If you’re both a LEGO and a Dune fan, unless you’ve been living in a cave on Mars with your eyes shut and fingers in your ears, you’re probably aware that LEGO released a set for the royal Atreides ornithopter. The blades flap and everything. Anyway, it comes with several minifigures, including one that doesn’t quite fit with the others — a full-length Baron Harkonnen.

Given that, [gorkyver] decided to create a throne for the Baron that he could rise from, just like in the movie, while delivering the iconic line. With no reference materials available other than pausing the movie, [gorkyver] created a throne from scratch in BrickLink Studio, which made it easy to generate both a parts list and step-by-step instructions.

At the heart of this build is an Arduino Nano, which takes input from the momentary push button and starts the show. The Baron slowly rises on a rack and spur gear connected to a stepper motor, and a DF Player Mini runs the audio through a 75 mm speaker.

Rather than just buying a big box store display case off of eBay, [gorkyver] recreated the skeleton in Fusion 360 and used a hairdryer to bend a sheet of PET-G around to enclose it. A couple of sweet adhesive graphics later, and it totally looks like a real set on display. Don’t miss the demo/build video after the break.

Did you hear? The European Space Agency printed some bricks out of meteorite dust, and there might be one on display near you.

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If you’ve ever watched Predator, you’ve noted the tactical advantage granted to the alien warrior by its heat vision. Indeed, even with otherwise solid camoflauge, Dutch and his squad ended up very much the hunted.

And yet, back in reality, it seems the prey might be the one with the ability to sense in the infrared spectrum. Research has now revealed this unique ability may all be down to the hairs on the back of some of the smallest mammals.

Not By The Hair Of My Backy-Back-Back

Some marsupials and mammals seem to share similar “guard hair” structures, though they diverged evolutionarily as far back as the Jurassic period. Credit: research paper
Small mammals, like shrews and rodents, have fur that combines multiple types of hair into a thick protective coat. The fur must keep the animal warm, relatively dry, and protect it from the elements. But what if it could also protect against predators? For amongst this fur lie special “guard hairs” which researchers now believe act as finely tuned infrared sensors.

Guard hairs only make up maybe 1-3% of the fur. They usually stick out straight, protruding to a degree from the rest of the coat. They also tend to feature a rather distinctive banding pattern not seen on other types of mammalian hair.

For years, the periodic banding patterns observed in the guard hairs of small mammals puzzled scientists. These hairs exhibit internal bands spaced at intervals of 6-12 micrometers. If you’ve recently been staring at a chart of the electromagnetic spectrum, you might realize closely aligning with the wavelengths of infrared radiation. This hinted at an unrecognized function—an ability to sense infrared light, perhaps. Indeed, those wavelengths cover the same part of the infrared spectrum used by heat-seeking missiles and thermal imaging devices.

This was a feature with clear survival benefits for nocturnal and heavily predated animals. It could give a small creature the ability to detect warm heat sources—like a predator—approaching from behind. No need to have eyes on the back of one’s head, nor be forever looking over one’s shoulder. If your thermal sense picks up something warm approaching from behind, it might be worth making a dash action.

Researchers focused their guard hair research on three species: Mus musculus, the house mouse, Antechinus agilis, a mouse-like marsupial, and Sorex araneus, the common shrew. Despite the many differences amongst the species, the guard hairs share some similarities. Their findings showed that despite evolutionary divergences that stretch back millions upon millions of years, these species share highly similar microscopic hair structures that appear to be tuned to wavelengths between 8-12 um—perfect for thermal imaging.
The structure of a guard hair from the house mouse, Mus musculus. Similar guard hairs are found on other rodents. Credit: research paper
Taking the house mouse as the main example, the hairs have a sophisticated structure. The wider sections of guard hairs, referred to as the the “shield,” are believed to act as infrared absorbers. They have a effectively two tubes joined by a membrane, with air cavities spaced at periodic intervals of approximately 10 um. Towards the base of the shield area, the hair narrows, and instead of air cavities, the hair features the characteristic dark bands with similar spacing. It’s believed the narrower sections help focus absorbed infrared energy into the base of the hair. A relatively variable “zipper” section then follows, with dark hemispheres arranged around the axis of the hair. This is believed to act as a “spectral filter” that radiates away wavelengths outside the 8-12 um band. Calculations suggest that the zipper filter means that infrared energy in that critical wavelength range makes up 72% of the “signal” reaching the base of the hair, rather than just 33% otherwise. The final section of the shaft has finer banding, at a spacing of just 6 um.
The structure of the hairs is likened to the structure of a Fiber Bragg Grating (FBG). Credit: Sakurambo, CC BY-SA 3.0
It’s believed that hairs act akin to infrared antennas—with their stiff, straight alignment and periodic banding enabling them to act as thermal detectors. The bands themselves appear to be made of infrared-transparent biological material of varying refractive indexes. Researchers liken this to a man-made invention called a fiber Bragg grating, or FBG. This device uses periodic variation in refractive index of an optical fiber to create a filter for a particular wavelength. Guard hairs could use a biological version of the same mechanism to filter out the infrared wavelength of interest.
The “zipper” section of the hair is believed to act like a spectral filter, radiating out wavelengths that aren’t of interest. Credit: research paper
Meanwhile, to pick up the signal, the animal would need some kind of sensor cell at the base of the hair. Indeed, researchers found that the house mouse does indeed have Merkel cells uniquely located at the base of guard hairs, arranged around the shaft. It’s believed these cells may be responsible for the actual infrared sense, with the hairs themselves just acting as antennas to focus the infrared energy to them.

The researchers also branched out, looking at whether predators may have adapted around this in turn. Notably, they found that cold-blooded snakes were virtually invisible in the thermal infrared range. Similarly, cats are relatively low in thermal emissions from the forward aspect. Both would thus have an advantage at hunting against mammals with a thermal sensing defence mechanism. And indeed, these creatures are particularly adept at hunting mice and other small mammals, as you’d expect!
Guard hairs appear to have different sensory connections compared to other hair types in given mammals. Credit: research paper
The research is still at an early stage. Further work remains to confirm the true purpose of these guard hairs. Regardless, their complex microstructures do provide compelling evidence that they are indeed acting as antennas to capture infrared radiation for sensory purposes.

The discovery of these natural infrared sensors is not just a biological curiosity. It could also serve useful in the field of photonics. The guard hairs’ ability to act as finely tuned infrared antennas could potentially act as inspiration for new optical devices, or to improve on current technologies.
The marsupial Antechinus agilis has a similar structure in the shield area of the guard hair, though differs towards the base. It’s thought it uses the diamond cuticle section to pass infrared radiation around 10 um wavelength, while radiating other wavelengths away. Credit: research paper
Additionally, this research could influence evolutionary biology, providing new insights into the ancient origins of mammalian and marsupial hair. Guard hairs’ resilience over millions of years suggests they played a crucial role in early mammalian survival, possibly dating back to the Triassic period.

In any case, certain tiny mammals have always been wildly capable at evading predators that sneak up from behind. We might now have a secret insight into this little party trick. Perhaps it was never their eyes, or a keen sense of vibration, but a hidden thermal sense that was lurking in the fur all along.

Featured image: “Lab mouse mg 3263” by [Rama]

Tensions between Meta and the EU intensified on Monday (22 July), with the European Commission and European consumer authorities saying the US tech giant may be breaching consumer protection law with its “pay or OK” model.

euractiv.com/section/platforms…

[M Caldeira] had a project in mind: replacing a common vacuum tube with a solid-state equivalent. The tube in question was an EABC80 or 6AK8 triple diode triode. The key was identifying a high-voltage FET and building it, along with some other components, into a tube base to make a plug-in replacement for the tube. You can see a video about the project below.

These tubes are often used as a detector and preamplifier. Removing the detector tube from a working radio, of course, kills the audio. Replacing the tube with a single diode restores the operation of the radio, although at a disadvantage.

From there, he adds more diodes directly into the socket. Of course, diodes don’t amplify, so he had to break out a LND150 MOSFET with a limit of 500 volts across the device. It takes some additional components, and the whole thing fits in a tube base ready for the socket.

Usually, we see people go the other way using tubes instead of transistors in, say, a computer. If you want real hacking, why not make your own tubes?

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Su basta!, un media indipendente francese, c’è un interessante articolo che presenta l’esperienza delle “banche del tempo libero“ (Fritidsbanken), in particolare la sede di Malmoe, nel sud della Svezia: basta.media/Suede-recycleries-…

La sede si trova in un centro commerciale eha l’aspetto di un normale negozio di articoli sportivi, ma lì sci, pattini in linea, racchette da tennis, palloni, tende e altri articoli sportivi sono di seconda mano e non si vendono, ma si prestano gratuitamente per due settimane, basta lasciare il proprio nome e il proprio numero di telefono.
Nella sede di Malmoe c’è spazio anche per accese partite ai due tavoli da ping pong e non mancano le attività per la riparazione delle attrezzature, secondo la responsabile al momento nel negozio si prestano circa 150 oggetti al giorno, d’inverno, il doppio.

L’associazione delle Fritidsbanken è nata nel 2013 ed ora è diffusa in molti centri del paese, ha come scopo dare nuova vita ad attrezzature sportive usate, prestandole gratuitamente per promuovere l'attività sportiva e all'aria aperta. Le “banche del tempo libero” vengono finanziate dalle amministrazioni locali da associazioni per la promozione dello sport, da fondazioni e da alcune regioni.

L’associazione ha un suo sito con una versione anche in inglese dove spiega che cosa sono e come funzionano le Fritidsbanken: fritidsbanken.se/en/how-it-wor…

Un grand merci, un grosso grazie a @Basta! per la segnalazione di questa bella iniziativa.
#EconomiaCircolare #biblioteche #Svezia #sport #ambiente #condivisione #BancheDelTempoLibero @macfranc