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June 13

Size difference and premature birth

In mammal hybrids, if the mother's breed tends to be much smaller at birth than the father's, does this increase the risk of a premature birth? Of injury to the mother during birth? Of the offspring being malnourished due to insufficient lactation? Neon Merlin 04:50, 13 June 2018 (UTC)[reply]

Yes. Dystocia is one of the leading causes of stillbirth. DroneB (talk) 10:21, 13 June 2018 (UTC)[reply]

As an example, you could look at hinny, a cross between a male horse and a female donkey. Our article doesn’t say much, but maybe some references there would help. Loraof (talk) 16:19, 13 June 2018 (UTC)[reply]

That, along with mule, indicate the size of the offspring is influenced by the size of the mother. ←Baseball Bugs ^{What's up, Doc?} carrots→ 18:23, 13 June 2018 (UTC)[reply]

Lignite mines in Gujarat

Does anyone know a source for the annual production (or capacity) of the Gujarat Mineral Development Corporation lignite mines

Thanks in advance!--DCKH (talk) 12:12, 13 June 2018 (UTC)[reply]

No odor disinfectants

Is there any disinfectants I can use similar to lysol that I can mix with water to mop my floors or clean with that do not have an odor? I like lysol but the odor is too strong especially when mopping.--User777123 (talk) 19:54, 13 June 2018 (UTC)[reply]

If you just search Google or Amazon for "odorless disinfectant" you'll get a variety of results, though I can't personally vouch for any of them. A lot use dissolved silver as the disinfectant. Research has shown that at the appropriate concentrations, dissolved silver (usually as silver nanoparticles in a solution of water and sodium citrate) is effective as a disinfectant, but slow acting, often taking hours to fully sterilize a surface rather than minutes for harsher chemicals: [1]. Someguy1221 (talk) 23:17, 13 June 2018 (UTC)[reply]

Yes, but they won't be very useful for cleaning. The Lysol product that the OP is talking about is not just a disinfectant, it also contains solvents that loosen dirt from the surface. It won't be easy to find a powerful solvent that doesn't irritate the nasal cavity if it is inhaled. Looie496 (talk) 23:26, 13 June 2018 (UTC)[reply]

There are odorous but volatile disinfectants, which are odorless in the sense that they evaporate without leaving a smelly residue (contrary to perfumed disinfectants like Lysol). For home use I'd suggest sodium hypochlorite (or sodium percarbonate) or an acid like hydrochloric or acetic acid. Alkalis can be mixed with surfactants, acids usually cannot. I use a mixture of dishwashing detergent and sodium hypochlorite, it works great. --185.13.106.237 (talk) 23:35, 13 June 2018 (UTC)[reply]

Borax (sodium borate) is an odor-free, and readily available option, (it also has anti-fungal properties and repels ants). The Disinfectant article might be of interest. —2606:A000:1126:4CA:0:98F2:CFF6:1782 (talk) 05:22, 14 June 2018 (UTC)[reply]

Or use microfibre cloth with steam cleaning: [2]. --62.99.192.174 (talk) 15:52, 16 June 2018 (UTC)[reply]

June 14

Height above ground + distance South from Arctic Circle = Midnight Sun

Mt Denali, the highest peak in the U.S above 20000 ft above sea level and about 18000 ft tall, is 158 straight miles from Fairbanks, Alaska according to a Google search, but it can been seen from some parts of the city. That is key. Fairbanks according to our article about the city is 140 miles South of the Arctic Circle. According to our article, the sun’s disk is above the horizon for 21 hours and 49 minutes at the summer solstice. Therefore, Fairbanks doesn’t experience the midnight sun, but a short “white night” each day during this period. Height above the ground does affect daylight lenghth due to the curvature of the Earth and there are many examples. Given all these facts, let’s suppose that Mt Denali was right next to Fairbanks at the same latitude, 140 miles South of the Arctic Circle, and given that one can deduce that the visibility on a clear day would extend slightly beyond the Arctic Circle when looking North at the top of the summit if Mt Denali were to be at the same latitude as Fairbanks, would the summit get 1 to several days of the midnight sun around summer solstice, but of course not 1 to several days of polar night around winter solstice? Willminator (talk) 05:38, 14 June 2018 (UTC)[reply]

Doesn't the Continental Divide go north of Fairbanks? Mountains might block the Sun. What counts as sunset is kind of fuzzy though, pretending that stuff over sea level is air and everything below is water is often done even if your entire horizon is Lake Titicaca and you're treading water almost up to your eyeballs. Pretending you're levitating at Lake Titicaca altitude and surrounded by a sea level horizon with a lot of "distance from Earth"-induced horizon dip makes sunset times there a lot more inaccurate than just assuming the horizon's at lake elevation obviously. And even the Appalachian Range only 2km high can shield enough atmosphere from direct sunlight to make twilight noticeably darker than if that range didn't exist and it was all sea level like the simplified model so why not count mountains as being able to cause sunset? That'd cause a problem of what's the smallest thing that can cause night is though. Is it nighttime if a skyscraper hides the Sun at high noon?, or even your hand? Obviously not so where's the cutoff? Ignoring topography, Fairbanks is close enough to the Arctic Circle to cause midnight sun at Denali's elevation at the city center but ignoring topography though (sea level virtual horizon) Sagittarian Milky Way (talk) 07:04, 14 June 2018 (UTC)[reply]

Can "genetically identical" populations belong to different species?

Hello. In "Integrative Taxonomy Resolves Three New Cryptic Species of Small southern African Horseshoe Bats (Rhinolophus)", Taylor et al. admit that their study population of Rhinolophus is "genetically identical" to the existing species R. simulator, but they go ahead and recognise it as a distinct species anyway "on morphological and acoustic grounds". Is this reasoning scientifically solid? If so, why is it not applied to the numerous other species that display clear intra-specific variation, such as Canis lupus? It does seem odd to separate genetically identical populations into different species. Thanks.--Leptictidium (mt) 08:59, 14 June 2018 (UTC)[reply]

Genetically identical insofar as they sequenced, which was to a very limited extent. The paper in question, here, only obtained a partial sequence for a single mitochondrial gene, and took limited DNA sequencing from prior publications to use in their analysis. Their hypothesis is that possibly a small portion of the genome, mitochondrial and/or nuclear, is identical between different species due to rare and/or historical introgression events. But one would still expect the great bulk of the genomes to show long-term divergence from one another. That data has not been generated yet. Someguy1221 (talk) 10:25, 14 June 2018 (UTC)[reply]

Right. There is no such thing as populations that are fully genetically identical. Even the cells within a single individual body are not fully genetically identical. Looie496 (talk) 17:54, 14 June 2018 (UTC)[reply]

It may be possible to have genetically identical species produced via infectious speciation. (Wolbachia being the known example) [3] Biology never stops getting weirder. ;) Wnt (talk) 21:51, 15 June 2018 (UTC)[reply]

Human genetics

Can someone help me solve this problem?

In population that is in equilibrium there are four times as more dominant alleles than recessive ones. What is the frequency of the dominant trait in that population?

p² + 2pq + q²

p + q = 1

p = 4q

q = 1/5p

q = .2

p = .8

.2² = .04

1 - .04 = .96

Vs⁶ ₅⁰⁷ 13:00, 14 June 2018 (UTC)[reply]

It looks like you have some chaff there, but note that allele frequency is based on how many alleles are present, and you just said that, i.e. it's p. Usually it's slightly harder to figure out because you have to infer it from the phenotype rather than just being handed the information. Wnt (talk) 13:36, 14 June 2018 (UTC)[reply]

It's not about allele frequency, but rather phenotype frequency. So I guess I did correct there... Vs⁶ ₅⁰⁷ 14:48, 14 June 2018 (UTC)[reply]

Oooops, I misread that. Yeah, the dominant trait frequency is 1-0.2*0.2 as you say (at least, assuming the recessive isn't lethal balanced by some advantage for the heterozygote or something similarly wacky) Wnt (talk) 22:29, 14 June 2018 (UTC)[reply]

Plugging home appliances in the EU and the US

It seems to me that EU plugs allow the user to plug in a devices in two ways, but the US plugs only allow one way of plugging a device. The same discrepancy applies to other plug types, from other places. They are just examples. Why are they different? --Doroletho (talk) 16:48, 14 June 2018 (UTC)[reply]

Our AC power plugs and sockets article talks about all the different countries' standards. For example, a a non-reversible connection where one wire is hot and the other neutral guarantees to the device which is which. That can be a safety feature, for example, to reduce the likelihood that someone will touch something that is connected to the hot or how much of the device remains energized when a switch is "off". It wasn't that long ago that US also had reversible plugs and non-polarized outlets. DMacks (talk) 17:26, 14 June 2018 (UTC)[reply]

There a multiple standard of mains plugs in the EU, some of which are polarized, and some not. LongHairedFop (talk) 13:41, 16 June 2018 (UTC)[reply]

How do researchers make animals neglectful of their offspring?

I have heard of research experiments in which researchers compare caring animal parents and neglectful animal parents. My question is, how did the researchers manipulate this? Is it some sort of gene that they knock out? Do they train animals to behave a certain way? SSS (talk) 19:31, 14 June 2018 (UTC)[reply]

There are always some animals that neglect their offspring. Ruslik_Zero 20:10, 14 June 2018 (UTC)[reply]

In some species (including rodents and sheep) animals will neglect their offspring if they don't smell right. Looie496 (talk) 22:09, 14 June 2018 (UTC)[reply]

Treatment of mothers with naloxone or genetic mutations that block pheromone receptors will do it. [4] Wnt (talk) 22:31, 14 June 2018 (UTC)[reply]

Simply separating the parents from the offspring seems like the simplest way to ensure parental neglect. CodeTalker (talk) 23:26, 14 June 2018 (UTC)[reply]

Identify unknown mushroom species

I would like some help identifying these species. These first two photos are of a mushroom that is very similar to a garden-variety mushroom but it is definitely not the edible kind. I found it growing on tbe U.S. Courthouse lawn, and it is really quite toxic. It has a strong earthy or musty odor with something faintly pungent and acrid to it, which immediately caused my eyes to dilate and my stomach to cramp up, and I almost passed unconscious that afternoon and I woke up in the middle of the night with chills and leg cramps. That's just the smell. I really wouldn't eat it. My eyelid is still twitching with an odd tic from that and I heard the neighbor's dog went blind sniffing this kind of mushroom.

The mushroom below looks like some kind of morel to me. I'm not really sure, but it has an overpowering foul odor to it. It was growing on a street corner downtown.

I'm suspecting the spores are spread by the sorry girls and frat boys at University of Alaska Fairbanks who frequent the aforementioned courthouse demanding a total gun ban certiorari in case one of the sorry girls has to dump her boyfriend and all the sisters need a campus police escort to make it safely back to their dorm rooms after their mental health counseling appointments. Any positive I.D.? Need more info. justinacolmena (talk) 20:55, 14 June 2018 (UTC)[reply]

It could be Agaricus_xanthodermus which looks like a very large Champignon and smells of phenol. The last picture can be the same when young and by dry weather but I think more for example of some Tricholoma or Lepista. Morel is completely different.194.174.76.21 (talk) 14:42, 15 June 2018 (UTC) Marco Pagliero Berlin[reply]

No yellow. No phenol smell. Head is thicker and rounder. Absolutely no one is going to eat this mushroom without ill effects. The last one is not the same as the others. It has a completely different smell. Tricholoma or Lepista are too flat-headed. The shape of this one is pointy-headed like the morel, but it has a droopy, rain-split cap which the morel lacks. False morel? Probably not even. justinacolmena (talk) 18:50, 16 June 2018 (UTC)[reply]

But if you're eating unidentified mushrooms, you really should reconsider your priorities. --jpgordon^{𝄢𝄆 𝄐𝄇} 17:26, 15 June 2018 (UTC)[reply]

Excuse me. You must have been high on drugs if you thought I was "eating" this mushroom and still alive today. justinacolmena (talk) 18:50, 16 June 2018 (UTC)[reply]

June 15

Phobos orbital height - I must be missing something

Phobos orbits at a height above the Martian datum of 6km. Olympus Mons is 26km in height. Maybe Phobos has a stable orbit and won't collide with it, but I feel like I'm missing something or misinterpreting the data? Surely Phobos can't really be that low? Dr-ziego (talk) 12:10, 15 June 2018 (UTC)[reply]

Where did you get the idea that Phobos orbits 6 km above Mars? It's about 6,000 km, per our article. Matt Deres (talk) 12:19, 15 June 2018 (UTC)[reply]

It'll collide eventually causing a titanic explosion. Sagittarian Milky Way (talk) 13:48, 15 June 2018 (UTC)[reply]

Phobos has an orbital inclination of 1.093° degrees, relative to the Martian equator. Olympus Mons is located 18.65° North of the Martian equator. Therefore, Phobos never overflies Olympus Mons. LongHairedFop (talk) 13:39, 16 June 2018 (UTC)[reply]

Oh right, that too. Sagittarian Milky Way (talk) 13:54, 16 June 2018 (UTC)[reply]

On another hand, Pavonis Mons is on the equator. —Tamfang (talk) 07:29, 17 June 2018 (UTC)[reply]

Pavonis is 1.48°North, so Phobos doesn't overfly it. However, IIRC, the inclination of moon's orbits can vary over times, so eventually Phobos will overfly it. LongHairedFop (talk) 22:05, 17 June 2018 (UTC)[reply]

What airliner requires the most runway at over 40 Celsius and 0 to 1000 feet elevation?

I've heard it might not actually be the Airbus A380. Sagittarian Milky Way (talk) 13:44, 15 June 2018 (UTC)[reply]

For passenger aircraft, it is the Airbus A380. If you look into cargo planes, the AN-225 Mriya requires more (about 9,000 ft for the A300 and 10,000 for the Mriya). 209.149.113.5 (talk) 14:00, 15 June 2018 (UTC)[reply]

Isn't there a big difference in minimum recommended runway between frigid, low ladenness and good weather and hot, highly laden and unfavorable wind? Or landing in tropical rain while highly laden for landing lengths? Sagittarian Milky Way (talk) 14:22, 15 June 2018 (UTC)[reply]

Yes. A pilot should use the temperature, humidity, wind speed/direction, and air pressure to calculate the "density altitude", which is the altitude the aircraft appears to be at if the conditions were optimal. Then, with the density altitude, the minimum required runway length is calculated. There are cases where normal airports shut down runways because they are too short for the calculated density altitude. Minimum length can get very long. In Tibet, there is a runway that is at least 3 miles long - and sometimes it can get too short. 209.149.113.5 (talk) 14:49, 15 June 2018 (UTC)[reply]

^{[citation needed]} This isn't under the above conditions and also doesn't seem to clearly specify it's referring to the rare 747-8I (passenger) variant but for "minimum requirements that apply to an aircraft at Maximum Certified Takeoff Weight (MTOW), taking off at sea level under ISA condition" gives Airbus A380-800 2900 metres and Boeing 747-8 3050 metres [5] Nil Einne (talk) 16:44, 16 June 2018 (UTC)[reply]

This quick guide also gives similar figures for the MLW [6]. Actually the 747-400 is the also higher. Nil Einne (talk) 16:59, 16 June 2018 (UTC)[reply]

I think you should be able to work out from these documents if the above is correct for the specified conditions [7] [8] Nil Einne (talk) 17:11, 16 June 2018 (UTC)[reply]

So it appears that at maximum takeoff weight, 0 pressure altitude and 30C sea level equivalent (it doesn't give more) the 747-8I needs a longer takeoff than the A-380-800 but it's roughly the same at 1,000 feet and the other way around above that. Sagittarian Milky Way (talk) 22:30, 16 June 2018 (UTC)[reply]

Short Question About Astronomy

The occurrence of the "Number of solar noons (middays)" is always equal to "Number of solar midnights"

The diagram (not to the scale) on the right-hand side depicts the path traced by the earth for day and night in its orbit (either circular or elliptical) around the sun. Any point on the outer circle represents solar midnight while on inner circle solar noon. The length of an outer circle is greater than the length of the inner circle and hence Arc I > Arc II. This means the appearance of midnight points (anti noon) are more than middays points (solar noon) when the earth revolves around the sun in its orbit – Any special reasons

As # of midnights = # of solar noons when the length of arc I = length of arc II but since arc I > arc II, therefore

Are solar noons and solar midnights equal in numbers in the arc I and arc II or after the completion of 4 years?--Eclectic Eccentric Kamikaze (talk) 13:57, 15 June 2018 (UTC)[reply]

... or another way of looking at the situation is that the midnight point is always moving faster than the noon point. Dbfirs 14:46, 15 June 2018 (UTC)[reply]

The first thing to bear in mind is tidal force. If the Earth did not rotate, or more precisely, were tidally locked, its outer edge would have to revolve faster than the inner edge, like a phonograph record. This doesn't precisely match the expected orbital period, so there are tides raised by the Sun - the other part of the planet gets a gentle nudge like it should fly off to space, while the inner has a gentle nudge to fall toward the Sun, though of course if separated somehow neither would get far before returning where they were in some sort of elliptical orbit, sans planetary integrity. So the point is, the "midnight" part of Earth is always going a bit faster to make up the distance. Wnt (talk) 18:48, 15 June 2018 (UTC)[reply]

In other words: there are just as many middays on the inner circle as midnights on the outer one, but space (not time!) between midnights is a bit larger. Right? 194.174.76.21 (talk) 10:15, 18 June 2018 (UTC) Marco Pagliero Berlin[reply]

With rotating systems, it is often more useful to consider things in terms of angles, rather than distances. The earth is moving 2pi radians per year. There are 365.25(ish) middays and midnights for a point on the surface in each year. Therefore, each successive midday is separated by 2pi/365.25, and the same for each successive midnight. The midnights are further out, so the linear distance between them is greater, but that's not relevant here. MChesterMC (talk) 10:31, 18 June 2018 (UTC)[reply]

Does it mean time dilate during nighttime when the earth orbits the sun? - The Earth spins at the same speed no matter if it's day or night.

Any point on the outer circle, which represents midnight if connected to the center of the sun via a straight line passes through the noon (inner circle). When there is midnight, there is a noon, therefore, duration/occurrence of midnights must be equivalent to the duration/occurrence of noons and hence their lengths.50.66.1.32 (talk) 18:20, 18 June 2018 (UTC)eek[reply]

Attribution note - the diagrams at Talk:Season#Earth's Rotation and its Orbital Motion were uploaded by Eclectic Eccentric Kamikaze, and not as stated by Dbfirs. Just to clear up any possible misconceptions from the present discussion, clocks set to mean solar time and sundials when adjusted to mean solar time measure time at the same rate whatever the time of day and wherever on the surface of the Earth they may be located. 86.132.186.246 (talk) 13:26, 19 June 2018 (UTC)[reply]

The statement I made was about the text, not the diagrams, but I agree with your comment about normal clocks. A sundial could be adjusted to mean solar time by using a clock. Dbfirs 19:19, 19 June 2018 (UTC)[reply]

Bees and butterflies question

There has been an abortion debate in Argentina in those days, as the Congress is discussing a bill to legalize it. But there is a part of the text of the bill that I did not understand: translated to English, instead of talking about women, it talks about "women and people that may become pregnant". It feels weird having to ask this, but does such wording make sense, can someone other than a woman become pregnant? I know that there are transsexual people and sex reassignment surgery, but is that enough to make a person that was once a man to become pregnant and deliver a baby? Did that ever happened? Or is it just political correctness gone mad? Cambalachero (talk) 19:17, 15 June 2018 (UTC)[reply]

"No results found for 'women and people that may become pregnant'".[9] Maybe it is not available in English. Can you post the text in the appropriate language? Bus stop (talk) 19:25, 15 June 2018 (UTC)[reply]

If "women" is taken to mean "adult females" then of course other people who may become pregnant are females below the age of adulthood. DuncanHill (talk) 19:28, 15 June 2018 (UTC)[reply]

Also, women can consider themselves men and still become pregnant. Bus stop (talk) 19:40, 15 June 2018 (UTC)[reply]

That's under transgender pregnancy. Also, some people regard themselves as a third sex, etc. My feeling is that "women and people who may become pregnant" is inelegant; one (presumably the latter) should suffice for most intentions. True male pregnancy in humans is probably not far off anyway, so "people" would seem like a reasonable replacement in a forward-looking statement. Wnt (talk) 21:45, 15 June 2018 (UTC)[reply]

It's downright criminal that every news outlet to discuss this bill doesn't tell us what it's frickin' name is!. Makes it very hard to search for. Still looking - I was hoping to just read the Spanish version directly. Someguy1221 (talk) 22:16, 15 June 2018 (UTC)[reply]

OK, I think this is the bill that was just voted on, but I don't see what the OP is referring to anywhere. Someguy1221 (talk) 22:54, 15 June 2018 (UTC)[reply]

The term in Spanish is "mujeres y personas gestantes". I have not found a single-word translation of "gestante" to English, so I made the translation myself. The word would be an adjetive for a living being with the hability of becoming pregnant. In any case, I was not asking about the bill (that's a local bill in a Spanish-speaking country, after all; I do not expect many people abroad to be following those news events) but about the pregnancy aspect. If I understood the article, barring discussions of what would be theoretically possible there are no actual cases of children born from male-to-female transgender people. There are some named cases of children born from female-to-male transgender people (that is, someone who was born as a woman, and retains all the required organs), but how often does that happen? Do they get pregnant as easily and frequently as straight women, or are those special fortunate cases? Cambalachero (talk) 00:36, 16 June 2018 (UTC)[reply]

[10]. It has apparently been the standard language used by the Ministry of Health since 2015 in cases regarding abortion, and explicitly with transmen and similar situations in mind. As for how often this happens, we have an article on Transgender pregnancy, but no statistics, and I also could not find any statistics on this in the scientific/medical literature. I would assume that it is quite rare. However, as to how easy it is, that depends. The majority of transmen do not undergo sex reassignment, leaving them physically as capable of conceiving and bearing a child as they would be otherwise. There is insufficient data to say what the long-term effects of hormone transition therapy are on the fertility of transmen. It's believed that such therapy impairs fertility, especially while it is being taken (and may also impact fetal development), but it's not clear to what extent. There is a review on the subject here, but mostly it just clarifies that we don't know a lot. Someguy1221 (talk) 00:53, 16 June 2018 (UTC)[reply]

"Pregnant people" is also used more and more in English these days, rather than the phrase "pregnant women" that was nearly exclusively used historically. Some examples: [11] [12] [13] [14]

Something of an aside, but "bees and butterflies"? Are they the Argentine equivalent of the birds and the bees? DuncanHill (talk) 00:59, 16 June 2018 (UTC)[reply]

The equivalent of Spanish gestante is English gestant from gestation, which is a rather unsual word compared to pregnant. --62.99.192.174 (talk) 23:16, 16 June 2018 (UTC)[reply]

I am reminded of the term Embarazada. Bus stop (talk) 23:25, 16 June 2018 (UTC)[reply]

June 16

if the half-life of estradiol cypionate is around 8 days, what would be the half life of estradiol dicypionate?

Is there a rule of thumb for estimating the half-life depot steroid medications if both hydroxyl groups on a steroid are esterified versus just one hydroxyl group? I note that estradiol dipropionate is an ester described as having a relatively long half-life, but this article seems to imply that diesterification can lengthen the half-life by two to eightfold, since before the innovation of estradiol dipropionate, most esters were injected 2-4 times a week, now could be injected once every 1-2 weeks. Yanping Nora Soong (talk) 04:12, 16 June 2018 (UTC)[reply]

According to Ullmann's "Hormones", esterification of estrogens increases their duration of action. A similar approach would be increasing the carboxylic acid chain length (like in the series Estradiol valerate, Estradiol enanthate, Estradiol cypionate). Furthermore, alkylation of estradiol derivatives at position 17 (ethinyl estradiol, quinestrol) increases their oral activity many times. --62.99.192.174 (talk) 23:39, 16 June 2018 (UTC)[reply]

This doesn't answer my question. I already know that!! I can't figure out how to apply Bates' equation in radioactive decay for a decay chain to this problem. Yanping Nora Soong (talk) 01:30, 17 June 2018 (UTC)[reply]

Do I add the half lives?? Do I multiply the half lives? I've tried all sorts of approximations and differential equations. Is the half life more like 16 days or 64 days?? The problem with the Bates equation is that it does a poor job when k1 and k2 are very close in magnitude, because you have to divide zero over zero. Agh! Yanping Nora Soong (talk) 01:33, 17 June 2018 (UTC)[reply]

I thought you were trying to deduce the pharmacokinetics of some hypothetical estradiol esters. But is it first order, zero order, nonlinear? First there is hydrolysis of the ester, then there is the metabolism of the estradiol, each of which seem to follow different kinetics, also depending on the route of administration. A Google search for "estradiol ester pharmacokinetics" and "estradiol ester metabolism kinetics" throws up lots of interesting hits. --62.99.192.174 (talk) 02:12, 17 June 2018 (UTC)[reply]

This is a a depot *diester* prodrug. Both functional groups must be removed to produce the active drug. I'm not interested in monoester pharmacokinetics and I already did the relevant research, hence why I'm here. I also tutor biochemistry... Also why aren't people reading my entire question? :( I really need help with the Bateman equation. I don't need a lecture on routes of administration for a depot formulation? Yanping Nora Soong (talk) 05:19, 17 June 2018 (UTC)[reply]

@Yanping Nora Soong: The Bateman formula gets very complicated for intermediates in a decay chain. However, the stability of the first isotope, or compound, has nothing to do with anything that comes afterward (some of those pi terms where you multiply a series of numbers don't have anything to multiply). In this case it probably is easier to redo the derivation of the math than to figure out what the formula means. You are looking at estradiol dicypionate -> estradiol cypionate -> estradiol, I think. Now do you already know the biological activity and the rate of decay for each of these intermediates? Then we can go over it. But if your assumption is that the first ester is broken at the same rate as the second, well, to begin with, we have no idea if that's true since this is biology (and chemistry...), but if it is true, then half-life of estradiol cypionate should logically be the point where just 25% of the estradiol dicypionate has been broken down to estradiol (a 50/50 chance for each bond), and two half-lives for estradiol (that would leave 25% left) would correspond to leaving 1-0.75*0.75 = 44% of the estradiol dicypionate or cypionate left. Note I'm not expecting a true half-life relationship for the "E1-2C -> estradiol decay" starting with E2C because the nature of "E1-2C" will change over time. Wnt (talk) 13:28, 17 June 2018 (UTC)[reply]

1 AU

How thick is the belt? What is the height and width? 123.108.246.27 (talk) 18:46, 16 June 2018 (UTC)[reply]

What belt? ←Baseball Bugs ^{What's up, Doc?} carrots→ 19:23, 16 June 2018 (UTC)[reply]

See Astronomical unit. Ian.thomson (talk) 19:45, 16 June 2018 (UTC)[reply]

See also Kuiper belt, possibly. If by 'width' the OP means 'span of distances from the Sun, then that article suggests 30–50 AU, hence a 'width' of about 20 AU. Thickness and height presumably mean maximum (known) distance span perpendicular to the Ecliptic plane, which the article does not specifically state, but applying simple maths (I actually drew a diagram) to the stated orbital inclinations of "up to 30°" I come up with about 35 AU either side of the ecliptic at 50 AU out, so about 70 AU. Doubtless others can find Reliable Sources for an answer better than my Synthesis/OR. {The poster formerly known as 87.81.230.195} 2.125.75.224 (talk) 09:46, 20 June 2018 (UTC)[reply]

Retaining carbonation

Suppose I want to open a cold, carbonated beverage and have it retain the maximum possible carbonation when I take the first sip, right after the pressure has dropped to atmospheric. Holding constant things like starting temperature and without previous agitation, do I lose less carbonation by the most sudden pressure drop, like popping the cap on a glass bottle, or by lowering the pressure as slowly as possible, like v-e-r-y slowly unscrewing a screw cap, and letting the pressure drop infinitesimally slowly? Or would just unscrewing a cap at a typical fast rate retain the most bubble? What is the scientific basis for the conclusion? Edison (talk) 19:06, 16 June 2018 (UTC)[reply]

If you open the cap as slowly as possible, the bottle will have been open for a long time, and will thus be entirely flat. For openings that last no more than a few seconds, I don't think it makes any appreciable difference, except that if you actually let the gas undergo free expansion it won't cool off and will thus keep the interior a bit warmer (which accelerates loss of the dissolved gas). --Tardis (talk) 21:38, 16 June 2018 (UTC)[reply]

I guess my phrasing left open the prospect of taking an hour or more to unscrew the cap, leaving the pop warm and flat. In practice, I might do it “fast” in one-half second from first escape of pressure up to 10 seconds to very slowly release the pressure from the time it is first heard hissing out. I wondered if a sudden drop, like rapid unscrewing or popping a metal cap from a glass bottle would produce a shock causing a greater loss of carbonation, similar to shaking it or setting it down hard before opening it, which clearly causes a massive loss of carbonation. As I asked initially, what topics in chemistry address the issue of the rate at which gas dissolved in liquid is liberated in a solution at atmospheric pressure. From experiments done long ago I think the volume of carbon dioxide might initially be equal to or even greater than the volume of the liquid, which itself is amazing. Edison (talk) 14:12, 17 June 2018 (UTC)[reply]

From a knowledge of brewing and beverages I can confirm your last point. The volume of CO₂ per volume (of liquid) is for real ale in good condition considered to be a little over 1. However, in other beverages it can be several times this. To quote from Beverages: Technology, Chemistry and Microbiology by Alan H. Varnam & Jane P Sutherland (Chapman & Hall 1994), p 92: "The optimum level of carbonation varies according to the flavour and perceived character of the different drinks. In general terms, fruit drinks are carbonated to a low level (ca. 1 volume CO₂), colas, ginger beer, alcohol-containing drinks, etc., to a medium level (2-3 volumes CO₂) and mixer drinks such as tonic water and ginger ale to a high level (ca. 4.5 volumes), to allow for dilutions in the non-carbonated liquor. Soda water filled into syphons, however, contains up to 6 volumes of CO₂ to maintain internal pressure during use."

My personal experience (OR warning!) of opening bottles of carbonated drinks with a higher than usual overpressure, perhaps due to warming, agitation, prolonged secondary fermentation in the container (which for real ale is by definition mandatory), or a combination of these, is that rapid opening may lead to immediate excessive foaming (aka 'fobbing') but that this can be mitigated by slower release of pressure taking at least several seconds – longer than that might reduce the over-foaming even more, but who would have the patience? {The poster formerly known as 87.81.230.195} 2.125.75.224 (talk) 13:23, 18 June 2018 (UTC)[reply]

Mystery tide pool creature (Southern California)

What is this thing? I assume it's just the mouth/siphon of something hiding in a rock crevice, and it was shooting jets of water. 169.228.163.250 (talk) 20:10, 16 June 2018 (UTC)[reply]

Dejavacrapped link: [15] Every pageview you make on the internet that Google doesn't know about is a theft, and therefore, a revolutionary act. Wnt (talk) 22:21, 16 June 2018 (UTC)[reply]

Kind of gross looking. See Trypophobia. ←Baseball Bugs ^{What's up, Doc?} carrots→ 23:41, 16 June 2018 (UTC)[reply]

I see the extremities of many thin tentacles sorrounding some thick ones sorrounding a mouth. It seems to me to be a retracted sea anemone waiting for high tide. Some see anemones do live in rock cavities, although I don't know whether they can dig one themselves. 194.174.76.21 (talk) 15:49, 18 June 2018 (UTC) Marco Pagliero Berlin[reply]

June 17

Bateman equation

Suppose A decays to B via first order rate constant k1 and B decays to C via first order rate constant k2. All the treatments of the Bateman equation in radioactive decay I've found assume that k1 is never close in magnitude to k2. This is really frustrating because I want to use it to approximately model to my pharmacological diester duration of action problem. If k1 = k2 (you would think this is a simple situation!!) then you get division of zero over zero and l'Hôpital's rule doesn't solve the problem. (I've even tried using the ratio k2/k1). Help? If k1=k2=0.086 (corresponding to half lives of 8 days each), then how much time does it take for half of A to break down to C? Is it more like 16 days or 64 days? Yanping Nora Soong (talk) 01:43, 17 June 2018 (UTC)[reply]

I get about 18 days, just using a secret engineer's method (a spreadsheet model, renders most calculus redundant). The mass of B is a maximum at about day 11. Greglocock (talk) 06:01, 17 June 2018 (UTC)[reply]

In your problem when

k_{1}=k_{2}=k

and

A(0)=1

,

B(0)=0

and

C(0)=0

C(t)=1-e^{-kt}(kt+1)

.

which, when

C=1/2

, leads to

kt\approx 1.65

and

t\approx 1.65/0.086=19.2

days. Ruslik_Zero 10:19, 17 June 2018 (UTC)[reply]

Thank you!!!!! I am also going to write a script for a Monte Carlo method later. Now I suspect because of increased steric bulk that k2 is slightly bigger than k1 (but around the same order of magnitude), but the problem k1=k2 was bugging me because I was worried that the half-life was unbounded. It turns out that HRT users report that a med that includes this diester (Climacteron) is injected every 30 days (although manufacturer monograph says 4-8 weeks). Yanping Nora Soong (talk) 17:21, 17 June 2018 (UTC)[reply]

Your problem is the repeated eigenvalue issue in linear differential equations. It’s usually as far as i know solved by multiplying C1e^kt by t and then adding C2e^kt, which is the same thing really as what the engineer said above. Something similar in decaying harmonic motion is called “criticallydamped.” — Preceding unsigned comment added by 67.128.146.22 (talk) 18:10, 17 June 2018 (UTC)[reply]

Hmmmm... per my logic in the last question section I would think that if the half-life of each of two bonds is 8 days, then after 19.2 days, each bond is only unbroken 19% of the time, so the amount with both broken at that point is 81%*81% = 66%. I think the difference in the math above is that you suppose the half-life of A is the same as the half-life of B -- but in the previous question A has *two* ester bonds either of which can be broken while B just has one, so we'd expect a different rate constant. Again, I don't really know the stability of A and it doesn't have to be half of B or any other particular value, but I just thought I should point this out. Wnt (talk) 21:42, 17 June 2018 (UTC)[reply]

I've realized this -- there are two intermediates -- but I made that approximation to try to obtain a value that made sense. I saw a "complex" chain treatment that looked like my problem, and I'll try a Monte Carlo method later. Thank you so much!!! Yanping Nora Soong (talk) 02:04, 18 June 2018 (UTC)[reply]

For the complete math: the original problem is a "simple" matrix differential equation ${\begin{bmatrix}{\dot {A}}\\{\dot {B}}\end{bmatrix}}={\begin{bmatrix}-k_{1}&0\\k_{1}&-k_{2}\end{bmatrix}}{\begin{bmatrix}A\\B\end{bmatrix}}$ (add a column/row if you want C), which does have an analytical solution in the general case. Tigraan^{Click here to contact me} 11:47, 18 June 2018 (UTC)[reply]

Dividing line between angina and heart attack

Doesn't angina always involve at least some loss of oxygen to the heart, and therefore a possibility of damage? So if a self-interested hospital wants to increase revenue, what’s to stop the hospital from calling a case of angina a heart attack? Is there news or opinions in media about this as a conflict of interest? Thanks 67.128.146.22 (talk) 10:01, 17 June 2018 (UTC)[reply]

There are tons of literature about differential diagnosis of heart attack and angina pectoris. You can search yourself in Google. Ruslik_Zero 12:23, 17 June 2018 (UTC)[reply]

”you can search yourself in Google” is a weird response for a volunteer at reference desk.67.128.146.22 (talk) 17:57, 17 June 2018 (UTC)[reply]

At an academic reference desk, the answer is sometimes "here are the search terms you need; look through them, and feel free to come back if you want further assistance". Nyttend (talk) 01:10, 18 June 2018 (UTC)[reply]

(I am assuming, based on your IP address, that you're interested in the U.S. "healthcare system".) Most U.S. hospitals bill on a fee-for-service basis; that is, the charges are based on the services and procedures performed, not on the specific diagnosis attached to a particular patient. If a patient undergoes cardiac catheterization, the bill is the same whether the diagnosis is "angina" or "infarct". (That oversimplifies a bit; in practice the billing goes into rather a lot of arcane detail, with separate charges for staff, operating room time, drugs, instruments, tests, etc.)

Now, if a hospital makes a habit of over-diagnosing and thereby performing unnecessary tests and procedures, pushback happens in a number of ways and places. Insurance companies tend to notice when one hospital seems to have unusual patterns of diagnosis and treatment, and will start to deny reimbursements that aren't accompanied by sufficient documentary evidence. Overdiagnosis to increase billings is a gross breach of medical ethics, and can lead to both civil and criminal penalties for the parties involved.

(More common and more difficult to deal with is over-testing and over-treatment done in good faith. For physicians, it's hard – and sometimes legally risky – to tell a patient that expensive tests aren't necessary; it's hard to tell a patient that the best way to treat their condition is sometimes to do nothing. This New Yorker article is an accessible overview.) TenOfAllTrades(talk) 15:00, 17 June 2018 (UTC::thanks good response67.128.146.22 (talk) 17:57, 17 June 2018 (UTC)[reply]

June 18

Terminal dehydration mechanism

I looked for this on Google, but all the results I saw were too technical for me to understand.

If you die of terminal dehydration, what's typically the reason of death? Is it dehydration itself (and in particular, what fatal effect does extreme dehydration cause), or is it some side thing, like a simple illness (e.g. the sufficiently dehydrated immune system can't function properly), or urea poisoning (you don't have enough water to urinate, so you build up urea to a fatal level), or something else? Nyttend (talk) 01:07, 18 June 2018 (UTC)[reply]

I dont have expert medical knownledge. Good chance someone else can answer this way better but i think i have the basics right and you wrote that you didnt want tomuch detail anyway: It depends on your body's condition, training and your surrounding. In a hot area you will fail to regulate your body temperature, overheat and then multiple vital organs may fail. If you are used to living in a hot desert your body will adapt and you likely already have allot of experience with dehydration. So you may survive a level of dehydration that would kill anyone else even in an earlier stage. In a mild climate your kidneys will likely stop working first and as a result you slowly become "toxic", which will affect other organs. So the typical reason of death is some (or multiple) Organ dysfunction(s). Because many organs have a vital function its hard to pin the cause down to one. --Kharon (talk) 02:35, 18 June 2018 (UTC)[reply]

Giordano Bruno crater

Per our article, Giordano Bruno (crater) is on the far side of the Moon "that always faces away from Earth", so how five Canterbury monks could have observed the crater's formation? Thanks. 212.180.235.46 (talk) 07:01, 18 June 2018 (UTC)[reply]

There is no actual evidence that they did, but the location of the crater isn't the real issue. It's just behind the limb, and from our article "At this location it lies in an area that can be viewed during a favorable (sic) libration". Also, debris would be thrown much higher, out past the limb, even if the impact itself wouldn't be visible. Fgf10 (talk) 08:02, 18 June 2018 (UTC)[reply]

Let's not bicker and argue about who killed who.

Or favourable (sic). ←Baseball Bugs ^{What's up, Doc?} carrots→ 14:07, 18 June 2018 (UTC)[reply]

Not what the article says, so would be an incorrect quote. Do you have anything factual to add to my answer? Fgf10 (talk) 17:31, 18 June 2018 (UT

Can you restrain yourself from gratuitously provoking Americans in an otherwise useful answer? --Trovatore (talk) 17:36, 18 June 2018 (UTC)[reply]

What on earth did I say that was a gratuitous provocation?! I gave a correct and useful answer to the OP. Is that against the Trump ethos or something? Fgf10 (talk) 18:37, 18 June 2018 (UTC)[reply]

Favorable is not (sic) in America. I'm not offended but some might be. Sagittarian Milky Way (talk) 18:47, 18 June 2018 (UTC)[reply]

Really? That's it? I would expect Americans do to exactly the same the other way around. That's how language works. Christ, you people need to grow some thicker skin. Fgf10 (talk) 19:19, 18 June 2018 (UTC)[reply]

Probably only the unusually nationalistic would be offended. Sagittarian Milky Way (talk) 19:43, 18 June 2018 (UTC)[reply]

Or would feel the need to say (sic) after an acceptable spelling. ←Baseball Bugs ^{What's up, Doc?} carrots→ 19:45, 18 June 2018 (UTC)[reply]

It's not acceptable in Fgf10's language, which is British English. Why do you assume that he/she must be familiar with all spellings in a foreign language, namely American English? {The poster formerly known as 87.981.230.195} 2.125.75.224 (talk) 14:45, 19 June 2018 (UTC)[reply]

English is English. It was originally "-or". The Brits changed it.[16] ←Baseball Bugs ^{What's up, Doc?} carrots→ 20:44, 19 June 2018 (UTC)[reply]

June 19

Viscosity from DFT (VASP) using the Green-Kubo relation

Hello! In this paper https://pdfs.semanticscholar.org/e8a2/02f25555cd8c4f947bbbdff5a61a0ea0efd2.pdf the authors use VASP to determine MgSiO3 viscosity using the Green-Kubo relation $\eta ={\frac {V}{3k_{\rm {B}}T}}\int _{0}\left\langle \sum \limits _{i<j}\sigma _{ij}(t+t_{0}).\sigma _{ij}(t_{0})\right\rangle dt$ where $\sigma _{ij}$ (i and j = x, y, z) is the stress tensor, t is time and t0 is the time origin. But I've seen other papers use: $\eta ={\frac {V}{3k_{\rm {B}}T}}\int _{0}^{\infty }dt\left\langle P_{xy}(t)P_{xy}(0)\right\rangle$ , where $P_{xy}$ is the off-diagonal component of the stress tensor $P_{\alpha \beta }$ ( α and β are Cartesian components).

OK, so clearly these are essentially exactly the same equation but the second uses only the xy component whereas the first seems to suggest a summation? So which is correct?

Also, VASP outputs the stress tensor components as XX YY ZZ XY YZ ZX. So which of these should I use to input into the Green-Kubo equation? And are there missing components? what about yx, zx, yx?

Thanks in advance. Polyamorph (talk) 15:01, 19 June 2018 (UTC)[reply]

For your second question, per our article Cauchy stress tensor, the stress tensor is symmetric, thus having only six independent stress components, instead of the original nine, see also Stress_(mechanics)#General_stress. For the first question, I am not sure; it could be that only one off-diagonal component is nonzero in the context (for instance in a shear flow where water flows in from (x=±Inf,y=0) and out from (x=0,y=±Inf), and the flow is uniform across z), as is the case in many viscosity-measurement experiments; or it could be the Einstein notation by taking x and y as free variables (but then a factor 1/2 is missing). Tigraan^{Click here to contact me} 16:49, 19 June 2018 (UTC)[reply]

I think that in both case sum of off-diagonal components is implied. Ruslik_Zero 20:16, 19 June 2018 (UTC)[reply]

Aerial refueling a commercial jet?

Apparently aerial refueling doesn't make much economic sense for commercial jets. [17] But suppose radar operators were scanning for MH370 on the day of its disappearance and after almost all hope (and fuel) is lost, a passenger had gotten on the radio and said the pilots are dead, but some of us woke up, where are we, all we see down there is water!... Is there any conceivable way that some fast military aircraft swoops up from a carrier and slows down, and we see a boom projecting forward from it or a hose dangling down from in front of the wing, with a hard-bitten soldier or a decently designed robot on the end that can unscrew a gas cap and start pouring gas into the plane's tank so that the passengers don't end their adventure in the Indian Ocean? Or is it completely hopeless? Wnt (talk) 17:38, 19 June 2018 (UTC)[reply]

Bear in mind that tanker planes aren't particularly fast; they're primarily freight aircraft. The first picture at aerial refueling shows a Boeing KC-135 Stratotanker, with a cruising speed of 530 mph and a maximum speed of 580 mph, while another picture shows an Ilyushin Il-78, whose maximum speed is similar to the cruising speed of the Stratotanker. If the plane's virtually out of fuel, there's no way you can get a tanker on-site unless it's already really nearby. This assumes that the airliner is comparatively close to land, or that it's not far from a carrier-based tanker. Also see Aerial_refueling#Buddy_store, which notes that carrier groups don't generally have tanker aircraft, so the chance of finding a carrier-based tanker is even tinier. Nyttend (talk) 17:50, 19 June 2018 (UTC)[reply]

PS, see Gimli Glider and its paragraph beginning with "On airliners the size of the 767"; a recent commercial airliner without fuel is exceptionally difficult to control, even by professionals, since a Ram air turbine doesn't have much power compared to jet engines. Nyttend (talk) 17:58, 19 June 2018 (UTC)[reply]

Modern airlines are set up for single-point refueling, also known as underwing fueling, which requires a fairly complex set of motions when connecting the refueling nozzle. To add another level of complexity, the refueling point is commonly found under an access panel, which will either be held shut by the slipstream or act as a impromptu air brake when opened. So ignoring the logistics of getting the tanker in the right place at the right time... once you have it there, it'll be near impossible to connect and refuel on a commercial airlinger not designed with air-to-air-refueling in mind. WegianWarrior (talk) 18:12, 19 June 2018 (UTC)[reply]

Here's a 747 refueling in-flight: [18] —2606:A000:1126:4CA:0:98F2:CFF6:1782 (talk) 21:59, 19 June 2018 (UTC)[reply]

Might that be Air Force One? ←Baseball Bugs ^{What's up, Doc?} carrots→ 22:10, 19 June 2018 (UTC)[reply]

There's a doghouse, so that's a NEACP, not the Trump Tourbus. Some other civilian aircraft in long-duration military service (such as covert ELINT) have been fitted for refuelling too. The current Airforce One was built as a Boeing VC-25, the designed-in Airforce One variant, but the new Airforce Ones are to be recycled from bankrupt Russian oligarchs (seems appropriate), so will require conversion.

Outside the US, there are also Airbus variants, such as the A330 Multi-Role Tanker Transport, which can offer both refuelling supply and consumption. So if you're writing a Dan Brown novel, it's off-the-shelf parts. Andy Dingley (talk) 23:33, 19 June 2018 (UTC)[reply]

Unrelated question: At Aviation fuel what does this mean: "Aircraft have a high peak power and thus fuel demand during take-off and landing"? Does that mean that a disproportionate amount of fuel is consumed "during take-off and landing" relative to the rate of fuel consumption at cruising speed and cruising altitude? Bus stop (talk) 23:07, 19 June 2018 (UTC)[reply]

Not so much "take off" itself, but the climb to altitude. This is why many military mission profiles involve refuelling very soon after take-off - the aircraft can take off and climb in a much lighter state. Andy Dingley (talk) 23:23, 19 June 2018 (UTC)[reply]

"disproportionate amount at take off?" It seems so. According to https://answers.yahoo.com/question/index?qid=20060813151514AAVe8Ms&guccounter=1 a Jumbo Jet consumes 1 gallon per second at cruising regime and 8 gallons per second at take off and climbing. Somewere else it talked of three tons in the first three minutes and eight tons per hour cruising. 194.174.76.21 (talk) 09:54, 20 June 2018 (UTC) Marco Pagliero Berlin[reply]

Among other things, you're using a richer mixture at those times. It's vaguely like with a car: you use less fuel when you're cruise-controlling down a straight and flat highway than when you're climbing a hill and accelerating from a stop. Cars don't use much fuel when descending hills, but they don't have to worry about maintaining power in order to avoid stalling too soon and falling out of the sky too fast; the aircraft has to maintain lift until it's ready to stall over the runway, so lots of power has to be used. Nyttend (talk) 00:22, 20 June 2018 (UTC)[reply]

Thanks everybody. That is interesting. And I guess the fighter plane has a much further distance on its itinerary than the tanker plane, and that one tanker plane refuels many fighter planes. Bus stop (talk) 01:14, 20 June 2018 (UTC)[reply]

Fighters have to be fast and maneuverable, so they can't carry enough fuel relative to their empty weight to provide a long range as well. --76.69.118.94 (talk) 08:36, 20 June 2018 (UTC)[reply]

June 20

Trumpeter Swan question

Ok, this is kind of a weird one. I was kayaking on one of our local lakes just now and saw that Trumpeter Swans were again present there. They used to only come by during migration but the last few years there has been a pair of them summering there. As I paddled around I came upon what had to be their nest. It was two vegetation-covered rotting logs in shallow water, with lots and lots of shiny white feathers scattered all over. They looked more or less like one expects from a waterfowl nest except for one thing: the poop. I declined to take a picture as I assume words will suffice here. Normally bird excrement is a runny, whitish sort of thing. These two nesting areas each had at the outer corner a pile of very solid turds, as one would expect from a dog or a human. I can’t find anything in our article on these birds about this, but it seems highly unusual to me. Beeblebrox (talk) 01:11, 20 June 2018 (UTC)[reply]

Are you asking "what do their feces look like"? Can't speak directly to swans, but if you've ever seen Branta canadensis feces, you'll remember that they're nowhere close to runny or whitish; it's one of the biggest reasons large populations of them are often considered pests in the lower 48. Nyttend (talk) 01:41, 20 June 2018 (UTC)[reply]

I used a well known search engine to find images of 'swan faeces' and it provided a few which showed large solid cylindrical motions. For what it's worth it also showed motions from geese and chickens which are solid and shaped, so by no means are all bird faeces liquid. Having kept finches for a while my experience was that liquid faeces usually indicated a digestive problem. Richard Avery (talk) 07:32, 20 June 2018 (UTC)[reply]

How to figure out the most energy-efficient way to eat food in an industrialized country?

Corn, wheat, soybeans, cotton, and hay account for 90% of harvested acreage in the United States. Corn, wheat, and soybeans are grown for both animal feed and human consumption. Per 100 grams, cooked yellow corn yields 96 calories. Wheat cannot be eaten directly. It can be turned into bread, noodles, and other wheat-based products, but who has the time to let the bread rise? Home-made bread may be eaten on occasion, but making bread everyday may be tiresome. Also, the inexperienced person who has zero cooking skills may not know how to knead dough. I suppose one can buy dried soybeans and make soymilk, but that's mostly liquid. The okara of the soybeans may be used to make less-filling dishes. Per 100 grams, Russet potatoes yield 97 calories. Per 100 grams, cooked black beans yield 132 calories. Per 100 grams, cooked white rice yields 130 calories. So, judging solely by energy content per weight, cooked black beans and cooked white rice win. However, what about the amount of energy that goes into producing the food or the amount of energy that goes into transporting food from the farm to the supermarket? By taking all things into account, which food would be most economical for a random person in, say, New York City? SSS (talk) 02:38, 20 June 2018 (UTC)[reply]

This is why McDonald's was invented. ←Baseball Bugs ^{What's up, Doc?} carrots→ 03:31, 20 June 2018 (UTC)[reply]

There are many additional variables here. Take wheat and bread. It is more energy-efficient to make bread in a bakery than at home. This has been true since ancient times. Or look a soy beans in the US: almost all (more than 90%) of the beans and the oil are shipped to China for use as animal feed there. One crude measure of the pre-consumer energy cost is the price per calorie. This works better than you might expect, because it accounts for the energy cost of all of the inputs, including things like marketing, where the money goes to pay the salaries of people who use energy. It does not account for "free" inputs like un-captured environmental costs. You then need to add the consumer's preparation costs and the costs of post-consumer waste handling. -Arch dude (talk) 05:02, 20 June 2018 (UTC)[reply]

As an aside, use a no-knead recipe for home made bread. http://www.snk.com.au/html/s01_home/home.asp Makes very good bread. Not, perhaps the best I've ever had, but better than all but the best, and of course we fine tune the recipes to taste, lots of caroway in the dark rye bread for example.Greglocock (talk) 05:50, 20 June 2018 (UTC)[reply]

Check out Soylent (meal replacement). Eat it for a week and then watch the movie Soylent Green. --Kharon (talk) 06:15, 20 June 2018 (UTC)[reply]

"Soylent Green is ... a brand of meal replacement products !?" Gandalf61 (talk) 08:47, 20 June 2018 (UTC)[reply]