For LED lamps, the color must be controlled at the emission source, not by filtering, i.e. by using an adequate combination of different conversion phosphors, to ensure a neutral white with a quasi-continuous spectrum, instead of a bluish white with great narrow peaks in its spectrum.
Unfortunately, the phosphors for the latter variant are much cheaper than for the former, so the lamp vendors have the incentive to make the lamps as bad as possible.
I ask only because I was retrofitting some navigation lights on a sailboat - and you can’t just upgrade the original incandescent bulbs with LEDs (or aren’t supposed to).
You are either supposed to get a special LED (backing up what you’re saying) or there are some new red/green enclosures that are differently treated / tinted to then put a “white” led into.
But I am so far from an expert on that, I may be completely misunderstanding.
When you use any kind of filter for a lamp, that stops a part of the light produced by the lamp, the part that has an undesired color.
So, at the same electric power consumption you have less light, or you can compensate by using a more powerful lamp, to get the same amount of light even with a filter. In both cases the energy efficiency becomes worse, i.e. the expenses for electric power are greater per output light.
On the other hand, when the manufacturer of the lamp controls inside the lamp the conversion of the light produced by the LED through fluorescence into the light that exits the lamp, there are chances to obtain a desired color and a certain shape of the emission spectrum by wasting less light than with external filters.
Filtering can correct a lamp color that is not the color that you want, but it cannot fill gaps in the emission spectrum of the lamp.
Cheap white LED lamps not only may have a too bluish color (or in some cases a too yellowish color), but their emission spectra may have gaps, so if a natural object from the environment happens to have a color that falls in a gap of the LED lamp spectrum, it will appear much darker than in daylight. This can cause orientation problems or difficulties in identifying certain things.
Where LEDs are used for signalling, not for lighting, so pure colors are desirable, much less problems exist, so e.g. the replacement in the red or yellow signal lights of cars, of the old incandescent lamps with color filters, with monochromatic LEDs without color filters, has posed no difficulties.
Pixel 1 was the ideal phone. Not too large. Completely flat back. Screen didn't bulge above the sides so you could drop it without shattering the screen. Google's design has only gone downhill since then. (The pixel 5 looks pretty nice, but it seems to have the bulging glass and the beginnings of camera bumps)
Anesthetics are very weird though. There's still a lot we don't know about how they work. They seem to act like you experienced, complete shutdown, for most people, which seems different from the states that people go into when unconscious or are near death usually.
And some people have a very different experience while under them - they are fully aware.
I had heard something unsettling about anesthesia that I could use verification or debunking.
The gist was that modern implementations suppress memory formation rather than induce unconsciousness. That you remain in some sense aware of what's happening but don't remember the experience. This is safer than traditional methods, but could potentially subject the patient to complex mental or emotional trauma.
It's both. In smaller doses, anesthetics like propofol will leave you groggy but semi-awake and able to respond to commands. But you won't be able to form long term memories so you won't remember afterwards. This is "twilight sedation" and is what you usually get when you get a procedure like an endoscopy or colonscopy. You are somewhat awake so that you can help reposition yourself and stuff if they need you to.
In larger doses, propofol will completely eliminate consciousness. This is "general anesthesia" and what you get when you go in for a major surgical procedure. You are completely unresponsive to any stimuli.
There are levels in between these too. Consciousness is a spectrum.
As far as I know, propofol doesn't make you feel particularly good or block pain. It just kind of makes you go away. So in addition, at all levels of anesthesia, they also typically give you a narcotic like fentanyl so that you aren't suffering. They aren't just letting you scream in pain and then erasing the tape afterwards.
As someone who has had a couple of procedures where they pushed the fentanyl into the IV before the propofol, I can 100% assure that pain was the absolute last thing I was feeling. Hell, I was still high as a kite after the propofol wore off when I got home. I was sitting at the kitchen table with a bunch of metal recently unscrewed from my leg bones thinking about literally nothing in the world beyond, "holy fuck this eggnog is the best beverage I've ever had in my life I wish I could drink it forever".
My recent colonoscopy used fentanyl. I wasn't loopy afterwards but we did (as directed) arrange to have someone else drive me home.
All in all, I really appreciate the loss of memory formation, since the most annoying part of these procedures for me is the boredom. Just splice all that out, thanks.
Before surgery, you're given an amnestic to help reduce immediate anxiety and avoid remembering going into the OR and getting prepped - which people don't generally enjoy.
Then you get the anesthesia, which puts you to sleep. They put you on a respirator, which - alongside helping your barely/non-working lungs - delivers a gaseous anesthesic to keep you asleep.
Because some reactions to pain are reflex, they may still work. And when you wake up, they don't want you to be in pain; especially if that's on the surgery table. So next, you get the analgesic opioids. Here you may also (if you didn't already) get paralytics to stop all muscle movement.
Rest assured that they are not YOLO-ing your pain and suffering. You are given a cocktail of drugs to make sure you are comfortable before, during, and after surgery.
General anesthetics is definitely one of the weirder parts of medicine. It seems to have developed mostly by trial and error over hundreds of years, but it has obvious huge benefits. Imagine any kind of internal surgery being attempted without it!
> you're given an amnestic to help reduce immediate anxiety and avoid remembering going into the OR and getting prepped - which people don't generally enjoy.
In that case, they don’t seem to work that well for me. Or maybe they do it differently here.
I always remember going into the OR and being prepped.
My anxiety for my last surgery was huge up until the moment I passed up. The best I got was the anaesthesist telling me it was normal for someone in my circumstances (I’d not had anxiety the last few times, so was very confused as to why I had so much this time, I was freaking for some reason)
To be fair, the use of midazolam is ultimately up to your healthcare professionals. It's not required and may be skipped if they think it would be harmful (age or respiratory / nervous system health) or is unnecessary (no anxiety). It's almost always given as an IV drip 10-ish minutes before wheeling you around to the OR, which is how you'd recognize if you got it. It's just a very common practice to give it by default for most people under 65-ish.
You may also require either a higher baseline dose than expected, and an onset of acute anxiety can actually affect dosing too. Both totally normal!
Either way, it's best to speak with your doctor leading up to surgery if that experience was upsetting. There's lots that can be done for dosage, supplemental medication, etc. Your comfort is important!
Do you know how that usually applies to people with addiction problems who elect not to receive anesthesia? Do they generally receive everything except the pain killers?
In some cases. My first experience with my wife in an ER (there have been many!), the doc came up to us and said exactly this. They needed to reposition a broken bone so it could be put in a cast before surgery to rebuild the wrist could be scheduled. Since it would only take a few seconds, instead of anesthesia they would use a medication that would let her be aware of the process, but she would forget it almost immediately after.
That was about 20 years ago. To this day, the last thing she remembers is lying on the table and saying "OK, let's git-er-done" and the next 5-10 minutes are missing.
>The gist was that modern implementations suppress memory formation rather than induce unconsciousness. That you remain in some sense aware of what's happening but don't remember the experience.
That's called twilight anesthesia and it's used for some procedures, not others. Usually used for stuff like wisdom teeth extraction and colonoscopies. Anything "major" and you're getting general anesthesia. You can ask what type of anesthesia you will be receiving (twilight or general).
The modern implementation is to use general anesthesia as little as necessary as it has numerous side-effects. Local anesthesia with improved selectivity is used if possible.
iiuc the OG Verizon Pixel has an unlockable bootloader, but the operating system doesn't let you unlock it, meaning root access should allow unlocking the bootloader.
some devices have a legitimately locked bootloader, which means you're SOL.
There are privilege escalation CVEs in bootloader code too. I remember unlocking some very early locked bootloaders this way in the early days of android.
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