exchemist
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Here are the relevant stats for England and Wales (most of the UK): https://www.statista.com/statistics/1402232/england-and-wales-firearm-homicides/ The incidence of firearm homicides is pretty stable, at around 30/yr. If you add in a few more for Scotland and N Ireland you might get to 40. Presumably that it is the gun culture in the USA that makes these shootings such a regular and apparently accepted feature of American life.
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I MAY WIN A NOBEL FOR THIS: I've proved racial inequality!
exchemist replied to NobelPrizeLaureate's topic in Trash Can
The population of the USA is 335m, not 100m. Can you provide a reference to this GAD ranking system? -
Yes of course money continues to be spent on covid countermeasures. I very much doubt if billions of public money is being spent on them in the USA. But drug companies will be sending a fair bit I expect, in the expectation that many countries' health systems will continue to need a pipeline of antivirals for a long time to come.
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Sure. So in other words, we have now reverted to ânormalâ after the pandemic and no longer feel the need to divert huge sums of public money into crash development programmes, trials and so forth. From the article, I gained the impression that further antivirals can be expected in due time, no doubt stimulated by the emergence of the drug resistance referred to.
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Because, as I say, we are not any longer in the middle of a global health emergency involving a largely unknown virus. We have a largely vaccinated population, our medical services are under a lot less pressure and we know a great deal more about the virus. So we can take our time and try to get better antivirals more deliberately than we could in the initial rush to get something out that worked.
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In case you have not seen it, I thought this was rather good, for a bit of much needed light relief:
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Does it? I read it, admittedly rather quickly, as explaining the issue of resistance and the limitations of any antiviral approach. That applies to the first antivirals just as much as subsequent ones. That is what the article, not I, seems to be saying. I most certainly did not say 2nd generation antivirals are harder to make than 1st generation ones.
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Is the text highlighted in blue your own words or are you quoting someone else, and if so what is the source? I'm not sure it is strange. There may well be work on further antivirals but such work, now that there is no longer a global health emergency, would not be expected to result in regular updates in Wikipedia. I had a quick look on the web and found this review from Jan 2023 : https://pharmaceutical-journal.com/article/feature/next-generation-antivirals-targeting-covid-19. which explains the challenges and refers to next generation antiviral approaches. So it's clear that a fair amount of research was in progress at that time. What has happened since I do not know. But don't forget that antivirals are not vaccines. The mainstay of the public health approach to covid remains vaccination. Antivirals are only a last resort, used to help the immunocompromised or others that become very ill for some reason.
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The thickness of a metal sheet will very likely make a big difference. A thick sheet will warp less easily, I suspect. It will have greater mechanical strength and the thicker material may be able to conduct heat away better and so reduce peak local temperatures. But not sure we can be of much more help. You've got onto the coefficient of thermal expansion, which is must be the key point of science involved in this application. Sounds to me as if you were very nearly there with the glass, if it lasted 8 months. But obviously not quite. Pity.
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You've been given some reasons by other respondents. Also, it takes a lot of research to establish a safe level. The mere statement that this has not been done does not in any way imply that trace levels are actually significantly harmful. You can flip it around and say with equal justification that there is "no evidence" trace level are harmful.
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Ah, now your last idea could have something to it. There you certainly do want to convert a slow oscillating motion into a faster rotary motion.
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Good point, conservation of angular momentum also rules out a free electron absorbing a photon. s= 1/2 and thatâs all it can ever be, whereas a photon has 1 unit that has to go somewhere. In a bound state the electron may be able to acquire other types of angular momentum apart from its intrinsic spin, e.g. orbital angular momentum in an atom or molecule.
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I thought there was also another reason: you need a transition dipole moment, which a free electron cannot provide on its own. But thatâs just what I have understood from quantum chemistry.
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It seems to me the first issue you would have to address would be how to deal with the point made by @OldTony that, if it were a trunk piston engine, there would need to be a slot cut in the side of any cylinder, to accommodate the motion of "connecting rod 2" in your diagram. Clearly that can't work, so a trunk piston design is ruled out. I presume you could deal with that by a crosshead type of design in which, say, a pair of opposed cylinders is joined by a horizontally moving piston rod, connected by "slider 2" acting as a crosshead. But that will take up quite a lot of space. Have you given any thought to this issue? Maybe it could work in a marine engine, where space is not a critical issue. One advantage of it could be the long throw of the pistons, compared to the crank, which could give a long expansion for each power stroke, giving greater efficiency. Marine crosshead engines can have stroke:bore ratios up to 4 for this very reason. But then, in marine applications the propeller speed is generally low compared to IC engine rpm, so something that doubles the rpm is not what you want. On reflection I think I could perhaps more easily see your idea working in reverse as a pump, in which the crank drives the pistons. What I struggle to see is how this can give a "fast" engine. With IC engines the challenge is usually to bring the speed down, from the high speeds needed for combustion to the speeds needed for motive power. The exception is marine engines burning residual fuel oil, which can work with engine speeds as low as 75-100rpm, at which speed they are directly coupled to the propeller, avoiding the need for a gearbox that can handle outputs that can be in excess of 40MW. But then you don't want to double the speed of the output shaft.
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No, I meant contamination of the planet by micro-organisms from Earth, i.e. we should not introduce contamination to the planet.
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Avoidance of contamination. We would go to great lengths to investigate it by means of carefully sterilised probes (unmanned of course).
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I read that in the FT, which wryly commented that Bezos had a meeting with Trump the day the non-endorsement was announced. These oligarchs are falling into line behind Trump, one by one. When the chips are down, what counts for them is the prospects for their business and their personal fortunes. After all, democracy is for the little people. Peter Thiel has a survival bolthole in New Zealand if things get too hot in the States, having taken out NZ citizenship as a precaution. And Musk is trying to buy votes, on Trumpâs behalf. These individuals are out of control.
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So nothing like a ton, then. But lucky you. It's fairly non-toxic and melts in the hand (at 30C) which is rather fun. It is also one of the very few material that expands on freezing, like water. So a rather splendid curiosity. Seems very odd it has been left behind though. What kind of lab was this, do you know?
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Even for gamma rays that wonât achieve anything. Two sets of waves encountering one another at an angle will just pass through each other and emerge on the other side unchanged.
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The laws of nature donât impose any limit on the viability of electric vehicles. IC engines have managed to serve us quite well, in spite of the severe limitations on their efficiency imposed by the 2nd law of thermodynamics on heat engines, a limitation EVs do not suffer from. There is no reason to think that EVs cannot compete - as is clearly shown by the sales statistics I quoted previously.
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What I do remember is the story of the teacher saying that, while two negatives make a positive, two positives still make a positive. To which a voice at the back of the class remarked: "Yeah. Right".
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One of the most pointless phrases to learn in another language
exchemist replied to Janus's topic in The Lounge
I only know one word of Finnish, which is hissi, for a lift. I used to go regularly to Vaasa, to visit WÀrtsilÀ, who make a lot of the world's big marine and powergen diesels and for some reason that word stuck in my mind from the hotel I used to stay in.