Wikipedia:Reference desk/Archives/Science/2018 March 7

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March 7[edit]

A case study of a male with anorexia nervosa and low testosterone levels.[edit]

Could anyone help me find the full text of this pubmed article? Thanks for your time and help! 60.54.122.164 (talk) 08:12, 7 March 2018 (UTC)[reply]

  • If you really need a copy of a scientific article and don't want to pay for it, shoot the main author an email and ssk for a "reprint". But for something that old, you may have to go to a nearby university library and look on microfiche. Abductive (reasoning) 09:18, 7 March 2018 (UTC)[reply]
  • There's a Wikipedia project called Wikipedia:WikiProject Resource Exchange/Resource Request that lets you ask other Wikipedians for copies of references they may have access to but you don't. I would try there. --Jayron32 13:26, 7 March 2018 (UTC)[reply]
Imagine the temerity of coming to the reference desk looking for a reference! Matt Deres (talk) 14:53, 7 March 2018 (UTC) [reply]
I think Abductive is right that the big problem here is it possibly just isn't online. The Journals own archives only go back to 1996 [1]. I had a look at it doesn't look like Jstor has archives and I couldn't find anyone else with them. I looked at the University of Auckland database, obviously not the most extensive in the world although they do have a medical school, and they only seem to have the official journal (including archives back to 1996) for online access. Further back to 1978 you will need to get access to the printed journal. Or make an interloan request. So unless someone has specifically made this particular article available, someone is going to need to scan or digitally photograph some physical version of the original journal. Nil Einne (talk) 01:21, 8 March 2018 (UTC)[reply]

Does the crust thickening over the eons make it easier or harder to break Earth's highest natural point above sea level record?[edit]

The Himalayas are too still growing to attempt the record but times when the world's highest point stops rising happen eventually.

2. Are the highest points in Himalaya-style ranges on Pangeas? Sea level is lower then, colliding plates are bigger and more numerous, providing more chances for a mountain to beat the others but Pangeas stop rising when mantle convection switches direction due to continent insulation instead of waiting for the limits of structural strength or plate power so I'm not sure.

3. Or are they/will they be volcanos? Couldn't a shield volcano significantly exceed Mauna Kea volume by having it's plate decelerate and reverse direction a few miles after the hotspot passed? Sagittarian Milky Way (talk) 23:17, 7 March 2018 (UTC)[reply]

To answer 3: Olympus Mons is a Shield volcano on Mars. With its 22 Km height its 2 and a 1/2 times higher than our Mount Everest. In fact most "peaks" on planets and moons in our system are volcanos and given their measure we are probably very lucky on earth, which is roughly twice as big as Mars, not to have a relative copy of Olympus Mons with 44 Km height on earth. --Kharon (talk) 02:02, 8 March 2018 (UTC)[reply]
Given that Mars gravity is lower than Earth, my intuition would be that the maximum height for a shield volcano given broadly equivalent tectonic conditions would be lower on Earth than on Mars, but I can't currently find anything to substantiate this. Some tangentially relevant information here: [2] and here: [3], the latter of which makes the point that the volcanoes on Mars are so large due to the lack of plate tectonics (Earth has more active volcanoes, but the magma plumes move relative to the cone, so the overall cone size is limited. Volcanoes on Mars erupted more slowly but for longer in the same place.) MChesterMC (talk) 16:11, 12 March 2018 (UTC)[reply]
The highest points are probably under control by glacial erosion. If land gets too high on Earth it will get covered in glaciers, and icecaps, which will grind off the surface rapidly. Some rapidly rising tectonic areas on Earth are under deep river valleys. see River anticlines. Graeme Bartlett (talk) 03:30, 8 March 2018 (UTC)[reply]
So a Greenhouse Earth might have the highest point of at least the Phanerozoic if higher snowline overcomes the higher sea level? Sagittarian Milky Way (talk) 03:55, 8 March 2018 (UTC)[reply]
Yes. Greenhouse conditions will also have more humidity and then condense more on high areas. The monsoon may be heavier with more erosion. This may trigger more uplift adjacent to the big rivers. But also the snow line would then be higher. But if the temperature is so high, as on Venus, there is no condensation of water to liquid or solid, even though it has a similar amount of water vapour as the Earth's atmosphere. This idea would predict tropical areas to have higher topography than polar regions. Graeme Bartlett (talk) 04:24, 8 March 2018 (UTC)[reply]


Most of the earth's highest points are tectonic rather than volcanic in origin, although these are almost all in Asia. The highest active volcano in the world is Ojos del Salado on the borders of Chile and Argentina at 6,893 m, about 2,000 m lower than Everest. The continental collision between the Indian and Eurasian Plates that has produced the Himalayas is not that unusual in Earth's past history, but it would be useless to speculate if the mountains associated with say the Caledonian orogeny were higher - we simply cannot know. Mikenorton (talk) 10:28, 8 March 2018 (UTC)[reply]
So if anyone says the Appalachians or whatever were 30,000 or 33,000 feet that's just unfounded speculation? Sagittarian Milky Way (talk) 10:46, 8 March 2018 (UTC)[reply]
That would be a guess, albeit an educated one no doubt, but insufficient to answer this question in my opinion. Our best guess for the Caledonides is that they were similar in scale to the Himalayas - that's all we can say. Mikenorton (talk) 11:25, 8 March 2018 (UTC)[reply]