No, its not; not that the implicit equation of “how it used to be” with “how it ought to be” is valid to start with.
> We had a War Department. Rebranding to Defense was a PR move to hide what was really happening.
No. We had a War Department that was the agency responsible for the Army, including what was then the Army Air Forces, and a Navy Department that was the agency responsible for the Navy including the Marine Corps. Splitting and rebranding the former to the two Departments of the Army and Air Force was done to simultaneously more accurately reflect its responsibilities and to address the growing significance of air power.
This split was simultaneous with the old and now split up War Department and the old but keeping its name Navy Department being subordinated to the new consolidated military establishment named the Department of Defense, but the Defense Department wasn’t a new name for the War Dpartment, it was the name for a completely new thing placed above the older, separate military departments.
It's not side-effects that are in question here, it's the intended effect. When it comes to its effectiveness at blocking UV, there should be a better way than just "apply some to a dozen random volunteers and time how long it takes before they get a sunburn".
In my imagination, the lab would have some a testing process that spreads a precisely-controlled volume over a standard surface area, textured to be similar to skin, then measures UV transmission percentage vs wavelength with a diffraction grating and photocell. Or something like that!
> In my imagination, the lab would have some a testing process that spreads a precisely-controlled volume over a standard surface area, textured to be similar to skin, then measures UV transmission percentage vs wavelength with a diffraction grating and photocell. Or something like that!
With this approach, how would you measure the effectiveness of the sunscreen when it's been absorbed by the skin (which is necessary for the sunscreen to work properly - that's why they always say to wait ten minutes after applying before going out into the sun)?
There's a reason in vitro and in vivo are both studied for clinical trials of medications. Sunscreen isn't any different: you're using a product making a specific claim about a clinical outcome, so that needs to be tested.
> With this approach, how would you measure the effectiveness of the sunscreen when it's been absorbed by the skin
You can eliminate the "can't possibly work" cases much faster and cheaper.
More importantly, it is cheap enough to be always used as a baseline verification when human testing is so expensive that it can only be used as a random sample double-check.
It's like unit testing vs full user acceptance testing. You can and should do both, but the latter isn't for every PR.
> More importantly, it is cheap enough to be always used as a baseline verification
> It's like unit testing vs full user acceptance testing. You can and should do both, but the latter isn't for every PR.
You say all this as if it weren't already happening. OP was surprised human testing was being conducted at all, not that non-human testing wasn't being done (which is a claim nobody made, and which isn't true).
IDK. There are tons of things that can happen on (and in importantly for sunscreen) human skin. (Skin sweats in the hot sun, but of course your skin can have various reactions to and with chemical) This seems like the simplest and most effective method for testing effectiveness (should probably come up with some other tests for carcinogenic properties though)
The problem is that testing has to be reproducible but usage doesn't.
I've actually been a test subject for sunscreen here in Australia. It involved having sunscreen put on different parts of your body, hopping into a Jacuzzi for an hour or so, then being zapped with UV on both sunscreened and clear skin.
The testing here is not just that it is safe on skin, but the SPF test itself is done by slathering it on humans and exposing them to light to determine a rating.
If you look at the skin as a protective barrier, then that makes sense, but its ability to absorb cosmetics depends on a lot of factors. First off, what makes a product more absorbable (i.e. influence percutaneous absorption)? Molecular size (typically smaller than ~500 Daltons). Lipophilicity (fat-solubility). Formulations and vehicle, e.g. emulsions (oil-in-water, water-in-oil) can improve penetration depending on balance. There are alcohol-based solutions that enhance delivery of certain actives but may irritate. There are other penetration enhancers such as propylene glycol, ethanol, fatty acids, which disrupt the skin barrier slightly to allow deeper diffusion. Heck, even salicylic acid does that.
There are a lot of other factors here, such as your skin's condition (hydrated skin absorbs better), damaged or inflamed skin even more but sometimes to unsafe levels and it is typically contraindicated for almost all cosmetics.
In any case, most cosmetic ingredients act locally (i.e. not supposed to enter into systemic circulation like transdermal drugs), improve hydration, texture, and/or appearance by altering the stratum corneum or slightly beyond. Systemic absorption is limited unless specifically engineered to do so, such as nicotine patches, hormone creams, fentanyl patches, etc. I mentioned this below "transdermal drug delivery".
The curious should look up the differences between cosmetic absorption vs. transdermal drug delivery as well. For example, cosmetics are not intended to penetrate into the bloodstream, hence the surface layer depth. To give you percentages, typically >90% remains on skin surface, but it also depends on what you want to achieve, because for example hyaluronic acid in creams are of large molecule (~3000-5000 Da), meaning it essentially 0% penetrates. It hydrates only by trapping water on the skin surface. Important to note here that sometimes this is exactly what people want, i.e. this surface hydration is what gives the "plump, glowing skin" effect people expect, so if the goal is hydration and surface smoothness, then large HA is ideal (surface action is enough), but if the goal is true wrinkle reduction or anti-aging, then surface HA alone is not sufficient. This is why companies combine HA with retinoids, peptides, or vitamin C, which act deeper and can influence collagen production. If the goal is long-term structural change, then you can have injectables (such as dermal fillers, which are being used for enlarging the lips, for one).
Transdermal Drug Delivery on the other hand are supposed to enter the bloodstream so drugs delivered through skin (e.g., nicotine, fentanyl, estradiol patches) are engineered to bypass the stratum corneum barrier. They use optimized molecular size, solubility, enhancers, and occlusion. If you want percentages here as well, I would say 20-95% systemic absorption of applied dose, but it depends on a couple of factors I have previously mentioned.
Just to stay on topic: sunscreens require only surface layer depth of absorption only, and in fact, many products work at this level. Their effectiveness depends heavily on formulation, proper application, and reapplication. Sunscreens do work when used correctly, they significantly reduce UV damage, premature aging, and skin cancer risk, BUT you must apply it properly and reapply often. You should combine with shade, too.
I have absolutely zero knowledge about the science and/or biology of skin, I read your post expecting it to end with something stupid like "don't know, I made all of this up". I'm glad it didn't!
I love HN because, for every snarky comment that's made or said on a misunderstood, or incorrect basis of knowledge that would set off an alarm on QI, followed by a stern telling off by Stephen Fry.
There's some one like you, who has an endless pit of knowledge to aritculate or better inform with a whole lot of insight thrown in for good measure. Thank you, your post's awesome. :)
Small edit: I immediately thought "Your skin can't be that good as a barrier, nicotine and caffeine patches work through the skin?" when I saw the post you replied to, and loved that you made reference to it too.
I just woke up when I saw the submission, and when I scrolled through the comments I saw the one to which I replied because it did provoke me enough (you can even say it triggered me :D) to make such a reply.
I am glad it was a useful read to some at least! Of course if there are mistakes, I expect them to be called out and corrected, it has been a while since I last studied this. :)
> to articulate or better inform
I hope I did it right, I was still just waking up, and English is not my first language to begin with, but to see you write this does make me glad I made the comment.
FWIW your comment is quite motivating, thank you again, I mean it. You made my day. :)
(I try to encourage or motivate people as well who articulate my thoughts way better than I could ever hope to!)
Aww dude, nothing to thank me for, thank you though! :)
I had no idea English was your second language! That's awesome.
I'm dyslexic so language is really hard for me, I have to put a lot more effort than most. I'm pretty intolerant of people who get annoyed at others when spelling or grammar is incorrect when we don't know their personal context (I had to triple check my spelling of grammar at least three times there XD).
I never got that impression from your post English wasn't your first language though! But I also wouldn't have stepped in to correct you even if you had. I nearly always find my own errors after a second or third visit, if I want cristicism of how I wrote something. I'll ask for it. If I didn't. I don't. I assume the same for everyone else.
It didn’t ruin his life. Having an unstable childhood due to a mentally ill mother and later developing paranoid schizophrenia and a drug addiction (common with schizophrenia) is what ruined his life.
Except they didn’t. A proper municipality decision would have been discussed publicly with advance notice. This is like the board of directors of Toyota deciding to stop selling to the US without advance notice without input from the shareholders, the US, or advance notice.
It is 100% disingenuous. In no municipality in America is the source of water not considered a long term source where change comes with months of notice. In no municipality is said change executed in a meeting without prior notice to the public with public commenting allowed.
No doubt you mean well. In some cases it’s obvious- low memory machine can’t handle some docket setup, etc.
In reality, you can’t even predict time to project completion accurately. Rarely is a fast computer a “time saver”.
Either it’s a binary “can this run that” or a work environment thing “will the dev get frustrated knowing he has to wait an extra 10 minutes a day when a measly $1k would make this go away”
I agree that's what it should be, but that absolutely not what it is and it hasn't been that way for many years. People treat LinkedIn like Facebook and post their opinions on things.
Most of the potentially worrisome stuff I've posted has been comments responding to other peoples' posts. I went and deleted nearly all of those, though.
Food control is easy but we don’t actually want it.
1. Prohibit large companies from using their size to negotiate prices, like how it used to be
2. Stop farm subsidies for all but the most critical areas. If you want to make food available to the poor, give them food stamp cards, but further restrict junk food. Supply side subsidies just create excess crops which lead to everyone trying to use cheap corn in some way. This cheap corn is then used to destroy local farmers in Latin America, further increasing illegal immigration and the power of cartels over a newly destitute population.
