Missed that, thanks. So between 0.5-1 then probably.
SARS CoV-2 coronavirus / Covid-19 (No tin foil hat silliness please)
- Thread starter Don't Kill Bill
- Start date
Around 4 times as many deaths as Denmark and Norway combined (while having the same population). And likely getting worse.
I'm going to place my bets on red wine & Guinness. Will let you know the results.
This is really good, if true.
fecking hellI didn’t watch the video. Just read the summary. I didn’t come to any conclusion either, just asked a question.
His analysis may well be spot on. From what I’ve seen the data on hydroxychloroquine in covid is generally lacking/a bit crap, so if that’s his conclusion I would agree with it. The data on remdisivir is also lacking/a bit crap, in my opinion.
I have already watched that video and it has several issues:
The experiment they carried out was pretty basic, but interesting and a good start nonetheless. They took images using a laser. They do not appear to carry out any diagnostics to quantify anything meaningful other than how far the droplets reached. The paramaters they need to quantify are droplet size and velocity, surrounding gas velocity, and droplet concentration. Whilst it is very difficult to do these things simultaneously, Particle Image Velocimetry is a well established technique and can be done at different times (i.e. measure the gas conditions and then measure droplet velocity). You can use, amongst others, Phase Doppler or other techniques to measure the size of the droplets too. Phase Doppler also has a limited capacity to measure droplet concentration at a point in space. Not reporting the size or velocity makes the study interesting and a good start, but certainly not conclusive. Similar studies have been carried out for droplets in engineering for decades. The novelty of their work appears to be releasing the droplets specifically from someone sneezing. In engineering it would likely be some spray system, pipe flow etc but the fundamental physics are the same. One condition missing from their experimental study is that the background air is quiescient but in outdoors, you will often have a light breeze at minimum, so you effectively have turbulent motion. Turbulence (or any meaningful laminar flow) is what is really complicating the picture here, not necessarily quiescient conditions.
At 1:30 in the video they say "you can see a large droplet about 1mm in diameter". Well I would disagree. What you see there is just a photo - at best you can say it is a liquid ligament. You can see some droplets, I don't think you can measure accurately the size. You can't say you see droplets of 1mm there unless you've actually measured them. Measuring droplet size with photos is possible with certain conditions, but when you get to microdroplet size and when you also have a large field of view, typically you need to use laser diagnostics such as Phase Doppler or something more sophisticated because the droplets size can't be imaged well due to the diffraction limit. This is an optics issue, something I don't really understand at all, but it is very real and there is I believe something called the Rayleigh criterion to determine it. Maybe some budding photographers will know more about this.
At 1:40 I don't know what they mean by a high sensitivity camera, but okay, it seems to give some useful image data.
2:06/5:53 I've said it several times, water droplets in air are not "light". This is just factually wrong. They are "heavy". "Light" droplets would refer to when the droplet density is smaller than air and I don't believe the droplets here have a lighter density than air because they are "droplets", i.e. liquid. I've already said before, the dynamics of light droplets in air and heavy droplets in air are completely different. I could be wrong, maybe their density is indeed lighter but I doubt it.
2:16 They've previously mentioned that some droplets were 1mm in size, and now they are saying they are just "microdroplets". Which is it? The distinction is important because how the droplets disperse both in still and moving air depends strongly on size. What they really should say is you have a polydispersed cloud of droplets, which means you have a range of different droplet sizes.
3:49 Simulations in multiphase flows are bereft with issues. Without any details given, you should take every simulation with a pinch of salt. For example, does this simulation account for heat transfer processes, e.g. evaporation. Does this simulation use Lagrangian or Eulerian tracking of the droplets (ie. how does it try to "track" the droplets)? What simiplification of the equation of motion of the droplets did they use? Did they study coupling effects/ collisions? Did they use RANS, LES or DNS for the single phase flow? Just a whole lot of questions. Take everything about the simulation with a pinch of salt.
5:03-5:14 Again a factual error and complete nonsense. Even without surrounding air motion, droplets will move due to gravity. Droplets less than 20 micron will also move somewhat due to Brownian motion, and this becomes more pronounced at sizes <1 micron. The reason they remain suspended is because Brownian motion acts in several directions and their terminal velocity (caused by gravity) is extremely small - in other words they fall to the ground very slowly. I know what they are trying to say. They are trying to say that droplets remain suspended within a small confined space for some time, but it could and should be clearer than what they have said. They've also not considered that the droplets may simply evaporate.
5:27 "Opening windows and having air circulation". Just wishy washy words to say that the motion of small droplets becomes correlated with background air motion. This is not new and has been known for decades. Infact, it is exploited by Particle Image Velocimetry to measure gas flow velocity, which I mentioned above. Very high velocity air motion will probably enhance evaporation too.
So to conclude they seemed to ignore or neglect to discuss turbulent motion, which is everywhere when you go outside. They've completely ignored anything to do with evaporation. They've ignored social distancing measures of 2m and the terminology they use is misleading at times. All this video does is create fear amongst people who won't understand the physics which is the vast majority of people. The experiment is a good start, but ideally we need to continue that with more sophisticated experimental conditions and also better laser diagnostics (or other diagnostic) measures. So I don't think that video explains anything to be honest.
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Interesting info - thanks for sharing. One interesting aspect is that the time of the outbreak being in colder season also meant closed windows etc. Could also mean that we better weather coming some of the spread may be impacted.
A lot of the video is rubbish.
Indoors, you still have air motion due to people constantly walking, air conditioning systems, opening/closing doors, extraction systems etc. You can also generate air motion through temperature gradients (natural convection) and I think density gradients as well.
Couldn’t disagree with your take but with better weather at the very least people are less likely to massing indoors. Surely this will be good. Anyway trying to find some positivity.
Oof. Quite the takedown!
This place is great. The range of expertise on here never ceases to amaze.
Now can one of ye please invent a vaccine?!
You’re basically correct. Better weather should reduce spread. That’s one of the theories about why so many viruses are seasonal. We spend more time out and about, less time indoors close to other people. Other theories are about UV light and warmer air temperature breaking down viruses quicker outside the body. And schools being closed.
Seconded. I love the range of informed opinions I can find on the Caf.
Sure, it is from Revelation 6. The rider of the white horse with the crown(Corona) and the bow the ancient Greek word (Toxon) can also mean a biological agent, or a virus. The opening ceremony of the 2012 Olympic games in London actually contains many clues to what is going on. There is a plan behind all of this. Go to youtube and search for "olympic games opening ceremony 2012" and take your pick from the results.
https://edition.cnn.com/2020/04/21/opinions/bergen-osterholm-interview-two-opinion/index.html
Grim but honest read from Michael Osterholm. This guy made a lot of predictions that have since materialized.
Makes a good point that washing your hands will not suffice. If you share the same space as an infected person you increase your chances of getting it.
He also predicts 800,000 dead in America. And even if we find a drug to treat it, that wont stop transmissions.
Grim but honest read from Michael Osterholm. This guy made a lot of predictions that have since materialized.
Makes a good point that washing your hands will not suffice. If you share the same space as an infected person you increase your chances of getting it.
He also predicts 800,000 dead in America. And even if we find a drug to treat it, that wont stop transmissions.
1) "Corona" - yeah, that word's language didn't even exist when Revelation was written. So, your etymology is lacking.
2) Toxon - means bow. Toxin comes from a combination of terms that refers to poison tipped arrows, so again, your etymology is lacking.
3) 2012 Olympic "plan" details are... [shrugs shoulders]. Don't tell someone to go on some Youtube scavenger hunt. You're the one bringing it up, you give the evidence.
Basically, all I see here is a shit attempt by you at explaining your confirmation bias.
Ecuador suddenly 10977 cases and 1028 deaths reported just now. As I mentioned earlier there has been thousand of deaths propably due to covid-19 there in march/april, but I guess they now have got more testing capabilities.
Assuming the 0.5% is true, it is more. There are more deaths than reported and there is also a lag between infections and deaths. 30-40 could be a decent estimate for cases two weeks ago or so. Or is it three, unsure what the average lag between infection and death is.
Shouldn't you be out and about, protesting in America.
You sound like my boring ass 1D gasdynamics professor
And yet when I asked you about "fecking droplets, how do they work?" you said nothing
Probably far too stoned.
This whole social media driven conspiracy bollox about how we can’t trust “MSM” is really taking hold. Which is a disaster because - although the mainstream press has its flaws - the alternative is infinitely worse.
Unless that survey was done in America? In which case, fair enough. Fox news etc
*clap*
I have said from the beginning of all this, it's the idiots that will kill us all, not covid-19.
So everyone around me just started clapping and letting off fireworks........................it's been a tory stronghold for decades.
The clap makes you proud to be British. Very classy.
Well done NHS.
Well done NHS.
I keep saying that to my ex but she still won't unblock me
The papers have come up with lots of conflicting and contradictory stories, much (but not all) of it for shock value and to boost sales.
They may well be relaying accurate news based on a selection of experts. But that doesn't mean that readers are going to be happy about it.
Media companies tend to sell themselves based on defined narratives. Fox has its narrative, the Guardian has its, the Telegraph has one too. Each of viewerships/readerships want their opinions reinforced and their favourite narratives told over and over in slightly different ways. That's why they choose the media they do.
What these viewerships/readerships don't particularly want is changes or twists in the overarching story. The latter is what's been happening. It's the opposite of confirmation bias, and people are unhappy about their favourite outlets constantly shifting the sand under their feet. A range of opinions might be better for everyone's understanding, but it's not what leads to trust. Which is unfortunate.
They may well be relaying accurate news based on a selection of experts. But that doesn't mean that readers are going to be happy about it.
Media companies tend to sell themselves based on defined narratives. Fox has its narrative, the Guardian has its, the Telegraph has one too. Each of viewerships/readerships want their opinions reinforced and their favourite narratives told over and over in slightly different ways. That's why they choose the media they do.
What these viewerships/readerships don't particularly want is changes or twists in the overarching story. The latter is what's been happening. It's the opposite of confirmation bias, and people are unhappy about their favourite outlets constantly shifting the sand under their feet. A range of opinions might be better for everyone's understanding, but it's not what leads to trust. Which is unfortunate.
It's their own fault.
They're all so desperate to be relevant and get clicks that they're taking any expert's word they can find as gospel, without acknowledging that the experts are learning about this virus too and are being proven wrong all the time as we understand more about it.
no flights
Expect an announcement tomorrow from the Welsh Government on loosening the lockdown restrictions. England won't be far behind.
Really? That goes against everything they have said so far - they were at great pains to say they would extend further than England if need be.
Maybe they were just making the point that they will do their own thing. Far less deaths in Wales, so it makes sense.
Uh oh, someone pulled Im red2’s cord again.
So is it 14% or 21%.