Thanks, that's great to know! However, I also had to remove the high-CRI lights from some lamps because I found that they disturb my sleep if I have them on in the hours before bedtime.
I live in a 240-volt country, though, and I've never seen a dimmer switch here.
The sodium lamps are in fact safer for driving, because they preserve drivers' night vision, which improves visibility into the shadows, and because they cause less glare.
What they aren't good for is LED manufacturers' bottom line, and the lighting industry spent a lot of lobbying money to entice friendly politicians to heavily subsidize them with public infrastructure budgets, with those subsidies then misleadingly sold to the public as "efficient" and "environmentally friendly".
They're also not very good for reading the newspaper or doing critical color analysis. Thankfully such tasks do not need to be done at night in the middle of the street.
That would make sense. Otherwise I have no idea how people wouldn't have noticed how much more difficult it makes seeing anything outside of the sharp cutoff of the light cone (or, of course, for the person being dazzled on the other side).
It's not especially close to the peak sensitivity of the human eye (in either bright or dim conditions), but that's entirely okay. The goal should be to not affect people's level of dark adaptation.
If you use shorter ("bluer") wavelengths, as happens with white LEDs which consist of a blue LED + phosphor, it causes people's eyes to become bright adapted and effective night vision is ruined, causing people to have much worse vision in the shadows.
Also, if you use bluer light, the lights themselves cause dramatically more glare in peripheral vision, because the shorter-wavelength-sensitive "S" cone cells and rod cells are mostly absent from the fovea (center of the retina), and prevalent in the outer areas of the retina. This is why LED headlamps on cars are so obnoxious for drivers going the opposite direction.
Also, the LEDs clobber people's circadian rhythms and are extremely disruptive to wildlife.
Finally, the light pollution caused by the LEDs is much worse for seeing the stars, which is maybe not as important as the other harms, but still kind of sad.
> It's not especially close to the peak sensitivity
The sensitivity at sodium light is above 75% of the peak human vision (photopic) sensitivity.
This is a very small difference in light sensitivity. For example in the case of many sources of red light or blue light the sensitivity can be 5 to 10 times lower than the peak sensitivity.
Moreover, a perfect source of white light cannot achieve a better sensitivity than around 37%, i.e. less than half of the efficiency of an ideal source of monochromatic light at the sodium emission line.
Therefore the fact that currently LED lamps and low-pressure sodium lamps have about the same energy efficiency is caused by the LED lamps having a higher photonic efficiency and a lower threshold voltage (caused by a P-N junction voltage instead of the ionization potential of sodium), which compensate the disadvantage of using white light. A monochromatic LED lamp with the same color as the sodium lamps could have an energy efficiency at least double over the white LED lamps.
Red light would be even better for affecting the dark adaptation, but it has other disadvantages, like much worse energetic efficiency and lower visual resolution.
Yellow light a.k.a. amber light around the sodium emission line is a good compromise between energy efficiency, visual resolution and dark adaptation.
That's not necessarily a downside for traffic safety, though. Though I imagine someone must have studied the effects of various wavelengths on drivers...
My understanding is that cellophane generally does biodegrade in most settings. Polylactic acid (those cornstarch-derived bags) mostly biodegrades in hot enough compost or (after several years) in ambient-temperature soil, but not very well in cooler water (One study: "The half-life period of degradation [of polylactic acid in artificial seawater] is 12 [days at 90° C] or 468 days [at 60° C]").
Those temperatures are certainly hard to find in nature, outside of hot springs! Even if this is an error and we are talking about 90°F/60°F, the higher temperature is pretty much constrained to the tropics, so we're talking a year+ to degrade in real conditions. It is better than centuries, but not exactly rapid?
Yeah, I imagine it's considerably slower at ambient ocean temperature. Don't throw your PLA bags in the ocean or a river. Here's a different paper:
> For example, PLA is not biodegradable in freshwater and seawater at low temperatures [32,36–39]. There are two primary reasons for this: (i) The hydrophobic nature of PLA, which does not easily absorb water [40–42]. In aqueous environments, the lack of hydrophilicity diminishes the hydrolysis process, which is crucial for the initial breakdown of PLA into smaller, more degradable fragments. (ii) Resistance to enzymatic attack; the enzymes that degrade PLA are not prevalent or active under typical freshwater and seawater conditions [39,43,44]. The microbial communities in these environments may not produce the necessary enzymes in sufficient quantities or at the required activity levels to effectively breakdown PLA. Additionally, the relatively stable and crystalline domains of PLA can further resist enzymatic degradation.
Also:
> It should be emphasized that neat PLA cannot be classified as a completely biodegradable polymer, as it generates microplastics (MPs) during biodegradation.
BART is full of white-collar people who use it to commute and to travel around the area (alongside all sorts of other kinds of people, as you would expect for a broadly used service).
Ridership collapsed in 2020 because of the pandemic, for obvious reasons, but it's hard to really blame that on the service itself, or the riders.
Ridership has been gradually recovering since then. Total trips are now up to something like 70% of 2019 levels, and continuing to rise. Number of unique riders is actually above the 2019 level now.
Maybe you haven't tried riding BART again within the past several years?
I left SF ~2021, but even in 2019 it was kind of in a death spiral. Hopefully it's better now, loved it back when I lived there. But still hear mixed reports from friends.
For a bit of context, the Phaenomena was a book by Eudoxus (c. 400 BC) explaining the then-current knowledge of astronomy; unfortunately there are no extant copies. A poem (also called Phaenomena) by Aratus (c. 300 BC) made the content more accessible, and was extremely popular. The only surviving work by Hipparchus (c. 150 BC) is a critical commentary on these two books, and it only survived because it was bundled together with several other commentaries on Aratus' poem which were copied as a group. Hipparchus synthesized Mesopotamian astronomical observations and measurement techniques with Greek spherical geometry, founding the subject we now call trigonometry. All of his other works are lost, but much of the content of Ptolemy's Syntaxis (a.k.a. Almagest, c. 150 AD) was taken from Hipparchus' astronomical and mathematical works.
Any additional fragments of Hipparchus' works is of great interest to the history of mathematics and astronomy.
Sanger was originally hired to edit Nupedia, a web encyclopedia project with a strict peer review process, and only worked for Wales for about a year. Wikipedia was started as a side project (with Sanger contributing to the concept and some early organizing), but Wikipedia quickly became much more successful while Nupedia basically never got off the ground. My impression is that Sanger wanted to impose his own vision on Wikipedia, but couldn't because the community of volunteer editors disagreed, and when Wales stopped paying him as a full time Nupedia editor (Wales's company was tight on cash at that time), he stopped any involvement. This was long before most of the actual work of Wikipedia happened, and that should have been the end of the story.
But ever since, Sanger has been trash talking Wikipedia as a project and community ("broken beyond repair") and trying to undermine it. A few years later he started a competing project (which was predictably a total failure). For two decades he has been promoting himself as "cofounder of Wikipedia". Interviewer after interviewer asks the same lazy questions about the subject, without ever adding any new insight. (You can see that Sanger's ghost is chasing Wikipedia even into this discussion.)
It's beating a dead horse, and entirely off the topic of what the interview was supposed to be about. Answering the question clearly and accurately takes a lot of time and finesse, which is wasted on the interviewer and most of the audience. Wales clearly screwed up in that interview, but it's not hard to see where he's coming from, psychologically.
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