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September 17

Teach flight tricks to parrot?

Is it possible to teach a parrot (goffin) to do loops and barrel rolls in flight? Or things like flying upside down or backwards? Can't find much online. Thanks. 146.200.128.134 (talk) 04:22, 17 September 2020 (UTC)[reply]

Despite their intelligence, goffins are not built for acrobatics, and I doubt whether any bird would be able to fly upside down or backwards.--Shantavira|^{feed me} 08:57, 17 September 2020 (UTC)[reply]

Hummingbirds can fly backwards and upsidedown. --TrogWoolley (talk) 09:32, 17 September 2020 (UTC)[reply]

I've seen Hummingbirds vanish into thin air, then reappear a moment later 30 metres away. Amazing birds. Try typing 'do a barrel roll' into your parrot, might work. Zindor (talk) 11:26, 17 September 2020 (UTC)[reply]

Seagulls can fly (or glide) backwards. 146.200.128.134 (talk) 17:13, 17 September 2020 (UTC)[reply]

But can they do it in high heels? —Tamfang (talk) 01:59, 18 September 2020 (UTC)[reply]

With enough practice, seagulls can teleport. Mitch Ames (talk) 08:16, 19 September 2020 (UTC)[reply]

Generally teaching tricks to an animal that doesn't have a trained animal to imitate involves immediately rewarding any random behaviours that are close to what you want (either by showing praise/affection if the animal is used to that or by food treats). Then you carry on rewarding that behaviour every time it happens, combined with giving a signal (hand gesture, whistle, voice command, etc). This can take a long time, but eventually you will be able to give the signal first and the animal will respond with the "trick". With training chimpanzees and gorillas, you would usually give a signal first to say "now we are starting work", then after the training session is ended, another signal to say "now we can play". This takes a lot of patience, and you have to be very careful not to wear the animal out by endlessly repeating signals, initially you should only use them when you think the animal is going to respond correctly. There's no reason why you can't train a parrot to do flight tricks if it's something they can normally do. Good luck.49.197.49.86 (talk) 23:32, 19 September 2020 (UTC)[reply]

There is a reason you can't train an elephant to take a leap through a sequence of hoops, or a dolphin to skip rope, which is not for lack of intelligence or insensitivity to rewards. If you know otherwise, you can earn a fortune by training your cat to give a recognizable performance (it does not have to be pitch purrfect) of the Moonlight Sonata. --Lambiam 09:39, 20 September 2020 (UTC)[reply]

September 18

Energy from rusting

Roughly speaking how much energy, in Joules, is given off by completely rusting 1Kg of Iron? 2A01:E34:EF5E:4640:6149:84E9:11CE:A892 (talk) 09:47, 18 September 2020 (UTC)[reply]

The article on energy density has a handy table. Rust can have different compositions, but the "burned to iron(iii) oxide" row should be a decent enough approximation. 85.76.15.6 (talk) 10:52, 18 September 2020 (UTC)[reply]

Why are Pnictogen hydrides so poisonous?

Why are Pnictogen hydrides like ammonia,phosphine and arsine so poisonous?Acidic Carbon (Corrode) 13:23, 18 September 2020 (UTC)[reply]

Should there be a redirect: Pnictogen hydrides → Pnictogen hydride ? --2606:A000:1126:28D:31A8:66E0:89AA:D98E (talk) 16:48, 18 September 2020 (UTC)[reply]

Each one's article talks about its specific toxicity profile. At least phosphine#Toxicity, arsine#Toxicology, and stibine#Toxicology are quite explicit about what their mode of action is. DMacks (talk) 17:05, 18 September 2020 (UTC)[reply]

Ammonia is not so dangerous as the others. Its main issue is as a strong base. Animals have a way to deal with ammonia in the body. For humans it is to make urea. Graeme Bartlett (talk) 22:28, 19 September 2020 (UTC)[reply]

Missing a hurricane

Hurricane Alice (December 1954) says that two cyclones, including a Category 2 hurricane, operationally went undetected in 1954. In a time before satellite pictures, how would meteorologists learn that they hadn't noticed a storm? 2601:5C6:8081:35C0:2C6E:461:D260:3BF (talk) 22:26, 18 September 2020 (UTC)[reply]

No source is cited for that specific statement, but José A. Colón's paper cited as a reference from the paragraph refers to another undetected hurricane in January 1951. Basically the answer to "how did they learn" seems to be that they reanalyzed the data they had already collected, when the storms were over with and they had time to do it. --174.88.168.23 (talk) 23:08, 18 September 2020 (UTC)[reply]

September 19

Medications causing dizziness and loss of balance

I am a retired psychiatrist and a friend of mine who is an audiologist asked me to write a chapter for his upcoming book about some stuff audiologists do. It turns out they do balance in addition to fitting hearing aids, so their clients are mostly elderly. He is most interested in medications that might affect man's balance, cause dizziness, etc. Also the medications he is interested in are those which he might see to have been prescribed to his clients because he needs to differentiate between organicity and medications side effects. I have written already most of the psych stuff: antipsychotics, antidepressants, antiepileptics, opioids, etc and wonder if someone can give me pointers to other areas which I possibly missed. Thank you AboutFace 22 (talk) 15:15, 19 September 2020 (UTC)[reply]

There is a list here: "Medications causing Loss of balance". www.rightdiagnosis.com.

Which links to: "Conditions listing symptom: Loss of balance - View All". www.rightdiagnosis.com.

Further, related to audiology: "Acoustic neuroma Symptoms, Diagnosis, Treatments and Causes". www.rightdiagnosis.com.

107.15.157.44 (talk) 15:58, 19 September 2020 (UTC)[reply]

Medication that makes one dizzy makes it unsafe to drive or operate heavy machinery. I think the converse also holds rather generally: medication that makes it unsafe to drive or operate heavy machinery can cause dizziness. You might want to check medication that is thus labelled (like those on this list) and that is not already on the other list(s). --Lambiam 18:41, 19 September 2020 (UTC)[reply]

Browsing this site, which generally includes references, may provides some ideas: medications associated with dizziness, ototoxic medications, drug treatment of vertigo (list of vestibular suppressants), neurotransmitters in the vestibular system. Affect man's balance, cause dizziness, etc. seems like a pretty broad scope. fiveby(zero) 18:55, 19 September 2020 (UTC)[reply]

Thank you very much! It is a GOLD MINE! AboutFace 22 (talk) 19:47, 19 September 2020 (UTC)[reply]

Shouldn't an audiologist already be cognizant of these things? ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:48, 19 September 2020 (UTC)[reply]

Our writer is a psychiatrist though! Better check out the audiologist page for knowledge and skills required. (our article does not mention drugs, and is only two subsctions). Graeme Bartlett (talk) 22:25, 19 September 2020 (UTC)[reply]

Yes. But shouldn't a trained audiologist already know this stuff? If he does, why does he want someone else to write about it? If he doesn't, how did he ever get to be an audiologist? ←Baseball Bugs ^{What's up, Doc?} carrots→ 22:55, 19 September 2020 (UTC)[reply]

Don't be mean, B B. Audiologists don't get trained in drugs. To get versed in drugs you have to go through a lot of chemistry, biochemistry, physiology, etc. It is the stuff of either a medical or veterinary school. AboutFace 22 (talk) 00:24, 20 September 2020 (UTC)[reply]

Probably beyond any but specialists to keep up to date. Here's a survey of pharmacology for just the vestibular system. Amazed that homeostasis can keep such an ill-designed system as the human upright and functioning. fiveby(zero) 12:07, 20 September 2020 (UTC)[reply]

Bugs, audiologists don't deal with medications very much. You may be thinking of otologists (ear doctors). AboutFace 22, it might be of some interest that psychiatric meds (particularly escitalopram) are sometimes used to treat balance disorders. I don't know the reason for this but there is apparently an explanation that makes some sense. 2602:24A:DE47:BB20:50DE:F402:42A6:A17D (talk) 04:52, 20 September 2020 (UTC)[reply]

Examining a person's balance does not require much training. In some contexts it may be relevant to know if that balance may have been affected by the (possibly temporary) use of medication. A thorough handbook dealing (among several topics) with the topic of balance examination could do well by listing which medications are known to affect equilibrioception and therefore have a possible effect on a person's balance. --Lambiam 09:33, 20 September 2020 (UTC)[reply]

The link between audiologists and people who don't have balance disorders is this:

Someone with hearing loss may be asked to listen to sounds of varying pitch and intensity to establish where the deficiency is. Then water is irrigated into the ear canals. If there is impediment to its movement that may indicate a diagnosis of canal paresis (the degree of it is expressed as a percentage). If the water fills the canals the patient will experience balance disorder (vertigo) until it drains. 82.15.199.219 (talk) 13:33, 20 September 2020 (UTC)[reply]

Safe displays of highly radioactive isotopes

Suppose you had a museum of the elements, with a kg sample of each stable element (in an inert atmosphere if needed). What could you do for Tc, Pm and the actinides?

For example, you might want a kg of plutonium-238 oxide, or enough to glow orange hot (as in our picture at Pu-238), to illustrate its use as a power source in space probes. It decays by alpha radiation, so the glass of the display case would be all you'd need for shielding. But the decay products decay by beta radiation, which means the shielding could produce bremsstrahlung gamma radiation. That might not be significant for Pu-244 (assuming it were possible to synthesize a kg of Pu-244), but would be for Pu-238.

(I can't find how much spontaneous fission there would be, and if it would be dangerous in such a display. Some sources give alpha radiation as the only decay mode of Pu-238, some give alpha and fission.)

Also, why isn't the beta/bremsstrahlung radiation and SF damaging to radioisotope thermoelectric generators? — kwami (talk) 21:47, 19 September 2020 (UTC)[reply]

A kg sounds like a lot. I once saw a piece of radium displayed in a museum in Leiden, but that was only a few grammes. It was brought there by Marie Curie herself (in a suitcase on a regular passenger train) to have it investigated in Heike Kamerlingh Onnes' cold temperature lab (conclusion: radioactivity is not affected by liquid helium temperatures). The sample was on a 2-month temporary exhibition in a metal box, lined with lead, with a small window of lead glass. There was a fence to keep visitors 2 metres away, warning signs and a radiation counter. If it were on permanent display, there would be a risk that the guides could exceed their legal maximum radiation dose (yes, I checked the numbers). I've also seen radioactive samples on display where the visitor couldn't view the sample directly, but only in a mirror.

Radiation is damaging to RTGs. The half life time of an RTG is shorter than the half life time of the radioisotope inside. PiusImpavidus (talk) 09:30, 20 September 2020 (UTC)[reply]

Good to know, re. RTGs. And a mirror is a nice idea (would the aluminum finish degrade over time?), though it would be fun if you could put your hard against the glass and feel the heat radiating of a plug of PO2, not just see it glow. — kwami (talk) 07:21, 21 September 2020 (UTC)[reply]

You may wish to use Plutonium-244 with a much longer half life. But for many other actinides there is no way you could get a kilogram, let alone display it. Graeme Bartlett (talk) 10:08, 20 September 2020 (UTC)[reply]

I'm not sure we could get a kg of Pu-244 either -- it's supposed to be quite difficult to synthesize. But this is more an fantasy of, if we had a nuclear transmogrifier that could produce any amount we wanted of any isotope we wanted, which ones would be practical for safe display? — kwami (talk) 07:21, 21 September 2020 (UTC)[reply]

xkcd what-if has a humorous take on what would happen if you tried to collect all the elements. At this moment the what-if web server is down, but if you search the web for xkcd "Periodic Wall of Elements" you should find copies. The piece has sage advice such as "The periodic table of the elements has seven rows. [...] Do not build the seventh row." 85.76.39.125 (talk) 05:59, 21 September 2020 (UTC)[reply]

Well, yes, but OP is definitely aware (see below) that you can't display every element. And since the problems xkcd points out for the last two rows are thanks to things like astatine and tennessine, it seems to be a fair question to ask how many radioactive elements you can display before you have a big problem. Certainly the answer is nonzero because of bismuth which is only radioactive on a technicality; the more interesting question is how much greater than zero it is. Double sharp (talk) 12:06, 21 September 2020 (UTC)[reply]

I'm aware that for many elements, even the most stable isotope would be too actinic for safe display, perhaps even if it lasted long enough to put on permanent display. I figured that several would be practical, but how can I know which? It's not just halflife, but decay pathways and the halflives and decay pathways of the products that would need to be considered, and perhaps even the energy of the beta rays, which for all I know differ between isotopes. I'm wondering where I could find out what the radiation hazard would be for various isotopes, and how that would change over years to decades. — kwami (talk) 07:21, 21 September 2020 (UTC)[reply]

For actinides, daughter decay products would build up, some also giving off gamma rays. Graeme Bartlett (talk) 07:43, 21 September 2020 (UTC)[reply]

Some of the main decay chains are just alpha and beta decay, though. So it's a matter of what is needed to block the beta radiation and secondary gamma radiation. I just don't know where to find the specifics. — kwami (talk) 09:40, 21 September 2020 (UTC)[reply]

What, no one has mentioned Theo Gray and his IgNobel-winning Periodic Table Table? I half-remember seeing on his personal website some discussion of displaying the difficult elements. —Tamfang (talk) 01:55, 22 September 2020 (UTC)[reply]

September 20

Three step viper

What sort of snake was the one that American soldiers in Vietnam called the "three step viper"? Supposedly if bitten you'd make it three steps before either dying or being incapacitated.

Apparently in reality it was more like "you'd make 100 steps before you started begging for someone to shoot you", but the name stuck. According to a book I read. 146.200.128.134 (talk) 03:23, 20 September 2020 (UTC)[reply]

Maybe there was no particular snake that people called by that name and they just used it as a nickname for a strongly venomous snake. I did a simple Google phrase search for "three step viper". I found this question, similar anecdotes from Vietnam, a work of fiction apparently set in China, and a site where someone says the phrase refers to the fer-de-lance, which is not found in Vietnam. Nothing that says it refers to a particular real snake. --174.89.48.182 (talk) 06:23, 20 September 2020 (UTC)[reply]

It seems it was a more optimistic name for what others called the "two-step snake", which could refer to the many-banded krait or the green bamboo viper,^[1] both of which are extremely venomenous snakes found in Vietnam. --Lambiam 09:20, 20 September 2020 (UTC)[reply]

You are yet too optimistic: Bamboo Viper (Step-and-a-Half Snake) Extremely posionous greenish/yellow snake that called Vietnam home. The venom contained a powerful nerve toxin. Called a step-and-a-half by U.S. troops because that's about how far you got after being bitten before your terribly painful, agonized death began. Clark, Gregory R. (1990). Bamboo Viper. p. 46. {{cite encyclopedia}}: |work= ignored (help) Others highly poisonous snakes mentioned are Asiatic cobra, Malayan krait, Russell's viper, Malayan pit viper, hook-nosed sea snake, Hardwick's sea snake, brown krait, banded krait and paradise flying snake. fiveby(zero) 12:58, 20 September 2020 (UTC)[reply]

Probably Trimeresurus popeiorum and not the Chinese green tree viper Trimeresurus stejnegeri. Toxicity and identification of Trimeresurus seems pretty complicated, the article says they are primarily hemotoxic rather than neurotoxic. Lambian's link says there were few actual bites, so the name might not be much related to actual toxicity. fiveby(zero) 13:06, 20 September 2020 (UTC)[reply]

@Fiveby: I know little about Trimeresurus but I'd note our article on T. popeiorum says Northern and northeastern India (Mizoram), Burma, Thailand, West Malaysia and Vietnam. In Indonesia, it occurs on the islands of Sumatra, Mentawai Islands (Siberut, Sipora, North Pagai) and Borneo. The type locality, designated by lectotype, is listed as "Khasi Hills, Assam" (India).[2] Gumprecht et al. (2004) consider records for Bangladesh, Cambodia and Vietnam to be highly questionable, as they are likely based on misidentifications involving other species of Trimeresurus.[5] whereas I don't see any mention of a dispute of T. stejnegeri occurring in Vietnam in our article. True that it's claimed T. popeiorum is neurotoxic but T. stejnegeri is hemotoxic (and there seems to be dispute whether these even all belong in Trimeresusrus although I guess that's neither here nor there) but I'm not sure we can be certain from this story that it was neurotoxic. Nil Einne (talk) 21:00, 21 September 2020 (UTC)[reply]

BTW Many-banded krait claims the two-step snake was that with a source, but the source doesn't seem good enough to suggest Lambian's one is wrong. Frankly I wonder whether there was actually a specific snake tied to the legend or whether it's more likely different bites from different snakes all combined. Nil Einne (talk) 21:13, 21 September 2020 (UTC)[reply]

There are stories from the area of children playing with kraits, with none of the elders in the village even realizing they're poisonous despite the fact that the mortality rate is supposedly 50% with antivenom, as they're so docile that no-one's been bitten in living memory. Begging to be put out of your misery sounds more like a viper, but though viper bites tend to be nasty due to necrosis, few vipers are as deadly as the stories that people tell. And since kraits would likely only bite if stepped on, and US soldiers wore boots, we're probably talking about an aggressively defensive climbing snake that might bite your hand as you're pushing through foliage, again suggesting a viper like Trimeresurus. Our unreferenced claim at Trimeresurus_stejnegeri#Venom sounds like it would be excruciating within a few steps. — kwami (talk) 07:33, 21 September 2020 (UTC)[reply]

surgery before antibiotics, and appendicitis in infants

WP's biographical article about Simone Weil (born in 1909) mentions:

Weil was a healthy baby for her first six months, but then suffered a severe attack of appendicitis; thereafter, she struggled with poor health throughout her life.

How would they have treated this issue in those days, and what about now? If they didn't do an appendectomy, would the appendicitis be likely to recur? I have the impression that appendix rupture was almost always fatal in the pre-antibiotic era, and is a serious condition even now. Thanks. 2602:24A:DE47:BB20:50DE:F402:42A6:A17D (talk) 05:02, 20 September 2020 (UTC)[reply]

This is a quote from the biography Simone Weil by Francine du Plessix Gray, page 6:

In this ritualistically hygienic family, Simone, who had been born a month premature, spent a very sickly infancy and childhood. When the baby was six months old, her mother continued to breast-feed her while recovering from an emergency appendectomy. Simone began to lose a great deal of weight and grew very ill. When she was eleven months old Mme Weil was persuaded to wean her, but Simone, in an early struggle of conflicting wills, refused to eat from a spoon. She became so thin that several doctors gave her up for lost; until the age of two she did not grow in height or weight, and had to be fed mush from bottles into which increasingly large holes were pierced. Reflecting, as an adult, on these early crises (which might have played a role in the severe eating problems she developed in adolescence), Simone sometimes speculated that she had been "poisoned" in infancy by her mother's milk: "C'est pourquoi je suis tellement ratée," she'd say, "That's why I'm such a failure."

(I think a better translation for tellement ratée is "so messed up".) So apparently it was her mother who had the appendectomy. The techniques for maintaining asepsis were still under development in those days, but the concepts and philosophy were basically in place. --Lambiam 07:48, 20 September 2020 (UTC)[reply]

Thanks both. So maybe there is an error to fix in the Simone Weil biography, though maybe I'd want to consult another few sources first. Is the theory plausible, that Mme Weil's appendectomy (or some infection that caused the appendicitis) got toxins or pathogens into her milk? 2602:24A:DE47:BB20:50DE:F402:42A6:A17D (talk) 08:08, 20 September 2020 (UTC)[reply]

Some reliable sources say that the mother's milk affecting the child was the "family belief".^[2] Another expresses the hope that Simone's blaming her mother was "in jest".^[3] Interestingly, Simone Weil herself developed appendicitis at the age of three-and-a-half that was eventually, but apparently not quickly, attended to surgically, after which it took her a long time to convalesce.^[4] Sources differ on her age at the time of the operation; some say three, others four. --Lambiam 09:01, 20 September 2020 (UTC)[reply]

Surgery for appendicitis must have been fairly routine by 1909. Joseph Lister had pioneered aseptic surgery in the 1870s and his theories had been widely accepted by the 1890s. In 1902, Edward VII underwent surgery to treat what was widely reported as appendicitis but was described by his doctors as perityphlitis (which may well have been the same thing). The operation was carried out in the Music Room at Buckingham Palace two days before his planned coronation, which was postponed for six weeks. Alansplodge (talk) 16:01, 20 September 2020 (UTC)[reply]

Lister pioneered antiseptic surgery - basically dousing everything (including the open wound) in carbolic acid. That was a giant improvement to the previous technique of taking your unwashed hand from the gangrenous leg of one patient into the open body cavity of the next, then cover it up and hope for the best. But it had a number of negative side effects. In particular, carbolic acid is a fairly aggressive substance. The modern technique of aseptic surgery goes to great lengths to avoid microbiological contamination in the first place, not to try to control it after the fact. --Stephan Schulz (talk) 19:24, 21 September 2020 (UTC)[reply]

I'll try to find the link again but while looking around about this yesterday, I saw an article mentioning that appendicitis back then was usually treated by icing it down and hoping it got better. Appendectomy may have been reserved for very severe cases. 2602:24A:DE47:BB20:50DE:F402:42A6:A17D (talk) 23:02, 21 September 2020 (UTC)[reply]

September 21

Taxonomy of Euchile and Prosthechea

Higgins wrote in 2003 using genetic evidence that showed Euchile and Prosthechea are closely related. He made a case based on morphology that Euchile should be separate from Prosthechea. Current lists show Euchile renamed as Prosthechea. What was the basis of this decision? I can't find the relevant article. 167.95.98.207 (talk) 15:48, 21 September 2020 (UTC)[reply]

Can you say where you see these current lists? Our Prosthechea article just seems to say something similar to what you described. It seems we don't yet have an article on Euchile so it just redirects to Prosthechea I guess the best interim solution until someone creates one. Of course it can take a while for such proposals to be accepted, or they can never be but without knowing where you're seeing this it's IMO difficult to comment. Nil Einne (talk) 23:28, 21 September 2020 (UTC)[reply]

September 22

Moonwalk suits in c. -100°F and brutal katabatic wind on Earth

How effective is the Apollo moonwalking suit for Earth, Mars and LEO? It's very heavy and they walked in mild temps but if you're just sitting or lying down in 100 mph gusts on top of Everest in winter how would the discomfort vs continuous duration graph compare to Luna? Let's pretend there's a helipad and shack at the top that's room temperature and pressurized so you start feeling 100% but with lowlanders' oxygen needs. What about Antarctica's worst windchill under hurricane force, or good and bad Martian weather? Or those marathon modern spacewalks? Sagittarian Milky Way (talk) 00:12, 22 September 2020 (UTC)[reply]

Types of vets

If there are many types of physicians practicing human medicine, are there as many types of vets also? Our fellow mammals such as cats and dogs have organisms basically as complex as ours, after all. --Qnowledge (talk) 00:28, 22 September 2020 (UTC)[reply]

There are specialized parrot veterinarians, for sure. 146.200.128.134 (talk) 07:15, 22 September 2020 (UTC)[reply]

P vs V(isotherm) graph of real gas with critical temperature and critical pressure marked.

I want a P vs V graph for some real gas(say, CO₂), which shows the plots on a few temperatures, with plot at critical temperature as well, for comparison. I also want to have the representation of critical pressure on that very same graph. Also included should be the plot for Triple point temperature, with explanation for why the graph is that way. To sum up, there should also be a plot of the P vs V graph at Boyle's temperature.(fyi P= pressure, V= volume). Graph could be like this one: