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Researchers have found a way to use a component of glycerol to produce bio-based propylene.

A new study reveals that artificial intelligence chatbots, such as ChatGPT, may be almost as effective as consulting a doctor for advice on low back pain.

Astronomers have observed the atmosphere of a hot and uniquely inflated exoplanet using NASA's James Webb Space Telescope.

With strong bactericidal properties, graphene has the potential to become a game changer in the fight against antibiotic-resistant bacteria. So far there have been no efficient ways to control these properties -- and thus no way to make use of graphene's potential in healthcare. Now researchers have solved the problem by using the same technology found in an ordinary fridge magnet. The result of which, is an ultra-thin acupuncture-like surface that can act as a coating on catheters and implants -- killing 99.9 percent of all bacteria on a surface.

Ammonia (NH3) can be decomposed to produce hydrogen gas without releasing CO2. The ease of transport and high hydrogen density make it valuable for the green energy industry. A drawback of using NH3 is that it requires very high temperatures for decomposition reactions. Researchers have now presented a surface protonics-assisted method for the on-demand production of green hydrogen from ammonia using an electric field and Ru/CeO2 catalyst.

In most vertebrates, a pattern of chemical marks on the genome is a reliable indicator of age, but in axolotls this clock seems to stop after the first four years of life

New research is revealing that common sense is a lot more idiosyncratic than we thought, with important implications for tackling political polarisation and the future of AI

Artificial coastlines, including human-made dikes and other engineered constructions, can help prevent erosion and protect from storms and flooding. However, ecological functions remain unprotected from many of these structures. So researchers in China have investigated the use of specialized types of cement. The team started with a limestone and clay cement that hardens underwater and then added polyacrylamide and chitosan. The two treatments were mixed into the cement to form the hardened substrate, and they were sprayed onto previously hardened cement as a surface treatment. After two days, biofilm was found active and growing well on the surface-treated samples.

UPDATE: As Malgorzata points out in a comment below citing an Algemeiner article, Whitmer did defend her attorney general, which constitutes taking sides against the odious Rashida Tlaib. A quote from the Algemeiner:

Michigan Gov. Gretchen Whitmer (D) issued a statement in defense of the state’s Jewish Attorney General Dana Nessel over what she called “antisemitic” suggestions by US Rep. Rashida Tlaib (D-MI) that Nessel’s office harbored “biases” against pro-Palestinian activists.

“The suggestion that Attorney General Nessel would make charging decisions based on her religion as opposed to the rule of law is antisemitic,” Whitmer wrote on Monday. “Attorney General Nessel has always conducted her work with integrity and followed the rule of law. We must all use our platform and voices to call out hateful rhetoric and racist tropes.”

The statement came one day after Whitmer, during an interview with CNN anchor Jake Tapper, initially refused to weigh in on the quarrel between Nessel and Tlaib, who suggested that the attorney general has not treated anti-Israel protesters impartially because of her Jewish faith.

Whitmer, having corrected herself, is back on the side of the angels again. If only she were the Democratic candidate for President!

Although Gretchen Whitmer, the governor of Michigan, identifies herself as a “progressive” Democratic, to me she seems progressive in the right way: she’s trying to fix the problems in her state with tangible legislation. You can see the list of her accomplishments here, and A. B. Stoddard, writing in The Bulwark last year, called Whitmer 52, “one of the most experienced, exciting, and winning Democrats in the country.” I agree with nearly all of her policies—although she’s a bit too soft on illegal immigration—and that’s why I wanted Whitmer to be the Democratic candidate for President. (Importantly, she also governs a swing state.) She has accomplished stuff in a bipartisan climate, and I’d feel a lot better with her at the helm than with Kamala Harris.

But when Kamala Harris was anointed by the Democratic Party to be its candidate, Whitmer refused to be a candidate. That’s very sad, because, given her record, Harris doesn’t hold a candle to her.  And, of course, if Harris wins this time she’ll surely be the Democratic candidate in 2028 unless she screws up big time, so that Whitmer would have to wait eight more years if she wanted to run America.

So I was sad to see this article in Politico; the title tells the tale (click to read):

An excerpt:

Michigan Gov. Gretchen Whitmer declined to take sides in a debate between Michigan Attorney General Dana Nessel and Rep. Rashida Tlaib (D-Mich.) over almost a dozen University of Michigan students charged for pro-Palestinian protests.

“I’m not going to get in the middle of this argument that they’re having,” Whitmer said on Sunday in an interview with Jake Tapper on CNN’s “State of the Union.”

“I can just say this. We do want to make sure that students are safe on our campuses and we recognize that every person has the right to make their statement about how they feel about an issue, a right to speak out,” Whitmer added. “And I’m going to use every every lever of mine to ensure that both are true.”

Nessel, Michigan’s first Jewish Attorney General, recently charged 11 University of Michigan students for pro-Palestinian demonstrations. Most were charged for refusing to vacate the encampments on campus in May, according to the Detroit Metro Times.

Nessel defended the state’s decision to charge these students saying, “Conviction in your ideals is not an excuse for violations of the law” and “what is a crime anywhere else in the city remains a crime on university property.”

Tlaib — the only Palestinian American in Congress and a strong critic of Israel — criticized Nessel for this decision in an interview with the Detroit Metro Times. She said: “It seems that the attorney general decided if the issue was Palestine, she was going to treat it differently, and that alone speaks volumes about possible biases within the agency she runs.”

. . . When CNN’s Jake Tapper initially asked about the back and forth between Nessel and Tlaib, Whitmer declined to directly defend or criticize the state’s attorney general, responding that all she could say was “our Jewish community is in pain, as is our Palestinian and Muslim and Arab communities in Michigan.”

“I know that seeing the incredible toll that this war has taken on both communities has been really, really challenging and difficult. And my heart breaks for so many,” Whitmer said. “But as governor, my job is to make sure that both these communities are protected and respected under the law in Michigan. And that’s exactly what I’m going to stay focused on.”

Well, it seems to me that Whitmer should be supporting her own attorney general, or at least saying, that “Nessel brought charges against the protesters and we need to let those charges play out in the legal system”. But she went a bit further with her “whataboutism”, not recognizing, apparently, that free speech is not the same thing as disrupting a campus and violating the law.

That said, Whitmer is clearly between a rock and a hard place. While her attorney general brought charges against pro-Palestinian students, one of her state’s representatives, the odious Tlaib, is supported by many Michigan Palestinians or their supporters. So I can’t hold this against her very hard. While I dislike politicans that are pure pragmatists, Whitmer is not really a pragmatist.  She takes stands, and is known for her potty mouth, which I like.  A bit of that is evident in the video below.

Here’s her speech at the Democratic National Convention, without any nattering about coconuts or inappropriate laughter.  Whitmer of course had to support Harris in her speech, but believe me, I’d rather check a box for Whitmer than for Harris in November.  Had there been debates to choose a candidate, Whitmer would, I think, have come out on top.  This is a tough, accomplished women who has no problem articulating her positions.

As promised, the audiobook for Waves in an Impossible Sea, read by Christopher Grove, has finally come available. You can find it on Audible and on many other platforms. (Click here to order the audibook, hardback, or e-book.)

To help make the text easier to follow, I’ve put the 50+ figures, the 6 tables, and the glossary on-line. You might, for instance, choose to have them open on your phone for easy reference while you’re listening. (The endnotes are also there too, although my understanding is that Mr. Grove won’t be mentioning them as he reads, so you may need the text to make them useful.)

There are additional resources for readers already up on this website, supplementing the book, and more are coming soon, so please make use of them. Also feel free to ask me questions if you find yourself confused — and please don’t be embarrassed to do so, because the universe is confusing… even to physicists. No question is too simple; in fact, the simple ones (what is empty space? what’s a particle? why don’t we feel the Earth’s motion?) are often the hardest to answer.

When we talk about reducing carbon release in order to slow down and hopefully stop anthropogenic global warming much of the focus is on the energy and transportation sectors. There is a good reason for this – the energy sector is responsible for 25% of greenhouse gas (GHG) emissions, while the transportation sector is responsible for 28% (if you separate out energy production and not include it in the end-user category). But that is just over half of GHG emissions. We can’t ignore the other half. Agriculture is responsible for 10% of GHG emissions, while industry is responsible for 23%, and residential and commercial activity 13%. Further, the transportation sector has many components, not just cars and trucks. It includes mass transit, rail, and aviation.

Any plan to deeply decarbonize our civilization must consider all sectors. We won’t get anywhere near net zero with just green energy and electric cars. It is tempting to focus on energy and cars because at least there we know exactly what to do, and we are, in fact, doing it. Most of the disagreement is about the optimal path to take and what the optimal mix of green energy options would be in different locations. For electric vehicles the discussion is mostly about how to make the transition happen faster – do we focus on subsidies, infrastructure, incentives, or mandates?

Industry is a different situation, and has been a tough nut to crack, although we are making progress. There are many GHG intensive processes in industry (like steel and concrete), and each requires different solutions and difficult transitions. Also, the solution often involves electrifying some aspect of industry, which works only if the energy sector is green, and will increase the demand for clean energy. Conservative estimates are that the energy sector will increase by 50% by 2050, but if we are successful in electrifying transportation and industry (not to mention all those data centers for AI applications) this estimate may be way off. This is yet another reason why we need an all-of-the-above approach to green energy.

Let’s focus on agriculture and aviation, which are also considered difficult  sectors to decarbonize, starting with agriculture. Often the discussion on agriculture focuses on meat consumption, because the meat industry is a very GHG intensive portion of the agricultural sector. There is a good argument to be made for moderating meat consumption in industrialized nations, both from a health and environmental perspective. This doesn’t mean banning hamburgers, and it is often strawmanned, but some voluntary moderation would be a good thing. There is also some mitigation possible – yes, I am talking about capturing cow farts.

There are also efforts to shift farming from a net carbon emitter to a net carbon sequester. A recent analysis finds that this is plausible, by switching to certain farming practices that could be a net financial benefit to farmers and help maintain farming productivity in the face of warming. This includes the use of cover crops, combining farming with forestry, and using no-till methods of farming. With these methods farms can turn into a net carbon sink.

Obviously this is a temporary mechanism, but could help buy us time. Right now we are doing the opposite – cutting down forest to convert to farmland, and eliminating carbon sinks. Farming forests, or incorporating more trees into farmland, can help reverse this process.

What about aviation? This is also a difficult sector, like industry, because we don’t have off-the-shelf solutions ready to go. A recent report, however, outlines steps the industry can take over the next five years that can put it on track to reach net zero by 2050. One step, which I had not heard of before, is deploying a global contrail avoidance system. Contrails are vapor trails that form when the hot jet exhaust mixes with cool moist air. These act like artificial cirrus clouds, which have a mild cooling effect during the day but a much more significant warming effect at night (by trapping heat). Contrails are responsible for 35% of the aviation industry’s warming effect. Using AI and satellite data, pilots can be directed to routes that would minimize contrail formation.

They also recommend system-wide efficiency strategies, which they find can halve fuel burn from aviation by 2050. That seems incredible, but they argue that there are efficiencies that individual companies are unable to address, but that can be achieved with system wide policies.

The next point is a bit more obvious – switching to sustainable aviation fuel (SAF). This mostly means making jet fuel from biomass. They mostly recommend policy changes that will help the industry rapidly scale up biofuel production from biomass. That’s really the only way to decarbonize jet travel. Hydrogen will never be energy dense enough for aviation.

We are on the verge of seeing commercial electric planes, mainly because of advances in battery technology. These could fill the regional service and small city routes, with ranges in the 300-400 mile zone (and likely to increase as battery technology continues to advance). Not only would an electric plane industry replace current fossil-fuel burning regional flights, but they could expand the industry and displace other forms of travel. Many more people may choose to take a quick flight from a regional airport than drive for 8 hours.

Their last recommendation is essentially a roll of the dice: “Launching several moonshot technology demonstration programmes designed to rapidly assess the viability and scalability of transformative technologies, bringing forward the timeline for their deployment.”

This sounds partly like an admission that we don’t currently have all the technology we would need to fully decarbonize aviation. Maybe they consider this to be not absolutely necessary but a good option. In any case, I am always in favor of supporting research in needed technology areas. This has generally proven to be an investment worth making.

As is often the case, this all looks good on paper. We just have to actually do it.

The post Decarbonizing Aviation and Agriculture first appeared on NeuroLogica Blog.

High-temperature superconducting cables that could transform the power grid may be increasingly viable, thanks to a side effect of fusion energy research and new ways to cool the wires

Fifteen trivia questions from previous aviation themed episodes of Skeptoid.

A research team has developed a low-cost iron chloride cathode for all-solid-state lithium-ion batteries, which could significantly reduce costs and improve performance for electric vehicles and large-scale energy storage systems.

Noctilucent clouds were once thought to be a fairly modern phenomenon. A team of researcher have recently calculated that Earth and the entire Solar System may well have passed through two dense interstellar clouds causing global noctilucent clouds that may have driven an ice age. The event is thought to have happened 7 million years ago and would have compressed the heliosphere, exposing Earth to the interstellar medium. 

Interstellar clouds are vast regions of gas and dust that flat between the stars inside galaxies. They are mostly made up of hydrogen along with a little helium and trace elements of heavier elements. They are a key part of the life circle of stars providing the materials for new stars to be formed and are seeded with elements after stars die. The clouds vary significantly in size, density and location and are an important part of the evolution of the Galaxy.

An annotated illustration of the interstellar medium. The solar gravity lens marks the point where a conceptual spacecraft in interstellar space could use our sun as a gigantic lens, allowing zoomed-in close-ups of planets orbiting other stars. Credits: Charles Carter/Keck Institute for Space Studies

Earth’s journey around the Galaxy is not for the impatient for it takes about 250 million years to complete one full orbit at a speed of 828,000 kilometres per hour. Currently the Solar System is located in the Orion Arm, one of the spiral arms of our Galaxy. During the journey, Earth travels through different regions, encountering stars and different densities of the interstellar medium. It experiences gravitational interactions with nearby stars and nebula sometimes exerting  subtle interactions. Regardless of the immense journey, the stars of our Galaxy remain relatively unchanged over a human lifetime. 

The Milky Way is a spiral galaxy with several prominent arms containing stellar nurseries swathed in pink clouds of hydrogen gas. The sun is shown near the bottom in the Orion Spur. Credit: NASA

A team of astronomers let by Jess A. Miller from the Department of Astronomy of Boston University have traced the path of the Sun back through time. In doing so, they have identified two occasions when the Earth and Solar System passed through two dense interstellar clouds. One of the crossings occurred 2 million years ago, the other 7 million years ago. Exploring the properties of the clouds, the team assert that the clouds are dense enough that they could compress the solar wind to inside the orbit of Earth. 

The Solar Wind is a constant stream of charged particles, mostly electrons and protons that are emitted from the upper layer of the Sun’s atmosphere, the corona. The particles travel through the Solar System at speeds between 400 and 800 kilometres per second. The edge of our Solar System is defined as the point where the solar wind merges with the interstellar medium.

A composite image comprised of the Sun’s surface, corona, and digitally-added coronal loops rendered by Andrew McCarthy. (Credit: Andrew McCarthy)

Previous teams have analysed climate change events due to these interstellar medium interactions with similar findings. Global cooling has been the result with an ice age being triggered. The study by Miller and team have readdressed this very topic using modern technology and processes. 

The team find that the interactions have indeed played a part in changes to the atmosphere of Earth. They find that levels of hydrogen in the upper atmosphere would have increased substantially. The newly acquired hydrogen would be converted to water molecules in the lower atmosphere and it would also have led to a reduction in mesospheric levels of ozone. These processes would have led to the appearance of global noctilucent clouds in the mesosphere. They would not have been permanent but may have blocked 7% of sunlight from reaching Earth, plunging our planet into an ice age.

Source : Earth’s Mesosphere During Possible Encounters With Massive Interstellar Clouds 2 and 7 Million Years Ago

The post What Happens to the Climate When Earth Passes Through Interstellar Clouds? appeared first on Universe Today.

Researchers find certain biosignature molecules may not indicate life is present, contrary to popular thought.

Earth’s last half-billion years were action-packed. During that time, the climate underwent many changes. There have been changes in ocean levels and ice sheets, changes in the atmosphere’s composition, changes in ocean chemistry, and ongoing biological evolution punctuated with extinction events.

A record of Earth’s temperature over the last 485 million years is helping scientists understand how it all played out and illustrating what could happen if we continue to enrich the atmosphere with carbon.

The new temperature record is presented in research titled “A 485-million-year history of Earth’s surface temperature.” It’s published in Science, and the lead author is Emily Judd. Judd is from the Department of Paleobiology at the Smithsonian National Museum of Natural History.

“This research illustrates clearly that carbon dioxide is the dominant control on global temperatures across geological time.”

Jessica Tierney, University of Arizona

The new historical temperature comes from an effort named PhanDA, which stands for Phanerozoic Data Assimilation. PhanDA combined data from climate models with data from geology to determine how the climate has changed over the last nearly 500 million years. The Phanerozoic is Earth’s current geological eon, and it started 538.8 million years ago. It’s known for the proliferation of life, and its beginning is marked by the appearance of the hard shells of animals in the fossil record.

PhanDA is a mix of data and prior simulations by the scientific community. “This approach leverages the strengths of both proxies and models as sources of information, providing an innovative way to explore the temporal and spatial patterns in Earth’s climate across the Phanerozoic,” the researchers write in their paper. It allowed the researchers to reconstruct the climate more thoroughly.

This figure illustrates the data used to create PhanDA. A shows the temporal distribution of proxy data used in PhanDA. B shows the spatial distribution. C shows the range (gray band) and median (black line) of GMSTs within the prior model ensemble for each assimilated stage. Image Credit: Judd et al. 2024.

“This method was originally developed for weather forecasting,” said Judd. “Instead of using it to forecast future weather, here we’re using it to hindcast ancient climates.”

We’re blowing by atmospheric carbon benchmarks, and the Earth is warming. We’re now at over 420 ppm of CO2. The best way to understand what’s coming our way is by looking at the past.

“If you’re studying the past couple of million years, you won’t find anything that looks like what we expect in 2100 or 2500,” said co-author Scott Wing, the curator of paleobotany at the National Museum of Natural History. Wing’s research focuses on the Paleocene–Eocene Thermal Maximum, a period of dramatic global warming 55 million years ago. “You need to go back even further to periods when the Earth was really warm, because that’s the only way we’re going to get a better understanding of how the climate might change in the future.”

During the Paleocene-Eocene Thermal Maximum (PETM), a massive amount of carbon was emitted into the atmosphere and the oceans. The Earth’s temperature reacted swiftly, warming by between five and eight degrees Celsius in only a few thousand years. While a few thousand years might seem long compared to a human lifetime, it’s nearly instantaneous for the climate of an entire planet. It likely triggered the massive extinction of between 35% to 50% of benthic life. Fossils show that during this time, sub-tropical planets grew in the polar regions.

Many scientists think the PETM is the best analogue for what we’re facing today. No matter what we do with our emissions in the next several decades, much of the carbon humanity has released into the atmosphere since the Industrial Revolution will persist in the atmosphere for thousands of years.

Earth’s reconstructed Global Mean Surface Temperature for the past 485 million years. Blue rectangles show the maximum latitudinal ice extent, and orange dashed lines show the timing of the five major mass extinctions of the Phanerozoic. The five orange fishbone symbols mark mass extinctions. Image Credit: Judd et al. 2024.

PhanDA illustrates the unbreakable link between carbon and global warming. According to co-author Jessica Tierney, a paleoclimatologist at the University of Arizona, the link between the climate and carbon is undeniable. “This research illustrates clearly that carbon dioxide is the dominant control on global temperatures across geological time,” said Tierney. “When CO2 is low, the temperature is cold; when CO2 is high, the temperature is warm.”

While proof of the link between climate and carbon isn’t new, this long timeframe drives it home. “The consistency of this relationship is surprising because, on this timescale, we expect solar luminosity to influence climate,” the authors write. “We hypothesize that changes in planetary albedo and other greenhouse gases (e.g., methane) helped compensate for the increasing solar luminosity through time.”

Overall, Earth’s global mean surface temperature (GMST) ranged from 11° to 36°C during the Phanerozoic, a larger range than previously thought. It also shows that greenhouse climates were hotter than thought. The largest temperature swings were in the high latitudes, but tropical temperatures ranged from 22 C to 42 C. This goes against the idea that the tropics have a fixed upper limit and shows that life must have evolved to survive in those higher temperatures.

The research also shows that our current climate is actually cooler than the climate through most of the Phanerozoic. Technically, Earth is in an ice age right now, though the ice is receding and has been for thousands of years. Earth’s current GMST is 15 Celsius, lower than during most of the Phanerozoic.

But while that may sound comforting, it’s not. It’s the rate of change in the GMST that’s dangerous. Our GHG emissions are warming the planet faster than at any time during the Phanerozoic.

“Humans, and the species we share the planet with, are adapted to a cold climate,” Tierney said. “Rapidly putting us all into a warmer climate is a dangerous thing to do.”

This figure from the published research shows the climate states through the Phanerozoic. D shows the latitudinal surface air temperature gradient associated with each of the climate states. Coloured bands show the 16th to 84th percentiles, and coloured lines show the median value. Image Credit: Judd et al. 2024.

While PhanDA is generally in agreement with previous climate reconstructions, it deviates in some ways. For example, cold climate periods don’t always coincide with glaciation and ice ages. Earth’s surface is ever-changing, and that can make some conclusions difficult to reach. “Many of the traditional glacial indicators can have nonglacial origins, complicating the interpretation of the rock record, and limited outcrop of older rocks and poor age control can make it difficult to discern between isolated alpine glaciers and widespread ice sheets,” the authors explain.

But that doesn’t take much away from PhanDA. It strengthens our understanding of climate and carbon.

This figure illustrates the undeniable relationship between atmospheric carbon and a warming climate. B shows PhanDA GMST versus CO2, colour-coded by geologic era. The black dashed line shows the York regression, a statistical method used to draw a straight line between data points with some uncertainties. C shows the CO2 ranges for each of the defined climate states. Image Credit: Judd et al. 024.

Shockingly, the work suggests that Earth’s climate is even more sensitive to CO2 than some current models show.

“PhanDA GMST exhibits a strong relationship with atmospheric CO2 concentrations, demonstrating that CO2 has been the dominant force controlling global climate variations across the Phanerozoic,” the authors write in their conclusion.

The post From Frozen to Sweltering: Earth’s Climate Over the Last 485 Million Years appeared first on Universe Today.

Archaeologists have used AI to discover hundreds of large-scale drawings depicting figures like llamas, decapitated human heads and killer whales armed with knives

Engineers have designed an innovative tubular structural system that can be packed flat for easier transport and pop up into strong building materials. This breakthrough is made possible by a self-locking system inspired by curved-crease origami -- a technique that uses curved crease lines in paper folding.

Scientists who arranged for 48 human bioengineered heart tissue samples to spend 30 days at the International Space Station report evidence that the low gravity conditions in space weakened the tissues and disrupted their normal rhythmic beats when compared to earth-bound samples from the same source.