Gene Editing Spiders To Produce Red Fluorescent Silk

May 21, 2025 by Maya Posch 15 Comments

Regular vs gene-edited spider silk with a fluorescent gene added. (Credit: Santiago-Rivera et al. 2025, Angewandte Chemie)

Continuing the scientific theme of adding fluorescent proteins to everything that moves, this time spiders found themselves at the pointy end of the CRISPR-Cas9 injection needle. In a study by researchers at the University of Bayreuth, common house spiders (Parasteatoda tepidariorum) had a gene inserted for a red fluorescent protein in addition to having an existing gene for eye development disabled. This was the first time that spiders have been subjected to this kind of gene-editing study, mostly due to how fiddly they are to handle as well as their genome duplication characteristics.

In the research paper in Angewandte Chemie the methods and results are detailed, with the knock-out approach of the sine oculis (C1) gene being tried first as a proof of concept. The CRISPR solution was injected into the ovaries of female spiders, whose offspring then carried the mutation. With clear deficiencies in eye development observable in this offspring, the researchers moved on to adding the red fluorescent protein gene with another CRISPR solution, which targets the major ampullate gland where the silk is produced.

Ultimately, this research serves to demonstrate that it is possible to not only study spiders in more depth these days using tools like CRISPR-Cas9, but also that it is possible to customize and study spider silk production.

Plugging Plasma Leaks In Magnetic Confinement With New Guiding Center Model

May 20, 2025 by Maya Posch 8 Comments

Although the idea of containing a plasma within a magnetic field seems straightforward at first, plasmas are highly dynamic systems that will happily escape magnetic confinement if given half a chance. This poses a major problem in nuclear fusion reactors and similar, where escaping particles like alpha (helium) particles from the magnetic containment will erode the reactor wall, among other issues. For stellarators in particular the plasma dynamics are calculated as precisely as possible so that the magnetic field works with rather than against the plasma motion, with so far pretty good results.

Now researchers at the University of Texas reckon that they can improve on these plasma system calculations with a new, more precise and efficient method. Their suggested non-perturbative guiding center model is published in (paywalled) Physical Review Letters, with a preprint available on Arxiv.

The current perturbative guiding center model admittedly works well enough that even the article authors admit to e.g. Wendelstein 7-X being within a few % of being perfectly optimized. While we wouldn’t dare to take a poke at what exactly this ‘data-driven symmetry theory’ approach exactly does differently, it suggests the use machine-learning based on simulation data, which then presumably does a better job at describing the movement of alpha particles through the magnetic field than traditional simulations.

Top image: Interior of the Wendelstein 7-X stellarator during maintenance.

The Make-roscope

May 20, 2025 by Al Williams 11 Comments

Normal people binge-scroll social media. Hackaday writers tend to pore through online tech news and shopping sites incessantly. The problem with the shopping sites is that you wind up buying things, and then you have even more projects you don’t have time to do. That’s how I found the MAKE-roscope, an accessory aimed at kids that turns a cell phone into a microscope. While it was clearly trying to appeal to kids, I’ve had some kids’ microscopes that were actually useful, and for $20, I decided to see what it was about. If nothing else, the name made it appealing.

My goal was to see if it would be worth having for the kinds of things we do. Turns out, I should have read more closely. It isn’t really going to help you with your next PCB or to read that tiny print on an SMD part. But it is interesting, and — depending on your interests — you might enjoy having one. The material claims the scope can magnify from 125x to 400x.

What Is It?

The whole thing is in an unassuming Altoids-like tin. Inside the box are mostly accessories you may or may not need, like a lens cloth, a keychain, plastic pipettes, and the like. There are only three really interesting things: A strip of silicone with a glass ball in it, and a slide container with five glass slides, three of which have something already on them. There’s also a spare glass ball (the lens).

What I didn’t find in my box were cover slips, any way to prepare specimens, and — perhaps most importantly — clear instructions. There are some tiny instructions on the back of the tin and on the lens cloth paper. There is also a QR code, but to really get going, I had to watch a video (embedded below).

Continue reading “The Make-roscope” →

3D Printing Uranium-Carbide Structures For Nuclear Applications

May 19, 2025 by Maya Posch 11 Comments

Fabrication of uranium-based components via DLP. (Zanini et al., Advanced Functional Materials, 2024)

Within the nuclear sciences, including fuel production and nuclear medicine (radiopharmaceuticals), often specific isotopes have to be produced as efficiently as possible, or allow for the formation of (gaseous) fission products and improved cooling without compromising the fuel. Here having the target material possess an optimized 3D shape to increase surface area and safely expel gases during nuclear fission can be hugely beneficial, but producing these shapes in an efficient way is complicated. Here using photopolymer-based stereolithography (SLA) as recently demonstrated by [Alice Zanini] et al. with a research article in Advanced Functional Materials provides an interesting new method to accomplish these goals.

In what is essentially the same as what a hobbyist resin-based SLA printer does, the photopolymer here is composed of uranyl ions as the photoactive component along with carbon precursors, creating solid uranium dicarbide (UC₂) structures upon exposure to UV light with subsequent sintering. Uranium-carbide is one of the alternatives being considered for today’s uranium ceramic fuels in fission reactors, with this method possibly providing a reasonable manufacturing method.

Uranium carbide is also used as one of the target materials in ISOL (isotope separation on-line) facilities like CERN’s ISOLDE, where having precise control over the molecular structure of the target could optimize isotope production. Ideally equivalent photocatalysts to uranyl can be found to create other optimized targets made of other isotopes as well, but as a demonstration of how SLA (DLP or otherwise) stands to transform the nuclear sciences and industries.

Determine Fundamental Constants With LEDs And A Multimeter

May 17, 2025 by Tyler August 13 Comments

There are (probably) less than two dozen fundemental constants that define the physics of our universe. Determining the value of them might seem like the sort of thing for large, well funded University labs, but many can be determined to reasonable accuracy on the benchtop, as [Marb’s Lab] proves with this experiment to find the value of Planck’s Constant.

[Marv’s Lab] setup is on a nice PCB that uses a rotary switch to select between 5 LEDs of different wavelengths, with banana plugs for the multi-meter so he can perform a linear regression on the relation between energy and frequency to find the constant. He’s also thoughtfully put connectors in place for current measurement, so the volt-current relationship of the LEDs can be characterized in a second experiment. Overall, this is a piece of kit that would not be out of place in any high school or undergraduate physics lab. Continue reading “Determine Fundamental Constants With LEDs And A Multimeter” →

New Bismuth Transistor Runs 40% Faster And Uses 10% Less Power

May 16, 2025 by John Elliot V 38 Comments

Recently in material science news from China we hear that [Hailin Peng] and his team at Peking University just made the world’s fastest transistor and it’s not made of silicon. Before we tell you about this transistor made from bismuth here’s a whirlwind tour of the history of the transistor.

The Bipolar Junction Transistor (BJT, such as NPN and PNP) was developed soon after the point-contact transistor which was developed at Bell Labs in 1947. Then after Resistor-Transistor Logic (RTL) came Transistor-Transistor Logic (TTL) made with BJTs. The problem with TTL was too much power consumption.

Continue reading “New Bismuth Transistor Runs 40% Faster And Uses 10% Less Power” →

There are a number of metal cylinders displayed in a line. Each cylinder has a rectangular brass plate mounted to each end, and these brass plates stand upright, with the metal cylinders held horizontally between them.

Home-casting Thermoelectric Alloys

May 16, 2025 by Aaron Beckendorf 4 Comments

If you want to convert heat into electrical power, it’s hard to find a simpler method than a thermoelectric generator. The Seebeck effect means that the junction of two dissimilar conductors will produce a voltage potential when heated, but the same effect also applies to certain alloys, even without a junction. [Simplifier] has been trying to find the best maker-friendly thermoelectric alloys, and recently shared the results of some extensive experimentation.

The experiments investigated a variety of bismuth alloys, and tried to determine the effects of adding lead, antimony, tin, and zinc. [Simplifier] mixed together each alloy in an electric furnace, cast it into a cylindrical mold, machined the resulting rod to a uniform length, and used tin-bismuth solder to connect each end to a brass electrode. To test each composition, one end of the cylinder was cooled with ice while the other was held in boiling water, then resistance was measured under this known temperature gradient. According to the Wiedemann-Franz law, this was enough information to approximate the metal’s thermal conductivity.

Armed with the necessary data, [Simplifier] was able to calculate each alloy’s thermoelectric efficiency coefficient. The results showed some useful information: antimony is a useful additive at about 5% by weight, tin and lead created relatively good thermoelectric materials with opposite polarities, and zinc was useful only to improve the mechanical properties at the expense of efficiency. Even in the best case, the thermoelectric efficiency didn’t exceed 6.9%, which is nonetheless quite respectable for a homemade material.