Wikipedia:Reference desk/Archives/Science/2017 February 22
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February 22
editHow long does it take before a volcanic island can support trees?
editI remember at some point I learned that since volcanic islands start barren, it takes a while before it develops enough top soil to support large plants like trees. Gradually, algae will build up on the rocks, then lichens and mosses, eventually building up and dying enough to lay the foundations for grasses shrubs and trees.
I've become suddenly curious about this and I was wondering if anyone had any information on how long this can take? — Preceding unsigned comment added by 184.148.114.163 (talk) 05:24, 22 February 2017 (UTC)
- What type of volcanic rock is the island made from? How far is it from other land? What is the local climate? There are too many variables to give a clear answer. A tropical island may have coconut palms quite quickly - but it will take a very long time for Surtsey to turn into forest, given how few trees grow in Iceland anyway. Wymspen (talk) 08:48, 22 February 2017 (UTC)
- Trees can grow without soil. A seed in a crack in a rock will germinate if it has fresh water. Here is one I photographed in Scotland.--Shantavira|feed me 09:22, 22 February 2017 (UTC)
- I'd expect there to be relatively few volcanic island developments in fresh water though. If they're developing as new island material, that's going to be in the sea. Andy Dingley (talk) 09:54, 22 February 2017 (UTC)
- Trees can grow without soil. A seed in a crack in a rock will germinate if it has fresh water. Here is one I photographed in Scotland.--Shantavira|feed me 09:22, 22 February 2017 (UTC)
- Depends a lot on the bird population. Some plants can grow without soil, provided that there are minerals available from either seaweed (which is a very large algae from a very small attachment) or guano. If the island is near enough to other established islands that birds can occupy it, then plants can follow quite rapidly, without needing to wait for a soil layer to be generated. Andy Dingley (talk) 09:54, 22 February 2017 (UTC)
- Our article on the island of Surtsey describes how plant life built up on a new volcanic island.--Phil Holmes (talk) 09:58, 22 February 2017 (UTC)
- The general process by which living things will populate a new land, or change over time, is called Ecological succession and our article on the subject will provide a good starting point for your research. Especially if you follow links to more detailed articles. --Jayron32 13:23, 22 February 2017 (UTC)
- Some islands never acquire trees naturally, the Falkland Islands or the Faroe Islands for example. There needs to be a mechanism which allows seeds of the right species to gain a foothold. Birch trees will happily colonise apparently barren slate mine tips [1] but are wind blown and not carried around by birds. Alansplodge (talk) 13:47, 22 February 2017 (UTC)
- Here's [2] a nice research article that has studied primary succession in NZ. They are not talking about a small volcanic island, but it's got good discussion of the processes involved and time scales. The first 10 references also comprise a nice bibliography on the subject of primary succession. SemanticMantis (talk) 15:01, 22 February 2017 (UTC)
- The biology section of our article Surtsey will be of interest. Surtsey is a volcanic island formed in the 1960s, and according to that article Salix phylicifolia was found there by 1998. DuncanHill (talk) 16:42, 22 February 2017 (UTC) Which contains the immortal words "An improperly handled human defecation..." DuncanHill (talk) 16:49, 22 February 2017 (UTC)
- Bear in mind though that neighbouring Iceland has only three native "forest-forming" tree species, the downy birch, rowan which is rare and aspen found in only six locations. [3] Alansplodge (talk) 17:53, 22 February 2017 (UTC)
- Other articles of relevance include Colonisation (biology) (a bit stubby, alas), and Insular biogeography. DuncanHill (talk) 16:49, 22 February 2017 (UTC)
- The article was already linked to by by Phil Holmes above. Nil Einne (talk) 20:36, 22 February 2017 (UTC)
- So it was! I hadn't read all the answers before I answered. DuncanHill (talk) 01:55, 23 February 2017 (UTC)
- Having a caldera above sea level would tend to speed up the process, as fresh water from rain, fertilizer from birds, and sand grains eroded from the peak could collect there. On the other hand, islands in the polar regions may never grow trees (or at least not until the Earth's climate changes significantly). See tree line. StuRat (talk) 19:00, 22 February 2017 (UTC)
A point where something can be a liquid, gas and solid at the same time
editI read an article here a month or two ago but can't remember where it is. The gist of the article is that at a certain temperature and at a certain pressure water (for example) can be liquid, ice and vapor all at the same time. I can't remember the term and hope I did not misread the article. I believe the term started with a "t" 198.72.29.37 (talk) 16:33, 22 February 2017 (UTC)
- Since the OP brought up water, a bit of trivia. The original definition of the Celsius scale set 0°C as the freezing point of water at atmospheric pressure. The modern definition of the Kelvin scale uses the triple point of water, which is almost at 0°C but at a much lower pressure. Those are not the same temperature; it only turns out that for water (and this is quite a unique case) the liquid-solid separation in the phase diagram is almost vertical, so temperature of freezing water is almost the same at the triple point pressure and at atmospheric pressure. TigraanClick here to contact me 17:08, 22 February 2017 (UTC)
- Clarification: the triple point is not defined so that it becomes the new 0°C. Rather, the triple point is defined as 273.16 K, and temperature in degrees Celsius is defined as temperature in kelvins minus 273.15, which makes the triple point exactly 0.01°C. See the SI standard, section 2.1.1.5. --76.71.6.254 (talk) 18:33, 22 February 2017 (UTC)
- Note that, as mentioned in the first sentence of our triple point article, that's where the 3 states coexist in "thermodynamic equilibrium". It's also possible to have all 3 states exist, but not at equilibrium, at other pressures and temps. For example, at the melting temp of ice, you will have ice and water but also some water vapor, in the form of humidity. StuRat (talk) 18:41, 22 February 2017 (UTC)
- Around this time of year, in Minnesota for example, the ice on the frozen lakes starts to melt and that meltwater starts to evaporate. So a given lake is solid, liquid and gas at the same time. ←Baseball Bugs What's up, Doc? carrots→ 15:20, 23 February 2017 (UTC)
"Designer" benzodiazepine vs "legitimate" ones
editWhilst speaking to a psych nurse friend of mine, she told me about dealing with overdoses of Phenazepam, a Soviet-designed benzodiazepine. The article on it led me to an area I'd never known before - List of benzodiazepine designer drugs. I'd never heard of a "designer benzo" before, and the concept intrigues me.
What do these "designer" benzos do in terms of pleasure-inducing effects, which the "legitimate" ones manufactured by big pharma do not?
As far as I'm aware, one of the highest-in-demand benzos on the street is Alprazolam, and it definitely comes from big pharma, not an illicit lab. Here in Australia, it was re-scheduled to make prescribing rules stricter for precisely this reason.
So my question is twofold:
1. Do any of these "designer benzos" work any better in terms of what a drug abuser would want, versus those variants manufactured by legitimate pharma? I understand that "legitimate" benzos are heavily regulated too, I'm just wondering why someone who wanted a "high" would want a "designer" benzo, as opposed to illicitly obtaining a "pharmaceutical" one? - Is there an "ease of manufacture" issue? Or are they actually any more "pleasure effective"? And if the latter, how so?
2. Where in the world is most of this stuff manufactured? I'd never encountered the idea of an illicit benzo drug manufacturer before. Even though Alprazolam may, gram for gram, be worth more than heroin on the street (it's more potent), the route I had known of almost always involved diversion from a "legitimate" source. Not hard at all in many countries with weak law enforcement, and quite possible even in first-world ones - rumours of "dodgy pharmacists" and "naive doctors" abound, or you just go Doctor shopping. And Darknet markets are choc-a-block with "legit-manufactured" stuff of this sort. Not illicit manufacture. So, where in the world are these labs? What keeps them financially viable, when "legitimate diversion" exists as an alternative? And how hard is it to set up a benzo manufacturing facility? (I assume it's a lot more difficult than a methamphetamine lab?).
Please note, I have ZERO intention of taking any benzo, other than one prescribed to me legitimately by a doctor, or dispensed to me by a hospital. So I can't see this as remotely "medical advice". I'm just intrigued by a new side to the "illicit" market I never knew about, and trying to understand how it operates, and what sustains it. Eliyohub (talk) 18:52, 22 February 2017 (UTC)
- Benzodiazepines, desiner or not produce their effect by attaching to receptors in the brain. They all have different affinity, that is the ability to activate those receptors. Therapeutically speaking each of them has a potency characteristic, drugs with high potency require small milligrams or even fraction thereof to produce therapeutic effect, others have low potency and are usually prescribed with high milligrams (5-10-25). I don't think there is a principle difference between them otherwise. It is better to avoid using them because they all develop tolerance which leads to the need for a user to take higher and higher dose. Multiple problems will then develop, dependency, etc. Talk to your doctor before using any chemical but the table salt :-) --AboutFace 22 (talk) 22:02, 22 February 2017 (UTC)
- I said that - any benzos I use are prescribed by a psychiatrist, and I assume he knows what he's doing. And in my experience, pharmacists tend to be savvy too. When I turned up with a prescription from a different doctor than my previous prescription, he asked me why. I explained (my main doctor was away, he knew who would be filling in for me) and invited him to notify both of them, they'd already be aware of it. But it showed that eyes are watching! Eliyohub (talk) 23:37, 22 February 2017 (UTC)
- First, there's our article List of benzodiazepines, which lists them all, licit, illicit, and off in the shadows somehwere. It's worth mentioning that approval for medical use varies widely by country. Also drugs a physician can't prescribe here are probably either explicitly covered by the US Federal Controlled Substances Act (even banned if someone put them in the infamous "Schedule I"), or by one of its codicils banning "analogues" of controlled substances like benzodiazepines. For example, the "Backdoor Pharmacist" mentions three designer benzos, two of which only differ from existing, approved, US controlled substances by a functional group added on. (This is actually a common practice in Big Pharma - take a competitor's highly profitable drug, slap a methyl or hydroxyl group on its structure, and see if you have the next new leader in that market, or something too poisonous, unpleasant in its adverse effects, inert or expensive to sell).
- And that's the story with almost all the designer benzodiazepines - they didn't make the cut for one reason or another, or they'd be "approved, regulated benzodiazepines", and the US Federal government explicitly bans most or all of them for being one functional group away from something they already regulate.
- A short 2015 article in the journal World Psychiatry, "Designer benzodiazepines: A new challenge", Bjoern Moosmann, Leslie A King, and Volker Auwärter covers everything you were asking about in part 1 of your question. It's not a simple set of answers - the benzodiazepine family differs greatly, even among drugs which have been tested and are approved for medical use worldwide. Some have, at the prescribed dose, a calming, "anxiolytic" effect. Some, like Versed (midazolam) are strong enough they cause patients to remain calm during surgical or endoscopic procedures, and cause amnesia of events during those procedures. Each member of the benzodiazepine family has its own unique combination of effects on the taker's consciousness and mood.
- Since, according to Moosmann et al, none of the "designer" benzos they mention, diclazepam, flubromazepam, pyrazolam, clonazolam, deschloroetizolam, flubromazolam, nifoxipam and meclonazepam have been approved for medical use in any country, the testing needed to show what they do to the people who take them is largely not available. Almost all of them were developed by drug companies and papers were published on them by their developers/discoverers, but it's a safe bet that a drug candidate that doesn't get as far as Phase III clinical studies just wasn't likely to be approved by the medical regulatory community for one of a number of reasons - usually toxicity, lack of a good therapeutic index (you get bad side effects at or just above the dose that does you any good), or lack of efficacy.
- There's also unprofitability Let's say one of these drugs is so close to (for example) diazepam in its tox profile, therapeutic index, cost of manufacture and general effectiveness that it's a "me too" drug for a generic medication that sells for a few cents a tablet - you won't make your money back testing it in lots of patients and filing for regulatory agency approval. But we don't even know that about any "designer benzodiazepine" - just that in an industry addicted to the almighty (national currency of your choice), these chemicals were never put on the market.
- So, there's a huge flashing neon sign in Gothic script over designer benzodiazepines - Noli me Tangere ("Don't fool with me"). You're dealing with potent central nervous system depressants whose only point in common is that they're either too highly toxic, too expensive to make or get approved, or too unpredictable in their effects to be used recreationally. loupgarous (talk) 22:43, 22 February 2017 (UTC)
- Thanks, that helps somewhat. But even reading that article, I'm still lacking any understanding if there's any "designer benzo" which a drug abuser has shown they prefer over an "approved" equivalent? I assume human testing of this sort would be risky and ethically dubious. But has anyone surveyed the users of these drugs, and had them say they found some effect these "illegal" ones do, over what a "legal" one can? As I said, Alprazolam remains amongst the top choices in the black market, and it is most definitely "approved"! So I still await any surveys or studies on those who admit to using these drugs, and hear significant numbers of them say "this (designer benzo) does something for me which (the closest "approved" alternative) couldn't"?
- The question about unprofitability would also work the other way - why would anyone pay for illicit manufactured, untested stuff, when diversion of stuff from a proper factory is so easy and widespread? How does the "illicit manufacture" market compete with the "illicit diversion from legal" market?
- Also, any data on manufacturing on this stuff, and where it originates from? And how tough it is to set up a manufacturing facility? I have no idea what's involved in benzo synthesis. Eliyohub (talk) 23:31, 22 February 2017 (UTC)
- Eliyohub, did you read the review of the "Backdoor Pharmacist"? The author does, actually, give some indication of three designer benzodiazepines' appeal in the illicit drug culture. That the review was largely negative doesn't mean that someone didn't like them, but that they may be a little more intelligent than to write about it to an Internet site that might capture their IP address. In that respect, I can't help you, because I don't play on the dark Net.
- Nor can I say why anyone would eat stuff someone made in their bathtub after so many folks who thought they were getting fentanyl wound up dying after one last trip on 3-methylfentanyl, and a similar number of people wound up with Parkinson's disease because they thought they were getting designer Demerol and wound up with some MPTP as an added ingredient. I'll have to defer to actual illicit drug users for the answers to those questions. Good luck! loupgarous (talk) 02:32, 23 February 2017 (UTC)
- The best benzodiazepine is aerobic exercise, it produces endorphins, they are close to the benzos chemically, are attached to the same receptors and have similar therapeutic effects. The exercise, although not for everyone, produces other benefits too. --AboutFace 22 (talk) 01:41, 23 February 2017 (UTC)
- That's not correct. Endorphins are opiates. Opiates and benzodiazepines both reduce anxiety, but in terms of chemistry and receptor mechanisms they have virtually nothing in common. Looie496 (talk) 13:57, 23 February 2017 (UTC)
- @Looie496, you are correct. Sorry for the error. --AboutFace 22 (talk) 16:11, 23 February 2017 (UTC)
- Eliyohub, you may be interested (even though they deal with different designer drug families than the benzodiazepines) in the books of American designer drug chemist Sasha Shulgin, who synthesized 179 different psychedelic phenethamine compounds, documenting his psychonaut experience (both the syntheses of the drugs, and the way they made him and his friends feel) in Phenethamines I Have Known and Loved. Dr. Shulgin got away with making these designer drugs partly because he worked for the US Drug Enforcement Administration in his spare time testifying as an expert witness, and had a DEA license to make the drugs. The DEA asked him to turn his license in after they raided his home laboratory, an impressive installation with its own nuclear magnetic resonance spectrometer for analyzing his product. Dr. Shulgin's books Phenethamines I Have Known and Loved and Tryptamines I Have Known and Loved are unique in that they document extensively both the scientific side of designer drug design and synthesis and the subjective sensations these drugs created in Dr. Shulgin and other volunteer test subjects. loupgarous (talk) 21:37, 23 February 2017 (UTC)
Is there a part of North America that can grow all common and semi-common English plants without crippling them?
editBut with little to no human help – otherwise you could grow cactus in Antarctica. Absolutely no weather amelioration (like greenhouses, watering or frost covers). Shade/full sun and whatnot plants would only have to grow in some light regime to not disqualify a part of North America, water hungry plants like willows would only have to grow near water and lilly pad-type things would only have to grow in water. Sagittarian Milky Way (talk) 22:58, 22 February 2017 (UTC)
- The Pacific Northwest of the US and into Canada has a climate similar to England, and the climate can be varied by moving closer to, or farther from, the coast and further up or down the mountains. However, they may be out-competed by native plants, lack pollinators specific to those plants, and suffer from native plant parasites. With those problems in mind, the answer is likely no. StuRat (talk) 23:05, 22 February 2017 (UTC)
- There's no bees in the Pacific Northwest? Did English colonists have difficulties replicating their gardens in the PNW, Massachusetts, New York, PA, MD, or Virginia? Sagittarian Milky Way (talk) 23:28, 22 February 2017 (UTC)
- No problem at all. The early English colonists only had to poke a artists paint brush in to the male sexual organs of a flower and deposit the pollen into the female sexual organs. Just like what bees do.--Aspro (talk) 00:34, 23 February 2017 (UTC)
- The hardiness zone of the Boston area in the Little Ice Age must've been a problem for something. Sagittarian Milky Way (talk) 01:22, 23 February 2017 (UTC)
- Oh wow. Wikipedia even has an article... as always! Hand-pollination.--Aspro (talk) 00:47, 23 February 2017 (UTC)
- And then the colonists got lazy and imported the European honeybee. Sagittarian Milky Way (talk) 01:14, 23 February 2017 (UTC)
- Some flowers are designed to exclude all but one specific pollinator. Here's an interesting example of this: [4]. StuRat (talk) 01:03, 23 February 2017 (UTC)
- There isn't even a part of England that can grow all common and semi-common English plants without crippling them. The vegetation of the Essex fens is very different from the vegetation of the Yorkshire moors, both of which are very different from the vegetation of the New Forest. Looie496 (talk) 13:53, 23 February 2017 (UTC)
- I didn't find an answer, but this article about the difference between British and US gardening culture is quite interesting. Alansplodge (talk) 16:41, 23 February 2017 (UTC)
- See also invasive species for an understanding of why, even if you could, doesn't mean you should.--Jayron32 18:53, 24 February 2017 (UTC)