Musings: 2025 (current posts)

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Musings: 2025 (current posts)

Musings is an informal newsletter mainly highlighting recent science. It is intended as both fun and instructive. See the Introduction, listed below and in the navigation bar at the top, for more information.

In mid-2023, Musings transitioned to a new format, for a semi-retirement phase. With some adjustments, it is now similar to the earlier "briefly noted" format. The format is flexible, and contributions can be in various formats by agreement.

If you got here from a search engine... Do a simple text search of this page to find your topic. Searches for a single word (or root) are most likely to work.

   Introduction (separate page).
This page:
Current posts -- 2025
   New items
   March    February    January

Older items are on the archive pages, listed below.

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New items

The choano-mouse: implications for understanding the origins of transcription factors that control stem cells

April 23, 2025

Differentiated cells from a mammal can be induced into a stem cell state by a procedure involving adding key transcription factors. Those factors for making induced pluripotent stem cells (iPSC) include the proteins Sox and POU.

Choanoflagellates ("choanos", for short) are single-celled organisms thought to be very near the base of the animal kingdom. Choanos contain proteins recognizable as Sox and POU.

A recent article explores how close the choano Sox and POU are to their mouse counterparts. The most dramatic result is that choano Sox can fully substitute for mouse Sox in making mouse iPSC. Mice, apparently normal, have developed from iPSC made using choano Sox. The conclusion, then, is that at least one protein key to making stem cells existed before there were animals.

As a variation, the scientists calculated the likely sequence of the Sox protein that would have occurred "back then", in choanos prior to the emergence of animals. That predicted ancestral Sox also worked fine.

The situation for POU was more complex. The choano POU did not work in the induction of mouse iPSC.

It is a fascinating study, providing some clues about the origin of animal stem cells. I do suggest caution in interpreting what it all means.

* News stories:
- A Journey back in time to the origin of stem cells -- Proteins that regulate animal stem cells are much older than animals themselves. (Max Planck Institute for Terrestrial Microbiology, Marburg, November 15, 2024.)
- Scientists Created a Chymeric Mouse Using Billion-Year-Old Genes That Predate Animals -- A mouse was born using prehistoric genes and the results could transform regenerative medicine. (Tibi Puiu, ZME Science, April 3, 2025.)
* The article (open access): The emergence of Sox and POU transcription factors predates the origins of animal stem cells. (Ya Gao et al, Nature Communications 15:9868, November 14, 2024.)

A post about Sox: The role of the immune system in making stem cells (February 8, 2013).

A recent post about iPSC: Briefly noted... Making male and female stem cells from one person (January 11, 2023).

A post about choanoflagellates: Bacteria induce simple "pre-animal" to become colonial (September 8, 2012).

This post is listed on my BITN page Cloning and stem cells under Posts in my Musings newsletter. That section includes two extensive lists of related Musings posts. Another section of that page, Induced pluripotent stem cells (iPSC), includes background about iPSC.

How polar bears keep their fur free of ice

April 16, 2025

Polar bears swim in the cold waters of the Arctic. When they get out of the water, they may be exposed to sub-freezing air temperatures. Their wet fur should freeze up with ice. It doesn't. In fact, the fur doesn't even seem very wet.

The basic phenomenon has long been known. Now, a team of scientists has looked at how polar bears prevent icing of their fur. They grease their hair.

In some sense, that is not a new idea. Most mammals secrete an oily mixture called sebum. What's special here is the chemical composition of polar bear sebum. Ice adheres quite poorly to naturally greased polar bear fur. That property can be demonstrated in lab studies, not requiring a bear. (For example, washing the fur, thus removing the oily coating, allows ice to stick.)

It's a nice story about how polar bears cope with their environment. The authors also suggest that what they learned about anti-icing in polar bears could have a useful spin-off. The role of polar bear sebum is something like the role of Teflon in making non-stick surfaces. Teflon is falling out of favor, as we become concerned about the persistence of the polyfluorinated Teflon-related chemicals -- now sometimes referred to as "forever chemicals". Is it possible that the study of polar bear sebum could lead to better ski skins?

* News story: Bad hair bears! Greasy hair gives polar bears fur with anti-icing properties. (Science Daily (Trinity College Dublin), January 29, 2025.)
* The article (open access): Anti-icing properties of polar bear fur. (Julian Carolan et al, Science Advances 11:eads7321, January 29, 2025.)

More about polar bears: Staying warm -- polar-bear style (July 23, 2019).

More about "forever chemicals": Getting rid of "forever chemicals" (perfluorinated organic acids) (October 25, 2022).

Can we make a vaccine cream by exploiting an unusual immune response to harmless bacteria on the skin?

April 9, 2025

Just rub the vaccine cream on the arm. No pain. No trained medical personnel needed. Probably fewer side effects.

The problem is that things on the skin usually do not generate an immune response. They must penetrate. A new article reports exploiting one of the exceptions to make a vaccine cream.

The special situation here involves the bacterium Staphylococcus epidermidis, which is found on the skin of most people. It is a commensal, associating with the host without apparent effect. Interestingly, it does generate an immune response. The bacteria bind tightly to the skin; part of one big protein seems to get exposed to the immune system. What the scientists did here was to engineer a vaccine target into that protein. It worked; mice with the modified bacteria on their skin generated an immune response to the target, and were protected against a disease challenge.

Questions remain, but it seems promising.

* News story: Stanford scientists transform ubiquitous skin bacterium into a topical vaccine share -- Stanford University scientists' findings in mice could translate into a radical, needle-free vaccination approach that would also eliminate reactions including fever, swelling and pain. (Bruce Goldman, Stanford University, December 11, 2024.)
* The article: Discovery and engineering of the antibody response to a prominent skin commensal. (Djenet Bousbaine et al, Nature 638:1054, February 27, 2025.)

More Staph... Can the Staph solve the Staph problem? (July 12, 2010). Links to more.

This post is listed on my page Biotechnology in the News (BITN) -- Other topics under Vaccines (general).

Berkelocene - and the first Bk-C bond

April 2, 2025

Scientists from Berkeley have reported synthesis of the first organic compound containing the element berkelium. That is, they report the first known Bk-C bonds.

One molecule of berkelocene. It consists of one atom of Bk "sandwiched" between two planar and (partially) aromatic ring systems.

This is trimmed from Figure 1 of the article.

Berkelocene is the latest in a family of metallocene compounds that was recognized when the nature of ferrocene was worked out in the 1950s. The current work is quite a technical feat, given that the supply of Bk on Earth is (presumably) zero. The work depended on making the element in-house, and used about a half milligram of Bk over the course of the project. Experimental and theoretical analyses combined to give a picture of how the Bk interacts with the ring system. The work suggests that the Bk is present as a species very near Bk⁴⁺.

* News story: Scientists Discover New Heavy-Metal Molecule 'Berkelocene'. (Theresa Duque, Lawrence Berkeley National Laboratory, March 11, 2025.) From the lead institution, in the hills just above the UC Berkeley campus. Many scientists, including some of the current authors, have dual appointments in the National Lab and the University.
* The article: Berkelium-carbon bonding in a tetravalent berkelocene. (Dominic R Russo et al, Science 387:974, February 28, 2025.)

* More berkelium: Chemical element #117 (April 13, 2010).
* This post is listed on my page Introductory Chemistry Internet resources in the section Lanthanoids and actinoids.

March 2025

How ticks stick

March 26, 2025

Tenacious, aren't they? It almost seems that ticks glue themselves to your skin. In fact, that is exactly what they do.

The general point that ticks produce a glue in their saliva has been known for a while. A new article explores how it works. The scientists were studying proteins rich in the amino acid glycine. Proteins with a high content of this small amino acid tend to be disordered, and their fate can depend on the conditions. Turns out that the tick-glue protein is of this type. And it tends to separate into a gel-like structure. Upon evaporation of the water, it becomes quite strong.

To protein chemists, this is a story of intrinsically disordered proteins (IDP), a type of protein not well accepted until recently. (After all, we have been brought up with structure being a key feature of proteins.) Further, it is a story of phase transitions, which are increasingly recognized as a normal part of biology. Interesting, and possibly useful... Understanding tick glue might, someday, allow development of anti-tick agents. Or, it might be useful in designing adhesives for bio-medical use.

* News stories:
- Protein cement is the trick to how ticks stick. (James Urquhart, Chemistry World, January 10, 2025.)
- Behind the Paper: How ticks stick: on the phase separation and ageing of glycine-rich protein from tick adhesive -- Ticks are blood-feeding parasites that produce a strong bioadhesive using their saliva, allowing them to firmly attach to the host. We show that a disordered glycine-rich protein from tick saliva undergoes liquid-liquid phase separation, exhibits liquid-to-gel transition, and has adhesive property. (Siddharth Deshpande, Nature Research Communities, November 29, 2024.) From one of the senior authors of the article. It is a nice story about collaborative science.
* The article (open access): Phase separation and ageing of glycine-rich protein from tick adhesive. (Ketan A Ganar et al, Nature Chemistry 17:186, February 2025.)

A recent post about ticks... Can ticks transmit CWD prions? (May 28, 2023).

Among posts about other sticky animals... Watching barnacles move (October 19, 2021).

A post about possible phase transitions in biopolymers -- in this case, RNA... Triplet-repeats: Do they act through the RNA? (September 24, 2017).

Nanopasta

March 19, 2025

Pasta, at its most basic, is made from a mixture of flour and water, which is then shaped as desired. For spaghetti, it is extruded through small holes, leading to strands about one millimeter in diameter. Scientists now report doing something similar, but pulling the strands through a needle tip with the aid of an electric current. That is, this is an electrospinning process. The result is a spaghetti-like material about a thousand times thinner. Their measurements show an average strand thickness of about 400 nanometers.

How does it taste? They don't know (I think). They aren't trying to make food; they are exploring novel materials. For example, they think the nanopasta could be useful for bandages. Good protection against bacteria, coupled with good gas exchange. Using ordinary white flour provides a readily available and inexpensive starting material.

* News story: The World's Thinnest Pasta Is Here - But It's Not for Eating. Nanopasta might not make it to your dinner plate, but its ultrathin structure could revolutionize wound care. (Mihai Andrei, ZME Science, November 22, 2024.)
* The article (open access): Nanopasta: electrospinning nanofibers of white flour. (Beatrice Britton et al, Nanoscale Advances 6:6129, December 21, 2024.)

Previous pasta post: Briefly noted... Pasta that is stronger than steel (January 16, 2019).

Will a bonobo help a person find hidden food?

March 12, 2025

Maybe. Depends on what the bonobo knows about the person. If they know the person already knows where the food is, then there is no need to help. Controlled testing suggests that is how it works. The bonobo tends to help a person find the food -- unless they know the person already knows. (The bonobo saw the person watching -- or not -- as the food was hidden.)

That is, the bonobo adjusts its behavior depending on their understanding of the person's mind. That's what is called theory of mind. People have a theory of mind; they know what others are thinking, and adjust their behavior to match. Whether other animals, including the great apes, have a theory of mind has been a contentious point, with evidence on both sides. An earlier post introduced the issue, with note of the debate. The current work is from the same scientist, and includes more extensive testing with more complete controls. Whatever one thinks of the details of the current work, it is another example of an attempt to address the question with controlled tests.

* News story: Experimental results show that bonobos can sense what humans don't know and give them hints. (GIGAZINE, February 4, 2025.) Includes links to two other news stories, both good.
* The article (open access): Bonobos point more for ignorant than knowledgeable social partners. (Luke A Townrow & Christopher Krupenye, PNAS 122:e2412450122, February 3, 2025.)

Background post: Do apes have a "theory of mind"? (February 19, 2017). The article of this earlier post is reference 3 of the current article. The lead author of the earlier work is the senior author of the current article.

Special note... Three days before my planned posting of this item I was doing a routine check of the Calendar of Events at UC Berkeley, looking for seminars that might be of interest over the coming week. There he was: Christopher Krupenye, an author of both this and the earlier article; the distinctive name caught my eye. Psychology Department seminar the next day: "The Social Minds of Humans and Other Apes". So I went. Good talk, with broad discussion of the context, as well as presentation of some results, including some from the current work. If you get a chance to hear him, highly recommended.

Would NbP be better than Cu?

March 5, 2025

Better for what? For making electrical wires. A new article suggests that it might -- under certain special conditions. The scientists show that as one makes thinner and thinner layers, the electrical conductivity of niobium phosphide increases. (They use thin layers rather than wires as a model system.) In contrast, the conductivity of copper decreases in thin layers. For layers thinner than about 5 nanometers, the conductivity of NbP is better than that of Cu. Thus NbP might be better for nano-electronics. More efficient -- and that also means less heat.

Do they understand why this happens? They have some ideas. The key point is that the behavior of surfaces plays a bigger role as the layers become thinner. And it seems that the electrical properties of the surfaces are quite different for the two cases.

An intriguing finding.

* News stories:
- Meet the Ultrathin Conductor Set to Replace Copper in Advanced Electronics. (SciTechDaily (Stanford University), January 12, 2025.)
- Revolutionizing Nanoelectronics: A Breakthrough in Ultrathin Conductors. (Bioengineer.org, January 8, 2025.)
* The article: Surface conduction and reduced electrical resistivity in ultrathin noncrystalline NbP semimetal. (Asir Intisar Khan et al, Science 387:62, January 3, 2025.)

More niobium: Air pollution: progress towards a process for ammonia oxidation (April 5, 2019).

February 2025

Obelisks: a new life-form, in your mouth?

February 26, 2025

A new life-form? That sounds exciting. Or maybe suspicious. A recent article reports some interesting observations, and interprets them in terms of a new life-form. The observations are indeed intriguing; how they should be interpreted can remain open for now.

So what are the observations? Small pieces of circular RNA. These RNAs fold into rod-shaped structures, which the scientists call obelisks. Sequencing of obelisk RNAs shows that they form a distinct and novel cluster -- and that they may code for a couple of small proteins (one of which they call oblin). (In contrast, viroids code for no proteins.) And they are widespread. The authors claim to have "identified 29,959 distinct obelisks" (from the abstract). About half of all people tested have them in their mouth.

What do these things do? In one case, the scientists found a strain of bacteria that was associated with a specific obelisk. They were able to isolate bacteria free of obelisks. There was no apparent effect. Beyond that, they have no idea what obelisks do.

For now, we can only suggest that the current article is the first in the new biological field of obeliskology.

* News story: A new virus-like entity has just been discovered - 'obelisks' explained. (Ed Feil, The Conversation, February 5, 2024.) Links to news stories in major journals.
* The article: Viroid-like colonists of human microbiomes. (Ivan N Zheludev et al, Cell 187:6521, November 14, 2024.)

The Wikipedia page on Viroid provides some perspective on various things smaller than viruses. It briefly mentions the new finding of obelisks.

And of course, there is Wikipedia: Obelisk (biology). Presumably, this page will be updated with new developments as they occur.

Previous Musings posts containing (any form of) the words obelisk or viroid: none.

This post is listed on my page Unusual microbes.

A ring for Earth?

February 19, 2025

The rings of Saturn are prominent, almost a defining feature of that planet. As we got better observations, we found rings around other bodies. Even little Chariklo seems to have rings; see background post below. How about us? We don't see Earth rings, even with telescopes. But a new article suggests that Earth might have had a ring (or ring system) 460 million years ago -- one big enough to have major consequences for Earth climate.

What leads to the suggestion that Earth had a ring? There is a cluster of meteor craters from about the same time in about the same place. The authors suggest that one could account for this if an asteroid approached the Earth and broke up, forming a debris ring. Over the next few (million) years, the debris settled to Earth, giving us a set of craters in a relatively small region of time and space. Further, there was an ice age at about the same time; the authors suggest that the dense debris ring acted as a sunscreen, leading to the ice age.

Direct evidence for a ring? Not really. It's a hypothesis to explain some Earth features that we do see. It is supported by computer modeling, at this point.

* News stories:
- Earth Might Have Had a Ring System Like Saturn Millions of Years Ago -- The ring might have acted like a giant sunshade, causing a cooling effect that might have unleashed an ice age. (Tibi Puiu, ZME Science, December 31, 2024.)
- Hidden craters reveal Earth may once have had a ring - like Saturn. (Andrew Tomkins, The Conversation, September 15, 2024.) From the lead author of the article.
* The article (open access): Evidence suggesting that earth had a ring in the Ordovician. (Andrew G Tomkins et al, Earth and Planetary Science Letters 646:118991, November 15, 2024.)

Background post about rings: Rings for Chariklo (May 9, 2014). Links to more.

A novel and simple way to make ammonia?

February 12, 2025

2 N₂ + 6 H₂O --> 4 NH₃ + 3 O₂.

Both reactants are in the air. Just get them to react.

A new article reports that it works rather well -- and that includes a small test of a prototype device in the field. Developing a catalyst was the heart of the work. The scientists end up using a mixture of iron oxide and an acidic polymer called Naflon. The process uses chemicals from the air, and produces a dilute solution of ammonia, suitable for direct application to crops. No external energy is needed, and there is no greenhouse gas emission.

That is all in contrast to the well-established Haber-Bosch process for making ammonia. The new process offers the possibility of inexpensive and sustainable ammonia, produced on-site as needed. The process works, but does need further development, to scale it up to become practical for large fields.

* News stories:
- This New Catalyst Can Produce Ammonia from Air and Water at Room Temperature -- Forget giant factories! A new portable device could allow farmers to produce ammonia right in the field, reducing costs, and emissions.. (Mihai Andrei, ZME Science, December 17, 2024.) (The final sentence, leading to the article, gives the wrong journal name, but the link is correct.)
- New device produces critical fertilizer ingredient from thin air, cutting carbon emissions. (Rob Jordan, Stanford University, December 13, 2024.) From the lead institution.
* The article (open access): Onsite ammonia synthesis from water vapor and nitrogen in the air. (Xiaowei Song et al, Science Advances 10:eads4443, December 13, 2024.)

More about making ammonia: A better way to make ammonia, using lithium? (July 19, 2021).

A mutation that may lead to "bird flu" virus being better able to infect humans

February 5, 2025

Scientists have introduced a single specific mutation into the HA (hemagglutinin) gene from a new isolate of H5N1 bird flu virus, and shown that it makes the viral HA protein bind better to the human flu virus receptor. The specific mutation had previously been associated with improved binding to the human receptor; the current work extends that to the background of an H5N1 isolate from cattle. This is lab work, using purified proteins. It is not clear how the finding would carry over to the complexity of the real world. But it does illustrate how the virus might change its host specificity, and in some general sense is a concern.

* News stories:
- Scripps Research scientists identify mutation that could facilitate H5N1 "bird flu" virus infection and potential transmission in humans -- New findings underscore the importance of ongoing surveillance for H5N1 mutations that pose risks to public health. (Scripps Research Institute, December 5, 2024.) From the lead institution. Useful overview.
- Bovine H5N1 influenza shows potential for human adaptation through key mutations. (Vijay Kumar Malesu, News-Medical.net, December 9, 2024.) Includes more detail about the work.
- Expert reaction to study of single mutation in bovine influenza H5N1 hemagglutinin and specificity to human receptors. (Science Media Centre, December 5, 2024.) Multiple views from flu exports.
* The article: A single mutation in bovine influenza H5N1 hemagglutinin switches specificity to human receptors. (Ting-Hui Lin et al, Science 386:1128, December 6, 2024.)

Posts on flu are listed on the supplementary page Musings: Influenza.

January 2025

On reducing meat consumption: The squirrels dissent

January 30, 2025

What do squirrels eat? Acorns and such. In fact, it has long been known that squirrels do consume some meat, though the role of meat in their diet is unclear but generally minimal. For example, do they actually attack animals, or merely scavenge what they may find? A new article is part of a multi-year study of squirrels in a park area. One summer, the squirrels were seen to regularly hunt and attack voles (small rodents) and eat them. The scientists were surprised, but they have many videos. The vole-eating was seen at a peak in the vole population. The observations raise questions about what controls the behavior, but at least it shows more flexibility in squirrel diet than previously recognized.

The sources listed below contain or link to photos and videos of squirrels eating voles.

* News story: UC Davis study finds never-before-seen carnivorous squirrels. (Kat Kerlin, UC Davis, December 19, 2024.)
* The article, which is open access: Vole hunting: novel predatory and carnivorous behavior by California ground squirrels. (Jennifer E Smith et al, Journal of Ethology 43:3, January 2025.)

For more about meat, see the previous post, just below: On reducing meat consumption: Evaluation of alternatives (January 28, 2025).

More squirrels: Super Squirrel (September 19, 2009).

On reducing meat consumption: Evaluation of alternatives

January 28, 2025

There are various reasons to promote reducing meat consumption. That leads to, what are the alternatives and what are their merits? Musings has discussed some aspects of cultured meat (growing cells from meat animals in culture). This is an interesting development, but it has significant challenges. Other alternatives include a range of plant products, with varying degrees of processing. A new article provides an extensive analysis of the issues. The author comes out with a clear winner. But a big caution... This is still a work in progress. For now, understanding the questions is as important as anything.

* News story: The best and worst meat replacements for your health, your wallet and the planet - new research. (Marco Springmann, The Conversation, December 3, 2024.) From the author of the article. Useful overview.
* The article, which is open access: A multicriteria analysis of meat and milk alternatives from nutritional, health, environmental, and cost perspectives. (Marco Springmann, PNAS 121:e2319010121, December 2, 2024.)

Among Musings posts on the topic... Tuning the protein and fat content of cultured meat (February 2, 2021).

Added January 30, 2025. Also see the next post, immediately above: On reducing meat consumption: The squirrels dissent (January 30, 2025).

Why are twin births uncommon in humans?

January 22, 2025

Twin births occur about 2% of the time in humans. In fact, they are uncommon in most primates -- but not all. A recent article explores the history behind that. The article analyzes data for litter size in nearly a thousand types of mammals, including 155 primate species. Litter size is mapped onto a phylogenetic tree. The results suggest that having twins was the ancestral state of primates. That trait has since been lost in most primate branches. The article includes extensive discussion of the merits of one litter size or another; that discussion may make the article worth reading, without getting too bogged down in the data.

* News stories:
- The Evolutionary Shift in Primate Reproduction -- From Twins to Singleton Births: The Story of Ancient Primates. (Kambiz Kamrani, primatology.net, December 17, 2024.)
- Twins were the norm for our ancient primate ancestors - one baby at a time had evolutionary advantages. (Tesla A Monson & Jack H McBride, The Conversation, December 16, 2024.) From the authors of the article -- one of whom is the mother of twins.
* The article, which is open access: The Evolution of Primate Litter Size. (Jack H McBride & Tesla A Monson, Humans 4:223, September 2024.)

For more about twins... Twins (April 30, 2009). Links to more.

Recent craters in Siberia due to methane release from hydrates in the permafrost

January 15, 2025

Methane hydrate is a complex of methane and water. It is an ice-like solid at conditions where methane itself would be a gas. There is a lot of methane underground in cold regions, where the methane hydrate is effectively part of the permafrost. There is a concern that warming of the permafrost could lead to release of the methane, which is a potent greenhouse gas and also flammable.

Concern that it might happen is being replaced by study of how it happened.

A crater on the Yamal Peninsula in Siberia.

The crater core is about 30 meters across.

This crater was first noticed in 2014. There are now about 20 such craters in Siberia, all new since about that time and many in the same region. From the time of the initial observations, it seemed likely that the craters were due to methane release, probably stimulated by climate change, but the details have been debated.

This is trimmed and reduced from the top figure on the Wikipedia page listed below; credit is given there to the scientists who provided it. There are other views of such craters in Figure 1 of the article and in the news stories.

So, what happens? The simplest model might be that the hydrate warms, releasing methane, which escapes. That model does not necessarily lead to a crater. A more complex model might postulate that the methane builds up inside a closed region, until the pressure is high enough to break it open -- explosively. A new article offers support for an even more complex process. It involves the migration and mixing of water layers of different salinities (salt content) and temperatures. That flow of differing liquid phases promotes heat transfer, and puts physical stress on the subsurface structures. The article is based largely on mathematical modeling, with some lab work that supports the idea. The model depends on the geological details of the area. Thus it helps to explain the limited geographical distribution as well as the nature of the craters.

Of course, it is reasonable that there are various processes that can lead to methane release. The current work is just an example of one way it might happen. The work serves to remind us of the likely importance of methane hydrates.

* News stories:
- Massive exploding methane craters are tearing Siberia apart and scientists finally know why -- Scientists uncover the mechanics behind Siberia's explosive craters as warming drives methane release. (Tibi Puiu, ZME Science, November 11, 2024.)
- New explanation for Siberia's permafrost craters -- The region's unique geology, not only warming and permafrost thaw, caused the methane explosions. (AGU, September 26, 2024.)
* Wikipedia page referred to above as source for the figure: Gas emission crater. (Wikipedia.) Useful overview. The current article is noted there. It is now reference #11; search the page for the lead author (Morgado) if needed.
* The article, which is open access: Osmosis Drives Explosions and Methane Release in Siberian Permafrost. (Ana M O Morgado et al, Geophysical Research Letters 51:e2024GL108987, September 26, 2024.)

Among posts about methane and its hydrate:
* Methane hydrate: a model for pingo eruption (August 4, 2017).
* Climate change: Should we focus on methane? (March 24, 2012).
* Ice on fire (August 28, 2009).

Photosynthetic hamster cells

January 8, 2025

Scientists have added chloroplasts to hamster cells growing in lab culture. The chloroplasts functioned for at least two days; there is at least a hint that they contributed fuel to the cell economy. This appears to be the first example of free chloroplasts (that is, not within their own host cell) functioning in animal cells. What will it take to get good chloroplast function over an extended period? We'll see.

The authors suggest an interesting lab use for such photosynthetic animal cells. In tissue culture, they could be a useful source of oxygen for the cells.

* News story: Solar-powered animal cells. (University of Tokyo, October 31, 2024.) (The first sentence contains an "error", which I suspect is a translation error. The overall quality of the story is good.)
* The article, which is open access: Incorporation of photosynthetically active algal chloroplasts in cultured mammalian cells towards photosynthesis in animals. (Ryota Aoki et al, Proceedings of the Japan Academy, Series B, Physical and Biological Sciences 100:524, October 31, 2024.)

The current work is about the possibility of having chloroplasts within animal cells. We have previously noted examples of what might be considered photosynthetic animals. These most commonly involve associations of the animal with a photosynthetic microbe. For example... Croatian Tethya beam light to their partners (December 16, 2008). Links to more.

Posts on various aspects of endosymbiosis are listed at: Origin of eukaryotic cells: a new hypothesis (February 24, 2015).

Happy 45²

January 6, 2025

A once in a lifetime event for most of us. But it is extra special for anyone who was around in 1936.

This post is listed on my page Internet resources: Miscellaneous in the section Mathematics; statistics.

Older items are on the archive pages, starting with 2024.

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