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Cake day: June 11th, 2023

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  • Watts are a unit of power. Regardless of voltage, if your appliance is drawing 3000 watts, it is heating up the same as any other device that draws 3000 watts.

    Wires are not sized on the number of watts they can carry. They are sized on the number of amps they carry. If a wire is sized for 10amps, and you are using 12v, you can only get 120 watts through it. Increase the voltage to 120v, and you can get 1200 watts through that same wire. Increase to 240v, and you can get 2400 watts from that wire. The higher the voltage, the less copper you need to carry it. You need thicker insulation to handle that increased voltage, but insulation is cheap. It’s more dangerous to humans who come into contact with the wires, but you can build in additional methods to restrict human contact, such as fancy plugs and sockets.

    The UK and Europe had a severe copper shortage when they rebuilt after WWII. They standardized on 240V to reduce the size of wires they needed in their homes. Instead of dozens of, low-amp circuits, they installed only a couple high-amp circuits for their entire home. They designed their household wiring so that the same circuit that powers the alarm clock on their nightstand is also used for their 3000-watt space heater.

    They further reduced copper consumption by using undersized wire in a “ring” circuit instead of properly sized wire in a “branch” circuit. Failures in ring circuits are extraordinarily dangerous, because there is no immediate indication that they have failed. Each outlet receives power from two sides of the ring; if one side fails, they draw all their power from the other side, overloading the ring.

    The US solution to these problems is intrinsically safer household wiring. We threw copper at the problem, because we had the copper to throw. But what we got in return was a vastly safer system. We managed to get a 240v system that only carries the risks of a 120v system.


  • The issue isn’t the voltage. It is the wattage. UK kettles draw 3kW. US outlets are (typically) only rated for 2.4kW. We can easily get dedicated 30A, 120v outlets that will provide 3.6kW.

    US 240v is not the same as UK 240v.

    The UK uses a single live phase, (240v with respect to ground), and a neutral (0v with respect to ground).

    The US uses two live phases. Each phase is 120v with respect to ground, but they are 180 degrees apart from eachother. Phase to phase is 240V, but either phase to ground is 120v.

    A UK kettle expects its neutral phase to be at the same potential as ground, which can’t happen in the US without a 1-to-1 transformer



  • The reality is that “tactical” and “strategic” are functionally meaningless adjectives when applied to weapons or systems.

    Theoretically, “tactical” refers to how a military unit engages another military unit. It is how a commander wins a battle against an enemy unit.

    “Strategic” refers to how a nation engages another nation. It is how a government wins a war.

    The term “tactical nuke” referred to something that a lower level commander could have been authorized to use under his own judgment. If Soviet tanks were rolling across Europe during the cold war, commanders may have been granted the discretion to use small nuclear weapons to halt their advance.

    Since the the doctrine of Mutually Assured Destruction was established, there has been no such thing as a “tactical” nuke. Any wartime use of a nuclear weapon of any kind demands an escalation to total annihilation. I used the term “tactical” ironically, to refer to a pre-“MAD” doctrine that can no longer exist.

    In declaring that conventional bombs cannot penetrate this fixed bunker, it seems that someone is pushing for unconventional warfare. The reality is that this bunker is not impenetrable. It shares the same weakness as any bunker: getting into and out of it. Bomb the entrances to the bunker, and it will take months or years to tunnel back in. Whatever they are doing inside it, they won’t be doing until they manage to dig it up again.









  • Smartphones are far too valuable to our efforts to be left at home. They are the difference between personally observing law enforcement atrocities, and being able to prove them. The media isn’t covering the protests. We need as much video as we can get. We need to be able to coordinate efforts, passing along troop deployments and numbers.

    While our main phones and accounts are probably linked to more information than law enforcement should ever be allowed to touch, burners add too much to our efforts to seriously consider not bringing them.


  • Ideally, that burner phone never goes anywhere near your home or any place you frequent from the time it is acquired until the time it is destroyed.

    Briar is a good messaging app for you and your group. It will work (to some degree or another) over bluetooth even after they shut down the cell towers. Keep posting information about law enforcement deployment numbers and locations.

    Airplanes.live provides unfiltered ADS-B data, useful for identifying and locating law enforcement aircraft, including drones.

    For uploading media, choose overseas fediverse instances for your account, which are not subject to US law, and won’t get shut down or raided by US law enforcement if you upload something they don’t like.

    I’ve been suggesting this everywhere: pick a dozen different protest locations, and share your list with everyone you meet. If and when law enforcement deploys in force at your current location, leave for another. Force them to constantly redeploy to multiple locations.




  • Rivalarrival@lemmy.todaytoScience Memes@mander.xyzPLASTICMAXXING
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    1 month ago

    For PFAS, yes, definitely. They’ve done studies on this, some are linked elsewhere in the thread. PFAS in the bloodstream is removed through either whole blood or plasma donation.

    For microplastics, I can’t say with absolute certainty, as I don’t know the concentration of microplastics in the blood, or if replacement blood/plasma contains microplastics. But, the mechanism is the same: extract polluted fluids; allow body to replace with non-polluted fluids. Concentration of pollution falls.



  • Yep! US allows plasma donation up to two times per week, with at least 48 hours between donations.

    Can’t donate plasma or blood for 8 weeks after donating whole blood, or 16 weeks after donating packed RBCs.

    Packed RBCs are basically the reverse of plasma donation. Instead of returning the RBCs and keeping the plasma, they take two units of RBCs and return the plasma.