2026-03-11 01:00:56
Alzheimer’s disease remains a frustratingly difficult condition to manage for the millions of patients affected worldwide and their families. The cause of the disease is still not properly understood, and by the time memory loss and cognitive decline become apparent, the underlying brain pathology has often been quietly building for decades.
Soon, though it may be possible to diagnose impending Alzheimer’s disease ahead of time, before symptoms have taken hold. New research suggests this could be achieved through a simple blood draw, providing clinicians and patients precious time to manage the condition and plan ahead.
A hallmark of Alzheimer’s disease is the buildup of amyloid and tau protein in the brain. Despite decades of research, the protein’s precise role in the disease remains somewhat unclear. Typically, Alzheimer’s disease is diagnosed by symptoms like memory loss and cognitive decline, with later investigation revealing the presence of elevated levels of these proteins in the brain. This investigation often involves brain imaging or invasive and painful spinal fluid tests.
However, researchers have developed a new predictive model that suggests it’s possible to estimate when a person will begin showing Alzheimer’s symptoms, based on a similar marker. The key ingredient is another protein called p-tau217, which circulates in the blood plasma and mirrors the slow, steady accumulation of amyloid and tau protein within the brain tissues.
Earlier research had previously established that p-tau217 levels tended to track alongside the rise of amyloid and tau buildup in the brain. This indicated that the level of p-tau217 in the blood could be a proxy for how far along the disease process has progressed. This allows the estimation of how many years remain before symptoms emerge for a given patient, with the research study suggesting this could be as specific as a margin of three or four years.
The research study drew on data from 603 older adults enrolled in two long-running studies — the Knight Alzheimer Disease Research Center at WashU Medicine and the multi-site Alzheimer’s Disease Neuroimaging Initiative. Plasma p-tau217 was measured using simple blood draws. One of the more interesting findings concerns age. The model revealed that the interval between elevated p-tau217 levels and symptom onset isn’t fixed. A person whose levels first ticked upwards at the age 60 might not develop noticeable cognitive problems for another two decades. But if that same elevation appeared at age 80, symptoms tended to follow within about eleven years. It suggests that younger brains appear to tolerate Alzheimer’s-related pathology for longer, while older brains are less able to withstand the protein buildup once the process gets underway.
Right now, p-tau217 testing is primarily used to help confirm an Alzheimer’s diagnosis in patients who are already experiencing cognitive trouble. It isn’t recommended for screening asymptomatic individuals outside of research settings. However, using p-tau217 as a predictive marker has obvious potential. If clinical trials for preventive Alzheimer’s drugs could enroll participants based on a predicted timeline for symptom onset, rather than waiting years for decline to actually happen, those trials could become dramatically shorter and cheaper to run, and more efficient in general. Perhaps more importantly, it has the potential to give patients a better understanding of what lies ahead, allowing them to plan ahead before cognitive symptoms become an unmanageable imposition on their life.
The research team has made their model development code publicly available on Github and created a web-based tool that lets other researchers explore the clock models in detail. Looking ahead, they note that combining p-tau217 with other blood-based biomarkers linked to cognitive decline could sharpen predictions even further. It’s still early days, but a future where a routine blood test could serve as an early-warning system for Alzheimer’s is looking more plausible than it did a few years ago.
2026-03-10 23:30:21
Who among us does not have a plethora of mains-powered devices on their workbench, and a consequent mess of power strips to run them all? [Jeroen Brinkman] made his more controllable with a multi-way switch box.
At first sight it’s a bank of toggle switches, one for each socket. But this is far more than a wiring job, because of course there are a couple of microcontrollers involved, and each of those switches ultimately controls a relay. There are also status LEDs for each socket, and a master switch to bring them all down. Arduino code is provided, so you can build one too if you want to.
We like the idea of a handy power strip controller, and especially the master switch with the inherent state memory provided by the switches. This could find a home on a Hackaday bench, and we suspect on many others too. It’s by no means the first power strip with brains we’ve seen, but most others have been aimed at the home instead.
2026-03-10 22:00:15
After all the crashing and burning of Imperial Germany’s Zeppelins in the later part of WWI – once the Brits managed to build interceptors that could hit their lofty altitude, and figured out the trick of using incendiary rounds to set off the hydrogen lift gas – there was a certain desire in airship circles to avoid fires. In the USA, that mostly took the form of substituting hydrogen for helium. Sure, it didn’t lift quite as well, but it also didn’t explode.
Still, supplies of helium were– and are– very much limited, and at least on a rigid Zeppelin, the hydrogen wasn’t even the most flammable part. As has become widely known, thanks in large part to the Mythbusters episode about the Hindenburg disaster, the doped cotton skin in use in those days was more flammable than some firestarters you can buy these days.
That’s a problem, because, as came up in the comments of our last airship article, rigid airships beat blimps largely on Rule of Cool. Who invented the blimp? Well, arguably it was Henri Griffard with his steam-driven balloon in 1857, but not many people have ever heard his name. Who invented the rigid airship? You know his name: Ferdinand Adolf Heinrich August Graf von Zeppelin. No relation. Probably. Well, admittedly most people don’t know the full name, but Count Zeppelin is still practically a household name over a century after his death. His invention was just that much cooler.
That unavoidable draw of coolness led to the Detroit Airship Company and their amazing tin blimp. The idea was the brainchild of a man named Ralph Upton, and is startling in its simplicity: why not take the all-metal, monocoque design that was just then being so successfully applied to heavier-than-air flight, and use it to build an airship?
Of course everyone’s initial reaction to the idea is that it’s absurd: metal is too heavy to fly! They said that about airplanes once, too, but airships are surely a different matter. Airships must be lighter than air. Could a skin of aluminum really hold enough lift gas to keep itself in the air? Upton convinced no lesser lights than Henry Ford to back him, and the Detroit Aircraft Company ultimately found a customer for the design in the US Navy.
It helped that Upton wasn’t exactly the first to come up with this idea: David Schwarz had tried to build a metal airship at the end of the 19th century. Arguably it is he who invented the rigid airship, not my aura farming not-ancestor. His design had metal skin over an internal framework, rather than the lighter monocoque construction Upton was exploring. While it was by no means a success, being destroyed on its maiden flight, the fact that it had a maiden flight at all at least proved that metal structures could be made light enough to get off the ground.
The Detroit Airship Company’s first– and only, as it turned out– prototype was much more successful, as we will see. It was immediately nicknamed the “tin blimp” by the press after it was unveiled in 1929, that name was incorrect in every particular. It wasn’t tin, and it wasn’t a blimp. Well, not exactly, anyway. More on that later.
Compared to the various frames, longitudinal girders, bracing wires and fabric-backed gas bags of a Zeppelin-type airship, the ZMC-2’s balloon was simplicity itself. The balloon–if you can call it that–was a hollow spheroid built up of strips of 0.0095” (0.24 mm) Alclad sheeting. Alclad is a sort of metallic composite material: a sheet of duraluminum coated with a very thin protective layer of pure aluminum to provide corrosion resistance. The ZMC-2 was actually the first major use of Alclad, but hardly the last. At least for skins, most aircraft aluminum is actually alclad, as alloys with the desired strength-to-weight ratio are generally too vulnerable to corrosion to be exposed to the elements.
So, contrary to popular belief, no tin was involved. And the sturdy aluminum spheroid was not at all flexible, so the ZMC-2 was not really any kind of blimp. It also was not, technically, a Zeppelin. It was a whole new beast: a metalclad airship.
There is a film of the ship being built, and it’s rather fascinating. The strips of alclad are rolled into conical sections and riveted together, with a bituminous material serving as sealant. Even today, you would not want to weld this material, so instead three and a half million 0.035” (0.89 mm) rivets hold the plates together. A special automated riveting machine was invented for the construction of the metalclad airship, which “sewed” three rows simultaneously at a rate of five thousand rivets per hour.
Just like most monocoque airplanes, then and now, the skin doesn’t hold the entire load: there were five circular frames, flanged and full of lightening holes just like the ribs of an aeroplane fuselage, of various diameters to help the ‘gas bag’ hold shape. The gondola would attach to two of these.
Amazingly, with all of those rivets and the low-tech sealant, the metalclad held helium much better than its rivals. Yes, helium. While more expensive than hydrogen, the US Navy had already transitioned away from that more volatile gas and had no interest in going back. All of their groundside infrastructure was centered around helium. If that meant that the fireproof metalclad would not be able to lift quite so much as it otherwise might, well, too bad.
Aside from outward appearance, the metalclad airship is similar to a blimp in some respects. For one, like the blimps that would go on to serve into and well past WWII, and unlike every Zeppelin ever built, the metalclad design had no internal subdivisions. The great metal balloon, 52 ‘8 ” in diameter (16 m) and 149’ 5” (45.5m) long, held two air bladders, one fore, and one aft, but was otherwise cavernously empty.
Just like the blimps, those air bladders were used for trim: by pressurizing the fore bladder, the nose becomes heavy and trims the blimp down; likewise pressurizing the rear bladder trims the nose upwards. With both under pressure, the overall excess lift of the gasbag is reduced slightly, though the hull was not designed to withstand enough pressure for that to be notably useful at affecting overall buoyancy. The maximum the ZMC-2’s hull could take was said to be about two inches of water, or 0.07 PSIg (0.5 kPa).
Also like a blimp, that pressure was required to resist the force of aerodynamic drag, at least at high speeds. The aluminum skin could hold its own shape, obviously, and even at low speeds it was safe to fly at atmospheric pressure, but at speeds above about half velocity never exceed (VNE) there was a risk of buckling the nose. So, like a blimp–or the balloon tanks on the much later Atlas rockets–gas pressure was used as reinforcement. For that reason, there was much consternation at the time–and since–whether to count the metalclad as a rigid or non-rigid airship. Ultimately the US Navy, whose code was “Z” for airship and “R” for rigid or “S” for non-rigid, called it ZMC– z-airship, metal clad. That dodged the issue well enough.
A larger ship might have been able to afford the weight of stronger aluminum to take the buffeting of high-speed flight, thanks to the square-cube law, but the comparatively tiny ZMC-2 lacked that lift capacity. Even larger ships were always intended to use pressure-reinforcement; it’s a key part of the metalclad concept. Why waste lift capacity on metal when the gas can do it for you? As it was, the useful load of the prototype ZMC-2 was only 750 lbs (340 kg). The ZMC-2 wasn’t designed for useful load, though; it was only ever meant as a testbed.
As a testbed, the ZMC-2 was reasonably successful, and also a complete failure. It was reasonably successful in that its logbooks recorded 2,265 incident-free hours over 725 flights between its debut in August 1929 and its grounding in August 1939. In those ten years, it was found to fly well, in spite of its oddities.
The control car, with its crew of two or three–plus four passengers–and a pair of 220 HP Wright Whirlwind engines, would not have looked out of place on a blimp of similar size. Its overall size was not unlike blimps Goodyear was flying. Nor was the ZMC-2 particularly speedy, or unusually slow with a top speed of 70 mph (113 km/h). Aside from the metal-clad construction, two things made the ZMC-2 stand out amongst its contemporaries. The empennage — the “tail” — was perhaps unique in airship history– as near as I can tell, the Detroit Airship Company was the only one to ever fit eight equally-spaced fins to the rear of an airship. All had control surfaces, and in practice, there was no control mixing: four acted as elevators, and four as rudders. It worked well enough, as the ship was apparently quite maneuverable.
The other oddity helped with this maneuverability: the airship’s fineness ratio. It was oddly squat, at only 2.83. Like much in the world of airships, the concept of a fineness ratio is borrowed from the naval world– there, it is the ratio between a ship’s length and its beam, or width. For a flying ship, it’s the length to diameter of the gas bag, but the effect is the same. Picture a racing skiff vs a coracle, or a whitewater kayak. The racing skiff has a very high fineness ratio, which gives it high speed and low maneuverability as it cuts through the water. A coracle or whitewater kayak, on the other hand, has a low fineness ratio, often less than two, so that they can turn on a dime. They’re also incredibly difficult to keep going in a straight line. The ZMC-2 wasn’t quite that squat, but from the boating analogy I can only imagine it was a handful to keep on a straight course at times.
The only reason I dare call the fabulous tin blimp a failure is because there was no ZMC-3, or -4, or N≠2. It was indeed the only metalclad to ever fly.
It wasn’t the cute little prototype’s fault; it was the timing. The Detroit Aircraft Company launched the ZMC-2 with big plans– Upton’s first design was for a larger express passenger/cargo airship of 1,600,000 cu.ft. (45,307 m³) gas volume, compared to the meager 200,000 cu.ft. (5,663 m³) of the prototype. There was interest in the bigger designs, but the ZMC-2 would need to prove the concept– which it did, in August 1929. Then in October, the stock market crashed, the Great Depression hit, and there was a lot less money available for pie-in-the-sky ideas like metalclad airships.
The interest was there, mind you. The U.S. Army liked what they saw, and went hat-in-hand in 1931 to Congress asking for 4.5 million to buy a 20-ton-lift model that would have been larger than the Graf Zeppelin. At that point, Congress felt there were other priorities. Later on, Detroit’s metalclad design was The Navy’s preferred choice to replace the ill-fated Akron and Macon, but there were problems with funding and the Detroit Aircraft Company didn’t have a hangar big enough to build the thing in anyway.
That was the end of it. Though there was no notable metal fatigue or corrosion, the ZMC-2 flew less and less as the odds of a successor dropped. Some accounts claim it was grounded completely in 1939; others imply a handful of flights until US entry into WWII. With the war on, aluminum was in short supply and the ZMC-2 was broken up for scrap in 1941. It was simply too small for the antisubmarine duty the Navy’s blimps were being put to, and too weird to use as a training ship. Though the gondola was kept for a time as a learning aide for ground school, it was not preserved. It is likely that no physical trace of the fabulous tin blimp remains.
Ultimately, the ZMC-2 was successful in proving that a metalclad airship could fly. During the various aborted attempts at an ‘airship renaissance’, various proposals for metalclads or similarly-built composite ships have been put forth, but as with Ralph Upton’s larger designs, no capital sufficient for construction ever materialized.
In spite of my praise of the non-rigid airship’s ability to shift with the winds– going so far as to say “Blimps win” in my last article, based on the historical record, I for one would love to see a metalclad fly again. Maybe it’s just the Rule of Cool– rigids are cooler, and metalclads are cooler yet. Maybe the image of the doughty ZMC-2 buzzing about like a giant, clumsy bumble bee has made me sentimental for the design. Maybe it’s just that there’s potential there. Thanks to the great Nan ships, we’ve got a pretty idea of what non-rigid airships are capable of. ZMC-2 only scratches the surface of what a metalclad could do; perhaps someday we’ll find out. With modern lithium-aluminum alloys being that much lighter, or the ‘black’ aluminum of carbon composites, we could probably build something exceeding Ralph Upton’s wildest dreams… if there was money to pay for it.
2026-03-10 19:00:22
There have been many questions about what direction Arduino would take after being bought by Qualcomm. Now it would seem that we’re getting a clearer picture. Perhaps unsurprisingly the answer appears to be ‘AI’, with the new Arduino VENTUNO Q SBC being advertised as ‘democratizing AI’ in the Qualcomm press release, although it also references robotics.
This new board is based around the Dragonwing IQ-8275 SoC along with an STM32H5F5 MCU, making it somewhat of a beefier brother of the previously covered Arduino Uno Q, which also offers an SoC/MCU hybrid solution. On the product page we can see the overall specifications for this new board, where the release date is specified as ‘soon’.
Its IQ-8275 SoC is part of Qualcomm’s IQ8 series, with eight 2.35 GHz ARM cores and an Adreno 623 GPU, paired with 16 GB of LPDDR5. The Cortex M33-based STM32H5F5 MCU comes with its own 4 MB of Flash and 1.5 MB of RAM, all on a board that’s significantly larger than the Uno Q and isn’t crippled by a single USB-C port as SoC I/O.
Although clearly more aimed at industrial and automation applications than the solution-in-search-of-a-problem Uno Q board, it remains to be seen whether this board will catch on with Arduino fans, or whether Qualcomm’s goal is more to break into whole new markets under the Arduino brand.
2026-03-10 16:00:19
If you think about it, you can’t be sure that what you see for the color red, for example, is what anyone else in the world actually sees. All you can be sure of is that we’ve all been trained to identify whatever we do see as red just like everyone else. Now, think about animal vision. Most people know that dogs don’t see as many colors as we do. On the other hand, the birds and the bees can see into ultraviolet. What would the world look like with extra colors? That’s the question researchers want to answer with this system for duplicating different animals’ views of the world.
Of course, this would be easy if you were thinking about dogs or cats. They can’t see the difference between red and green, making them effectively colorblind by human standards. Researchers are using modified commercial cameras and sophisticated video processing to produce images that sense blue, green, red, and UV light. Then they modify the image based on knowledge of different animal photoreceptors.
We were somewhat surprised that the system didn’t pick up IR. As we know snakes, for example, can sense IR. You’d think more sophisticated animals would have better color vision, but that seems to be untrue. The mantis shrimp, for example, has 12-16 types of photoreceptors. Even male and female humans have different vision systems that make them see colors differently.
Maybe you need a photospectrometer. You wonder if animals dream in color, too.
2026-03-10 13:00:00
Recently [TheRetroChannel] came across an interesting failure mode on a Commodore 1541 5.25″ floppy disk drive, in the form of the activity LED blinking just once after power-up with the drive motor continuously spinning. Since the Flash Codes that Commodore implemented and bothered to document start at 2 flashes (for RAM-related Zero Page), this raised the question of what fault this drive had, and whether a single flash is some kind of undocumented error code.
A cursory check showed that the heads were okay and not shorted, ruling out a common fault with the used floppy mechanism. Cleaning up the corrosion on IC sockets and similar basic operations were performed next, without making a change, nor did removing the ICs to induce it to produce the documented error codes, but this helped narrow down the potential causes. Especially after swapping in known-good ICs failed to make a difference. One possibility was that the drive was boot looping, as the activity LED is lit up once on boot.
Some probing around with an oscilloscope between the faulty and a working drive seemed to point to a faulty RAM IC, but while probing the faulty drive suddenly initialized successfully. After some more poking around it appeared that the drive was fine after it had a chance to warm up, which just deepened the mystery.
The drive did talk to a C64 with diagnostic cartridge at this point, but would often glitch out. Ultimately it appears that a dodgy IC socket and a few bad traces were to blame for the behavior, making it an ‘obvious in hindsight’ repair. The bottom of the PCB had some clear corrosion on it, but the affected traces were apparently still hanging on for dear life with the drive still initializing once warmed up.
