Wikipedia:Reference desk/Archives/Science/2016 February 1
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February 1
[edit]Breached levee near town
[edit]Let's suppose, for argument's sake, that a 400-kV power line becomes submerged by a flood and somehow remains live (not very realistic, I know) -- how far away can it kill a person who is also submerged in the flood and is clinging to a metal object? (Question inspired by 911 First Responders mission #8, "Breached levee near town".) 2601:646:8E01:9089:F88D:DE34:7772:8E5B (talk) 02:10, 1 February 2016 (UTC)
- High voltage electricity is very dangerous! A very tiny exposure can be instantly fatal - especially if the source is a high voltage transmission line. The general advice, even for emergency-crews, is to "avoid the area completely." But since you're asking for a little bit more of a quantitative answer, I looked around for some good sources.
- From electrocution, you can find several references on the topic of electric shock. Sources vary in defining a level of current that is lethal or causes irreversible harm; but somewhere in the neighborhood of half an ampere at 100 volts is pretty much a guaranteed killer for a human. In some cases, a much lower current will be fatal. If the voltage is much higher or much lower, the lethal current level becomes very difficult to predict, and as a general rule, scientists haven't been able to collect great data on that.
- So, how far away can you be from a live wire, and still get half an ampere? Well, it depends on the electrical path. You could be miles away from the wire, if you're touching a metal object that makes you the shortest path between high voltage to ground. If there is water or flooding, the electrical paths can become very difficult to predict. So, the answer is going to vary wildly.
- The U.S. Department of Transportation publishes an annual HAZMAT Emergency Response Guidebook. (We even have an article: Emergency Response Guidebook!) That book is my go-to resource when I need to know how many hundreds of feet away from a hazard I need to stay - they publish standard safety-perimeter guidelines for all kinds of things, from fires to noxious gases to radiological hazards, and more!. Regrettably, they do not publish any guidance for a safe distance from exposed high-voltage wires. (If I may reiterate: any distance is hazardous if there is an electrical path from the high-voltage to you).
- Here's a study guide from Los Alamos: Electric Hazard Safety Awareness. I read through it, and the short answer is, do not approach. Even trained professionals are instructed not to approach an unknown electrical hazard. Additional guidelines are prescribed for various levels of qualified/trained personnel, with- and without- personal protective equipment. For example, even a trained expert wearing PPE (protective gear) is instructed never to approach within 4 feet of a high voltage (230kV) conductor, even if it has no damage. In our OP's question, there is clear evidence of damage (due to flooding, and so on). The correct procedure - even for the emergency responders - is to "get the heck out of there!" The situation is very unsafe until we can be positively certain that the line is de-energized. After the line is shut off, and everybody is sure it is off, then the emergency crews can get in and start helping.
- Here is a guideline aimed at the general public, from my local electric company: What to Do If You See a Downed Power Line. Again, the correct answer is get the heck out of there.
- Nimur (talk) 03:22, 1 February 2016 (UTC)
- Not sure if it would be miles. Perhaps if the water was all perfectly insulated from the ground and you were touching the only path to ground, but that doesn't describe the case of a breached levee. There are bound to be many paths to ground, over the course of miles, in all directions. So then the question is if your path to ground is still significant, compared with all those others, factoring in the resistance of the water over all that distance. I suggest that looking for empirical data might be the best approach here, of actual electrocutions at extreme distances from the source, during floods, rather than attempting a theoretical answer. (The "if can see it stay away" advice sounds good, though, as you couldn't see it from miles away.) I also imagine rescue personnel must have a guide they use, as the question of whether to attempt a rescue (that requires getting into the water some distance from live wires) has to come up. StuRat (talk) 03:35, 1 February 2016 (UTC)
- This is going to have to do with the resistance of the actual soil and underlying rock in some way. Exactly what way, I can't guess... on one hand, if the ground is very conductive it should allow more current to dissipate deep downward, so the potential should fall off faster ... on the other, if the potential falls off faster, then your chance of actually getting a fatal shock crossing your body within that region should be higher. I imagine if the ground composition varies you might have a worst-of-both-worlds scenario - for example, you could have a pool of water lying on a big rubber sheet with a power line sparking, and the edge of that could be at almost the voltage of the live wire, but at the edge there is ground conductance and so there's a huge difference between your belly and your butt. Wonder if there's as much salt in the water as in your body...? don't know, but this seems like it needs a very specific solution for the exact scenario. Wnt (talk) 17:55, 1 February 2016 (UTC)
- A more likely scenario would be a river that has burst its banks, and a downed power line somewhere in the floodwater (sort of like in the video I linked). So a fair approximation would be an inverted bell curve-shaped channel filled with river water, with the power line at the center of its upper (flat) surface. And the victims are either floating (floundering) in the water, or clinging to various objects (streetlamps, chain-link fences, trucks, etc. -- note that the 3 types of objects I listed are highly conductive), and are partly immersed in either case (let's assume up to their waist).2601:646:8E01:9089:F88D:DE34:7772:8E5B (talk) 09:59, 2 February 2016 (UTC)
- I'd just like to address the bit about the "power line... somehow remains live (not very realistic, I know)". The overload protection on power lines is often not as quick-acting as household circuit breakers. For example, in this report on the Second Great Northeast Blackout, if you search for the word "seconds" you will find several instances where a trunk line did not trip out until several seconds after it was overloaded. In addition, power-line protection may be configured to automatically try reapplying power once or twice a few minutes after it has tripped out. So for both reasons, people in the danger zone, however large it is, will be at risk. --76.69.45.64 (talk) 04:56, 1 February 2016 (UTC)
- In this mission, the power line actually remains live until you order your engineer to manually shut it off -- which is the part that's obviously bullshit. Take a look at this: https://www.youtube.com/watch?v=mUEKtRv3uxA&list=PLsQxuO6DkZTGC-_D2u7A_Nn3V3AyYSNRD&index=8 (from 0:49 to 1:36). 2601:646:8E01:9089:F88D:DE34:7772:8E5B (talk) 07:19, 1 February 2016 (UTC)
- Actually that sounds quite reasonable from the responder's point of view. They don't know for sure how often the current might be reapplied... until they have an expert from the company tell them the line is securely disabled, they would be smart to consider it as live. Wnt (talk) 17:55, 1 February 2016 (UTC)
- You're right that regardless of how unlikely it is that the line is still live, it's probably going to be considered live by emergency responders until the power supply engineers certify that it is safe. And they will have their own procedures to go through which I suspect again aren't going to just assume it isn't live because it's very unlikely. Assumptions wouldn't have applied in this case anyway [1] but it does demonstrate how these things work. Nil Einne (talk) 13:25, 2 February 2016 (UTC)
- Honestly, I'm not entirely sure of the definition of a "live" wire, and it's kind of troublesome to look up. From first principles I wouldn't necessarily go by the voltmeter: suppose, for example, I were trying to change out the old outlets in a house with a friend before repainting, and the power goes out. To me, the black wire I'm not touching is still the "live" wire, because I'm still not going to be touching it. With the power to the building visibly out, I can picture he might ask me whether the wires in an outlet in the other room are live, and I'd take that to mean, did I make sure the breaker was off before the power went out? But I don't know if that's how professionals use the term. Wnt (talk) 16:16, 2 February 2016 (UTC)
- The reference I linked earlier - the Electrical Hazard Awareness study guide from Los Alamos National Laboratory - provides some guidance for when a part or a wire is treated as "live." They also have a diagram (Figure 37) that provides some reference distances for a live wire in contact with the ground. Note that the booklet does not actually declare a safe distance - but they do explain that you get progressively less unsafe at greater distances.
- The general guidance provided by that pamphlet, which is paraphrased from multiple Federal government regulations (cited in the guide-book), is that a live part is one that might be energized. It is treated as "live" until it is locked out and tagged out and tested. This is the basic rule for equipment when there is no damage. If there is damage, the entire area is treated as "live" or hazardous.
- Why did I look to Los Alamos for reference material on this topic? Because they - and their private-sector partner Sandia National Laboratories - are the world experts in safe handling of very high voltage systems. Those guidelines are generally applicable in any environment where you might encounter very high voltages, such as a physics laboratory, a radio transmission facility, or a power transmission facility.
- While we are on the topic of terminology, the guidebook also brings up a very important point regarding the phrases "high voltage" and "low voltage. When we say "low voltage" in these contexts, we do not automatically mean "safe voltage." A 240 volt system may sometimes be categorized as "low voltage." Such a "low voltage" system - and even a much lower voltage system, in the right conditions - can still cause fatal shock.
- Nimur (talk) 21:35, 2 February 2016 (UTC)
- Honestly, I'm not entirely sure of the definition of a "live" wire, and it's kind of troublesome to look up. From first principles I wouldn't necessarily go by the voltmeter: suppose, for example, I were trying to change out the old outlets in a house with a friend before repainting, and the power goes out. To me, the black wire I'm not touching is still the "live" wire, because I'm still not going to be touching it. With the power to the building visibly out, I can picture he might ask me whether the wires in an outlet in the other room are live, and I'd take that to mean, did I make sure the breaker was off before the power went out? But I don't know if that's how professionals use the term. Wnt (talk) 16:16, 2 February 2016 (UTC)
- You're right that regardless of how unlikely it is that the line is still live, it's probably going to be considered live by emergency responders until the power supply engineers certify that it is safe. And they will have their own procedures to go through which I suspect again aren't going to just assume it isn't live because it's very unlikely. Assumptions wouldn't have applied in this case anyway [1] but it does demonstrate how these things work. Nil Einne (talk) 13:25, 2 February 2016 (UTC)
- Actually that sounds quite reasonable from the responder's point of view. They don't know for sure how often the current might be reapplied... until they have an expert from the company tell them the line is securely disabled, they would be smart to consider it as live. Wnt (talk) 17:55, 1 February 2016 (UTC)
- In this mission, the power line actually remains live until you order your engineer to manually shut it off -- which is the part that's obviously bullshit. Take a look at this: https://www.youtube.com/watch?v=mUEKtRv3uxA&list=PLsQxuO6DkZTGC-_D2u7A_Nn3V3AyYSNRD&index=8 (from 0:49 to 1:36). 2601:646:8E01:9089:F88D:DE34:7772:8E5B (talk) 07:19, 1 February 2016 (UTC)
"Sleeping funny" and sore neck
[edit]In scientific, descriptive terms, what exactly do you do when you "sleep funny"? What is it that your sleep posture does to your muscles that causes sore neck the next day? --98.115.39.92 (talk) 04:12, 1 February 2016 (UTC)
- Well, for one thing, if your neck is misaligned during sleep, then some of your neck muscles would be stretched, which is what causes the pain and soreness. FWIW 2601:646:8E01:9089:F88D:DE34:7772:8E5B (talk) 07:11, 1 February 2016 (UTC)
- I suspect that the reverse is also true, and those muscles or ligaments that are shortened while you sleep take some time to stretch back to normal length, and during that time your neck is sore (which is to prevent you from trying to stretch them too quickly and tearing them). StuRat (talk) 08:04, 1 February 2016 (UTC)
- Assuming that the connection between stretched muscles and soreness afterward is correct, how exactly does former cause the latter? What does being in a stretched state for an extended amount of time do to muscle tissues? How does the condition manifest as soreness? --98.115.39.92 (talk) 12:10, 1 February 2016 (UTC)
- See cramp or Strain (injury) for some discussion of the possible causes. --Jayron32 15:58, 1 February 2016 (UTC)
- Do we have an article on tossing and turning? I find that helps alleviate the problem. It's only when I am highly medicated that I usually wake up in the same position in which I went to sleep. μηδείς (talk) 19:42, 1 February 2016 (UTC)
What is encoded?
[edit]Which of the following sentences is logically correct?
- Gene XYZ is encoded on Chromosome 5.
- The Protein XYZ is encoded in Gene XYZ on Chromosome 5.
The questions are - and both views/expressions are found in WP - "Are genes encoded?" or "Are Proteins encoded?". Thanks for comments. Play It Again, SPAM (talk) 08:41, 1 February 2016 (UTC)
- Google finds roughly equal numbers of hits for "(XYZ) gene is encoded" ("The gene is encoded on murine chromosome 5") and "(XYZ) protein is encoded" ("The XK protein is encoded by a gene on the X chromosome"). I suppose either is valid - maybe "The gene is encoded" makes slightly more sense, since a gene is an abstract thing while a protein is a physical thing (like how "The selfie is encoded in this file" makes a bit more sense than "My face is encoded in this file"). A protein can also be "coded for" ("It is not known whether the terminal protein is coded for by a viral gene"), while I don't think genes are ever "coded for". Smurrayinchester 14:38, 1 February 2016 (UTC)
- Unfortunately there's lots of loose terminology floating around, even from good sources. Smurray's description is reasonable, but note that a gene is locus or place in a strand of DNA. Whether a place is an abstract concept or a physical thing depends a bit upon the ontology and context you're operating in. But mostly, you'll do well to think of a gene like an address, and treat it grammatically the same as you'd treat at address.
- I think this confusion in usage over encoding is related to the frequent conflation between genes and alleles. Pretend there's exactly one gene that determines human eye color, and that humans have eyes that are only brown, blue, or green. Then it is correct to say "there is a gene for eye color", but it is strictly incorrect to say "I have the gene for brown eyes". We should instead say "I have the allele for brown eyes". Even Nature gets sloppy [2], talking about genes. Anyway, linguistic descriptivism is fine for informal usage of natural language, and we can seek to not say how things ought to be and instead focus how they are.
- But science ultimately seeks to codify and formalize its language - we don't like imprecision and vagueness, we want clear and concise nomenclature, sometimes lives depend on it! Thus, a gene is not encoded on chromosome 5, it is simply located on chromosome 5, just as my address is located on my street. SemanticMantis (talk) 15:42, 1 February 2016 (UTC)
- In my opinion Gene XYZ is encoded... is incorrect and ought to be avoided. A gene can be located on a chromosome, but it is itself a piece of code, and to say that a piece of code is encoded would mean that the final product is encoded twice -- in other words I basically agree with SemanticMantis. Looie496 (talk) 15:52, 1 February 2016 (UTC)
- Indeed. It's is the protein that is encoded by the DNA sequence on the gene. Fgf10 (talk) 17:15, 1 February 2016 (UTC)
- I agree; "encoded" typically refers to the genetic code. An amino acid is represented by a genetic code in DNA; a gene simply is DNA and so is on a chromosome. However.... as always, there's a catch. Biology hates semantics... so do biologists... even so both use them with reckless abandon. An organism is full of "codes", as some author or other will use the metaphor; for example [3] the "cytosine methylation code". And so in that sense a gene is encoded in DNA and DNA modifications and histones and histone modifications and other DNA-bound proteins and so on. My feeling is that this is not the standard way of speaking but that is purely arbitrary; there's no majority vote over what metaphors to use and there is no way to know whose preferred metaphors will win out in fifty years. There is a certain historical appeal to the notion that a gene is encoded, however, since the definition of genes long predates the knowledge that DNA exists. Wnt (talk) 17:47, 1 February 2016 (UTC)
- I am a biologist, and I love discussing semantics. People say "that's just semantics" to dismiss things all the time, but that doesn't make it a sound complaint. What they often mean is "let me be sloppy with my words and use them in inconsistent ways", and that can get us in to a lot of trouble with misunderstandings. Really, we need to agree on what the hell we mean when we use certain words if we have any hope of discovering, teaching, or learning things in science :) SemanticMantis (talk) 19:54, 1 February 2016 (UTC)
- I'm 100 % behind you. To be as precise as possible when describing scientific facts.
- Thanks for the contributions. They confirm my point of view. However, I will not change the "gene is coded on chromosome" in the various articles, but will look to avoid such a formulation. THX! Play It Again, SPAM (talk) 07:06, 3 February 2016 (UTC)
- Hi there, we've had the same discussion on de.wp. I agree with Play It Again, SPAM, that the correct semantic for 'coding' would only be the translation of a string into another string, and not also the string itself (as in the case 'gene encoded on chromosome'). Nevertheless, the "sloppy" use of the word is widely distributed in scientific text books, and according to NOR, we accept that a terminology might be sloppy. In this case, if the scientific literature uses coded in the context of genes, it's acceptable. Cheers, --Ghilt (talk) 08:56, 3 February 2016 (UTC)
- I am a biologist, and I love discussing semantics. People say "that's just semantics" to dismiss things all the time, but that doesn't make it a sound complaint. What they often mean is "let me be sloppy with my words and use them in inconsistent ways", and that can get us in to a lot of trouble with misunderstandings. Really, we need to agree on what the hell we mean when we use certain words if we have any hope of discovering, teaching, or learning things in science :) SemanticMantis (talk) 19:54, 1 February 2016 (UTC)
- I agree; "encoded" typically refers to the genetic code. An amino acid is represented by a genetic code in DNA; a gene simply is DNA and so is on a chromosome. However.... as always, there's a catch. Biology hates semantics... so do biologists... even so both use them with reckless abandon. An organism is full of "codes", as some author or other will use the metaphor; for example [3] the "cytosine methylation code". And so in that sense a gene is encoded in DNA and DNA modifications and histones and histone modifications and other DNA-bound proteins and so on. My feeling is that this is not the standard way of speaking but that is purely arbitrary; there's no majority vote over what metaphors to use and there is no way to know whose preferred metaphors will win out in fifty years. There is a certain historical appeal to the notion that a gene is encoded, however, since the definition of genes long predates the knowledge that DNA exists. Wnt (talk) 17:47, 1 February 2016 (UTC)
- Indeed. It's is the protein that is encoded by the DNA sequence on the gene. Fgf10 (talk) 17:15, 1 February 2016 (UTC)
GLUT-4
[edit]What is GLUT-4? What is its role in biological system?
- GLUT4, is a protein encoded, in humans, by the GLUT4 gene. GLUT4 is the insulin-regulated glucose transporter found primarily in adipose tissues and striated muscle (skeletal and cardiac). Wikipedia has an article about GLUT4. AllBestFaith (talk) 15:44, 1 February 2016 (UTC)
- Interestingly enough, that first sentence is also a good example of how to write correctly about this stuff, related to User:Play It Again, SPAM's question directly above. SemanticMantis (talk) 15:46, 1 February 2016 (UTC)
- Should be: GLUT4 is a protein encoded, in humans, by the gene GLUT4 (italics if it is human). Play It Again, SPAM (talk) 16:23, 1 February 2016 (UTC)
- It is an awful example. It tells you exactly nothing, and is far too human focussed. The second sentence would be the correct opening one. Fgf10 (talk) 17:14, 1 February 2016 (UTC)
- What source requires "italics if it is human"? The HUGO Gene Nomenclature Committee recommends "Proteins should be designated using the same symbol as the gene, printed in non-italicized letters." AllBestFaith (talk) 19:09, 1 February 2016 (UTC)
- The one you cite: "It is recommended that gene and allele symbols are underlined in manuscript and italicized in print; protein symbols should be represented in standard fonts." Play It Again, SPAM (talk) 07:00, 3 February 2016 (UTC)
- I don't see how one mention can make one sentence "too human focussed". The article may be too human focused, but I only wanted to point out that "XXX is a protein encoded by the YYY gene" is a good simple way to phrase these kinds of statements, and an example of WP doing it more or less correctly, as compared to the incorrect usage mentioned above. The sentence doesn't tell us nothing; it tells us precisely that that GUT4 is a protein, and it also tells us the name of the gene that encodes the protein in humans. And if you want to get critical, then the second sentence is a terrible opener, because it doesn't tell us what basic type of thing GUT4 even is. But issues of WP writing style are far off topic for this forum and post, as are issues of what things should be put in italics, so let's just leave this unless the OP needs further clarification on GUT4. SemanticMantis (talk) 19:48, 1 February 2016 (UTC)
- Human protein X is encoded by human gene X? Well duh. What if people aren't even interested in human GLUT4 for starters? What is the number one thing anyone looking at the article want to know? What GLUT 4 does. But yes sure, let's not mention that in the opening sentence, you're perfectly right. Fgf10 (talk) 21:24, 1 February 2016 (UTC)
- What source requires "italics if it is human"? The HUGO Gene Nomenclature Committee recommends "Proteins should be designated using the same symbol as the gene, printed in non-italicized letters." AllBestFaith (talk) 19:09, 1 February 2016 (UTC)
- Interestingly enough, that first sentence is also a good example of how to write correctly about this stuff, related to User:Play It Again, SPAM's question directly above. SemanticMantis (talk) 15:46, 1 February 2016 (UTC)
- It's incidentally an example of a syntactic quirk that I find myself changing surprisingly often: why O why a comma between the subject and 'is'? —Tamfang (talk) 21:51, 3 February 2016 (UTC)
- For comparison, see [4]. Their article looks like it might have had a dubious move recently, and it is not really very approachable either, and it's also very... agglutinative, made up of paragraphs written in all likelihood at different times if not by different people. Mostly though, it's long, and all the style quibbling aside, the longer the better. Wnt (talk) 18:52, 2 February 2016 (UTC)
Whiskey warehouses
[edit]A wine cellar is a special type of cellar needed for the best production of wine. What about whiskey warehouses? Are they just warehouses in which the distiller stores whiskey, or are they an important part of the whiskey production process? The question arises from File:Rock Spring Warehouse from southeast.jpg, which depicts a whiskey warehouse. Nyttend (talk) 15:45, 1 February 2016 (UTC)
- They are important insofar as aging of Whisky is important, i.e. very! Here are a few pages that discuss how temperature, humidity, and fluctuations of those affect whisky aging rate and process [5] [6] [7]. While an old shack might not look that impressive, my last link above specifically mentions how in many cases natural changes in humidity/temp like those found in an attic or barn are desirable, because this sort of "pumps" tasty wood molecules into the otherwise boring ethanol and water mixture. (This also applies for the real balsamic vinegar). I might be able to find more serious/academic refs if you need something more reliable than the links above. SemanticMantis (talk) 15:54, 1 February 2016 (UTC)
Why is air conditioning considered a luxury but heating is considered a necessity?
[edit]Don't people die from heat stroke just as often as hypothermia? Is this more of a political issue where land lords can merely use the excuse that air conditioning is a luxury to save money on not providing it? ScienceApe (talk) 19:31, 1 February 2016 (UTC)
- What is the basis for your premise? ←Baseball Bugs What's up, Doc? carrots→ 22:20, 1 February 2016 (UTC)
fporq
- Heating has been around since before we were Homo sapiens. Air conditioning is relatively recent, and people who lived in hotter climes were usually better adapted to them, such as being longer-limbed and less broad-chested. Look at Allen's Rule and Bergmann's Rule. The insistance that air-conditioning is a luxury is usually a political one, see these articles. μηδείς (talk) 19:38, 1 February 2016 (UTC)
- According to the CDC [8], it seems that there are more cold-related deaths than heat related deaths in the US (though the article is a bit of a dense read). Another way to look at it is mitigation methods. If it is too hot, there are a lot of recommended actions other than just "air conditioning," such as proper and frequent hydration, stick to shade and reduced activity, moving air/a fan, dressing down, etc. If it is cold, you can dress warmly, but that is about it short of some method of heating, be it burning stuff (dangerous or not an option in many residences) or having heat. --OuroborosCobra (talk) 19:42, 1 February 2016 (UTC)
- I disagree. In cold climates, it's a trivial cost to buy a small electric heater and warm up whatever spot in the house you're at and passive insulation (clothing, blankets) allow you to trap body heat. You don't need "central" heating (although it may be desirable). When it's only mildly hot - you're right, there are possible mitigations. But when the air temperature exceeds body temperature - you are in trouble. Fans actually make matters worse and none of the tricks you describe are going to get you even modestly comfortable. That's something you can withstand for a day or two - but when the temperature stays above body heat for weeks - you need A/C. Small air conditioners are not very effective (and they're a lot more costly than small heaters) - so central airconditioning is something close to a necessity in seriously hot climates.
- We should also consider vehicles. In a gasoline powered car, heat comes for free as a by-product of running the engine - but running the A/C requires extra energy and lots of expensive equipment. In that situation, heat is clearly not a luxury in any climate - but A/C is unnecessary in large parts of the world. (My wife's car has air-conditioned seats...that's a luxury...but really nice on a hot day!) SteveBaker (talk) 19:53, 1 February 2016 (UTC)
- Air temps can exceed body temps without presenting any danger, so long as humidity is low. There are many inhabited parts of the world where this occurs each summer. In my location (Detroit), I can't see why anyone with water service should die from heat, since water delivered by underground pipes is cool enough, even on the hottest days, to cool you off. On the other hand, if gas and electricity was cut off in winter, I could see people dying from the cold. StuRat (talk) 04:09, 2 February 2016 (UTC)
- True. I've walked at 104°F in the sun at low humidity (by forest biome standards) and it'd need to be somewhat hotter than that for that humidity level to be too much. If humans didn't sweat that would quickly lead to death (which is why pigs lie in mud and dogs pant). One of the most dangerous dew points ever recorded on Earth was near Green Bay, Wisconsin because the crops prevent the humidity from going down with the temperature rising (until the crops' water is exhausted). Sagittarian Milky Way (talk) 04:31, 2 February 2016 (UTC)
- Yeah, the mitigation issue really seems to work the opposite way from OuroborosCobra's point. There's a saying in Canada: There's no such thing as bad weather, only bad clothes. The right clothes can keep you safe down to well below zero Fahrenheit.
- But that only works for cold weather. In hot weather, your ability to adjust by way of clothing is pretty limited. --Trovatore (talk) 23:13, 1 February 2016 (UTC)
- But who said we're only talking about central heating? If you're using any form of active heating then you're surely using heating, whether it's a fireplace, a small electrical heater, an electric blanket or whatever. In NZ, central heating is still fairly rare, but most homes do have some form of heating. Nil Einne (talk) 12:31, 2 February 2016 (UTC)
![](http://upload.wikimedia.org/wikipedia/commons/thumb/7/71/CPonte_anthill2.jpg/220px-CPonte_anthill2.jpg)
- I think it depends on where you are in the world. When I lived in south-eastern England, you really wouldn't use air conditioning (A/C) for more than maybe a couple of days in the year. Having such costly systems just sitting there in house and car for the very rare occasion when it would have been useful was indeed a "luxury" that just about everybody managed perfectly well without. On the other hand, I now live in Texas - and just last Saturday (late January!) felt the need to turn on the A/C for a brief period of time to cool off the house. In the summer months, when temperatures always top 35 degC and usually reach 40 degC for one to two weeks, it's decidedly not a luxury! If I had to choose one or the other, I'd definitely choose A/C over central heating here in Texas because on the very few days you really need that heat, you can provide it with an old-fashioned fireplace and a handful of small spot-heaters.
- Hence, your perception of whether A/C is a luxury or not depends entirely on where you live. Clearly there are some climates between that of south-east England and the heart of Texas where one might find considerable debate whether A/C is a luxury or not. SteveBaker (talk) 19:44, 1 February 2016 (UTC)
- With the A/C in the UK You will dry the air with high humidity, in TX You are cooling it. --Hans Haase (有问题吗) 22:05, 1 February 2016 (UTC)
- Many commodities that were perhaps considered "luxuries" at one time are now standard. Indoor plumbing, for example. Electricity. Telephones. Cars. On and on it goes. ←Baseball Bugs What's up, Doc? carrots→ 22:22, 1 February 2016 (UTC)
- I grew up in swamp country just 30 miles west of New Orleans, long enough ago that we didn't get air conditioning until I was about 11 years old. Before then, We made do with a large (three foot wide) ducted fan which drew hot air out of the house into our attic, where roof-mounted turbines vented the hot air outdoors. And we drank many glasses of water over ice, and we played outside a lot. We were aware of the danger of heat stroke, but we were also more commonsensical back then.
- We knew to stay hydrated and, if we needed to be indoors in the heat, to lie as close to the floor as possible, where the cool air was (on sweltering nights, this worked very well). Workmen who had to be outdoors in the hot midday never went far from the large water cooler every work truck had as standard equipment. In fact, every home had one or two insulated coolers just for summer outings, because we knew we had to keep hydrated and as cool as possible. And I remember during heat waves that the television news always reminded us of these and other ways to survive extreme heat. Air-conditioning was a "nice to have" item, not a necessity, unless one had a medical issue.
- In contrast, I've also lived in Indiana, about thirty miles north of Indianapolis, in a wood-heated farmhouse. It was "burn wood or die," because electric heaters are inadequate to winter nights where the temperature's in negative numbers in Fahrenheit OR Celsius. So are even multiple layers of warm clothing - without a good fire in your wood stove, you'll just be a heavier corpse for the rescue squad to pull out to the meat wagon. Heating isn't a luxury north of the Mason-Dixon Line, it's a vital necessity. loupgarous (talk) 23:58, 1 February 2016 (UTC)
- We had this argument at work when some managers would set the temperature at 75, and others at 68. The question was, do yo want people who are too cold at 72 to put on more clothes, or do you want those who are too hot at 72 to strip naked. μηδείς (talk) 00:30, 2 February 2016 (UTC)
- ¿Por qué no los dos? --Trovatore (talk) 08:27, 2 February 2016 (UTC)
- We had this argument at work when some managers would set the temperature at 75, and others at 68. The question was, do yo want people who are too cold at 72 to put on more clothes, or do you want those who are too hot at 72 to strip naked. μηδείς (talk) 00:30, 2 February 2016 (UTC)
- So basically, to summarise Vfrickey's argument, it's entirely possible (more difficult, but definitely not impossible) to function during hot summers without air conditioning, much easier than it is during winter with no heat. Consider that people in temperate and polar regions have always heated their homes (whether with open fires or with more sophisticated systems), but the tropics have been inhabited since time immemorial by people who didn't have air conditioning, which itself wasn't invented until the twentieth century. And Bugs, remember that "standard" and "necessity" are quite different; heating is absolutely necessary for human life (whether sun-provided, geothermal, or artificial heat), unlike phones and indoor plumbing, and Jim.henderson could tell you whether cars are a necessity. Nyttend (talk) 01:45, 2 February 2016 (UTC)
- Technically, the only "necessities" are what keep us alive: food and shelter. Everything else is a "luxury". ←Baseball Bugs What's up, Doc? carrots→ 05:45, 2 February 2016 (UTC)
- Possibly - but if "something that keeps you alive" is not a luxury - then how do you align your statement against the fact that the estimated 70,000 deaths that were caused by the 2003 European heat wave that would largely have been saved if those people had used air conditioning? SteveBaker (talk) 14:30, 2 February 2016 (UTC)
- Good question. I'll let Nyttend answer it. :) But consider this: Without A/C you might die. Without food you will die. ←Baseball Bugs What's up, Doc? carrots→ 14:48, 2 February 2016 (UTC)
- Well quite a few deaths due to the cold would be prevented if people were living somewhere with a reverse cycle air conditioners. Likewise most deaths due to starvation would be prevented if people had access to caviar, kobe beef, truffles, Noirmoutier-en-l'Île potatoes perhaps with some Roman Ruby grapes and Yubari King melons thrown in. (A few refinements and appropriate advice and you'd also avoid many deaths due to malnutrition.) That doesn't mean any of these aren't likely to be consider a luxury. (And ironically the former is potentially more power efficient than eletrical resistive heating depending on how much you try to heat with on vs the other.) In other words even if it's true that many of the deaths would have been avoided with airconditioning, the more relevant question is whether they could have been avoided without airconditioning (or migrating). Nil Einne (talk) 13:05, 3 February 2016 (UTC)
- Food is food. And if they had had the resources to pick up and move, they probably also would have had the resources to invest in A/C. ←Baseball Bugs What's up, Doc? carrots→ 14:53, 3 February 2016 (UTC)
- Possibly - but if "something that keeps you alive" is not a luxury - then how do you align your statement against the fact that the estimated 70,000 deaths that were caused by the 2003 European heat wave that would largely have been saved if those people had used air conditioning? SteveBaker (talk) 14:30, 2 February 2016 (UTC)
- Technically, the only "necessities" are what keep us alive: food and shelter. Everything else is a "luxury". ←Baseball Bugs What's up, Doc? carrots→ 05:45, 2 February 2016 (UTC)
- So basically, to summarise Vfrickey's argument, it's entirely possible (more difficult, but definitely not impossible) to function during hot summers without air conditioning, much easier than it is during winter with no heat. Consider that people in temperate and polar regions have always heated their homes (whether with open fires or with more sophisticated systems), but the tropics have been inhabited since time immemorial by people who didn't have air conditioning, which itself wasn't invented until the twentieth century. And Bugs, remember that "standard" and "necessity" are quite different; heating is absolutely necessary for human life (whether sun-provided, geothermal, or artificial heat), unlike phones and indoor plumbing, and Jim.henderson could tell you whether cars are a necessity. Nyttend (talk) 01:45, 2 February 2016 (UTC)
- I think Vfrickey is wrong, though. It's mostly a matter of insulation. I simply don't believe the claim that you can't put on enough insulation to survive inside in an Indiana winter, without heating. I call bullshit. --Trovatore (talk) 01:55, 2 February 2016 (UTC)
- See Igloos. Those are in far worse conditions than Indiana. Ian.thomson (talk) 02:09, 2 February 2016 (UTC)
- For the record the hardiness zone map shows an average year reaching a hair under -10°F in that location and Indianapolis says the record low is -27°F. Maybe the cabin had no modern insulation or even was leaky and/or they didn't have much clothing. The point still stands that it's probably easier for healthy housemates without heat, thick clothes and cooling but with running water to die in coldish inhabited places than in the hottest. Sagittarian Milky Way (talk) 02:41, 2 February 2016 (UTC)
- I'll put the lake effect snowfall in metro Indianapolis, when it got that far south, up against the worst that Buffalo gets. We're talking six feet of snow in a day. That's the sort of thing that doesn't show up on maps. Not too bad if you have a nicely heated home (having to dig your car out of a snowbank with a shovel is worth a few chuckles), but a definite challenge in a home without heat, which was my original point. Those healthy housemates would fare a lot better in the Gulf South on our hottest days without air conditioning than in central Indiana without heat, which was the original poster's question. Heat's more necessary in cold weather than air conditioning is in warm weather, all other things being equal. loupgarous (talk) 05:24, 2 February 2016 (UTC)
- I think Vfrickey is wrong, though. It's mostly a matter of insulation. I simply don't believe the claim that you can't put on enough insulation to survive inside in an Indiana winter, without heating. I call bullshit. --Trovatore (talk) 01:55, 2 February 2016 (UTC)
- (edit conflict)I have to second SteveBaker's point that it depends on where you live. In my home town during the summer, the local news regularly goes on and on telling people to keep children and the elderly hydrated, and inside and air conditioned. Winter? Nothing unless it snows, and then it's only "these schools are closed, this gas station was caught mixing gas into their kerosene, and wow, everyone bought out all the milk, eggs, and bread like it's the end of the world or something." Yes, people managed to live there before air conditioning, but it was still by far more dangerous than winter (though most of the people dying were poor and/or black, which is probably why my older relatives don't think about summer being so dangerous). Ian.thomson (talk) 02:09, 2 February 2016 (UTC)
More so is the age of the home or building. People have lived in the desert and the arctic for much longer than either central air or heating. Structures were built with the current technology in mind so current structures support whatever climate control is available. A house built in the desert before air conditioning is quite different than today. --DHeyward (talk) 02:35, 2 February 2016 (UTC)
- I'd like to revisit my remarks. I was one of the dads who actually went along with their kids on Scout campouts in that Indiana town, and was frankly incredulous (we'd just moved there from the Gulf Coast) that the troop would go camping in minus-10F weather. And we had thick clothing (I'd gotten my bachelor's degree in North Louisiana, where quilted overalls are standard hunting equipment, and still had them), but a lack of knowledge and confidence in how to deal with the cold. It turns out that two closed-cell foam pads under a winter-grade sleeping bag will actually keep you alive in a tent at those temperatures. And our farmhouse was indifferently insulated; the prior occupants apparently had plenty of wood, every winter, and that was a remarkably efficient wood stove at heating the rooms of that place we lived in.
- And even so, I call bullshit on Trovatore's "bullshit". I was THERE. A drafty farmhouse with so-so insulation is a different matter than a tent that probably has a warmer air space by conserving the 500W or so body heat from each occupant in a small area.
- Hypothermia is quicker to kill and harder to remedy than heat prostration. We got along better in the southern heat without air conditioning (though we got spoiled to the A/C in no time at all) for years, and the ambulances weren't zooming through the streets picking up the dead and dying from heat stroke. People probably deal better with what they're used to, our native Hoosier neighbors weren't fazed at all by the cold (though there were regular reports of hypothermia deaths in the local news).
- People also tend to panic and do stupid shit in unfamiliar weather. A homeless man in New Orleans set a fire in the alcove of an office building on Canal Street (think "Broadway in New York") during last week's cold snap and wound up setting a six-alarm fire. I'm willing to believe that he wasn't the sharpest pencil in the box to begin with, but that the cold impaired his judgment and perhaps caused him not to do the sensible thing and visit the local Salvation Army shelter for the night. Fortunately, he survived the blaze, and no one else was hurt. loupgarous (talk) 04:57, 2 February 2016 (UTC)
- Maybe the shelters were full and this action got him a warm place to spend the night, if only in jail. StuRat (talk) 06:47, 2 February 2016 (UTC)
- "We got along better in the southern heat without air conditioning...for years, and the ambulances weren't zooming through the streets picking up the dead and dying from heat stroke." - Lack of air conditioning doesn't equate to lack of cooling. Here in Texas, I know a lot of people who grew up without that big freon-based refrigeration plant in their homes - instead, they used things called "Swamp coolers" which use the evaporation of water in a forced airflow to actively cool the air. One guy told me that although his family were dirt poor farmers, they used a big fan to push air through a stack of hay bales that they soaked with water from a hose every morning. Our article points out that variations on this idea were around as early as 2500 BC. So the idea that people back in the days before air conditioning lived without active cooling systems isn't exactly true.
- Furthermore, in areas unprepared for extremes of heat, even fairly routine Texas summer conditions can cause huge numbers of deaths. Consider the 2003 European heat wave - where temperatures reached 40 degC for just one week - and thousands of people died. 40 degC happens routinely every single summer in Texas - and a couple of years ago, we had 70 consecutive days with those kinds of temperatures - and the death toll was minimal. People in Europe were given the standard advice for coping with the heat - the lack of A/C or other active cooling systems seems to have been a large part of the problem.
- The difficulty in 2003 seems not to be so much with the daytime temperatures - but with the fact that the temperatures didn't drop significantly at night. This is also a property of Texas summers.
- Another point in favor of A/C units is that they work well in high heat and high humidity - they remove humidity from the air, so even without cooling, they make sweating more effective. Swamp-coolers (and other variations on evaporative cooling) do very poorly in high humidity. High humidity combined with high temperatures are often what kills people because sweating becomes ineffective and using passive fans and wearing light clothing don't help when the ambient temperatures are above body heat.
- So considering how people survive in desert conditions (very low humidity) and when there are cooler nights, and when evaporative coolers were the norm doesn't explain why A/C is not a luxury in high-humidity/high-temperature areas where it does not cool off much at night.
- SteveBaker (talk) 14:09, 2 February 2016 (UTC)
- Though some of the stories above are interesting, I'm afraid this is becoming one of those threads our detractors will showcase as an example of how lousy we are as a refdesk. It's not hard to search out sourced commentary about this (though perhaps not so good as ours, really): [9] There are legal discussions like [10]. I don't really know how to find the good ones though; this is more a Humanities question of philosophy than one of science, or at least, we need a philosophical basis before we can evaluate a scientific issue.
- Now that that's out of the way, I'll say that personally a major issue is the noise of AC systems. To turn on heat is only a matter of comfort and expense, but to resort to air conditioning or even most fans means letting the contraption continually impinge on your consciousness. Unless the heat is truly remarkable, it seems far preferable to adapt to it biochemically (such as by eating less - never a better time for a diet!), get used to it over time, or take more showers and so forth. Air conditioning just seems like an addictive noisy expensive nuisance almost every day of the year. Wnt (talk) 14:02, 2 February 2016 (UTC)
- Noise is relative to the kinds of unit you have. My house has three airconditioners (big house!) and you can't hear them running unless you happen to be right under one of the air-return ducts (which are generally not situated in main living areas). Similarly, the 8 ceiling fans we have (one in almost every room) are completely silent - unless the motor bearings are shot or they are seriously out of balance. So the argument of noise is far from universal - and doesn't impinge on the question of whether A/C can be considered a luxury. I'd agree that having quiet A/C is more of a luxury than having to suffer noisy units - but that's not a comparison we're being asked to make.
- I don't know what temperature you regard as "truly remarkable" - but I can assure you that when the humidity is high and the ambient temperature is well over body heat, "taking a shower" will only help if your source of water is cooler than the air - and even then, only briefly. I don't see how eating less helps - certainly when your body doesn't have to work so hard to keep itself warm you don't need so many calories, so everyone tends to eat less when it's hot - but cutting back on food doesn't make you noticeably cooler. I've been living in Texas for over 20 years now - and I can tell you that you never truly get used to temperatures up above body heat - especially when the humidity is high and when there is little or no relief from the heat at night.
- So no, A/C is not an addiction - in the right set of conditions it's as close to being a necessity as I can imagine.
- SteveBaker (talk) 14:23, 2 February 2016 (UTC)
- Basal metabolic rate and thermogenesis are real; the effect is a combination of specific dynamic action during digestion and insulin hormonal activity on the brain.[11] By "addictive" I mean both that it reduces acclimatization and that it encourages bad architectural design -- people run an air conditioner while they have their roof painted black, no reflective insulation or other cooling measures in the attic, and fail to make good use of below-ground spaces, opposing windows, etc. Admittedly, all of this together may be no match for some parts of Texas... might as soon expect the Devil to do without A/C. Wnt (talk) 16:08, 2 February 2016 (UTC)
- Well, that's all that's needed to answer the question we've been posed. You clearly agree that having A/C is not a luxury in some parts of Texas - so clearly there are parts of the world where it isn't a luxury and some places where it is. Our OP is not being very specific as to location - so the general answer is:
- "It's not always a luxury because it's close to being a basic necessity in some parts of the world (such as Texas). In other places it is a luxury because it can easily be replaced with modified behavior. In yet other places (such as Antarctica), it is entirely unnecessary."
- Well, that's all that's needed to answer the question we've been posed. You clearly agree that having A/C is not a luxury in some parts of Texas - so clearly there are parts of the world where it isn't a luxury and some places where it is. Our OP is not being very specific as to location - so the general answer is:
- Basal metabolic rate and thermogenesis are real; the effect is a combination of specific dynamic action during digestion and insulin hormonal activity on the brain.[11] By "addictive" I mean both that it reduces acclimatization and that it encourages bad architectural design -- people run an air conditioner while they have their roof painted black, no reflective insulation or other cooling measures in the attic, and fail to make good use of below-ground spaces, opposing windows, etc. Admittedly, all of this together may be no match for some parts of Texas... might as soon expect the Devil to do without A/C. Wnt (talk) 16:08, 2 February 2016 (UTC)
White tube like things in poor quality diced beef.
[edit]Hello. tonight, I was eating some Iceland (supermarket) diced steak beef chunks for a stir fry, knowing that the quality was poor and full of gristle. I discovered upon biting a piece of the diced steak, that there was a small, white rubbery tube thing in the steak. I know this is hard to describe, but what could this be? It resembled some macaroni, but was it really a ligament or muscle fiber or something? --Commonîo (talk) 21:24, 1 February 2016 (UTC)
- Probably a vein or an artery. --Jayron32 21:26, 1 February 2016 (UTC)
- Or a nerve, of course. Or a miscellaneous bit of fascia. Still edible, of course, if unappetizing. Tevildo (talk) 22:12, 1 February 2016 (UTC)
- Nerves are like tubes? Anna Frodesiak (talk) 00:04, 2 February 2016 (UTC)
- Ganglia (large nerve bundles) can resemble them, sometimes after processing. And perhaps it's best not to eat the white stuff in Iceland beef (I used to live in the UK for a few months, long enough to have shopped at Iceland myself, so I know what Commonîo means) - just on the off chance the cow it came from had BSE. The prions tend to be more present in nerve tissue. loupgarous (talk) 00:11, 2 February 2016 (UTC)
- Nerves are like tubes? Anna Frodesiak (talk) 00:04, 2 February 2016 (UTC)
- Or a nerve, of course. Or a miscellaneous bit of fascia. Still edible, of course, if unappetizing. Tevildo (talk) 22:12, 1 February 2016 (UTC)