Comment

Comment by Dr. Krishna Kumari Challa on October 9, 2024 at 7:40am

The other greenhouse gases warming the planet

While carbon dioxide, or CO₂, is the best known greenhouse gas, several others, including methane and nitrous oxide, are also driving global warming and altering the Earth's climate.

CO₂ accounts for about two-thirds of the warming attributed to greenhouse gases.

Methane, or CH4, is the second most important greenhouse gas linked to human activity after CO2.

Around 40 percent of methane comes from natural sources, notably wetlands, but the majority (around 60 percent) is linked to human activities such as agriculture (ruminant breeding and rice cultivation), fossil fuels and waste. Its warming power is more than 80 times greater over 20 years than that of CO2, but its lifespan is shorter, making it an important lever in attempts to limit global warming in the short term.

Reducing methane emissions "would have a strong short-term cooling effect, because atmospheric methane concentrations would drop quickly.

Policies should "focus on capturing the low hanging fruit, so the very low-cost measures such as reducing natural gas leaks", say the experts.

Despite a global commitment to reduce planet-heating emissions signed by many countries, including the European Union and the United States, the trend is not positive.

Methane is rising faster in relative terms than any major greenhouse gas and is now 2.6-fold higher than in pre-industrial times.

Nitrous oxide, or nitrous protoxide (N2O), is the third major greenhouse gas and almost 300 times more potent than CO2.
It is mainly emitted by synthetic nitrogen fertilizers and manure used in agriculture.

Other emissions come from human activities (the chemical industry, wastewater, fossil fuels) or natural sources (the soil and oceans).
Part 1

Comment by Dr. Krishna Kumari Challa on October 9, 2024 at 6:59am

Using the toolkit of non-equilibrium quantum thermodynamics, the team has successfully bridged the gap between Aristotle's observations from two millennia ago and our modern understanding of quantum mechanics.

And it now opens the door to many research and applications-related questions.
The question forced the researchers to ask several fundamental questions about the relationship between the laws of thermodynamics that describe cooling, and the quantum mechanics, which describe reality at the fundamental level. We are currently developing a geometrical approach to the problem, which will hopefully allow us to understand different types of Mpemba effect in the same mathematical framework.
What you actually have in this really 'cool' Mpemba effect is a way to speed up cooling—and the cooling of quantum systems is absolutely vital for applications in quantum technologies.
Some of the tools the researchers are developing to investigate this fundamental effect will be of paramount importance for understanding things like heat flows, and how to minimize dissipation in future technologies.

Mattia Moroder et al, Thermodynamics of the Quantum Mpemba Effect, Physical Review Letters (2024). DOI: 10.1103/PhysRevLett.133.140404. On arXiv: DOI: 10.48550/arxiv.2403.16959

Part 3

**

Comment by Dr. Krishna Kumari Challa on October 9, 2024 at 6:56am

The 'Mpemba effect' gets its name from Erasto Mpemba who, as a school kid in 1963, was making ice cream in his home economics class in Tanzania. Mpemba did not wait for his hot ice cream mixture to cool before putting it directly in the fridge and was unsurprisingly puzzled to find that it froze before all the colder samples of his classmates.
He pointed this out to his teacher, who ridiculed him for not knowing his physics—Newton's law of cooling, for example, tells us that the rate at which an object cools is proportional to the temperature difference between the object and its surroundings. However, Mpemba convinced a visiting professor—Denis Osoborne from the University of Dar es Salaam—to test what he had seen and the pair published a paper that indeed evidenced the strange effect.
While the Mpemba effect is still not wholly understood—its presence is hotly debated at the macroscopic scale—it is much more apparent on the microscopic scale, where physicists use the theory of quantum mechanics to describe nature.

The quantum Mpemba effect has recently become a trending topic, but myriad questions hung in the air; for example, how does the quantum effect relate to the original effect? And can we construct a thermodynamic framework to understand the phenomenon better?
The QuSys research group's breakthrough answers some of the key questions.
Part 2

Comment by Dr. Krishna Kumari Challa on October 9, 2024 at 6:55am

Physics team uncovers a quantum Mpemba effect with a host of 'cool' implications

Initially investigating out of pure curiosity, researchers have made a discovery that bridges the gap between Aristotle's observations two millennia ago and modern-day understanding, while opening the door to a whole host of "cool"—and "cooling"—implications.

The Mpemba effect is best known as a perplexing phenomenon, where hot water freezes faster than cold water. Observations of the counter-intuitive effect date back to Aristotle who, over 2,000 years ago, noted that the Greeks of Pontus were exploiting the effect in their fishing practices.

And now, we can say that this strange effect is much more ubiquitous than we previously expected. Researchers have  just published a research paper in the journal Physical Review Letters  on the subject. The paper outlines their breakthrough in understanding the effect in the very different—and extremely complex—world of quantum physics.

Part 1

Comment by Dr. Krishna Kumari Challa on October 9, 2024 at 6:47am

When it comes to emergency care, ChatGPT overprescribes!

If ChatGPT were cut loose in the Emergency Department, it might suggest unneeded X-rays and antibiotics for some patients and admit others who didn't require hospital treatment, a new study from  has found.

The researchers said that, while the model could be prompted in ways that make its responses more accurate, it's still no match for the clinical judgment of a human doctor.

This is a valuable message to clinicians not to blindly trust these models.

ChatGPT can answer medical exam questions and help draft clinical notes, but it's not currently designed for situations that call for multiple considerations, like the situations in an emergency department.

 Chris Williams et al, Nature Communications (2024). www.nature.com/articles/s41467-024-52415-1

Comment by Dr. Krishna Kumari Challa on October 9, 2024 at 6:29am

Nobel Prize in physics awarded to 2 scientists for discoveries that enabled machine learning

Two pioneers of artificial intelligence—John Hopfield and Geoffrey Hinton—won the Nobel Prize in physics Tuesday for helping create the building blocks of machine learning that is revolutionizing the way we work and live.

 These two gentlemen were really the pioneers. The artificial neural networks—interconnected computer nodes inspired by neurons in the human brain—the researchers pioneered are used throughout science and medicine and "have also become part of our daily lives.

There are enormous benefits, its rapid development has also raised concerns about our future. Collectively, humans carry the responsibility for using this new technology in a safe and ethical way for the greatest benefit of humankind, the Nobel committee says.

 www.nobelprize.org/prizes/phys … dvanced-information/

Comment by Dr. Krishna Kumari Challa on October 8, 2024 at 12:55pm

Researchers found fuel-producing microbes that eat carbon monoxide—a highly toxic, flammable gas that is generated, among other things, during steel production. Currently, the steel industry produces approximately 2 billion tons of steel per year, and carbon monoxide comprises between 20% and 30% of their waste gases. That waste carbon monoxide is currently burned to produce carbon dioxide. It is less toxic, but still quite harmful. However, carbon monoxide-consuming microbes could turn these vast quantities of waste gas into green fuel.
Some carbon monoxide-consuming microbes can produce ethanol, a biofuel that has already been blended into normal fuels for several decades to make them a bit greener.

https://theconversation.com/meet-the-microbes-that-transform-toxic-...

Part 2

**

Comment by Dr. Krishna Kumari Challa on October 8, 2024 at 12:52pm

The microbes that transform toxic carbon monoxide into valuable biofuel

Microbes live everywhere, in enormous numbers. We might not see them with the naked eye, but they are in soils, lakes, oceans, hydrothermal vents, our homes, and even in and on our own bodies. And they don't just hang out there. They are always eating. Altogether, they eat so much that they influence the elemental cycles of the entire planet. 

Many of the microbes living on our planet do their utmost to keep these elemental cycles running in perfect balance. The fact of the matter is, though, that human interventions have significantly shifted the balance of more than one of them.
That sounds rather grim—and in part it is. It is time for a change. The key to change might lie in the simple trait that we share with every living organism on Earth. Everything needs food, from the microscopically small to the biggest blue whales. For microbes, food can include pretty much anything. Some microbes feed on apples; others prefer milk sugars (lactose) and help us make yogurt and cheese; and many, many microbes like the taste of waste.

This is extremely handy when it comes to cleaning our sewage water, for example. Billions of microbes in wastewater treatment plants happily gobble up all the nutrients in the water that's flushed down our drains. This reduces our risk of getting sick and helps improve surface water quality. Pretty amazing, right?

Some microbes on our planet can turn their food into our fuels. They, too, feed on waste.

Part 1

Comment by Dr. Krishna Kumari Challa on October 8, 2024 at 12:45pm

MicroRNAs are particularly promising for fighting cancer because some of these switches act as a tumor suppressor, so they put a brake on cells dividing inappropriately.
Because many viruses use microRNAs, several antiviral drugs are at varying stages of development, including for hepatitis C.

One complicating factor has been that microRNAs can be unstable.

But scientists also hope they can be used as a test called a "biomarker", which could reveal what type of cancer a patient could be suffering from, for example.
It also appears probable that microRNAs could be involved in the evolution of our species.
Part 2

Comment by Dr. Krishna Kumari Challa on October 8, 2024 at 12:44pm

What is microRNA? 

The Nobel Prize in Medicine was awarded on Monday to two US scientists for discovering microRNA, a previously unknown type of genetic switch which is hoped can pave the way for new medical breakthroughs.

But while several treatments and tests are under development using microRNAs against cancer, heart disease, viruses and other illnesses, none have actually yet reached patients.

And the world paid little attention when the new Nobel laureates Victor Ambros and Gary Ruvkun revealed their discovery decades ago, thinking it was just "something weird about worms".

How exactly these tiny genetic switches work inside our bodies?

Each cell in the human body has the same set of instructions, called DNA. Some turn into brain cells, while others become muscles.

So how do the cells know what to become? The relevant part of the DNA's instructions is pointed to via a process called gene regulation.

Ribonucleic acid (RNA) normally serves as a messenger. It delivers the instructions from the DNA to proteins, which are the building blocks of life that turn cells into brains—or muscles.

A good example  is the messenger RNA vaccines rolled out against COVID-19 during the pandemic, which insert a message with new instructions to build proteins that block viruses.

But the two new Nobel winners Ambros and Ruvkun discovered a whole new type of gene regulator that had previously been overlooked by science.

Rather than being the messenger which relays information, microRNA instead acts as a switch to turn other genes off and on.

This was a whole new level of control that we had totally missed.

The discovery of microRNAs brought an additional level of complexity by revealing that regions that were thought to be non-coding play a role in gene regulation.

Part 1

• ‹ Previous
• 1
• …
• 113
• 114
• 115
• 116
• 117
• …
• 1063
• Next ›
• Page