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March 7

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There is a claim of a Eucharistic miracle at Sokółka, Poland where upon close scientific examination, cardiac muscle fibres of a dying man were found intermixed with bread fibres in a way that no one can reproduce. Furthermore, there is another purported miracle I find somewhat compelling (which we do not have an article on), Our Lady of Las Lajas, Colombia. [1] Has the latter case been examined scientifically? Are there any skeptical scientists who have examined the first purported miracle? Why have neither of these claims been nominated for the Randi Prize? 2607:FEA8:1DDF:FEE1:C0AC:BED:E678:E3B (talk) 01:56, 7 March 2020 (UTC)[reply]

The Randi prize would require that this was reproducible, ie wafer turned into bread and heart mixture in a laboratory. I assume these were one off events with no careful checking beforehand. Graeme Bartlett (talk) 12:30, 7 March 2020 (UTC)[reply]
Also it's been discontinued according to the article. --47.146.63.87 (talk) 05:56, 8 March 2020 (UTC)[reply]
"X is not supernatural" is an unfalsifiable hypothesis. I'm idly curious as to how the scientists mentioned determined that the "interleaving" was "not reproducible". How would they tell if it was? Did they publish anything about this in a peer-reviewed journal? Also I'll note with a bit of amusement that the Catholic Church is usually very adamant that transubstantiation is not cannibalism, but there's no concern here. What if someone hadn't noticed and tried to consume it? (Assuming it's purportedly human tissue, which wasn't addressed, but I guess God turning something into a rat's heart wouldn't be as impressive.) Or I guess if God did it that means it's okay? --47.146.63.87 (talk) 05:56, 8 March 2020 (UTC)[reply]
I hope no human sacrifices are being conducted in the church of Saint Anthony in Sokółka, but from a forensic perspective I think the fact that the floor from which the Blessed Sacrament was picked up has not been immediately examined means that all bets are off. The article has been published as: Zbigniew Jacyna-Onyszkiewicz; Maria Elżbieta Sobaniec-Łotowska; Stanisław Tadeusz Sulkowski; Andrzej Kakareko; Mirosław Rucki (2018). "Eucharystyczne trwanie z perspektywy nauk ścisłych" [Eucharistic persistence from the perspective of the exact sciences]. Teologia i Człowiek (in Polish). 43 (3): 81–98. doi:10.12775/TiCz.2018.028. The full text is accessible on-line.  --Lambiam 18:00, 8 March 2020 (UTC)[reply]

Sex differences in death rates for the Wuhan coronavirus

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I've heard that men are more likely to die from the Wuhan coronavirus than women. Is it true that men are more likely to die of it than women, and if it is, what explains this? Freeknowledgecreator (talk) 05:47, 7 March 2020 (UTC)[reply]

Possibly due to more smoking. Graeme Bartlett (talk) 12:30, 7 March 2020 (UTC)[reply]
'On the question of why the virus is attacking men more than women, research has shown that, in China, many more men smoke than women. In fact, more than half of Chinese men smoke, compared with only around 3% of women. Smoking activates a receptor used by the coronavirus to infect human cells, ACE-2, Dr Greg Poland, a vaccine researcher and infectious disease specialist with the Mayo Clinic, in Rochester, Minnesota said, although this is speculative at this stage. However, Preiser weighed in and explained that if someone's lungs are affected by smoking (in a way, a chronic illness), then that certainly increases the risk from a virus that affects the lungs as “one has 'fewer reserves' to fall back on when the lungs are infected and inflamed”, he said.
Dheda adds: "Smokers are at higher risk of contracting many respiratory tract infections including influenza, TB, and Streptococcus pneumoniae, an important cause of acute pneumonia. There are a number of mechanisms by which cigarette smoking does this, including subverting the defensive functions of the airway lining and various types of immune defensive cells including macrophages and lymphocytes."' [2] Alansplodge (talk) 12:37, 7 March 2020 (UTC)[reply]
OK. So, if the difference is due to men smoking more, presumably there is no evidence that men are inherently more vulnerable to the disease? Freeknowledgecreator (talk) 00:32, 8 March 2020 (UTC)[reply]
It's too early to say for sure. As the disease spreads, more populations can be studied and the picture may become clearer. And, as always, "Absence of evidence is not evidence of absence." Matt Deres (talk) 02:09, 8 March 2020 (UTC)[reply]
If the difference is due to men smoking more, then the difference is probably simply due to smoking. Perhaps more attention to this factor needs to appear in sections about who is most likely to suffer serious consequences from this virus. HiLo48 (talk) 02:30, 8 March 2020 (UTC)[reply]
We need studies to say for sure. This is a hypothesis at present. --47.146.63.87 (talk) 06:10, 8 March 2020 (UTC)[reply]
That would be angiotensin converting enzyme 2. --47.146.63.87 (talk) 06:10, 8 March 2020 (UTC)[reply]

According to this article, there are differences between the immune systems of men and women that may partially explain the different death rates from the virus. So it's not necessarily just smoking. Freeknowledgecreator (talk) 09:10, 8 March 2020 (UTC)[reply]

Carbon monoxide questions.

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How is CO excreted by the body? If it is at all. Carboxyhemoglobin eventually goes to the liver right, so isn't it eventually urinated out? As with red blood cells? 2ndly, what % of CO we breathe in is excreted out, because I heard someone say a % generally stays in your body for good. But that % is prolly just stuck in the liver, making it harmless? So maybe a % of it is released within years? And the rest urinated out? Thanks. 67.175.224.138 (talk) 14:32, 7 March 2020 (UTC).[reply]

It is my understanding that the CO remains tightly attached to the carboxyhemoglobin, even until the latter is removed from the blood by the kidneys. The main reason CO has such an adverse effect is that it cancels some haemoglobin, molecule for molecule, and that molecule of haemoglobin is never resuscitated. Dolphin (t) 03:40, 8 March 2020 (UTC)[reply]
No, CO isn't an irreversible inhibitor. See carboxyhemoglobin. The problem is that CO has a much greater affinity for hemoglobin than oxygen, so oxygen at ordinary concentrations doesn't displace CO quickly. --47.146.63.87 (talk) 06:28, 8 March 2020 (UTC)[reply]
So if CO unbinds to hemoglobin, it'll just rebind to another hemoglobin, and so and so forth, until it unbinds and there are no more hemoglobin binded to a CO or O2 left. Then it just continues down the blood vessel until? Until urinated out? 67.175.224.138 (talk) 04:03, 9 March 2020 (UTC).[reply]
"exhaled". When it's dissociated, it can diffuse back out in the alveoli (reversible transfer in/out at lungs. One basis for hyperbaric oxygen therapy is that the overwhelming amount of O2 being inhaled more rapidly exchanges for the O2 (doi: 10.1126/science.111.2894.652 is an early study on that). DMacks (talk) 05:26, 9 March 2020 (UTC)[reply]
Yes, carbon monoxide-releasing molecules discusses this some more, with some information that probably should be moved to the main CO article. Note that it can diffuse out of the blood into tissue as well. This happens normally, as some CO is produced in the body (endogenously), so it's always present. CO only becomes "bad" when your inhale enough of it to interfere with oxygen transport. An essential thing to understand in biochemistry: the dose makes the poison. --47.146.63.87 (talk) 20:25, 9 March 2020 (UTC)[reply]
Red blood cell § Life cycle: red blood cells have a lifetime of about 4 months in the blood, after which they're broken down. But as I noted above, CO doesn't stay bound forever. The problem is while it is bound, the hemoglobin can't carry oxygen, and meanwhile your cells need oxygen, so if enough hemoglobin gets "poisoned" by CO you start suffering hypoxia. Cool fact: your body produces some CO itself as a signaling molecule. --47.146.63.87 (talk) 06:28, 8 March 2020 (UTC)[reply]
Also worth a read: Heme oxygenase. CO is produced in the metabolism of heme from hemoglobin and other proteins by heme oxygenase which is itself a heme enzyme. This is quite complicated. Pelirojopajaro (talk) 15:55, 10 March 2020 (UTC)[reply]

A wasp on a boat

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So I was on the open-air deck of a ferry this weekend and there was a wasp buzzing round my head for quite a few minutes. Not on me (or on anything) but flying round like they do. Which got me wondering... to manage that, does a wasp have to fly really fast? Because the boat's moving at some speed, and if the wasp isn't resting on the boat or something on it, surely to keep pace it has to be circling at the same speed? Amisom (talk) 18:36, 7 March 2020 (UTC)[reply]

It would have to be flying fast to the same degree that you were experiencing any wind caused by the ferry's motion.
Consider that if you are inside an airliner travelling at 500mph, and walk forward at 5mph, then you are walking at 505mph relative to the ground, but you are not having to expend any unsual energy. On an open ferry, the superstructure is dragging some air along with it, so at, say, 20 knots (23mph) neither you not the wasp are likely moving through the local air at that speed. Moreover, that disturbed air will have turbulance and eddies, and insects that have been honing their flying abilities for more than 150 million years are probably very good at sensing and exploiting air currents to their advantage.
All that aside, according to this a common type of wasp can fly (through the air) at up to 30mph. {The poster formerly known as 87.81.230.195} 90.202.210.25 (talk) 21:02, 7 March 2020 (UTC)[reply]
The scenario reminds me of the old joke about a guy transporting birds in a truck, and is over the weight limit, so he keeps banging on the wall of the truck, to startle them and keep them flying. ←Baseball Bugs What's up, Doc? carrots23:35, 7 March 2020 (UTC)[reply]
You're standing on Earth, which is rotating at about 1,000 miles per hour. That translates to about a quarter mile per second. Yet, if you jump up in the air for a second, the ground does not move a quarter mile under you. ←Baseball Bugs What's up, Doc? carrots23:38, 7 March 2020 (UTC)[reply]
That's not really the same physics: in the case of the wasp, the relative airspeed depends on how much the air in the slipstream around the boat is co-moving with the boat, which is a question of complicated fluid dynamics and friction; and in the case of the Earth rotating, that's a scenario that is mostly defined by inertia and conservation of angular momentum; and although we can draw some parallels, it's misleading to say that they're well-described by the same physical model. Of course, the laws of physics are the same in both cases, but the dominant effect is different. Nimur (talk) 15:00, 10 March 2020 (UTC)[reply]
Sure. And if you jump up, and there's a strong wind gust, you might well not land precisely where you began your jump. Although you wouldn't be a quarter mile away unless maybe a tornado came along around then. Obviously, a small insect is going to be impacted by the wind quite a bit more than we would be. ←Baseball Bugs What's up, Doc? carrots16:28, 10 March 2020 (UTC)[reply]