This is because wind and tire rolling noises take over any engine noise at > 15mph, and because electric vehicles are usually substantially larger and heavier than its counterparts.
Those whooosh noise of a car passing is mostly the sound of an 1.75t object rolling through displacing air.
One example: https://www.toi.no/getfile.php/1340825-1434373783/mmarkiv/Fo...
Tire noise, possibly, as the tire is holding that mass.
I also don't feel like electric cars are more loud, at least at moderate speeds. I always had the impression that they're a lot more silent inside cities. Maybe on a highway that would be different, I can't say.
The biggest offenders of background noise are obviously trucks though.
I must have missed seeing the commercial launches of all those bigger than Chrysler C's bigger than Toyota Landcruiser's, bigger than Ford F150's etc that must have been selling like hotcakes.
That claim alone is enough to discount your entire comment.
> the best way to maintain brain health was to stay physically and mentally active, eat a healthy balanced diet, and keep your weight, cholesterol and blood pressure in check.
You don't need HEPA filters if the air circulates, because what doesn't get caught on one round probably gets caught on the next. Five rounds at 75% is as good as 99.9% once.
The HVAC system just needs enough filtering to avoid impacting its operation. Any additional air particulate removal should be done separately.
In any case, noise isolation can make a huge difference.
It's odd that the Guardian neither links to it, nor even names the researchers or their institution.
I wouldn't be surprised further study will show the last bit is due to earplugs at higher noise levels, resulting in a relative reduction in sleep disruption. Unless they also took earplug use into account already, then I'm genuinely curious what could be the reason
Not that I don't think the science is good, I'm sure they do and the article says they do, but I struggle to see how you can isolate noise from particulate exposure: they'd have semi identical square law dropoff by distance and volume.
1. Electric trains wont generate diesel particulate, but will generate road noise.
2. It's relatively straightforward to measure pollution and noise, so you can do analysis to try and separate them.
In many situations these would not be correlated exactly. For example, terrain, wind patterns, noise dampening structures, etc.
They don't generate diesel particulate, by they do generate "other PM10 and finer particulate", from the brakes for example.
In Paris there's a lawsuit against the RATP (local transit authority) for particulate pollution inside the stations. [0]
There's also the fact that, at least in Paris, some metros are running on tires. For those that run on metal wheels and rails, some turns are quite sharp, and you can hear the screeching of the metal. This is likely to contribute to particulate pollution.
I suppose for overground trains, this is less of an issue.
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[0] https://www.rfi.fr/en/france/20210323-french-ngo-sues-paris-...
The other problem is that people that live near noise are poorer. Did they control for wealth?
These epidemiological observational studies are so hard to take seriously. I get why so many of them are done though. It's a relatively lower effort way to get publications out the door, all you need is a dataset and a few days in python.
“The results are strengthened by the authors controlling for levels of traffic pollution, which was recently shown to be associated with dementia as well as other diseases.”
In the region of Toulouse, France, "vent d'Autan", a strong wind that blows in that region is called "vent qui rend fou", the wind that drives people crazy. It is a bit of folk knowledge that seems to be verified: crimes rates are higher, people and animals are more agitated, ect...
And it is not the only occurrence where strong wind is associated with madness.
Nobody knows how to interpret it. 40% is a huge effect size! (I doubt aspirin shows up as more effective against headache.) Is it the tetanus, the diphtheria, the pertussis antigen? Something else they put in the vaccine?
You can get a Tdap at any pharmacy, on demand. I did.
A correctly-designed RCT can give more confidence in a result, particularly to non-statisticians, but very large effect and cohort sizes should not be ignored. We could tell just from the topical statistics that smoking was a major cause of lung cancer and other harms, despite the tobacco industry insisting nothing was proven.
Typical RCTs with only a few hundred patients deliver much less resolution than this result. We do still need trials to home in on the molecular agent, but Tdap is already proven safe, and wise to stay current on, so it would be foolish to "wait and see". If it turns out Tdap (e.g.) protects only some patients from dementia, you are anyway safe from tetanus infection.
It is similar to the case where arginine supplements appear to cut epithelial tissue side effects of SARS-2 vaccines. It needs more study, but arginine is cheap and perfectly safe, so starting immediately to administer arginine supplements alongside vaccination is the prudent course.
Some RCTs even yield spurious results, as a consequence of poor design or execution, such as those lately promoted as showing that anti-depressants have no effect.
Fetishism should have no place in medicine.
Where is my nobel?
https://en.wikipedia.org/wiki/Tetraethyllead https://www.pbs.org/wgbh/nova/article/herbert-needleman/ https://en.wikipedia.org/wiki/Thomas_Midgley_Jr.
Have they studied if air conditioner or fan sounds have a similar effect?
