How Gut Bacteria May Affect The Outcome Of Cancer Immunotherapy

In the ongoing development of cancer immunotherapy, as well as our still developing understanding of the human immune system, there’s always been a bit of massive elephant in the room. The thing about human bodies is that they’re not just human cells, but also consist of trillions of bacteria that mostly live in the intestines. What effect these bacteria have on the immune system’s functioning and from there on immunotherapies was recently investigated by [Tariq A. Najar] et al., with an article published in Nature.

The relevant topic here is that of antigenic mimicry, involving microbial antigens that resemble self-antigens. Since these self-antigens are a crucial aspect of both autoimmune diseases and cancer immunotherapy there is considerable room for interaction with their microbial mimics. Correspondingly these mimics can have considerable negative as well as positive implications, ranging from potentially triggering an autoimmune condition to hindering or boosting cancer immunotherapy.

In this study mice were used to investigate the effect of such microbial interference, in particular focusing on immune checkpoint blockade (ICB), which refers to negative feedback responses within the immune system that some cancers use to protect themselves. In some immunotherapy patients ICB inhibiting using e.g. anti programmed cell death protein (anti-PD-1) treatment does not provoke a response for some reason.

For the study mice had tumors implanted and the effect of a particular microbe (segmented filamentous bacteria, SFB) on it studied, with the presence of it markedly improving the response to anti-PD-1 treatment due to anti-gens expressed by SFB despite the large gut-skin distance. Whether in humans similar mechanisms play a similarly strong role remains to be investigated, but it offers renewed hope that cancer immunotherapies like CAR T-cell immunotherapy will one day make cancer an easily curable condition.

Photographing Rocket Chute Deployment At 10 Km

For those who haven’t been following along, [BPS.space] aka [Joe] is on a journey to launch a home-built rocket past the Kármán line where it will officially reach outer space. But one does not simply launch a rocket to outer space on the first try. The process is long and involves not only building a series of rockets, but designing and building propellant mixtures, solving aerodynamic problems, gaining several model rocket certifications along the way, and a whole host of other steps. He’s also documenting the entire process on video as well, which involves some custom camera work like this rocket selfie camera which will take an image of his rockets at apogee.

Like most problems in high-power rocketry, extremely tiny problems have a way of causing catastrophic failure, so every detail needs to be considered and planned for in the final design. For a camera that needs to jettison itself from the rocket at a precise moment after experiencing an incredible amount of forces, this is a complicated problem to solve. The initial design involves building a sled for a small deconstructed GoPro which uses springs and a servo to launch itself out of the rocket. The major problem with the design is that even the smallest torque on the sled will cause the camera to point in a random direction by the time it’s far enough from the rocket to take a picture. [Joe] tried a number of design iterations but could not get these torques to vanish.

One of the design limitations with this camera is that it won’t have any sort of parachute or tether itself to the rocket, so it will hit the ground at its terminal velocity. To keep that velocity down and improve survivability chances of the footage, the mass has to stay low. Eventually he settled on a semi-active control system by mounting a brass weight on a small motor, giving the camera module enough stability to stay pointed at the rocket long enough to take the video. Even though it hasn’t flown yet, admitting his first design wasn’t working at compromising on this solution which adds a bit of mass seems to be a good design change. We’ve been following along with his entire process so be sure to check out his actual rocket motor builds and teardowns as well.

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Growing Aluminium-Copper Alloy Crystals Using Hydrogen

Having molten aluminium interact with atmospheric water forms a source of hydrogen which can be rather problematic if you’re trying to cast aluminium parts. As the molten metal cools down, the dissolved hydrogen is forced out, creating bubbles and other flaws that make aluminium foundries rather upset. While you can inject inert gases to solve the problem, you can also lean into this issue to make some rather fascinating aluminium crystals and geodes, as [Electron Impressions] recently did.

The key here is to use a eutectic Al-Cu alloy at around 45% Cu by weight, as this alloy readily forms large crystals as it cools down. With hydrogen injected into the molten metal, this hydrogen forms large bubbles inside the cooling metal with crystals clearly visible.

A way to create proper geodes involves very slow cooling and pouring off the still molten metal before the eutectic point is reached. As can be seen in this video, this creates a rather impressive looking geode after it’s been smashed open. This also gives a good clue as to how these geological features form in nature, although one does not typically observe Al-Cu alloy geodes in the wild.

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DIY Weather Stations Report In From Chernobyl

You’re probably not going to hang out around Chernobyl any time soon. Still, knowing the conditions there can both satisfy your curiosity and provide scientific value. To that end, [Yury Ilyin] has spent the last couple decades installing homebrew weather stations across the Exclusion Zone for his own interest. 

The remote weather stations that [Yury] builds all follow a similar design. Each runs on three 18650 lithium cells, charged via a small solar panel. Most of these cells were salvaged from old laptop battery packs. These cells are used to power a GPRS or WiFi communications module, along with a temperature, humidity, and pressure sensor, and a Geiger counter, because, well… it’s Chernobyl.

He has been lucky enough to keep costs down by finding an old generation GPRS SIM card that could be cloned and used across multiple devices, and thus far has had no trouble receiving signals from his many distributed stations. He’s been able to use his sensor network to track the gradual decline of radioactive emissions in the area from Cs-137, as well as keep an eye on the local weather conditions in an area few ever tread.

[Yury] has built over two dozen of these devices, and several have passed the test of time—with the lithium cells and cellular hardware surviving both high and freezing temperatures as well as the ravages of rain and time. He’s continued to refine the design over the years, starting out with an ATmega644 running the show, and later upgrading to STM32 microcontrollers.

We’ve explored distributed radiation sensor networks before, too, as well as many a remote weather station. Continue reading “DIY Weather Stations Report In From Chernobyl”

Flash Joule Heating Recovers The Good Stuff

Rare earth materials are a hot button topic these days. They’re important for everything from electric vehicles to defence hardware, they’re valuable, and everyone wishes they had some to dig up in their backyard. Lithium, too, is a commodity nobody can get enough of, with the demand for high-performance batteries grows each year.

When a material is desirable, and strategically important, we often start thinking of ways to conserve or recycle it because we just can’t get enough. In that vein, researchers have been developing a new technique to recover rare earth metals and lithium from waste streams so that it can be put back to good use.
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DIY Nuclear Battery With PV Cells And Tritium

Nuclear batteries are pretty simple devices that are conceptually rather similar to photovoltaic (PV) solar, just using the radiation from a radioisotope rather than solar radiation. It’s also possible to make your own nuclear battery, with [Double M Innovations] putting together a version that uses standard PV cells combined with small tritium vials as radiation source.

The PV cells are the amorphous type, rated for 2.4 V, which means that they’re not too fussy about the exact wavelength at the cost of some general efficiency. You generally find these on solar-powered calculators for this reason. Meanwhile the tritium vials have an inner coating of phosphor so they glow. With a couple of these vials sandwiched in between two amorphous cells you thus have technically something that you could call a ‘nuclear battery’.

With an approximately 12 year half-life, tritium isn’t amazingly radioactive and thus the glow from the phosphor is also not really visible in daylight. With this DIY battery wrapped up in aluminium foil to cover it up fully, it does appear to generate some current in the nanoamp range, with a single-cell and series voltage of about 0.5 V.

A 170 VAC-rated capacitor is connected to collect some current over time, with just under 3 V measured after a night of charging. In how far the power comes from the phosphor and how much from sources like thermal radiation is hard to say in this setup. However, if you can match up the PV cell’s bandgap a bit more with the radiation source, you should be able to pull at least a few mW from a DIY nuclear battery, as seen with commercial examples.

This isn’t the first time we’ve seen this particular trick. A few years ago, a similar setup was used to power a handheld game, as long as you don’t mind waiting a few months for it to charge.

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Ski Slopes For Laser Imaging

Lasers are cool and all, but they can be somewhat difficult to control at times. This is especially true when you have hundreds, thousands, or millions of lasers you need to steer. Fortunately, the MITRE Corporation might have created exactly what’s needed to accomplish this feat. While you might expect this to be done in a similar fashion as a DLP micro mirror array, these researchers have created something a bit different.

A ski slope like a MEMS array is used to contort light as needed. Each slope is able to be controlled in such a way so precise that entire images are able to be displayed by the arrays. This is done by using a “piezo-opto-mechanical photonic integrated circuit” or (POMPIC). Each slope is constructed from SiO2, Al, AlN, and Si3N4. All of these are deposited in such a way to allow the specific bending needed for control.

While quantum computing hasn’t hit these slopes yet, that doesn’t mean you can’t look into the other puzzles needed for the quantum revolution. Quantum computing is something that people have been trying for a long time to get right. Big claims come from all the big players. Take Microsoft, for example, with claims of using Majorana zero mode anyons for topological quantum computing.

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