It's a very interesting drug. There are a lot of concerns right now around PFAS in water supplies, for example, and Miebo/Evotears are pure PFAS (perfluorohexyloctane) that's instilled directly in the eye, giving you a dose somewhere around a million times higher than levels of concern in drinking water.
But it is absolutely revolutionary if you have dry eyes. Quotes include "I feel like my eye is actually too wet now"
That would be 1 liter of the active ingredient, not 1 liter of the eye drop. Also I don't believe that 1 ppt of this stuff is harmful when people are putting it directly in their eyes without severe harm.
Maybe, maybe not, maybe like teflon, the real poison is an intermediate ingredient, but I think its bullshit that we're just creating chemicals that linger in our water supply for eternity. You literally cannot find anyone in America without traces of the dangerous variant of the PFAS in their blood stream. Like every sip of water is some ridiculous dupont cocktail and we have to tolerate it because people have dry eyes and want non stick pans. Why cant you just use theratears?
Yes, but too slowly to matter. Average person consumes 1.5 liters per day of water, so if you live to 100 that's 55000 liters. At 1 ppt that's 1 ng / liter, or 55 ug over a lifetime. That's multiple orders of magnitude less than one drop of the stuff to your eye.
We will know after the drops have been out for over a decade, and actual real-world safety data studies get published.
Meanwhile, Restasis (cyclosporine A) (or a generic) works well, and doesn't have to be applied all day long, just two or three times a day. It does burn the eye initially, but it's not harmful, and the burning goes slowly away over time. It does take a few months to start working.
One thing you can be sure of is that the vats of PFAS being produced year after year for this drug aren't going away anytime soon. They're called "forever chemicals" for a reason.
Being dispersed in the environment is not the same as being concentrated into our drinking water supply with each measure resulting in 1ppt contamination of a trillion measures of water.
Largely firefighting foams, industrial and manufacturing, and landfill sources, but it's still an interesting problem. They don't really break down (that's why they're so useful both in a materials science sense and as a medication) which implies they'll stick around for an extremely long time.
You have absolutely no idea of what you're talking about. If you actually think the scare is overblown, I dare you to drink the whole bottle of that eyedrop.
> You have absolutely no idea of what you're talking about.
I do.
1. "PFAS" is a technically incorrect term.
2. It's ridiculously broad. Teflon is PFAS, sevoflurane is PFAS, and so on.
> If you actually think the scare is overblown, I dare you to drink the whole bottle of that eyedrop.
They literally use the same liquid to FILL THE EYEBALLS after retinal surgery. It's been approved for 25 years. A bottle of eyedrops has 4 milliliters of it, and it would do essentially nothing if swallowed.
The only relevant subdivision of PFAS is by chain length: small, medium, large. Even so, they all accumulate in the environment. Just because you with your short term selfish interest doesn't take any responsibility for the world at large, willing to totally destroy it for small personal gain, does not mean that others don't either. All PFAS are very harmful in the environment because it's like paperclips that keep being made but not ever being unmade. Medium and long chain are also harmful in the human body due to significant accumulation.
Teflon does not get a free pass. It is a toxin. The last I recall, it causes brain damage in children. There is a reason why sane people avoid nonstick cookware.
Don't confuse silicon oxide with a PFAS. It is quite the negligent and hazardous fallacy to put them in the same bucket. One has been around for billions of years. The other hardly has any research, and will take at least a decade more of data and research before we know what's it is capable of.
You are in no way smart enough to understand and consider all the pathways, uptake mechanisms, and consequences that are affected by the PFAS compound across all of biological life. Knowing just one or two over just a few years does not make you competent in it or qualified to make a broad safety comment.
Surely the sheer number and amount of different PFAs being distributed around the planet without knowing about long term effects is the ridiculous bit. The argument that because we dump a lot of it must mean that it's safe is just wishful thinking. Remember when lead was added to fuel and large amounts of lead were then pumped into the air? It had very noticeable effects on criminality in people.
The question is in the amount of them. PFOA and PFOS were literally dumped in kiloton quantities into the environment without much thought about their toxicity. They were used in firefighting foam that was just flushed into the sewer.
So yeah, removing that source of pollution is good. At the same time, the effects of even the worst offender (PFOS) are at most mild. Wildlife and epidemiological studies found significant effects only in areas that are at least billions of times more contaminated with PFAS than can ever accumulate in the environment if the waste streams are managed properly.
I have punctal plugs. They helped quite a bit, but for most people with dry eyes it's the lack of the lipid layer that is causing problems. Not the lack of water.
Punctual plugs are not as great as cauterization for multiple reasons. Firstly, plugs keep dropping off and getting lost over time. Secondly, they probably won't seal the gap fully.
The lipid emission will heal partially if one supplements vitamin A (10k IU) softgel, omega-3 triglyceride ester, taurine, and at least 4K IU of vitamin D3. It will heal enough to work. The D3 in this dose is for freezing autoimmune degeneration.
I have severe dry eye and I never need any drops except if I am wearing contact lenses.
Before committing to plugs, I tried temporary plugs made of (essentially) collagen. They completely seal the tear ducts, and they were just as effective as my current plugs. And my plugs have been in place for 10 years so far.
> The lipid emission will heal partially if one supplements vitamin A (10k IU) softgel, omega-3 triglyceride ester, taurine, and at least 4K IU of vitamin D3. It will heal enough to work.
Omega-3 acids help a tiny bit, and I'm getting D3 and A from multivitamins. And I'm doing all other recommended stuff: eyelid washing, compresses, IPL, etc. Over the years, I tried discontinuing all of that a few times, and my symptoms worsened as a result. But not by much.
PFHO is the most effective "artificial tears" type product. Nothing comes close to it.
Here we go again with the PFAS. It is the stuff to prefer the least, not the most.
> I'm getting D3 and A from multivitamins
That fails completely because they almost always don't have softgel oil-dissolve forms or the right dose at all. They're generally very far from it. It is exactly what leads to the autoimmune issue of dry eyes in the first place.
> That fails completely because they almost always don't have softgel oil-dissolve forms or the right dose at all
I tried tons of forms. My current ones are gel-filled capsules. Rather large ones, at that.
Sorry, but there's a huge amount of scholarly literature on this question. I've read tons of it over the years, and there is NO magical supplement that does anything but mildly improve the situation.
Forms alone won't accomplish anything if the dose isn't correct. With regard to vitamin A, some people confuse it with beta carotene, with the latter not working so well for this effect. Vitamin A even has evidence backing it as per PMC6462169. It does take a few weeks to begin to work. Even mild improvements stack up. It may not eliminate the need for an additional intervention, but it can mean the difference between whether the additional intervention will work or fail.
Visomitin (Emoxipine/Mexidol) eye drops are a Russian-developed antioxidant medication known for treating dry eyes, fatigue, radiation damage, and improving vision, working to protect eye cells from damage (oxidative stress), but it's not widely available or FDA-approved in the US, requiring international purchase or specific prescriptions, often used for cataracts or post-surgery recovery, focusing on cell protection rather than just lubrication like many Western OTC drops.
> Visomitin (Emoxipine/Mexidol) eye drops are a Russian-developed antioxidant medication known for treating dry eyes, fatigue, radiation damage, and improving vision
I wouldn't recommend it. A quick search shows that it's not proven to do anything at all but it's also advertised as being the cure for parkinson's, asthma, back pain, high cholesterol levels, anxiety, blood clots, glaucoma, and Huntington’s disease while also making you smarter and improving your memory. This sounds like classic snake oil. Something I'd expect to see being sold alongside Horny Goat Weed and kratom at a gas station rather than an actual medication dispensed by a pharmacist. As fucked up as the American healthcare system is I guess you really have to hand it to Russia sometimes.
I'd happily be proved wrong, but all the usual red flags are there. About the best that can be said for it at the moment is that there doesn't seem any more evidence that it's harmful than there is for it being helpful. Hopefully it gets the research to back up the claims. It certainly purports to be effective for conditions there's plenty of interest in developing effective and safe treatments for so you'd think that nations around the globe would be eager to look into it.
The West and the globe doesn't work that way. There is little to no money in something that can't be patented. For this reason, at least no pharma firm will pay for any trials with it, and so it can't easily ever get FDA approved. Naivete does not help.
We're going to see something like the way Boeing was hollowed out by taking over McDonnell Douglas I'd guess. I have no insider knowledge but WB doesn't seem like a poison pill you can take without adverse impact.
I'd guess that there's markedly different margins on lootboxes versus running the entire steam store.
I'd be surprised if lootboxes only earned them 6% of profits, I'd guess they're something like 10% or more, assuming that they're like 90% margin and the regular steam store side is more like 50% margin (which is still absurd, for what it's worth).
It's even easier if you implement your Forth or Lisp interpreter in Forth or Lisp (both map to each other surprisingly well). Metacircular evaluator and be there.
"The Medieval Latin practice of writing -ch- for -c- before Latin -r- also altered anchor, pulchritude, sepulchre. The -y- is pedantic, from the former belief that the word was pure Greek."
I was very impressed by the modest little fab I worked at having thousands of lead acid batteries for momentary takeover, and 8 five-megawatt locomotive engines for longer term redundancy. Apparently their steady state usage was 25MW, which allowed still having a hot spare and concurrent downtime for two of the locomotive generator units.
> How can developed economies where populations levels have plateaued continue to be expected to post positive GDPs (and therefore add net new goods and services) yoy?
Think about the unsatisfied needs and desires most people have. In extremely low income areas, it may be a roof over your head or knowing where your next meal comes from. Moving up a tier, it might be the ability to send your children to education or better clothing. In wealthier areas it might be things like a better car or higher quality food even though you're not in danger of going hungry. For the extremely wealthy it might be more leisure time, art, and new experiences.
When GDP increases, broadly, those are the areas you see expand. Looking at life today in a baseline American household, the things which are mass produced are far more available and affordable than they were a century ago - in the 1930s households spent about 10-12% of their income on clothing.
Sadly, the rate of improvement for non-mass-produced items like college tuition, medical care, and especially housing has ballooned compared to median income, so life doesn't feel inexpensive, certainly, but GDP has a lot of room to grow in a lot of areas.
As a ceramicist it'd be difficult to 3d print with because the kinds of temperatures you can reach even with heavily fluxed silica is still extremely high. I fire bisque at cone 04 which is approximately 1060C / 1940F and that's considered low fire, only extremely heavily fluxed glazes (usually pure frit or equivalent) melt at that level.
Putting 3d printing concepts on the table, though, you could definitely see something like a sintered bed printer using a laser to print it, but then you wouldn't get anything close to the standard FDM style print.
Fundamentally, if the nozzle temperatures can't possibly withstand what they are extruding without eroding, we can either:
- balance an exothermic reaction (self-propagating high-temperature synthesis) to occur just after leaving the nozzle
- externally apply the heat with laser or plasma arc etc
The limit of externally applying heating is when the heat flux has to be so high that some material vaporizes and pops. An exothermic reaction within the material overcomes this limitation.
The other alternative is like current state of the art 3d printing ceramics - you either replace some high percentage of the filament with clay and fire it as a post processing step and it burns off the plastic, or print a clay/water slurry directly and fire it after drying.
But I don't think we'd end up with the basalt being very filamentous.
If the binder that gives you something printable at low temperature doesn't integrate into the final result through chemical reaction, you are almost assuredly going to get a high porosity mess where the binder had to vaporize out.
If instead the binder and precursor can melt, react, and expand into a solid that precipitates out because of a super high melting point, the expansion will ensure that you get a fully dense part that can be machined back down.
Yes, but I think for 3d printing purposes you'd probably have insufficient fusion even at those temperatures. I print well above the melting point or you get layer separation. It'd definitely be a fun experiment to try though!
"Well above the melting point" usually means 60° or less, which is more significant going from 195° to 245° than going from 650° than to 710°.
These temperatures make it a significantly trickier engineering problem; ideally, your nozzle would retain its shape at those temperatures despite containing a lot of pressure, not be corroded by the lava you're squeezing through it, not be abraded by any zircon grains that snuck into your melt, and not oxidize on the outside from the temperature when it's exposed to air. I'm pretty sure you could make a zirconia nozzle work if it was thick enough, but I don't think ruby, sapphire, or diamond would last very long. Probably something like inconel would also work, but I don't think 304 or 316 would.
It'd be a lot more than 60C - the goal is to keep the material from cooling past the melting point by the time it's been deposited, and thus the important factor is the rate of energy loss, which is dramatically accelerated in a temperature differential of, say, 650C instead of say 145C - so I'd guess you'd want about 150C - 300C difference.
I'd bet inconel and other high temperature alloys would be eroded very quickly, anything that's fluxed enough to melt below 1000C is going to be extremely corrosive. Hot molten sodium hydroxide levels of corrosive. Fun to think about though, a serious materials challenge for sure.
I'd guess that it's a lot easier to maintain the whole build chamber at 500° than to maintain the hotend at 850°, but I haven't tried it.
Felsic lavas (and magmas) which melt at those temperatures do not typically contain a lot of alkali oxides, but they do contain some. See https://en.wikipedia.org/wiki/Calc-alkaline_magma_series#/me... However, ferrous and quasi-ferrous alloys like inconel are among the best choices for alkali corrosion. For example, table 4 in Birgitte Stofferson's dissertation https://orbit.dtu.dk/en/publications/containment-of-molten-n... gives an inconel corrosion rate of 1.06 mm per year in molten NaOH at 600°, which happens through oxidation from oxygen dissolved in the melt. Monel 500 corroded only 5.06 mm per year at 700°.
If you were trying to keep a 100μm hotend aperture within a ±10% tolerance, you could start with a 95μm aperture and replace the hotend when the aperture had expanded to 110μm. At 1mm/year those 15μm would be 5 days of printing time, which seems like a usable hotend lifetime. Presumably printing in lava rather than 100% NaOH would extend the lifetime further.
I think that if most of the things in the vacuum chamber are at room temperature, while the lava filament is at 700°, that won't substantially reduce the radiative heat loss. If almost everything inside the vacuum chamber that isn't mirror-coated is at something like 500° or 600°, I think it would work. Maybe that could save you from having to keep the walls themselves at 500° or 600°.
I also assume directional solidification is really important for basalt, like for glass fibers and others. That's hard to achieve for bulk objects but easy for fibers.
I've had better results with managing my own clusters on metal instances. You get much better performance with e.g. NVMe drives in a 0+1 raid (~million iops in a pure raid 0 with 7 drives) and I am comfortable running my own instances and clusters. I don't care for the way RDS limits your options on extensions and configuration, and I haven't had a good time with the high availability failovers internally, I'd rather run my own 3 instances in a cluster, 3 clusters in different AZs.
Blatant plug time:
I'm actually working for a company right now ( https://pgdog.dev/ ) that is working on proper sharding and failovers from a connection pooler standpoint. We handle failovers like this by pausing write traffic for up to 60 seconds by default at the connection pooler and swapping which backend instance is getting traffic.
But it is absolutely revolutionary if you have dry eyes. Quotes include "I feel like my eye is actually too wet now"
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