Wikipedia:Reference desk/Archives/Science/2016 September 3

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September 3

XYY syndrome heredity

Why can't this syndrome be inherited? 24.255.17.182 (talk) 00:43, 3 September 2016 (UTC)

Because its mechanism of action does not warrant it. This is due to a chromosome separation, just another one of nature's possible hiccups. This type of incident is not caused by a father's genetic predisposition and therefore can effect any reproducing human male. 199.19.248.107 (talk) 03:38, 3 September 2016 (UTC)

What happens in meiosis from a trisomic parent cell? —Tamfang (talk) 08:15, 3 September 2016 (UTC)

It's not entirely clear. Typically the two Y chromosomes line up during segregation as if they are going to enter one daughter cell, and the X chromosome to another, but you don't actually see a high number of XYY sons of XYY fathers. It seems that the extra Y chromosome is simply lost at some point, for unknown reasons, thus preventing heredity of the syndrome [1]. My source is from 2000, so maybe something else has been discovered more recently. Someguy1221 (talk) 09:26, 3 September 2016 (UTC)

Meiosis is extremely complicated, and basically needs a full two years of college biology to comprehend; I would not pretend to understand it in one semester. You really have to take Genetics 301 and 302, as well as Bio 101 & 102 (and ideally Organic Chem 201 & 202) to comprehend it. You are looking at not just the mere replication of chromosomes, but at their conjunction by pair, and crossing over. This becomes quite complicated with normal, not even to mention abnormal sex chromosomes, for which 'start with meiosis. μηδείς (talk) 07:07, 5 September 2016 (UTC)

classification of science

I am struck with science, please help me to come out. I do not know how to make an ordered flow chat of disciplines of science. In your branches of science article the disciplines are defined but not ordered. For example, In that article geography, oceanography are explained separately but there is nothing mentioned that oceanography comes under physical geography. Off course, the oceanography is the branch of earth science, but for order and mind map consideration it should comes under physical geography. I am confusing with disciplines, so please create and put an ordered flow chat for science(hierarchical classification system). Like this, EARTH SCIENCE>GEOGRAPHY>PHYSICAL GEOGRAPHY>OCEANOGRAPHY. If, I mentioned anything wrong excuse meELANCHERAN (talk) 11:31, 3 September 2016 (UTC)03/09/2016.

We have articles on Branches of science and there is a cross-reference summary here, but perhaps someone else can find a better classification. Dbfirs 12:17, 3 September 2016 (UTC)

All classification systems are inherently arbitrary and can never be fully self-consistent. There's a book I recently became aware of, which I intend to read soon, that may help the OP understand the nature of their problem. Everything is Miscellaneous. I've not read it myself yet, but it looks interesting.--Jayron32 13:39, 3 September 2016 (UTC)

Outline of natural science looks very good. Loraof (talk) 14:55, 3 September 2016 (UTC)

Your problem is that a subject such as oceanography is an amalgam of various scientific disciplines all of which have some application to the study of the oceans - geography, geology, hydrology, meteorology, biology, ecology, chemistry, physics, astronomy - and probably others as well. That will apply to many fields of scientific research: in most cases there is no simple linear classification, but a web of interconnecting topics. Wymspen (talk) 15:14, 3 September 2016 (UTC)

Smallpox vaccination

What percentage of the world's population was vaccinated against smallpox prior to it's eradication? — Preceding unsigned comment added by 169.244.148.235 (talk) 13:59, 3 September 2016 (UTC)

According to Smallpox vaccine, the ones inoculated were the ones in areas of outbreaks. So it would seem that not everyone was vaccinated, just the ones who seemed at risk. ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:28, 3 September 2016 (UTC)

I was, in the 60's, if that helps. And there were no outbreaks of the disease in NYC at the time of which I am aware... Same Bat Time, Same Bat Channel, Where No Man Had Gone Before! μηδείς (talk) 23:36, 3 September 2016 (UTC)

And everyone who applied for a US passport. (Fun fact: I got the jab at least twice, but lack the usual scar; that may be because Mom got it while hosting proto-me.) —Tamfang (talk) 08:34, 4 September 2016 (UTC)

I don't have the scar either, but my mom said that was due to a difference in how it was administered. That's OR, of course. But she saw what happened both times. I suspect it may have had to do with mass injections early on, where everyone got a pressure-powered blast from needles which were sterilized, but not replaced, somewhat like the swine-flu panic of the 70's. I was just a kid, so someone with knowledge will have to comment. μηδείς (talk) 20:34, 4 September 2016 (UTC)

• Yes, I confirmed this with my mother. She got four scarring scratches in the 50's which left scars as soon as the innoculation for the lethal infection was available, and we got one injection over a decacade later once it was merely highly infectious; my third sister. borne in 74' did not even get the shot, as it was considered defunct. μηδείς (talk) 01:28, 5 September 2016 (UTC)

Ah. This is really interesting! Normally, if one gets a inoculation against small-pox or even TB, a reaction doesn’t show at the inoculation site if one already has an antibody immunity. As Tamfang suggests (my interpretation and not theirs alone by the way): “If one is born with the parental antibodies, then the reaction at the inoculation site doesn’t happen”. So the statement that μηδείς's mother had several scarring surprised me. One inoculation should be enough for small-pox. So I think that her mother was concatenating other inoculations as well. Would she agree? P.S. It is no good at looking at your mom's arms for confirmation. I have just had my shirt off to look for my scares and they have all but nearly faded away. I should think that an Egyptian mummy is in better preservation than myself on that score. --Aspro (talk) 20:43, 5 September 2016 (UTC)

Submarine propulsion

The Baleen whale feeding only on widely available Krill and Plankton can travel great distances underwater and has enough surplus energy to lunge its huge mass above the sea. Can a submarine be made to use the same energy sources? AllBestFaith (talk) 19:18, 3 September 2016 (UTC)

No, because the equipment needed to produce biofuel is too cumbersome and inefficient for submarine propulsion. 2601:646:8E01:7E0B:F88D:DE34:7772:8E5B (talk) 21:20, 3 September 2016 (UTC)

Just like you wouldn't make a whale drink petroleum in hopes of making it swim faster. ←Baseball Bugs ^{What's up, Doc?} carrots→ 21:26, 3 September 2016 (UTC)

Krill-Widely available yes. Locally dense yes. Available where a submarine needs to go, probably not,reliably. You still have to turn shrimps into fuel, which is non trivial in the context of a small ship. Greglocock (talk) 02:01, 4 September 2016 (UTC)

And also there's the inconvenient fact that even the smallest submarine is much bigger than the biggest whale, so its energy demand is correspondingly bigger. 2601:646:8E01:7E0B:F88D:DE34:7772:8E5B (talk) 06:17, 4 September 2016 (UTC)

Huh? AllBestFaith (talk) 14:31, 4 September 2016 (UTC)

What I wanted to say ;-). Also Kaiten. --Stephan Schulz (talk) 15:14, 4 September 2016 (UTC)

There certainly are smaller submarines, such as DSV Alvin. StuRat (talk) 15:44, 4 September 2016 (UTC)

Let's look at what would need to be done to use plankton as fuel. I see two possible ways:

1) Dry it out and then burn it. The drying would need to take place someplace off the ship, and if you don't want to use a lot of energy drying it, you would need to spread it out in a dessert (where the stink wouldn't bother many people). Then there's the energy used to catch the plankton, transport it to the dessert, spread it out, collect it, and deliver it to the sub. Then you would need oxygen to burn it and would vent smoke, and dump ash, so the sub would need to be in schnorkel range of the surface and would lose any stealth. Not very practical.

2) Some type of fermentation, with the right bacteria, could produce a film of oil on the vats containing it. This oil could be burnt to drive the submarine. You would only get a small amount of oil out of a vast amount of plankton, and only after a long time, so again it wouldn't be a practical fuel source onboard. The fermentation could again take place elsewhere and the oil be delivered to the sub, but this would have the same disadvantages of needing oxygen, producing smoke, and requiring constant resupply, although you wouldn't need to dump ash. This isn't very practical now, but if you had non-nuclear subs and were cut off from petroleum supplies, say during a war, then this or some other form of biodiesel might make sense. I believe the US Air Force has a synthetic jet fuel program, for a similar case where access to refined petroleum might be cut off during a war. So, it's not completely out of the question. StuRat (talk) 15:57, 4 September 2016 (UTC)

Mandatory link. Tevildo (talk) 16:58, 4 September 2016 (UTC)

• There is research on "plankton fuel cells", e.g. here or just google for more.47.192.157.95 (talk) 16:59, 4 September 2016 (UTC)

My very quick back of the envelope calculations, a blue whale produces about 75kW. Based on a 1.5 million kCal per day diet. A nuclear sub produces a hundred to "hundreds" of MEGAWATTS, that's several orders of magnitude off. Vespine (talk) 02:55, 5 September 2016 (UTC)

Perhaps we can put little harnesses all over the sides of the sub in multiple layers, and the military can use a mind control ray of some sort to make the krill take their rowing positions and move the submarine around with great stealth... :) Really though, I think the biggest issue is that the military wants as much power as they can get, and given the availability of nuclear submarines I don't think they want any hippie-dippie green sustainable power within torpedo range of their boat, which I imagine is quite some distance. Wnt (talk) 13:25, 5 September 2016 (UTC)

Sure, in principle. But current technology is not going to match a whale for performance, as you probably know (I don't think anything humans build can match an animal for overall efficiency and performance, but that's a separate issue).

For reference, see Anaerobic_digestion#Power_generation, Biogas, Sustainable_energy#Biomass. Artificial_muscle may also be of interest, because whales' stroke pattern is a lot more efficient than a silly propeller. Waterjets can be even more efficient, but only for small critters, due to stuff about reynold's numbers. See Cephalopod#Locomotion_and_buoyancy for claims and ref. RoboTuna was one early project that attempted to replicate the vortex kicking utilized by many aquatic animals. SemanticMantis (talk) 15:39, 5 September 2016 (UTC)

Whales are more efficient at locomotion, but subs may have the edge in efficient communication (with others of the same kind) and definitely have better efficiency when idle, when a sub doesn't need to use any energy at all. StuRat (talk) 18:02, 6 September 2016 (UTC)