La bimodalità chimica della Via Lattea
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La bimodalità chimica della Via Lattea
https://www.media.inaf.it/2025/12/12/bimodalita-chimica-via-lattea/
> Un nuovo studio getta luce sulla storia chimica della nostra galassia, cercando di spiegare l’origine della sua bimodalità, ossia la presenza di due gruppi distinti di stelle con composizioni chimiche differenti. I risultati suggeriscono
Gli ultimi otto messaggi ricevuti dalla Federazione
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@swelljoe It is nearly Christmas.
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Bill Clinton should be in the same boat as Bill Cosby.
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Centolettori (ebook)
@libri - Peccato per la scarsità di notizie di contorno
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This week I bought another guitar and another domain name. Truly spiraling.
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Super-Sizing Insects and the Benefits of Bones
One swol mealworm amidst its weaker brethren. (Credit: The Thought Emporium, YouTube)
Have you ever found yourself looking at the insects of the Paleozoic era, including the dragonfly Meganeuropsis permiana with its 71 cm wingspan and wondered what it would be like to have one as a pet? If so, you’re in luck because the mad lads over at [The Thought Emporium] have done a lot of the legwork already to grow your own raven-sized moths and more. As it turns out, all it takes is hijacking the chemical signals that control the development phases, to grow positively humongous mealworms and friends.The growth process of the juveniles, such as mealworms – the larval form of the yellow mealworm beetle – goes through a number of molting stages (instars), with the insect juvenile hormone levels staying high until it is time for the final molt and transformation into a pupa from which the adult form emerges. The pyriproxyfen insecticide is a juvenile hormone analog that prevents this event. Although at high doses larvae perish, the video demonstrates that lower doses work to merely inhibit the final molt.
Hormone levels in an insect across its larval and pupa stages.
That proof-of-concept is nice of course if you really want to grow larger grubs, but doesn’t ultimately really affect the final form as they simply go through the same number of instars. Changing this requires another hormone/insecticide, called ecdysone, which regulates the number of instars before the final molt and pupal stage.Amusingly, this hormone is expressed by plants to mess with larvae as they predate on their tissues, with spinach expressing a very significant amount of this phyto-ecdysone. For humans this incidentally interacts with the estrogen receptor beta, which helps with building muscle. Ergo bodybuilding supplies provide a ready to use source of this hormone as ‘beta ecdysterone’ to make swol insects with.
Unfortunately, this hormone turned out to be very tricky to apply, as adding it to their feed like with pyriproxyfen merely resulted in the test subjects losing weight or outright dying. For the next step it would seem that a more controlled exposure method is needed, which may or may not involve some DNA editing. Clearly creating Mothra is a lot harder than just blasting a hapless insect with some random ionizing radiation or toxic chemicals.
Gauromydas heros, the largest true fly alive today. (Credit: Biologoandre)
A common myth with insect size is that the only reason why they got so big during the Paleozoic was due to the high CO2 content in the atmosphere. This is in fact completely untrue. There is nothing in insect physiology that prevents them from growing much larger, as they even have primitive lungs, as well as a respiratory and circulatory system to support this additional growth. Consequently, even today we got some pretty large insects for this reason, including some humongous flies, like the 7 cm long and 10 cm wingspan Gauromydas heros.The real reasons appears to be the curse of exoskeletons, which require constant stressful molting and periods of complete vulnerability. In comparison, us endoskeleton-equipped animals have bones that grow along with the muscles and other tissues around them, which ultimately seems to be just the better strategy if you want to grow big. Evolutionary speaking this makes it more attractive for insects and other critters with exoskeletons to stay small and fly under the proverbial radar.
The positive upshot of this is of course that this means that we can totally have dog-sized moths as pets, which surely is what the goal of the upcoming video will be.
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Good move, Amtrak! Come on, corporations—do the right thing here; it’s actually good for business too!
Amtrak is slashing executive bonuses to give out $900 apiece to over 18,000 rank-and-file workers
https://fortune.com/2025/12/12/amtrak-bonuses-for-18000-workers-900-apiece/
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