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Comment by Dr. Krishna Kumari Challa 3 hours ago

In their new study, the scientists look at the dense environment of dusty disks, from which a new solar system with a star and planets emerges eventually. Such disks form when clouds suddenly collapse under the force of gravity. In this environment, water molecules are much more prevalent—forming ice on the surface of any growing agglomerates of particles that could inhibit the reactions that form peptides.

By emulating the reactions likely to occur in the interstellar medium in the laboratory, the study shows that, although the formation of peptides is slightly diminished, it is not prevented. Instead, as rocks and dust combine to form larger bodies such as asteroids and comets, these bodies heat up and allow for liquids to form. This boosts peptide formation in these liquids, and there's a natural selection of further reactions resulting in even more complex organic molecules. These processes would have occurred during the formation of our own solar system.

Many of the building blocks of life such as amino acids, lipids and sugars can form in the space environment. Many have been detected in meteorites.

Because peptide formation is more efficient in space than on Earth, and because they can accumulate in comets, their impacts on the early Earth might have delivered loads that boosted the steps towards the origin of life on Earth.
So what does all this mean for our chances of finding alien life? Well, the building blocks for life are available throughout the universe. How specific the conditions need to be to enable them to self-assemble into living organisms is still an open question. Once we know that, we'll have a good idea of how widespread, or not, life might be.

Serge A. Krasnokutski et al, Formation of extraterrestrial peptides and their derivatives, Science Advances (2024). DOI: 10.1126/sciadv.adj7179

Part 3

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Comment by Dr. Krishna Kumari Challa 3 hours ago

DNA, or deoxyribonucleic acid, comprises two long strands forming a double helix structure. Each strand is composed of smaller molecules called nucleotides. Every nucleotide contains three components: a sugar molecule (deoxyribose in DNA), a phosphate group, and a nitrogenous base. There are four types of nitrogenous bases in DNA: adenine (A), thymine (T), cytosine (C), and guanine (G). These bases pair specifically (A with T, C with G) to form the rungs of the double helix ladder, with the sugar and phosphate groups forming the backbone of the DNA molecule.

Peptides are an assemblage of amino acids in a short chain-like structure. Peptides can be made up of as little as two amino acids, but also range to hundreds of amino acids.

The assemblage of amino acids into peptides is an important step because peptides provide functions such as "catalyzing," or enhancing, reactions that are important to maintaining life. They are also candidate molecules that could have been further assembled into early versions of membranes, confining functional molecules in cell-like structures.

However, despite their potentially important role in the origin of life, it was not so straightforward for peptides to form spontaneously under the environmental conditions on the early Earth. In fact, the scientists behind the current study had previously shown that the cold conditions of space are actually more favourable to the formation of peptides.

In the very low density of clouds of molecules and dust particles in a part of space called the interstellar medium, single atoms of carbon can stick to the surface of dust grains together with carbon monoxide and ammonia molecules. They then react to form amino acid-like molecules. When such a cloud becomes denser and dust particles also start to stick together, these molecules can assemble into peptides.
Part 2

Comment by Dr. Krishna Kumari Challa 3 hours ago

Crucial building blocks of life on Earth can more easily form in outer space, says new research

The origin of life on Earth is still enigmatic, but we are slowly unraveling the steps involved and the necessary ingredients. Scientists think life arose in a primordial soup of organic chemicals and biomolecules on the early Earth, eventually leading to actual organisms.

It's long been suspected that some of these ingredients may have been delivered from space. Now a new study, published in Science Advances, shows that a special group of molecules, known as peptides, can form more easily under the conditions of space than those found on Earth. That means they could have been delivered to the early Earth by meteorites or comets—and that life may be able to form elsewhere, too.

The functions of life are upheld in our cells (and those of all living beings) by large, complex carbon-based (organic) molecules called proteins. How to make the large variety of proteins we need to stay alive is encoded in our DNA, which is itself a large and complex organic molecule.
However, these complex molecules are assembled from a variety of small and simple molecules such as amino acids—the so-called building blocks of life.

To explain the origin of life, we need to understand how and where these building blocks form and under what conditions they spontaneously assemble themselves into more complex structures. Finally we need to understand the step that enables them to become a confined, self-replicating system—a living organism.

This latest study sheds light on how some of these building blocks might have formed and assembled, and how they ended up on Earth.
Part 1

Comment by Dr. Krishna Kumari Challa yesterday

Haug and Spavieri estimate that a micro black hole battery weighing just one kilogram could provide "enough energy for a family for generations" – approximately 470 million times the energy of the most efficient 200-kilogram lithium battery that currently exists.

"While achieving such a level of technological advancement is certainly not imminent, it's not inconceivable that battery technology development could follow a trajectory similar to that of computer technology," Haug and Spavieri write.
The pair aren't the first team to suggest such a wild idea, which just goes to show the gravity (pun intended) of the energy transition we face, to power the world without burning fossil fuels that are cooking the planet.

Previous work has considered similarly small Schwarzschild black holes, but Haug and Spavieri reason the charged black holes described by the Reissner–Nordström metric are eight times more energy-dense.

Of course, whether such tiny, non-rotating black holes exist, or even be created in a practical setting, is a project for future imaginations.

"If we use strategically placed neutron stars as magnets, this would still require [a particle] accelerator around the size of the Solar System," Haug and Spavieri note. "This solution seems quite unrealistic, but never say never."

https://www.sciencedirect.com/science/article/pii/S1574181824000247...

Part 3

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Comment by Dr. Krishna Kumari Challa yesterday

In theory, oppositely charged micro black holes could then be brought together, one by one, leading them to merge into a single black hole that 'evaporates' very quickly into pure energy. The extracted energy wouldn't come from within the black hole, but just outside it: where gravity concentrates.
This mind-bending suggestion is not beyond the realms of possibility. Tiny, primordial black holes are thought to exist, but have never been detected – perhaps because they have radiated away most of their energy after forming in the primeval plasma that filled the Universe following the Big Bang.
But the prospect of 'micro black hole batteries' will more than likely remain purely hypothetical, saying more about how far trends in battery technology have to go than where we'll actually end up.

"Today's batteries are extremely inefficient compared to their ultimate potential, and we are likely just at the very beginning of a battery revolution," Espen Haug, a theoretical physicist and finance analyst at the Norwegian University of Life Sciences, and Gianfranco Spavieri, a physicist at the University of the Andes Venezuela, write in their published paper.
part 2

Comment by Dr. Krishna Kumari Challa yesterday

Physicists Say The Ultimate Battery Could Harness The Power of Black Holes

The quest to generate more energy from less material while avoiding burning any more fossil fuels than our planet can handle is spawning some, let's say, creative ideas.
Nuclear fusion records are being smashed, even if only by the tiniest of margins and seconds at a time. Meanwhile, solar panels are becoming increasingly efficient as expected and their installation – atop car parks and green roofs – is also more strategic, helping to reap bigger and bigger gains.
But how to store that energy and relinquish it on demand across the electricity grid remains a huge challenge, even if battery storage and manufacturing capacity are trending upwards, making prices plummet.

Theoretical scientists are a particularly imaginative bunch when it comes to projecting how those trends might play out or where innovation could take us, years into the future.

In the latest turn, two physicists have been pondering the ultimate theoretical limits of battery energy density, based on Einstein's general theory of relativity.

Starting with a strict interpretation of equations describing perfectly round masses that don't rotate, the pair describe the behavior of ideal models of microscopic black holes forming in a tight space jam-packed with energy. Thanks to the way these tiny monsters interact, the whole system could act somewhat like a nuclear reactor, freeing energy stored in the bonds of particles to generate enormous amounts of clean energy.

These black holes would need to be charged and tiny, just one Planck mass each, so that when bundled together into cells packed with similarly charged black holes, their electromagnetic repulsion offsets the pull of gravity, creating stable energy storage that doesn't gobble itself up. More massive black holes are also less energy-dense than tiny ones.
Part 1

Comment by Dr. Krishna Kumari Challa yesterday

To deepen their understanding of the impact of epistemic injustice—injustice around the domain of knowledge—the researchers focused on the emotional consequences of feedback. They modeled epistemic injustice in the lab by creating an experiment to safely simulate everyday experiences of invalidation. Participants observed a game, then shared their knowledge about the game—either how it worked or how they felt about it.

The crucial part of the experiment came next; participants received feedback, supposedly from their partner in the game, about what they shared. Some feedback was validating, some was discrediting, and some was mildly insulting.

The participants then rated how positive or negative that feedback made them feel, the key measure of their emotional responses. The researchers combined the experiment with surveys of variables thought to factor into epistemic injustice—race, gender and experiences with race-based discrimination and trauma.

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The experiment conducted by researchers revealed an important generality about knowledge. People find it more emotionally taxing to have their understanding of facts questioned than to have their feelings questioned.

But more important findings came from the experiment outcomes combined with the surveys, which showed that race and gender factored into the experimental results.

These findings are consistent, with research on prejudice and discrimination showing that Black men experience more racial discrimination in areas where credibility is extremely important—such as employment, educational settings and interactions with law enforcement—but where credibility can be undermined by emotional responses.

Another consistent finding underscored the importance of individual differences. Validation—when participants were told that they were right—was significantly more positive for white women compared with white men, which resonates with studies showing that positive interventions boost women's academic performance.

Insights from this study could benefit managers, educators and people interested in living and working in safer and more just communities. For universities, we think the results highlight the world of emotional coping mechanisms spoken about too rarely, but always under the surface in intellectual spaces.

Laura Niemi et al, The emotional impact of baseless discrediting of knowledge: An empirical investigation of epistemic injustice, Acta Psychologica (2024). DOI: 10.1016/j.actpsy.2024.104157

Part 2

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Comment by Dr. Krishna Kumari Challa yesterday

Persistent questioning of knowledge takes a toll: New study supports theories that baseless discrediting harms

It can be demoralizing for a person to work in a climate of repetitive skepticism and doubt about what they know, a new study shows.

This is  not about healthy, well-founded skepticism. This is about failures-of-exchange when a person is persistently overlooked, unheard, brushed off and explained to. 

Why? Something about who the person is—their identity—suggests to their interlocuter that they couldn't possibly be right due to the interlocuter's bias. These biases take many forms: race or ethnicity, manner of speaking, weight, attractiveness, age, style and so on.

Researchers have theorized that baseless discrediting of what people with marginalized social identities know is a central driver of prejudice and discrimination.

They conducted experiments that backed up these theories, finding that people are emotionally invested in being treated as credible, even in anonymous games. Further, they found that emotional impact of discreditation varies based on gender, race and experience with racial discrimination. 

The authors think that hostility in intellectual arenas is an ethical issue.

Discrediting of a person as a legitimate knower can be subtle, which makes it difficult to isolate, and, therefore, understudied.

But growing research shows regular exposure to even relatively subtle prejudice and discrimination degrades physical and mental health, leading to outcomes like high blood pressure, chronic stress and depression.

Part 1

Comment by Dr. Krishna Kumari Challa yesterday

(PS: Please take this work with a pinch of salt because we are waiting for reproduction of these results.

This is still under review and the point difference is small.

And, students, this is not an excuse for your laziness. Because this need not be the case every time you write your exams. Most of the time in my practical and viva part of exams I was the last person to submit my results and got interviewed but still got top ranks).

Zhihan (Helen) Wang et al, 30 Million Canvas Grading Records Reveal Widespread Sequential Bias and System-Induced Surname Initial Disparity (2023). On SSRN: ssrn.com/abstract=4603146

Part 4

Comment by Dr. Krishna Kumari Challa yesterday

Their research uncovered a clear pattern of a decline in grading quality as graders evaluate more assignments. According to Wang, students whose surnames start with A, B, C, D or E received a 0.3-point higher grade out of 100 possible points than compared to when they were graded randomly. Likewise, students with later-in-the-alphabet surnames received a 0.3-point lower grade—creating a 0.6-point gap.

A 0.6-point difference might seem small, but such a disparity did affect students' course grade-point averages, which negatively influences opportunities in their respective career paths.

The Researchers suspect that fatigue among the examiners is one of the major factors that is driving this effect, because when you're working on something for a long period of time, you get tired and then you start to lose your attention and your cognitive abilities are dropping.

The researchers note the option exists to grade the assignments in a random order, and some educators do, but alphabetical order is the default mode in Canvas and other online learning management systems. One simple fix would be to make random order the default setting.

They also suggest academic institutions could hire more graders for larger classes, distribute the workload among more people or train them to be aware of and lessen the bias while grading.

The study is under review by the journal Management Science and currently available as a working paper.

Part 3

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