hindering access by nest invaders than shorter tunnels and thereby limits the exposure of developing offspring to nest invaders.

Researchers suggest that the complex structural features in these nests do indeed play a role in protecting offspring from predators and brood parasites. They find the consistency of these findings "striking" given that highly elaborate nests have evolved independently in the weaverbirds and icterids.

Sally Street et al, Convergent evolution of elaborate nests as structural defences in birds, Proceedings of the Royal Society B: Biological Sciences (2022). DOI: 10.1098/rspb.2022.1734. royalsocietypublishing.org/doi … .1098/rspb.2022.1734

Comment by Dr. Krishna Kumari Challa on December 21, 2022 at 12:41pm

New software based on artificial intelligence helps to interpret co...

More is not always better—sometimes, it's a problem. With highly complex data, which have many dimensions due to their numerous parameters, correlations are often no longer recognizable. Especially since experimentally obtained data are additionally disturbed and noisy due to influences that cannot be controlled.

Comment by Dr. Krishna Kumari Challa on December 21, 2022 at 12:25pm

Human-caused emissions create new cloud-forming particles

Human activity is changing atmospheric chemistry—even in remote places—that could alter how and when clouds form.

That's the conclusion of a new study by scientists, which finds that at a laboratory on a mountaintop in Colorado, new aerosol particles are forming in the air on average every other day and that those particles, likely formed from gases emitted by nearby power plants, can grow until they're big enough for water to condense around, forming clouds.

The study draws an important scientific link, using newly developed statistical methods, that link aerosol growth to measured cloud condensation nuclei—which are the critical ingredients for accurately modeling the role of aerosols and clouds in climate change. 

 To form, clouds need something in the air, such as a speck of dirt or salt, around which to begin condensing water vapor. These somethings, about a tenth of the diameter of spider silk, are particles called "cloud condensation nuclei."

It's known that increased aerosols in the atmosphere lead to more cloud formation, and more reflective clouds. But it's not known whether new aerosol particles, much smaller than cloud condensation nuclei and formed with human-caused emissions, can grow into cloud condensation nuclei. And it's also not known how to incorporate the relationship between aerosols and clouds in climate models. As you might imagine, clouds play a large role in the climate, reflecting solar energy and moving water from one place to another. So being able to realistically model those clouds could help increase the accuracy of the models forecasting changes in our climate.

Noah S. Hirshorn et al, Seasonal significance of new particle formation impacts on cloud condensation nuclei at a mountaintop location, Atmospheric Chemistry and Physics (2022). DOI: 10.5194/acp-22-15909-2022

Comment by Dr. Krishna Kumari Challa on December 21, 2022 at 12:00pm

Three quarters of major observatories affected by light pollution

Researchers  have studied and compared the light pollution levels at major astronomical observatories across the world. The study shows that light is polluting the sky above most observatories and that immediate action is needed to decrease the amount of contamination coming from artificial light. The work was published in Monthly Notices of the Royal Astronomical Society.

The study presents the light pollution levels above almost 50 observatories across the globe, including the world's largest professional observatories, as well as smaller observatories for amateurs. The study utilizes a model of propagation of light in the Earth's atmosphere and applies it to night-time satellite data. Using additional light pollution indicators, beyond examining the traditional brightness directly overhead (i.e. at the zenith), reveals that the night sky at major observatory sites is more polluted than one may assume. The zenith is generally the less polluted, therefore darker, zone of the night sky, and is one of the indicators used to classify the sites in the study. The additional indicators are the average brightness at a 30° altitude above the horizon, the average brightness in the first 10° above the horizon, the overall average brightness across the sky, and the illuminance of the ground given by the artificial light coming from the night sky. These indicators, along with the overhead brightness, help to decipher how artificial light affects the night sky.

The key measure is the comparison with the natural sky brightness caused by airglow in the high atmosphere, and light originating from stars and the Milky Way. The study results show that only 7 of the 28 major astronomical observatory sites (sites that host a telescope with a diameter of 3 meters or more) have a zenith sky brightness with light pollution below the expected threshold of 1% of natural sky brightness, and so could be considered almost uncontaminated in that direction. This leaves the remaining 21 other major sites—three quarters of all the major observatories—all above this level. The lowest pointing direction of ground-based telescopes is around 30° above the horizon. Only one observatory of the 28 major sites has light pollution in that direction below the 1% level. A more relaxed 10% limit was set by the International Astronomical Union in the 1970s as the maximum allowable artificial brightness for major observatories. The new study shows that light pollution at two thirds of the ground based observatories in the study has now crossed this higher threshold.

Fabio Falchi et al, Light pollution indicators for all the major astronomical observatories, Monthly Notices of the Royal Astronomical Society (2022). DOI: 10.1093/mnras/stac2929

Comment by Dr. Krishna Kumari Challa on December 21, 2022 at 11:49am

One of the really interesting properties of the human brain is how it embodies a rich constellation of networks that are active even when we are at rest. These networks create the biological infrastructure of the mind and are thought to be intrinsic properties of the brain.

These include the frontoparietal network, which enables cognitive control and goal-directed decision-making; the dorsal attention network, which aids in visual and spatial awareness; and the salience network, which directs attention to the most relevant stimuli. Previous studies have shown that the activity of these and other networks when a person is awake but not engaged in a task or paying attention to external events "reliably predicts our cognitive skills and abilities".

With the cognitive tests and fMRI data, the researchers were able to evaluate which theories best predicted how participants performed on the intelligence tests.

We can systematically investigate how well a theory predicts general intelligence based on the connectivity of brain regions or networks that theory entails. This approach allowed the researchers to directly compare evidence for the neuroscience predictions made by current theories.

The researchers found that taking into account the features of the whole brain produced the most accurate predictions of a person's problem-solving aptitude and adaptability. This held true even when accounting for the number of brain regions included in the analysis.

The other theories also were predictive of intelligence, the researchers said, but the network neuroscience theory  outperformed those limited to localized brain regions or networks in a number of respects.

The findings reveal that "global information processing" in the brain is fundamental to how well an individual overcomes cognitive challenges.

Rather than originate from a specific region or network, intelligence appears to emerge from the global architecture of the brain and to reflect the efficiency and flexibility of systemwide network function. 

Investigating cognitive neuroscience theories of human intelligence: A connectome-based predictive modeling approach, Human Brain Mapping (2022). DOI: 10.1002/hbm.26164

Part 2

Comment by Dr. Krishna Kumari Challa on December 21, 2022 at 11:45am

Network neuroscience theory best predictor of intelligence, study finds

Scientists have laboured for decades to understand how brain structure and functional connectivity drive intelligence. A new analysis offers the clearest picture yet of how various brain regions and neural networks contribute to a person's problem-solving ability in a variety of contexts, a trait known as general intelligence, researchers report.

The study used "connectome-based predictive modeling" to compare five theories about how the brain gives rise to intelligence. 

To understand the remarkable cognitive abilities that underlie intelligence, neuroscientists look to their biological foundations in the brain. Modern theories attempt to explain how our capacity for problem-solving is enabled by the brain's information-processing architecture. A biological understanding of these cognitive abilities requires 'characterizing how individual differences in intelligence and problem-solving ability relate to the underlying architecture and neural mechanisms of brain networks'. Historically, theories of intelligence focused on localized brain regions such as the prefrontal cortex, which plays a key role in cognitive processes such as planning, problem-solving and decision-making. More recent theories emphasize specific brain networks, while others examine how different networks overlap and interact with one another.

Strong connections involve highly connected hubs of information-processing that are established when we learn about the world and become adept at solving familiar problems. Weak connections have fewer neural linkages but enable flexibility and adaptive problem-solving. Together, these connections provide the network architecture that is necessary for solving the diverse problems we encounter in life.

Part 1

Comment by Dr. Krishna Kumari Challa on December 21, 2022 at 11:40am

Developing antibiotics that target multiple-drug-resistant bacteria

Researchers have designed and synthesized analogs of a new antibiotic that is effective against multidrug-resistant bacteria, opening a new front in the fight against these infections.

Antibiotics are vital drugs in the treatment of a number of bacterial diseases. However, due to continuing overuse and misuse, the number of bacteria strains that are resistant to multiple antibiotics is increasing, affecting millions of people worldwide. The development of new antibacterial compounds that target multiple drug resistant bacteria is also an active field of research so that this growing issue can be controlled.

Scientists have been working on the development of new antibacterials. Their most recent research, published in the journal Nature Communications, details the development of a highly effective antibacterial compound that is effective against the most common multidrug-resistant bacteria.

 worked on a class of antibacterial compounds called sphaerimicins. These compounds block the function of a protein in the bacteria called MraY. MraY is essential for the replication of bacteria and plays a role in the synthesis of the bacterial cell wall; it is also not a target of currently available commercial antibiotics.

The team analyzed structures of sphaerimicin A by molecular modeling assisted by calculation, and designed and synthesized two analogs of sphaerimicin, SPM1 and SPM2. These analogs were found to be effective against Gram positive bacteria.

They then determined the structure of SPM1 bound to MraY. By studying this structure and comparing it to that of related antibacterial agents, they determined how to further simplify the molecules. They were successful in developing a simpler analog, SPM3, whose activity was similar to SPM1.

In addition to their effectiveness against MRSA and VRE, the SPMs were also effective against Mycobacterium tuberculosis, the bacteria that causes tuberculosis—and which has multidrug-resistant strains.

Satoshi Ichikawa et al, Synthesis of macrocyclic nucleoside antibacterials and their interactions with MraY, Nature Communications (2022). DOI: 10.1038/s41467-022-35227-z

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Comment by Dr. Krishna Kumari Challa on December 20, 2022 at 8:17am

Study uncovers existing limitations in the detection of entanglement

Quantum entanglement is a process through which two particles become entangled and remain connected over time, even when separated by large distances. Detecting this phenomenon is of crucial importance for both the development of quantum technology and the study of quantum many-body physics.

Researchers  have recently carried out a study exploring the possible reasons why the reliable and efficient detection of entanglement in complex and "noisy" systems has often proved to be very challenging. Their findings, published in Physical Review Letters, hint at the existence of a trade-off between the effectiveness and efficiency of entanglement detection methods.

This new work showed that to observe entanglement on a large-scale, researchers must be able to control all interactions in a system with high precision and know almost all information about them. When there is a lot of uncertainty about the system, therefore, the probability of detecting its entanglement is very small, even if one is almost certain of its occurrence.

This proved that no entanglement detection protocols are both efficient and effective. This may help the design of entanglement detection protocols in the future.

Pengyu Liu et al, Fundamental Limitation on the Detectability of Entanglement, Physical Review Letters (2022). DOI: 10.1103/PhysRevLett.129.230503

Karol Życzkowski et al, Volume of the set of separable states, Physical Review A (2002). DOI: 10.1103/PhysRevA.58.883

Leonid Gurvits et al, Largest separable balls around the maximally mixed bipartite quantum state, Physical Review A (2002). DOI: 10.1103/PhysRevA.66.062311

Stanislaw J. Szarek, Volume of separable states is super-doubly-exponentially small in the number of qubits, Physical Review A (2005). DOI: 10.1103/PhysRevA.72.032304

Xi-Lin Wang et al, 18-Qubit Entanglement with Six Photons' Three Degrees of Freedom, Physical Review Letters (2018). DOI: 10.1103/PhysRevLett.120.260502

Comment by Dr. Krishna Kumari Challa on December 19, 2022 at 2:12pm

Gold-based passive heating for eyewear

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